JPH115584A - Drive unit structure for electric motor bicycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect a controller controlling the drive of an electric motor, to prevent the deterioration of outward appearance of a drive unit, to improve the facilitation of assembly and to improve cooling efficiency of the controller, relating to a drive unit structure for an electric motor bicycle. SOLUTION: A controller casing 28a storing a controller 21 is integrally constituted of a casing 28 of a drive unit 20, a female screw is provided in a semiconductor element 43 which is a heating part of the controller 21. By turning a screw inserted from outside the controller casing 28a, in this internal thread, the semiconductor element 43 is directly mounted in an inner wall of the controller casing 28a, and in its outer wall, a cooling fin 28c is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric bicycle having an electric motor such as a DC motor as an auxiliary power source.
The present invention relates to a structure of a drive unit that houses an electric motor as an auxiliary power source of the electric bicycle.

[0002]

2. Description of the Related Art Conventionally, in an electric bicycle (a power assisted bicycle or a bicycle with an auxiliary driving motor) having an electric motor such as a DC motor as an auxiliary power source, a controller for controlling the driving of the motor is provided by a driving unit for housing the motor. In this case, the drive unit is made compact and the overall weight distribution is distributed.

However, in recent years, the object of the present invention is to improve the cooling performance of the controller, improve the appearance, prevent problems such as disconnection by shortening the connection and eliminating the exposure of electric wires, and reduce the number of components. An electric bicycle as disclosed in Japanese Patent Application Laid-Open No. 8-175463 has been proposed. FIG. 6 is a diagram showing a configuration of installing a controller used in such an electric bicycle.

[0004] As shown in FIG.
3 (the controller 043 includes a CPU 043A and a variable resistor 043B) is fixed to the outside of a housing base 052 formed by partially increasing the thickness of a casing 044 of the drive unit with screws or the like. It is covered by a storage cover 053 made of synthetic resin.

[0005] Since the controller 043 is covered by the storage cover 053, the controller 043 is protected and the appearance is prevented from deteriorating. Further, since the controller 043 is arranged close to the motor (not shown), both are connected. Since the length of the electric wire (not shown) is greatly reduced, and the electric wire is built in the casing 044 and is not exposed to the outside, there is no fear of a trouble such as disconnection.

When the motor is driven, the controller 043 generates heat. However, the storage base 052 to which the controller 043 is attached is made of an aluminum alloy. Since the aluminum alloy has excellent thermal conductivity, the storage base 052 itself is formed of the controller 043. As a radiator, the heat of the controller 043 is dissipated to the casing 044 side, whereby the controller 043 is efficiently cooled. In addition, since the casing 044 has a large surface area,
The heat generated at 43 is sequentially radiated to the outside air, so that there is no fear that the casing 044 will overheat.

[0007]

By the way, in the conventional electric bicycle in which the controller is installed in the above-described configuration, the controller storage case is formed by covering a part of the casing of the drive unit with a separate storage cover. Yes,
For example, when using a storage cover made of synthetic resin,
The drive unit made of an aluminum alloy lacks a sense of unity with the casing, and there is a possibility that the desired effect of the appearance is not obtained. Also, in the assembling process, a process of attaching a separate storage cover is required, and the process is complicated.

Further, the heat generated from the controller is transmitted to the casing of the drive unit and is radiated to the outside air through the casing. However, in order to efficiently radiate heat and increase the cooling efficiency of the controller, an outer wall near the base where the controller is installed is provided. It is desirable to increase the surface area so that heat can be efficiently radiated to the outside air. However,
In a conventional electric bicycle, since the controller is attached to the outside of the casing, it is difficult to increase the surface area of the outer wall of the base where the controller is installed, and the heat generated from the controller is opposite to the base, that is, The heat is easily radiated to the inside of the casing, and when the temperature in the casing rises, the heat radiation efficiency decreases.

In addition, when the controller is mounted in the case, if the head of the mounting screw is mounted inside the case as in the conventional case, it is difficult to use a driver, so that the workability deteriorates. If the nut is tightened with a nut, the workability is deteriorated due to the holding of the inner nut, and the nut takes up space and hinders other parts.

