JPH11255168A - Drive motor control unit arranging structure for motor-driven two-wheeler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively utilize a space for arrangement, to enhance cooling ability for a heating part, and to shorten a wiring length to reduce wiring loss and inductance. SOLUTION: In driving circuit arranging structure for a motor-driven two- wheeler in which the front end part of a power unit 13 constituted by connecting a drive motor 50 to a transmission case 41 with a built-in power transmission for transmitting the rotation of the drive motor 50 to a rear wheel 17 is supported by a body frame freely to be oscillated, a case cover 45 of the transmission case 41 is made of aluminium alloy, a power module (driving circuit) 18b for controlling the rotation of the drive motor 50 is attached to an inner face of a side wall 45a of the case cover 45 so as to operate the side wall 45a as a heat-radiating board.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric motorcycle in which a rear wheel is driven to rotate by a drive motor powered by a battery, and more particularly to an arrangement structure of a drive motor control device for controlling rotation of the drive motor.

[0002]

2. Description of the Related Art In recent years, from the viewpoint of low pollution and low noise,
2. Description of the Related Art Electric two-wheeled vehicles in which wheels are driven to rotate by a drive motor using a battery as a power source have attracted attention. This type of electric motorcycle is equipped with a drive motor control device that controls the rotation of the drive motor according to the throttle input.

A large current flows through the drive motor at the time of starting or climbing a hill, so that parts of the drive motor control device, such as FETs constituting the motor drive circuit (power module), generate heat, and the motor drive circuit generates heat. The temperature is likely to rise depending on the arrangement structure. Conventionally, as a structure for improving the cooling performance of such a drive motor control device, for example, a structure in which a drive circuit is disposed in a storage box below a seat (see Japanese Patent Application Laid-Open No. 4-260886), and a heat sink provided in a motor case And a structure in which a drive circuit is disposed on the heat sink (Japanese Patent Laid-Open No. 5-9560).
No. 6), or a structure in which a drive circuit and a charger are attached so as to sandwich a heat sink has been proposed.

[0004]

However, in the above-mentioned conventional structure in which the drive circuit is arranged in the storage box, the storage capacity of the box is reduced, and the lead wire to the drive circuit interferes with the storage. There is. Further, in the above-described structure in which the drive circuit is disposed in the motor case, there is a problem that the temperature easily rises due to heat generated by both the motor and the drive circuit, and the cooling performance is low.

[0005] Further, in the structure in which the conventional heat sink is shared by the drive circuit and the charger, since it is located at the rear of the vehicle body, it is not possible to utilize the traveling wind and the cooling performance is low, and the wiring to the battery and the drive motor is long. Therefore, there is a problem that wiring loss occurs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional situation, and can be arranged by effectively utilizing a dead space, can secure cooling performance, and can further reduce the wiring length to reduce wiring loss. It is an object of the present invention to provide a drive motor control device arrangement structure for an electric motorcycle.

[0007]

According to the present invention, a drive motor is integrally connected to a front end of a transmission case having a power transmission device for transmitting the rotational force of the drive motor to a rear wheel. In the electric motorcycle, wherein the power unit is swingably supported on a vehicle body frame, the transmission case is made of an aluminum alloy, and at least a drive circuit of a drive motor control device for controlling rotation of the drive motor is provided in the transmission case. The driving circuit is mounted so that the substrate of the driving circuit is in contact with the inner surface of the outer wall of the transmission case.

[0008]

According to the drive motor control device arrangement structure of the present invention, at least the drive circuit of the drive motor control device is provided in the transmission case made of aluminum alloy, and the substrate of the drive circuit is provided on the outer wall of the transmission case. The outer wall of the transmission case functions as a heat radiating plate for radiating heat generated by the drive circuit to the outside, and traveling wind easily hits the outer wall of the transmission case. From that
Heat generated from the components constituting the drive circuit can be efficiently dissipated to the outside, and the cooling performance can be improved.

In the present invention, at least the drive circuit portion of the drive motor control device is housed and arranged in the transmission case, so that the drive circuit is located near the drive motor, and the battery is normally located near the drive motor. Therefore, the drive circuit is also located close to the battery, so that the wiring between the battery, the drive motor and the drive circuit can be shortened, and the wiring loss can be reduced accordingly.

