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WO2016060025A1 - Engin de chantier - Google Patents

Engin de chantier Download PDF

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Publication number
WO2016060025A1
WO2016060025A1 PCT/JP2015/078378 JP2015078378W WO2016060025A1 WO 2016060025 A1 WO2016060025 A1 WO 2016060025A1 JP 2015078378 W JP2015078378 W JP 2015078378W WO 2016060025 A1 WO2016060025 A1 WO 2016060025A1
Authority
WO
WIPO (PCT)
Prior art keywords
shaft
case
transmission
differential
gear
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/JP2015/078378
Other languages
English (en)
Japanese (ja)
Inventor
吉井　源
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Yanmar Co Ltd
Original Assignee
Yanmar Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Yanmar Co Ltd filed Critical Yanmar Co Ltd
Publication of WO2016060025A1 publication Critical patent/WO2016060025A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
    • B60K17/00—Arrangement or mounting of transmissions in vehicles
    • B60K17/30—Arrangement or mounting of transmissions in vehicles the ultimate propulsive elements, e.g. ground wheels, being steerable
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
    • B60K23/00—Arrangement or mounting of control devices for vehicle transmissions, or parts thereof, not otherwise provided for
    • B60K23/04—Arrangement or mounting of control devices for vehicle transmissions, or parts thereof, not otherwise provided for for differential gearing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60B—VEHICLE WHEELS; CASTORS; AXLES FOR WHEELS OR CASTORS; INCREASING WHEEL ADHESION
    • B60B35/00—Axle units; Parts thereof ; Arrangements for lubrication of axles
    • B60B35/12—Torque-transmitting axles
    • B60B35/14—Torque-transmitting axles composite or split, e.g. half- axles; Couplings between axle parts or sections

Definitions

  • work vehicles such as farm work machines such as tractors and special work machines such as crane trucks.
  • the rear axle cases provided on the left and right sides of the transmission case are divided into a fixed case connected to the transmission case, and a sliding case inserted into the fixed case so as to be slidable left and right.
  • the tread adjustment hydraulic cylinder that is configured to slide the left and right sliding side cases to the left and right is provided integrally on the upper surface side of the left and right fixed side cases, and the left and right sliding side cases are moved by the expansion and contraction of the left and right tread adjustment hydraulic cylinders.
  • the tread between the provided left and right rear running units is configured to be changeable (see, for example, Patent Document 1).
  • the work vehicle has an engine mounted on the front part of the body frame, a transmission case is connected to the rear part of the body frame, and the traveling body is supported by the front and rear traveling parts.
  • the transmission case incorporates, for example, a traveling transmission gear mechanism, a differential gear mechanism, a PTO transmission gear mechanism, and the like.
  • the power of the front engine is transmitted to the rear transmission case, and is transmitted from the differential gear mechanism in the transmission case to at least the left and right rear traveling units. Power is also transmitted from the PTO transmission gear mechanism in the transmission case to a working unit such as a rotary tiller (see, for example, Patent Document 2).
  • the work vehicle also includes a differential lock mechanism that locks the differential of the differential gear mechanism and applies the same rotational speed to the left and right rear traveling units.
  • a differential lock fork that controls a differential lock body that can lock the differential of the differential gear mechanism is attached to a horizontally long differential lock shaft disposed above the differential gear mechanism, and the differential lock along the differential lock shaft By the sliding movement of the fork, the differential gear mechanism is locked or unlocked by the differential lock body (see, for example, Patent Document 3).
  • a spring member that biases the differential lock fork in the locking direction is fitted on the differential lock shaft. The elastic biasing force of the spring member is applied as an auxiliary force to the moving force of the differential lock fork, and smoothly moves the differential lock body to the locked position via the differential lock fork.
  • a portal frame is provided on the upper surface of the housing that connects the engine and the transmission case, a steering shaft is erected on the upper surface of the portal frame, and the rotational movement of the steering shaft is controlled in the left and right directions.
  • a structure in which a power steering hydraulic mechanism for converting to a turning motion of a front wheel is attached in the frame of the portal frame is well known (see, for example, Patent Document 4).
  • the tread adjusting hydraulic cylinder is integrally provided on the upper surface side of the left and right fixed cases, the structure of the rear axle case is different between the specifications with the tread change and the specifications without the tread change. It was different. In other words, for example, even though they are the same model, there is a problem that a dedicated rear axle case must be manufactured for each specification with or without a tread change, and various costs such as manufacturing costs, management costs, and transportation costs increase. It was.
  • This invention makes it a technical subject to provide the work vehicle which improved after examining the above present conditions.
  • the tread adjusting hydraulic cylinder and the piston portion of the lock cylinder are connected to a connecting frame fixed to the sliding side case, and the tread adjusting hydraulic cylinder and the lock cylinder are connected. It is good also as what is comprised symmetrically.
  • the present invention relates to a work vehicle in which a differential mechanism that transmits transmission power to left and right rear traveling parts of a traveling machine body is disposed in a transmission case that shifts the power of an engine.
  • a differential lock fork that controls a differential lock body that can lock the differential of the differential mechanism is attached to the differential lock shaft, and a rotational force is applied to the differential lock shaft and the differential lock fork.
  • a pair of cam members to be converted into the axial direction of the differential lock shaft are provided side by side, the differential lock body is moved to the lock position via the differential lock fork by one cam member, and the lock position is defined by the other cam member It is what you are doing.
  • a biasing member for biasing the differential lock fork in the unlocking direction is attached to the differential lock shaft, and the differential lock body is moved to the unlock position via the differential lock fork by the other cam member.
  • the unlocking position may be defined by the one cam member.
  • each of the cam members includes a V-shaped cam portion formed in a V-shaped notch at the left and right end portions of the base end boss body of the differential lock fork, and the differential lock so as to be in sliding contact with the V-shaped cam portion.
  • a cam follower pin protruding from the shaft may be provided.
  • an opening that penetrates vertically is formed on a lower side of the board support plate, and the power steering hydraulic mechanism is connected to a lower surface side of a closing plate that detachably closes the opening from above.
  • An operation shaft that protrudes upward from the steering hydraulic mechanism may pass through the blocking plate and connect the proximal end side of the steering shaft and the operation shaft via a universal joint.
  • the tread adjusting hydraulic cylinder and the piston portion of the lock cylinder are connected to the connecting frame fixed to the sliding side case, and the tread adjusting hydraulic cylinder and the lock cylinder are connected.
  • the tread adjusting hydraulic cylinder mounted on each of the rear axle cases can be configured in common, and the lock cylinder mounted on each of the rear axle cases can be configured in common. become. For this reason, it is possible to further reduce various costs such as manufacturing costs, management costs, and transportation costs.
  • a horizontally long differential lock shaft is rotatably supported in the transmission case, and a differential lock fork for controlling a differential lock body capable of locking the differential of the differential mechanism is attached to the differential lock shaft, and the differential lock shaft and
  • the differential lock fork is provided with a pair of cam members that convert rotational force into slide force in the axial direction of the differential lock shaft, and the differential lock body is moved to the lock position via the differential lock fork by one cam member.
  • the differential lock mechanism for locking the differential of the differential mechanism can be made compact, and the presence of the other cam member can cause an excess of the differential lock body. The biting can be avoided to prevent the load torque from being closed. For this reason, the unlocking of the differential lock body can always be performed smoothly.
  • an opening that penetrates vertically is formed on the lower side of the board support plate, and the power steering hydraulic mechanism is connected to the lower surface of a closing plate that detachably closes the opening from above, and the power
  • An operating shaft protruding upward from the steering hydraulic mechanism passes through the closing plate and connects the proximal end side of the steering shaft and the operating shaft via a universal joint, so that the power steering hydraulic pressure from the cabin side.
  • a mechanism can be attached, and the assembly workability of the power steering hydraulic mechanism can be improved.
  • FIGS. 1 to 8 the traveling machine body 2 of the tractor 1 is supported by a pair of left and right rear wheels 4 as well as a pair of left and right front wheels 3 as a traveling portion.
  • the pair of left and right rear wheels 4 corresponds to the rear traveling unit.
  • a diesel engine 5 (hereinafter simply referred to as an engine) is mounted on the front portion of the traveling machine body 2, and the tractor 1 is configured to travel forward and backward by driving the rear wheel 4 or the front wheel 3 with the engine 5.
  • the engine 5 is covered with a bonnet 6.
  • a cabin 7 is installed on the upper surface of the traveling machine body 2.
  • Steps 10 on which the operator gets on and off are provided on the left and right outer sides of the cabin 7.
  • a fuel tank 11 for supplying fuel to the engine 5 is provided below the bottom of the cabin 7.
  • the traveling machine body 2 includes an engine frame 14 having a front bumper 12 and a front axle case 13, and left and right machine body frames 15 detachably fixed to a rear portion of the engine frame 14.
  • a front axle 16 is rotatably protruded outward from the left and right ends of the front axle case 13.
  • the front wheels 3 are attached to the left and right ends of the front axle case 13 via the front axle 16.
  • a transmission case 17 is connected to the rear part of the body frame 15 for appropriately changing the rotational power from the engine 5 and transmitting it to the front and rear four wheels 3, 3, 4, 4.
  • a tank frame 18 having a rectangular frame plate shape in a bottom view projecting outward in the left and right directions is bolted to the lower surface sides of the left and right body frames 15 and the mission case 17.
  • the fuel tank 11 of the embodiment is divided into left and right two parts.
  • the left and right fuel tanks 11 are distributed and mounted on the upper surface side of the left and right projecting portions of the tank frame 18.
  • Left and right rear axle cases 19 are mounted on the left and right outer surfaces of the mission case 17 so as to protrude outward.
  • Left and right rear axle cases 20 are rotatably inserted in the left and right rear axle cases 19.
  • the rear wheel 4 is attached to the mission case 17 via the rear axle 20.
  • Upper portions of the left and right rear wheels 4 are covered with left and right rear fenders 21.
  • a hydraulic lifting mechanism 22 that lifts and lowers a ground working machine (not shown) such as a rotary tiller is detachably attached.
  • the ground work machine is connected to the rear portion of the transmission case 17 via a three-point link mechanism 111 including a pair of left and right lower links 23 and a top link 24.
  • a PTO shaft 25 for transmitting a PTO driving force to a working machine such as a rotary tiller is provided to project rearward.
  • a flywheel 26 (see FIGS. 4 to 6, 10, and 11) is directly attached to an output shaft (piston rod) of the engine 5 that protrudes rearward from the rear side of the engine 5.
