JP2006192960A - Twin-wheel bicycle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a twin-wheel bicycle, obtaining stable cornering in high-speed running, and obtaining stable running on small projecting and recessed parts, and restraining sinking over a fixed size of two wheels when the road surface has large projecting and recessed parts to thereby maintain sure handling. <P>SOLUTION: This twin-wheel bicycle includes: a main frame 4 extended in the longitudinal direction to form the whole skeleton; and a two-wheel elevating support and restraining means 7 supporting two wheels at a space from each other in the axial direction to vertically move and restraining two wheels from sinking at the same time. The two-wheel elevating support and restraining means includes: a wheel support 11 supporting two wheels at a space in the axial direction at the other end of an elevating part 10 composed of a stationary body 8 and a pair of mover 9 independently moving vertically to the stationary body; energizing means 12 mounted between the stationary body and the movers and individually provided on the two wheels; and a sinking restraining means 20 formed of a fluid absorbing part and provided in a fluid passage connecting hydraulic dampers provided on the two wheels, individually and the cylinder chambers thereof. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a two-wheeled bicycle that has two front wheels or two rear wheels and is preferably used as an off-road bicycle such as a city run or a mountain bike.

  Bicycles with two front wheels have already been put into practical use for running stability and convenience of loading. In general, in a two-wheeled vehicle, the vehicle body is leaned inward to resist centrifugal force during turning, but it is necessary to exert centripetal force in cornering even in the front two-wheeled bicycle. Therefore, as shown in FIG. 16, the present inventor rotates a front frame e having a handle a and a steering shaft b at the upper portion and two front fork members d and d at the lower portion to the front end of the main frame f. By attaching the front wheels g, g pivotably supported in the steering axis direction to the lower portions of the front fork members d, d by the spring members h, the load received from the road surface can be increased or decreased. Accordingly, a front two-wheel bicycle in which the front wheels g and g can move up and down independently has been proposed (for example, see Patent Document 1).

  In this proposal, the spring member h absorbs and relaxes the shock at the time of riding and enhances the ride comfort, and at the time of turning, the front two wheels independently resist the elasticity of the spring member h, so that the vehicle body is similar to a normal motorcycle. The rider can lean and turn while facing the centrifugal force. Furthermore, when only one side of the front wheel g rides on a stone or the like on the road surface, or when it collides diagonally with a stepped portion such as a curbstone, the abutting side front wheel g is lifted to prevent the vehicle from falling over and balanced. it can.

JP 2003-811652 A

  However, when the brake is applied suddenly while driving or over a large obstacle on the road surface, the front two wheels that receive a large load from the road surface sink deeply at the same time, and at the next moment, the compressed spring member h reacts. As a result, the front frame e is flipped up and the rider is greatly shaken up and down. Therefore, it was found that there was room for improvement in terms of steering wheel operability and the ride comfort.

  Further, in order to improve this, it is conceivable to suppress the rider from swinging up and down by combining the spring member h with a damper device to form a shock absorber. However, if the movement of the front two wheels suspended independently is suppressed and the movement against the load change is delayed, for example, even if the rider leans the weight inward when turning, the vehicle body cannot sufficiently lean accordingly, especially Since cornering becomes difficult during high-speed driving, there is a risk of falling, and comfortable slalom driving is impossible. Further, when riding over small irregularities such as pebbles on the road surface, the vibration is transmitted to the rider without being absorbed, so that the ride comfort is poor and the steering operation becomes unstable.

  The present invention is based on the provision of a two-wheel lifting support / suppression means that suppresses simultaneous sinking of two wheels supported so as to be movable up and down. In addition to being able to ride stably and ride over, it is possible to maintain reliable handling of large road surface irregularities such as during off-road driving because the sinking of the two wheels or more is suppressed. The issue is the provision of twin-wheel bicycles.

  In order to achieve the above object, the invention according to claim 1 is a dual-wheel bicycle in which at least one of a front wheel or a rear wheel is constituted by two wheels spaced apart from each other on the left and right, and extends to the front and back to form a whole skeleton. And a two-wheel lifting support / suppression means for supporting the two wheels so as to be movable up and down at an axial interval and suppressing simultaneous sinking of the two wheels. The means includes a stationary body and the two wheels at the other end portion of the elevating portion that is formed of a pair of movable bodies that engage with the stationary body and at least the other end portion moves up and down independently of the stationary body. A wheel support member that is supported in an axially spaced manner; a biasing means that is mounted between the stationary body and the movable body so as to individually bias the two wheels downwardly; Cylinder cylinder with chamber and front A cylinder device comprising a piston rod extending from a piston sliding in the cylinder chamber is individually provided on the two wheels, the cylinder cylinder is attached to the stationary body, the piston rod is attached to the movable body, and both the cylinder chambers are joined. It is characterized by comprising a subsidence suppression means provided with a fluid absorption part that absorbs fluid and restricts the amount of absorption when the two wheels sink simultaneously in the fluid path.

