WO2002011519A1 - Power transmission structure for small tillers - Google Patents

Abstract

A power transmission structure capable of attempting miniaturization and weight reduction of small tillers. A small tiller comprising a transmission case bent substantially in a doglegged shape as seen in a side view and interlocked with a prime mover, a traveling section disposed in the front of the transmission case, and a tilling section disposed in the rear of the transmission case, wherein the drive shaft of the transmission case is interlocked with the output shaft of the prime mover through a speed change mechanism, and an axle for driving the traveling section and a tilling shaft for driving the tilling section are individually interlocked with the drive shaft of the transmission case, so that the power from the prime mover is transmitted from a single drive shaft of the transmission case to the traveling section and tilling section.

Description

 Specification

 Power transmission structure of small cultivator

 The present invention relates to a power transmission structure for a small cultivator. Background art

 The conventional small cultivator has a prime mover that is linked to a mission case that is bent in the shape of a letter when viewed from the side, and an axle that extends to the left and right width directions at the front end of the mission case is rotatable. Attach the wheels to the left and right ends of the axle to form a running part, and attach the tilling shaft extended in the left and right width direction to the rear end of the mission case so that it can rotate freely. A plurality of tilling claws extended in the radial direction were attached to the outer periphery of the cultivator to form a tilling work area.

 Further, in the conventional small cultivator, a driving shaft for driving the driving unit and a driving shaft for tilling work for driving the tilling work unit are provided in the mission case. In the conventional small cultivator, the drive shaft for traveling and the drive shaft for tilling work are linked to the output shaft of the prime mover via a transmission mechanism arranged above the mission case.

In addition, the mission case is composed of a running part-side case body extending from the bent portion in a front-to-low and rear-to-back slope, and a tilling work part-side case structure extending from the bent portion to the front-to-back and back-to-back slope. In addition, the angle between the running-part-side case component and the tilling-working-part-side case component is bent at an acute angle equal to or less than a right angle. However, in the conventional small cultivator described above, a drive shaft for driving a traveling unit and a drive shaft for tilling work for driving a tilling work unit are provided in a mission case, and a prime mover is mounted on each drive shaft. Because the output shafts of the motors were linked to each other via a speed change mechanism, the power transmission structure from the output shaft of the prime mover to each drive shaft became complicated, and assembly work and maintenance could not be carried out smoothly.

 In addition, in the conventional small cultivator, since the transmission mechanism is disposed above the transmission case, it has been difficult to reduce the height of the small cultivator and reduce the size.

 Further, in the above-mentioned conventional small cultivator, since the transmission case is formed by bending the transmission case at an acute angle, the position of the center of gravity of the small cultivator becomes high, and there is a possibility that it may be difficult to stably travel in the field. . Disclosure of the invention

 In view of this, the present invention relates to an engine in which a transmission case bent substantially in a letter shape in a side view is interlockedly connected to a prime mover, a traveling section is disposed at a front portion of the transmission case, and a tilling work section is disposed at a rear portion of the transmission case. In the small tiller, the drive shaft of the mission case is linked to the output shaft of the prime mover via a speed change mechanism, and the axle for driving the traveling unit is driven by the drive shaft of the mission case. The tilling shafts for driving the parts are linked to each other, and the power of the prime mover is transmitted from one drive shaft of the mission case to the traveling part and the tilling work part.

Further, according to the present invention, a drive shaft is disposed at a bent portion of a transmission case which is bent substantially in a side view in a side view, and a transmission mechanism is disposed at a position forward of the drive shaft. did.

 In addition, according to the present invention, the mission case bent substantially in a letter shape when viewed from the side includes a traveling-portion-side case structure extending in an inclined shape having a low front and rear height from a bent portion; The tilling work part side case structure extended to a low slope was bent at a right angle or more. BRIEF DESCRIPTION OF THE FIGURES

 【Figure 1】

 The left view which shows the small cultivator which concerns on this invention.

 【Figure 2】

 FIG.

 [Figure 3]

 FIG. 3 is a plan sectional view showing the inside of the mission case.

 [Fig. 4]

 The same left view.

 [Figure 5]

 FIG. 3 is a cross-sectional plan view showing a transmission mechanism.

 [Fig. 6]

 FIG. 3 is a plan sectional view showing a traveling unit.

