JPH037554B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to two-wheeled vehicles such as bicycles and motorcycles that can drive both front and rear wheels.

(Prior art) Conventional two-wheeled vehicles are rear-wheel drive, and a chain transmission type is often used as a transmission device, and a chain change type for a multi-stage sprocket has been put into practical use as a transmission means. There is.

Further, as transmission means other than those described above, there are those disclosed, for example, in Japanese Patent Publication No. 34-1722 and Japanese Patent Application Laid-open No. 54-93754, but both of these are rear wheel drive systems using a chain.

(Problems to be Solved by the Invention) However, in recent years, there has been a demand for cycles suitable for running on rough terrain as sports vehicles such as cross-country cycles and mountain cycles. The advantages of front-wheel drive or all-wheel drive systems that simultaneously drive the front and rear wheels when traveling on rough terrain have been known for a long time, but as mentioned above, conventional motorcycles mainly drive only the rear wheels using a chain. However, there is a problem in that it is very difficult to drive the front wheel of a two-wheeled vehicle, which constantly changes direction along with the steering wheel, using a chain transmission system.

The present invention was made to solve this problem and further improve the performance of motorcycles, and is an all-wheel drive motorcycle that can drive both the front and rear wheels and is suitable as a sports vehicle such as a cross-country cycle or a mountain cycle. Another object of the present invention is to provide a two-wheeled vehicle in which drive wheels can be freely selected and driven, allowing either the front or rear wheels to be freely selected and driven as necessary.

(Means for solving the problem) In order to achieve the above-mentioned object, in the present invention,
An inner eccentric cam is fixed to the central shaft, and an outer eccentric cam is rotatably fitted to the outer periphery of the inner eccentric cam, integrally forming an internal gear wheel centered on the central shaft, An internal gear identical to this internal gear is arranged concentrically with an internal gear integral with the inner eccentric cam so as to rotate together with the outer eccentric cam, and rotatably with each other. is rotatably provided, and gears that mesh with the center gear and the one internal gear are pivotally supported on a fixed shaft, and the same gears are connected to the center gear and the other internal gear. The eccentric cam is provided on the free end of an arm that is rotatably supported on the central shaft, and by rotating this arm, the eccentricity of the eccentric cam is controlled steplessly. A variable displacement fluid pump utilizing the same is installed at the input part of the transmission system of a two-wheeled vehicle, fixed displacement fluid motors are provided for each of the front and rear wheels, and the fluid pump and the fluid motor are connected by an oil path. A switching valve is installed in the front and rear wheels to enable selection of front and rear wheel drive.

(Function) As described above, in the present invention, since both the front and rear wheels can be driven, it can be used as a sports vehicle such as a cross-country cycle or a mountain cycle suitable for riding on rough terrain, compared to a conventional rear-wheel drive two-wheel vehicle. It is possible to demonstrate excellent performance that cannot be obtained previously.

Furthermore, in the present invention, since either the front or rear wheels can be freely selected and driven as required, the two-wheeled vehicle can be driven using a drive system suitable for all situations.

Furthermore, since the present invention transmits power via fluid (for example, pressure oil), the sprocket and chain required by conventional two-wheeled vehicles are completely unnecessary.

In addition, by steplessly changing the discharge volume of the variable displacement fluid pump, stepless speed change can be easily achieved, noise and pulsation can be reduced, and a wide range of gear ratios can be easily obtained. Can be done.

In addition, in the fluid transmission two-wheeled vehicle of the present invention, since fluctuations in the driving force of the vehicle immediately appear as changes in the pressure of the transmission fluid, the discharge amount of the variable displacement fluid pump is controlled in accordance with this pressure change. Ba,
Automatic gear shifting can also be easily achieved.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. In the diagram, 1 is the front wheel of the bicycle, 2 is the front fork, 3 is the handle, 4 is the head pipe, 5 is the main pipe, 6 is the vertical pipe, 7 (see Figure 3) is the hanger pipe, 8 is the crankshaft, and 9 is the crank arm. , 10 is the crank pedal, 11 is the front wheel hub axle,
12 is a backhawk, 13 is a rear wheel, and 14 is a rear wheel hub axle.

