JP2900177B2 - Power unit for electric vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A. Object of the Invention (1) Industrial application field The present invention relates to a power unit for a vehicle that uses an electric motor as a power source.

(2) Prior Art A swing type power unit widely used in motorcycles and the like is configured such that a drive wheel is mounted on a rear portion of a transmission case pivotally supported on a vehicle body so as to be vertically swingable. (See Japanese Utility Model Publication No. 2-6296, for example).

(3) Problems to be Solved by the Invention By the way, if an electric motor is used instead of the conventional internal combustion engine as a power source of the power unit, accessories such as an air cleaner, a carburetor, a muffler, a fuel tank, and a starting device are omitted. Therefore, a vehicle having a simple structure and excellent in handleability can be obtained. In particular, in a conventional vehicle using an internal combustion engine as a power source, the space on the rear side surface of the vehicle body is occupied by a muffler. .

The present invention has been made in view of the above circumstances, and has as its object to provide a power unit for an electric vehicle that can effectively use the space on the side of the vehicle body.

B. Configuration of the Invention (1) Means for Solving the Problems In order to achieve the above-mentioned object, the present invention relates to a case in which a rear wheel is mounted on a rear portion of a transmission case having a front portion pivotally supported on a vehicle body so as to be vertically swingable. A power unit for an electric vehicle that transmits a driving force of a motor to a rear wheel via a transmission mechanism housed in the transmission case, wherein the power transmission mechanism and the motor are separated from each other on both left and right sides of a rotation surface of the rear wheel. The first feature is that a space that is open to the outside is formed between the transmission mechanism and the motor, and the transmission shaft between the transmission mechanism and the motor crosses the space in the lateral direction of the vehicle body. In addition to the first feature, a second feature is that the transmission shaft also serves as an input shaft of the transmission mechanism and a rotation shaft of a motor.

The present invention also provides a rear wheel axle mounted on a rear portion of a transmission case that pivotally supports a front portion of the vehicle body so as to swing up and down, and transmits a driving force of a motor to the rear wheel via a transmission mechanism housed in the transmission case. A power unit for an electric vehicle for transmitting, wherein the transmission mechanism and the motor are disposed on left and right sides of a rotation surface of a rear wheel, respectively, and an input shaft of the transmission mechanism crosses the rotation surface of the rear wheel in a lateral direction of the vehicle body. A third feature that the rotating shaft of the motor and the input shaft of the transmission mechanism are connected via a bevel gear, and in addition to the second or third feature, an input shaft of the transmission mechanism is provided. Is arranged coaxially with the swing shaft of the transmission case, and the motor is fixed to the vehicle body.

(2) Operation According to the first feature, the transmission mechanism and the motor are disposed on the left and right sides with the rotating surface of the rear wheel interposed therebetween. It can be used effectively as a mounting space, and the weight of the motor can properly maintain the right and left weight balance of the vehicle body. Also, since the transmission mechanism and the motor are separated from each other in the left-right direction, a space that is open to the outside is formed between them, and the transmission shaft between the transmission mechanism and the motor crosses the space. Cooling of the motor and transmission mechanism by the traveling wind is efficiently performed through the space, and even when a large-diameter tire is used for the rear wheel, mutual interference with the transmission mechanism, the motor, the transmission shaft, etc. is easily avoided. It is possible.

Further, according to the second feature, since the input shaft of the transmission mechanism is also used as the rotating shaft of the motor, the structure is simplified accordingly, and the number of parts is reduced.

Further, according to the third feature, the transmission mechanism and the motor are disposed on the left and right sides with the rotating surface of the rear wheel interposed therebetween. The weight balance of the left and right sides of the vehicle body is properly maintained by the weight of the motor. Further, since the input shaft of the transmission mechanism, which is arranged in the lateral direction of the vehicle body, and the rotating shaft of the motor are connected via the bevel gear, the degree of freedom in selecting the mounting position and the mounting angle of the motor is increased.

Further, according to the fourth feature, since the transmission case swings the transmission mechanism around the input shaft, the motor connected to the input shaft can be fixed to the vehicle body, and as a result, the unsprung load is greatly reduced. Can be reduced.

(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.
Consists of a front frame F ₁ made of steel pipe, a center frame F ₂ , and a rear frame F ₃ , the outside of which consists 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. The container 9 is formed of a material that shields magnetism such as a conductive resin so that the magnetism generated by the motor does not affect the contents such as a floppy disk. Battery box in the center frame F ₂ for accommodating the battery as a power source for driving the motor
10 are provided. Further, a controller 11 for controlling driving of a motor and a charger 12 for charging the battery are provided in front of the head pipe 1. The controller can be provided at the position of 11 ₁ or 11 ₂ shown by a chain line at the rear of the vehicle body, and the charger is also located at the position of 12 _{1 at} the rear of the vehicle or at the position of 12 _{2 at} the center of the vehicle. Can be provided.