 [Fig. 7]

 Sectional plan view showing a tilling work part. BEST MODE FOR CARRYING OUT THE INVENTION

The small-sized cultivator according to the present invention has a prime mover formed by bending a prime mover into a substantially rectangular shape in side view. In addition, the traveling case is arranged at the front of the mission case and the tilling work unit is arranged at the rear of the mission case.The small cultivator according to the present invention is an output shaft of a prime mover. In addition, the drive shaft of the mission case is interlocked with the drive shaft of the mission case via a speed change mechanism, and the axle for driving the traveling unit and the tilling shaft for driving the tilling work unit are shifted to the drive shaft of the mission case. Linked and linked.

 The power of the prime mover is transmitted to the drive shaft of the mission case, and then directly transmitted from one drive shaft of the mission case to the axle of the traveling unit and the tilling shaft of the tilling work unit.

 Therefore, the small cultivator according to the present invention can simplify the structure for transmitting power, improve the assembly workability and maintenance of the mission case, and can improve the mission case and, consequently, the small cultivator. It can be smaller and lighter.

 In addition, in the small tiller according to the present invention, the drive shaft is provided at the bent portion of the mission case, and the transmission mechanism is provided at a position in front of the drive shaft.

 Therefore, the small cultivator according to the present invention can reduce the height of the mission case, reduce the vehicle height of the small cultivator itself, and reduce the size and weight of the small cultivator itself. And the running stability can be improved by lowering the position of the center of gravity.

Further, in the small cultivator according to the present invention, the mission case includes a running-portion-side case member extending from a bent portion to a front-rear-lower-inclined shape, and a mission-case extending from a bent portion to a front-rear-higher-lower-inclined shape. The tilling work part side case body is bent at a right angle or more. Therefore, the small cultivator according to the present invention can reduce the height of the mission case, reduce the vehicle height of the small cultivator itself, and reduce the size and weight of the small cultivator itself. As a result, the running stability can be improved by lowering the position of the center of gravity.

 Specific embodiments of the present invention are described as follows.

 As shown in FIG. 1 and FIG. 2, a small cultivator 1 according to the present invention has a motor unit 3 disposed at a position in front of a mission case 2 formed by bending a substantially rectangular shape in a side view. The traveling part 4 is arranged at the lower front part of the transmission case 2, the tilling work part 5 is disposed at the lower rear part of the transmission case 2, and the operation part 6 is disposed above the transmission case 2. Has been established. As shown in FIGS. 1 and 2, the prime mover unit 3 has a prime mover mounting base 取 付 け mounted on the lower front side of the mission case 2, a prime mover 8 is mounted on the prime mover mounting base 7, and a prime mover 8 is mounted on the prime mover 8 The fuel tank 9 is installed in the tank. In the figure, reference numeral 10 denotes a bumper that also serves as a front weight.

 As shown in FIGS. 1 and 2, the traveling part 4 is rotatably mounted with an axle 11 extending in the left-right width direction at a lower portion on the front side of the mission case 2 and is rotatably attached to the left and right ends of the axle 11. Installing wheels 1 2 it each. The detailed structure of the traveling section 4 will be described later.

As shown in Fig. 1 and Fig. 2, the tilling work part 5 has a tilling shaft 13 extended in the left and right width direction at the rear lower part of the mission case 2 rotatably mounted. The tilling claw 14 extended in the radial direction is interlocked and connected, and the front end of the tilling cover 16 that covers the upper part of the rotation locus 15 of the tilling claw 14 is attached to the middle part of the mission case 2. At the rear end of the cultivation cover 16, a cultivation depth adjustment bar 17 is attached so as to be able to move up and down. At the rear end, a rubber mud jump prevention cover 18 is suspended. In the figure, reference numeral 19 denotes a support bracket for supporting the tillage adjusting bar 17. The detailed structure of the tilling work section 5 will be described later.

 As shown in FIGS. 1 and 2, the operation unit 6 has a substantially portal-shaped handle 20 in a plan view, attached to the middle of the transmission case 2 in a front-to-back and rear-to-back slope, and an upper end of the handle 20. A deadman clutch lever 21 is disposed on the vehicle, and a speed change lever 22 is disposed in front of the handlebar 20 in a front-rear-low-high inclination.

