JPH08207873A - Auxiliary power-assisted bicycle - Google Patents

Abstract

PURPOSE: To prevent generation of noise during operation and to increase the riding comfortableness by increasing machining preciseness as well as reducing the production cost of the differential device and by setting a ratio of a man power to an auxiliary power near 1 to 1 without impairing power transmission efficiency, also by making accurate the input timing of the man power and auxiliary power. CONSTITUTION: An auxiliary power generating means (electric motor 53) is arranged coaxially with a differential device 54 which outputs a combined power of the power from a crank shaft 33 and an auxiliary power to drive wheel side, and the auxiliary power is so constituted as to input into the differential device 54 through gears (66, 79, 90, and 91). Also the input parts of the differential device 54 are a man power input gear 69 provided rotatably with the crank shaft 33 and an auxiliary power input gear 72 provided rotatably. Then a first planetary gear 76 meshed with the man power input gear 69 and a second planetary gear 77 meshed with the auxiliary power input gear 72 are held rotatably on a differential carrier 74 on which an output part is provided rotatably around the crank shaft 33 under the condition that they are meshed with each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a bicycle body equipped with auxiliary power generation means such as a small engine and an electric motor, and assists human power with the power to drive uphill or run while receiving headwinds. The present invention relates to an easily assisted power assisted bicycle.

[0002]

2. Description of the Related Art In such an auxiliary power assisted bicycle, it is necessary to provide a power combining means for combining human power and auxiliary power and efficiently transmitting the resultant force to driving wheels. Figure 12
And FIG. 13 shows an example of power combining means in a conventional auxiliary power assist type bicycle (auxiliary power assist type vehicle).

The conventional example shown in FIG. 12 is disclosed in Japanese Patent Laid-Open No. 55-164582, and a planetary gear device is used as a power synthesizing means. This planetary gear device a has a sun shaft d having a sun gear b fixed at one end and a sprocket c fixed at the other end, a tubular member e coaxially supported by the sun shaft d, and the tubular member e. A plurality of planet gears g supported by a plurality of support shafts f erected at one end of the cylindrical member e and meshed with the sun gear b, a sprocket h provided at the other end of the cylindrical member e, and a planet gear g. And a sprocket j provided on the outer peripheral portion of the ring gear i.

In the planetary gear device a, auxiliary power from an engine, an electric motor or the like is input from the chain k to the sprocket c, and human power (pedal pedal force) is input from the chain l to the sprocket j. As a result, the sun gear b
And the ring gear i rotate in the same direction, and each planet gear g meshed between the gears b and i revolves around the sun axis d to rotate the tubular member e and the sprocket h. Then, the rotation of the sprocket h is transmitted to the drive wheels via the chain m. When there is a difference in rotation speed between the sun gear b and the ring gear i, the planet gear g rotates to absorb the rotation speed difference, and the rotational force of the sun gear b and the ring gear i is smoothly transmitted to the tubular member d.

Another conventional example in which a planetary gear device is used as the power synthesizing means is disclosed in Japanese Patent Laid-Open No. 5-319354.

On the other hand, the conventional example shown in FIG.
The differential device α is used as the power synthesizing means. The differential device α is installed on an axle γ of a rear wheel β which is a driving wheel of a bicycle, and a pair of large bevel gears δ and ε rotatably supported on the axle γ so as to face each other. A plurality of small bevel gears ζ provided so as to mesh with the large bevel gears δ and ε, and an inner ring η that pivotally supports each small bevel gear ζ on its inner circumference. An outer ring (rim) κ is coaxially fixed to the outer periphery of the inner ring η via spokes θ, and a tire λ is fitted to the outer ring κ to form a rear wheel β.

A sprocket μ is rotatably integrated with the large bevel gear δ on one side. The sprocket μ is supplied with auxiliary power from auxiliary power generating means such as an engine or an electric motor (not shown) through the chain ν. Is entered. Further, the large bevel gear ε on the other side is provided with a sprocket π via a one-way clutch ξ, and human power, that is, pedaling force is input to the sprocket π via the chain ρ.

When the vehicle is driven only by human power without inputting auxiliary power to the large bevel gear δ, the large bevel gear δ is used.
Is stopped and only the large bevel gear ε rotates, so a rotation difference (differential) occurs between the large bevel gear δ and the large bevel gear ε,
Each small bevel gear ζ revolves around the large bevel gears δ and ε while rotating. The revolution speed of the small bevel gear ζ becomes the rotation speed of the inner wheel η, that is, the rear wheel β. In this case, the rotation speed of the rear wheel β is half the rotation speed of the large bevel gear ε.

