JPH09229100A - Self-exciting type clutch mechanism and power assisting machine for bicycle using the mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely transmit torque of a motor to an output rotary shaft by transmitting rotational torque of the motor to a main torque transmitting plate, and pressure-contacting the main torque transmitting plate with a final output step. SOLUTION: Rotation of a motor is transmitted to the final output step gear 21 of a speed reducer and a former step reduction gear 22, a clutch gear 37 is rotated by the former step reduction gear, a weight plate 38 is engaged with a driven ring 40 by the centrifugal force of the clutch gear, and a driven ring is also rotated. A main torque transmitting plate 27 is rotated by clutch shoes 43 frictionally contacted with the driven ring, a torque transmitting shaft 28 is engaged with the slopes 26a, 28a of a connected main shaft 26 by rotation of the main torque transmitting plate, further the brake material 42 of the main torque transmitting plate is pressure-contacted with the taper face 21b of the final output step gear, and hence the main torque transmitting plate and the final output step gear are strongly pressure-contacted with each other, so as to transmit rotational torque of the motor to the connected main shaft.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-exciting clutch mechanism used in, for example, a power assisting machine for a bicycle with a power assisting machine and a bicycle power assisting machine using the self-exciting clutch mechanism.

[0002]

2. Description of the Related Art Conventionally, there have been two bicycle power assist machines.
There are two types. One is that a drive switch or a control accelerator is provided in the handle portion, and the motor power can be controlled to an arbitrary size by the accelerator, which is called a motorized bicycle and requires a license. The other is to detect the pedal drive torque when pedaling by human power and assist the power equivalent to this drive torque. The ratio of human power and auxiliary power must not exceed 1 up to 15 km / h. Is one of the conditions for being certified as a bicycle, and you can ride without a license.

[0003]

DISCLOSURE OF THE INVENTION In a bicycle equipped with a power assisting machine that can be used without a license, when the pedal driving torque is detected to determine the assisting power, in addition to the means for detecting the pedaling force of the pedal, the assisting power It is necessary to provide an output shaft that couples the output and the pedal output to enable torque transmission only in the forward direction. However, if the output shaft is different from the pedal crank shaft, a bicycle having a special dedicated structure is required, and there is a problem that the bicycle cannot be easily attached to a normal bicycle.

Therefore, according to the first and second aspects of the present invention, the rotational torque of the electric motor is transmitted to the main torque transmission plate and the main torque transmission plate is pressed against the final output stage of the speed reducer. (EN) Provided is a self-excited clutch mechanism that can be reliably transmitted to an output rotary shaft by excitation.

The invention according to claims 3 to 9 is suitable because it can be easily attached to a commercially available ordinary bicycle to improve versatility, and moreover the torque of the electric motor can be reliably transmitted to the petal crankshaft. Provided is a power assisting machine for a bicycle, which uses a self-exciting clutch mechanism capable of various power assisting.

[0006]

According to the first aspect of the present invention,
Due to the rotation of the electric motor, the final output stage of the reduction gear connected to this electric motor rotates, and the main torque transmission plate rotates in frictional contact with this final output stage. The engagement state of the engagement portion provided between the torque transmission shaft fixed by the torque transmission plate and the output rotation shaft is strengthened,
The pressure contact force of the main torque transmission plate to the final output stage increases,
The torque of the electric motor is transmitted to the output rotary shaft.

According to a second aspect of the present invention, a torque transmission shaft fitted to the output rotation shaft and a final output stage of a speed reducer fixed to the torque transmission shaft and connected to the electric motor are pressure-contacted via a friction portion. Possible main torque transmission plate, and a holding means for supporting the pressure contact force of the main torque transmission plate to the final output stage,
A means for bringing the main torque transmission plate into contact with the final output stage, and means for separating the main torque transmission plate from the final output stage,
The holding means is provided between the output rotation shaft and the torque transmission shaft with an engaging portion having an inclined surface that acts so as to increase the pressure contact force of the main torque transmission plate with respect to the final output stage with the torque transmission from the electric motor. It is a thing.

According to a third aspect of the present invention, there is provided a connecting main shaft having a pedal connecting shaft fixedly mounted on the pedal crank shaft and having a pedal connecting shaft fixed to the pedal crank, and a clutch mechanism is attached to the connecting main shaft. In the power assist machine for a bicycle, which transmits the torque of to the pedal crankshaft through the clutch mechanism and the connecting main shaft to assist the power,
The clutch mechanism is a torque transmission shaft that fits on the connecting main shaft,
A main torque transmission plate fixed to this torque transmission shaft and press-fitted to the final output stage of the reduction gear via a friction portion,
Holding means for supporting the pressure contact force of the main torque transmission plate to the final output stage, means for bringing the main torque transmission plate into contact with the final output stage, and means for separating the main torque transmission plate from the final output stage Is an interlocking main shaft and a torque transmission shaft provided with an engaging portion having an inclined surface that acts so as to increase the pressure contact force of the main torque transmission plate with respect to the final output stage with the torque transmission from the electric motor. is there.