[0010] Therefore, it is desired that the mounting structure of the controller when the controller is mounted in the case be made easy. An object of the present invention is to provide a drive unit structure for an electric bicycle that protects a controller, has a beautiful appearance, is easy to assemble, and has excellent controller cooling efficiency. With the goal.

[0011]

According to the present invention, there is provided a drive unit structure for an electric bicycle according to the present invention, wherein a motor as an auxiliary power source of the electric bicycle is housed in a casing. A controller casing accommodating a controller that performs drive control is characterized by being integrally formed with the casing of the drive unit.

According to a second aspect of the present invention, there is provided a drive unit structure for an electric bicycle according to the first aspect, wherein the semiconductor element which is a heat-generating part of the controller is provided on an inner wall of the controller casing. It is characterized by being directly attached to. According to a third aspect of the present invention, in the drive unit structure for an electric bicycle according to the first or second aspect, a female screw portion is provided on the semiconductor element side, and the female screw portion is provided with the controller casing. The semiconductor element is directly attached to the inner wall of the controller casing by screwing a screw inserted from the outside.

According to a fourth aspect of the present invention, there is provided a drive unit structure for an electric bicycle according to any one of the first to third aspects, wherein cooling fins are formed on an outer wall of the controller casing. It is characterized by having been done.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 5 show an electric bicycle having a drive unit structure according to one embodiment of the present invention. 1 and 2 show the entire configuration of the electric bicycle according to the present embodiment, FIG. 1 is a side view of the electric bicycle, and FIG. 2 is a functional block diagram showing a control system and a power transmission system of the electric bicycle shown in FIG. It is.

As shown in FIG. 1, the electric bicycle includes an auxiliary drive unit 20 having a built-in electric motor (hereinafter simply referred to as "motor") 31 (refer to FIG. 2) such as a brushless DC electric motor. The drive unit 20 is attached to a lower end of the frame 17. A crankshaft 14 penetrates the auxiliary drive unit 20, a pedal crank 15 is fixed to both ends of the crankshaft 14, and a pedal 16 is attached to a tip of the crank 15.
Further, a chain 5 is provided.
The driven sprocket wheel 2 attached to the shaft of the rear wheel 7 via a one-way clutch 3 (see FIG. 2) and the drive sprocket wheel 4 coaxial with the crankshaft 14 of the auxiliary drive unit 20 are linked. This allows the driver to depress the pedal 16 to release the crankshaft 14.
Can be transmitted to the rear wheel 7 via the driving sprocket wheel 4 and the driven sprocket wheel 2.

A rechargeable battery 25 serving as a power supply for the motor 31 is provided, and the battery 25 is covered with a decorative cover 18. This decorative cover 18 also covers a part of the drive unit 20. By the way, the drive unit 20
Is provided with a controller 21 for controlling the driving of the motor 31. As shown in FIG. 2, the controller 21 includes a CPU 42 and a power transistor (semiconductor element) 43. This CPU
42 outputs a signal for controlling the motor rotation speed and motor output to the power transistor 43 based on the detection signals from the angular displacement detection mechanism 82 and the vehicle speed detection sensor 89, so that the motor 31
Can be controlled.

Next, referring to FIG.
A description of 0 is as follows. That is,
When the driver depresses the pedal 16, torque is applied to the pedal crank 15 to rotate the crankshaft 14 and rotate the drive sprocket wheel 4 via the one-way clutch 58 and the angular displacement mechanism 81. . The rotation of the driving sprocket wheel 4 is transmitted to the driven sprocket wheel 2 via the chain 5,
The rear wheel 7 is rotated via a one-way clutch 3 provided on a rear wheel hub coaxial with the driven sprocket wheel 2.