When auxiliary power is input to the large bevel gear δ in this state, the rotation difference between the large bevel gear δ and the large bevel gear ε becomes small, and the rotation speed of each small bevel gear ζ becomes slower. The revolution speed becomes faster. In this way, the human power and the auxiliary power are combined and transmitted to the rear wheel β, and the pedal effort is reduced.

By the way, such an auxiliary power assisted bicycle is treated as a motorized bicycle unless it is set so that the assist ratio of assist power (ratio between human power and auxiliary power) does not always exceed human power. In addition to being obliged to obtain a driver's license and register a vehicle, it is impossible to drive on a road other than the roadway, which greatly impairs the convenience of a bicycle.

Therefore, in order to allow the rider to easily ride the bicycle while maximally utilizing the assist by the auxiliary power, it is necessary to always set the assist ratio to around 1: 1.

[0012]

However, when the planetary gear device a is used as the power synthesizing means as shown in FIG. 12, the sun gear b is required to set the assist ratio to around 1: 1.
On the other hand, since the ring gear i has to be rotated, there is a concern that the power transmission efficiency may decrease due to gear meshing loss due to rotation of the planetary gear g.

On the other hand, when the differential device α is used as in the power synthesizing means shown in FIG. 13, two large bevel gears δ,
If the magnitude of the auxiliary power is controlled so that the rotation speed of ε is synchronized, the ratio of the human power and the auxiliary power can be set to about 1: 1. At that time, since the differential device α does not differential, the power transmission efficiency is extremely high. Good for

However, since the differential device α is installed on the axle γ of the rear wheel β, and the human power and the auxiliary power are transmitted through the chains ν and ρ, respectively, the chains ν and ρ are loosened. This tends to cause a slight delay in the input timing of human power and auxiliary power.

Therefore, even if the magnitude of the auxiliary power is controlled according to the magnitude of human power, smooth power transmission is not performed due to the delay of the input timing, and frequent shocks impair the rideability. Become. This drawback also applies to the planetary gear device a shown in FIG.

Further, the differential device α is made up of a large number of bevel gears, which is difficult to manufacture, and it is necessary to take measures against meshing noise of the bevel gears, resulting in a high manufacturing cost.

Furthermore, since the heavy differential gear unit α is located at the rear portion of the vehicle body, the load on the rear wheels β becomes heavier than that on the front wheels, which may impair running stability and the axle γ of the rear wheels β. There is also a problem that it is not possible to use a cheap internal multi-speed transmission.

The present invention has been made to solve the problems of the conventional auxiliary power assist type bicycle, and the ratio of human power to auxiliary power is set to about 1: 1 without impairing the power transmission efficiency. In addition, it is an object of the present invention to provide an auxiliary power assist type bicycle which can improve the riding performance by accurately inputting the human power and the auxiliary power and can eliminate the fear of impairing the running stability.

Another object of the present invention is to reduce the manufacturing cost of the differential gear, improve the machining accuracy, and prevent the generation of noise during operation of the differential gear.

A further object of the present invention is to construct the differential gear in a lightweight and compact structure.

[0021]

In order to achieve the above object, an auxiliary power assist type bicycle according to the present invention, as described in claim 1, generates a crankshaft which is rotationally driven by human power and an auxiliary power. And a differential device that combines the auxiliary power with the power of the crankshaft and outputs the resultant force to the drive wheel side. The differential device is coaxial with the crankshaft. It is arranged and configured to input auxiliary power to the differential device via gears.

Further, as described in claim 2, a human power input gear in which the input portion of the differential device is rotatably integrated with the crankshaft, and an auxiliary power input gear rotatably provided in the crankshaft are provided. On the other hand, the output part of the differential device is a differential carrier rotatably provided around the crankshaft, and this differential carrier has a first planetary gear that meshes with the human power input gear and a first planetary gear that meshes with the auxiliary power input gear. The two planetary gears were rotatably held in mesh with each other.

When the auxiliary power assisted bicycle is constructed as in claim 1, the human power, that is, the power of the crankshaft and the auxiliary power generated by the auxiliary power generation means are input to the differential device and combined, and the resultant force is obtained. Are taken out from the differential device and output to the drive wheel side.

When the human power and the auxiliary power are combined by using the differential device as described above, the differential device does not make a differential when the ratio of the human power and the auxiliary power becomes 1: 1, so that the power transmission efficiency is improved. Is kept good.

Further, in the present invention, since the differential device is installed coaxially with the crankshaft and the auxiliary power is inputted to the differential device through the gear, the human power and the auxiliary power are respectively supplied. It is directly input to the differential device, which eliminates delay in the input timing of human power and auxiliary power and allows smooth power transmission.