According to a fourth aspect of the present invention, in the power assisting machine for a bicycle using the self-exciting clutch mechanism according to the third aspect, the connecting main shaft supports the pressure contact force from the main torque transmitting plate via the sliding member. Is.

According to a fifth aspect of the present invention, in the bicycle power assisting machine using the self-exciting clutch mechanism according to the third or fourth aspect, the means for bringing the main torque transmitting plate into contact with the final output stage is a torque from the speed reducer. A first rotating body that receives the rotation of the first rotating body and a coupling portion that projects due to the centrifugal force generated by the rotation of the first rotating body and transmits the rotation of the first rotating body to the main torque transmission plate. The main torque transmission plate is brought into contact with the final output stage by the rotation of the torque transmission plate.

According to a sixth aspect of the invention, in the power assisting machine for a bicycle using the self-exciting clutch mechanism according to the fifth aspect, the first rotating body is the drive rotation of the preceding stage for driving the final output stage of the reduction gear. It is rotationally driven by the driven rotary body of the preceding stage provided coaxially with the body, and the coupling portion is fixed to the central axis side of the first rotary body via the elastic body, and by the centrifugal force due to the rotation of the first rotary body. A weight plate provided with an engagement protrusion protruding from the peripheral surface of the first rotating body; and a second rotating body which is engaged with the engagement protrusion of the weight plate and rotates together with the first rotating body,
It is composed of a clutch shoe that is in frictional contact with the peripheral surface of the second rotating body and transmits the rotational force of the second rotating body to the main torque transmission plate.

According to a seventh aspect of the invention, in the bicycle power assist machine using the self-exciting clutch mechanism according to the third or fourth aspect, the means for bringing the main torque transmission plate into contact with the final output stage is the final stage of the speed reducer. A frame fixed to the side of the main torque transmission plate of the output stage and a spring member fixed to this frame, and the main torque transmission plate is projected to the outer peripheral side of this final output stage by the centrifugal force generated by the rotation of the final output stage. A weight member to be engaged with the main torque transmission plate is brought into contact with the final output stage by rotation of the main torque transmission plate.

The invention according to claim 8 is the invention according to claim 3, 4,
In the bicycle power assisting machine using the self-exciting clutch mechanism described in 5, 6, or 7, the means for separating the main torque transmission plate from the final output stage uses a spring force to separate the main torque transmission plate from the final output stage. Is.

According to a ninth aspect of the present invention, there is provided a connecting main shaft having a pedal connecting shaft fixedly mounted on the pedal crank shaft and having a pedal connecting shaft fixed to the pedal crank, and a clutch mechanism attached to the connecting main shaft. In the power assist machine for a bicycle, which transmits the torque of to the pedal crankshaft through the clutch mechanism and the connecting main shaft to assist the power,
The clutch mechanism is a torque transmission shaft that fits on the connecting main shaft,
The main torque transmission plate fixed to this torque transmission shaft, provided with a friction material on the outer peripheral part, and press-fitted to the final output stage gear of the reduction gear via the friction material, and the outer peripheral surface of the connected main shaft and the torque transmission A screw-shaped inclined surface that engages with each other is formed on the inner peripheral surface of the shaft, and the main torque transmission plate is moved in the thrust direction along the inclined surface due to the rotation of the main torque transmission plate. An engaging portion that increases the pressure contact force, and a first rotating body that receives the torque from the speed reducer and is rotationally driven.
A weight plate fixed to the central axis side of the first rotating body by a spring, and provided with an engaging projection protruding from the peripheral surface of the first rotating body by a centrifugal force generated by the rotation of the first rotating body; The second rotating body, which is engaged with the engaging projection of the weight plate and rotates together with the first rotating body, comes into frictional contact with the peripheral surface of the second rotating body, and the rotational force of the second rotating body is applied. A clutch shoe that transmits to the main torque transmission plate and a spring member that is attached to the main torque transmission plate and separates the main torque transmission plate from the final output stage when the electric motor stops rotating are provided.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. It should be noted that the pedal crank shafts of general-purpose bicycles are standardized into two types: a square cut shaft with a screw boss, and a shaft with a chrysanthemum groove with a screw hole at the center for mounting the pedal crank. A chain wheel is attached to the right side of the vehicle body, but there is a space on the left side. Furthermore, there is a space between the chain wheel and the front wheels. From this point of view, in each of the embodiments, the power assisting device of the present invention is mounted using the space of the general-purpose bicycle.

(First Embodiment) FIG. 1 is a perspective view showing the overall structure of a bicycle, and 1 is a body frame. The body frame 1 includes a head pipe 2, a top tube 3 extending rearward from the head pipe 2, a seat tube 4 extending from the top tube 3 to a bottom bracket (not shown), and the head pipe 2 Down tube 5 extending from the bottom bracket to the bottom bracket, a pair of left and right rear stays (not shown) extending rearward from the bottom bracket, and a pair of left and right seat stays 6 connecting the upper end of the seat tube 4 and the rear end of the rear stay. It consists of and.