On the other hand, the angular displacement mechanism 81 generates a relative angular displacement in proportion to the stepping torque generated by the driver depressing the pedal 16, and this angular displacement (stepping torque) is Displacement detection mechanism 82
Is converted into an electric signal proportional to the angular displacement, and is transmitted to a motor rotation speed / motor output calculation circuit (CPU) 42 built in the controller 21. The CPU 42 calculates an auxiliary torque to be output by the motor by multiplying the stepping torque by an auxiliary ratio (1 or less),
Power transistor 43 built in controller 21
The power supplied from the battery 25 is controlled through the control unit and the motor 31 is controlled. The rotation of the motor 31 is reduced to a required rotation speed by a speed reducer 22 directly connected to an output shaft (not shown) of the motor 31, transmitted to the driving sprocket wheel 4 via a one-way clutch 55, and An auxiliary torque for the stepping torque is generated.

When the angular displacement detecting mechanism 82 detects an angular displacement (stepping torque) equal to or less than a predetermined value, the CPU 42
Sends an instruction to the power transistor 43 to stop the motor 31. Similarly, when the vehicle speed detection sensor 89 detects a speed equal to or higher than a certain speed, the CPU 42 sends an instruction to the power transistor 43 to stop the motor 31. It has become. The speed detection sensor 89 is a proximity-sensitive sensor that detects the teeth of gears (not shown) built in the auxiliary drive unit 30, and the motor 31 of the bicycle that is being driven.
Is measured by substituting the output rotation speed for the number of teeth of the gear passing through the vicinity of the sensing portion of the speed sensor 89 during the unit time. When the bicycle runs only with the driver's stepping torque, the rotation is cut off by the one-way clutch 55, and the rotation of the drive sprocket wheel 4 is not transmitted to the motor 31.

Next, a drive unit for an electric bicycle according to this embodiment will be described with reference to FIGS. FIG.
FIG. 4 is a detailed view of the drive unit of the electric bicycle shown in FIG. 1 and the vicinity thereof, and FIG. 4 is a view taken along the line AA in FIG. 3 and showing a controller of the drive unit.
In FIG. 4, a DC brushless motor 31 is housed in a room surrounded by a motor casing 28 located on one side of the drive unit 20 and the middle wall 26. The motor 31 includes a stator 32 provided with a coil and a rotor 34 having a permanent magnet attached to the circumference. This rotor 34 rotates concentrically with the crankshaft 14,
The rotation is transmitted to the speed reduction mechanism 22. The middle wall 26 separates the motor chamber and the speed reduction mechanism chamber to prevent intrusion of lubricating oil on the speed reduction mechanism side. Reference numeral 25 denotes a reduction mechanism casing, and reference numeral 27 denotes a casing lid. Also, 23
Is a casing in which a stepping torque detecting unit (the angle displacement mechanism 81 and the angle displacement detection mechanism 82) is built. The drive unit 20 is attached to the frame 17 by bolts using three bosses provided on the speed reduction mechanism casing 25 and mounting holes 25a formed in the bosses.

The controller casing 28a for accommodating the controller 21 is formed by projecting a part of the motor casing 28 and is formed integrally with the motor casing 28. And this controller casing 28
a, a circuit board 41 is mounted therein, and control circuit components such as a CPU 42 are disposed on the circuit board 41. A power supply wiring from the battery 25, a rotation speed signal wiring from the speed reduction mechanism 22, and a stepping torque detector ( Angle displacement mechanism 81
And the torque signal wiring and the like from the angular displacement detection mechanism 82) are circuit-coupled. The drive current wiring of the stator 32 of the motor 31 is wired directly to the power transistor 43 along the inner wall of the controller casing 28a, and the switching of the current of the power transistor 43 is controlled by a Hall element (not shown). It is controlled.

The cover 26a of the controller casing 28a
Is formed by an extension of the middle wall 26. The controller housing casing section surrounded by the controller casing 28a and the lid 26a is installed at a position where the controller housing casing section does not interfere with the speed reduction mechanism casing 25 and the stepping torque detecting section casing 23. A thick seat 28b is provided on the inner wall of the controller casing 28a for mounting a power transistor 43, which is a heat-generating component of the controller 21, and the power transistor 43 is directly attached to the seat 28b.