Moreover, since the differential device is located near the center of gravity of the vehicle body, the weight balance of the vehicle body is improved and the running stability of the auxiliary power assisted bicycle is not impaired.

Further, in the case of the second aspect, the human power is input to the human power input gear through the crankshaft,
The auxiliary power from the auxiliary power generation means is input to the auxiliary power input gear, the rotations of the human power input gear and the auxiliary power input gear are transmitted to the differential carrier via the first and second planetary gears, and the differential carrier The rotation is taken out as the resultant force of human power and auxiliary power.

When the rotation speeds of the human power input gear and the auxiliary power input gear are the same, that is, the ratio of the human power to the auxiliary power is 1: 1.
, The first and second planetary gears do not rotate, and the differential carrier rotates at the same rotation speed as the rotation speeds of the human power input gear and the auxiliary power input gear.

In this case, the human power input gear,
Since the auxiliary power input gear and the first and second planetary gears can be composed of spur gears, the manufacturing cost of the differential gear is reduced and the machining accuracy is improved. The generation of noise is also prevented. In addition, the differential device is lightweight and compact.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a left side view of an auxiliary power assisted bicycle according to the present invention.

This auxiliary power assisted bicycle 1 is provided with a parallel tube type vehicle body frame 2, and an auxiliary power assisting device 3 is mounted in the lower center part of the vehicle body frame 2.

The vehicle body frame 2 has a head pipe 4 located at the front of its head, and an upper tube 5 and a lower tube 6 extend in parallel to the rear pipe obliquely downward from the head pipe 4. The middle portion of the upper tube 5 and the vicinity of the rear end portion of the lower tube 6 are connected by a reinforcing material 7, and the rear end portion of the upper tube 5 is joined to the lower end portion of a seat tube 8 provided at a steep angle via a seat lug 9. To be done.

A pair of left and right joint tubes 11 extend downward from the seat lug 9, the lower end of the joint tube 11 is opened left and right, and a pipe-shaped chain lug 12 extending in the vehicle width direction is fixed. There is. Then, from the chain lug 12, a pair of left and right chain stays 13
Extends rearward.

On the other hand, a pair of left and right seat stays 14 extends rearward and obliquely downward from the vicinity of the upper end portion of the seat tube 8, and the lower end portions of these seat stays 14 are connected to the rear end portion of the chain stay 13 via the rear end 15. Is joined to.

The rear end of the lower tube 6 and the chain lug
A front bracket 16 and a rear bracket 17 are fixed to the lower part of 12 respectively.
Auxiliary power assist device 3 is fixed to 7 with bolts. Therefore, the rear end portion of the lower tube 6 is connected to the chain lug 12 via the auxiliary power assist device 3, and the auxiliary power assist device 3 also serves as a structural member of the vehicle body frame 2.

A front fork 19 is rotatably supported by the head pipe 4 of the vehicle body frame 2, and a front wheel 20 is supported on a lower end portion of the front fork 19. A handlebar 22 is fixed to the upper part of the front fork 19 via a handle post 21, and the front fork 19 has a front wheel 20.
A front fender 23 that covers the front fender 23, a front brake 24 for braking the front wheels, a basket 25 for loading luggage, and the like are provided integrally with each other.

A rear wheel 26 is pivotally supported on the rear end 15 located at the rear end of the body frame 2, and a rear fender 27 that covers the rear wheel 26 is fixed to the chain stay 13, the seat stay 14 and the rear end 15. A rear brake 28 for braking the rear wheels is provided on the seat stay 14. The rear end
15 is also provided with a stand device 29 for erecting the vehicle body when parked.

A seat post 31 is inserted into and fixed to the seat tube 8 from above, and a saddle 32 is attached to an upper end portion of the seat post 31. On the other hand, the auxiliary power assist device 3 is rotatably supported by a crank shaft 33 extending in the vehicle width direction. The crank 34L and the crank 34R are fixed to both ends of the crank shaft 33, and the cranks 34L and 34R are provided at the tips thereof. Each has a pedal 35.

A drive sprocket 36 located on the right side of the auxiliary power assist device 3 is axially mounted on the crankshaft 33, and between the drive sprocket 36 and the driven sprocket 37 provided on the rear wheel 26. Chain 38
Is wrapped around.

The crankshaft 33 is rotationally driven in the forward rotation direction indicated by the arrow when an occupant seated on the saddle 32 steps on the pedal 35 with his / her foot, and the drive sprocket 36 is a crankshaft.
It rotates in the same direction as 33, and this rotation is transmitted to the driven sprocket 37 by the chain 38 to drive the rear wheel 26.