  • a main shaft 27 projecting rearward from the flywheel 26 and a main transmission input shaft 28 projecting forward from the front side of the transmission case 17 are connected via a power transmission shaft 29 having universal shaft joints at both ends. (See FIGS. 4 to 6).
  • a hydraulic continuously variable transmission 500, a forward / reverse switching mechanism 501, a traveling transmission gear mechanism, a rear wheel differential gear mechanism 506, and the like are arranged.
  • the rotational power of the engine 5 is transmitted to the main transmission input shaft 28 of the transmission case 17 via the main driving shaft 27 and the power transmission shaft 29, and is appropriately shifted by the hydraulic continuously variable transmission 500 and the traveling transmission gear mechanism.
  • the power is transmitted to the left and right rear wheels 4 via the rear wheel differential gear mechanism 506.
  • the front wheel output shaft 30 projecting forward from the front lower part of the transmission case 17 is transmitted to the front wheel projecting rearward from the front axle case 13 containing the front wheel differential gear mechanism 507 via the front wheel drive shaft 31.
  • the shaft 508 is connected. Transmission power by the hydraulic continuously variable transmission 500 and the traveling transmission gear mechanism in the transmission case 17 is transmitted from the front wheel output shaft 30, the front wheel drive shaft 31, and the front wheel transmission shaft 508 to the front wheel differential gear in the front axle case 13. It is configured to be transmitted to the left and right front wheels 3 via a mechanism 507.
  • a steering column 32 is disposed in front of the control seat 8 in the cabin 7.
  • the steering column 32 is erected in a state of being embedded in the back side of the dashboard 33 disposed on the front side inside the cabin 7.
  • a steering handle 9 having a substantially round shape in plan view is attached to the upper end side of the handle shaft that protrudes upward from the upper surface of the steering column 32.
  • a pair of left and right brake pedals 35 for braking the traveling machine body 2 are arranged on the right side of the steering column 32.
  • a forward / reverse switching lever 36 (reverser lever) for switching the traveling direction of the traveling machine body 2 between forward and reverse and a power transmission clutch (not shown) are disconnected.
  • a clutch pedal 37 is provided on the left side of the steering column 32.
  • An erroneous operation preventing body 38 (reverser guard) extending along the forward / reverse switching lever 36 is disposed on the left side of the steering column 32 and below the forward / reverse switching lever 36.
  • an erroneous operation prevention body 38 as a contact preventer below the forward / reverse switching lever 36, the operator is prevented from inadvertently contacting the forward / reverse switching lever 36 when getting on and off the tractor 1.
  • An operation display panel 39 incorporating a liquid crystal panel is provided on the upper rear side of the dashboard 33.
  • Accelerator pedal 41 for controlling the rotational speed of the engine 5 or the vehicle speed is disposed on the right side of the steering column 32 on the floor plate 40 in front of the control seat 8 in the cabin 7. Note that substantially the entire top surface of the floor plate 40 is formed as a flat surface. Side columns 42 are arranged on both the left and right sides of the control seat 8. Between the control seat 8 and the left side column 42, the parking brake lever 43 for executing the operation of maintaining the left and right rear wheels 4 in a braking state and the traveling speed (vehicle speed) of the tractor 1 are forcibly greatly increased.
  • An ultra-low speed lever 44 (creep lever) for reducing the speed
  • a sub-shift lever 45 for switching the output range of the traveling sub-speed gear mechanism in the transmission case 17, and a PTO speed change for switching the driving speed of the PTO shaft 25.
  • a lever 46 is arranged.
  • a differential lock pedal 47 for turning on / off the differential drive of the left and right rear wheels 4 is disposed below the control seat 8.
  • a sub-PTO lever 48 for performing an operation for driving the PTO shaft 25 in synchronization with the vehicle speed or an operation for driving it in the reverse direction is disposed on the left rear side of the control seat 8.
  • an armrest 49 for placing the arm and elbow of the operator seated on the control seat 8 is provided.
  • the armrest 49 is configured separately from the control seat 8 and has a main transmission lever 50 that increases and decreases the traveling speed of the tractor 1 and a dial type that manually changes and adjusts the height position of a ground working machine such as a rotary tiller.
  • Working part position dial 51 (elevating dial).
  • the armrest 49 is configured to be able to be turned up and rotated in a plurality of stages with the rear end lower part as a fulcrum.
  • the left side column 42 includes, in order from the front side, a throttle lever 52 that sets and maintains the rotational speed of the engine 5, and a PTO clutch switch 53 that performs intermittent operation of power transmission from the PTO shaft 25 to a working machine such as a rotary tiller.
  • a plurality of hydraulic operation levers 54 (SCV levers) for switching the hydraulic external take-off valve 430 (see FIG. 14) arranged on the upper surface side of the mission case 17 are arranged.
  • the hydraulic external take-off valve 430 is for controlling supply of hydraulic oil to hydraulic equipment of another work machine such as a front loader retrofitted to the tractor 1.
  • four hydraulic operation levers 54 are arranged in accordance with the number of hydraulic external take-out valves (four stations).
  • left and right front support bases 96 that support the front side of the cabin 7 and left and right rear support bases 97 that support the rear part of the cabin 7 are provided.
  • the front support 96 is bolted to the front and rear intermediate portions of the outer side surfaces of the left and right aircraft frames 15, and the front bottom of the cabin 7 is anti-vibrated on the upper surface of the front support 96 via the anti-vibration rubber body 98.
  • the rear support base 97 is bolted to the middle portion of the left and right widths of the upper surfaces of the left and right rear axle cases 19 that are horizontally extended in the left-right direction, and the vibration-proof rubber body 99 is attached to the upper surface side of the rear support base 97.
  • the rear bottom portion of the cabin 7 is supported by vibration isolation. Further, as shown in FIGS. 4 and 5, etc., the rear support base 97 is disposed on the upper surface side of the rear axle case 19, and the steady bracket 101 is disposed on the lower surface side of the rear axle case 19.
  • the fastening bracket 101 is fastened with bolts, and both ends of the steady rod body 103 with turnbuckles that can be expanded and contracted are connected to the middle portion of the lower link 23 and the steady bracket 101 that extend in the front-rear direction. The horizontal vibration of 23 is prevented.
  • the diesel engine 5 has a cylinder head mounted on a cylinder block having a built-in engine output shaft and piston, and is connected to an air cleaner 221 via a turbocharger 211 on the right side surface of the diesel engine 5 (cylinder head). And an EGR device 210 that recirculates a part of the exhaust gas from the exhaust manifold 204, and a part of the exhaust gas discharged to the exhaust manifold 204 is returned to the intake manifold 203. The maximum combustion temperature during high-load operation is lowered, and NOx (nitrogen oxide) emissions from the diesel engine 5 are reduced.
  • NOx nitrogen oxide
  • the exhaust manifold 204 connected to the tail pipe 229 and the turbocharger 211 are arranged on the left side surface of the diesel engine 5 (cylinder head). That is, the intake manifold 203 and the exhaust manifold 204 are distributed and arranged on the left and right side surfaces along the engine output shaft in the engine 5.
  • a cooling fan 206 is disposed on the front side of the diesel engine 5 (cylinder block).
  • the diesel engine 5 includes a continuously regenerative exhaust gas purification device 224 (DPF) disposed on the upper surface side (above the exhaust manifold 204) of the diesel engine 5, and exhaust gas.
  • a tail pipe 229 is connected to the exhaust side of the purification device 224.
  • the exhaust gas purifying device 224 removes particulate matter (PM) in the exhaust gas discharged from the engine 5 through the tail pipe 229 to the outside of the machine, and at the same time, carbon monoxide (CO) and carbonization in the exhaust gas.
  • Hydrogen (HC) is configured to be reduced.
  • the bonnet 6 has a front grill 231 at the front lower side, and covers the upper surface side and the front surface side of the engine room 200.
  • Side engine covers 232 formed of a perforated plate are arranged on the lower left and right sides of the bonnet 6 to cover the left and right sides of the engine room 200. That is, the hood 6 and the engine cover 232 cover the front, upper, and left and right sides of the diesel engine 5.
  • a radiator 235 having a fan shroud 234 attached to the back side is erected on the engine frame 14 so as to be positioned on the front side of the engine 5.
  • the fan shroud 234 surrounds the outer peripheral side of the cooling fan 206 and allows the radiator 235 and the cooling fan 206 to communicate with each other.
  • An air cleaner 221 is disposed above the front surface of the radiator 235.
  • an oil cooler, a fuel cooler, and the like are installed on the front side of the radiator 235.
  • the pair of left and right body frames 15 are connected by a support beam frame 236.
  • the supporting beam frame 236 is bolted to the left and right airframe frames 15 and is installed on the front end portions (rear side of the engine 5) of the left and right airframe frames 15 via the engine legs having vibration-proof rubber.
  • the rear part of the diesel engine 5 is connected to the upper surface of the support beam frame 236.
  • 1, 2, 4, 5, 11, and 12, left and right front engine legs 238 having anti-vibration rubber are provided in the middle of the pair of left and right engine frames 14.
  • the left and right side surfaces of the front part of the diesel engine 5 are connected. That is, the front side of the diesel engine 5 is supported on the engine frame 14 by vibration isolation, and the rear part of the diesel engine 5 is supported on the front end sides of the pair of left and right body frames 15 via the support beam frame 236.
  • the transmission case 17 includes a front transmission case 112 having a main transmission input shaft 28 and the like, a rear transmission case 113 having a rear axle case 19 and the like, and a front side of the rear transmission case 113 on the rear side of the front transmission case 112.
  • An intermediate case 114 to be connected is provided.
  • the rear ends of the left and right machine body frames 15 are connected to the left and right side surfaces of the intermediate case 114 via the left and right upper and lower machine body connecting shafts 115 and 116.
  • the rear end portions of the left and right airframe frames 15 are connected to the left and right side surfaces of the intermediate case 114 by the two upper airframe connecting shaft bodies 115 and the two lower airframe connecting shaft bodies 116.
  • the transmission case 17 is integrally connected to form the rear part of the traveling machine body 2, and the front transmission case 112 or the power transmission shaft 29 is disposed between the left and right machine body frames 15, so that the front transmission case is provided. 112 and the like are protected.
  • the left and right rear axle cases 19 are attached to the left and right sides of the rear transmission case 113 so as to protrude outward.
  • the intermediate case 114 and the rear transmission case 113 are made of cast iron, while the front transmission case 112 is made of aluminum die cast.
  • the transmission case 17 is divided into the three parts of the front transmission case 112, the intermediate case 114, and the rear case 113, parts such as shafts and gears are attached to the cases 112 to 114, respectively.