In this embodiment, a disk-shaped variable displacement hydraulic pump A is attached to the input part of the bicycle's transmission system around the crankshaft 8, and a constant displacement hydraulic motor B is attached to the front wheel hub shaft 11 and the rear wheel hub. The hydraulic pump A and the rear wheel drive hydraulic motor B are connected to each other by a connecting member 15 which is attached to the output part of the bicycle's transmission system via a shaft 14 and has a discharge side oil passage and a suction side oil passage therein. At the same time, a swivel joint (a rotatable joint for oil passages) 80 is provided in the head pipe 4, and the discharge side is connected between the hydraulic pump A, which is installed around the crankshaft 8, and the hydraulic motor B, which is attached to the front wheel hub axle 11. The oil passage 81 and the suction side oil passage 82 are connected via a swivel joint 80 . Note that the oil passages 81 and 82 may be provided in the main pipe 5 and the front fork 2, respectively.

Furthermore, the connecting member 15 can also serve as a chain stay. It is convenient to use the inside of the vertical pipe 6 as an oil tank.

FIGS. 2 to 6 show preferred embodiments of the variable displacement hydraulic pump A, the eccentric cam eccentric control device C attached thereto, and the automatic transmission actuating device D cooperating therewith. be.

That is, 16 is a disk-shaped pump case, the outer center hole 17 fits into the boss portion 9a of the crank arm 9 as shown in FIG. 3, and the inner center hole 18 allows rotation of an outer eccentric cam to be described later. It has a suitable diameter. And inside this pump case 16,
A plurality of sets (eight sets in this embodiment) of plunger type suction/exhaust devices are arranged radially around the crankshaft 8, which is the central axis. That is, 19 is the cylinder hole,
20 is a plunger, 21 is a cam follower rotatably supported at the inner end of each plunger 20, 22
is a coil spring that always presses the plunger 20 inward. Reference numeral 23 denotes a suction side oil passage provided in a ring shape on the outer periphery of the pump case 16, and this oil passage 23 communicates with an oil tank 25 provided in the vertical pipe 6 through a pipe 24, as shown in FIG. I have let you. Reference numeral 26 denotes a discharge side oil passage arranged in parallel with the suction side oil passage 23 on the outer periphery of the pump case 16, and these oil passages 23 and 26 communicate with each cylinder hole 19 through check valves 27 and 28, respectively. It has been done.
27 is a check valve on the suction side, and 28 is a check valve on the discharge side, each of which is constructed of balls 27a, 28a and coil springs 27b, 28b. Further, the oil passage 29 shown in FIG. 2 is for returning leaked oil to the suction side oil passage 23.

Reference numeral 30 denotes an inner eccentric cam fixed to the crankshaft 8 with a key 31, and this inner eccentric cam 30 is integrally formed with an inner internal gear 33 via a disc portion 32 located outside the pump case 16. be. 3
Reference numeral 4 denotes an outer eccentric cam that is rotatably fitted to the inner eccentric cam 30, and this outer eccentric cam 34 has a projection 35 located between the outer surface of the pump case 16 and the disk portion 32 (see FIG. 4). It is formed integrally with
An outer internal gear wheel 38 is formed integrally with a disc portion 37 having a notched groove 36 which is fitted into the projecting piece 35 in a swingable and slidable manner. It has the same number of teeth and the same pitch diameter as the gear wheel 33, and is fitted concentrically to the inner gear wheel 33 so as to be rotatable.

In the embodiment shown in FIG. 4, the circular end of the projecting piece 35 only makes line contact with the cutout groove 36, so in order to increase this contact area, as shown in FIG.
A sliding piece 39 may be inserted between the protruding piece 35 and the notch groove 36.

Further, 40 is a central gear rotatably fitted to the crankshaft 8, 41 is a fixed gear that meshes with the central gear 40 and the one internal gear 38, and this gear 41 is connected to the hanger pipe 7. It is rotatably supported by a protruding bracket 42. 43 is the center gear 40 and the other internal gear 3
3, and is rotatably supported by the free end of an arm 44 whose base is rotatably fitted to the crankshaft 8. A gear 45 is formed at the base of this arm 44, and a sector gear 46 that meshes with this gear 45 is formed integrally with an eccentric operating lever 47, and its intermediate portion is connected to the shaft 4.
It is fixed to the frame via 7a. These gear devices constitute an eccentric control device C for an eccentric cam.