A battery package 40 for operating an electric motor incorporated in the auxiliary power assist device 3 is fixed between the upper tube 5 and the lower tube 6 of the vehicle body frame 2. This battery package 40
Has, for example, a configuration in which fifteen batteries 41 and a charger (not shown) are enclosed in a battery case 42 made of synthetic resin. A control device 43 for controlling the output of the electric motor is attached to the upper part of the auxiliary power assist device 3 (see also FIG. 3).

FIG. 2 is a transverse cross-sectional view of the auxiliary power assist device 3 developed along the line II-II of FIG. 1, and FIG.
FIG. 3 is a vertical sectional view taken along line III-III of FIG. The casing 44 forming the outer shell of the auxiliary power assist device 3 is made of, for example, an aluminum alloy, and has a left case half body 44L as shown in FIG.
The case half body 44R on the right side is joined with a bolt or the like.

The inner space of the casing 44 is divided into an electric motor chamber 46 on the front side and a differential device chamber 47 on the rear side with a partition wall 45 as a boundary, and the crankshaft 33 has a bearing 4 at the center of the differential device chamber 47.
It is rotatably supported by 8,49.

Cranks 34L and 34R are fixed by bolts 51 to both ends of the crankshaft 33 which projects left and right from the casing 44. A sprocket boss 52 is rotatably mounted on the right side of the crankshaft 33, and a drive sprocket 36 is fixed to the sprocket boss 52 so as to rotate integrally therewith.

In the electric motor chamber 46, the above-mentioned electric motor 53
And the differential device 54 is installed in the differential device chamber 47. The electric motor 53 serves as auxiliary power generation means for generating auxiliary power, and the differential device 54 combines the auxiliary power of the electric motor 53 and the power (human power) of the crankshaft 33 to form the rear wheel 26 as a drive wheel. Is a means for synthesizing power to be transmitted to.

The coil 55 of the electric motor 53 is a case half body 44R
It is fixed to the side with bolts 56, and the main shaft 57 of the electric motor 53
Is rotatably supported by bearings 58 and 59 parallel to the crankshaft 33, and a magnet rotor 60 is provided integrally with the main shaft 57 for rotation. The magnet rotor 60 is formed in a bowl shape surrounding the coil 55, and when the electric motor 53 is operated, the magnet rotor 60 orbits the coil 55 and drives the main shaft 57 to rotate.

A roller type planetary speed reduction mechanism 62 is provided on the left side of the electric motor 53. The planetary reduction mechanism 62 includes a ring roller 63 fixed to the case half body 44L and, for example, four planetary rollers 64 contacting the inner peripheral surface of the ring roller 63.
And a deceleration carrier 65 that rotatably supports the planet rollers 64, and a primary drive gear 66 is rotatably provided on the left side of the deceleration carrier 65.

A sun roller 67 is concentrically formed on the left end of the main shaft 57 of the electric motor 53, and the sun roller 67 is press-fitted between four planet rollers 64. Therefore, when the main shaft 57 rotates, each planetary roller 64 revolves around the sun roller 67 while rotating between the fixed ring roller 63 and the rotating sun roller 67.
65 is decelerated, and the primary drive gear 66 rotates integrally with the deceleration carrier 65. The main shaft 57 of the electric motor 53
Like the crankshaft 33, the (sun roller 67) rotates in the forward direction indicated by the arrow, and the primary drive gear 66 also rotates in the same direction.

By the way, the planetary reduction mechanism 62 is of a roller type. For example, a pinion gear is provided on the outer periphery of the sun roller 67, the ring roller 63 is changed to a ring gear (internal gear), and each planetary roller 64 is replaced. The planetary reduction mechanism 62 may be configured as a gear type by changing to a planetary gear that meshes with the pinion gear and the ring gear.

FIG. 4 is a conceptual diagram of the mechanism of the auxiliary power assist device 3 showing one embodiment of the present invention. As shown in FIGS. 2 to 4, the differential 54 is arranged coaxially with the crankshaft 33.

The differential device 54 is constructed as follows. First, inside the sprocket boss 52 that is rotatably supported by the crankshaft 33, a human power input gear 69 is rotatably integrated with the crankshaft 33 by spline coupling or the like. A cylindrical clutch sleeve 70 is inserted on the left side of the human power input gear 69 so as to be rotatable with respect to the crankshaft 33 and slidable in the axial direction.

A spline 71 is formed on the outer peripheral portion of the clutch sleeve 70, and an auxiliary power input gear 72 is fitted to the spline 71. Therefore, the auxiliary power input gear 72 is rotationally integrated with the clutch sleeve 70, is slidable in the axial direction of the clutch sleeve 70, and can rotate around the crankshaft 33 together with the clutch sleeve 70.

Human power input gear 69 and auxiliary power input gear 72
Are gears that are input portions of the differential device 54 and have the same number of teeth.