  In the invention according to claim 2, the cylinder chamber has a straight cylindrical shape, and in the invention according to claim 3, the fluid absorbing portion slides in a reservoir cylinder cylinder having a reservoir cylinder chamber and the reservoir cylinder chamber. And a reservoir cylinder having a reservoir piston that absorbs fluid by raising and lowering the reservoir piston, and the reservoir piston abuts to limit the operation stroke of the reservoir piston and limit the amount of absorption, thereby simultaneously sinking Characterized in that it comprises a blocking body for limiting the amount.

  In the invention according to claim 4, the blocking body is formed such that the contact position with the reservoir piston can be adjusted in the sliding direction of the reservoir piston. In the invention according to claim 5, the blocking body includes the reservoir According to a sixth aspect of the present invention, the blocking body includes a shock absorber provided at the end of the reservoir cylinder.

  In the invention according to claim 7, the two wheels are front wheels, and a pivotal cylinder portion that supports a shaft-like front column rotatably at the front end portion of the main frame and is inclined vertically or downwardly forward. The front column has a handle attached to the upper end, the stationary body extends from the lower end, and forms a steering device with the two-wheel lifting support / suppression means, and in the invention according to claim 8, the stationary body Is a shaft-like body extending downward from the front column, and the movable body is a swinging arm pivotally supported at one end by the stationary body.

  According to the first aspect of the present invention, the two wheels are individually urged downward by the urging means, and the fluid is absorbed into the fluid passage connecting the cylinder chambers of the cylinder devices provided on the two wheels, and the amount of absorption is limited. Because of the fluid absorbing part that is applied, the sudden and drastic sinking that occurs in the two wheels is suppressed when braking suddenly while driving or when it collides with an obstacle on the road surface, and the reaction caused by pushing back is reduced at the same time. To do. As a result, it is possible to prevent the rider from being swung up and down to improve riding comfort, and to maintain a stable steering performance without taking off the steering wheel due to a large shake and to ensure safe driving. Furthermore, with respect to large road surface irregularities such as off-road driving, the two wheels can be prevented from sinking beyond a certain level, and reliable handling can be maintained. However, since the fluid absorption part can move freely up and down without adding resistance to vertical movement within a fixed stroke of the two wheels, a lean posture is formed in response to the rider's left and right weight movement. The As a result, cornering at high speed is stable and comfortable slalom running is also possible. Further, for relatively small irregularities on the road surface, such as riding on a curb block, each two wheels can freely move up and down accordingly, so that stable riding and riding can be performed.

  Since the cylinder chamber of the invention according to claim 2 forms a straight cylinder, the piston and the piston rod repeat linear reciprocating up and down movements, reduce friction, obtain a smooth operation, and are easy to maintain. When configured as in the invention according to Item 3, the operation stroke of the reservoir piston is limited by contact with the blocking body, so that the simultaneous sinking of the two wheels or more is surely prevented.

  When the blocking body is formed so as to be adjustable in the sliding direction of the reservoir piston as in the invention according to claim 4, depending on the traveling purpose such as pottering, off-road, downhill, road racing, road surface condition, traveling speed and other conditions, By adjusting the allowable amount of sinking of the two wheels, it is possible to adjust to the optimum traveling condition. According to claim 5, since the blocking body is made of an elastic body fixed to the inner end of the reservoir cylinder, As a result, the shock that occurs on the two wheels as a reaction is mitigated, and as a result, a sudden change in handling operation can be prevented, and the blocking body of claim 6 comprises a shock absorber provided at the end of the reservoir cylinder. When sinking greatly beyond the bottom limit of the car, its lifting and lowering action is mitigated by the shock absorber, improving riding comfort The handling operation can be stable together.

  In the invention according to claim 7, since the two wheels are the front wheels, and the front column and the two-wheel lifting support / suppression means form a steering device, the front two wheels that are the steering wheels are prevented from sinking beyond a certain level and turned off. Steering wheel operation is possible even for road surface irregularities such as road running, and the movable body of claim 8 is constituted by a swing arm. It can be moved up and down smoothly, and it has a simple structure that reduces weight and reduces maintenance work.

  Hereinafter, the present invention will be described together with illustrated examples based on an embodiment in which the front wheels are two wheels. In the present specification, the term “double wheel” means that the front wheel or the rear wheel is constituted by two wheels that are separated from each other on the left and right. As shown in FIG. 1, a two-wheeled bicycle 1 (hereinafter referred to as a bicycle 1) includes a main frame 4 and a steering device S that is rotatably supported by the front portion.