In addition, the drive circuit can be arranged by effectively utilizing the dead space in the transmission case, thereby avoiding the problem that the storage capacity is reduced as in the case where the drive circuit is arranged in the above-mentioned conventional storage box. This has the effect of preventing interference with the camera.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 18 are views for explaining an arrangement structure of a drive motor control device for an electric motorcycle according to an embodiment of the present invention. FIGS. 1 and 2 are a side view, a front view, and a view of a scooter type electric motorcycle. 3 is a cross-sectional front view of the battery housing, FIG. 4 is a cross-sectional plan view of the power unit, FIG. 5 is a side view of the power unit with the cover removed, and FIGS.
FIG. 7 is a sectional view and a side view of the speed change mechanism, and FIGS.
14 is a side view and a cross-sectional view of a shift position detector, FIGS. 10 to 12 are front, side, and plan views of a power module of a control unit. FIG. 13 is a configuration diagram of a drive control device.
Is a characteristic diagram showing the relationship between the throttle opening and the current command value,
15 to 17 are characteristic diagrams showing shift timings, respectively, and FIG. 18 is a partial sectional view of a gear type transmission mechanism.

In FIG. 1, reference numeral 1 denotes a scooter type electric motorcycle, and a body frame 2 of the vehicle has a head pipe 3 connected to a main frame 4 extending obliquely downward and rearward of the vehicle body, and a rear end of the main frame 4. The front end of a pair of left and right side frames 5 and 5 is connected to the rear frame 6 and the rear end of each side frame 5 is connected to a rear frame 6.

The left and right side frames 5 and 5 extend obliquely downward from the main frame 4 while expanding in the vehicle width direction, and then extend horizontally and linearly to the rear of the vehicle body. It bends obliquely upward and extends. Each rear frame 6 extends obliquely upward following the rear end of the side frame 4, and a seat 16 is disposed above the rear frame 6 so as to be vertically rotatable by a front hinge.

A steering shaft 7 is rotatably supported by the head pipe 3. A front fork 8 is fixed to the lower end of the steering shaft 7, and a steering handle 9 is fixed to the upper end, and a front wheel 10 is supported at the lower end of the front fork 8.

The steering handle 9 is provided with a handle cover 20.
Is surrounded by A front cover 21 is attached to the front of the head pipe 3 and a leg shield 22 is attached to the rear of the head pipe 3, and both surround the head pipe 3.
A foot board 23 extending rearward following the lower end of the leg shield 22 is disposed so as to cover the upper part between the horizontal portions of the side frames 5, 5.
An under cover 24 is disposed so as to cover the side and lower sides of the side frames 5 and 5 following the left and right edges of 3. Further, a side cover 25 that covers a lower portion of the seat 16 is provided on the rear frame 6, and a storage box 26 that is opened and closed by the seat 16 is provided in the side cover 25 below the seat 16. .

The under cover 24 and the foot board 2
3, a tunnel-shaped battery storage chamber 35 is provided below the footrest.
The front end opening of the battery storage chamber 35 is closed by an inner cover (front wall) 21a described later, and the rear end opening is opened.

An electric drive unit 14 is suspended and supported by the body frame 2. This electric drive device 14
Are located in the front, rear left,
Four sets of right batteries 15 are suspended and supported by the rear part of the body frame 2, and the rear wheels 17
The power unit 13 is rotated based on a rotation operation (throttle opening) of an accelerator grip 9 a disposed at the right end of the steering handle 9.
And a control unit (drive motor control device) 18 for controlling the amount of power supplied to the motor.

Each of the batteries 15 is composed of a battery group in which a number of rechargeable Ni-Cd batteries 15a are connected in series, and is arranged in a battery case 32. The battery case 32 includes a box 32a fixed by bolts 34 on a pair of front and rear stays 33, 33 welded and fixed to the lower surfaces of the left and right side frames 5, 5, and the box 32a.
And a lid 32b for opening and closing the upper end opening of the lid 3.
2b is detachably fixed to a bracket 31 fixed on the left and right side frames 5 by bolts 31a. Each of the batteries 15 can be taken out by removing the foot board 23 and removing the lid 32a.

The front wall of the box 32a is provided with an air guide port 32c for introducing the running wind into the battery case 32, and the rear wall is provided with an exhaust port 32d for discharging the running wind which has cooled each battery 15. Is open. On the rear side of the rear wall of the battery case 32, a cooling fan 40 for forcibly cooling the battery 15 is provided. A charger 30 is mounted above the cooling fan 40,
Further, a control circuit section 18a of the control unit 18 is mounted above the charger 30.