A dog clutch 73 is provided between the clutch sleeve 70 and the human power input gear 69. The dog clutch 73 is engaged when the clutch sleeve 70 slides to the human power input gear 69 side and the clutch sleeve 70 is engaged. And human power input gear
69 and the rotation united.

A differential carrier 74 is rotatably provided around the crankshaft 33. This differential carrier 74
Is an output portion of the differential device 54, and is composed of a left carrier half body 74L and a right carrier half body 74R. The carrier half body 74L is attached to a carrier boss 75 integrally formed on the left side portion of the auxiliary power input gear 72. The carrier half body 74R is rotatably supported by rotation, and is integrally fixed to the sprocket boss 52 by spline coupling or the like. In addition, in FIG.
The differential carrier 74 is omitted in a bold line shape to facilitate understanding of the structure of FIG.

The differential carrier 74 rotatably holds a pair of first planetary gears 76 meshing with the human power input gear 69 and a pair of second planetary gears 77 meshing with the auxiliary power input gear 72. The first planetary gear 76 and the second planetary gear 77 are meshed with each other. The first planetary gear 76 and the second planetary gear
77 teeth have the same number of teeth.

FIG. 5 is a view taken in the direction of arrow V in FIG.
And auxiliary power input gear 72 and first and second planetary gears 76,77
Shows the positional relationship (the differential carrier 74 is not shown).
In this embodiment, the first planetary gear 76 and the second planetary gear 77 are supported by the differential carrier 74 in pairs, but two or more pairs may be provided, for example.

A secondary driven gear 79 is provided on the left side of the differential device 54 thus configured. The secondary driven gear 79 is supported adjacent to the clutch sleeve 70 so as to be rotatable with respect to the crankshaft 33 and immobile in the axial direction. A dog clutch 80 is provided between the secondary driven gear 79 and the clutch sleeve 70. This dog clutch 80 is engaged when the clutch sleeve 70 slides toward the secondary driven gear 79 side,
The 70 and the secondary driven gear 79 are integrally rotated.

On the left side of the secondary driven gear 79, a disk-shaped sensor plate 81 is provided so as to rotate integrally with the crankshaft 33, and notches 82 are equidistantly provided on the outer peripheral portion of the sensor plate 81. Has been formed. On the other hand, a crankshaft rotation sensor 83 facing the outer peripheral portion of the sensor plate 81 is installed in the casing 44 (case half body 44L).
Therefore, when the crankshaft 33 rotates, the sensor plate
81 rotates integrally, and the crankshaft rotation sensor 83 counts the notches 82 in the sensor plate 81 to detect the rotation speed of the crankshaft 33.

Further, the main shaft 57 and the crank shaft of the electric motor 53
An idle shaft 84 is erected between the shafts 33 and 33, and both ends thereof are fixed to the casing 44 by spline coupling or the like. The idle shaft 84 is provided with a one-way clutch 85, and the outer turbo 86 of the one-way clutch 85 is axially supported by the idle shaft 84 by bearings 87 and 88.The outer turbo 86 has a large primary driven gear 90 and a small diameter. The secondary drive gear 91 is provided integrally with the rotation.

The primary driven gear 90 is the primary drive gear 66.
, The secondary drive gear 91 is the secondary driven gear 79
Meshes with. Further, the one-way clutch 85 permits the primary driven gear 90 and the secondary drive gear 91 to rotate only in the direction of the arrow shown in FIG.

Therefore, the auxiliary power from the electric motor 53 is transmitted to the planetary speed reduction mechanism 62, the primary drive gear 66, the primary driven gear 90, the secondary drive gear 91, and the secondary driven gear 79 in this order, and the speed is reduced in three stages to the clutch. Sleeve 70
Is transmitted to

As shown in FIGS. 2 and 4, when the clutch sleeve 70 slides toward the secondary driven gear 79 and the dog clutch 80 is engaged, the rotation of the secondary driven gear 79 is assisted via the clutch sleeve 70. Input to the power input gear 72. Further, the human power, that is, the force with which the occupant depresses the pedal 35 is input to the human power input gear 69 via the cranks 34L and 34R and the crankshaft 33.

When the auxiliary power assisted bicycle 1 is run only by human power without operating the electric motor 53, the crankshaft 33 is rotationally driven by human power in the forward rotation direction (direction of arrow), and the human power input gear 69 is moved. As the differential carrier 74 is stopped by the load from the rear wheel 26 when it rotates together with the crankshaft 33, the rotation of the human power input gear 69 is changed to the first planetary gear.
An attempt is made to reverse the auxiliary power input gear 72 via the 76 and the second planetary gear 77.