Further, as shown in FIG. 6, the eccentric operating lever 47 is connected to the tip of a piston rod 50 that is connected to a piston 49 in a hydraulic cylinder 48 that constitutes the automatic transmission actuating device D, and the cylinder 48 is connected to a bicycle frame 51. It is pivoted so that it can swing freely. 52 is a coil spring for returning the piston 49 inserted into the cylinder 48, and the pressure chamber 53 on the opposite side of this spring 52 and the discharge side oil passage 26 of the hydraulic pump A are shown by two-dot chain lines in FIG. As shown in FIG. 3, the empty chamber 55 on the side of the coil spring 52 is communicated with the oil tank 25 by a flexible hose 56 as shown by the two-dot chain line in FIG. 3 to drain the leaked oil. It is arranged to be returned to the oil tank 25.

7 and 8 show an embodiment of a constant displacement hydraulic motor B fitted to the rear wheel hub shaft 14 of a bicycle to drive the rear wheel hub 57. However, the installation method is the same.
This constant displacement hydraulic motor B is a gear type hydraulic motor consisting of a pair of gears. This gear-type hydraulic motor has one gear 58 having a larger diameter than the other gear 59, and a shaft cylinder 61 formed integrally with a gear case 60 in the center of the large-diameter gear 58. is fitted onto the hub shaft or 11 of the driving wheel and fixed with a nut 62, and an output shaft 63 of a large diameter gear 58 is connected to the hub 57 of the driving wheel via a one-way clutch 64. 65 is a gear case body that is connected to the gear case 60 by bolts 66, 67 is a pressure side recess provided in the gear case body 65, 68 is an oil passage on the pressure side thereof, 69 is a recess on the oil drain side, and 70 is a return side. It is an oil road.

Further, 71 shown in FIG. 8 is a needle roller inserted between the shaft cylinder 61 and the inner peripheral surface of the gear 58, and 72 is a needle roller inserted into the shaft cylinder 61 and the inner peripheral surface of the gear 58.
1, an annular groove for an oil reservoir carved on the circumferential surface of 1, 73 a seal ring, 74 a ball bearing, 75 a needle roller inserted between the output shaft 63 and the shaft hole of the gear case body 65, and 76 the shaft hole. An annular groove 77 for an oil reservoir carved on the inner circumferential surface of the output shaft 73 is a seal ring fitted to the output shaft 73.

Since leaked oil accumulates in the annular grooves 72 and 76, the oil in the annular groove 72 is transferred to the return side oil passage 70 via oil passages (not shown) provided in the shaft cylinder 61 and gear case 60. The oil in the annular groove 76 is guided to the return side oil passage 70 via an oil passage (not shown) provided in the gear case body 65.

As shown in FIG. 1, the variable displacement fluid pump A and the constant displacement hydraulic motor B for driving the rear wheels are connected by a connecting member 15 which also serves as a chain stay. As shown in FIG. 7, a discharge side oil passage 78 and a suction side oil passage 79 are formed in this connecting member 15, and the discharge side oil passage 26 of the hydraulic pump A is connected to the discharge side oil passage of the connecting member 15. Hydraulic motor B via 78
At the same time, the return side oil passage 70 of the hydraulic motor B is connected to the suction side oil passage 23 of the hydraulic pump A via the suction side oil passage 79 of the connecting member 15.

FIG. 9 shows an example of a swivel joint (a rotatable joint for an oil passage) 80 provided in the head pipe 4. Reference numeral 83 is a joint case, and the joint case 83 has a hollow cylindrical shape, and its inner periphery is Two annular grooves 84, 85 are formed on the surface, and these annular grooves 84, 85 are connected to oil passages 81, 82 connected to the hydraulic pump A. 86 is a round bar-shaped rotating body that rotatably fits into the joint case 83, and this rotating body 86 has two oil passages 8.
7, 88 are provided, and these oil passages 87, 88
The lower opening of each is a hydraulic motor B for front wheel drive.
The oil passages 81 and 82 are connected to the oil passages 81 and 82. The lower end of this rotating body 86 is connected to the front fork 2.
The upper end portion is connected to the handle post 3a via a connecting pin 89. Note that 90 is an O-ring and 91 is a washer.

