JP2002012180A - Front wheel drive assist bicycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a front wheel drive assist bicycle for surely stopping motor driving force of a front wheel when applying a brake to the front wheel or a rear wheel. SOLUTION: A board-like casing 20 with a built-in motor M is arranged in a part of a rotary shaft 10 in a hub of the front wheel 5 of a front wheel drive assist bicycle body. A manually driving part has a pedal 7, a crank 8 and a chain 9, and when a user steps on the pedal 7, the crank 8 rotates, and rotates the rear wheel 6 via the chain 9. Brake levers 13 and 13 are installed on the left and right both ends of a handlebar 12 for steering the front wheel 5, and brake devices 14 and 15 including a brake shoe are connected by a front brake wire 16 and a rear brake wire 17. Brake switches 18 and 18 are arranged in the middle of the front brake wire 16 and the rear brake wire 17, and the brake switches 18 and 18 operate when operating the brake levers 13 and 13, and become a mechanism for stopping current-carrying to the motor built in the board-like casing 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an assist bicycle for assisting human driving force with a motor driving force.

[0002]

2. Description of the Related Art Recently, both a human-powered drive unit and a motor-driven electric drive unit are provided, and a motor is driven in accordance with the magnitude of the manual drive force, and the human-powered drive force is assisted by the motor drive force. Electric bicycles, so-called assist bicycles, are gaining in popularity.

Conventionally, as such an electric bicycle, a so-called rear-wheel drive type electric assist bicycle, in which a rear wheel is directly rotated by a motor, as proposed by the present applicant, is known. In addition, Japanese Patent Application Laid-Open No. 7-329873 and Japanese Patent Application Laid-Open
As disclosed in JP-A-150981 and JP-A-8-207875, there is also known one in which a drive unit is provided on a front wheel.

[0004]

In a rear-wheel drive type electric assist bicycle, a person drives a rear wheel motor in accordance with a force to rotate the rear wheel. , Could brake both manpower and motor. However, in an assist bicycle that has a drive unit on the front wheel, the person drives the front wheel motor according to the force to rotate the rear wheel, so when the brake is applied to the rear wheel, the brake is applied to the rear wheel by human power. Although it can be applied, there is a problem that the brakes are not applied to the motor of the front wheels, resulting in a dangerous state. Therefore, an object of the present invention is to provide a front-wheel drive assist bicycle that has a drive unit on the front wheel, but reliably stops the motor driving force of the front wheel when a brake is applied to the front wheel or the rear wheel.

[0005]

According to a first aspect of the present invention, there is provided a front-wheel drive assisted bicycle for transmitting a manual drive force from a pedal to a rear wheel, and a front wheel portion. And an electric drive unit using a motor as a drive source, so that the assist operation to the front wheels is stopped when a brake operation is performed on the rear wheels.

A front-wheel drive assisted bicycle according to a second aspect of the present invention has a human-powered drive unit for transmitting human-powered drive from a pedal to rear wheels, and an electric drive unit using a motor as a drive source in the front wheel unit. When a brake is applied to the rear wheel, a switch for detecting the brake operation is provided in the middle of the brake wire,
The assist operation to the front wheels is stopped by the detection output of the switch.

A front-wheel drive assisted bicycle according to a third aspect of the present invention has a human-powered drive unit for transmitting human-powered drive from a pedal to rear wheels, and an electric drive unit using a motor as a drive source at the front wheel unit. When a brake is applied to the rear wheel, a switch composed of a reed switch for detecting the brake operation is provided in the middle of the brake wire, and the assist operation to the front wheel is stopped by a detection output of the switch.

According to a fourth aspect of the present invention, there is provided a front-wheel drive assisted bicycle having a human-powered drive unit for transmitting a human-powered drive from a pedal to rear wheels, and an electric drive unit using a motor as a drive source at the front wheel unit. When the rear wheel brake is operated, the assist operation to the front wheel is stopped, and a switch for detecting the front wheel brake operation is provided, and the output of the drive unit is stopped even when the front wheel switch is turned on. did.

