JP5572377B2 - Bicycle with posture maintenance device - Google Patents

Description

  The present invention relates to a bicycle provided with a posture maintaining device that stabilizes the posture of a driver regardless of the ground contact height of left and right wheels.

There is a bicycle in which a front wheel or a rear wheel is composed of a pair of left and right wheels. There is a bicycle in which the pair of left and right wheels can independently rotate in the vertical direction. In this bicycle, the left and right wheels are respectively biased downward by springs. On a slope inclined in the left-right direction, the wheel rotates in accordance with the slope of the slope. This bicycle can run without tilting on a slope inclined left and right. On a road with large unevenness, the left and right wheels rotate in accordance with the unevenness. This bicycle can travel stably on a road with large unevenness. In cornering, the left and right wheels can be grounded with the bicycle body tilted. This bicycle can run in a stable manner.
JP 2006-56493 A

  In a bicycle in which the biasing force of the spring that biases the wheel downward is small, the vehicle body shakes in the vertical direction is large. Sudden braking causes the bicycle body to sink significantly. The bicycle is greatly shaken up and down. On the other hand, in a bicycle with a large spring biasing force, the following ability of the wheel to the road surface is impaired. The reaction force of the spring increases, making it difficult to operate the handle.

  It is conceivable that this bicycle is provided with an elevating mechanism in which one wheel moves in the opposite direction to one wheel when one wheel moves in any direction in the vertical direction. Bicycles provided with this lifting mechanism can reduce the vertical movement of the vehicle body. In this bicycle, the biasing force of the spring can be made relatively small. Thereby, the followability to the road surface of the left and right wheels is not impaired.

  In this bicycle, the left and right wheels are restricted from rotating in the same direction in the vertical direction. When the left and right wheels are rotated in the same direction in the vertical direction, the driver receives a sudden reaction force from the vehicle body. There is a risk that the driver may be thrown forward in a bicycle that is braked suddenly.

  An object of the present invention is to provide a bicycle including a posture maintaining device that is excellent in running stability regardless of the ground contact height of the left and right wheels.

  A bicycle according to the present invention includes a main frame, a pair of left and right wheels, and a posture maintaining device. This posture maintaining apparatus includes an elevating mechanism, a pair of left and right support mechanisms, and a first elastic body. Each support mechanism includes a second elastic body. This support mechanism supports the wheel rotatably. The support mechanism supports the wheel so as to be movable in the vertical direction with respect to the main frame. The second elastic body biases the wheel downward with respect to the main frame. By this lifting mechanism, when one wheel moves in any direction in the vertical direction, the other wheel moves in the opposite direction to the one wheel. The lifting mechanism is supported by the main frame so as to be movable in the vertical direction. The lifting mechanism is urged downward with respect to the main frame by the first elastic body.

  Preferably, in the bicycle according to the present invention, the spring constant of the first elastic body is larger than the spring constant of the second elastic body.

  Preferably, the bicycle support mechanism according to the present invention includes an arm. This arm is rotatably supported by the main frame. The arm is biased by the second elastic body so as to rotate downward with respect to the main frame. This arm rotatably supports the wheel. The lifting mechanism is engaged with the arm.

  Preferably, the bicycle lifting mechanism according to the present invention includes a support frame, a first roller, a second roller, and a belt. The support frame rotatably supports the first roller and the second roller. The first roller is located above the support frame. The second roller is located below the support frame. A belt is stretched between the first roller and the second roller. One arm is engaged with one portion of the belt between the first roller and the second roller. The other arm is engaged with the other part of the belt between the first roller and the second roller. The support frame is biased downward with respect to the main frame by the first elastic body.

  The bicycle according to the present invention is excellent in running stability even if there is a height difference between the left and right wheels. This bicycle has excellent running stability in both straight running and cornering running. This bicycle has excellent stability even during sudden braking.

FIG. 1 is a front view of a bicycle according to an embodiment of the present invention. FIG. 2 is a view of the front wheel, posture maintaining device, and part of the steering shaft of the bicycle shown in FIG. FIG. 3 is a conceptual diagram showing a use state of the front wheel and posture maintaining device of the bicycle of FIG. FIG. 4 is an enlarged view showing a use state of the bicycle posture maintaining apparatus of FIG. FIG. 5 is a conceptual diagram showing a use state of the front wheel and posture maintaining device of the bicycle of FIG.

  Hereinafter, the present invention will be described in detail based on preferred embodiments with appropriate reference to the drawings.