  • the front transmission case 112, the intermediate case 114, and the rear transmission case 113 can be assembled. Therefore, the assembly of the mission case 17 can be performed accurately and efficiently.
  • left and right rear axle cases 19 are attached to the left and right sides of the rear transmission case 113, and an intermediate case 114 that connects the front transmission case 112 and the rear transmission case 113 is connected to the left and right body frames 15 constituting the traveling vehicle body 2. Therefore, for example, it is possible to remove the front transmission case 112 while the intermediate case 114 and the rear transmission case 113 are attached to the machine body frame 15 and perform operations such as shaft and gear exchange. Therefore, the frequency of dropping (removing) the entire mission case 17 from the tractor 1 can be remarkably lowered, and the workability during maintenance and repair can be improved.
  • the intermediate case 114 and the rear transmission case 113 are made of cast iron, and the front transmission case 112 is made of aluminum die cast, the intermediate case 114 connected to the body frame 15 and the left and right rear axle cases 19 are made.
  • the rear transmission case 113 to which the two are connected can be configured with high rigidity as a strength member constituting the traveling machine body 2.
  • the front transmission case 112 that is not a strength member can be reduced in weight. Therefore, it is possible to reduce the weight of the transmission case 17 as a whole while sufficiently securing the rigidity of the traveling machine body 2.
  • the hydraulic lifting mechanism 22 includes left and right hydraulic lift cylinders 117 that are controlled by operation of the working unit position dial 51 and the like, and the upper surface of the rear transmission case 113 of the transmission case 17.
  • the left and right lift arms 120 are connected to the left and right lower links 23, and the left and right lift arms 120 are pivotally supported via a lift fulcrum shaft 119 on an openable and closable upper surface lid 118.
  • Left and right lift rods 121 are provided.
  • a part of the right lift rod 121 is formed by a horizontal cylinder 122 for hydraulic control, and the length of the right lift rod 121 is configured to be adjustable by the horizontal cylinder 122.
  • the top link hinge 123 is fixed to the back side of the top cover 118, and the top link 24 is connected to the top link hinge 123 via a hinge pin.
  • the piston of the horizontal cylinder 122 is expanded and contracted to change the length of the right lift rod 121.
  • the angle is configured to change.
  • the transmission case 17 includes a front transmission case 112 having a main transmission input shaft 28 and the like, a rear transmission case 113 having a rear axle case 19 and the like, and a front side of the rear transmission case 113 connected to the rear side of the front transmission case 112.
  • An intermediate case 114 is provided.
  • the mission case 17 is formed in a hollow box shape as a whole.
  • a front lid member 491 is disposed on the front surface of the mission case 17, that is, on the front surface of the front transmission case 112.
  • the front lid member 491 is detachably fastened to the front surface of the front transmission case 112 with a plurality of bolts.
  • a rear cover member 492 is disposed on the rear surface of the transmission case 17, that is, on the rear surface of the rear transmission case 113.
  • the rear lid member 492 is detachably fastened to the rear surface of the rear transmission case 113 with a plurality of bolts.
  • An intermediate partition wall 493 that partitions the front transmission case 112 and the intermediate case 114 is integrally formed on the front side in the intermediate case 114.
  • a rear partition wall 494 that partitions the inside of the rear transmission case 113 forward and backward is integrally formed in the middle part of the rear transmission case 113.
  • the inside of the mission case 17 is divided into three chambers, a front chamber 495, a rear chamber 496, and an intermediate chamber 497, by the middle and rear partition walls 493 and 494.
  • a space between the front lid member 491 and the intermediate partition wall 493 in the transmission case 17 (inside the front transmission case 112) is a front chamber 495.
  • a rear chamber 496 is formed between the rear lid member 492 and the rear partition wall 494 (inside the rear side of the rear transmission case 113).
  • a space between the intermediate partition wall 493 and the rear partition wall 494 is an intermediate chamber 497.
  • the front chamber 495, the intermediate chamber 497, and the rear chamber 496 communicate with each other by cutting out part of the partition walls 493 and 494 so that the hydraulic oil (lubricating oil) in the chambers 495 to 497 can move to each other. is doing.
  • a mechanical creep transmission gear mechanism 502 that shifts rotational power via the hydraulic continuously variable transmission 500 and a forward / reverse switching mechanism 501 described later.
  • a traveling auxiliary transmission gear mechanism 503 and a two-wheel drive / four-wheel drive switching mechanism 504 for switching between the two-wheel drive and the four-wheel drive of the front and rear wheels 3 and 4 are arranged.
  • a forward / reverse switching mechanism 501 is provided in the intermediate chamber 497 of the mission case 17 (inside the intermediate case 114 and the front of the rear transmission case 113) to switch the rotational power from the hydraulic continuously variable transmission 500 in the forward or reverse direction. ing.
  • a PTO transmission mechanism 505 for appropriately changing the rotational power from the engine 5 and transmitting it to the PTO shaft 25, and a creep transmission gear mechanism 502 or A rear wheel differential gear mechanism 506 that transmits rotational power via the traveling auxiliary transmission gear mechanism 503 to the left and right rear wheels 4 is disposed.
  • the creep transmission gear mechanism 502 and the traveling auxiliary transmission gear mechanism 503 correspond to a traveling transmission gear mechanism that multi-shifts the transmission output via the forward / reverse switching mechanism 501.
  • a work case hydraulic pump 481 that is driven by the rotational power of the engine 5 and a pump case 480 that houses the traveling hydraulic pump 482 are attached to the front portion of the rear outer case 113.
  • a flywheel 26 is directly connected to the output shaft of the engine 5 that protrudes rearward from the rear side surface of the engine 5.
  • a main transmission input shaft 28 projecting forward from the front side (front cover member 491) of the transmission case 17 is connected to a main driving shaft 27 projecting rearward from the flywheel 26 via a power transmission shaft 29 having universal joints at both ends. It is connected.
  • the rotational power of the engine 5 is transmitted to the main transmission input shaft 28 of the transmission case 17 (front transmission case 112) via the main driving shaft 27 and the power transmission shaft 29, and the hydraulic continuously variable transmission 500 and the creep transmission gear mechanism.
  • the main transmission input shaft 28 protruding forward from the front lid member 491 extends in the front-rear direction from the front transmission case 112 to the intermediate case 114 (from the front chamber 495 to the intermediate chamber 497).
  • a midway portion before and after the main transmission input shaft 28 is rotatably supported by the intermediate partition wall 493.
  • the rear end side of the main transmission input shaft 28 is rotatably supported by an intermediate auxiliary plate 498 that is detachably fastened to the front surface side (intermediate chamber 497 side) of the rear partition wall 494.
  • the intermediate auxiliary plate 498 and the rear partition wall 494 are arranged so that a gap in the front-rear direction is left between the two plates 498 and 494.
  • an input transmission shaft 511 for transmitting power from the main transmission input shaft 28 is arranged in parallel with the main transmission input shaft 28.
  • a hydraulic continuously variable transmission 500 is disposed via an input transmission shaft 511.
  • the front side of the hydraulic continuously variable transmission 500 is attached to the inner surface side of the front lid member 491 that detachably closes the front opening of the front transmission case 112.
  • the rear end side of the input transmission shaft 511 is rotatably supported by the intermediate auxiliary plate 498 and the rear partition wall 494.
  • the hydraulic continuously variable transmission 500 in the front chamber 495 is an inline type in which a main transmission output shaft 512 is concentrically arranged on an input transmission shaft 511.
  • a cylindrical main transmission output shaft 512 is fitted in a portion of the input transmission shaft 511 in the intermediate chamber 497.
  • the front end side of the main transmission output shaft 512 passes through the intermediate partition wall 493 and is rotatably supported on the intermediate partition wall 493.
  • the rear end side of the main transmission output shaft 512 is rotatably supported by the intermediate auxiliary plate 498. Therefore, the rear end side that is the input side of the input transmission shaft 511 protrudes rearward from the rear end of the main transmission output shaft 512.
  • a main transmission input gear 513 is fitted on the rear end side of the main transmission input shaft 28 (between the intermediate auxiliary plate 498 and the rear partition wall 494) so as not to be relatively rotatable.
  • An input transmission gear 514 that always meshes with the main transmission input gear 513 is fixed to the rear end side of the input transmission shaft 511 (between the intermediate auxiliary plate 498 and the rear partition wall 494). Accordingly, the rotational power of the main transmission input shaft 28 is transmitted to the hydraulic continuously variable transmission 500 via the main transmission input gear 513, the input transmission gear 514, and the input transmission shaft 511.
  • a main transmission high-speed gear 516, a main transmission reverse gear 517, and a main transmission low-speed gear 515 are fitted on the main transmission output shaft 512 so as not to rotate relative to each other for traveling output.
  • the hydraulic continuously variable transmission 500 includes a variable displacement hydraulic pump unit 521 and a constant displacement hydraulic motor unit 522 that is operated by high-pressure hydraulic oil discharged from the hydraulic pump unit 521.
  • the hydraulic pump unit 521 is provided with a pump swash plate 523 that can change the inclination angle with respect to the axis of the input transmission shaft 511 and adjust the amount of hydraulic oil supplied.
  • a main transmission hydraulic cylinder 524 that changes and adjusts the inclination angle of the pump swash plate 523 with respect to the axis of the input transmission shaft 511 is linked to the pump swash plate 523.
  • the main transmission hydraulic cylinder 524 is assembled to the hydraulic continuously variable transmission 500 and unitized as one member.
  • the pump swash plate 523 of the embodiment adjusts the angle in a range between one (positive) maximum inclination angle and the other (negative) maximum inclination angle with a neutral angle of substantially zero inclination (before and after including zero) interposed therebetween. It is possible to set an angle that is inclined to one of the two times when the vehicle speed of the traveling machine body 2 is the lowest (in this case, an inclination angle that is negative and near the maximum).
  • the hydraulic motor unit 522 When the inclination angle of the pump swash plate 523 is substantially zero (neutral angle), the hydraulic motor unit 522 is not driven by the hydraulic pump unit 521, and the main transmission output shaft 512 rotates at substantially the same rotational speed as the input transmission shaft 511. To do.
  • the hydraulic pump unit 521 activates the hydraulic motor unit 522 at a higher speed than the input transmission shaft 511.
  • the main transmission output shaft 512 rotates at a high rotational speed. For this reason, the rotational speed of the hydraulic motor unit 522 is added to the rotational speed of the input transmission shaft 511 and transmitted to the main transmission output shaft 512.
  • the shift power (vehicle speed) from the main shift output shaft 512 is changed in proportion to the tilt angle (positive tilt angle) of the pump swash plate 523 within a range of rotation speed higher than the rotation speed of the input transmission shaft 511. Is done.