Thus, the front-wheel drive assisted bicycle of the present invention can prevent the driving force of the motor M from being immediately released by the brake operation on the rear wheels including the front wheels, thereby preventing a dangerous state from occurring. As a result, the wear of the brake shoes can be suppressed without shortening the life of the motor. Since the braking distance of the electric bicycle is shorter than that of the conventional bicycle, operational safety can be ensured.

A front-wheel drive assisted bicycle according to a fifth aspect of the present invention has a human-powered drive unit for transmitting a manual drive force from a pedal to a rear wheel, and an electric drive unit using a motor as a drive source at the front wheel unit. When a brake is applied to the rear wheels, the assist operation to the front wheels is stopped, and a torque sensor for detecting the manual driving force is provided, and the driving force of the electric driving unit is controlled by the driving force according to the detected value of the torque sensor. It was configured to be.

A front-wheel drive assisted bicycle according to a sixth aspect of the present invention has a human-powered drive unit for transmitting a manual drive force from a pedal to a rear wheel, and an electric drive unit using a motor as a drive source in the front wheel unit. When a brake is applied to the rear wheel, the assist operation to the front wheel is stopped, and a torque sensor for detecting the manual driving force is provided on the sprocket, and the driving force of the electric driving unit is determined by the driving force corresponding to the detected value of the torque sensor. Is configured to be controlled.

A front-wheel drive assisted bicycle according to a seventh aspect of the present invention has a human-powered drive unit for transmitting a manual drive force from a pedal to a rear wheel, and an electric drive unit using a motor as a drive source in the front wheel unit. When a brake is applied to the rear wheel, the assist operation to the front wheel is stopped, and a torque sensor for detecting a manual driving force formed of an elastic body that expands and contracts according to the magnitude of the human power is provided. The driving force of the electric driving unit is controlled by the driving force.

Thus, the driving force of the electric drive unit is controlled by the driving force corresponding to the detection value of the torque sensor,
An elastic body that expands and contracts according to the level of human power is provided between the plate fixed to the crank linked to the pedal and the front sprocket, and a torque sensor can be attached around the plate. Assembly can be facilitated.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of an electric bicycle of a front-wheel direct drive type will be described below with reference to the drawings. FIG. 1 is an overall perspective view of a front-wheel direct drive type assisted bicycle. In the figure, the assisted bicycle main body is provided with a motor drive unit described later, and the drive of the motor drive unit is performed according to the magnitude of torque by human power. The power is changed, and the vehicle is driven by assisting human power with the power of the motor drive unit.

The main frame 1 of the front wheel drive assisted bicycle body includes a head pipe 2 and a saddle 4 provided at the front.
Is connected to a seat tube 3 provided below. A handle 12 and a front wheel 5 are attached to the head pipe 2. The front wheel 5 is composed of a spoke, a rim, and a tire. Is provided. Front wheel 5
Is steered by a steering wheel 12.
The rear wheel 6 is also made up of spokes, rims, and tires.
It is rotated by the driving force of the human power drive.

As shown in FIG. 2, the disk-shaped casing 20 includes a rotating casing 21 which rotates in conjunction with the front wheel 5.
And a fixed casing 22 fixed to the front wheel drive assist bicycle body.
2, a motor control circuit (42 in FIG. 6) is fixed internally.

Further, a stator 23 and a brush 25 of the motor are provided on a fixed casing 22 of the disc-shaped casing 20, and the whole is fixed to the axle 10. The rotor of the motor is fixed to the rotating casing 21 and the brush 2
The rotational force of the rotor 24, which is supplied with electric power from the motor 5 through the commutator 26, is transmitted through a reduction gear comprising a planetary gear unit.

As shown in FIGS. 3 and 4, the planetary gear device serving as a reduction gear is provided with an internal gear 2 in a rotating casing 21.
It is composed of seven and three planetary gears 28 and a sun gear around the axle 10, and the electric driving force transmitted to the rotating casing 21 drives the front wheels 5.

Fixed side casing 2 of board-shaped casing 20
2 is fixed to a fixing member by a screw, and the fixing member is screwed to a plate 29. The plate 29 is fixed to a bicycle frame so that the fixed casing 22 does not rotate due to a reaction force generated by a motor.