At the lower end of the front cover 21, an inner cover 21a for preventing muddy water or the like from entering the vehicle body cover is provided. The inner cover 21a is formed below the foot board 23. Battery storage room 3
5 constitute the front wall. The inner cover 21a has a substantially arc shape, and a movable fender 36 that covers the upper part of the front wheel 10 is provided in the inner cover 21a.
The movable fender 36 is attached and fixed near the steering shaft connection portion of the front fork 8. Therefore, the movable fender 36 rotates around the steering axis together with the front wheel 10.

A pair of left and right traveling wind introduction openings 37, 37 are formed in the inclined portion 21b of the inner cover 21a at the front portion of the battery case 32 and at the upper portion thereof. . The left and right traveling wind introduction openings 37, 37 are located above a tangent A of the front wheel 10 passing through the rear lower edge 36a of the movable fender 36 when viewed from the side of the vehicle (see FIG. 1). It is positioned so as to be located within the projection plane of the movable fender 36 when viewed from the front, that is, to be hidden behind the movable fender 36 when viewed from the front of the vehicle (see FIG. 2).

The traveling wind enters the battery chamber 35 from between the movable fender 36 and the inner cover 21a through the traveling wind introduction openings 37, 37, and further enters the battery case 32 through the wind guide port 32c. Pass between the batteries 15a constituting the battery 15, and at this time, each battery 15a
After being cooled, the air is discharged from the air outlet 32d. Thus, an abnormal increase in the temperature of the battery 15 due to discharge during traveling can be suppressed, and deterioration of the battery 15 can be suppressed.

In this case, since the traveling wind introduction opening 37 is located above the tangent line A of the front wheel 10 passing through the rear lower edge 36a of the movable fender 36, muddy water and the like which the front wheel 10 jumps up are moved by the movable fender 36. It is shut off and does not enter the traveling wind introduction opening 37, and therefore the battery 15
Can be prevented from being soiled by muddy water or short-circuited.

Here, the traveling wind introduction opening 37 is seen from the front of the vehicle at the left and right inner covers 21a of the movable fender 36, as shown by a reference numeral 37 '(two-dot chain line) in FIG. It may be formed at a position. In addition,
Even in this case, it is necessary to form the front wheel 10 above the tangent line A of the front wheel 10 when viewed from the side of the vehicle.

When the control unit 18 receives a charge start signal from the charger 30, the battery unit 1
The battery temperature is read from a temperature detector (not shown) arranged at 5, and when the battery temperature is higher than a preset charging start upper limit temperature, the cooling fan 40 is started without charging the battery 15. When the battery temperature falls below the charging start upper limit temperature, charging of the battery 15 is started. The operation of the cooling fan 40 may be continued or stopped during charging.

The power unit 13 includes left and right suspension brackets 1 fixed to the lower surfaces of the left and right rear frames 6.
It is pivotally supported by a pivot shaft 12 fixedly inserted between the upper and lower shafts 11 so as to be vertically swingable. This power unit 13
One shock absorber 19 is interposed between the rear end of the rear frame 6 and the rear frame 6.

The power unit 13 is disposed on the left side of the vehicle and extends in the front-rear direction. The transmission case 41 is made of aluminum die-cast and has an oblong box shape in a side view. It is configured by integrally connecting the arranged drive motor 50.

The transmission case 41 is connected to a case main body 44 supporting a wrapping transmission mechanism 42 as a power transmission device and a gear type speed change mechanism 43 and an outer peripheral mating surface 44a of the case main body 44 so as to be openable and closable. A boss portion 44b formed of a case lid 45 and integrally formed on the upper surface of the front portion of the case body 44 is supported by the pivot shaft 12 via a bearing 51a.

The inside of the transmission case 41 includes a dry-type wrapping chamber 46 formed by the case body 44 and the case lid 45, a rear end of the case body 44, and an inner peripheral surface 4 thereof.
4c is divided into a wet-type gear chamber 48 formed by a lid member 47 mounted thereon, and the wrapping transmission mechanism 42 is provided in the wrapping chamber 46, and the gear-type transmission is provided in the gear chamber 48. A mechanism 43 is provided.

A flange 44d is integrally formed at the right front end of the transmission case 41, and the drive motor 50 fixes the output shaft 50a in parallel with the pivot shaft 12 by bolting to the flange 44d. Have been.
A boss 50b formed on the upper surface of the drive motor 50 is supported by the pivot shaft 12 via a bearing metal 51b, so that the transmission case 41 and the drive motor 50
And swing up and down together. The drive motor 50 is provided with an encoder 52 for detecting the number of rotations and the rotational position of the motor, and a detection value from the encoder 50 is input to the control unit 18.