  • the pump swash plate 523 is positive and has an inclination angle near the maximum, the traveling machine body 2 reaches the maximum vehicle speed.
  • the hydraulic pump unit 521 decelerates (reverses) the hydraulic motor unit 522, and the input transmission shaft
  • the main transmission output shaft 512 rotates at a rotational speed lower than 511.
  • the rotational speed of the hydraulic motor unit 522 is subtracted from the rotational speed of the input transmission shaft 511 and transmitted to the main transmission output shaft 512.
  • the speed change power from the main speed change output shaft 512 is changed in proportion to the inclination angle (negative inclination angle) of the pump swash plate 523 within the range of the rotation speed lower than the rotation speed of the input transmission shaft 511.
  • the traveling machine body 2 has the minimum vehicle speed.
  • a pump drive gear 484 is fitted on the pump drive shaft 483 that drives both the working machine and traveling hydraulic pumps 481 and 482 so as not to be relatively rotatable.
  • the pump drive gear 484 connects the main transmission input gear 513 of the main transmission input shaft 28 via a flat gear mechanism 485 so that power can be transmitted.
  • a lubricating oil pump 518 is provided between the intermediate auxiliary plate 498 and the rear partition wall 494 to supply hydraulic oil for lubrication to the hydraulic continuously variable transmission 500, the forward / reverse switching mechanism 501 and the like.
  • the pump gear 520 fixed to the pump shaft 519 of the lubricating oil pump 518 is always meshed with the input transmission gear 514 of the input transmission shaft 511. Therefore, the working machine and traveling hydraulic pumps 481 and 482 and the lubricating oil pump 518 are driven by the rotational power of the engine 5.
  • a planetary gear mechanism 526 which is a forward high-speed gear mechanism, and a low-speed gear pair 525, which is a forward low-speed gear mechanism, are disposed at a location in the intermediate chamber 497 of the main transmission input shaft 28 (on the rear side of the main transmission input shaft 28). is doing.
  • the planetary gear mechanism 526 includes a sun gear 531 that rotates integrally with an input-side transmission gear 529 that is rotatably supported on the main transmission input shaft 28, and a carrier 532 that rotatably supports a plurality of planetary gears 533 on the same radius. And a ring gear 534 having inner teeth on the inner peripheral surface.
  • the sun gear 531 and the ring gear 534 are rotatably fitted on the main transmission input shaft 28.
  • the carrier 532 is fitted to the main transmission input shaft 28 so as not to be relatively rotatable.
  • the sun gear 531 meshes with each planetary gear 533 of the carrier 532 from the inside of the radius. Further, the inner teeth of the ring gear 534 mesh with the planetary gears 533 from the radially outer side.
  • An output side transmission gear 530 that rotates integrally with the ring gear 534 is also rotatably supported on the main transmission input shaft 28.
  • the input-side low-speed gear 527 and the output-side low-speed gear 528 constituting the low-speed gear pair 525 have an integral structure, and can rotate between the planetary gear mechanism 526 and the main transmission input gear 513 of the main transmission input shaft 28. It is pivotally supported.
  • the main transmission input shaft 28, the input transmission shaft 511, the travel relay shaft 535 extending in parallel with the main transmission output shaft 512, and A travel transmission shaft 536 is disposed.
  • the front end side of the travel relay shaft 535 is rotatably supported by the intermediate partition wall 493.
  • a rear end side of the travel relay shaft 535 is rotatably supported on the intermediate auxiliary plate 498.
  • the front end side of the traveling transmission shaft 536 is rotatably supported by the intermediate partition wall 493.
  • the rear end side of the travel transmission shaft 536 is rotatably supported by the intermediate auxiliary plate 498.
  • the forward / reverse switching mechanism 501 is provided on the traveling relay shaft 535. That is, the traveling relay shaft 535 has a forward high-speed gear 540 coupled by a wet multi-plate forward high-speed hydraulic clutch 539, a reverse gear 542 coupled by a wet multi-plate reverse hydraulic clutch 541, and a wet multi-plate. A forward low-speed gear 538 connected by a forward low-speed hydraulic clutch 537 of the mold is fitted. A travel relay gear 543 is fitted between the forward high speed hydraulic clutch 539 and the reverse gear 542 in the travel relay shaft 535 so as not to be relatively rotatable. A travel transmission gear 544 that always meshes with the travel relay gear 543 is fitted to the travel transmission shaft 536 so as not to be relatively rotatable.
  • the main transmission low speed gear 515 of the main transmission output shaft 512 is always meshed with the input low speed gear 527 of the low speed gear pair 525 on the main transmission input shaft 28 side, and the output low speed gear 528 is always meshed with the forward low speed gear 538.
  • the main transmission high speed gear 516 of the main transmission output shaft 512 is always meshed with the input transmission gear 529 of the planetary gear mechanism 526 on the main transmission input shaft 28 side, and the output transmission gear 530 is always meshed with the forward high speed gear 540.
  • a main transmission reverse gear 517 of the main transmission output shaft 512 is always meshed with the reverse gear 542.
  • the forward low-speed hydraulic clutch 537 or the forward high-speed hydraulic clutch 539 When the forward / reverse switching lever 36 is operated to the forward side, the forward low-speed hydraulic clutch 537 or the forward high-speed hydraulic clutch 539 is in a power connection state, and the forward low-speed gear 538 or forward high-speed gear 540 and the travel relay shaft 535 are connected to each other so as not to be relatively rotatable. Is done. As a result, forward low-speed or high-speed rotational power is transmitted from the main transmission output shaft 512 to the travel relay shaft 535 via the low-speed gear pair 525 or the planetary gear mechanism 526, and power is transmitted from the travel relay shaft 535 to the travel transmission shaft 536. Communicated.
  • the reverse hydraulic clutch 541 When the forward / reverse switching lever 36 is operated to the reverse side, the reverse hydraulic clutch 541 enters a power connection state, and the reverse gear 542 and the travel relay shaft 535 are coupled so as not to be relatively rotatable. As a result, the reverse rotational power is transmitted from the main transmission output shaft 512 to the travel relay shaft 535 via the low speed gear pair 525 or the planetary gear mechanism 526, and the power is transmitted from the travel relay shaft 535 to the travel transmission shaft 536.
  • a mechanical creep transmission gear mechanism 502 and a traveling auxiliary transmission gear mechanism 503 for shifting rotational power via the forward / reverse switching mechanism 501 are arranged in the front chamber 495 of the transmission case (in the front transmission case 112).
  • a travel counter shaft 545 extending coaxially with the travel transmission shaft 536 is disposed in the front chamber 495 (in the front transmission case 112).
  • a sub-transmission shaft 546 extending in parallel with the travel counter shaft 545 is disposed from the front transmission case 112 to the rear transmission case 113 (from the front chamber 495 through the intermediate chamber 497 to the rear chamber 496).
  • the front end side of the travel counter shaft 545 is rotatably supported by the front lid member 491.
  • the rear end side of the travel counter shaft 545 is rotatably supported by the intermediate partition wall 493.
  • the front end side of the auxiliary transmission shaft 546 is rotatably supported by the front lid member 491.
  • the middle part of the auxiliary transmission shaft 546 is rotatably supported by the intermediate partition wall 493.
  • the rear end side of the auxiliary transmission shaft 546 is rotatably supported by the intermediate auxiliary plate 498 and the rear partition wall 494.
  • a transmission gear 547 and a creep gear 548 are provided on the rear side of the travel counter shaft 545.
  • the transmission gear 547 is rotatably fitted to the travel counter shaft 545 and is pivotally supported on the intermediate partition wall 493 while being connected to the travel transmission shaft 536 so as to rotate integrally therewith.
  • the creep gear 548 is fitted on the travel counter shaft 545 so as not to be relatively rotatable.
  • a creep shifter 549 is spline-fitted between the transmission gear 547 and the creep gear 548 of the travel counter shaft 545 so as not to be relatively rotatable and slidable in the axial direction.
  • the creep shifter 549 slides by turning the ultra low speed lever 44 on and off, and the transmission gear 547 and the creep gear 548 are alternatively connected to the travel counter shaft 545.
  • a reduction gear pair 550 is rotatably fitted in a portion of the auxiliary transmission shaft 546 in the front chamber 495 (front transmission case 112).
  • the input side reduction gear 551 and the output side reduction gear 552 constituting the reduction gear pair 550 have an integral structure, and the transmission gear 547 of the travel counter shaft 545 always meshes with the input side reduction gear 551 of the auxiliary transmission shaft 546,
  • the creep gear 548 is always meshed with the output side reduction gear 552.
  • a low speed relay gear 553 and a high speed relay gear 554 are provided on the front side of the travel counter shaft 545.
  • the low speed relay gear 553 is fixed to the travel counter shaft 545.
  • the high-speed relay gear 554 is fitted on the travel counter shaft 545 so as not to be relatively rotatable.
  • a low-speed gear 555 that meshes with the low-speed relay gear 553 and a high-speed gear 556 that meshes with the high-speed relay gear 554 are rotatably fitted on the auxiliary transmission shaft 546 on the front side of the reduction gear pair 550.
  • a sub-transmission shifter 557 is spline-fitted between the low-speed gear 555 and the high-speed gear 556 in the sub-transmission shaft 546 so as not to be relatively rotatable and slidable in the axial direction.
  • the sub transmission shifter 557 slides and the low speed gear 555 and the high speed gear 556 are alternatively connected to the sub transmission shaft 546.
  • the creep gear 548 is connected to the travel counter shaft 545 so as not to be relatively rotatable, and the low speed gear 555 is connected to the sub transmission shaft 546.
  • a relatively low speed travel driving force is output from the travel transmission shaft 536 to the front wheel 3 and the rear wheel 4 via the travel counter shaft 545 and the auxiliary transmission shaft 546.
  • the ultra-low speed lever 44 and the auxiliary transmission lever 45 are interlocked and connected via a shift check member (details will be described later), and the high-speed side operation of the auxiliary transmission lever 45 and the entry operation of the ultra-low speed lever 45 are performed. It is configured to prohibit compatibility. That is, the sub-shift lever 45 cannot be operated to the high speed side when the ultra-low speed lever 44 is operated and the ultra-low speed lever 44 cannot be operated when the sub-speed lever 45 is operated to the high speed side. .
  • the transmission gear 547 is connected to the travel counter shaft 545 so as not to rotate relative to it, and the low speed gear 555 cannot be rotated relative to the sub transmission shaft 546.