A front fork 7 and a handle bar 8 are held on the head pipe 2 so as to be rotatable left and right, a front wheel 9 is rotatably attached to the front fork 7, and a handle 10 is fixed to the handle bar 8. Rear wheel 1 at the rear end of the rear stay
1 is rotatably attached. A saddle 12 is attached to the upper end of the seat tube 4 so as to be vertically movable. A chain wheel (not shown) is attached to the right side of the bottom bracket portion, and the chain wheel is covered with a chain wheel cover 13. The right pedal crank 14a is provided outside the chain wheel cover 13.
And a pedal 15a are provided. A gear case 16 is attached to the left side of the bottom bracket portion, and an electric motor 17 is fixed to the inner surface of the gear case 16 on the tip side.
A battery case 18, which is a power source, is detachably attached to the chain wheel cover 13. A left pedal crank 14b and a pedal 15b are provided outside the gear case 16.

FIG. 2 is a view of the bicycle as viewed from above with the body frame 1 omitted, showing the arrangement of the gear case 16 and the battery case 18. A plurality of batteries, for example, three 12 V sealed lead acid batteries are connected in series and housed in the battery case 18, and driving power is supplied from each of the batteries to the electric motor 17.

As shown in FIG. 3, the gear case 16 includes a plurality of reduction gears 22 including a final output stage gear 21 ,.
The speed reducer 23 consisting of is housed. The reduction gear 22
Is a ball bearing 2 mounted on a shaft 24 fixed in the case 16.
It is attached rotatably by 5.

As shown in FIG. 4, a connecting main shaft 26, which is an output rotary shaft, and a torque transmitting shaft 28, which is integrally fixed with a main torque transmitting plate 27, are connected through a central hole 21a of the final output stage gear 21. The screw-shaped inclined surface 26a formed on a part of the outer peripheral surface of the main shaft 26 and the screw-shaped inclined surface 28a formed on a part of the inner peripheral surface of the torque transmission shaft 28 are fitted and engaged with each other in this state. Pedal crankshaft 30 rotatably mounted on the bottom bracket 29 of the bicycle
The connecting main shaft 26 is attached to and fixed by a tightening nut 31. The screw-shaped inclined surface 26a and the screw-shaped inclined surface 28a constitute an engaging portion.

A pedal connecting shaft 32 is screwed to the connecting main shaft 26, and the pedal crank 14b having the left pedal 15b attached to the pedal connecting shaft 32 is tightened with a nut 33.
Fixed by. A cap 34 is screwed onto the pedal crank 14b so that the tightening nut 33 is not exposed to the outside. A bearing 35 made of a sliding material is attached to the inner peripheral portion of the final output stage gear 21 forming the center hole 21a, and the torque transmission shaft 28 for the coupling main shaft 26 is attached.
Can be engaged smoothly.

The final output stage gear 21 meshes with the pinion gear 36 which is the driving rotary body of the preceding stage, and the reduction gear 2 of the preceding stage which is a driven rotary body provided coaxially with the pinion gear 36.
Secondly, a clutch gear 37, which is a first rotating body, is rotatably fitted to the outer peripheral surface of a cylindrical portion 28b of which the screw-shaped inclined surface 28a of the torque transmission shaft 28 is provided on the inner peripheral surface.

As shown in FIG. 7, the clutch gear 37 has a cylindrical portion 37a formed at the center thereof and a circular protrusion 37b partially cut out near the outer peripheral portion of the cylindrical portion 37a. Further, the gear portion 37c is formed on the outer peripheral portion, and the weight is semicircular as shown in FIG. 5 between the outer periphery of the cylindrical portion 37a and the inner periphery of the protruding portion 37b, and the central portion is cut out in a semicircular shape. A plate 38 is provided. The weight plate 38 has an engaging protrusion 38a formed at the center of the outer periphery of the semicircular portion, and coil springs 39 are attached to both ends of the semicircular portion.
The central portion of the coil spring 39 is fixed between the outer circumference of the cylindrical portion 37a and the inner circumference of the protruding portion 37b and on the opposite side of the notch 37d of the protruding portion 37b. Then, the engaging projection 38a of the weight plate 38 is provided with the notch 3 of the projecting portion 37b.
7d, the weight plate 38 is usually a coil spring 39
The semicircular notch 38b is pulled by the inner peripheral portion of the cylindrical portion 3
7a, the tip of the engaging projection 38a is inside the outer peripheral surface of the projecting portion 37b in this state, and when the clutch gear 37 rotates, centrifugal force acts against the spring force of the coil spring 39 and the weight plate. 38 slides outward, and the tip of the engaging projection 38a projects outside the outer peripheral surface of the projecting portion 37b.

A driven ring 40, which is a second rotating body, is fitted on the outer periphery of the protrusion 37b of the clutch gear 37. The driven ring 40 has protrusions 40a and 40b formed on both sides of the outer peripheral edge, respectively, and a plurality of notches 40c having a predetermined width formed at predetermined intervals on one of the protrusions 40a. Projection 37b of clutch gear 37
It is designed to fit on the outer circumference of the.