The winding transmission mechanism 42 has a toothed drive pulley 55 set so that the rotation ratio is approximately 1: 1.
And the toothed driven pulley 56 are connected by a toothed belt 57. A toothed adjustment pulley 58 for adjusting the belt tension is engaged with the slack side of the toothed belt 57. The adjustment pulley 58 is swingably supported by a support arm 59, and the support arm 59 is urged by a spring 60 in the belt tension direction.

The drive shaft 55a of the drive pulley 55 is spline-coupled so as to be coaxial with the output shaft 50a of the drive motor 50. The drive shaft 55a is mounted on a boss 44e formed integrally with the case body 44. It is pivotally supported via 61,61.

The gear type transmission mechanism 43 is provided with the gear chamber 4.
8, a driven shaft 56a, an intermediate shaft 65, and a rear wheel shaft 66 to which the rear wheel 17 is fixed are arranged in parallel with the output shaft 50a, and each gear is meshed. Each axis 5 above
6a, 65, 66 are supported by the case body 44 and the cover member 47 via bearings 67.

The left end of the driven shaft 56a penetrates through the lid member 47 and protrudes into the winding chamber 46. The driven pulley 56 is mounted on the protruding portion. In addition, 67a is an oil seal. A small reduction gear 56b is integrally formed at the right end of the driven shaft 56a.
A large reduction gear 68 fixed to the intermediate shaft 65 meshes with 6b.

A small intermediate gear 65a is formed integrally with the intermediate shaft 65, and a large rear wheel gear 69 rotatably mounted on the rear wheel shaft 66 meshes with the small intermediate gear 65a. A large intermediate gear 70 is mounted on the intermediate shaft 65 so as to be rotatable relative to the intermediate shaft 65 and movably in the axial direction.
The small rear wheel gear 71 fixed to 6 is always meshed. The large intermediate gear 70 is formed with a dog 70a projecting therefrom. When the large intermediate gear 70 is moved in the axial direction toward the large reduction gear 68 (right side), the dog 70a It fits into the hole 68a.

A one-way clutch 72 is interposed between the large rear wheel gear 69 and the rear wheel shaft 66. The one-way clutch 72 has a plurality of ratchet pawls 75 circumferentially interposed between an inner ring 73 fixed to the rear wheel axle 66 and an outer ring 74 fixed to the large rear wheel gear 69. 75 is configured to be urged by an urging spring (not shown) in a direction in which it engages with engagement teeth 74a formed on the inner peripheral surface of the outer race 74. As a result, rotation transmission from the intermediate shaft 65 to the rear wheel shaft 66 is allowed, and rotation transmission from the rear wheel shaft 66 to the intermediate shaft 65 is cut off.

Below the intermediate shaft 65, a fork shaft 76 and a drum shaft 77 are disposed in parallel with the intermediate shaft 65. The fork shaft 76 has a shift fork slidably engaged with the large intermediate gear 70. 78 is mounted so as to be movable in the axial direction. A shift drum 79 is fixed to the drum shaft 77, and a guide groove 79a in which a guide pin 78a of the shift fork 78 is slidably engaged is formed in the outer periphery of the shift drum 79. This guide groove 79
“a” is formed in such a manner that low shift stages “a” and high shift stages “b” are alternately positioned at 90 ° intervals in the circumferential direction (see a development view of FIG. 6), and the shift drum 79 is rotated in one direction. As a result, the shift speed is alternately switched between low and high.

In the above-described gear transmission mechanism 43, in a low gear stage in which the large intermediate gear 70 is not engaged with the large reduction gear 68 and is free to rotate with respect to the intermediate shaft 65, the rotation of the drive motor 50 is transmitted via the winding transmission mechanism 42. From the driven shaft 56a to the intermediate shaft 65 via the large intermediate gear 68,
From the small intermediate gear 65a through the large rear wheel gear 69 and the one-way clutch 72 to the rear wheel axle 66.
6 rotates the rear wheel 17.

When the shift drum 79 is rotated by 90 degrees, the shift fork 78 moves the large intermediate gear 70 in the axial direction toward the large reduction gear 68, and the dog 70a of the large intermediate gear 70 Into the dog hole 68a of
As a result, the large intermediate gear 70 is fixed with respect to the intermediate shaft 65, and is switched from the low gear to the high gear. As a result, the rotation of the drive motor 50 is transmitted from the large intermediate gear 70 of the intermediate shaft 65 to the rear wheel shaft 66 via the small rear wheel gear 71 to rotate the rear wheel 17.