  • a low-speed traveling driving force is output from the traveling transmission shaft 536 to the front wheels 3 and the rear wheels 4 via the traveling counter shaft 545 and the auxiliary transmission shaft 546.
  • the transmission gear 547 is connected to the travel counter shaft 545 so as not to rotate relative to it, and the high speed gear 556 cannot be rotated relative to the sub transmission shaft 546.
  • a high-speed travel driving force is output from the travel transmission shaft 536 to the front wheels 3 and the rear wheels 4 via the travel counter shaft 545 and the auxiliary transmission shaft 546.
  • the rear end side of the auxiliary transmission shaft 546 passes through the rear partition wall 494 and extends into the rear chamber 496.
  • a pinion 558 is provided at the rear end of the auxiliary transmission shaft 546.
  • a rear wheel differential gear mechanism 506 for transmitting the driving force to the left and right rear wheels 4 is disposed in the rear chamber 496 (inside the rear side of the rear transmission case 113).
  • the rear wheel differential gear mechanism 506 includes a ring gear 559 that meshes with the pinion 558 of the auxiliary transmission shaft 546, a differential gear case 560 provided in the ring gear 559, and a pair of differential output shafts 561 that extend in the left-right direction. Yes.
  • a differential output shaft 561 is connected to the rear axle 20 via a final gear 562 and the like.
  • the rear wheel 4 is attached to the front end side of the rear axle 20.
  • the left and right differential output shafts 561 are provided with brake mechanisms 563, respectively.
  • the brake mechanism 563 applies brakes to the left and right rear wheels 4 by two systems of operation and automatic control of the brake pedal 35 and the parking brake lever 43. That is, each brake mechanism 563 is configured such that the brake is applied to the corresponding differential output shaft 561 and the rear wheel 4 when the brake pedal 35 is depressed or the parking brake lever 43 is pulled up.
  • the brake cylinder 630 is actuated by the switching operation of the autobrake solenoid valve 631 (see FIG. 14) with respect to the rear wheel 4 on the inside of the turn.
  • the brake mechanism 563 for the rear wheel 4 is configured to automatically perform a braking operation (so-called autobrake). For this reason, the tractor 1 can easily execute a small turning turn such as a U-turn (direction change at a headland in a field).
  • the differential gear mechanism 506 for the rear wheels is provided with a differential lock mechanism 585 that stops its own differential (the left and right differential output shafts 561 are always driven at a constant speed).
  • the differential lock body 753 (details will be described later) of the differential lock mechanism 585 is engaged with the differential gear case 560 by the depression operation of the differential lock pedal 47, the left and right differential output shafts 561 (in the embodiment, the left differential output shaft 561). ) Is fixed, the differential function of the differential gear case 560 is stopped, and the left and right differential output shafts 561 are driven at a constant speed.
  • a two-wheel drive / four-wheel drive switching mechanism 504 is disposed in the front chamber 495 (front transmission case 112) of the mission case.
  • a front wheel input shaft 568 and a front wheel output shaft 30 extending in parallel with the travel counter shaft 545 and the auxiliary transmission shaft 546 are disposed in the front chamber 495 (in the front transmission case 112).
  • a driven gear 569 fitted to the front wheel input shaft 568 so as not to rotate relative to the main drive gear 569 fitted so as not to rotate relative to the front end side of the auxiliary transmission shaft 546 is always meshed.
  • a double-speed relay gear 571 and a four-wheel drive relay gear 572 are fitted to the front wheel input shaft 568 so as not to rotate relative to each other on both sides of the driven gear 570.
  • the front wheel output shaft 30 is provided with a 2WD 4WD switching mechanism 504. That is, the front wheel output shaft 30 is fitted with a double speed gear 574 connected by a wet multi-plate type double-speed hydraulic clutch 573 and a four-wheel drive gear 576 connected by a wet multi-plate type four-wheel hydraulic clutch 575. is doing.
  • the double speed relay gear 571 of the front wheel input shaft 568 is always meshed with the double speed gear 574 of the front wheel output shaft 30, and the four-wheel drive relay gear 572 is meshed with the four-wheel gear 576.
  • the four-wheel drive hydraulic clutch 575 When a drive changeover switch or drive changeover lever (not shown) is operated to the four-wheel drive side, the four-wheel drive hydraulic clutch 575 is in a power connection state, and the front wheel output shaft 30 and the four-wheel drive gear 576 are connected so as not to be relatively rotatable. Then, as a result of the rotational power being transmitted from the auxiliary transmission shaft 546 to the front wheel output shaft 30 via the front wheel input shaft 568 and the four-wheel drive gear 576, the tractor 1 is a four-wheeled vehicle driven by the front wheel 3 together with the rear wheel 4. It becomes a driving state.
  • the double speed hydraulic clutch 573 is in a power connection state, and the front wheel output shaft 30 and the double speed gear 574 are connected so as not to be relatively rotatable. Then, the rotational power is transmitted from the auxiliary transmission shaft 546 to the front wheel output shaft 30 via the front wheel input shaft 568 and the double speed gear 574, so that the rotational speed of the front wheel 3 by the rotational power via the four-wheel drive gear 576 is increased.
  • the front wheel 3 is driven at a high speed about twice as high.
  • the front wheel differential gear mechanism 507 that transmits a driving force to the left and right front wheels 3 is disposed.
  • the front wheel differential gear mechanism 507 includes a ring gear 578 that meshes with a pinion 577 provided on the front end side of the front wheel transmission shaft 508, a differential gear case 579 provided on the ring gear 578, and a pair of differential output shafts 580 extending in the left-right direction. And.
  • a differential output shaft 580 is connected to the front axle 16 via a final gear 581 or the like.
  • the front wheel 3 is attached to the front end side of the front axle 16.
  • a steering hydraulic cylinder 622 (see FIG. 14) for power steering is provided on the outer surface of the front axle case 13 to change the traveling direction of the front wheel 3 to the left and right by the steering operation of the steering handle 9.
  • a PTO transmission mechanism 505 that transmits power from the engine 5 to the PTO shaft 25 is disposed in the rear chamber 496 of the transmission case 17 (inside the rear side of the rear transmission case 113).
  • a PTO input shaft 591 extending coaxially with the main transmission input shaft 28 is connected to the rear end side of the main transmission input shaft 28 via a PTO hydraulic clutch 590 for power transmission interruption.
  • the PTO input shaft 591 is disposed in the rear chamber 496.
  • the front end side of the PTO input shaft 591 is rotatably supported on the rear partition wall 494. As shown in FIG.
  • upper and lower support wall portions 613 and 614 that partition the rear chamber 496 forward and backward are integrally formed in the rear chamber 496.
  • a midway portion between the front and rear of the PTO input shaft 591 is rotatably supported on the upper support wall portion 613 in the rear chamber 496.
  • the rear end side of the PTO input shaft 591 is rotatably supported on the inner surface side of the rear cover member 492.
  • a PTO transmission shaft 592, a PTO counter shaft 593, and a PTO shaft 25 extending in parallel with the PTO input shaft 591 are disposed.
  • the front end side of the PTO transmission shaft 592 is rotatably supported on the upper support wall 613, and the rear end side of the PTO transmission shaft 592 is rotatably supported on the inner surface side of the rear lid member 492.
  • the front end side of the PTO counter shaft 593 is rotatably supported on the lower support wall portion 614, and the rear end side of the PTO counter shaft 593 is rotatably supported on the inner surface side of the rear lid member 492.
  • the PTO shaft 25 protrudes rearward from the rear lid member 492.
  • a front end side of the PTO shaft 25 is rotatably supported on the lower support wall portion 614.
  • the PTO hydraulic clutch 590 When the power connection operation of the PTO clutch switch 53 is performed, the PTO hydraulic clutch 590 is in a power connection state, and the main transmission input shaft 28 and the PTO input shaft 591 are coupled so as not to be relatively rotatable. As a result, rotational power is transmitted from the main transmission input shaft 28 toward the PTO input shaft 591.
  • the PTO input shaft 591 is provided with a medium speed input gear 597, a low speed input gear 595, a high speed input gear 596, and a reverse shifter gear 598 in order from the front side.
  • the medium-speed input gear 597, the low-speed input gear 595, and the high-speed input gear 596 are fitted on the PTO input shaft 591 so as not to be relatively rotatable.
  • the reverse shifter gear 598 is spline-fitted to the PTO input shaft 591 so as not to rotate relative to the PTO input shaft 591 and to be slidable in the axial direction.
  • the PTO transmission shaft 592 is rotatably fitted with a PTO medium speed gear 601 that meshes with the medium speed input gear 597, a PTO low speed gear 599 that meshes with the low speed input gear 595, and a PTO high speed gear 600 that meshes with the high speed input gear 596. is doing.
  • a pair of front and rear PTO transmission shifters 602 and 603 are spline-fitted to the PTO transmission shaft 592 so as not to be relatively rotatable and to be slidable in the axial direction.
  • the first PTO shift shifter 602 is disposed between the PTO medium speed gear 601 and the PTO low speed gear 599.
  • the second PTO speed shifter 603 is disposed on the rear end side with respect to the PTO high speed gear 600.
  • the pair of front and rear PTO shift shifters 602 and 603 are configured to slide in the axial direction in conjunction with the operation of the PTO shift lever 46.
  • a PTO transmission gear 604 is fixed between the PTO low-speed gear 599 and the PTO high-speed gear 600 in the PTO transmission shaft 592.
  • the PTO counter shaft 593 has a PTO counter gear 605 that meshes with the PTO transmission gear 604, a PTO relay gear 606 that meshes with a PTO output gear 608 that is non-rotatably fitted to the PTO shaft 25, and a PTO reverse gear 607. It is impossible to fit.
  • the reverse shifter gear 598 slides and the reverse shifter gear 598 meshes with the PTO reverse gear 607 of the PTO counter shaft 593. ing.
  • the pair of front and rear PTO speed shifters 602 and 603 slide along the PTO speed change shaft 592, and the PTO low speed gear 595, the PTO medium speed gear 597, and the PTO high speed gear 596 become the PTO speed change shaft. 592 is alternatively connected.
  • low-speed to high-speed PTO shift outputs are transmitted from the PTO shift shaft 592 to the PTO counter shaft 593 via the PTO transmission gear 604 and the PTO counter gear 605, and further, the PTO relay gear 607 and the PTO output gear 608 are transmitted. Is transmitted to the PTO shaft 25.
  • the reverse shifter gear 598 meshes with the PTO reverse gear 607, and the rotational power of the PTO input shaft 591 is transmitted to the PTO counter shaft 593 via the reverse shifter gear 598 and the PTO reverse gear 607. Then, the reverse PTO shift output is transmitted from the PTO counter shaft 593 to the PTO shaft 25 via the PTO relay gear 607 and the PTO output gear 608.