 The speed change lever 22 has a substantially L-shaped speed change arm 23 attached to the base end thereof, and the front end of the speed change arm 23 is extended and retracted in the middle of the mission case 2 in the left-right width direction. The shift lever is movably mounted on the right end of the support shaft 24 so as to be rotatable left and right, and can be shifted along the guide groove 26 formed in the guide plate 25 mounted on the upper part of the mission case 2. I am able to do it.

 As shown in Figs. 1 and 4, the mission case 2 includes a traveling-side case structure 28 that extends from the bent portion 27 in a slanting manner at the front and rear, and a slant from the bent portion 2 to the front and rear high and low. And the running part side case member 28 and the tilling work part side case body 29 are bent at an angle of approximately a right angle or more and viewed from the side. It is formed in the shape of an approximate letter.

The input case 30 is rotatably mounted on the front upper portion of the bent portion 27 with the input shaft 30 extended in the left-right width direction protruding toward the left side of the input case 2. 30 is linked to the output shaft (not shown) of the prime mover 8 via the transmission belt 33 inside the belt cover 31. . In FIG. 4, reference numeral 32 denotes a transmission pulley attached to the left end of the input shaft 30, and reference numeral 33 denotes a transmission belt for interlocking the output shaft of the motor 8 and the input shaft 30 of the transmission case 2.

 In the mission case 2, a drive shaft 34 extending in the left-right width direction is rotatably attached to the bent portion 27, and the drive shaft 34 has an input shaft interlocked with the output shaft of the prime mover 8. 30 is interlocked via a speed change mechanism 35.

The transmission mechanism 35 is a bent portion 27 of the mission case 2 and is accommodated and disposed at a position in front of the drive shaft 34, and has the following configuration. That is, as shown in FIGS. 3 to 5, the transmission mechanism 35 includes a low-speed forward mode for advancing the aircraft at a low speed and a low-speed advancing mode for advancing the aircraft at a low speed on the upper front side of the bent portion 27 of the transmission case 2. Running tilling shifter 36 for switching to the tilling work mode for driving the tilling work unit 5, forward and backward for switching between the high speed forward mode for moving the aircraft forward at high speed and the low speed reverse mode for moving the aircraft backward at low speed. The right and left shifters 37 and 37 are attached to the right ends of the shifters 36 and 37, respectively, to form locking recesses 38 and 39, respectively. One of a pair of front and rear engaging portions 40 and 41 formed by crushing the outer peripheral portion of the transmission arm 23 at the base end of the transmission lever 22 engages with one of the locking concave portions 38 or 39. I am trying to do it. In the figure, 42 and 43 are detent grooves formed on the outer periphery of the shifters 36 and 37, 44 and 45 are detent poles engaged with the detent grooves 42 and 43, and the transmission mechanism 35 is a transmission lever. When the first 22 is moved upward along the guide groove 26, the front engaging portion 40 of the shifting arm 23 of the shifting lever 22 runs. When the transmission lever 22 is operated to the right along the guide groove 26 while engaging with the locking recess 38 of the tilling shifter 36, the tilling shifter 36 moves rightward. When the speed change lever 22 is operated downward along the guide groove 26, the rear engagement portion 41 of the speed change arm 23 of the speed change lever 22 engages with the engagement recess 39 of the forward / reverse shift shifter 37. When the speed change lever -22 is operated in the left-right direction along the guide groove 26, the forward / reverse shift shift 37 moves in the left-right direction.

 On the other hand, the transmission mechanism 35 has a transmission gear 46 spline-fitted to the middle part of the input shaft 30 so as to be slidable toward the left and right width directions.

 The running tilling shifter Yuichi 36 attached the connecting hook 47 downward in the middle, engaged the connecting groove 47 formed in the outer periphery of the transmission gear 46 with the tip of the connecting hook 47, and traveled. A transmission gear 46 moves along the input shaft 30 in conjunction with the tilling shifter 36, and a forward / reverse switching gear 49 is rotatable in the middle of the forward / rearward shifter 37. The forward / reverse switching gear 49 and the transmission gear 46 are loosely fitted.