  FIG. 1 is a front view of a bicycle 2 according to an embodiment of the present invention. The rightward direction in FIG. 1 is the forward direction of the bicycle 2. The left direction in FIG. 1 is the rear direction of the bicycle 2. The bicycle 2 includes a main frame 4, a pair of left and right front wheels 6, a rear wheel 8, a posture maintaining device 10, and a drive device 12.

  The main frame 4 includes a main body 13, a steering device 14, and a saddle 16. The saddle 16 is located above the main frame 4. The steering device 14 includes a handle 18 and a steering shaft 20. The handle 18 is fixed to the steering shaft 20. The center of the handle 18 is fixed to the upper end of the steering shaft 20. The steering shaft 20 is located in front of the main frame 4. The steering shaft 20 is supported by the main body 13 of the main frame 4. The steering shaft 20 can rotate with respect to the main body 13. The steering shaft 20 can rotate about its axis as a rotation axis.

  FIG. 2 is a view of the front wheel 6, the posture maintaining device 10, and a part of the steering shaft 20 of the bicycle 2 of FIG. A shaft 22 extends in the left-right direction from below the steering shaft 20 supported by the main body 13. A further lower portion of the steering shaft 20 is bent rearward substantially at a right angle. A shaft 24 extends in the left-right direction at a distal end that bends and extends rearward. A hole 26 is formed between the tip extending rearward and the bent portion. The hole 26 penetrates in the vertical direction.

  The posture maintaining apparatus 10 includes an elevating mechanism 28, a coil spring 29 as a first elastic body, and a pair of support mechanisms 30. The elevating mechanism 28 includes a support frame 32, a sprocket 34 as a first roller, a sprocket 36 as a second roller, a chain 38 as a belt, a pin 40, a washer 42, and an adjustment nut 44. The support frame 32 has a bar shape extending in the vertical direction. A male screw 48 is formed in the lower portion of the support frame 32.

  A sprocket 34 is supported on the upper end of the support frame 32. The sprocket 34 can rotate with respect to the support frame 32. A sprocket 36 is supported at the lower end of the support frame 32. The sprocket 36 can rotate with respect to the support frame 32. A chain 38 is spanned between the sprocket 34 and the sprocket 36. The upper part of the chain 38 meshes with the sprocket 34. The lower part of the chain 38 meshes with the sprocket 36. One portion of the chain 38 extending in the vertical direction between the sprocket 34 and the sprocket 36 is located on the right side of the steering shaft 20. The other part of the chain 38 extending in the vertical direction is located on the left side of the steering shaft 20. A right pin 40 is connected to one part of the chain 38. A left pin 40 is connected to the other part of the chain 38.

  The support frame 32 is passed through the hole 26 of the steering shaft 20. The support frame 32 is supported in the hole 26 via a linear bearing (not shown). The support frame 32 can move up and down with respect to the steering shaft 20. An adjustment nut 44 is attached to the male screw 48. The adjusting nut 44 is composed of two nuts. The adjustment nut 44 can be positioned and fixed in the vertical direction of the support frame 32. The washer 42 is located facing the lower surface of the steering shaft 20. The washer 42 is passed through the support frame 32. The coil spring 29 is located between the washer 42 and the adjustment nut 44. The coil spring 29 is passed through the support frame 32. The coil spring 29 urges the support frame 32 downward with respect to the steering shaft 20.

  One support mechanism 30 is located on the right side of the main frame 4. The other support mechanism 30 is located on the left side of the main frame 4. The support mechanism 30 includes an arm 50 and an extender 52, respectively. One end of the arm 50 is attached to the shaft 24 of the steering shaft 20. The arm 50 can rotate about the shaft 24 as a rotation axis. A front wheel 6 is pivotally attached to the other end of the arm 50. The front wheel 6 can rotate with respect to the arm 50 about the left-right direction as a rotation axis.

  A long hole 54 is formed in the arm 50. The long hole 54 penetrates in the left-right direction. The long hole 54 is formed along the longitudinal direction of the arm 50. The pin 40 is slidably engaged with the long hole 54. A stay 56 is formed between both ends of the arm 50. The stay 56 is formed above the arm 50.