  The main frame 4 is arranged at the front end and has a cylindrical head tube 4A inclined downward and forward, a top tube 4B extending rearward from the head tube 4A, and an upper tube 4B. A down tube 4D extending diagonally rearward and downward from the head tube 4A on the lower side, a seat tube 4E connecting the rear end of the down tube 4D and the rear end of the top tube 4B, and extending rearward and obliquely downward from the upper end of the seat tube 4E It has a seat stay 4F and a chain stay 4G extending rearward from the lower end of the seat tube 4E, and forms the framework of the bicycle 1. The head tube 4 </ b> A has a cylindrical shape and constitutes a pivotal cylinder portion 3 that supports the steering device S. The head tube 4A of this embodiment is formed to be inclined backward as described above, but may be provided vertically. The saddle 32 is attached to the upper end of the seat tube 4E by fitting the seat pillar 31 so that the height can be adjusted.

  A rear wheel 33 is pivotally supported at the intersection of the rear end of the seat stay 4F and the rear end of the chain stay 4G, and is integrated with the crank 34 at the intersection of the lower end of the seat tube 4E and the lower end of the down tube 4D. A rotating chain ring 35A is pivotally supported. A well-known bicycle drive mechanism is constructed by winding a chain 35B between the chain ring 35A and the sprocket 36 of the rear wheel 33, whereby the bicycle 1 is driven forward. As described above, in the present embodiment, the front two-wheeled three-wheeled vehicle in which the rear wheel 33 is configured as one wheel is illustrated, but the rear wheel 33 may be configured with two wheels or three or more wheels. Furthermore, the front wheel 2 can be a single wheel and the rear wheel 33 can be a two-wheel vehicle.

  The steering device S includes a front column 6 rotatably supported by the pivot cylinder, a handle 5 attached to the upper end of the front column 6, and a two-wheel lifting support attached to the lower end of the front column 6. And suppressing means 7.

  As shown in FIGS. 2 and 3, the front column 6 has a round pipe shape extending in the vertical direction, and an annular convex portion 38 is provided on the outer periphery. A pivotal support portion 39 is formed by an upper portion of the annular convex portion 38. Is done. The pivot portion 39 has an outer diameter that is inserted into the pivot barrel portion 3 of the main frame 4 so as not to rattle and is rotatable, and the outer peripheral surface is finished smoothly. A screw 40 is threaded on the outer periphery of the upper end of the pivotal support 39.

  The pivot 39 is inserted into the pivot cylinder 3 from below. At this time, a lower ball bearing 41D is interposed between the lower end of the pivotal support cylinder portion 3 and the annular convex portion 38. The upper ball press 76 is screwed onto the screw 40 via the upper ball bearing 41U at the upper end of the other pivotal support 39. As a result, the pivotal support 39 is prevented from coming off, and the tightening force of the upper and lower ball bearings 41U and 41D is adjusted. As a result, the front column 6 is pivotally attached to the pivotal support cylinder 3.

  The handle 5 is attached to the top of the front column 6. The handle 5 of this embodiment is exemplified by a handle that includes a hook-shaped handle bar 5A and a handle stem 5B. The handle stem 5B has a vertically long cylindrical vertical axis portion 42 whose lower end surface is inclined, and a front folding portion 43 that is bent forward from the upper end of the vertical axis portion 42 to form an inverted L shape. An intermediate portion of the bar 5A is fixed to the front end of the front folding portion 43. A pulling rod 45 having a hexagonal hole at the upper end and screwed with a screw groove 44 on the outer periphery of the lower portion is inserted into the longitudinal axis portion 42. At the lower portion of the vertical axis portion 42, a pulling mouse 47 having an inclined upper end surface is disposed, and a nut 46 that is screwed into the screw groove 44 of the pulling rod 45 is welded to the lower portion of the pulling mouse 47.

  When the pulling shaft 47 is pulled up by the rotation of the pulling rod 45 using the hexagonal hole, the vertical shaft portion 42 and the pulling shaft 47 of the handle stem 5B are inserted into the pivot support portion 39, and the pulling shaft 47 is pulled. The inclined surfaces facing the usb 47 press each other against the inner peripheral surface of the pivotal support 39, and the handle stem 5 </ b> B is fixed to the pivotal support 39. In this way, the handle 5 is fixed to the front column 7, and as a result, the front column 6 can be rotated by operating the handle bar 5A.