The main torque transmission plate 27 fixes a first spring member 27a curved to one side so that both ends of the first spring member 27a come into contact with the end surface of the final output stage gear 21. A separation button 41 is attached. In addition, the main torque transmission plate 27 has a brake member 42 that has a curved outer peripheral portion.
The outer surface of the brake material 42 is partially inclined 42
When the main torque transmission plate 27 comes into contact with the final output stage gear 21, the inclined surface 42a comes into pressure contact with the tapered surface 21b formed on the final output stage gear 21.

The main torque transmission plate 27 also fixes the curved second spring member 27b shown in FIG. 6, and the clutch shoes 43 shown in FIG. 9 are provided at both ends of the second spring member 27b.
The arcuate surface 43a of the clutch shoe 43 is pressed against the outer peripheral surface of the driven ring 40.

The main torque transmission plate 27 and the torque transmission shaft 2
8, screw-shaped slope 26 formed on the outer peripheral surface of the connecting main shaft 26
a and an engaging portion composed of a screw-shaped inclined surface 28a formed on the inner peripheral surface of the torque transmission shaft 28, the clutch gear 37, the weight plate 38, the driven ring 40, the first spring member 27a, the separation button 41, and the second button. The mechanical portion configured by the spring member 27b, the brake material 42, and the clutch shoe 43 constitutes a self-excited clutch mechanism.

This self-excited clutch mechanism is designed to perform the following operations. That is, the electric motor 17
When each of the reduction gears 21 and 22 of the reduction gear 23 is rotated by the operation described above, the clutch gear 37 first rotates, and this engagement force causes the engagement protrusion 38a of the weight plate 38 to move from the notch 37d of the protrusion 37b of the clutch gear 37. The driven ring 40 is rotated integrally with the clutch gear 37 by projecting outward from the outer peripheral surface of the projecting portion 37 b and engaging the notch 40 c of the driven ring 40 with the tip of the engaging projection 38 a. When the driven ring 40 rotates, the main torque transmission plate 27 and the torque transmission shaft 28 rotate due to the friction of the clutch shoe 43 that is in pressure contact with the outer peripheral surface of the driven ring 40. When the torque transmission shaft 28 rotates, the screw-shaped sloped surface 28a formed on the inner peripheral surface of the torque transmission shaft 28 enters the screw-shaped sloped surface 26a formed on the outer peripheral surface of the coupling main shaft 26, and the brake material of the main torque transmission plate 27 is inserted. 22 is pressed against the taper surface 21b of the final output stage gear 21, whereby the screw-shaped sloped surface 28a formed on the inner peripheral surface of the torque transmission shaft 28 is attached to the screw-shaped sloped surface 26a formed on the outer peripheral surface of the coupling main shaft 26. The pressure contact force between the main torque transmission plate 27 and the final output stage gear 21 is strongly increased. Then, the main torque transmission plate 27 and the final output stage gear 21
The slippage between the main torque transmitting plate 27 and the main torque transmitting plate 27 eventually rotates together with the final output stage gear 21. In this way, the rotational torque from the final output stage gear 21 is transmitted to the connecting main shaft 26 via the main torque transmitting plate 27 and the torque transmitting shaft 28, and is further transmitted to the pedal crankshaft 30 of the bicycle.

When the operation of the electric motor 17 is stopped, the rotation of the reduction gears 21 and 22 of the speed reducer 23 is stopped, and the screw-shaped slope 26 formed on the outer peripheral surface of the connecting main shaft 26.
Rotation acts in a direction in which the screw-shaped inclined surface 28a formed on the inner peripheral surface of the torque transmission shaft 28 is disengaged from a. Further, the rotation of the clutch gear 37 is stopped, whereby the centrifugal force is lost, the engaging protrusion 38a of the weight plate 38 is retracted, and the rotation of the driven ring 40 is stopped. In addition, the first spring member 2
The main torque transmission plate 27 acts so as to be separated from the final output stage gear 21 by the separation means composed of 7a and the separation button 41. Thus, from the final output stage gear 21 to the main torque transmission plate 2
7 is separated, and the transmission of the rotational torque to the connecting main shaft 26 via the main torque transmitting plate 27 and the torque transmitting shaft 28 is stopped.

In a bicycle, the person pedals 15
It is necessary to operate this power assisting machine by rowing a and 15b. This is to detect the rotational speed, direction, acceleration and inclination angle of the pedals 15a and 15b, and to drive the electric motor 17.
It can be realized by controlling the operation start and operation stop of. In this case, the rotational torque from the electric motor 17, which is the auxiliary power, is detected and controlled by detecting the acceleration and inclination of the bicycle, and is set so as not to exceed human power.