However, since the reverse rotation of the auxiliary power input gear 72 is blocked by the one-way clutch 85 provided on the idle shaft 84, the first planetary gear 76 and the second planetary gear are relatively moved.
77 revolves around the human power input gear 69 and the auxiliary power input gear 72, which causes the differential carrier 74 to rotate in the forward rotation direction of the crankshaft 33 at a rotation speed of one half of the crankshaft 33 (differential device). 54 is differential). When the differential carrier 74 rotates, the drive sprocket 36 integrally rotates to drive the rear wheel 26, and the auxiliary power assisted bicycle 1 runs.

When the electric motor 53 operates in this state,
Since the auxiliary power input gear 72 receives the auxiliary power of the electric motor 53 and rotates in the same direction as the human power input gear 69, the first planetary gear
Revolution speed of 76 and second planetary gear 77, that is, differential carrier
The rotation speed of 74 is increased, human power and auxiliary power are combined, the resultant force is taken out from the differential carrier 74, and the drive sprocket 36 is driven.

Therefore, the pedaling force of the pedal 35 is greatly reduced by the assist of the auxiliary power, and the traveling becomes very easy. When the human power input gear 69 and the auxiliary power input gear 72 have the same rotational speed, that is, when the differential device 54 stops differential, the ratio of the human power to the auxiliary power becomes 1: 1 and the ideal power It becomes a ratio.

By the way, the differential 54 includes a switching mechanism.
92 is provided. This switching mechanism 92 is a manual power input gear.
Differential device by blocking relative rotation between 69 and auxiliary power input gear 72
This mechanism locks the differential of 54 and separates the power transmission system from the planetary reduction mechanism 62 to the secondary driven gear 79 from the differential device 54. This switching mechanism 92
It also includes a clutch sleeve 70 and dog clutches 73 and 80 provided at both ends of the clutch sleeve 70.

As shown in FIGS. 2 and 6 and 7, at the left end of the clutch sleeve 70, a switching ring 93 is rotatably attached to the clutch sleeve 70 via a bearing 94, and three circlips 95, It is fixed in the axial direction using 96 and 97.

The left side of the switching ring 93 and the case half body 44
A thrust cam 99 is formed between the L inner panel 44a and the thrust cam 99. The shape of the thrust cam 99 is as shown in FIG. 8 when the switching ring 93 rotates in the rotation direction of the crankshaft 33. 93 is separated from the inner panel 44a by a distance W.

The switching ring 93 is integrally formed with a lever 100 protruding in the circumferential direction.
The cable bridge 102 is provided by 101 so that it can be swung freely, and the inner cable 10 of the operation cable 103 is
4 The end part is locked.

An operation cable insertion boss 105 is formed on the upper portion of the casing 44, and a cable stopper 106 is fixed to this portion using a circlip 107, a fixing plate 108 and a screw 109. Inner cable 10
4 passes through this cable stopper 106 and
The end of 103 outer cable 110 is a cable stopper.
Retained outside of 106. Note that 111 is a waterproof cap.

A return spring 112 is elastically mounted between the cable stopper 106 and the cable receiver 102, whereby the switching ring 93 is urged in the rotation direction opposite to the rotation direction of the crankshaft 33.

The other end of the operation cable 103 has a handle bar 22.
It is connected to an operation unit (not shown) provided on the switch ring 93, etc., and when an occupant operates this operation unit, the inner cable 104 resists the biasing force of the return spring 112 and the switching ring 93.
The lever 100 is pulled to the position 100a, and the switching ring 93 is rotated in the rotation direction of the crankshaft 33. Therefore, the action of the thrust cam 99 causes the switching ring 93 to move to the clutch sleeve 70.
At the same time, it moves to the human power input gear 69 side by a distance W (Fig. 9
See Figure 10).

When the clutch sleeve 70 moves to the human power input gear 69 side in this way, the dog clutch 73 is coupled and the human power input gear 69 and the auxiliary power input gear 72 are integrally rotated via the clutch sleeve 70. Differential
54 differentials are locked. Therefore, the human power input gear 69,
Auxiliary power input gear 72, first planetary gear 76, second planetary gear 77
Will rotate together with the differential carrier 74. Further, the disengagement of the dog clutch 80 separates the power transmission system from the planetary speed reduction mechanism 62 to the secondary driven gear 79 to the differential device 54.

For example, when the auxiliary power of the electric motor 53 is no longer applied (when the battery 41 is completely discharged), the switching mechanism 92 is operated to lock the differential gear 54 as described above. Is transmitted to the drive sprocket 36 without deceleration, so that the pedal 35 can travel without rowing too much, and the rotation resistance and rotation of the power transmission system from the planetary reduction mechanism 62 to the secondary driven gear 79 Since inertial force is not applied to the crankshaft 33, the bicycle can travel as easily as a normal bicycle.