  A two-wheel lifting support / suppression means 7 is attached to the lower end of the front column 6. The two-wheel lifting support / suppression means 7 includes a two-wheel support 11 for supporting the front wheel 2, an urging means 12 for urging the front wheel 2 downward, and two front wheels 2 due to a load from the road surface. It comprises subsidence suppression means 20 for controlling subsidence.

  The two-wheel support 11 includes a stationary body 8 extending downward from the front column 6 and a pair of movable bodies that individually support two front wheels 2 that are attached to the stationary body 8 at one end and that are spaced apart from each other in the axial direction. Nine. The movable bodies 9, 9 are formed so that at least the other end can be moved up and down individually. The front wheel 2 is supported by an elevating part 10 that can move up and down of the movable body 9. The lifting unit 10 refers to a portion of the movable body 9 that moves up and down relatively with respect to the stationary body 8.

  As shown in FIGS. 4 and 5, the stationary body 8 of this embodiment includes an upper extension 8 </ b> U that extends continuously from the lower end of the front column 6 and a downwardly inclined portion 8 </ b> D that tilts downward at the front end. And a curved pipe-like shaft-like body 21 in which the rounded portion 8R that roundly connects the upper extending portion 8U and the downward inclined portion 8D is continuous. A support portion 61 having a horizontally long rectangular parallelepiped shape and having a central hole 18A1 penetrating horizontally is provided at an intermediate portion of the upper extension portion 8U. A cylindrical joint portion 48 is provided at the upper end of the upper extension 8U. By fitting the joint portion 48 to the lower end portion of the front column 6, the shaft-like body 21 and the front column 6 are integrated.

  The movable body 9 of this embodiment has a base end portion arranged in front and pivoted at a pivot point 9P below the lower inclined portion 8D of the stationary body 8, and a free end portion on the rear side swings up and down. It is formed by the arm 22. A pair of the swing arm 22 is disposed on both sides of the stationary body 8 and is pivotally attached to both ends of a horizontal screw shaft 75 that passes through the downwardly inclined portion 8D. In this way, if the swing arms 22 and 22 on both sides are pivotally supported by using both screw shafts 75 through which the stationary body 8 is horizontally passed, the rotational center positions of both swing arms 22 and 22 are not displaced. It is preferable in terms of easy assembly and maintenance. The swing arm 22 of this embodiment is exemplified as a straight square bar, but various shapes such as a circular pipe, a square pipe, an arcuate curved body, and a bent body are used. You can also.

  In addition to the embodiment described above, by providing a protruding portion facing inward at the base end portion of the pair of swing arms 22 and 22, a bearing is provided at the lower portion of the stationary body 8, and the protruding portion is engaged with the bearing. The swing arm 22 can also be pivoted. Alternatively, modifications such as attaching the swing arm 22 via a swing fitting that supports the swing arm 22 are possible. Furthermore, the movable body 9 can also be formed by a slider that can be moved up and down by forming the stationary body 8 in the form of a slide rail extending up and down. Alternatively, the stationary body 8 and the movable body 9 may be formed using a cylinder mechanism including a cylinder cylinder and a piston that slides in the cylinder chamber.

  As shown in FIGS. 2 and 5, one front wheel 2 is pivotally attached to each of the pair of swing arms 22 and 22 at a front wheel pivot attachment point 49 near the tip. As shown in FIG. 9, the two front wheels 2 and 2 are arranged at a distance LW in the width direction of the bicycle 1. The interval LW is, for example, 100 to 500 mm, preferably 150 to 300 mm, and 190 mm in this embodiment. The distance L1 between the arm pivot point 9P and the front wheel pivot point 49 is, for example, 60 to 240 mm, preferably 90 to 180 mm, and 120 mm in this embodiment.

  In this embodiment, a hub shaft 50 projecting outward and cantilevered from the swing arm 22 is inserted into the hub 52 of the front wheel 2, and the front wheel 2 is pivotally attached by screwing a hub nut 52N to the tip thereof. Yes. The bicycle 1 according to this embodiment is equipped with a braking device in which a disk 53 is mounted on the inner side of the hub 52 and a brake pad 54 is provided at the tip of the swing arm 22 to sandwich and brake the disk 53 from both sides. Further, the swing arm 22 provided with the fork members arranged on the left and right sides can be used, and the front wheel 2 can be attached by spanning the hub shaft 50 between the tips of the fork members. When the movable body 9 is configured by pivotally supporting the front wheel 2 at the tip of the swing arm 22 in this way, the front wheel 2 moves up and down smoothly by the vertical swing of the swing arm 22, and the structure is simple. The weight can be reduced and maintenance is easy.