For this control, Japanese Patent Application No. 7-70087 and Japanese Patent Application No. 7-700, which the present inventor has previously proposed and applied for, are used.
The technique described in No. 88 can be used. For example, the rotation speed of the pedal crank 14 b is determined by the stopper ring 44 that rotates integrally with the pedal crank shaft 30 and the rotation detecting concave-convex plate 4.
5, a multi-pole magnetized magnet is adhered and fixed to the outer peripheral portion of the uneven plate 45, and the uneven plate 45 is rotated by the rotation of the pedal crank shaft 30 accompanying the rotation of the pedal crank 14b. It can be detected by detecting a change in the magnetic pole of the magnet with a sensor including a Hall element. For acceleration of the bicycle, for example, a steel ball is rockably enclosed in a case having an inclined bottom surface, and the steel ball moves in a direction in which the steel ball moves up the inclined surface of the inclined bottom surface according to the acceleration of the bicycle. It can be detected by detecting with the photo sensor to which position the hill goes up.

In the power assist device having such a structure, the left pedal crank 14b of the existing bicycle is removed, and the connecting main shaft 26 in the gear case 16 in which the electric motor 17 having the self-excited clutch mechanism is mounted is attached to the pedal crank. It is fixed to the shaft 30. Then, the pedal connecting shaft 32 is screwed to the connecting main shaft 26, and the left pedal crank 14b is further attached.
Is fixed to the pedal connecting shaft 32 with a tightening nut 33. In this way, the power assist device incorporating the self-exciting clutch mechanism can be easily attached to an existing bicycle.

The main torque transmission plate 27 is separated from the final output stage gear 21 and the driven ring 40 is free with respect to the clutch gear 37 in a state before the operation of the bicycle in which the pedal is not depressed. . When the pedals 15a and 15b are depressed in this state to start the operation of the bicycle, the pedal connecting shaft 32, the connecting main shaft 26, the pedal crank shaft 30, and the pedal crank shaft 30 are rotated by the rotation of the pedal cranks 14a and 14b.
The stopper ring 44 rotates. The rotation speed of the pedal crank 14b is detected by the sensor based on the rotation of the stopper ring 44. In addition, the rotation of the pedal crank shaft 27
The bicycle moves forward and the acceleration of the bicycle is detected. When the rotation speed is equal to or higher than a fixed value and the acceleration is equal to or higher than a fixed value, a motor drive signal is generated and the electric motor 17 is activated.

When the electric motor 17 is started, the rotational torque of the electric motor 17 is transmitted to the reduction gear 23, and the reduction gear 22 and the final gear 21 rotate. The rotation of the reduction gear 22 causes the clutch gear 37 to rotate, and the centrifugal force causes the engagement protrusion 38a of the weight plate 38 to project outward and engage with the driven ring 40, so that the driven ring 40 rotates integrally with the clutch gear 37. To do. When the driven ring 40 rotates, the friction of the clutch shoe 43 causes the main torque transmission plate 27 and the torque transmission shaft 28 to rotate.

When the torque transmission shaft 28 rotates, the threaded sloped surface 28a of the torque transmission shaft 28 enters the threaded sloped surface 26a of the connecting main shaft 26, and the brake material 22 of the main torque transmission plate 27 moves to the final output stage gear 21. Tapered surface 21b
Press against. In this way, the pressure contact force between the main torque transmission plate 27 and the final output stage gear 21 increases, and eventually the main torque transmission plate 27 rotates together with the final output stage gear 21, so that the torque from the electric motor 17 is reduced. It is transmitted to the pedal crankshaft 27 via 23, and power assistance is performed.

In this way, even if the pedal torque due to human power is small, the power assist is performed by the torque from the electric motor 17, whereby the pedal crankshaft 27 obtains a sufficient rotational torque to move the bicycle. In this way, torque assistance proportional to the pedal driving power by human power can be easily realized.

When the pedaling is stopped or the pedal is reversely rotated, the operation of the electric motor 17 is immediately stopped and the reduction gear 22 of the reduction gear 23 and the final output stage gear 21 are stopped.
Rotation of the connecting spindle 26 is stopped,
6a, rotation acts in a direction in which the screw-shaped inclined surface 28a of the torque transmission shaft 28 is disengaged, and the rotation of the clutch gear 37 is stopped.
The engaging projection 38a of No. 8 retracts, and the rotation of the driven ring 40 stops. Further, the first spring member 27a and the separation button 4
The main torque transmission plate 27 acts so as to be separated from the final output stage gear 21 by the separating means composed of 1.

In this way, the transmission of the rotational torque from the final output stage gear 21 to the connecting main shaft 26 via the main torque transmitting plate 27 and the torque transmitting shaft 28 is smoothly stopped, so that the pedal can be stopped at an arbitrary position without any discomfort. In addition, the pedal can be smoothly rotated in the reverse direction without impairing the original feeling of the bicycle.