The joint case 83 may be fixed within the head pipe 4 or may be formed integrally with the head pipe 4. The oil passages 81 and 82 connected to the joint case 83 may be provided in the main pipe 5 as shown in FIG. 1, and the oil passages 81 and 82 connected to the rotating body 86 may be provided as shown in FIG. It may be provided within the front fork 2. In addition, oil passages 81, 8
2 can also be formed by dividing the inside of the front fork 2 into two.

As described above, as shown in FIG. It is connected to the pressure side oil passage 68 of the hydraulic motor B for front wheel drive through the oil passage 81 inside the front fork 2, and the return side oil passage 70 of the hydraulic motor B is connected to the inside of the head pipe 4 through the oil passage 82 inside the front fork 2. lead to the swivel joint 80, and further connect the main pipe 5
It is connected to the suction side oil passage 23 of the hydraulic pump A via the suction side oil passage 82 inside.

Next, the operation of this embodiment configured as described above will be explained. When the pedal 10 of the bicycle shown in FIG. 1 is depressed to rotate the crankshaft 8, the inner eccentric cam 30 fixed to the crankshaft 8 via the key 31 is rotated to the crankshaft 8, as shown in FIGS. 2 and 3. rotates as one. When the cam 30 rotates, the inner internal gear 33 formed integrally with the cam 30 rotates in the direction of arrow E in FIG. arrow F
Rotate in the direction of. If this gear 43 rotates,
Since the center gear 40 that meshes with this rotates in the direction of arrow G, the fixed gear 41 that meshes with this center gear 40 rotates in the direction of arrow H, and as a result, it meshes with this fixed gear 41. The outer internal gear 38 rotates in the direction of arrow I. In this case, since the rotations of the gears 43 and 41 are exactly the same, the inner internal gear 33 and the outer internal gear 38 rotate integrally.

When the outer internal gear 38 rotates, the disc portion 37 shown in FIG. 4 or 5 rotates in the direction of arrow I, and as a result, the notched groove 36 (in the case of FIG. The protrusion 35, which is engaged with (via), also rotates in the direction of arrow I. Since the projecting piece 35 and the outer eccentric cam 34 are integrally formed, the outer eccentric cam 34 and the inner eccentric cam 30 rotate almost integrally. Here, the term "almost integral" means that the projecting piece 35 is approximately 90 mm wide as shown by the imaginary line in FIG.
This is because, when rotated, the disc portion 37 lags in rotation by an angle θ (approximately 6 degrees in this embodiment). However, at rotational phases of 180° and 360°, the rotational angles of the protruding piece 35 and the disc portion 37 completely match, so it is safe to assume that the inner eccentric cam 30 and the outer eccentric cam 34 rotate together. Note that in order to reduce the angle θ mentioned above, the inner eccentric cam 30
What is necessary is to set the amount of eccentricity to the minimum necessary amount.

Further, in order to change the combined eccentricity of the eccentric cams 30 and 34, the eccentric operation lever 47 shown in FIG.
For example, operate in the direction of arrow J. Then, the sector gear 46 rotates in the direction of the arrow K using the shaft 47a as a fulcrum, causing the gear 45 that meshes with it to rotate in the direction of the arrow G, and as a result, the arm 44 integrated with the gear 45 rotates in the direction of the arrow L. make it move. However, in this case, if the crankshaft 8 is stationary, the inner internal gear wheel 33 is also stationary, so the arm 44 is positioned at the arrow L.
When rotated as shown, the rocking gear 43 rotates in the direction of arrow F and revolves in the direction of arrow L. Therefore, the center gear 40 rotates in the direction of arrow G, and as a result, the fixed gear 41 is rotated in the direction of arrow H, and the outer internal gear 38 that meshes with it is rotated by arrow I.
Rotate in the direction of In this case, since the inner internal gear 33 is stationary as described above, the outer internal gear 38 eventually rotates by a predetermined angle with respect to the inner internal gear 33. In other words, the inner eccentric cam 3
The outer eccentric cam 34 will rotate with respect to 0.

2 and 3 show the state in which the combined eccentricity of the cams 30 and 34 is maximum, so if the outer eccentric cam 34 rotates with respect to the inner eccentric cam 30 from this state, the combined eccentricity The degree gradually decreases.

