JP2832638B2 - Power unit for electric vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A. Object of the Invention (1) Field of Industrial Application The present invention relates to a motor provided with a drive wheel mounted on a transmission case pivotally supported on a vehicle body. And a power transmission mechanism for rotating the drive wheels by a transmission mechanism and cooling the motor with cooling air introduced through a duct by a cooling fan driven by the motor.

(2) Prior art Such a power unit for an electric vehicle has already been proposed by the present applicant in Japanese Patent Application No. 2-137888.

(3) Problems to be Solved by the Invention By the way, in the electric vehicle power unit, the rotating shaft of the motor is arranged in the left-right direction of the vehicle body, and cooling air is supplied to one end of the rotating shaft. A duct is connected to lead the air. For this reason, the duct projects outward beyond the side surface of the transmission case, and there is a problem that the width of the transmission case in the left-right direction is inevitably increased.

The present invention has been made in view of the above circumstances, and has as its object to reduce the width of the transmission case in the left-right direction by laying out the ducts rationally.

B. Configuration of the Invention (1) Means for Solving the Problems In order to achieve the above-mentioned object, the present invention provides a transmission case which is pivotally supported on a vehicle body by driving a driving wheel around a shaft. An electric vehicle power unit that rotates the drive wheels by a motor and a transmission mechanism provided and cools the motor with cooling air introduced through a duct by a cooling fan driven by the motor; A first feature is that the case is connected to the upper surface of the transmission case within the width in the left-right direction of the case.

According to a second aspect of the present invention, in addition to the first aspect, the duct is connected between a transmission mechanism and a motor.

(2) Operation According to the first feature described above, when the motor provided in the transmission case rotates, the driving force is transmitted to the rear wheels via the transmission mechanism housed in the transmission case to propel the vehicle. The motor that has generated heat is cooled by cooling air introduced through a duct by a cooling fan driven by the motor. At this time, since the duct is connected to the upper surface of the transmission case within the width in the left-right direction of the transmission case, it is possible to prevent the duct from projecting from the side surface of the transmission case and increasing the overall width.

According to the second feature of the present invention, since the duct is connected between the transmission mechanism and the motor, the dead space between the transmission mechanism and the motor can be effectively used.

(3) Example Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is an overall side view of a motorcycle V equipped with a power unit P according to the present invention.
Is composed of a front frame F ₁ , a center frame F ₂ , and a rear frame F ₃ made of steel pipe, and the outside thereof is composed of a leg shield B ₁ , a step floor B ₂ , a rear cover B ₃ , and an under cover B _4. Covered with a synthetic resin body B. The head pipe 1 fixed to the front frame F _1, the front fork 4 is pivotally supported that Jikuka the front wheel Wf through a front cushion 3 at the lower end provided with a steering handle 2 at the upper end. At the rear of the center frame F _2, the front end of the power unit P of the swing type the rear wheel Wr and Jikuka is pivotally supported to freely swing up and down with the pivot 5 at the rear end, the rear top and rear frame F ₃ of the power unit P Is connected via a rear cushion 6. Stand 7 provided on the center frame F ₂ covers the front lower surface of the power unit P in the storage position shown, also functions as a protective member of the driving motor to be described later housed therein. A storage compartment 9 for housing a helmet or the like is provided between the power unit P and the seat 8. This case 9
Is formed of a material that shields magnetism, such as a conductive resin, so that the magnetism generated by the motor M does not affect the contents such as the floppy disk. Center frame F
₂ is provided with a battery box 10 for storing a battery as a power supply for driving the motor. A controller 11 for controlling the driving of the motor M and a charger 12 for charging the battery are provided in front of the head pipe 1.

Next, the structure of the power unit P will be described in detail with reference to FIG. The power unit P has the pivot 5 at the front end.
Is provided with a transmission case 13 which penetrates left and right, and a motor M provided at a front portion thereof and a speed reducer 14 provided at a rear portion thereof are connected via a belt type continuously variable transmission 15.

The transmission case 13 is partitioned into left of the belt type continuously variable transmission housing 13 ₂ and the right motor housing portion 13 ₃ by a partition wall 13 _1, the motor housing 16 is in its motor housing portion 13 ₃ for accommodating Mork M therein Is attached. On the right side of the motor housing 16, a driver housing housing which constitutes a part of the transmission case 13 and houses a driver 25 described later therein.
13 ₄ is mounted, and bolt 1 together with the motor housing 16
Combined at 8. The rotating shaft 19 of the motor M is supported by a ball bearing 20 provided on the motor housing 16 and a ball bearing 21 provided on the inner wall of the transmission case 13. The right end of the rotating shaft 19 is located inside the motor housing 16. Is provided with a cooling fan 22. An intermediate position of the motor M and a belt type continuously variable transmission 15 in the upper surface of the transmission case 13, the lower end of the telescopic duct 23 for introducing cooling air into the motor housing 13 ₃ are connected, the duct 23
Communicates with the inside of the container 9 (see FIG. 1).