Further, the threaded slope 26a of the connecting main shaft 26
The screw-shaped sloped surface 28a of the torque transmission shaft 28 is inserted in and the brake material 22 of the main torque transmission plate 27 is brought into pressure contact with the tapered surface 21b of the final output stage gear 21, whereby the main torque transmission plate 27 and the final output stage gear 21 are Since the pressure contact force with the main torque transmission plate 2 is increased from the final output stage gear 21.
7. Rotational torque can be efficiently transmitted to the connection main shaft 26 via the torque transmission shaft 28, and therefore, even if a small and lightweight electric motor 17 is used, sufficient power assistance can be achieved.

Further, the clutch gear 37 is engaged with the preceding reduction gear 22 having a rotational speed three times or more that of the final output stage gear 21, and the weight plate 3 is engaged with this clutch gear 37.
Since 8 is attached, the centrifugal force of 9 times or more can be obtained as compared with the case where the weight plate 38 is directly attached to the final output stage gear 21, so that the weight plate 38 can be made compact and lightweight and the response of the clutch mechanism can be achieved. It is possible to improve the property.
For example, the rotation speed at which the clutch mechanism starts to be engaged is set to 750.
When the weight plate 38 has a mass of 10 gr and a rotation speed of about 0 rpm, a centrifugal force of about 20 gr may be applied. To obtain such an appropriate centrifugal force, a clutch gear having a diameter of 80 to 100 mm may be used. The clutch mechanism can be smoothly connected by sliding the weight plate 38 with an appropriate centrifugal force.

Also, by using a universal motor having a torque drooping characteristic as the electric motor 17, smooth torque assist can be performed without electric control means even when the bicycle is started, and the power can be increased as the vehicle speeds up. The auxiliary torque can be reduced. Further, the start time of the clutch operation due to the centrifugal force is shortened, and the response speed for performing appropriate power assistance is accelerated.

(Second Embodiment) In this embodiment, description will be made on the main structure including a self-excited clutch mechanism.
The same parts as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 10, the final output stage gear 21
The clutch frame 51 is fixed to one side of the outer edge of the clutch frame 51, and the leaf spring 52, which is a spring member, is fixed to the rear end of the clutch frame 51.
3 is fixed. That is, as shown in FIG. 11, one end of the clutch frame 51 is fixed to one side of the outer edge portion of the final output stage gear 21 with a screw 54, and the L-shaped leaf spring 52 is attached to the rear end of the clutch frame 51. One end of the weight spring 53 is fixed with a screw 55, and a weight member 53 is fixed to the other end of the leaf spring 52. The weight members 53 are projected to the left and right of the clutch frame 51 located on both sides of the weight member 53. When the final output stage gear 21 rotates in the direction of the arrow, the weight member 53 projects in the direction of the arrow against the spring force of the leaf spring 52 due to the centrifugal force thereof. The tip portion of the member 53 contacts the brake member 42 fixed to the outer peripheral portion of the main torque transmission plate 27, whereby the main torque transmission plate 27 and the torque transmission shaft 28 rotate. , The threaded sloped surface 28a of the torque transmission shaft 28 enters the threaded sloped surface 26a of the connecting main shaft 26, and the brake material 22 of the main torque transmission plate 27 presses against the tapered surface 21b of the final output stage gear 21 to transfer the main torque. The pressure contact force between the plate 27 and the final output stage gear 21 is increased.

Even in this case, the power assisting machine incorporating the self-exciting clutch mechanism can be easily attached to the existing bicycle, and the torque assisting proportional to the pedal driving power by human power can be easily realized. Further, the pedal can be stopped at an arbitrary position without any discomfort, and even if a small and lightweight electric motor is used, sufficient power assistance can be obtained, and the same operational effects as those of the first embodiment can be obtained. . However, since the rotation speed of the final output stage gear 21 is low, it is necessary to take measures such as making the weight member 53 heavy and increasing the diameter of the final output stage gear 21.

(Third Embodiment) In this embodiment, description will be made of a main part structure including a self-excited clutch mechanism,
The same parts as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 12, a stepping motor 61 is provided separately from the electric motor 17, a pinion gear 62 is attached to the rotary shaft of the stepping motor 61, and a gear portion formed on the outer circumference of the press contact ring 63 is attached to the pinion gear 62. And a screw for moving the press contact ring 63 forward and backward in the axial direction is formed on the inner peripheral portion of the press contact ring 63, and this screw is engaged with the screw formed on the gear case 16.

In this structure, the pinion gear 62 is rotated by rotating the stepping motor 61 forward or backward.
Is normally or reversely rotated, whereby the pressure contact ring 63 is normally or reversely rotated. When the pressure contact ring 63 rotates forward, the pressure contact ring 63 is moved to the main torque transmission plate 2
7 side, and the main torque transmission plate 27 by the press contact ring 63.
And press the main torque transmission plate 27 to the final output stage gear 2
1 is pressed. When the pressure contact ring 63 rotates in the reverse direction, the pressure contact ring 63 is retracted from the main torque transmission plate 27 side to release the pressing of the main torque transmission plate 27 by the pressure contact ring 63, and the main torque transmission plate 27 is spring-loaded. Member 27
It is separated from the final output stage gear 21 by a separating means composed of a and a separation button 41.