Here, in the high gear stage, the rotation of the intermediate shaft 65 is transmitted to the rear wheel shaft 66 also in the path from the small intermediate gear 65a to the large rear wheel gear 69. The rotation speed of the rear wheel shaft 66 transmitted from the large intermediate gear 70 to the small rear wheel gear 71 is larger than the rotation speed of the rear wheel shaft 66 on this route,
A rotational speed difference occurs between the two, and the rotational speed difference is absorbed by the ratchet pawl 75 of the one-way clutch 72 being released from the engagement teeth 74a of the outer race 74.

The shift drum 79 includes the drum 79
Is maintained at a low gear position or a high gear position. This moderation mechanism is provided by the shift drum 7
9, four pins 80 extending in the axial direction are arranged and fixed at intervals of 90 degrees, and rollers 82 engaged between the pins 80 are fixed.
The roller 82 is pivotally supported by a stopper lever 81, and the stopper lever 81 is
The lever 81 is pivotally biased by a spring 83 in a pin engagement direction.

The shift drum 79 is connected to the spring 8
When the roller 82 is rotated against the biasing force of No. 3, the roller 82 rides on the pin 80 with the rotation, and engages with the biased force between the pin 80 and the adjacent pin 80. In this way, the shift drum 79 is reliably held at either the low gear or the high gear.

The drum shaft 77 projects through the cover member 47 into the winding chamber 46, and a switching mechanism 85 is connected to the projecting portion. This switching mechanism 85
Is a gear case 87 in which a plurality of reduction gear trains 86 are housed.
A switching motor 88 fixed to the gear case 87 to rotationally drive the reduction gear train 86; and a switching shaft 89 pivotally supported by the gear case 87 and driven to rotate by the reduction gear train 86.

Both ends of the switching shaft 89 project outward from the gear case 87, and a switching gear 90 is mounted on one of the projecting portions.
Is a shift gear 9 mounted on the protrusion of the drum shaft 77.
1 is engaged. Here, relief grooves 90a and 91a are formed in the gears 90 and 91, respectively.
a, pins 89a fixed to shafts 89, 77 in
77a is engaged with a predetermined play. This play is
As described later, this is for allowing the drum 79 to rotate faster than the speed corresponding to the rotation of the motor 88 within a predetermined angle range.

The switching motor 88 is driven and controlled by the control unit 18. This switching motor 88
Rotates, the shift drum 79 rotates 90 degrees together with the switching shaft 89 via the reduction gear train 86, whereby the shift fork 78 moves the large intermediate gear 70 in the axial direction. Is performed.

The shift drum 7 is driven by the switching motor 88.
9 rotates, the stopper lever 81 is pushed up in the counter-biasing direction by the rotational force, and the roller 80 rides on the pin 80a. When the shift drum 79 rotates 45 degrees, the center of the roller 80 is in contact with the shift drum 79. Pin 80
When the shift drum 79 slightly rotates from this state, the roller 80 falls between the pin 80a on which it runs and the adjacent pin 80a. It is switched (see FIG. 17).

Here, the rotation from the position where the roller 82 rides on the pin 80 is instantaneously performed by the urging force of the spring 83, so that the shift drum 79 is driven by the motor 88.
, The switching can be performed quickly, the load on the switching motor 88 can be reduced, and the consumption of the battery can be reduced correspondingly. In this case, the difference between the rotation speed according to the rotation of the motor 88 when the shift drum 79 rotates at a high speed is absorbed by the relief grooves 91a and 90a.

A shift position detector 95 is provided at the other projecting portion of the switching shaft 89. The shift position detector 95 has a disk member 96 fixed to the switching shaft 89 so as to rotate together therewith, and a detection member fixed to the outer wall of the gear case 87 and disposed to face the disk member 96. And a substrate 97.

On the detection board 97, a first reed switch 98 for outputting a low gear position detection signal and a second reed switch 99 for outputting a high gear position detection signal are arranged so as to form an angle of 90 degrees. And each of the reed switches 9
Reference numerals 8 and 99 are arranged in a through hole 97 a formed in the substrate 97. In addition, the disk member 96 includes the first magnet 10
0 and a second magnet 101 located on the opposite side of the axis of the first magnet 100 are embedded.