Further, a plurality of cooling fins 28c are provided on the outer wall of the seat 28b to which the power transistor 43 is directly attached. The motor casing 28, the controller casing 28a or the inner wall 26 of the drive unit, and the lid 26a of the controller casing are made of a material having excellent thermal conductivity such as an aluminum alloy.

The electric bicycle according to one embodiment of the present invention is configured as described above.
1 is completely covered by a controller housing casing portion formed by a controller casing 28a and a lid 26a integrally formed with the motor casing 28, and is sufficiently protected from external impacts and the like. Also, the speed reduction mechanism 2
2 to the CPU 42, the rotation speed signal wiring, the stepping torque detecting unit (the angle displacement mechanism 81 and the angular displacement detection mechanism 8).
2) The wiring such as the torque signal wiring from the CPU 42 to the CPU 42 and the wiring such as the driving current wiring from the power transistor 43 to the stator 32 of the motor 31 are completely built in the motor casing 28 and the controller casing 28a. In addition, since the wiring is not exposed to the outside, the occurrence of disconnection or the like is sufficiently prevented.

When the motor 31 is driven, the power transistor 43 generates heat.
The generated heat is passed through the seat 28b to which the power transistor 43 is attached, and the controller casing 28
diverged to a. Since the controller casing 28a is formed integrally with the motor casing 28, the controller casing 28a is made of a material (for example, aluminum alloy) having a large heat capacity and excellent thermal conductivity.
Generated by the controller casing 28a
And is diverged throughout the motor casing 28. And
Controller casing 28a and motor casing 2
Although the heat transmitted to the whole 8 is successively radiated to the outside air, the surface area of the controller casing 28a and the motor casing 28 is large, and the controller casing 28a and the motor casing 28 are overheated without sufficient heat radiation because the surface area is sufficiently in contact with the outside air. No worries.

The cooling fin 28c provided on the outer wall of the seat 28b to which the power transistor 43 is directly attached is
In order to increase the surface area of the controller casing 28a that comes into contact with the outside air, heat is more efficiently radiated to the outside air. As described above, according to the electric bicycle drive unit structure of the present embodiment, the controller 21 can be completely covered by the controller housing casing portion constituted by the controller casing 28a integrated with the motor casing 28 and the lid 26a. Therefore, the controller casing 28a can be sufficiently protected from external impacts and the like. At the same time, since the controller casing 28a is integrally formed with the motor casing 28, the controller casing 28a is compact and has a sense of unity in appearance, and can be beautifully viewed. .

The rotation speed signal wiring from the speed reduction mechanism 22 to the CPU 42, the torque signal wiring from the stepping torque detectors (angular displacement mechanisms 81 and 82) to the CPU 42, and the power transistor 43 to the stator of the motor 31 Since the wiring such as the driving current wiring to 32 is completely built in the motor casing 28 and the controller casing 28a, the wiring path is significantly shortened, and since the wiring is not exposed to the outside, the occurrence of disconnection or the like can be prevented. In addition, since the wiring is not exposed, beautiful appearance can be ensured.

Further, since a dedicated storage cover for covering the controller 21 and a screw for fixing the case to the drive unit are not required, the number of parts can be reduced, and the assemblability is improved and the manufacturing cost is reduced. Can contribute to down. When the motor 31 is driven,
Since the power transistor 43, which is a heat source of the controller 21, is directly attached to the controller casing 28a, which has a large heat capacity and excellent thermal conductivity, and is integrally formed with the motor casing 28, the power transistor 43 generates the power transistor 43. The generated heat can be efficiently dissipated to the entire controller casing 28a and the motor casing 28, whereby the temperature rise of the controller 21 can be effectively suppressed.

Further, a plurality of cooling fins 28c are provided on the outer wall of the seat 28b to which the power transistor 43 is directly attached, and the surface area of the controller casing 28a that comes into contact with the outside air is enlarged, so that the power transistor 43 generates the power more efficiently. The generated heat is released to the outside air, and the temperature rise of the controller 21 can be suppressed more effectively.