Then, as shown in FIG. 2, the inner eccentric cam 30
If the eccentricity of is l ₁ and the eccentricity of the outer eccentric cam 34 with respect to the inner eccentric cam 30 is l ₂ , then l ₁ = l ₂
If the outer eccentric cam 34 rotates 180 degrees from the maximum resultant eccentricity with respect to the inner eccentric cam 30, the resultant eccentricity becomes zero.

That is, the degree of eccentricity of the composite eccentric cams 30, 34 can be set arbitrarily from the maximum eccentricity shown in FIGS. 2 and 3 to a state where the amount of eccentricity is zero.

Note that although the above description of the eccentric operation has been made with respect to the case where the crankshaft 8 is stationary, this eccentric operation is performed even when the crankshaft 8 is rotating in exactly the same way as in the stationary state described above. be.

As described above, when the inner eccentric cam 30 and the outer eccentric cam 34 rotate almost integrally due to the rotation of the crankshaft 8, the cam follower 2, which is in contact with the outer eccentric cam 34 by the action of the coil spring 22,
1, each plunger 20 connects to each cylinder hole 19 through
It reciprocates inside as shown by arrows M and N in FIG. 2 by the action of a cam. That is, when the plunger 20 moves in the direction of the arrow, oil enters the cylinder hole 19 from the suction side oil passage 23 via the check valve 27, and when the plunger 20 moves in the direction of the arrow N, the oil enters the cylinder hole 19 through the check valve 27. Pressure oil is pushed out to the discharge side oil passage 26 via. When the crankshaft 8 rotates once, each plunger 20 operates for one cycle, so that the oil discharged from each plunger 20 is transferred to the discharge side oil passage 26.
leaks to.

This spilled oil enters the pressure side recess 67 via the discharge side oil passages 78, 81 and the pressure side oil passage 68 of the hydraulic motor B shown in FIG. Therefore, the large diameter gear 58 rotates in the direction of arrow O in FIG. 7, and the small diameter gear 59 rotates in the direction of arrow P.

The rotation of the large-diameter gear 58 is transmitted to the drive wheel hub 57 via the one-way clutch 64 in FIG. 8, so that in the case of FIG. be able to.

Note that when the gears 58 and 59 rotate as described above, oil flows out into the return side oil passage 70 via the oil drain side recessed part 69, and this oil flows out into the suction side oil passage 79,
The oil is returned to the suction side oil passage 23 in the hydraulic pump A via 82.

The oil leaked during the above operation is returned to the suction side oil passage through the oil passage 29, the annular grooves 72 and 76, and the oil passage (not shown) in the case that communicates with them. There is no risk of it being washed away.

Moreover, if the oil tank 25 is provided in the vertical pipe 6 as described above and the oil tank 25 and the suction side oil passage 23 of the hydraulic pump A are communicated,
Even if there is some spilled oil, the oil tank 25
Since it is refilled from within, the device can be used for long periods without needing lubrication.

Moreover, since the hydraulic motor B of this embodiment uses only two seal rings as the shaft sealing device, it is possible to reduce the rotational frictional resistance of the gear 58 and improve the transmission efficiency.

The gear 58 has a large diameter and the gear 59 has a small diameter because the gear 58, which is integrated with the output shaft 63, is fitted onto the hub shaft 14 or 11 and has a certain diameter in order to transmit power to the hub 57. In addition, there is a design limit to the amount of oil discharged per one rotation of the crankshaft 8 of the hydraulic pump A, so the amount of oil discharged per one rotation of the hydraulic motor B cannot be increased too much. was made smaller.

This has the advantage that the entire device can be made smaller and its external shape can also be improved.

Also, the ratio between the discharge amount of hydraulic pump A and the amount of oil discharged from hydraulic motor B determines the rotation of the drive wheel relative to the rotation of the crankshaft 8, so this ratio must be set to a ratio suitable for each bicycle. No. For example, the maximum discharge volume of hydraulic pump A is 60 c.c. per revolution.
and the oil discharge volume of hydraulic motor B is 15 per rotation.
cc, the oil discharge volume of the two front and rear hydraulic motors B will be 30 c.c., so in the bicycle shown in Figure 1, when the eccentric cam is at its maximum eccentricity, one revolution of the crankshaft will rotate the drive wheel twice. can be done.