As shown in FIGS. 8 and 9, when the disk member 96 is rotated to the angular position where the first magnet 100 and the first reed switch 98 face each other, the shift position detector 95 receives the first lead. The switch 98 outputs a low gear position detection signal to the control unit 18. At this time, the second magnet 101 is located on the opposite side of the first reed switch 98. When the disk member 96 rotates 90 degrees clockwise (in the direction of arrow a) in this state, the first magnet 100 becomes
As opposed to the second reed switch 99 as indicated by 0 ', the second reed switch 99 outputs a high gear position detection signal. At this time, the second magnet 101 is positioned 90 degrees adjacent to the first reed switch 98 as indicated by reference numeral 101 '. When the disk member 96 further rotates clockwise by 90 degrees, the second magnet 101 faces the first reed switch 98, and a low gear position detection signal is output.

In the shift position detector 95, the shift position is detected by alternately opposing the magnets to the two reed switches. Therefore, compared to a structure in which four reed switches are arranged at 90-degree intervals, for example, The points can be reduced, and the cost can be reduced accordingly. Further, the configuration can be made cheaper than when a potentiometer or the like is employed.

The control unit 18 receives a detection value from a throttle opening sensor, a motor speed sensor, and the like, and outputs a control signal based on a built-in current command value map. And a power module (drive circuit section) 18b for controlling the rotation of the drive motor 50, the switching motor 88, and the like in accordance with the above.

The power module 18b is shown in FIGS.
As shown in FIG. 12, a case 104 in which circuit components such as an FET 106 are disposed is disposed on an aluminum alloy substrate 105, and an electrolytic capacitor 108,
An FET drive gate drive substrate 107 on which a ceramic capacitor 109 and the like are disposed is arranged, and the respective substrates 105 and 107 are connected by connection terminals 110. Lead wires 111 and 112 are connected to the substrates 105 and 107, respectively.
Reference numerals 11 and 112 denote the control circuit 18a, the battery 15,
It is connected to each motor 50, 88 and the like.

As shown in FIGS. 1 and 4, the control circuit 18a constituting the control unit 18 includes the battery 15 in the side cover 25 and the storage box 26.
To prevent ingress of rainwater, dust and the like. The power module 18b is connected to the transmission case 4
1 is provided on a mounting seat 45a in a case cover 45 made of an aluminum alloy. The mounting seat 45a is slightly bulged outward, and the power module 18b
Is the aluminum alloy substrate 10 on the inner surface of the mounting seat 45a.
5 is fixed so that the bottom surface thereof abuts. As a result, the case lid 45 functions as a heat sink, and the FET 10
The heat from the heat-generating components such as 6 is released to the outside.

The control unit 18 functions as motor current control means and shift control means. By the function as the motor current control means, a current command value corresponding to the throttle opening is obtained based on a built-in current command value map, and a current corresponding to the current command value is supplied to the drive motor 50.

In this embodiment, as shown in FIG. 14, the motor rotation speed is, for example, 2000 rpm, 5000 rpm.
In a deceleration operation range in which the throttle opening is closed from a state as high as pm, regenerative current flows and control is performed so that so-called engine braking occurs.

The following operation is performed by the function as the shift control means. When the motor speed from the encoder 52 of the drive motor 50 exceeds a preset shift reference value, a shift signal for switching to either the low shift stage or the high shift stage is output to the switching motor 88. Specifically, FIG.
As shown in the figure, when accelerating on a flat road, the speed is switched from the low speed to the high speed when the motor speed exceeds the standard speed V1, and when decelerating on a flat road, the high speed is changed when the speed falls below the standard speed V2. To the low gear.

In the case of acceleration on an uphill road, the shift to the high gear position is set to a rotation speed higher than the standard rotation speed V1, and at the time of deceleration on an uphill road, the rotation speed is higher than the standard rotation speed V2. The setting is made so that the gear shifts quickly to the low gear. Thereby, the rotation efficiency of the drive motor can be increased, and the hill climbing performance can be improved. Further, during downhill traveling, the gear is set to be switched to the low gear at a rotation speed lower than the standard rotation speed V2, whereby regenerative torque is obtained, and so-called engine braking is applied.

As shown in FIGS. 16 and 17, when the motor rotation speed reaches the shift reference value during the acceleration operation, the current supply to the drive motor 50 is temporarily stopped, and thereafter the switching is performed while supplying the current again. The motor 88 switches from the low gear to the high gear. That is, switching is not performed during a period in which the motor output of the drive motor 50 is cut,
Switching is performed in a re-drive period in which the motor output is restored to a predetermined output while increasing.

During the downhill operation, the driving motor 50
Switching from the high gear to the low gear is performed by the switching motor 88 while increasing the current to the low gear. The increase in the current to the drive motor 50 is performed in a short time before the shift so that the number of revolutions for switching to the high gear can be achieved.