  • the PTO speed change mechanism 505 of the embodiment is located behind the upper and lower support wall portions 613 and 614 in the rear chamber 496.
  • a rear wheel differential gear mechanism 506 is disposed in front of the upper and lower support wall portions 613 and 614 in the rear chamber 496.
  • the rear wheel differential gear mechanism 506 and the PTO transmission mechanism 505 are selected and arranged in a simple and compact manner. The assembling workability and maintainability of the case 17 are improved.
  • the PTO speed change mechanism 505 is configured to be able to enter and leave the chamber 496 behind the upper and lower support walls 613 and 614.
  • the PTO transmission mechanism 505 is mounted on the rear side of the rear chamber 496 from the upper and lower support wall portions 613 and 614, the PTO transmission mechanism 505 is supported by the upper and lower support wall portions 613 and 614 and the rear lid member 492. ing.
  • the assembly workability and disassembly workability of the mission case 17 and the maintenance performance of the PTO transmission mechanism 505 can be further improved.
  • the PTO input shaft 591 and the PTO transmission shaft 592 are supported by the upper support wall portion 613 and the rear cover member 492, and the PTO counter shaft 593 and the PTO shaft 25 are supported by the lower support wall portion 614 and the rear cover member 492. Is supported. Then, the positional relationship between these shafts 25, 591 to 593 is set so as to be positioned at the top of a rectangle in a rear view (see FIG. 21), and the upper PTO input shaft 591 to the middle PTO speed change shaft 592 and the PTO counter shaft. The PTO output is transmitted to the lower PTO shaft 25 via 593. With this configuration, the reaction forces of the shafts 25, 591 to 593 accompanying the increase in PTO output can be offset. As a result, vibration transmission to the mission case 17 and the traveling machine body 2 can be reduced.
  • a longitudinal longitudinal vehicle speed tuning shaft 564 extending in parallel with the auxiliary transmission shaft 546 is disposed from the intermediate chamber 497 to the rear chamber 496.
  • a vehicle speed tuning input gear 565 is fitted on the front end side of the vehicle speed tuning shaft 564 so as not to be relatively rotatable.
  • the vehicle speed tuning input gear 565 is always meshed with a power branch gear 566 that is fitted in a position in the intermediate chamber 497 of the auxiliary transmission shaft 546 so as not to be relatively rotatable.
  • a vehicle speed tuning output gear 610 that is rotatably fitted to the front side of the PTO output gear 608 in the PTO shaft 25 is always meshed with a vehicle speed tuning relay gear 609 fixed to the rear end portion of the vehicle speed tuning shaft 564.
  • a vehicle speed tuning shifter 611 is spline-fitted between the vehicle speed tuning output gear 610 and the PTO output gear 608 of the PTO shaft 25 so as not to be relatively rotatable and slidable in the axial direction.
  • the function of the sub PTO lever 48 is made different depending on the drive specification of the PTO shaft 25.
  • the reverse shifter gear 598 is slid by manual operation of the sub PTO lever 48 and the reverse PTO shift output is transmitted to the PTO shaft 25.
  • the vehicle speed synchronization shifter 611 is slid by manual operation of the sub-PTO lever 48, and the PTO shift output synchronized with the vehicle speed is transmitted to the PTO shaft 25.
  • the PTO speed change lever 46 and the sub PTO lever 48 are interlocked and connected via a PTO check member (details will be described later). It is configured to prohibit compatibility with the lever 48 entering operation. In other words, the PTO speed change lever 46 cannot be shifted to any position other than neutral when the sub PTO lever 48 is engaged, and the sub PTO lever 48 cannot be engaged when the speed change operation is performed other than neutral. ing.
  • the hydraulic circuit 620 of the tractor 1 includes a working machine hydraulic pump 481 and a traveling hydraulic pump 482 that are driven by the rotational power of the engine 5.
  • the mission case 17 is used as a working oil tank, and the working oil in the mission case 17 is supplied to the working machine hydraulic pump 481 and the traveling hydraulic pump 482.
  • the traveling hydraulic pump 482 is connected to the steering hydraulic cylinder 622 for power steering by the steering handle 9 through the power steering hydraulic mechanism 621 and is a closed loop that connects the hydraulic pump 521 of the hydraulic continuously variable transmission 500 and the hydraulic motor 522. It is connected to the oil passage 623. While the engine 5 is being driven, the hydraulic oil from the traveling hydraulic pump 482 is always replenished to the closed loop oil passage 623.
  • the traveling hydraulic pump 482 includes a main transmission hydraulic switching valve 624 for the main transmission hydraulic cylinder 524 of the hydraulic continuously variable transmission 500, a double speed hydraulic switching valve 625 for the double speed hydraulic clutch 573, and a four-wheel drive for the four-wheel hydraulic clutch 575.
  • the hydraulic switching valve 626 is connected to a PTO clutch electromagnetic valve 627 for the PTO hydraulic clutch 590 and a switching valve 628 operated thereby.
  • the traveling hydraulic pump 482 includes left and right autobrake solenoid valves 631 as switching valves that actuate a pair of left and right autobrake brake cylinders 630, and a forward low speed clutch solenoid valve 632 that actuates a forward low speed hydraulic clutch 537.
  • the work machine hydraulic pump 481 is configured to provide a tread (distance between wheels) between a plurality of hydraulic external extraction valves 430 arranged on the upper surface of the hydraulic lifting mechanism 22 on the rear side of the upper surface of the mission case 17 and the left and right rear wheels 4.
  • Left and right tread adjustment solenoid valves 646 that control the supply of hydraulic oil to the right and left tread adjustment hydraulic cylinders 645, and a tilt control solenoid valve 647 that controls the supply of hydraulic oil to the horizontal cylinder 122 provided on the right lift rod 121 ,
  • An ascending oil pressure switching valve 648 and a descending oil pressure switching valve 649 for controlling the supply of hydraulic oil to the hydraulic lift cylinder 117 in the hydraulic lifting mechanism 22, an ascending control electromagnetic valve 650 for switching the ascending oil pressure switching valve 648, and a descending oil pressure
  • the switching valve 649 is connected to a lowering control electromagnetic valve 651 for operating.
  • the hydraulic circuit 620 of the tractor 1 includes a lubricating oil pump 518 that is driven by the rotational power of the engine 5 in addition to the working machine hydraulic pump 481 and the traveling hydraulic pump 482 described above.
  • the lubricating oil pump 518 includes a PTO clutch hydraulic pressure switching valve 641 that supplies hydraulic oil (lubricating oil) to the lubricating portion of the PTO hydraulic clutch 590, and a lubricating portion of the input transmission shaft 511 that supports the hydraulic continuously variable transmission 500.
  • a rear lid member 492 that detachably closes the rear opening of the transmission case 17 is provided, and the rear lid member 492 is detachably attached to the rear chamber 496 behind the support wall portions 613 and 614.
  • the PTO transmission mechanism 505 is configured to be able to enter and exit, and the PTO transmission mechanism 505 is mounted on the rear side of the rear chamber 496 with respect to the support wall portions 613 and 614, the support wall portions 613 and 614 Since the PTO transmission mechanism 505 is supported by the rear cover member 492, the PTO transmission mechanism 505 can be exposed by removing the rear cover member 492 from the transmission case 17. Therefore, the assembly workability and disassembly workability of the transmission case 17 and the maintenance performance of the PTO transmission mechanism 505 can be further improved.
  • a pair of brake cylinders 630 and a pair of autobrake solenoid valves 631 are assembled into a brake control case 664 to form a unit.
  • a brake control case 664 incorporating a pair of brake cylinders 630 and a pair of autobrake solenoid valves 631 is detachably fastened to an upper front portion of the rear transmission case 113.
  • a PTO valve case 663 is disposed on the left outer surface of the mission case 17, that is, on the front portion on the left outer surface of the rear transmission case 113.
  • the brake control case 664 is disposed on the front upper surface of the rear transmission case 113. Therefore, the PTO valve case 663 and the brake control case 664 are placed close to each other on the outer surface side of the rear transmission case 113. Since the hydraulic piping to the brake control case 664 and the hydraulic piping to the PTO valve case 663 (PTO clutch electromagnetic valve 627 and switching valve 628) are close to each other, they are shared.
  • An auto brake valve 631 for controlling the brake cylinder 630 and the auto brake valve 631 is assembled to the brake control case 664 to form a unit, and the brake control case 664 is disposed in front of the hydraulic lifting mechanism 22 in the upper surface of the mission case 17.
  • the brake control case 664 incorporating the pair of brake cylinders 630 and the pair of auto brake valves 631 can be disposed, and space saving can be achieved.
  • the hydraulic system related to the braking of the work vehicle can be made compact. In the work vehicle production line, it is possible to reduce the number of steps for assembling the brake related hydraulic system.
  • the pair of brake cylinders 630 and the pair of auto brake valves 631 can be attached and detached together with the brake control case 664 in front of the hydraulic lifting mechanism 22 on the upper surface of the transmission case 17. Maintainability can be improved.
  • a longitudinally long board support plate 308 (see FIG. 26) for fixing and supporting the dashboard 33 is erected on the front side inside the cabin 7, and a horizontally long brake pedal shaft is provided in the middle of the board support plate 308.
  • 720 is supported.
  • the brake pedal shaft 720 is fitted with base end boss portions 35 a of the left and right brake pedals 35.
  • the base end boss portion 35a of the left brake pedal 35 is connected so as to rotate integrally with the brake pedal shaft 720, and the base end boss portion of the right brake pedal 35 is rotatably fitted to the brake pedal shaft 720. is doing.
  • a pair of left and right brake operation shafts 722 are supported on the left and right lower sides of the board support plate 308.
  • Left and right brake operation boss bodies 723 are rotatably fitted to the left and right brake operation shafts 722, respectively.
  • Three arms 724 to 726 protrude from each brake operation boss body 723.
  • the central arm 724 located at the center of the left and right is connected to the corresponding pedal shaft arm 721 via the vertically long link rod 727.
  • the lower end side of the link rod 727 is pivotally attached to the central arm 724, and the upper end side of the link rod 727 is pivotally attached to the pedal shaft arm 721.
  • the outer arm 725 positioned on the left and right outer sides is pivotally attached to the front end side of the longitudinally extending brake rod 728 so as to be rotatable.
  • braking arms 729 for braking the left and right brake mechanisms 563 are provided on the left and right outer surfaces of the rear transmission case 113 so as to be able to rotate back and forth.