As described above, the main torque transmission plate 27 can be brought into pressure contact with or separated from the final output stage gear 21 by moving the pressure contact ring 63 forward or backward using the stepping motor 61. That is, the clutch mechanism can be connected and disconnected.

In addition, instead of the stepping motor 61, it is possible to press the main torque transmission plate 27 to the final output stage gear 21 or separate it from the main torque transmission plate 27 by using an electromagnetic solenoid.

Also in this embodiment, the power assist device can be easily attached to the existing bicycle, and the torque assist proportional to the pedal driving power by the human power can be easily realized, and the pedal can be placed at any position. The same operational effect as that of the first embodiment can be obtained in that it can be stopped without a feeling of discomfort, and that even if a small and lightweight electric motor is used, power assistance can be sufficiently performed.

[0051]

As described above, according to the first and second aspects of the present invention, the rotational torque of the electric motor is transmitted to the main torque transmission plate, and the main torque transmission plate is pressed against the final output stage of the speed reducer. The torque of the electric motor can be reliably transmitted to the output rotary shaft by self-excitation.

Further, according to the inventions of claims 3 to 9, it can be easily attached to a commercially available ordinary bicycle, the versatility can be improved, and the torque of the electric motor can be reliably transmitted to the petal crankshaft. It is possible to provide appropriate power assistance proportional to the pedal drive power by human power. In addition, the pedal can be smoothly rotated in the reverse direction, which does not impair the feeling of a bicycle. Further, it is possible to reduce the size and weight of the electric motor.

[Brief description of drawings]

FIG. 1 is a perspective view of a bicycle showing a first embodiment of the present invention.

FIG. 2 is a plan view of the bicycle according to the first embodiment viewed from above with the body frame omitted.

FIG. 3 is a partial cross-sectional plan view showing the main configuration of the same embodiment.

FIG. 4 is an exploded perspective view showing a coupled main shaft, a main torque transmission plate, and a final output stage gear in the same embodiment.

5A and 5B are diagrams showing a configuration of a weight plate in the same embodiment, where FIG. 5A is a side view and FIG. 5B is a plan view.

FIG. 6 is a diagram showing a configuration of a first spring member in the same embodiment.

7A and 7B are diagrams showing a configuration of a final output stage gear in the same embodiment, where FIG. 7A is a plan view and FIG. 7B is a sectional view taken along line AA of FIG.

8A and 8B are views showing a configuration of a driven ring in the same embodiment, in which FIG. 8A is a plan view and FIG. 8B is a sectional view taken along line BB of FIG. 8A.

9A and 9B are views showing the configuration of the clutch shoe in the same embodiment, where FIG. 9A is a plan view and FIG. 9B is a sectional view taken along line CC of FIG. 9A.

FIG. 10 is a partial cross-sectional plan view showing the configuration of the main part of the second embodiment of the present invention.

FIG. 11 is a view showing a configuration of a weight member mounting portion in the same embodiment, (a) is a partially enlarged view seen from one side,
(b) is a partially enlarged view from the other side.

FIG. 12 is a partial cross-sectional plan view showing the configuration of the main part of the third embodiment of the present invention.

[Explanation of symbols]

 14a, 14b ... Pedal crank 17 ... Electric motor 21 ... Final output stage gear 22 ... Reduction gear 23 ... Reduction gear 26 ... Connection main shaft 27 ... Main torque transmission plate 28 ... Torque transmission shaft 30 ... Pedal crank shafts 26a, 28a ... Threaded Slope 32 ... Pedal connecting shaft 37 ... Clutch gear 38 ... Weight plate 40 ... Follower ring 41 ... Separation button 42 ... Brake material 43 ... Clutch shoe

Claims (9)