The human-powered drive unit includes a pedal 7, a crank 8, and a chain 9. When the user steps on the pedal 7, the crank 8 rotates, and the rear wheel 6 rotates via the chain 9. In this example, the chain is a transmission member of human power. However, the invention is not limited to this, and a chain, a belt, a rotating shaft or the like may be used instead of the chain.

Brake levers 13 and 13 are attached to both left and right ends of a steering wheel 12 for steering the front wheel 5, and brake devices 14 and 15 are provided for the front wheel 5 and the rear wheel 6, respectively. 13 and the brake devices 14 and 15 including the brake shoes,
It is connected by a rear brake wire 17. Also,
Brake switches 18, 18 are provided in the middle of the front brake wire 16 and the rear brake wire 17, and when the brake levers 13, 13 are operated, the brake switch 1
The motors 8 and 18 operate to stop the power supply to the motor built in the casing 20.

A seat tube 3 provided below the saddle 4 is provided with a battery unit 11 serving as a power supply for a motor. The battery section 11 includes a battery case slidably attached to and detachable from the seat tube 3 and a single rechargeable battery housed in the battery case. The power supply voltage is approximately 24 volts.

Reference numeral 19 denotes a front sprocket which rotates with the rotation of the pedal 7, and a chain 9 is hung on the front sprocket 19 so that the rotation of the front sprocket 19 is transmitted to the rear wheel 6.

Next, the structure of the front sprocket 19 will be described with reference to FIGS. Reference numeral 30 denotes two convex portions formed at positions opposite to the crankshaft of the crank 8. The convex portions 30 are formed on the side to which the front sprocket 19 is attached. Numeral 31 is a disk-shaped plate fixedly attached to the crank 8. The plate 31 rotates with the rotation of the crank 8 by receiving a manual driving force from the crank 8.

Reference numeral 32 denotes the plate 31
A first pin mounted in a direction perpendicular to the plane, the first pin 32 extending from the plate 31 and
7 and play are provided and penetrated. Reference numeral 33 denotes a second pin mounted on the front sprocket 19 in a direction perpendicular to the front sprocket 19, and the second pin 33 extends from the front sprocket 19 and penetrates the plate 31 with play provided. ing.

Numeral 34 denotes a ring-shaped elastic body made of metal and having a partially cut-out elasticity, that is, a washer spring. It is provided. Further, the washer spring 34 on the plate 31 side is fixed by a nut to one end of the first pin 32 fixed to the plate 31 and the other end to the second pin 33 fixed to the front sprocket 19.

The washer spring 34 fixed to the front sprocket 19 side has one end thereof.
The other end is fixed to the second pin 33 fixed to the first pin 32 fixed to the plate 31 by a nut. That is, the human-powered driving force transmitted by depressing the pedal 7 is transmitted from the crank 8 to the plate 31 and is transmitted to the front sprocket 19 by bending the washer spring 34. When the washer spring 34 is bent, the plate 31 A play is formed between the first pin 32 and the front sprocket 19 so that the rotation with the front sprocket 19 is shifted.

The reason why the play is formed between the second pin 33 and the plate 31 is that the same displacement as described above occurs. The washer spring 3
Numeral 4 is attached at a position where the center of the ring of the washer spring 34 and the crankshaft are eccentric.
2. The second pin 33 is arranged and attached at a position away from the crankshaft.

Further, the first pin 32 and the second pin 33 are arranged at a position having an angle of about 90 degrees with respect to the direction in which the crank 8 is provided, and the first pin 32, the second pin 33, and When attaching the washer spring 34 and the like, the crank 8 does not interfere.

Reference numeral 35 denotes a ring holder provided on the outer periphery of the crankshaft and movably attached along the crankshaft. The ring holder 35 has a chevron 36 which is in contact with the convex portion 30. When the part 30 rotates, the chevron 36 is pushed by the protrusion 30 and moves in the crankshaft direction.

The ring holder 35 is partially provided with an aluminum ring 37 which is a conductive material, and moves with the movement of the ring holder 35. Furthermore,
Two bosses 38 are formed on the ring holder 35, and the bosses 38 are inserted into the front sprocket 19 to form play with the plate 31 and pass therethrough. And
Springs 39 are provided between the boss 38 and the front sprocket 19, respectively, and the ring holder 35 is biased toward the crank 8.