Further, at the time of deceleration operation, the current to the drive motor 50 is increased for a short time and then reduced to a current corresponding to the throttle opening, and the switching gear 88 is switched from the high gear to the low gear.

Further, when the vehicle speed is reduced during the uphill operation despite the accelerator opening being substantially fully open, the gear is switched to the low gear position regardless of the motor speed. In such a switching operation, FIG.
As shown in FIG. 8, the dog 70a of the large intermediate gear 70 is forcibly pulled out from the dog hole 68a of the large reduction gear 68. In this embodiment, a chamfered portion 70b is formed on the pressing surface of the dog 70a in order to reduce the force required for pulling out in this case. As a result, the pressure contact area of the dog 70a against the inner surface of the dog hole 68a can be reduced, the force required for pulling out can be reduced accordingly, and the load on the switching motor 88 can be reduced.

Next, the operation and effect of this embodiment will be described. In the battery cooling structure of the present embodiment, when forming the traveling wind introduction opening 37 for introducing the traveling wind into the housing space of the battery 15 in the inner fender 21a, the opening 37 is connected to the rear lower end of the movable fender 36 of the inner fender 21a. Since it is formed above the tangent line A of the front wheel 10 passing through the edge 36 a, muddy water and the like headed up by the front wheel 10 and traveling toward the traveling wind introduction opening 37 are reliably blocked by the movable fender 36. As a result, deterioration of the battery 15b due to muddy water or the like can be prevented, and the battery life can be extended.

In the present embodiment, the left and right traveling wind introduction openings 37 are formed so as to be located within the projection plane of the movable fender 36 when viewed from the front of the vehicle. Blocked by the fender 36, rainwater and the like can be prevented from entering the traveling wind introduction opening 37, and the battery life can be extended from this point as well.

Since the traveling wind introduction opening 37 is formed in the inclined portion 21b which is inclined forward with respect to the road surface of the inner cover 21a, the traveling wind can be applied to rainwater or the like transmitted through the top wall portion of the inner cover 21a. The battery does not directly enter the introduction opening 37, and the battery life can be extended from this point as well.

In the present embodiment, an exhaust port 32d is formed on the rear wall of the battery case 32, and a cooling fan 40 is provided on the rear side of the rear wall. Since the outside air is forcibly introduced until the battery is cooled down, the battery 15 can be cooled before charging, and it is possible to avoid a decrease in charging efficiency due to charging while the battery temperature is high, and to reduce battery deterioration. Can be prevented.

FIG. 19 is a characteristic diagram showing the relationship between the charging start temperature and the charging efficiency. As is clear from the figure, when the charging start temperature is 50 ° C., the charging efficiency is 0.7
It is as low as 6. On the other hand, the charging start temperature is set to 40
° C and 30 ° C, the charging efficiency is 0.88,0.
It is as high as 96. Therefore, the charging start upper limit temperature is set to 40
C. or lower, more preferably 30.degree. C. or lower.

In the present embodiment, a winding transmission mechanism 42 having a structure in which a toothed belt 57 is wound around a toothed driving pulley 55 and a toothed driven pulley 56, and intermediate gears 70 and 65 a mounted on an intermediate shaft 65. And the rear gear 71, 69 mounted on the rear wheel axle 66 are provided with a gear type transmission mechanism 43 having a structure for selectively meshing with each other. And surely the rear wheel 17
Can be transmitted to In addition, the gear can be shifted with a simple structure in which the intermediate gear mounted on the intermediate shaft 65 is selectively engaged with the rear wheel gear, and the cost can be reduced.

The gear type transmission mechanism 43 is connected to the intermediate shaft 6.
5, the large and small intermediate gears 65a and 70 and the large and small rear wheel gears 69 and 71 of the rear wheel shaft 66 always mesh with each other, and the large intermediate gear 70 is free to rotate or fixed to the intermediate shaft 65. The low gear stage has a simple structure,
Alternatively, the gear can be switched to a high gear, and the cost can be reduced.

Further, from the intermediate shaft 65 to the rear wheel shaft 66
Rotation transmission to the rear wheel axle 66 to the intermediate shaft 65
Is provided with a one-way clutch 72 for interrupting the transmission of the rotation to the engine, so that the difference in rotation speed between the large rear wheel gear 69 and the small intermediate gear 65a at the time of the high gear stage can be absorbed.

Further, since the one-way clutch 72 is provided, the vehicle can be pushed and moved by light human power without providing a complicated clutch mechanism.