Next, the structure of the power unit P will be described in detail with reference to FIG. The front end of the power unit P is the pivot 5
There includes a plan view J-shape of the transmission case 13 through the left and right, the motor M is provided in the right half portion 13 ₁ of the transmission case 13 across the plane of rotation of the rear wheel Wr, the left half Part 1
3 ₂ belt type continuously variable transmission 15 for transmitting the driving force of the motor M to the reducer 14 is housed in, the continuously variable transmission 15 constitute a transmission mechanism of the present invention. A space S open to the outside is formed between the left and right halves 13 ₂ and 13 ₁ , and a transmission shaft 19 extends in the space S in the lateral direction of the vehicle body.
The left half functions as an input shaft of the transmission 15, and the right half functions as a rotation shaft of the motor M.

Right end opening of the motor housing 16 accommodating the motor M therein is closed by a lid member 18 fixed with bolts 17, the mounting flange 16 ₁ formed on the left side is a bolt 24 to the right half portion 13 ₁ of the transmission case 13 It is attached. The rotating shaft of the motor M (that is, the right half of the transmission shaft 19) is connected to the ball bearing 20 provided on the cover member 18 and the two halves 13 ₁ , 13 _{2 of the} transmission case 13.
Are supported by two ball bearings 21 provided in
Between the two ball bearings 21, the rotation shaft (the transmission shaft)
19) is exposed between the two halves 13 ₁ and 13 ₂ of the transmission case 13 so as to cross the rotating surface of the rear wheel Wr.

A cooling fan is provided at the right end of the transmission shaft 19 projecting from the lid member 18.
22 is provided, the outer periphery thereof is covered with a fan cover 23 having an air inlet 23 _1. And the cooling fan 22
Air introduced from the air intake port 23 ₁ by the flows in the motor housing 16 through a hole 18 ₁ of the lid member 18, the right half 13 of the transmission case 13 after cooling the motor M
It is discharged from the through hole 13 ₃ formed in ₁ to the outside. Meanwhile, the rear wheel
Left half portion of the transmission shaft 19 extending in the left half portion 13 in the _second transmission case 13 across the plane of rotation of the Wr is also used as an input shaft of the belt type continuously variable transmission 15.

The motor M is a DC brushless motor, and includes a rotor 33 having a permanent magnet 32 disposed on the outer periphery of an iron core 31 fixed to a rotating shaft (the right half of the transmission shaft 19), and a bolt 34 inside the motor housing 16. Coil 36 wound around fixed iron core 35
And a rotor position sensor 40 comprising a magnet 38 fixed to the rotating shaft and three Hall elements 39 disposed opposite to the outer periphery of the magnet 38.

FIG. 3 is a circuit diagram showing a control system of the motor M.
In order to control the rotation speed of the steering wheel 2, the potential of a 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. Is done. The controller 11
A driver 43 interposed between the motor and the motor M controls six FETs 44 based on six field-effect transistors (hereinafter abbreviated as FETs) and a group of the FETs 44 based on signals from a rotor position sensor 40, and And a switching circuit 45 for sequentially switching the M stator currents.

As shown in FIGS. 4 to 6, 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. Belt type continuously variable transmission 15 includes a drive pulley 61 provided on the left half portion of the transmission shaft 19 which projects from the motor housing 16 side to the left half portion 13 in the _second transmission case 13 and supported on the rear of the transmission case 13 A driven pulley 63 provided on the reduction gear input shaft 62;
An endless belt 64 is wound around 61 and 63. Drive pulley 6
1 is a stationary pulley half 61 ₁ fixed to the transmission shaft 19, axially slidably supported made movable pulley half 61 ₂ to the transmission shaft 19, the movable pulley half 61 ₂ A centrifugal weight 66 is disposed between the power transmission shaft 19 and the ramp plate 65 fixed to the transmission shaft 19 so as to be movable in the radial direction. On the other hand, the driven pulley 63
Becomes more and relatively rotatably fixed pulley half 63 ₁ and the movable pulley half 63 ₂ which is supported on a collar 68 which fits over the needle bearing 67 to the reducer input shaft 62 is transmitted to the driven pulley 63 The generated driving force is transmitted to the speed reducer input shaft 62 via the automatic centrifugal clutch 69. Then, the side surface of the transmission case 13 which accommodates the belt type continuously variable transmission 15 and the automatic centrifugal clutch 69 is closed by a detachable side cover 13 _4.

The reduction gear input shaft 62 includes a ball bearing 70 provided on the transmission case 13 and a ball bearing 72 provided on the reduction gear cover 71.
An intermediate shaft 76 is supported between the transmission case 13 and the axle 75 of the rear wheel Wr also supported by a pair of ball bearings 73 and 74 provided on the speed reducer cover 71. The rotation of the input gear 77 of the reduction gear input shaft 62 is transmitted to the output gear 8 of the axle 75 via the two intermediate gears 78 and 79 of the intermediate shaft 76.
Transmitted to 0.

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 transmission 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 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, its effective radius is reduced I do. As a result, the reduction ratio of the belt-type continuously variable transmission 15 decreases, the rotation speed of the collar 68 that rotates together with the driven pulley 63 increases, and eventually the automatic centrifugal clutch 69 is connected to reduce the driving force of the motor M. When transmitted to the input shaft 62, the rear wheel Wr is driven via the speed reducer 14.