Numeral 40 is a detecting means, that is, a coil formed with a diameter larger than that of the ring 37 and fixed to the main body frame 1 near the moving range of the ring 37. Then, a change in the inductance resulting from the operation is output as an electric signal to a control circuit of a motor fixed to the fixed casing 22 in the board-shaped casing 20. Here, the ring holder 35 and the coil 40 detect the bending of the washer spring 34 as a torque sensor.

Next, the operation of this embodiment will be described with respect to human driving force. The human-powered driving force obtained by pressing the pedal 7 rotates the crank 8 and simultaneously rotates the plate 31 with the rotation of the crank 8. When the plate 31 rotates, the driving force is transmitted from the first pin 32 side of the washer spring 34 to the second pin 33 side, and at this time, the driving force is transmitted to the front sprocket 19 while the washer spring 34 bends. A connecting band connected to the front sprocket 19 and the rear sprocket (not shown), that is, the chain 9
Drives the rear wheel 6.

Next, a description will be given of an electric driving force which is a driving portion of the front wheels. The washer spring 34 bent by the amount of the manpower torque generated by the manpower drive force causes the rotation of the plate 31 and the rotation of the front sprocket 19 to shift. At this time,
The protrusion 30 presses the chevron 36 by the amount of the displacement, and the ring holder 35 moves in the crankshaft direction.

When the ring holder 35 moves, the ring 37 also moves in the coil 40, and the magnitude of the manual torque is changed to the change in the inductance of the coil 40, and the ring 37 is fixed to the fixed side casing 22 in the board-shaped casing 20. Input to the motor control circuit. When no human torque is applied to the ring holder 35,
The urging force of the spring 39 returns to the original position.

The control circuit is programmed so that the magnitude of the input manual driving force and the magnitude of the electric driving force are the same. Is driven, and the front wheel 5 is rotated by the driving force of the motor. As described above, the rear wheel 6 is driven by the manual driving force, and the front wheel 5 is driven by the electric driving force having the same magnitude as the manual driving force.

As described above, the portion of the washer spring 34 attached by the first pin 32 is
Since the eccentricity is set in a direction away from the rotation center of the crank 8, the amount of bending with the same force is smaller than when the center of the washer spring 34 and the rotation center of the crank 8 are the same. The sheath strength can be reduced, and the washer spring 34 can be reduced in weight.

The plate 31 fixed to the crank 8
And the front sprocket 19, the washer spring 34 is provided, so that a torque sensor can be attached to the periphery of the plate 31 so that the configuration is simplified and the plate 31
Can be unitized, so that assembly is simplified. Further, in the above embodiment, an example in which a change in the inductance of the coil 40 is used has been described as the torque sensor, but it is needless to say that another known torque sensor may be used.

FIG. 6 shows an outline of a drive circuit for a front wheel assist motor according to the present invention. In the figure, an output from a battery power supply 11 is converted into a constant voltage by a constant voltage circuit 43 via a main switch 41 and supplied to a control circuit 42. Control circuit 4
2, a current detection circuit 46, a voltage detection circuit 47, an output of the brake switch 18, and an output of the torque sensor 48 are supplied. Based on these detection signals, a drive signal is output to the motor drive circuit 45 according to a predetermined program. The drive circuit 45 controls the energization of the assist motor M via the semiconductor element 49. Further, the control circuit 42 outputs a signal indicating the state of charge of the battery to the remaining battery level display circuit 44.

When a brake signal is output from the brake switch 18, the power supply to the motor is stopped, and the assist force to the front wheels is stopped. A switch 18 is provided on each of the front brake wire 16 and the rear brake wire 17. Since the mechanism of these two switches 18 is the same, the mechanism of the switch 18 provided on the rear brake wire 17 will be described below.

That is, as shown in detail in FIGS. 7 and 8, the switch 18 includes a box-shaped switch case 50 attached to the middle of the length of the rear brake wire 17;
A sleeve 51 attached to the inner wire 17 a of the rear brake wire 17 in the switch case 50, a magnet 52 attached to the upper surface of the sleeve 51, and attached to a circuit board 53 in the switch case so as to face the magnet 52. And a reed switch 54 provided. 17b is an outer tube of the rear brake wire 17.