  The extender 52 includes a body 58 that can expand and contract, a coil spring 60 as a second elastic body, an adjustment nut 62, and a washer 64. A male screw 66 is formed on the outer periphery above the main body 58. The adjusting nut 62 includes two nuts. The adjustment nut 62 is attached to the male screw 66. The adjusting nut 62 can be positioned and fixed in the axial direction of the main body 58. A coil spring 60 and a washer 64 are passed through the main body 58. The coil spring 60 is located between the adjustment nut 62 and the washer 64. The coil spring 60 biases the washer 64 away from the adjustment nut 62. The main body 58 is biased by the coil spring 60 in the extending direction.

  The upper end of the extender 52 is attached to the shaft 22 of the steering shaft 20. The lower end of the extender 52 is pivotally attached to the stay 56 of the arm 50. The arm 50 is urged by a telescopic device 52 in a direction of rotating downward. Thereby, the front wheel 6 is biased downward.

  The rear wheel 8 is attached to the main frame 4. The rear wheel 8 can rotate with respect to the main frame 4. The rear wheel 8 can rotate about the rotation axis in the left-right direction.

  As shown in FIG. 1, the drive device 12 includes a pair of left and right cranks 68, a drive gear 70, a drive chain 74, and a driven gear 76. The pair of left and right cranks 68 are attached to the main frame 4. The crank 68 is located on the left and right side surfaces of the main frame 4. The crank 68 can rotate with respect to the main frame 4. The drive gear 70 is attached to the main frame 4. The drive gear 70 can rotate with respect to the main frame 4. The rotating shaft of the crank 68 and the rotating shaft of the drive gear 70 are coaxial. The rotation axis has an axis in the left-right direction. The driven gear 76 is attached to the rear of the main frame 4. The driven gear 76 can rotate with respect to the main frame 4. The rear wheel 8 and the driven gear 76 are integrated. The rotation axis of the rear wheel 8 and the driven gear 76 is coaxial. A drive chain 74 is bridged between the drive gear 70 and the driven gear 76.

  The driver steps on the pedal of the crank 68 of the bicycle 2 in FIG. The crank 68 rotates. The drive gear 70 is rotated by the rotation of the crank 68. The rotation of the drive gear 70 is transmitted to the drive chain 74. The drive chain 74 rotates the driven gear 76. As the driven gear 76 rotates, the rear wheel 8 rotates. The bicycle 2 travels by the rotation of the front wheel 6.

  FIG. 3 is a conceptual diagram showing a use state of the front wheel 6 and the posture maintaining device 10 of the bicycle 2 of FIG. FIG. 3A shows a use state in which the left and right front wheels 6 are grounded at the same height. FIG. 3B shows a use state in which the right front wheel 6 is grounded at a high position. When the right front wheel 6 of the bicycle 2 rides on the convex portion, the right front wheel 6 is pushed upward. The right arm 50 rotates. By rotating the arm 50, the long hole 54 moves upward. The pin 40 engaged with the long hole 54 moves upward. The chain 38 to which the pin 40 is connected is fed counterclockwise.

  When the chain 38 is fed counterclockwise, the left pin 40 moves downward. The long hole 54 moves downward by the pin 40. As a result, the left arm 50 rotates downward. The left front wheel 6 is lowered with respect to the main frame 4. In this way, the use state shown in FIG. 3A changes to the use state shown in FIG.

  FIG. 4 is an enlarged view showing a use state of the posture maintenance device 10 of the bicycle 2 of FIG. FIG. 4A shows the posture maintaining device 10 for the bicycle 2 that contacts the right front wheel 6 at a high position. FIG. 4B shows a posture maintaining device 10 for the bicycle 2 that is in contact with the right front wheel 6 at a low position.

  The expander 52 expands and contracts according to the vertical rotation of the arm 50. The coil spring 60 of the extender 52 urges the arm 50 downward. By urging the arm 50 downward, the front wheel 6 is grounded to the road surface. As shown in FIG. 4A, when the right front wheel 6 moves upward, the arm 50 rotates upward. The coil spring 60 is contracted. The stretcher 52 is shrunk. Further, as shown in FIG. 4B, when the right front wheel 6 moves downward, the arm 50 rotates downward.

  The front wheel 6 is grounded to the road surface by the biasing force of the coil spring 60 via the arm 50. The front wheel 6 can move up and down corresponding to the unevenness of the road surface. Due to the biasing force of the coil spring 60, the rotation of the front wheel 6 and the arm 50 becomes smoother. In the bicycle 2, the initial length of the coil spring 60 can be changed by the adjustment nut 62. Thereby, the strength of the urging force of the coil spring 60 can be adjusted according to the preference of the driver. The second elastic body using the coil spring 60 only needs to be able to expand and contract by urging the arm downward. What is necessary is just to provide this function, and a 2nd elastic body is not restricted to a coil spring.