By the way, as a specific structure of attaching (directly attaching) the power transistor 43 to the controller casing 28a, the structure shown in FIGS. 5A and 5B can be considered. As shown in FIGS. 5A and 5B,
A female screw portion 43d is provided on the power transistor 43 side, a bolt hole 28d is provided in a seat 28b to which the power transistor 43 is mounted, and a small screw (mounting screw) 44 is passed through the bolt hole 28d from outside the seat 28b. The power transistor 43 is directly attached to the seat 28b by screwing the distal end of the power transistor 44 into the female screw portion 43d.

In this case, as a structure in which the female screw portion 43d is provided on the power transistor 43 side, in addition to a structure in which the female screw portion 43d is directly formed in the main body 43a of the power transistor 43, as shown in FIG. There is a structure in which an inserter 43e having a female screw portion 43d on the inner periphery is fixed in a hole 43f formed in the main body portion 43a, so that the female screw portion 43d is provided via the inserter 43e.

When a bolt hole for attachment provided in a normal power transistor is used, as shown in FIG. 5B, a flange 43g and a female screw 4 are used.
3d and the nut 45b with the bolt hole 43c.
Into the power transistor 4
By fixing the power transistor 43 with an adhesive or the like so as not to rotate with respect to 3, the power transistor 43 can be provided with a female screw portion 43d. 43b is an electrode of the power transistor 43.

According to the mounting structure of the power transistor 43 to the controller casing 28a, the power transistor 43 can be inserted simply by inserting the small screw 44 from the outside of the controller casing 28a, which is easy to work, and screwing it into the female screw portion 43d. To the controller casing 28a
Since it can be mounted inside, there is an advantage that the mounting operation becomes extremely easy as compared with the case where the small screw 44 is inserted from the inside of the narrow controller casing 28a.

The small screw 44 is directly screwed into the female screw portion 43d provided in the power transistor 43. When the small screw 44 is attached from outside the controller casing 28a, the controller casing 2
A mounting nut separate from the power transistor 43, which is required inside the 8a, is not required, so that it is not necessary to hold the nut at the time of mounting. There is also an advantage that a margin is provided and interference with other electronic components and wiring during assembly is eliminated.

In this embodiment, an example has been described in which a power transistor is used as a heat-generating component in a controller. However, the structure of the present invention is applied to a semiconductor element serving as a heat-generating component other than a power transistor. Of course, various applications and modifications are possible without departing from the spirit of the present invention.

[0036]

As described above in detail, according to the drive unit structure for an electric bicycle according to the first aspect of the present invention, the controller casing is formed integrally with the casing of the drive unit, and the controller is formed of the integrated structure. Since it can be stored in the casing, it can be sufficiently protected from external impact and the like.At the same time, since the controller casing is integrated with the drive unit casing, it is compact and has a sense of unity in appearance. In addition, wiring such as signal wiring and drive wiring for electric motors can be completely built into the casing, which greatly shortens the wiring path and disconnects the wiring because the wiring is not exposed to the outside. Etc. can be sufficiently prevented, and at the same time, since the wiring is not exposed, beautiful appearance can be secured. There is a point.

In the drive unit structure for an electric bicycle according to the present invention, a dedicated storage cover for covering the controller, a screw for fixing the case to the drive unit, and the like are not required. There is also an advantage that the number of parts can be reduced, which contributes to improvement in assemblability and reduction in manufacturing cost. According to the drive unit structure for an electric bicycle of the present invention described in claim 2, in addition to the above-described effects and advantages, the semiconductor element, which is a heating component of the controller, is directly attached to the inner wall of the controller casing. There is an advantage that heat generated from the semiconductor element when the motor is driven can be efficiently dissipated to the entire controller casing and the entire casing of the drive unit, and a rise in the temperature of the controller can be effectively suppressed.

According to the drive unit structure for an electric bicycle according to the third aspect of the present invention, in addition to the above effects and advantages, the screw inserted from the outside of the controller casing is screwed into the female screw portion on the semiconductor element side. By doing
Since the semiconductor element is mounted on the controller casing, the mounting operation is facilitated, and there is an advantage that the internal space of the controller casing can have a margin.