As shown in FIGS. 2 and 3, the driver 25 is disposed on the rotary shaft 19 coaxially inside the driver storage housing 13 ₄ are fixed by bolts 24 forms a general hexagon, the sides A number of cooling fins 26 are protruded from the inner surface. A field effect transistor 27 (hereinafter abbreviated as FET), which will be described later, is attached to the outer surface of the driver 25, and a space formed in the center of the driver 25 includes:
A large-capacity capacitor 28 described later is fitted and fixed. Then, the right end of the opening of the motor housing 16 is closed with a cover 29 having an air discharge port 29 ₁ of the louver-like.

The motor M is a DC brushless motor, and has a rotating shaft 19.
Rotor with permanent magnet 32 arranged around iron core 31 fixed to
33, and a stator 37 composed of a coil 36 wound around an iron core 35 fixed with bolts 34 inside the motor housing 16 and disposed facing a magnet 38 fixed to the rotating shaft 19 and an outer periphery thereof. A rotor position sensor 40 including three provided Hall elements 39 is provided.

Thus, the cooling fan 22 allows the duct 9 to be
Cooling air introduced through 23, after cooling the motor M of the motor housing portion 13 _3, reaches the driver storage housing 13 in ₄ via the hole 16 ₁ formed in the motor housing 16, FET 27 and the large It is discharged from the air discharge port 29 ₁ of the cover 29 to cool the capacitor 28.

FIG. 4 is a circuit diagram showing a control system of the motor M.
In order to control the rotation speed, the potential of the potentiometer 42 connected to the accelerator grip 41 of the steering handle 2 and the phase signal of the rotor 33 detected by the rotor position sensor 40 are input to the controller 11. The controller 11
The driver 25 interposed between the motor and the motor M has six FEs.
T27 and the F based on a signal from the rotor position sensor 40.
It includes a switching circuit 45 for controlling the group of ETs 44 and sequentially switching the stator current of the motor M, and the large-capacity capacitor 28 for compensating the reverse voltage of the FET 27.

As shown in FIGS. 5 to 7, a ring-shaped fixed bracket 47 fixed to the middle of the handle pipe 46 of the steering handle 2 is rotatably fitted to the tip of the handle pipe 46.
The accelerator grip 41 is provided between the outer peripheral surface and a cylindrical rotating bracket 48 into which an accelerator grip 41 is press-fitted integrally.
A torsion spring 49 that biases 41 toward the idling position is mounted. Potentiometer 42 operated by the rotating operation of the accelerator grip 41 is provided with a conductor 50 ₁ were printed parallel to the surface of the arc-shaped printed circuit board 50 fixed to the bottom surface of the fixing bracket 47 and a resistor 50 _2, the conductor 50 ₁
And the resistor 50 ₂ are each supplied with a potential of 0 volts and 5 volts. Inside of the fixing bracket 47, the guide plate 51 is a printed circuit board 50 having an arcuate guide groove 51 ₁
And a projection formed on the back surface of a sliding member 52 disposed between the printed board 50 and the guide plate 51.
52 ₁ is supported on the rotary bracket 48 through the guide groove 51 ₁ of the guide plate 51. A metal plate electrically connected to the controller 11 is provided on the front surface of the sliding member 52.
53, is fixed to be in contact simultaneously with the conductive body 50 ₁ and the resistor 50 ₂ of the printed circuit board 50. Thus, the accelerator grip
When 41 is in the illustrated idling position, its metal plate 53
Is about 0.5 volts, and when the accelerator grip 41 is rotated in the direction of the arrow toward the full load position, the potential gradually increases to about 4.5 volts.

Next, the structure of the belt-type continuously variable transmission 15 housed in the transmission case 13 will be described with reference to FIG. 2 again. The belt-type continuously variable transmission 15 includes a drive pulley 61 provided on a rotating shaft 19 protruding from the motor housing 16 side into the transmission case 13.
And a driven pulley 63 provided on a reduction gear input shaft 62 supported at the rear of the transmission case 13, and an endless belt 64 is wound around the pulleys 61 and 63. Drive pulley 61 and the stationary pulley half 61 ₁ secured to the rotating shaft 19, axially slidably supported made movable pulley half 61 ₂ to the rotary shaft 19, the movable pulley half between the ramp plate 65 fixed to the 61 ₂ and the rotary shaft 19 a centrifugal weight 66 is movably arranged in the radial direction. On the other hand, the driven pulley 63 becomes more a reduction gear input shaft 62 stationary pulley half 63 supported on the collar 68 to rotatably fitted through a needle bearing 67 to ₁ and the movable pulley half 63 _2, the The driving force transmitted to the driven pulley 63 is transmitted to the speed reducer input shaft 62 through an automatic centrifugal clutch 69, and the driving force transmitted from the speed reducer input shaft 62 is transmitted through another automatic centrifugal clutch 70. Is transmitted to the driven pulley 63 side.

The reduction gear input shaft 62 is supported by a pair of ball bearings 71, 72 provided in the transmission case 13, and the transmission case 1
An intermediate shaft 76 is supported between the axle 75 of the rear wheel Wr supported by the pair of ball bearings 73 and 74 provided in the third wheel 3.
The rotation of the input gear 77 of the reduction gear input shaft 62 is
Are transmitted to the output gear 80 of the axle 75 via the two intermediate gears 78, 79.