 The transmission mechanism 35 has a transmission shaft 50 extended in the left-right width direction rotatably attached to the front lower portion of the bent portion 27 of the mission case 2, and a small-diameter traveling transmission gear is provided in the middle of the transmission shaft 50. 5, a low-speed gear 52 is attached to the right end of the transmission shaft 50, and a large-diameter tilling transmission gear 53 having the same diameter as the low-speed gear 52 is freely rotatable at the right end of the transmission shaft 50. It is fitting.

 The low-speed gear 52 and the large-diameter tilling transmission gear 53 can be engaged with a transmission gear 46 spline-fitted to the input shaft 30.

Further, the transmission mechanism 35 mounts a large-diameter traveling transmission gear 54 in the middle of the drive shaft 34 and rotates a tilling drive gear 55 on the right side of the drive shaft 34. A small-diameter tilling transmission gear 56 is attached to the right end of the tilling drive gear 55, and a traveling drive gear 57 is attached to the left end of the drive shaft 34. Is coupled to a small-diameter traveling transmission gear 51 formed on the transmission shaft 50 and is also connectable to a forward-reverse switching gear 49 loosely fitted to the forward-reverse shift shifter 37. The small-diameter tilling transmission gear 56 is And a large-diameter tilling transmission gear 53 attached to the driving unit 50. Further, the traveling drive gear 57 is interlocked to the axle 11 of the traveling unit 4 via a traveling transmission chain 58. It is linked to the tilling shaft 13 of the tilling work unit 5 via a tilling transmission chain 59.

 The speed change mechanism 35 is configured as described above, and the speed is shifted as follows by operating the speed change lever 22.

 That is, when the speed change mechanism 35 is set to the neutral state with the speed change lever 22 upright, the input shaft 30 interlockingly connected to the prime mover 8 idles, and the traveling section 4 and the tilling work section 5 stop.

Further, the speed change mechanism 35 moves the speed change lever 22 once upward along the guide groove 26 and then moves to the right side to enter the low-speed forward mode. In the low-speed forward mode, the transmission As a result, the transmission gear 46 moves rightward along the input shaft 30 so that the transmission gear 46 and the low-speed gear 52 are combined, and the power of the prime mover 8 is transmitted from the transmission gear 46 via the input shaft 30 to the low-speed gear. The transmission is transmitted to the small-diameter traveling transmission gear 51 via the transmission shaft 50 from the low-speed gear 52, and transmitted from the small-diameter traveling transmission gear 51 to the large-diameter traveling transmission gear 54, and transmitted to the large-diameter traveling transmission. The power is transmitted from the gear 54 to the traveling drive gear 57 via the drive shaft 34, and the traveling drive chain 57 is transmitted from the traveling drive gear 57. The transmission is transmitted to the axle 11 of the traveling section 4 via the pin 58, and the axle 11 of the traveling section 4 rotates at a low speed, and the aircraft advances at a low speed. In the low-speed forward mode, the transmission gear 46 and the large tilling transmission gear 53 are not engaged, and the tilling work unit 5 is stopped.

 Further, when the speed change mechanism 35 is moved to the right along the guide groove 26, the speed change mechanism 35 enters a tilling operation mode. In this tilling operation mode, the transmission gear 46 is driven by the input shaft 30 along with the traveling tilling shift 36. And the transmission gear 46 and the low-speed gear 52 and the large-diameter tilling transmission gear 53 are combined, and the power of the prime mover 8 is transmitted from the transmission gear 46 through the input shaft 30 to the low-speed gear 52 and The power transmitted to the large-diameter tilling transmission gear 53 and transmitted to the low-speed gear 52 is transmitted from the low-speed gear 52 to the transmission shaft 50, the small-diameter traveling transmission gear 51, and the large-diameter traveling in the same manner as in the low-speed forward mode described above. The power is transmitted to the transmission gear 54, the drive shaft 34, the traveling drive gear 57, the traveling transmission chain 58, and the axle 11, and the axle 11 of the traveling unit 4 rotates at a low speed, so that the aircraft advances at a low speed. The power transmitted to the dynamic gear 53 has a large diameter Transmission from the tilling transmission gear 53 to the small-diameter tilling transmission gear 56, transmission from the small-diameter tilling transmission gear 56 to the tilling drive gear 55, The power is transmitted to the tilling shaft 13, and the tilling shaft 13 of the tilling work unit 5 rotates to perform the tilling work.