FIG. 11 shows this auxiliary power assisted bicycle 1
3 is a power system diagram of FIG. As described above, the human power, that is, the force with which the occupant steps on the pedal 35 is input to the differential device 54 via the crankshaft 33. On the other hand, the auxiliary power generated by the electric motor 53 is input to the differential device 54 via the planetary speed reduction mechanism 62 and the one-way clutch 85. Then, in the differential device 54, the human power and the auxiliary power are combined, and the resultant force drives the rear wheel 26 via the chain 38.

The rotation speed of the crankshaft 33 is detected by the crankshaft rotation sensor 83 and input to the control device 43. The control device 43 applies the voltage of the battery 41 to the electric motor 53 based on the information about the rotation speed of the crankshaft 33 and the rotation speed of the electric motor 53 which is input from a motor sensor (not shown), so that human power and auxiliary power are constantly applied. The output of the electric motor 53 is controlled so that the power has a one-to-one ratio, that is, a relative rotation difference is not generated between the human power input gear 69 of the differential device 54 and the auxiliary power input gear 72. Further, for example, when the rotation speed of the crankshaft 33 or the electric motor 53 exceeds a certain value, it is considered that the traveling speed becomes excessive and the output of the electric motor 53 is reduced.

When the auxiliary power assisted bicycle 1 starts, a large load is applied to the electric motor 53 and the battery 41
Therefore, the electric motor 53 may be controlled not to operate at the time of starting. In this case, the rotation direction of the auxiliary power input gear 72 of the differential device 54 is regulated by the one-way clutch 85, and the differential carrier 74 rotates at half the rotation speed of the crankshaft 33, so that the pedaling force of the pedal 35 is extremely low. It is very light and can be easily started without the assistance of the electric motor 53.

As described above, when the differential gear 54 is used as the power synthesizing means for synthesizing the human power and the auxiliary power, the differential gear 54 should be differential when the ratio of the human power and the auxiliary power becomes 1: 1. Therefore, the power transmission efficiency is kept good and the life of the battery 41 is extended.

In the present invention, the differential device 54 is used as a crankshaft.
Since it is installed coaxially with respect to 33, and the auxiliary power of the electric motor 53 is input to the differential device 54 via the gears (66, 79, 90, 91), the human power and the auxiliary power are directly supplied. To the differential device 54, and there is no delay in the input timing. For this reason, the auxiliary power can be finely controlled according to human power, and in that case, shock is not generated, smooth power transmission is performed, and riding comfort is greatly improved.

Moreover, since the differential device 54 is located near the center of gravity of the vehicle body, the weight balance of the vehicle body is maintained well, and the running stability of the auxiliary power assisted bicycle 1 is not impaired. Further, it is possible to install another transmission device (for example, a cheap internal transmission or the like) on the axle portion of the rear wheel 26 to further improve the running performance.

Further, according to the present invention, all the gears 69, 72, 76, 77 which constitute the differential gear 54 can be spur gears having good workability. It is possible to greatly contribute to the reduction of manufacturing cost, the improvement of processing accuracy, and the prevention of noise generation during the operation of the differential gear 54. In addition to this, the first planetary gear 76 and the second planetary gear 77 can be made into a common component, and since a large ring gear having inner peripheral teeth is not necessary, the manufacturing cost can be further reduced and the working accuracy can be improved.

Further, since the differential gear 54 is configured to be lightweight and compact, the auxiliary power assist device 3 can be downsized, which further improves the running performance of the auxiliary power assist type bicycle 1 and the maneuverability thereof. You can improve your sex.

Especially, since the human power input gear 69 and the auxiliary power input gear 72 of the differential device 54 are spur gears, both gears 69, 72
Can be narrowed and the differential 54 can be made compact in the vehicle width direction. This is an advantage that a differential device using a bevel gear does not have.

Unlike the differential device using the bevel gear, the differential device 54 can also adjust the ratio of human power and auxiliary power by changing the number of gear teeth. At that time, if the number of teeth of one of the gears meshing with each other is increased and the number of teeth of the other is decreased to make the axial distance unchanged, it is not necessary to change the differential carrier 74, and a large increase in cost can be avoided. You can By adjusting the ratio between the human power and the auxiliary power in this way, the assist amount of the auxiliary power can be adjusted according to the user's leg strength, and the specifications can be made different between a flat area and an area with many slopes.

By the way, although the auxiliary power assisted bicycle 1 is a two-wheeled vehicle in this embodiment, it is not limited to a two-wheeled vehicle and may be, for example, a three-wheeled vehicle or a four-wheeled vehicle.