The reed switch 54 is turned on when the magnet 52 is in the state shown in FIG. 8 or when the magnet 52 is moved leftward by the movement of the inner wire 17a from the state shown in FIG.
It turns off when it moves to the right and reaches the state shown in FIG. FIG. 10 is a circuit diagram showing an electric circuit in which the switch 18 is incorporated. In FIG. 10, reference numeral 41 denotes a main switch. Hereinafter, the operation of the switch 18 will be described with reference to FIG.

When the reed switch 54 is turned on with the main switch 41 turned on, the motor M is supplied with current from the battery 11 to rotate, and the front wheel 5 rotates in cooperation with the rotation of the rear wheel driven by human power. The electric bicycle runs with assist drive. At this time, the reed switch 54 and the magnet 52 of the switch 18 are in the state shown in FIG.

In this state, when the brake operation is performed by gripping the front brake lever 13 and the rear brake lever 13, the front brake wire 16 or the rear brake wire 17 is operated.
Of the inner wire 17a is pulled. Inner wire 1
The magnet 52 moves to the right by 7a, and the state shown in FIG. 9 is obtained. Then, the reed switch 54 is turned off, and the rotation of the motor stops. At this time, the rear brake shoe 1
5 is pressed against the rear wheel 6 to stop the rotation of the rear wheel 6, and the front brake shoe 14 is pressed against the front wheel 5 to stop the rotation of the front wheel 5.

As described above, the motor M based on the brake operation
Is stopped by operating the switch 18 attached to the front brake wire 16 or the rear brake wire 17 with the front and rear brake levers 13, 13.

Therefore, according to this electric bicycle, the driving force of the motor M is immediately released by the braking operation on the rear wheels including the front wheels, so that a dangerous state can be prevented. Since no load is applied, the wear of the brake shoes 14 and 15 can be suppressed without shortening the life of the motor. Further, since the braking distance of the electric bicycle is shorter than that of the conventional bicycle, operational safety is maintained. In addition, by using a waterproof sealed reed switch 54 and magnet 52, safety in waterproofing can be ensured.

In this electric bicycle, the switch 18
The reed switch 54 was used as the
As shown in FIG. 11 showing a switch ON state and FIG. 12 showing a switch OFF state, a micro switch 60 may be used. In addition, in both figures, reference numeral 61 denotes an operation piece attached to the inner wire 17a of the rear brake wire 17.

In another embodiment, the switches 18 and 18 attached to the front brake wire 16 and the rear brake wire 17 of the electric bicycle are put together to form the switch 5.
5 can be provided. The internal structure of the switch 55 is shown in FIGS.

The switch 55 is a box-shaped switch case for bundling the front brake wire 16 and the rear brake wire 17 in the middle of their length, and has an inner wire 16a of the front brake wire 16 and a rear brake wire 17 in the switch case. Sleeves 51, 51 attached to the inner wires 17a of the
Magnets 52, 52 attached to the upper surfaces of
And lead switches 54, 54 attached to the circuit boards 53, 53 in the switch case 50 so as to face the magnets 52, 52. In addition, 1
6b is an outer tube of the front brake wire 16.

The electric circuit of the switch 18 is configured so that the rotation of the motor M is stopped when at least one of the lead switches 54, 54 is turned off as shown in FIG. 12 (the electric circuit diagram is omitted).

Next, a control operation including a brake operation of the front wheel drive assist motor of the present invention will be described with reference to a control flow of FIG. Control is started in step S1.
When a brake operation is detected in step S2, it is determined in step S3 whether the brake switch is ON (Yes). If the brake switch is on, the process proceeds to step S7, where the motor is turned off to stop the driving force of the assist motor.

In step S3, the brake switch is turned off.
If it is determined as (No), in step S4,
An input, that is, a stepping force (torque) of a human pedal is detected, and it is determined in step S5 whether the input is larger than a predetermined value. That is, it is determined whether the foot is simply put on the pebble or whether it is driven manually.

If the input is smaller than the predetermined value (No), the process proceeds to step S7, where the motor is turned off and the driving force of the assist motor is stopped. If the input is larger than the predetermined value (Yes), the process proceeds to step S6, in which the assist motor is turned on, and the front wheel drive assist is controlled by the operation mode of the control circuit in FIG.