Further, the speed change mechanism 35 enters the high-speed forward mode by moving the speed-change lever 22 once downward along the guide groove 26 and then to the left, and in such a high-speed forward mode, the speed change mechanism The forward / reverse switching gear 49 moves to the left, and the forward / reverse switching gear 49 and the large-diameter traveling transmission gear 54 are directly engaged (ie, without being reduced by the low-speed gear 52). The power of the prime mover 8 is transmitted from the transmission gear 46 to the forward / reverse switching gear 49 via the input shaft 30 and is transmitted from the forward / reverse switching gear 49 to the large-diameter traveling transmission gear 54 at an increased speed. From the radial transmission gear 54 to the traveling drive gear 57 via the drive shaft 34, and from the traveling drive gear 57 to the axle 11 of the traveling section 4 via the traveling transmission chain 58. The axle 11 rotates at high speed and the aircraft advances at high speed. In the high-speed forward mode, the transmission gear 46 and the large tilling transmission gear 53 are not engaged, and the tilling work unit 5 is stopped.

 On the other hand, when the speed change mechanism 35 moves the speed change lever 22 once downward along the guide groove 26 and then moves to the right side, the low speed reverse mode is established. As a result, the forward / reverse switching gear 49 moves rightward, and the forward / reverse switching gear 49 and the low speed gear 52 are brought into a combined state, and the power of the prime mover 8 is transmitted from the transmission gear 46 via the input shaft 30 to the forward / reverse switching gear. And transmitted to the low-speed gear 52 from the forward / reverse switching gear 49 at a reduced speed (that is, power is transmitted from the transmission gear 46 to the low-speed gear 52 in a state reversed from the low-speed forward mode). ), Transmitted from the low-speed gear 52 to the small-diameter traveling transmission gear 51 via the transmission shaft 50, transmitted from the small-diameter traveling transmission gear 51 to the large-diameter traveling transmission gear 54, and transmitted from the large-diameter traveling transmission gear 54. It is transmitted to the traveling drive gear 57 via the drive shaft 34. And transmitted to the axle 1 1 of the traveling portion 4 via the traveling transmission chain 58 from the traveling drive gear 57, drive shaft 1 1 of the travel unit 4 body rotates at a low speed to a low speed reverse. In the low-speed reverse mode, the transmission gear 46 and the large tilling transmission gear 53 are not engaged, and the cultivating work unit 5 is stopped.

As described above, the small cultivator 1 according to the present embodiment includes the prime mover 8 The drive shaft 34 of the mission case 2 is interlocked to the output shaft via the speed change mechanism 35, and the axle 12 and the tilling work unit 5 for driving the traveling unit 4 are driven by the drive shaft 34 of the mission case 2. The power of the prime mover 8 is transmitted to the drive shaft 34 of the mission case 2 and then from one drive shaft 34 to the axle 11 of the traveling unit 4. Is transmitted directly to the tilling shaft 13 of the tilling work section 5, which simplifies the structure for power transmission and improves the assembly workability and maintenance of the mission case 2. At the same time, the size and weight of the mission case 2 and, consequently, the compact cultivator 1 can be reduced.

 In particular, in the small cultivator 1 according to the present embodiment, since the drive shaft 34 is disposed at the bent portion 27 of the mission case 2 and the transmission mechanism 35 is disposed at a position in front of the drive shaft 34, The height of the mission case 2 can be reduced, the height of the compact cultivator 1 can be reduced, and the compact cultivator 1 can be reduced in size and weight. Stability can be improved.

In addition, the small cultivator 1 according to the present embodiment includes a running case side case body 28 in which the mission case 2 is extended from the bent portion 27 in a slanting manner with a front low and a high height. The tilling work part side case structure 29, which is extended in an inclined shape, is bent while maintaining an angle of at least a right angle, and as shown in FIG. 4, the axis of the drive shaft 34 and the axle 12 Angle A between the imaginary center line L2 on the tilling work side connecting the axis of the drive shaft 34 and the axis of the tilling axis 13 with the imaginary center line L1 on the traveling side connecting the axis and the axis of the drive shaft 34 is a right angle or more than a right angle Therefore, the height of the mission case 2 can be reduced, and the vehicle height of the small cultivator 1 can be reduced. Conversion And the center of gravity is lowered, so that running stability can be improved.