Therefore, in this bicycle, if the degree of eccentricity of the cam is adjusted by the eccentric operation of the eccentric cam described above, the discharge amount of the hydraulic pump A can be increased or decreased, and the rotation ratio of the drive wheel to the rotation of the crankshaft can be adjusted. , it is possible to continuously change the speed up to zero within the maximum rotation ratio mentioned above. That is, the rotation speed of the crankshaft:the rotation speed of the driving wheels can be varied steplessly in the range from, for example, 1:2 to theoretically 1:0.

Next, the operation of the automatic transmission actuating device D of this embodiment will be explained. The above-mentioned operation of the eccentric operation lever 47 can of course be carried out by a conventional manual operation, but in the case where the automatic transmission actuating device D is provided as in this embodiment shown in FIG.
The hydraulic pressure in the discharge side oil passage 26 of the flexible hose 5
4 on the pressure chamber 53 in the cylinder 48.

To run a bicycle, the crankshaft 8 is rotated by depressing a pedal, and in this case, the oil pressure generated in the discharge side oil passage 26 of the hydraulic pump A increases or decreases in proportion to the magnitude of the rotational torque by the crank arm 9. That is, when the driving resistance force of the bicycle is large, the oil pressure acting on the pressure chamber 53 becomes high, and when the driving resistance force is small, the oil pressure acting on the pressure chamber 53 becomes low.

Therefore, as shown in FIG. 6, when the gear ratio is in the standard (midpoint of the gear ratio)
9 is at the midpoint of the operating range, and the pressure chamber 5 at that time
If the thrust of the piston 49 and the spring reaction force of the coil spring 52 are set to be in balance due to the oil pressure acting on the pressure chamber 3, if the driving force increases from the standard state, the oil pressure in the pressure chamber 53 will decrease. Because the piston 49 and piston rod 50 are higher, the arrow Q
As a result of the movement in the direction, the eccentricity of the composite cam formed by the eccentric cams 30 and 34 becomes smaller as described above. Therefore, as a result of a decrease in the discharge amount of the hydraulic pump A, the rotational magnification of the front wheels 1 and the rear wheels 13 driven via the hydraulic motor B with respect to the crankshaft 8 automatically decreases. In other words, when the crank pedal 10 becomes heavier, the gear ratio is automatically set to a lower magnification.

Conversely, if the driving force decreases from the standard state described above, that is, if the pedal becomes lighter, the oil pressure in the pressure chamber 53 within the cylinder 48 will decrease, causing the piston 49 and piston rod 50 to move in the direction of arrow R in FIG. As a result, the eccentric cams 30, 34
As the eccentricity of the composite cam increases due to this, the discharge amount of the hydraulic pump A increases. Therefore, the rotational magnification of the front wheels 1 and the rear wheels 13, which are driven via the hydraulic motor B, relative to the crankshaft 8 automatically increases. That is, when the crank pedal 10 becomes lighter, the gear ratio automatically becomes higher.

Therefore, according to the present invention, it is possible to easily make the bicycle continuously variable and even automatic.

Further, FIG. 10 shows another embodiment of the present invention, in which the same reference numerals as those described above indicate equivalent parts. In this system, a hydraulic motor B is attached to the front wheel 1 and a rear wheel 13, respectively, a hydraulic pump A is attached around the crankshaft 8, a three-way switching valve 92 is attached to the hydraulic pump A, and the hydraulic pressure on the rear wheel side is The motor B is connected to the hydraulic pump A via the aforementioned connecting member 15 and the three-way switching valve 92, and the hydraulic motor B on the front wheel side is connected to the swivel joint 8 provided in the head pipe 4.
It is connected to a hydraulic pump A through oil passages 81 and 82 via a three-way switching valve 92 and a three-way switching valve 92.

Figures 11a, b, and c are explanatory diagrams showing each switching state of the three-way switching valve 92. In the case shown in a, the front and rear wheels can be driven simultaneously, and in the case shown in b, only the rear wheels can be driven. In the case shown in c, only the front wheels can be driven.

Therefore, in this case, a drive system suitable for all conditions of the bicycle can be easily obtained by switching a single valve, which is very convenient as a multi-purpose bicycle.

Further, FIG. 12 shows an embodiment of the present invention in which the bicycle is equipped with a small engine, where 93 is a small engine, 94 is a drive pulley provided on its output shaft, and 95 is a bicycle equipped with a small engine.
is a driven pulley provided on the crankshaft 8, and 96 is a V-belt stretched between these pulleys 94 and 95.