  As shown in FIG. 4 (b), the right front wheel 6 falls downward with respect to the main frame 4 in the recess. As a result, the chain 38 is sent. As a result, the left front wheel 6 moves upward with respect to the main frame 4. The right front wheel 6 is grounded at a position lower than the left front wheel 6. In the bicycle 2, when a difference in height occurs between the left and right front wheels 6, one wheel moves in either the vertical direction. The other wheel moves in the opposite direction to the one wheel.

  In the bicycle 2, the chain 38 is sent along the vertical direction of the steering shaft 20. The left and right front wheels 6 are rotated in the vertical direction of the steering shaft 20 by the chain 38. The absolute values of the movement distances of the left and right front wheels 6 in the vertical direction are equal.

  On the slope inclined right and left, the left and right front wheels 6 move up and down in accordance with the slope. The main frame 4 does not tilt on this slope. In this bicycle 2, the posture of the driver while traveling is stable. Even if one front wheel 6 rides on the convex portion of the road surface, the bicycle 2 does not tilt. Even if one front wheel 6 is taken in the recess of the road surface, the bicycle 2 does not tilt. In the bicycle 2, the vertical direction of the main frame 4 can coincide with the vertical direction even if there is a height difference between the left and right ground planes. With this posture maintenance device 10, the bicycle 2 can maintain a stable posture. In this bicycle 2, the posture of the driver while traveling is stable. In this bicycle 2, the handle 18 is prevented from being taken. This bicycle 2 is excellent in handling stability.

  The double-headed arrows W in FIGS. 3A and 3B are the distances between the left and right front wheels 6 in the left-right direction. In this bicycle 2, the interval W is constant even if there is a height difference between the left and right front wheels 6. In the bicycle 2, even if the front wheel 6 moves in the vertical direction, the force for moving the front wheel 6 in the axial direction does not act. The traveling of the bicycle 2 is stable. The front wheel 6 of the bicycle 2 has a reduced frictional force in the direction of the rotation axis. In the bicycle 2, a chain 38 is bridged between the sprocket 34 and the sprocket 36. Thereby, this space | interval W can be narrowed.

  In the bicycle 2, the pair of front wheels 6 moves in the vertical direction from a state where there is no height difference between the left and right rear wheels 8 to a state where a height difference occurs between the left and right rear wheels 8. In this bicycle 2, the vertical movement distance of one front wheel 6 is equal to the absolute value of the vertical movement distance of the other front wheel 6. Thereby, it is suppressed that the main frame 4 and the attitude | position support apparatus 12 earth | ground. The amount of vertical movement of the main frame 4 is also reduced. This bicycle 2 is excellent in running stability.

  The driver opens the handle 18. As the handle 18 rotates, the steering shaft 20 rotates. As the steering shaft 20 rotates, the traveling direction of the front wheels 6 is changed. Thereby, the traveling direction of the bicycle 2 is changed.

  In cornering traveling of the bicycle 2, the main frame 4 is tilted with the driver putting weight on the turn direction. The front wheel 6 inside the cornering traveling is turned upward. The outer front wheel 6 is rotated downward. The bicycle 2 can be run at an angle. This bicycle 2 is capable of cornering traveling in a stable posture.

  FIG. 5 is a conceptual diagram showing a use state of the front wheel 6 and the posture maintaining apparatus 10 of the bicycle 2 of FIG. The suddenly braked bicycle 2 tends to sink greatly forward. The bicycle 2 includes a coil spring 29. In this bicycle 2, the steering shaft 20 sinks downward. The coil spring 29 is contracted. Thereby, even if this bicycle 2 is rotated upward simultaneously by the pair of left and right front wheels 6, the bicycle 2 is not easily shaken. Similarly, when the pair of right and left wheels ride on the convex surface of the road surface, the coil spring 29 suppresses the shake of the bicycle 2 to be small. Similarly, when the pair of front wheels 6 falls on the concave surface of the road surface, the swing of the bicycle 2 is suppressed to be small. In this bicycle 2, the initial length of the coil spring 29 can be changed by the adjustment nut 44. Thereby, the strength of the urging force of the coil spring 29 can be adjusted according to the preference of the driver.