  The urging means 12 is attached between the stationary body 8 and the swing arm 22, biases the front wheel 2 supported by the swing arm 22 downward, and balances with the load received from the road surface via the front wheel 2. At the same time, the increase and decrease of the load during traveling is absorbed to reduce the impact received by the rider. Furthermore, as shown in FIG. 9, the left and right swing arms 22 and 22 are equally biased, and the front wheels 2 and 2 that receive the same amount of load have the same height, which makes it easy to stand upright and travel at a low speed. . The biasing means 12 is formed using an elastic material such as a coil spring, a torsion spring, a leaf spring, an air spring, or rubber.

  As shown in FIGS. 4 and 5, the biasing means 12 of the present embodiment uses a coil spring 55 and constitutes an elastic expansion / contraction member 56 by being extrapolated to the cylinder device 17. As shown in FIG. 6, the cylinder device 17 includes a cylinder cylinder 14 having a flange-shaped receiving portion 57 on the outer periphery, a first mounting portion 58 at the end, and a cylinder chamber 13 inside. The piston rod 16 extends from the piston 15 sliding in the cylinder chamber 13 and has a receiving rod 59 and a second mounting portion 60 at the end. In this embodiment, the piston 15 and the piston rod 16 are formed to have the same diameter, and both are continuously formed into a round bar shape. The first mounting portion 58 is formed with a horizontal mounting hole 58A, and a bottom hole 67 penetrating to the back of the cylinder chamber 13 is formed at the end of the cylinder cylinder 14. The cylinder chamber 13 of the present embodiment is formed in a straight cylinder shape extending straight in the longitudinal direction, and the piston 15 repeats linear reciprocating motion with small motion friction, which is preferable in that smooth reciprocating motion with less vibration can be obtained. However, the cylinder chamber 13 can also be formed in a curved cylindrical shape that continues with a constant curvature. Note that both ends of the coil spring 55 engage with the receiving portion 57 and the receiving rod 59, respectively, and the cylinder cylinder 14 and the piston rod 16 are urged in the extending direction by the spring force.

  A pair of elastic elastic members 56 are bridged between the stationary body 8 and the swing arm 22. That is, the first mounting portion 58 is pivotally supported by screwing the support bolts 62 inserted through the mounting holes 58A into screw holes formed on both sides of the support portion 61 of the stationary body 8, while the second mounting portion 58 is pivotally supported. Are attached to the left and right swing arms 22 at the spring pivot point 51P. As a result, the coil spring 55 pushes down the swing arm 22, and the swing arm 22 is supported at a height at which the load from the road surface and the spring force of the coil spring 55 are balanced. The spring pivot point 51P is provided between the arm pivot point 9P and the front wheel pivot point 49 in this embodiment.

  The distance L2 between the arm pivot point 9P and the spring pivot point 51P is, for example, 30 to 120 mm, preferably 45 to 90 mm, and 60 mm in this embodiment. However, the spring pivot point 51P can be arranged outside the front wheel pivot point 49, and the distance L2 at this time is larger than 120 mm. The free height of the coil spring 55 is, for example, about 60 to 200 mm, preferably 80 to 140 mm, and 100 mm in this embodiment. However, when the spring pivot fulcrum 51P is arranged outside the front wheel pivot attachment point 49, it can be more than 200 mm and about 300 mm. Furthermore, the outer diameter of the coil is, for example, about 12 to 35 mm, preferably 15 to 25 mm, and 21 mm in this embodiment. The spring constant is, for example, about 5.0 to 20.0 N / mm, preferably 7.0 to 15.0 N / mm, when the spring pivot point 51P is intermediate between the arm pivot point 9P and the front wheel pivot point 49. Preferably it is 9.0-11.0 N / mm, and in this embodiment, it is 10.0 N / mm. When the distance L2 is different, a spring constant that is increased or decreased in inverse proportion to the distance L2 is adopted. For example, when the spring pivot point 51P and the front wheel pivot point 49 coincide, 1.5 to 4.0 N / About mm, preferably 2.0 to 3.5 N / mm, more preferably 3.0 N / mm. Using the coil spring 55 in this manner is preferable in that the relationship between the elevation of the front wheel 2 and the urging force against the swing arm 22 can be made linear by the spring constant and the spring reaction force can be arbitrarily set.

  As shown in FIG. 6, the cylinder chambers 13 on both sides are connected by a fluid path 18 that is filled with a fluid such as oil and through which the fluid can move. The fluid passage 18 of this embodiment is formed in the support portion 61 and support bolts 62 screwed to both sides thereof, and a fluid passage 18A that is horizontally continuous, both ends of the fluid passage 18A, and a cylinder chamber. 13 comprises a connection flow path 18B for communicating the upper end portion.