[Claims] 1. The rotation of an electric motor causes a final output stage of a speed reducer connected to the electric motor to rotate, and a main torque transmission plate is brought into frictional contact with the final output stage to rotate. Due to the rotation, the engagement state of the engagement portion provided between the torque transmission shaft fixed to the main torque transmission plate and the output rotation shaft is strengthened, and the pressure contact force of the main torque transmission plate to the final output stage is increased. A self-excited clutch mechanism, wherein torque of the electric motor is transmitted to the output rotary shaft. 2. A torque transmission shaft fitted to the output rotation shaft,
A main torque transmission plate fixed to this torque transmission shaft and capable of pressure contact with the final output stage of the speed reducer connected to the electric motor via a friction portion, and a pressure contact force of the main torque transmission plate to the final output stage. And a means for bringing the main torque transmission plate into contact with the final output stage, and a means for separating the main torque transmission plate from the final output stage,
The holding means has, between the output rotation shaft and the torque transmission shaft, an inclined surface that acts so as to increase the pressure contact force of the main torque transmission plate with respect to the final output stage in accordance with the torque transmission from the electric motor. A self-exciting clutch mechanism, characterized in that an engaging portion is provided. 3. A connecting main shaft having a pedal connecting shaft fixedly mounted on the pedal crank shaft and having a pedal crank fixed thereto is provided, and a clutch mechanism is attached to the connecting main shaft.
A bicycle power assisting machine for assisting power by transmitting torque from an electric motor with a multi-stage speed reducer to the pedal crankshaft via the clutch mechanism and a connecting main shaft, wherein the clutch mechanism is a torque transmitting unit that is fitted to the connecting main shaft. A shaft, a main torque transmission plate fixed to the torque transmission shaft and capable of pressure contact with the final output stage of the speed reducer via a friction portion, and a pressure contact force of the main torque transmission plate with respect to the final output stage. Holding means for supporting the main torque transmission plate, means for bringing the main torque transmission plate into contact with the final output stage, and means for separating the main torque transmission plate from the final output stage. An engagement portion having an inclined surface is provided between the transmission shaft and the transmission shaft so as to increase the pressure contact force of the main torque transmission plate with respect to the final output stage as the torque is transmitted from the electric motor. A power auxiliary machine for bicycles that uses a self-excited clutch mechanism. 4. The power auxiliary machine for a bicycle using a self-exciting clutch mechanism according to claim 3, wherein the connecting main shaft supports a pressure contact force from the main torque transmitting plate via a sliding member. 5. The first contact means for bringing the main torque transmission plate into contact with the final output stage receives torque from a speed reducer and is driven to rotate.
And a coupling portion for projecting the rotation of the first rotating body to the main torque transmitting plate by a centrifugal force generated by the rotation of the first rotating body, and the connecting portion for transmitting the rotation of the first rotating body to the main torque transmitting plate. The power assist device for a bicycle using a self-exciting clutch mechanism according to claim 3 or 4, wherein the main torque transmission plate is brought into contact with the final output stage. 6. The first rotating body is rotatably driven by a preceding driven rotating body provided coaxially with a preceding driving rotating body that drives a final output stage of the speed reducer, and the coupling portion is the first rotating body. A weight plate fixed to the central axis side of the body via an elastic body, and provided with an engagement protrusion protruding from the peripheral surface of the first rotating body by a centrifugal force generated by the rotation of the first rotating body, and this weight. The second rotating body, which is engaged with the engaging protrusion of the plate and rotates together with the first rotating body, comes into frictional contact with the peripheral surface of the second rotating body, and the rotational force of the second rotating body is applied. The power auxiliary machine for a bicycle using a self-excited clutch mechanism according to claim 5, characterized in that it comprises a clutch shoe for transmitting to the main torque transmitting plate. 7. The means for bringing the main torque transmission plate into contact with the final output stage includes a frame fixed to the side of the final output stage of the reduction gear on the side of the main torque transmission plate, and a frame member fixed to this frame via a spring member. A weight member protruding toward the outer peripheral side of the final output stage by the centrifugal force generated by the rotation of the final output stage to engage with the main torque transmission plate, and the main torque transmission plate is finally rotated by the rotation of the main torque transmission plate. The bicycle power auxiliary machine using the self-exciting clutch mechanism according to claim 3 or 4, wherein the bicycle power auxiliary machine is brought into contact with the output stage. 8. The means for separating the main torque transmission plate from the final output stage is characterized in that the main torque transmission plate is separated from the final output stage by a spring force.
Alternatively, a power auxiliary machine for a bicycle using the self-exciting clutch mechanism described in 7. 9. A connecting main shaft having a pedal connecting shaft fixedly mounted on the pedal crank shaft and having a pedal crank fixed thereto is provided, and a clutch mechanism is attached to the connecting main shaft.
A bicycle power assisting machine for assisting power by transmitting torque from an electric motor with a multi-stage speed reducer to the pedal crankshaft via the clutch mechanism and a connecting main shaft, wherein the clutch mechanism is a torque transmitting unit that is fitted to the connecting main shaft. A shaft, a main torque transmission plate fixed to the torque transmission shaft, provided with a friction material on the outer periphery thereof, and press-fitted to the final output stage gear of the reduction gear via the friction material, and the connected main shaft A screw-shaped slanted surface is formed on the outer peripheral surface of the main shaft and the inner peripheral surface of the torque transmission shaft, and the main torque transmission plate is moved in the thrust direction along the slanted surface by the rotation of the main torque transmission plate. An engaging portion that increases the pressure contact force of the main torque transmission plate with respect to the stepped gear, a first rotating body that receives torque from the speed reducer, and is rotationally driven, and a spring on the central axis side of the first rotating body. The weight plate, which is fixed and provided with an engaging projection protruding from the peripheral surface of the first rotating body by the centrifugal force generated by the rotation of the first rotating body, is engaged with the engaging projection of the weight plate, A second rotating body that rotates together with the first rotating body; a clutch shoe that makes frictional contact with the peripheral surface of the second rotating body and transmits the rotational force of the second rotating body to the main torque transmission plate; A power assisting machine for a bicycle using a self-exciting clutch mechanism, which is mounted on the main torque transmission plate, and is provided with a spring member for separating the main torque transmission plate from the final output stage when the rotation of the electric motor is stopped. .