  In the bicycle 2, the coil spring 60 biases the arm 50 downward. Thereby, the front wheel 6 is made to follow the unevenness | corrugation of a road surface. On the other hand, the coil spring 60 applies a reaction force to the front wheel 6 via the arm 50. The spring constant of the coil spring 60 is set so that the front wheel 6 follows the unevenness of the road surface and applies a reaction force to the front wheel 6.

  On the other hand, the left and right front wheels 6 are rotated in the opposite directions in the vertical direction by the lifting mechanism 28. Thereby, the shake of the bicycle 2 in the vertical direction is suppressed.

  The elevating mechanism 28 is urged downward by a coil spring 29. The spring constant of the coil spring 29 is preferably larger than the spring constant of the coil spring 60. Thereby, the coil spring 29 greatly contributes to the relaxation of the sinking amount of the bicycle 2. The sudden braking of the bicycle 2 is suppressed.

  Here, the bicycle 2 provided with a pair of front wheels 6 has been described as an example. A bicycle including a pair of rear wheels 8 may be used. A pair of rear wheels are supported by the posture support device. This posture support device is supported by the main frame via a coil spring as a first elastic body. Thus, even when the left and right rear wheels ride on the convex surface of the road surface simultaneously, the swing of the bicycle 2 is reduced by the first elastic body. Similarly, when the pair of front wheels 6 falls on the concave surface of the road surface, the vibration of the bicycle 2 is reduced. The riding comfort is improved particularly in a bicycle equipped with an auxiliary seat on which the passenger is placed behind the saddle.

  A shock absorber may be used for the main body 58 of the expander 52. Thereby, the expansion / contraction speed becomes slow and the ride comfort can be improved. From the same viewpoint, a shock absorber may be provided between the steering shaft 20 and the support frame 32.

  In the bicycle according to the present invention, the driver's posture is stabilized regardless of the ground contact height of the left and right wheels. This bicycle is excellent in running stability in both straight running and cornering running.

  The bicycle according to the present invention includes a wheelchair.

2 ... bicycle 4 ... main frame 6 ... front wheel 8 ... rear wheel 10 ... posture maintenance device 12 ... drive device 13 ... main body 14 ... steering device 16 ... Saddle 18 ... handle 20 ... steering shaft 22 ... shaft 24 ... shaft 26 ... hole 28 ... lifting mechanism 29 ... coil spring 30 ... support mechanism 32 ... support Frame 34, 36 ... Sprocket 38 ... Chain 40 ... Pin 42 ... Washer 44 ... Adjustment nut 48 ... Male screw 50 ... Arm 52 ... Extender 54 ... Long Hole 56 ... Stay 58 ... Body 60 ... Coil spring 62 ... Adjusting nut 64 ... Washer 66 ... Male screw 68 ... Crank 70 ... Drive gear 74 ... Drive chain 76 ... driven gear

Claims (4)

A main frame, a pair of left and right wheels, and a posture maintaining device;
This posture maintaining device includes a lifting mechanism, a pair of left and right support mechanisms, and a first elastic body,
Each support mechanism has a second elastic body,
This support mechanism supports the wheel rotatably,
This support mechanism supports the wheel to be movable in the vertical direction with respect to the main frame,
This second elastic body urges the wheel downward relative to the main frame,
When one wheel moves in any direction in the vertical direction by this lifting mechanism, the other wheel moves in the opposite direction to one wheel,
The lifting mechanism is supported movably in the vertical direction against the main frame,
A bicycle in which the lifting mechanism is biased downward with respect to the main frame by the first elastic body.   The bicycle according to claim 1, wherein a spring constant of the first elastic body is larger than a spring constant of the second elastic body. The support mechanism includes an arm,
This arm is rotatably supported by the main frame,
This arm is biased by the second elastic body in a direction of rotating downward with respect to the main frame,
This arm supports the wheel for rotation,
The bicycle according to claim 1 or 2, wherein the lifting mechanism is engaged with an arm. The lifting mechanism includes a support frame, a first roller, a second roller, and a belt;
The support frame rotatably supports the first roller and the second roller,
The first roller is located above the support frame;
The second roller is located below the support frame,
A belt is stretched over the first roller and the second roller,
One arm is engaged with one part of the belt between the first roller and the second roller,
The other arm is engaged with the other part of the belt between the first roller and the second roller;
The bicycle according to any one of claims 1 to 3, wherein the support frame is urged downward with respect to the main frame by the first elastic body.

Images