  • the rear end side of the brake rod 728 is pivotally attached to the front end side of the brake arm 729 so as to be rotatable.
  • the left and right brake mechanisms 563 are operated substantially simultaneously, and the left and right rear wheels 4 are braked.
  • a combination of the pedal shaft arm 721, the brake operation boss body 723, the link rod 727, the brake rod 728, and the brake arm 729 corresponds to the brake link body 730.
  • an inner arm 726 positioned on the left and right inner side is pivotally attached to a front end side of a push-pull wire 731 as a rope member so as to be rotatable.
  • left and right relay links 732 provided corresponding to the brake cylinders 630 are arranged on the left side (brake cylinder 630 side) of the brake control case 664 in the upper surface front portion of the rear transmission case 113. (See FIG. 23).
  • the rear end side of the push-pull wire 731 is pivotably attached to the left end side (one end side) of the corresponding relay link 732.
  • the right end side (other end side) of each relay link 732 is pivotally attached to the corresponding brake cylinder 630.
  • the brake cylinder 630 protrudes by the switching operation of the autobrake solenoid valve 631 with respect to the rear wheel 4 on the inside of the turn, and the push-pull wire 731 is moved via the corresponding relay link 732. Pull backwards. Then, the brake rod 728 is pushed rearward substantially simultaneously via the brake operation boss body 723, and the brake arm 729 rotates backward. As a result, the brake mechanism 563 for the rear wheel 4 inside the turn is automatically braked, and the rear wheel 4 inside the turn is braked (so-called autobrake).
  • the first brake pedal 35 is not operated to follow between the left and right brake link bodies 730 and the left and right brake pedals 35 when the brake mechanism 563 is operated by the brake cylinder 630 (when the automatic brake is operated).
  • An accommodation member 733 is provided.
  • a second interchangeable member 736 is provided between the left and right brake link bodies 730 and the left and right push-pull wires 731 to prevent the brake cylinder 630 from following up when the brake mechanism 563 is operated by the brake pedal 35.
  • the first accommodation member 733 of the embodiment is formed on the lower end side of the link rod 727 and the central accommodation pin 734 that pivotably attaches to the lower end side of the link rod 727 and the central arm 724 of the brake operation boss body 723.
  • a vertically long first long hole 735 is used.
  • a central accommodation pin 734 is loosely fitted in the first elongated hole 735 of the link rod 727.
  • the second interchangeable member 736 of the embodiment includes an inner interchangeable pin 737 that pivotably attaches the front end side of the push-pull wire 731 and the inner arm 726 of the brake operation boss body 723, and a front end holding portion of the push-pull wire 731. It is comprised with the 2nd long hole 738 of the front-back longitudinal direction formed in this.
  • An inner accommodation pin 737 is loosely fitted in the second elongated hole 738 on the push-pull wire 731 side.
  • Both left and right braking arms 729 are linked to a parking brake lever 43 disposed between the control seat 8 and the left side column 42 via a parking brake wire 739 which is an example of a rope member. .
  • a parking brake wire 739 which is an example of a rope member.
  • the left and right braking arms 729 are rotated rearward via the left and right wires 739, the left and right brake mechanisms 563 are operated substantially simultaneously, and the left and right rear wheels 4 are braked. become.
  • the left and right brake arms 729 are rotated rearward and the left and right brake rods 728 are pulled rearward substantially simultaneously, but the central interchange pin 734 of the central arm 724 only moves upward in the first elongated hole 735.
  • the link rod 727 and therefore the brake pedal 35 are not moved.
  • the inner interchange pin 737 of the inner arm 726 only moves backward in the second elongated hole 738, and does not cause the left and right push-pull wires 731 and therefore both brake cylinders 630 to follow. That is, when the parking brake lever 43 is operated, neither the brake pedal 35 nor the brake cylinder 630 is operated to follow.
  • 17 and a rear traveling unit 4 provided on both left and right sides of the transmission case 17 via a rear axle case 19, and a left and right brake mechanism 563 that brakes the left and right rear traveling units 4 in the transmission case 17.
  • left and right brake pedals 35 for braking the left and right brake mechanisms 563 are disposed in front of the control seat 8 of the traveling machine body 2, the pair of brake mechanisms 563 are operated.
  • the left and right brake pedals 35 and the left and right brake mechanisms 563 are linked to each other via a brake link body 730, and the brake cylinders 730 correspond to the left and right brake link bodies 730 via a rope member 731. Since the 630 is interlocked and connected, the brake cylinder 630 can be connected to the mechanical connection structure from the brake pedal 35 to the brake mechanism 563 via the cord member 731. For this reason, the structure for operating the left and right brake mechanisms 563 manually and automatically can be managed mainly by a mechanical connection structure, and can be simplified and made compact and resistant to failure.
  • a first interchangeable member 733 is provided between the left and right brake link bodies 730 and the left and right brake pedals 35 so as not to follow the brake pedal 35 when the brake mechanism 563 is operated by the brake cylinder 630.
  • a second interchangeable member 736 that does not follow the brake cylinder 630 when the brake mechanism 563 is operated by the brake pedal 35 is provided.
  • the brake pedal 35 on one side does not follow up inadvertently when the automatic brake is activated.
  • the brake pedal 35 is depressed, an unnecessary load is applied to the brake cylinder 630 and the brake cylinder 630 is not damaged. Accordingly, the structure for manually and automatically operating the left and right brake mechanisms 563 is mainly organized by a mechanical connection structure, and the compatibility between the manual operation structure and the automatic operation structure can be realized easily and reliably. .
  • the steering column 32 is erected in such a state that the dashboard 33 is supported by a vertically long board support plate 308 erected on the front side inside the cabin 7 and embedded in the rear side of the dashboard 33.
  • a vertically long handle shaft (not shown) is supported in the steering column 32.
  • the upper end side of the handle shaft protrudes upward from the upper surface of the steering column 32.
  • a steering handle 9 having a substantially round shape in plan view is attached to the upper end side of the handle shaft.
  • the front end side of the vertically long steering shaft 740 is connected to the lower end side of the handle shaft through a universal joint.
  • An operation shaft 742 of a power steering hydraulic mechanism 621 supported on the lower side of the board support plate 308 is connected to the proximal end side of the steering shaft 740 via a universal joint 741.
  • the power steering hydraulic mechanism 621 of the embodiment is located in the upper front part of the transmission case 17 (near the position directly above the power transmission shaft 29).
  • the power steering hydraulic mechanism 621 is operated according to the operation amount (rotation amount), and the steering hydraulic cylinder 622 for power steering (see FIG. 14). ) Is driven, and the steering angle (steering angle) of the left and right front wheels 3 is changed.
  • an inspection opening 745 communicating with the opening 743 of the board support plate 308 is further formed in the floor plate 40 between the board support plate 308 and the control seat 8.
  • the inspection opening 745 faces the upper surface of the mission case 17 (the front lid member 491 and the front transmission case 112) located below.
  • the inspection opening 745 is detachably blocked by covering a lid cover plate 746 having a rectangular shape in plan view from above and fastening with a bolt.
  • a floor mat (not shown) is laid on the floor plate 40 attached to the lid cover plate 746.
  • a rear wheel differential gear mechanism 506 that transmits a driving force to the left and right rear wheels 4 is disposed.
  • the rear wheel differential gear mechanism 506 includes a ring gear 559 that meshes with a pinion 558 provided at the rear end of the auxiliary transmission shaft 546, a differential gear case 560 provided in the ring gear 559, and a pair of differential outputs extending in the left-right direction. And a shaft 561.
  • the differential lock shaft 755 and the differential lock fork 754 are provided with a pair of left and right cam members 761, 762 for converting a rotational force into a sliding force, arranged side by side in the axial direction of the differential lock shaft 755.
  • the left and right cam members 761 and 762 are in sliding contact with the V-shaped cam portions 763 and 764 and V-shaped cam portions 763 and 764 that are formed in V-shaped cutouts on the left and right ends of the base end boss body 756 of the differential lock fork 754. In this way, cam follower pins 765 and 766 that project from the differential lock shaft 755 are provided.
  • upper and lower two left V-shaped cam portions 763 are formed at the left end portion of the proximal end boss body 756, and upper and lower two right V-shaped cam portions 764 are formed at the right end portion of the proximal end boss body 756.
  • the upper and lower two left V-shaped cam portions 763 are positioned at the left end of the base boss body 756 with a phase difference of 180 degrees from each other, and the upper and lower two right V-shaped cam portions 764 have a phase difference of 180 degrees from each other. It is located at the right end of the proximal boss body 756.
  • the left cam follower pin 765 passes through the differential lock shaft 755 and is in sliding contact with both the upper and lower left V-shaped cam portions 763.
  • the right cam follower pin 766 passes through the differential lock shaft 755 and is in sliding contact with both the upper and lower right V-shaped cam portions 764.
  • the left and right V-shaped cam portions 763, 764 are formed symmetrically on the proximal boss body 756 of the differential lock fork 754.
  • the left and right cam follower pins 765 and 766 are provided on the differential lock shaft 755 with a phase difference in the circumferential direction.
  • the rotation direction when the differential lock shaft 755 is rotated clockwise in FIG. 29 is defined as the lock rotation direction, and the rotation when the differential lock shaft 755 is rotated counterclockwise in FIG.
  • the left cam follower pin 765 is positioned slightly downstream of the right cam follower pin 766 in the lock rotation direction.
  • An opening 759 is formed at the center of the base end boss body 756 of the differential lock fork 754.
  • a sliding restriction pin 767 is attached to a location corresponding to the opening 759 of the proximal end boss body 756 in the differential lock shaft 755.
  • the right cam follower pin 766 abuts on the apex portion 764a of the right V-shaped cam portion 764, so that the differential lock fork 754 and the differential lock clutch 753 can no longer move in the locking direction and are held in the locked position. That is, the left cam member 761 moves the differential lock clutch 753 to the locked position via the differential lock fork 754, and the right cam member 762 holds the differential lock fork 754 and the differential lock clutch 753 in the locked position.
  • the left and right cam follower pins 765 and 766 are rotated in the unlocking rotation direction.
  • the left cam follower pin 765 moves away from the front inclined portion 763b of the left V-shaped cam portion 763.
  • the right cam follower pin 766 contacts the rear inclined portion 766c of the right V-shaped cam portion 766 and relatively slides along the rear inclined portion 766c in the direction away from the apex angle portion 766a.
  • the left cam follower pin 765 contacts the apex portion 765a of the left V-shaped cam portion 765, so that the diff lock fork 754 and the diff lock clutch 753 can no longer move in the unlock direction and are held in the unlock position. . That is, the right cam member 762 moves the differential lock clutch 753 to the unlock position via the differential lock fork 754, and the left cam member 761 holds the differential lock fork 754 and the differential lock clutch 753 at the unlock position.