  The supporting bolt 62 that pivotally supports the cylinder cylinder 14 has at least a small diameter opening at the tip of the bolt and extending in the radial direction from the inner side of the side hole 18A2 along the axis and the outer periphery of the side hole 18A2. One branch hole 66 is formed. The fluid main channel 18A is formed by the central hole 18A1 of the support portion 61 and the side hole 18A2 that is concentrically continuous on both sides thereof.

  The support bolt 62 is inserted into the mounting hole 58 </ b> A of the first mounting portion 58 through a cylindrical bush 64 that is oil-sealed by an O-ring 63. The bush 64 is interrupted at a constant length at the central portion, and a gap channel 65 that forms an annular shape along the outer periphery of the support bolt 62 is formed by the interrupted portion. Further, the gap channel 65 is disposed so as to face the bottom hole 67 of the cylinder cylinder 14 and the branch hole 66 of the support bolt 62 and communicate with each other. In the present embodiment, the bottom hole 67, the gap channel 65, and the branch hole 66 form a connection channel 18B that communicates the cylinder chamber 13 and the fluid main channel 18A. Since the bush 64 is oil-sealed with an O-ring 63, the cylinder device 17 is preferably supported so as to be rotatable around the support bolt 62 and oil leakage from the fluid path 18 can be prevented.

  Connected to the fluid passage 18 is a fluid absorbing portion 19 that receives and absorbs fluid flowing from the cylinder chamber 13 into the fluid passage 18 as the front wheel 2 sinks. The fluid absorbing portion 19 of the present embodiment limits a working stroke of the reservoir piston 25 and a reservoir cylinder 26 including a reservoir cylinder cylinder 24 having a reservoir cylinder chamber 23 and a reservoir piston 25 sliding on the reservoir cylinder chamber 23. The thing comprised including the blocking body 27 is illustrated.

  The reservoir cylinder cylinder 24 has a straight cylinder shape extending vertically, and is attached to the lower part of the stationary body 8 by screwing an upper cap nut 68 attached to the upper end part to the lower part of the support part 61. The reservoir cylinder chamber 23 communicates with the fluid path 18 through an inlet / outlet channel 69 provided in the upper cap nut 68, and the lower end portion of the reservoir cylinder cylinder 24 is closed by a lower cap nut 70. Yes.

  The reservoir piston 25 has an upper and lower two-stage O-ring 71 that tightly seals with the inner peripheral surface of the reservoir cylinder chamber 23, and moves up and down by pressure accompanying the flow of fluid from the fluid path 18.

  The blocking body 27 is disposed at the lower part of the reservoir cylinder 26 and prevents the reservoir piston 25 from being further lowered by being pushed by the fluid flowing into the reservoir cylinder chamber 23 and being lowered by a certain stroke. As a result, no more fluid can flow into the reservoir cylinder chamber 23 and the amount of fluid absorbed in the reservoir cylinder chamber 23 is limited.

  The blocking body 27 of this embodiment is formed by an elastic body 28 fixed to the lower end portion of the reservoir cylinder chamber 23. This elastic body 28 is fitted and attached to the upper end of an adjustment bolt 73 with a hexagonal hole screwed into the lower cap nut 70 of the reservoir cylinder cylinder 24. When the adjustment bolt 73 is rotated to move the elastic body 28 up and down, the operating stroke of the reservoir piston 25 increases and decreases, and the maximum absorption amount of the fluid is adjusted. As a result, the sinking amount of the front wheel 2 can be controlled. By adjusting the sinking amount according to the purpose of use, such as pottering, off-road, downhill, road race, rider's age and physical strength, road surface condition, running speed and various other conditions, it is possible to obtain a comfortable and safe driving state preferable. The adjusted position of the elastic body 28 is maintained by tightening the lock nut 74.

  The elastic body 28 is formed using, for example, urethane rubber, silicon rubber, nitrile rubber or other rubber, styrene-based, olefin-based or other thermoplastic elastomer, compression coil spring, disc spring, bamboo shoot spring or other spring. In this embodiment, urethane rubber is used. When such an elastic body 28 is fixed to the end of the reservoir cylinder chamber 23 to form the blocking body 27, the reaction transmitted to the front wheel 2 when the reservoir piston 25 that slides by absorbing the fluid bottoms out is elastic body 28. Therefore, it is preferable in that the vehicle can travel safely without causing the steering operation to be disturbed by an impact. The pair of cylinder tools 17, the fluid path 18 connecting both the cylinder tools 17, and the fluid absorbing portion 19 provided in the fluid path 18 form a sinking suppression means 20.