According to the drive unit structure for an electric bicycle according to the fourth aspect of the present invention, in addition to the above effects and advantages, the cooling fin formed on the outer wall of the controller casing to which the semiconductor element is directly attached can be obtained. There is an advantage that the surface area of the controller casing in contact with the outside air is increased, and the heat generated from the semiconductor element is more efficiently released to the outside air, so that the temperature rise of the controller can be more effectively suppressed.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing an electric bicycle having a drive unit structure as one embodiment of the present invention.

FIG. 2 is a functional block diagram showing a control system and a power transmission system of the electric bicycle having a drive unit structure according to one embodiment of the present invention.

FIG. 3 is a view showing a drive unit structure for an electric bicycle as one embodiment of the present invention.

FIG. 4 is a sectional view taken along the line AA of FIG. 3, showing a structure of a controller of the electric bicycle drive unit as one embodiment of the present invention.

FIGS. 5A and 5B are diagrams showing a mounting structure of a power transistor to a controller casing, in which FIG. 5A shows an example in which an inserter is used in a female screw portion, and FIG. 5B shows an example in which a sleeve nut is used in a female screw portion.

FIG. 6 is a diagram showing an arrangement structure of a controller in a conventional electric bicycle.

[Explanation of symbols]

 Reference Signs List 20 drive unit 21 controller 28 motor casing 28a controller casing 28b seat 28c cooling fin 28d bolt hole 31 motor (motor) 42 CPU 43 power transistor (semiconductor element) 43a main body 43c bolt hole 43d female screw 43e inserter 44 small screw (screw) 45 Sleeve nut

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[Procedure amendment]

[Submission date] March 26, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0016

[Correction method] Change

[Correction contents]

A rechargeable battery 10 serving as a power supply for the motor 31 is provided. The battery 10 is covered with a decorative cover 18. This decorative cover 18 also covers a part of the drive unit 20. By the way, the drive unit 20
Is provided with a controller 21 for controlling the driving of the motor 31. As shown in FIG. 2, the controller 21 includes a CPU 42 and a power transistor (semiconductor element) 43. This CPU
42 outputs a signal for controlling the motor rotation speed and motor output to the power transistor 43 based on the detection signals from the angular displacement detection mechanism 82 and the vehicle speed detection sensor 89, so that the motor 31
Can be controlled.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0018

[Correction method] Change

[Correction contents]

On the other hand, the angular displacement mechanism 81 generates a relative angular displacement in proportion to the stepping torque generated by the driver depressing the pedal 16, and this angular displacement (stepping torque) is Displacement detection mechanism 82
Is converted into an electric signal proportional to the angular displacement, and is transmitted to a motor rotation speed / motor output calculation circuit (CPU) 42 built in the controller 21. The CPU 42 calculates an auxiliary torque to be output by the motor by multiplying the stepping torque by an auxiliary ratio (1 or less),
Power transistor 43 built in controller 21
The power supplied from the battery 10 is controlled via the power supply and the motor 31 is controlled. The rotation of the motor 31 is reduced to a required rotation speed by a speed reducer 22 directly connected to an output shaft (not shown) of the motor 31, transmitted to the driving sprocket wheel 4 via a one-way clutch 55, and An auxiliary torque for the stepping torque is generated.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0019

[Correction method] Change

[Correction contents]

When the angular displacement detecting mechanism 82 detects an angular displacement (stepping torque) equal to or less than a predetermined value, the CPU 42
Sends an instruction to the power transistor 43 to stop the motor 31. Similarly, when the vehicle speed detection sensor 89 detects a speed equal to or higher than a certain speed, the CPU 42 sends an instruction to the power transistor 43 to stop the motor 31. It has become. The vehicle speed detection sensor 89 is a proximity-sensitive sensor that detects the teeth of gears (not shown) built in the auxiliary drive unit 30, and the motor 31 of the bicycle that is being driven.
Is measured by replacing the output rotation speed with the number of teeth of a gear passing through the vicinity of the sensing portion of the vehicle speed detection sensor 89 during a unit time. When the bicycle runs only with the driver's stepping torque, the one-way clutch 55 is used.
, The rotation of the drive sprocket wheel 4 is not transmitted to the motor 31.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0020