According to the present embodiment, the drive motor 50 and the switching motor 88 are controlled in accordance with the control signal from the control circuit 18a.
The power module 18b as a drive circuit unit for controlling the rotation of the motor is fixed by being in contact with the inner surface of the aluminum alloy case cover 45 in the transmission case 44. , And the heat from the heat-generating components such as the FET 106 can be efficiently radiated to the outside.

Further, since the power module 18b is connected to the drive motor 50 and is disposed in the transmission case 44 disposed immediately adjacent to the battery 15, the wiring from the power module 18b to the battery 15 and the drive motor 50 can be shortened. And the wiring loss can be reduced accordingly. Further, the dead space in the transmission case 44 can be effectively used.

According to the drive control device of this embodiment, a current corresponding to the throttle opening is supplied to the drive motor 50, so that a drive torque corresponding to the throttle opening can be obtained in the acceleration operation range. Regenerative torque is obtained in the deceleration operation range.

In this embodiment, during the acceleration operation, the current supply to the drive motor 50 is temporarily stopped, and thereafter the current is supplied again to switch from the low shift speed to the high shift speed by the switching motor 88. The switching can be performed smoothly without using a clutch mechanism that is normally required to cut off the transmission of the rotational force from the drive motor to the rear wheels, and the cost can be reduced.

Further, when the rear wheel 17 is rotating by inertia, the speed is changed while the motor torque once stopped is increased again, so that the speed is changed compared to the conventional speed change during stop or reduction. Harmony with the rear wheel rotating by inertia can be achieved, and shift shock can be reduced.

During downhill operation, the drive motor 50
Is switched from the high gear to the low gear by the switching motor 88 while increasing the electric current to the rear wheel 17 of the high rotation and the drive motor 50.
As a result, switching can be performed smoothly, and so-called engine braking by regenerative torque can be applied, so that running stability can be improved.

In the present embodiment, during deceleration operation, the current to the drive motor 50 is increased for a short time, and then reduced again to a current corresponding to the throttle opening, while switching from the high gear to the low gear by the switching motor 88. As a result, the dog 70a of the large intermediate gear 70 can easily be disengaged from the large reduction gear 68, so that the switching can be smoothly performed from this point, and the shift shock can be eliminated.

When the vehicle speed decreases even when the accelerator opening is almost fully opened, such as during uphill driving, the shift speed is switched to the low shift speed regardless of the motor speed. Uphill performance can be improved.

[Brief description of the drawings]

FIG. 1 is a side view of a scooter type electric motorcycle according to an embodiment.

FIG. 2 is a front view of the electric motorcycle.

FIG. 3 is a sectional front view of a battery storage portion of the electric motorcycle.

FIG. 4 is a sectional view of a power unit of the electric motorcycle.

FIG. 5 is a side view of the power unit.

FIG. 6 is a sectional view of a speed change mechanism of the power unit.

FIG. 7 is a side view of the speed change mechanism.

FIG. 8 is a side view of a shift position detector of the shift change mechanism.

FIG. 9 is a cross-sectional view of the shift position detector.

FIG. 10 is a front view of a power module of the electric motorcycle.

FIG. 11 is a side view of the power module.

FIG. 12 is a plan view of the power module.

FIG. 13 is a schematic configuration diagram of a drive control device for the electric motorcycle.

FIG. 14 is a diagram showing a relationship between a throttle opening of the drive control device and a motor current command value.

FIG. 15 is a shift timing chart of the drive control device.

FIG. 16 is a shift timing chart of the drive control device.

FIG. 17 is a shift timing chart of the drive control device.

FIG. 18 is a partial cross-sectional view of the gear type speed change mechanism.

FIG. 19 is a characteristic diagram showing a relationship between a charging start temperature and charging efficiency in the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Scooter type electric motorcycle 2 Body frame 13 Power unit 17 Rear wheel 18 Drive motor control device 18b Power module (drive circuit) 41 Transmission case 45 Case cover (transmission case) 45a Inner wall 50 Drive motor

Claims (1)

[Claims] 1. A power unit is integrally connected to a front end of a transmission case including a power transmission device for transmitting a rotational force of the drive motor to a rear wheel. In an electric motorcycle that is swingably supported by a frame, the transmission case is made of an aluminum alloy,
At least a drive circuit of a drive motor control device for controlling rotation of the drive motor is mounted in the transmission case such that a substrate of the drive circuit contacts an inner surface of an outer wall of the transmission case. Drive motor control device layout structure for motorcycles.