  Thus, as shown in FIG. 7A, when a load is applied to both the front wheels 2 and the swing arm 22 is lifted against the spring force of the coil spring 55, the piston 15 rises and the inside of the cylinder chamber 13 rises. The fluid pushed out from the fluid passage 18 into the reservoir cylinder chamber 23 flows into the reservoir cylinder chamber 23, whereby the reservoir piston 25 is pushed down. Conversely, when the load on the front wheel 2 is reduced, the piston 15 is pushed down by the coil spring 55, whereby the fluid flows back into the cylinder chamber 13, so that the reservoir piston 25 returns from the reservoir cylinder chamber 23 as shown in FIG. Ascended by fluid. As described above, when the left and right front wheels 2 having a constant height are simultaneously submerged, the fluid pushed out to the fluid passage 18 flows into the reservoir cylinder chamber 23 and is absorbed, and the front wheel 2 is softly supported by the elasticity of the coil spring 55. Therefore, the impact caused by pebbles and small steps on the road surface is alleviated, and an excellent ride comfort is obtained.

  Further, as shown in FIG. 7B, both the front wheels 2 and 2 can be individually depressed against the spring force of the coil spring 55 in the same manner as described above. Therefore, as shown in FIG. 10, when the rider moves his / her body weight to the left and right during turning, the inner front wheel 2 rises to form a stable lean posture, so the front two wheels catch the road surface and turn stably without slipping. it can. As a result, cornering during high-speed traveling is stable and comfortable slalom traveling can be performed freely. Furthermore, as shown in FIG. 11, when the front wheel 2 rides on the step G, the front wheel 2 moves up to maintain the balance of the vehicle body and prevent the vehicle from falling, and the step G continues as shown in FIG. Even when you do this, you can maintain a stable single-wheel riding by moving your weight. Further, as shown in FIG. 13 (A), when it strikes diagonally to the step G, the preceding front wheel 2 rides on while being supported by one front wheel 2 as shown in FIG. Can ride over stably.

  On the other hand, when both the front wheels 2 are subjected to a large load, such as when suddenly braking during driving or when colliding with a large obstacle on the road surface such as a utility pole, as shown in FIG. When the fluid delivered from the cylinder device 17 exceeds the absorption limit of the reservoir cylinder chamber 23, the reservoir piston 25 bottoms out. Therefore, it is possible to prevent the two front wheels from being suddenly and greatly depressed, and to reduce the reaction caused by pushing back the coil spring 55, thereby preventing the rider from swinging up and down. As a result, the ride comfort can be improved and the steering wheel is not taken off by a large shake, so that stable steering performance can be maintained and safe and comfortable travel can be obtained.

  Also, when driving on rough roads, such as off-road driving, and when driving at a high speed on a steep slope while braking by braking, as in downhill, continuously apply impact loads to both front wheels 2 and 2 However, it is necessary to travel while controlling the vehicle body by repeating the instantaneous steering operation. However, as shown in FIG. 8 (A), when the reservoir piston 25 bottoms out, the fluid absorbing portion 19 is supported by the cylinder tool 17 instead of the coil spring 55 for further loads. A rigid steering device S is configured. As a result, it is possible to perform reliable handling that can control the impact load and run off, and lightly travel on off-road and downhill.

  In addition, since the left and right cylinder chambers 13 and 13 communicate with each other via the fluid path 18, the left and right cylinder members 17 and 17 are formed in a seesaw shape even when the reservoir piston 25 is bottomed out as shown in FIG. Mutual expansion and contraction is possible. For this reason, even when the steering wheel is turned off while overriding a large convex part on an off road, or when turning while braking with a sharp curve on a downhill, the front wheel 2 on the inner side of the turn due to the weight movement is also used in the bottomed state of the reservoir piston 25. Lean attitude that sinks can be formed, and it is possible to drive brilliantly by advanced steering technique.

  FIG. 14 illustrates another embodiment. Hereinafter, different contents will be described, and other than that, only the same reference numerals are given to the main components shown in the figure. The blocking body 27 of this embodiment is formed by a shock absorber 29 provided at the end of the reservoir cylinder 26. The shock absorber 29 includes a buffer cylinder cylinder 77 provided inside the lower cap nut 70, a buffer piston 78 sliding in the buffer cylinder cylinder 77, a buffer piston rod 79 extending from the buffer piston 78, and A known mechanism including a buffer spring 80 that biases the buffer piston 78 upward is used.

  A hook-shaped receiving surface 81 is formed at the end of the buffer piston rod 79. As shown in FIG. 15, the reservoir piston 25 that is lowered by the fluid flowing into the server cylinder chamber 13 due to the sinking of the front wheel 2 abuts against and presses the receiving surface 81, but is provided on the buffer piston 78. Since the viscous resistance of the oil passing through the orifice 82 acts as a reaction force, the raising / lowering operation of the front wheels 2 is alleviated to improve the riding comfort and to stabilize the handle operability.