[Correction method] Change

[Correction contents]

Next, a drive unit for an electric bicycle according to this embodiment will be described with reference to FIGS. FIG.
FIG. 4 is a detailed view of the drive unit of the electric bicycle shown in FIG. 1 and the vicinity thereof, and FIG. 4 is a view taken along the line AA in FIG. 3 and showing a controller of the drive unit.
4, a motor 31 is housed in a room surrounded by a motor casing 28 located on one side of the drive unit 20 and the middle wall 26. The motor 31 includes a stator 32 provided with a coil and a rotor 34 having a permanent magnet attached to the circumference. This rotor 3
4 rotates concentrically with the crankshaft 14, and the rotation is transmitted to the reduction mechanism 22. Also, the inner wall 26
Prevents the intrusion of lubricating oil on the reduction mechanism side by separating the motor chamber and the reduction mechanism chamber. 25 is a reduction gear casing, 27
Indicates a casing lid. Reference numeral 23 denotes a casing in which a stepping torque detecting unit (the angle displacement mechanism 81 and the angle displacement detection mechanism 82) is built. The drive unit 20 is attached to the frame 17 by bolts using three bosses provided on the speed reduction mechanism casing 25 and mounting holes 25a formed in the bosses.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction contents]

The controller casing 28a for accommodating the controller 21 is formed by projecting a part of the motor casing 28 and is formed integrally with the motor casing 28. And this controller casing 28
a, a circuit board 41 is mounted thereon, and control circuit components such as a CPU 42 are disposed on the circuit board 41. A power supply wiring from the battery 10 , a rotation speed signal wiring from the speed reduction mechanism 22, Stepping torque detection unit (angular displacement mechanism 81
And the torque signal wiring and the like from the angular displacement detection mechanism 82) are circuit-coupled. The drive current wiring of the stator 32 of the motor 31 is wired directly to the power transistor 43 along the inner wall of the controller casing 28a, and the switching of the current of the power transistor 43 is controlled by a Hall element (not shown). It is controlled.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0031

[Correction method] Change

[Correction contents]

In this case, as a structure in which the female screw portion 43d is provided on the power transistor 43 side, in addition to a structure in which the female screw portion 43d is directly formed in the main body 43a of the power transistor 43, as shown in FIG. , in the formed hole 43f of the main body portion 43a, by fixing the insert 43e provided with a female screw portion 43d on the inner periphery, insert
There is a structure that provided the internal thread portion 43d through the door 43e.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] Explanation of sign

[Correction method] Change

[Correction contents]

DESCRIPTION OF SYMBOLS 20 Drive unit 21 Controller 28 Motor casing 28a Controller casing 28b Seat 28c Cooling fin 28d Bolt hole 31 Motor (motor) 42 CPU 43 Power transistor (semiconductor element) 43a Main body 43c Bolt hole 43d Female screw 43e Insert 44 Small screw (screw) 45 Sleeve nut

[Procedure amendment 8]

[Document name to be amended] Drawing

[Correction target item name] Fig. 1

[Correction method] Change

[Correction contents]

FIG.

[Procedure amendment 9]

[Document name to be amended] Drawing

[Correction target item name] Figure 2

[Correction method] Change

[Correction contents]

FIG. 2

Claims (4)

[Claims] 1. A drive unit for accommodating a motor as an auxiliary power source of an electric bicycle in a casing, wherein a controller casing for accommodating a controller for controlling driving of the electric motor is formed integrally with the casing of the drive unit. A drive unit structure for an electric bicycle. 2. The drive unit structure for an electric bicycle according to claim 1, wherein a semiconductor element as a heat-generating component of the controller is directly attached to an inner wall of the controller casing. 3. A female screw portion is provided on the semiconductor element side,
3. The electric motor according to claim 1, wherein the semiconductor element is directly attached to an inner wall of the controller casing by screwing a screw inserted from outside the controller casing into the female screw portion. 4. Bicycle drive unit structure. 4. The drive unit structure for an electric bicycle according to claim 1, wherein cooling fins are formed on an outer wall of the controller casing.