As described above, the present invention can be applied to a power-driven two-wheeled vehicle, and since the above-described automatic continuously variable transmission is possible in this case as well, it can be said that the scope of use of the present invention is extremely wide.

(Effects of the Invention) As described above, in the present invention, since the front and rear wheels can be driven together, the conventional rear-wheel drive two-wheel vehicle can be used as a sports vehicle such as a cross-country cycle or a mountain cycle suitable for riding on rough terrain. The effect is that it can demonstrate excellent performance that cannot be obtained with other methods.

In addition, in the present invention, since it is possible to freely select and drive either the front or rear wheels as needed, the motorcycle can be adapted to a drive system suitable for any situation, so it can be used as an all-round motorcycle. It has the advantage of widening the range.

Furthermore, since the present invention transmits power via fluid (for example, pressure oil), the sprocket and chain required in conventional two-wheeled vehicles are completely unnecessary.

In addition, by steplessly changing the discharge volume of the variable displacement fluid pump, stepless speed change can be easily achieved, noise and pulsation can be reduced, and a wide range of gear ratios can be easily achieved. be able to.

Furthermore, in the fluid transmission two-wheeled vehicle of the present invention, since fluctuations in the driving force of the vehicle immediately appear as changes in the pressure of the transmission fluid, the discharge amount of the variable displacement fluid pump is controlled in accordance with this pressure change. For example, it has many excellent effects, such as the ability to easily realize automatic gear shifting.

[Brief explanation of the drawing]

Fig. 1 is a side view of a bicycle showing an embodiment of the present invention, Fig. 2 is a longitudinal sectional front view showing an embodiment of the variable displacement hydraulic pump, and Fig. 3 is a longitudinal sectional side view thereof.
4 is a sectional view taken along the - line in FIG. 3, FIG. 5 is a modified example of FIG. 4, FIG. 6 is a partial cross-sectional rear view taken along the - line in FIG. 8 is a sectional view taken along the line - in FIG. 7, FIG. 9 is a sectional view showing an example of a swivel joint, and FIG. 10 is a sectional view showing an example of a swivel joint. Figures 11a, b, and c are explanatory diagrams of the operation of the three-way switching valve in Figure 10, and Figure 12 is a side view of a bicycle showing another embodiment of the present invention. FIG. 1...Front wheel, 2...Front fork, 3...
Handle, 4...Head pipe, 5...Main pipe, 6...Standing pipe, 7...Hanger pipe, 8
...Crankshaft, 9...Crank arm, 10...
...Pedal, 11...Front wheel hub axle, 13...Rear wheel,
14... Rear wheel hub axle, 15... Connection member, 78,
79...Oil road, 80...Swivel joint,
81, 82...Oil passage, 92...Three-way switching valve, A...
...variable displacement hydraulic pump (variable displacement fluid pump), B...constant displacement hydraulic motor (constant displacement fluid motor), C... eccentric control device, D... automatic transmission actuating device.

Claims (1)

[Claims] 1. An inner eccentric cam is fixed to the central shaft, and an outer eccentric cam is rotatably fitted to the outer periphery of the inner eccentric cam, and an internal gear wheel centered on the central shaft is formed integrally with the inner eccentric cam. , an internal gear identical to this internal gear is arranged concentrically with an internal gear integral with the inner eccentric cam so as to rotate together with the outer eccentric cam, and rotatably with each other, and is centered on the central axis. A gear is rotatably provided, gears that mesh with the center gear and the one internal gear are pivotally supported on a fixed shaft, and the same gear is connected to the center gear and the other internal gear. The eccentric cam is designed to mesh with the wheels, and is pivoted to the free end of an arm that is rotatably supported on the central axis, and by rotating this arm, the eccentricity of the eccentric cam is controlled steplessly. A variable displacement fluid pump using a cam is provided at the input part of the transmission system of a two-wheeled vehicle, fixed displacement fluid motors are provided for each of the front and rear wheels, the fluid pump and the fluid motor are connected by an oil passage, and the oil passage A front and rear wheel drive two-wheeled vehicle characterized by having a switching valve installed inside so that drive of the front and rear wheels can be selected.