  The above description is an example of the embodiment of the present invention. Therefore, the technical scope of the present invention is not limited to this, and various modifications are included in addition to the above-described embodiment.

It is a front view which illustrates one embodiment of the present invention. It is the principal part enlarged view. It is the principal part expanded sectional view. It is a perspective view which illustrates a two-wheel raising / lowering support and suppression means. It is the front view. FIG. (A) (B) is sectional drawing explaining the different operation | movement condition in the state which has not bottomed out the reservoir cylinder. (A) (B) is sectional drawing explaining the different operation | movement condition in the state which the reservoir cylinder bottomed out. It is a side view which illustrates the upright use state of a twin-wheel bicycle. It is a side view which illustrates the turning state of a twin-wheel bicycle. It is a principal part front view which illustrates the state which gets on the level | step difference of a twin-wheel bicycle. It is a side view which illustrates the state where one wheel of a double-wheeled bicycle was placed on a step and was upright. (A) (B) is a diagram which shows the state which rides on a level | step difference from the diagonal direction. It is principal part sectional drawing which illustrates the other embodiment of this invention. It is principal part sectional drawing explaining the different operation | movement state. It is a perspective view of a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Two-wheel bicycle 2 Front wheel 3 Pivoting cylinder part 4 Main frame 5 Handle 6 Front column 7 Two-wheel raising / lowering support / suppression means 8 Stationary body 9 Movable body 10 Lifting part 11 Two-wheel support 12 Energizing means 13 Cylinder chamber 14 Cylinder cylinder 15 Piston Reference Signs List 16 piston rod 17 cylinder tool 18 fluid path 19 fluid absorption part 20 sinking suppression means 21 shaft-like body 22 swing arm 23 reservoir cylinder chamber 24 reservoir cylinder cylinder 25 reservoir piston 26 reservoir cylinder 27 blocking body 28 elastic body 29 shock absorber S Steering device

Claims (8)

A double-wheeled bicycle comprising at least one of a front wheel or a rear wheel and two wheels separated on the left and right,
The main frame that stretches back and forth to form the entire framework,
A two-wheel lifting support / suppression means for supporting the two wheels so as to move up and down at an interval in the axial direction and suppressing simultaneous sinking of the two wheels;
The two-wheel lifting support / suppression means is:
The two wheels are axially connected to the other end of a stationary body, and a lifting part composed of a pair of movable bodies that engage with the stationary body and at least the other end moves up and down independently of the stationary body. A wheel support that supports the space apart;
A biasing means for individually biasing the two wheels downwardly by being mounted between the stationary body and the movable body;
A cylinder tool comprising a cylinder cylinder having a cylinder chamber and a piston rod extending from a piston sliding in the cylinder chamber is individually provided on the two wheels, and the cylinder cylinder is attached to the stationary body and the piston rod is attached to the movable body. In addition, the fluid path connecting both the cylinder chambers includes a subsidence suppression means provided with a fluid absorption part that absorbs fluid and restricts the amount of absorption when the two wheels sink simultaneously. Twin-wheel bicycle.   The twin-wheel bicycle according to claim 1, wherein the cylinder chamber has a straight cylindrical shape.   The fluid absorption portion has a reservoir cylinder having a reservoir cylinder cylinder having a reservoir cylinder chamber and a reservoir piston sliding in the reservoir cylinder chamber, and absorbs fluid by raising and lowering the reservoir piston, and the reservoir piston The two-wheeled bicycle according to claim 1 or 2, further comprising a blocking member that restricts a simultaneous sinking amount by abutting and limiting an operation stroke of the reservoir piston and limiting an absorption amount.   The dual-wheel bicycle according to claim 3, wherein the blocking body is formed such that a contact position with the reservoir piston is adjustable in a sliding direction of the reservoir piston.   The twin-wheel bicycle according to claim 3 or 4, wherein the blocking body is made of an elastic body fixed to an inner end portion of a reservoir cylinder.   The twin-wheel bicycle according to claim 3 or 4, wherein the blocking body comprises a shock absorber provided at an end of a reservoir cylinder. The two wheels are front wheels,
The front end portion of the main frame is provided with a pivotal cylinder portion that rotatably supports a shaft-like front column and that is inclined vertically or downward.
The two-wheel according to any one of claims 1 to 6, wherein a handle is attached to an upper end of the front column, the stationary body extends from the lower end, and the two-wheel lifting support / suppression means forms a steering device. bicycle.   8. The twin-wheel bicycle according to claim 7, wherein the stationary body is a shaft-like body extending downward from the front column, and the movable body is a swinging arm pivotally supported at one end by the stationary body. .

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