 In particular, the small cultivator 1 according to the present embodiment is near the cultivation work side virtual center line L2 connecting the axis of the drive shaft 34 and the axis of the cultivation shaft 13, and more than the axis of the drive shaft 34. Since the speed change mechanism 35 is disposed at the front position, the size of the speed change mechanism 35 can be reduced, and also the height of the mission case 2 can be reduced, and the size of the small tiller 1 can be reduced. The height of the vehicle can be reduced, the size and weight of the small cultivator 1 can be reduced, and the running center can be improved because the position of the center of gravity is lowered.

 As shown in FIGS. 3, 4, and 6, the traveling unit 4 has an axle 11 at the lower end of the traveling unit side case structure 28 of the transmission case 2, and the axle 11 is A pair of left and right axles 60 and 61 rotatably supported at the lower left and right ends of the traveling unit side case component 28 of the case 2 are provided with a differential gear mechanism between the left and right axles 60 and 61. 62 is interposed.

 The differential gear mechanism 62 is rotatably and loosely fitted with a traveling driven gear 63 having a traveling transmission chain 58 wound around a left axle 60, and a pair of front and rear shaft supporting members is mounted on the right side surface of the traveling driven gear 63. Body 64, 64, and a support shaft 65 is rotatably mounted between the coaxial supports 64, 64. A pair of front and rear pinion gears (bevel gears) 66, 67 are mounted on the support shaft 65, while the left and right axles are mounted. A pair of left and right side gears (bepel gears) 68, 69 are attached to the base ends of the 60, 61, respectively, and the side gears 68, 69 and the pinion gears 66, 67 are combined. In the figure, reference numeral 70 denotes a guide ring inscribed in the outer peripheral surfaces of the shaft supports 64, 64.

Here, the traveling driven gear 63 is a side attached to the base end of the left axle 60. The gear 68 is rotatably supported by a boss 71. Therefore, the load of the traveling transmission chain 58 applied to the traveling driven gear 63 can be strongly received by the boss portion 71 of the side gear 68, and the traveling driven gear 63 can be prevented from falling or falling, and can be smoothly moved. Driving can be secured.

 The differential gear mechanism 62 has a differential opening mechanism 72. The differential lock mechanism 72 has a lock pawl 73 protruding from an inner peripheral portion of the traveling driven gear 63 at intervals in a circumferential direction and a left axle. A differential hook operating body 74 that engages with the hook pawl 73 is spline-fitted movably in the left-right direction in the middle of the hook 60, and an operation arm is mounted on the outer peripheral portion of the differential lock operating body 74. Attach the distal end of the operation arm 75 to the middle of the operation bar 76 that is attached to the case 2 so that it can move to the left and right. Is installed. In the figure, reference numeral 78 denotes an energizing spring.

 As shown in FIGS. 3, 4, and 7, the tilling work unit 5 includes a tilling claw rotation mechanism 79 that drives the tilling claw 14 forward and a tilling claw reversing mechanism 80 that drives the tilling claw 14 reversely. The tilling claw 14 in the left and right outer parts is rotated forward by the tilling claw forward rotation mechanism 79, while the cultivating claw 14 in the center part is reversed by the tilling claw reversing mechanism 80 to efficiently cultivate the field. I can do it.

The tilling claw forward rotation mechanism 79 supports the tilling shaft 13, which is extended in the left and right width direction, at the lower end of the tilling work section side case structure 29 of the mission case 2 by rotating itself, and At the center of shaft 13, a forward rotation tillage driven gear 81 with a cultivating transmission chain 59 is wound, and at the right and left ends of the tillage shaft 13, cylindrical claw support tubes 82, 83 are attached. The tilling claw 14 for forward rotation is detachably attached to the outer peripheral portions of the claw support cylinders 82 and 83 in the radial direction. In the figure, 84 is Bracket 85 is a fixing bolt and nut.