[0054]

As described above, in the front-wheel drive assisted bicycle of the present invention, the driving force of the motor M is immediately released by the braking operation on the rear wheels including the front wheels, so that a dangerous state can be prevented. Also, since no abnormal load is applied to the motor, without shortening the life of the motor,
Brake shoe wear can be reduced. And
Since the braking distance of the electric bicycle is shorter than that of the conventional bicycle, operational safety is also maintained. In addition, by using a waterproof sealed reed switch and a magnet, safety in waterproofing can be ensured.

Further, an elastic body that expands and contracts according to the magnitude of human power is provided between the plate fixed to the crank linked to the pedal and the front sprocket, and a torque sensor can be attached to the periphery of the plate. Since the plate portion can be unitized, assembly becomes easy.

[Brief description of the drawings]

FIG. 1 is an overall view of a front wheel drive assisted bicycle according to the present invention.

FIG. 2 is a sectional view of a board-shaped casing.

FIG. 3 is a layout diagram of a planetary gear device.

FIG. 4 is a front view of a front sprocket.

FIG. 5 is a side view of the front sprocket.

FIG. 6 is a drive control circuit of an assist motor.

FIG. 7 is an internal configuration diagram of a switch.

FIG. 8 is a cross-sectional view when a switch is in an ON state.

FIG. 9 is a cross-sectional view when the switch is in an OFF state.

FIG. 10 is a control circuit diagram of a switch and a brake.

FIG. 11 is a cross-sectional view when the microswitch is in an ON state.

FIG. 12 is a cross-sectional view of the microswitch in an OFF state.

FIG. 13 is an internal configuration diagram of another switch.

FIG. 14 is a cross-sectional view when another switch is in an ON state.

FIG. 15 is a cross-sectional view when another switch is in an OFF state.

FIG. 16 is a control flow including a brake operation of the front wheel drive assist motor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main frame 4 Saddle 5 Front wheel 6 Rear wheel 7 Pedal 8 Crank 9 Chain 10 Axle 11 Battery part 12 Handle 13 Brake lever 14, 15 Brake device 16, 17 Brake wire 18 Brake switch 19 Front sprocket 20 Disc casing 21 Rotating casing 22 Fixed casing 23 Motor stator 24 Motor rotor 25 Brush 26 Commutator 27 Internal gear 28 Planetary gear 31 Disc-shaped plate 34 Ring-shaped elastic body 40 Coil 41 Main switch 42 Control circuit 44 Battery remaining amount display circuit 45 Drive Circuit 50 Switch case 52 Magnet 54 Reed switch 60 Micro switch

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Hiroaki Sagara 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Toshihiro Matsumoto 2-chome, Keihanhondori, Moriguchi-shi, Osaka No. 5 Sanyo Electric Co., Ltd. (72) Inventor Seiki Inui 2-5-5 Keihan Hondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd.

Claims (7)

[Claims] 1. A human-powered drive unit for transmitting a manual drive force from a pedal to a rear wheel, and an electric drive unit using a motor as a drive source in a front wheel unit, and assisting the front wheel when braking the rear wheel. A front-wheel drive assisted bicycle characterized in that it stops operating. 2. The front wheel drive assisted bicycle according to claim 1, wherein the switch for detecting the brake operation is provided in the middle of a brake wire. 3. The front wheel drive assisted bicycle according to claim 2, wherein the switch is a reed switch. 4. The front wheel drive assisted bicycle according to claim 1, further comprising a switch for detecting a brake operation on the front wheel, wherein the output of the driving unit is stopped even when the front wheel switch is turned on. 5. The front wheel drive according to claim 1, further comprising a torque sensor for detecting a manual driving force, wherein the driving force of the electric driving unit is controlled by a driving force according to a value detected by the torque sensor. Assist bicycle. 6. The front wheel drive assist bicycle according to claim 5, wherein the torque sensor is provided on a sprocket. 7. The front wheel drive assisted bicycle according to claim 5, wherein the torque sensor is formed of an elastic body that expands and contracts according to the magnitude of human power.