  • a differential mechanism that transmits the speed change power to the left and right rear running portions 4 of the traveling machine body 2 in the transmission case 17 that changes the power of the engine 5.
  • a differential lock fork that controls a differential lock body 753 that can pivotally support a horizontally long differential lock shaft 755 in the mission case 17 so as to be rotatable. 754 is attached to the differential lock shaft 755, and the differential lock shaft 755 and the differential lock fork 754 are provided with a pair of cam members 761 and 762 arranged in the axial direction of the differential lock shaft 755.
  • the differential lock body 753 is locked by the cam member 761 via the differential lock fork 754.
  • a biasing member 758 for biasing the differential lock fork 754 in the unlocking direction is attached to the differential lock shaft 755, and the differential lock body 753 is unlocked by the other cam member 762 via the differential lock fork 754. Since the unlocking position is defined by the one cam member 761, when the differential lock body 753 is not locked, the differential lock body 753 is moved by the action of the biasing member 758. It is easy to hold in the appropriate unlocking position.
  • FIG. 14 The left and right rear axle cases 19 include a fixed side case 771 connected to the left and right outer surfaces of the transmission case 17 (rear transmission case 113), and a sliding side case 772 fitted in the fixed side case 771 so as to be slidable left and right. ing.
  • the rear axle 20 is rotatably inserted in the sliding side case 772.
  • the planetary reduction mechanism 773 includes a sun gear 774 fixed to the differential output shaft 561, a holder 775 that rotatably supports a plurality of final gears 562 on the same radius, and a fixed side case 771 near the rear transmission case 113.
  • An annular gear 776 fixed to the inner peripheral surface is provided.
  • the sun gear 774 meshes with each final gear 562 pivotally supported by the holder 775 from the inside of the radius.
  • Internal teeth formed on the inner peripheral surface of the annular gear 776 mesh with each final gear 562 from the radially outer side.
  • the holder 775 is integrally formed with an output cylinder shaft 777 that is positioned concentrically with the differential output shaft 561 and extends outward in the left and right directions.
  • the base portion of the output cylinder shaft 777 is rotatably supported on the inner peripheral portion on the base end side of the fixed case 771.
  • the output cylinder shaft 777 is spline fitted to the left and right inner end sides of the rear axle 20 so as to be slidable to the left and right but not to be relatively rotatable.
  • a lock cylinder 781 that prevents the rotation of 772 is attached in a detachable manner in a posture parallel to the rear axle 20 and distributed in the front-rear direction.
  • a tread adjusting hydraulic cylinder 645 is disposed on the front outer surface side of the fixed side case 771
  • a lock cylinder 781 is disposed on the rear outer surface side of the fixed side case 771.
  • the cylinder portion 778 of the tread adjusting hydraulic cylinder 645 is bolted to the front outer surface side of the fixed case 771.
  • a piston portion 779 is fitted into the cylinder portion 778 of the tread adjusting hydraulic cylinder 645 so as to be slidable left and right.
  • the distal end side (left and right outer end sides) of the piston portion 779 is coupled to the connecting frame body 780 fixed to the distal end side (left and right outer end sides) of the sliding side case 772.
  • the cylinder portion 782 of the lock cylinder 781 is bolted to the rear outer surface side of the fixed case 771.
  • a locking shaft 783 serving as a piston portion is fitted into the cylinder portion 782 of the lock cylinder 781 so as to be slidable left and right. Similar to the piston portion 779 of the tread adjusting hydraulic cylinder 645, the distal end side (left and right outer end sides) of the detent shaft 783 is coupled to the connecting frame body 780 at the distal end side of the sliding side case 772.
  • the tread adjusting hydraulic cylinder 645 and the lock cylinder 781 with respect to the left and right rear axle cases 19 are configured symmetrically with respect to the transmission case 17 (rear transmission case 113) in plan view (see FIG. 30).
  • the sliding side case 772 and the rear axle 20 are slid left and right through the connecting frame body 780, and the left and right rear axle cases 19 is extended and contracted horizontally as a whole.
  • the tread between the left and right rear wheels 4 becomes longer or shorter.
  • the sliding side case 772 is connected by the connecting frame body 780. Is held non-rotatable. As a result, the sliding case 772 is prevented from being rotated due to the rotation of the rear wheel 4 (rear axle 20).
  • the lock pin 786 is inserted into the cylindrical body 785 with the head portion 786a facing the detent shaft 783 and a compression coil spring 787 fitted on the shaft portion 786b. Therefore, the compression coil spring 787 always urges the lock pin 786 toward the outer peripheral surface of the detent shaft 783 by its own elastic urging force.
  • the detent shaft 783 is formed with a plurality of detent grooves 784 (six in the embodiment). For this reason, in the embodiment, the protruding length of the sliding side case 772 (the length of the rear axle case 19) can be set in a plurality of stages (six stages in the embodiment).
  • the lock pin 786 When the rear axle case 19 is changed to a predetermined length by the expansion and contraction of the tread adjusting hydraulic cylinder 645, the lock pin 786 is fitted into the detent groove 784 corresponding to the predetermined length. In this state, the left and right slide of the rotation prevention shaft 783 is prevented, and the protruding posture of the rear axle case 19 is maintained.
  • the head 786a of the lock pin 786 slides in contact with the crests and the detent grooves 784 on the outer peripheral surface of the detent shaft 783, and enters the crests and the detent grooves 784.
  • the lock pin 786 moves in and out of the cylindrical body 785.
  • the rear axle cases 19 provided on the left and right sides of the transmission case 17 are fixed to the fixed case 771 connected to the transmission case 17 and the fixed case 771 to the left and right.
  • a work vehicle that includes a sliding side case 772 that is slidably inserted, and that can change a tread between the left and right rear traveling portions 4 provided in the left and right sliding side cases 772, the sliding side A tread adjusting hydraulic cylinder 645 that slides the case 772 to the left and right; and a lock cylinder 781 that prevents the sliding side case 772 interlocking with the rear traveling unit 4; and the tread adjusting hydraulic cylinder 645 and the lock cylinder 781 is attached to the front and rear of the rear axle case 19 so as to be detachable.
  • the tread adjustment hydraulic cylinder 645 and the lock cylinder 781 are connected to the rear axle. If it is not attached to the case 19, it is sufficient.
  • the rear axle case 19 can have a common structure regardless of differences in specifications with and without tread change, and various costs such as manufacturing costs, management costs, and transportation costs can be reduced.
  • each rear axle case 19 the tread adjusting hydraulic cylinder 645 and the piston portions 779 and 783 of the lock cylinder 781 are connected to a connecting frame body 780 fixed to the sliding side case 772, and the tread adjusting hydraulic pressure is set. Since the cylinder 645 and the lock cylinder 781 are symmetrically configured, the tread adjusting hydraulic cylinder 645 mounted on each rear axle case 19 can be structured in common and can be mounted on each rear axle case 19. The common structure of the lock cylinder 781 can also be achieved. For this reason, it is possible to further reduce various costs such as manufacturing costs, management costs, and transportation costs.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Body Structure For Vehicles (AREA)
  • Arrangement And Driving Of Transmission Devices (AREA)

Abstract

L'objet de la présente invention est de permettre à la structure d'un carter d'essieu arrière d'être partagée entre une conception présentant des variations de bande de roulement et une conception ne présentant pas de variations de bande de roulement dans un engin de chantier tel qu'un tracteur. Des carters d'essieu arrière (19) disposés sur les côtés gauche et droit d'un carter de boîte de vitesses (17) sont constitués d'un carter côté sécurisé (771) relié au carter de boîte de vitesses (17), et d'un carter côté coulissant (772) monté dans le carter côté sécurisé (771) de manière à être capable de coulisser à gauche et à droite. La bande de roulement entre des parties de déplacement arrière (4) gauche et droite disposées sur les carters côté coulissant (772) gauche et droite est conçue de manière à être variable. L'invention concerne également des cylindres hydrauliques de réglage de bande de roulement (645) permettant de faire coulisser les carters côté coulissant (772) vers la gauche et vers la droite, et des cylindres de verrouillage (781) permettant d'inhiber la rotation conjointe des carters côté coulissant (772) interconnectés avec les parties de déplacement arrière (4). Les cylindres hydrauliques de réglage de bande de roulement (645) et les cylindres de verrouillage (781) sont fixés amovibles de façon à être distribués vers l'avant et vers l'arrière des carters d'essieu arrière (19).
PCT/JP2015/078378 2014-10-15 2015-10-06 Engin de chantier Ceased WO2016060025A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2014-211139 2014-10-15
JP2014211139A JP2016078601A (ja) 2014-10-15 2014-10-15 作業車両

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WO2016060025A1 true WO2016060025A1 (fr) 2016-04-21

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PCT/JP2015/078378 Ceased WO2016060025A1 (fr) 2014-10-15 2015-10-06 Engin de chantier

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021183076A1 (fr) * 2020-03-12 2021-09-16 Base Studio Arge Ve Teknoloji Sanayi Anonim Sirketi Ensemble de verrouillage différentiel

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH092013A (ja) * 1995-06-23 1997-01-07 Ishikawajima Shibaura Mach Co Ltd 伸縮式車軸の自動ロック機構
JP2000074187A (ja) * 1998-08-28 2000-03-07 Kanzaki Kokyukoki Mfg Co Ltd 作業車両におけるデフロック操作装置
JP2002067657A (ja) * 2000-09-04 2002-03-08 Yanmar Agricult Equip Co Ltd 空気調和機を取り付けるキャビンの構造
JP2002106712A (ja) * 2000-09-27 2002-04-10 Iseki & Co Ltd リニアシフト型変速操作装置

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH092013A (ja) * 1995-06-23 1997-01-07 Ishikawajima Shibaura Mach Co Ltd 伸縮式車軸の自動ロック機構
JP2000074187A (ja) * 1998-08-28 2000-03-07 Kanzaki Kokyukoki Mfg Co Ltd 作業車両におけるデフロック操作装置
JP2002067657A (ja) * 2000-09-04 2002-03-08 Yanmar Agricult Equip Co Ltd 空気調和機を取り付けるキャビンの構造
JP2002106712A (ja) * 2000-09-27 2002-04-10 Iseki & Co Ltd リニアシフト型変速操作装置

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021183076A1 (fr) * 2020-03-12 2021-09-16 Base Studio Arge Ve Teknoloji Sanayi Anonim Sirketi Ensemble de verrouillage différentiel

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