[0088]

As described above, the auxiliary power assisted bicycle according to the present invention includes a crankshaft that is driven to rotate by human power, auxiliary power generating means for generating auxiliary power, and
A differential device that combines the power of the crankshaft with the auxiliary power and outputs the resultant force to the drive wheels is provided, and the differential device is arranged coaxially with the crankshaft, and the differential device is also provided. It is characterized in that the auxiliary power is input to the gear via a gear.

With such a configuration, human power and auxiliary power are directly input to the differential device, and there is no delay in input timing. For this reason, the auxiliary power can be finely controlled according to human power, and shock is not generated at that time, smooth power transmission is performed, and riding comfort is improved. Moreover, since the differential device is located near the center of gravity of the vehicle body, the weight balance of the vehicle body is improved and the running stability is kept good.

Further, in the auxiliary power assisted bicycle according to the present invention, the input portion of the differential device is a human power input gear provided integrally with the crankshaft for rotation, and the auxiliary power input provided rotatably on the crankshaft. On the other hand, the output part of the differential gear is a differential carrier rotatably provided around the crankshaft, and the differential carrier has a first planetary gear meshing with the human power input gear and the auxiliary power input gear. It is characterized in that the second planetary gears that mesh with each other are rotatably held while meshing with each other.

By doing so, it is possible to make all the gears forming the differential gear a spur gear having good workability, which reduces the manufacturing cost of the differential gear and improves the machining accuracy. A great contribution can be made to the prevention of noise generation during the operation of the moving device.

Further, since the differential device is constructed in a lightweight and compact form, the running performance of the auxiliary power assisted bicycle can be further improved and the maneuverability can be improved.

[Brief description of drawings]

FIG. 1 is a left side view of an auxiliary power assist type bicycle according to the present invention.

FIG. 2 is a cross-sectional view of the auxiliary power assist device, which is deployed along the line II-II in FIG.

FIG. 3 is a vertical sectional view taken along the line III-III in FIG.

FIG. 4 is a mechanical conceptual perspective view of an auxiliary power assist device showing an embodiment of the present invention.

FIG. 5 is a view on arrow V in FIG.

6 is a VI-VI arrow view of FIG. 2.

FIG. 7 is a view on arrow VII of FIG.

FIG. 8 is a view showing a state in which a switching ring is pressed by the action of a thrust cam.

FIG. 9 is a cross-sectional view of the auxiliary power assist device showing a state in which the differential device is locked.

FIG. 10 is a mechanical conceptual perspective view of the auxiliary power assist device showing a state in which the differential device is locked.

FIG. 11 is a power system diagram of an auxiliary power assisted bicycle.

FIG. 12 is a cross-sectional view of a planetary gear device used as a power synthesizing means, showing a conventional technique.

FIG. 13 is a plan view of a bevel gear type differential gear used as a power combining means, showing a conventional technique.

[Explanation of symbols]

 1 Auxiliary power assisted bicycle 2 Body frame 3 Auxiliary power assist device 26 Rear wheel which is a driving wheel 33 Crankshaft 36 Drive sprocket 37 Driven sprocket 38 Chain 41 Battery 43 Control device 53 Electric motor 54 as auxiliary power generation means 54 Differential device 69 Human power input gear 70 Clutch sleeve 72 Auxiliary power input gear 73, 80 Dog clutch 74 Differential carrier 76 First planetary gear 77 Second planetary gear 85 One-way clutch

Front page continuation (72) Inventor Tadashi Matsuura 300, Takatsuka-cho, Hamamatsu-shi, Shizuoka Suzuki Stock Company

Claims (2)

[Claims] 1. A crankshaft 33 which is rotationally driven by human power.
And auxiliary power generation means (electric motor
53) and the power of the crankshaft 33 combined with the above auxiliary power,
A differential device 54 that outputs the resultant force to the drive wheels is provided, and the differential device 54 is coaxially arranged with respect to the crankshaft 33, and auxiliary power is supplied to the differential device 54 by gears (66, 90, 91,79)
An auxiliary power assisted bicycle characterized in that it is configured to input through. 2. The input portion of the differential gear 54 is a human power input gear 69 rotatably integrated with the crankshaft 33 and an auxiliary power input gear 72 rotatably provided on the crankshaft 33, while the differential gear is provided. The output portion of 54 is a differential carrier 74 rotatably provided around the crankshaft 33. The differential carrier 74 includes a first planetary gear 76 meshing with a human power input gear 69 and an auxiliary power input gear 72.
The auxiliary power assist type bicycle according to claim 1, wherein a second planetary gear 77 meshing with the second planetary gear 77 is rotatably held in a state of meshing with each other.