 The tilling claw reversing mechanism 80 holds the reversing shaft 86 extended in the left and right width direction at the lower end of the tilling work unit side case structure 29 of the mission case 2 at a constant interval along the tilling shaft 13. A reverse tilling driven gear 87, which is rotatably supported and has a tilling transmission chain 59 wound on the reverse rotation shaft 86, is attached. A pair of left and right intermediate drive gears 88, 89 are provided on both left and right ends of the reverse tilling driven gear 87. On the other hand, a pair of right and left reversing claw shafts 90 and 91 are freely rotatably fitted to the tilling shaft 13, and intermediate driven gears 92 and 93 are attached to the inner peripheral portions of the reversing claw shafts 90 and 91 respectively. The intermediate driven gears 92, 93 and the intermediate drive gears 88, 89 are combined, and further, cylindrical claw support cylinders 94, 95 are provided on the outer peripheral portion of the reversing claw shafts 90, 91 in the lateral width direction. The tilling claw 14 for reverse rotation is fitted in the outer circumference of the claw support cylinders 94 and 95 in the radial direction. That are removably attached towards. In the figure, 96 is a bracket, 97 is a fixing bolt ■ Nut, and 98 is a tension roller.

 Here, the claw support cylinders 94 and 95 are spline-fitted with the inverted claw shafts 90 and 91 at a position directly below the tillage claw 14. That is, the spline groove 99 formed in the outer peripheral portion of the reversing claw shafts 90 and 91 is extended to a position immediately below the tilling claw 14. Therefore, the reversing claw shafts 90 and 91 can be prevented from falling down, and the tilling claws 14 can be used for smooth tilling work.

In addition, since the spline grooves 99 of the reversing claw shafts 90, 91 extend to a position directly below the tilling claw 14, the claw support cylinders 94, 95 also extend toward the outside of the fuselage. The tilling claw 14 is also located on the outer side of the fuselage, but the tip of the tilling claw 14 for normal rotation is offset toward the inner side of the fuselage so that the tilling operation can be performed satisfactorily. I have to. Industrial applicability

 In the present invention, the drive shaft of the mission case is interlocked to the output shaft of the prime mover via a transmission mechanism, and the drive shaft of the mission case drives the axle and the tilling work unit for driving the traveling unit. The power of the prime mover is transmitted to the drive shaft of the mission case, and then from one drive shaft of the mission case to the axle of the traveling part. The power is transmitted directly to the tilling shaft of the tilling work section, which simplifies the structure for power transmission and improves the ease of assembly and maintenance of the mission case. As a result, the compact tiller can be made smaller and lighter.

 In addition, the drive shaft is arranged at the bending part of the mission case, and the transmission mechanism is arranged at the front position of the drive shaft. The height of the tiller can be reduced, the size and weight of the small tiller can be reduced, and running stability can be improved because the position of the center of gravity is lowered.

 In addition, the running part side case structure in which the mission case extends from the bent portion to the front-to-back and back-to-back slope, and the tilling work part-side case structure in which the bending case extends to the front-to-back and back-to-back slope. Since the body and the body are bent while maintaining an angle of more than a right angle, the height of the mission case can be reduced, and the height of the compact tiller can be reduced. As a result, it is possible to reduce the size and weight of the small cultivator and to improve the running stability because the position of the center of gravity is lowered.

Claims

 Scope of request.A motor case is linked to a transmission case that is bent in a substantially rectangular shape when viewed from the side, and a traveling section is arranged at the front of the transmission case and tilling is performed at the rear of the transmission case. In a small tiller equipped with a working unit,  The drive shaft of the mission case is interlocked to the output shaft of the prime mover via a speed change mechanism, and the axle for driving the traveling unit and the tilling shaft for driving the tilling work unit are connected to the drive shaft of the mission case. And a power transmission structure for a small cultivator, wherein the motive power of the prime mover is transmitted from one drive shaft of the mission case to the traveling section and the tilling work section. The drive shaft is disposed at a bent portion of the transmission case which is bent substantially in a side view as viewed from the side, and a transmission mechanism is disposed at a position forward of the drive shaft. Power transmission structure of small tiller. The mission case, which is bent in a substantially elliptical shape when viewed from the side, is composed of a traveling-side-side case structure that extends from the bent portion in a slanting manner at the front, rear, and rear, and a slant shape that extends from the bent portion to a front, rear, and high. The power transmission structure for a small tilling machine according to claim 1 or 2, wherein the tilling work unit side case component is bent while maintaining an angle of not less than a right angle.