Next, the operation of the embodiment of the present invention having the above-described configuration will be described.

When the accelerator grip 41 is at the idling position and the rotation speed of the motor M is low, the automatic centrifugal clutch 69 is in a disconnected state, and the driving force of the motor M is not transmitted to the rear wheel Wr. When the rotation speed of the motor M is increased by rotating the accelerator grip 41 from this state, the rotation shaft
Centrifugal weight 66 along lamp plate 65 fixed to 19
There moved radially outwardly, moving in a direction approaching the movable pulley half 61 _{and second} drive pulley 61 to the stationary pulley half 61 _1. Thus, with effective radius is increased in the drive pulley 61, the movable pulley half 63 ₂ of the driven pulley 63 is driven in a direction away from the stationary pulley half 63 ₁ via the endless belt 64, the effective radius Decrease. As a result, the reduction ratio of the belt-type continuously variable transmission 15 decreases, and the driven pulley 63
When the rotation speed of the collar 68 that rotates with it increases and the automatic centrifugal clutch 69 is connected and the driving force of the motor M is transmitted to the reduction gear input shaft 62, the rear wheel Wr is driven via the reduction gear 14. You.

The cooling fan 22 provided on the rotating shaft 19 by driving the motor M
There is rotated, relatively clean air within the storage compartment 9 is introduced into the motor housing portion 13 ₃ of the transmission case 13 via the duct 23. After cooling air that has cooled the heat generating coils 36 of the motor M, through the hole 16 ₁ of the motor housing 16 is introduced into the driver storage housing 13 _4, the outer and the cooling fins 26 of the driver 25 which houses therein by passing between to cool the heat-generating member such as FET27 and the large-capacitance capacitor 28 is discharged from the air discharge port 29 ₁ formed in the cover 29 to the atmosphere.

Since the duct 23 for introducing the cooling air into the transmission case 13 is connected to an intermediate position between the motor M and the belt-type continuously variable transmission 15 on the upper surface of the transmission case 13, the duct 23 In addition to avoiding the inconvenience of projecting in the direction to increase the overall width of the transmission case 13, the dead space between the motor M and the belt-type continuously variable transmission 15 can be effectively used.

As described above, the embodiments of the present invention have been described in detail. However, the present invention is not limited to the above embodiments, and various small design changes can be made without departing from the present invention described in the claims. is there.

For example, in the claimed invention, the position at which the duct 23 is connected to the transmission case 13 is not limited to the embodiment, and can be connected to an appropriate position within the width of the transmission case 13 in the left-right direction. The power unit P is not limited to the motorcycle V but can be applied to other vehicles such as a motorcycle.

C. Effects of the Invention As described above, according to the first feature of the present invention, the duct for introducing the cooling air to the motor disposed in the transmission case is provided within the width of the transmission case in the left-right direction. Since the duct is connected to the upper surface, the duct is prevented from protruding outward from the side surface of the transmission case. As a result, the entire width of the transmission case is reduced, and the power unit can be formed compact.

According to the second feature of the present invention, by connecting the duct between the transmission mechanism and the motor, the dead space between the transmission mechanism and the motor can be effectively used, and the power unit can be made more compact. It can be formed.

[Brief description of the drawings]

1 to 7 show one embodiment of the present invention.
The figure is an overall side view of a motorcycle equipped with the power unit, FIG. 2 is a sectional view taken along the line II-II of FIG. 1, and FIG.
FIG. 4 is a circuit diagram showing a control system of the motor, FIG. 5 is a longitudinal sectional view of an accelerator grip showing a structure of a potentiometer, and FIG. 6 is a VI-VI of FIG. 7 is a sectional view taken along the line VII-VII of FIG. 13 ... transmission case, 15 ... belt-type continuously variable transmission (transmission mechanism), 22 ... cooling fan, 23 ... duct, M ... motor, Wr ... rear wheel (drive wheel)

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-22790 (JP, A) JP-A-1-247218 (JP, A) JP-A-4-90982 (JP, A) JP-A-58-1983 109762 (JP, A) JP-A-61-274170 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B60K 1/00-1/04 B62M 9/08 B62J 39/00

Claims (2)

(57) [Claims] A transmission case (1) pivotally supported on a vehicle body.
3) A drive wheel (Wr) is mounted on a shaft, and the drive wheel (Wr) is rotationally driven by a motor (M) and a transmission mechanism (15) provided in the transmission case (13). In a power unit for an electric vehicle, which cools the motor (M) with cooling air introduced through a duct (23) by a cooling fan (22) driven by a motor, the duct (23) is moved to the left and right of a transmission case (13). A power unit for an electric vehicle, wherein the power unit is connected to the upper surface of the transmission case (13) within a width in a direction. 2. The power unit for an electric vehicle according to claim 1, wherein said duct (23) is connected between a transmission mechanism (15) and a motor (M).