Air introduced from the air intake port 23 ₁ of the fan cover 23 by the cooling fan 22 provided on the rotating shaft of the motor M (the right half portion of the transmission shaft 19), cooling the motor M through the interior of the motor housing 16 After that, the through hole provided in the transmission case 13
13 is discharged from the ₃ to the outside. Further, since the motor M is mounted so as to be offset to the right of the vehicle center line, a sufficient cooling effect can be obtained by the traveling wind.

Since the belt-type continuously variable transmission 15 and the motor M are respectively provided on the left and right sides of the rear wheel Wr, the space on both sides of the vehicle body is effectively used, and the right and left weight balance of the vehicle body is appropriately maintained. Can be. Moreover, since the position of the motor M is deviated from the rotation surface of the rear wheel Wr, there is no risk of interference with the motor M even if the diameter of the rear wheel Wr is sufficiently large.

FIG. 7 shows a second embodiment of the present invention, which is characterized by the arrangement of the motor M.

That is, the motor M is mounted towards its axis of rotation 100 in the longitudinal direction of the vehicle body to the right half portion 13 ₁ of the transmission case 13,
Bevel gear 83 and bevel gear 82 fixed to the right end of the input shaft 81 of the belt type continuously variable transmission 15 fixed to the rotation shaft 100 of the motor M is meshed in the right half portion 13 ₁ of the transmission case 13. In this embodiment as well, a space S open to the outside is formed between the left and right halves 13 ₂ and 13 _{1 of the} transmission case 13, and the input shaft 81 serving as a transmission shaft in the space S is formed in the left-right direction of the vehicle body. Extends across.

Thus, according to this embodiment, even when the motor M having a long axial dimension is mounted, the overall width of the vehicle body can be kept small, and the motor M is moved so that the rotating shaft 100 moves up or down. Can be changed as appropriate, so that the degree of freedom in design increases.

8 and 9 show a third embodiment of the present invention. This embodiment is characterized in that the motor M is supported on the vehicle body side.

The transmission case 13 in this embodiment is a bracket 84 which is welded to the rear frame F ₃ to the left, the bracket 86 which is welded to an intermediate portion of the cross member 85 connecting the rear frame F ₃ of the right and left
The input shaft 81 of the belt type continuously variable transmission 15 housed in the transmission case 13 is supported coaxially with the swing center of the power unit P by being vertically swingably supported via a pair of ball bearings 87, 88. You. On the other hand, a gear housing 89 attached to the motor M is detachably supported on three brackets 90, 91 and 92 welded to the rear frame F ₃ to the right. A bevel gear 82 fixed to the right end of the input shaft 81 of the belt-type continuously variable transmission 16 and a bevel gear 83 fixed to the rotating shaft 100 of the motor M
Are meshed inside the gear housing 89. Further, in this embodiment, a space S opened to the outside is formed between the transmission case 13 and the motor M and the gear housing 89, and the input shaft 81 as a transmission shaft is formed in the space S in the lateral direction of the vehicle body. Extending across.

Thus, according to this embodiment, since the transmission case 13 swings around the input shaft 81 of the belt-type continuously variable transmission 15, the motor M is fixed to the vehicle body side to reduce the unsprung load. Can be. Further, the angle of the rotation shaft 100 of the motor M can be appropriately changed, as in the above-described second embodiment.

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, even when the transmission shaft 19 is used as both the rotation shaft of the motor M and the input shaft of the continuously variable transmission 15 as in the first embodiment, the swing shaft of the transmission case 13 may be arranged coaxially with the input shaft. If
The motor M can be fixed to the vehicle body. The positional relationship between the belt-type continuously variable transmission 15 and the motor M can be switched between left and right. Further, in the second and third embodiments, the intersection angle between the input shaft 81 of the belt-type continuously variable transmission 15 and the rotating shaft 100 of the motor M is not limited to 90 °, but can be increased or decreased as appropriate.

C. Effects of the Invention As described above, according to the first feature of the present invention, the transmission mechanism and the motor are disposed on both the left and right sides with the rotating surface of the rear wheel interposed therebetween, so that the use of the motor makes it unnecessary. The mounting space for the muffler is effectively used as a mounting space for the motor, and the weight balance of the left and right sides of the vehicle body can be appropriately maintained by the weight of the motor. Also, in particular, since the transmission mechanism and the motor are separated from each other in the left-right direction, a space that is open to the outside is formed between them, so that the transmission shaft between the transmission mechanism and the motor crosses the space. ,
The motor and the transmission mechanism can be efficiently cooled by the traveling wind through the space, which is effective in preventing overheating of the motor and the like, and even when a large-diameter tire is used for the rear wheel, the transmission mechanism and the motor are used. In addition, mutual interference with the transmission shaft can be easily avoided, and the length of the transmission mechanism and the power unit in the front-rear direction can be suppressed.

According to the second aspect of the present invention, the transmission shaft also serves as the input shaft of the transmission mechanism and the rotating shaft of the motor, so that the number of parts can be reduced and the structure can be simplified.

According to the third aspect of the present invention, since the transmission mechanism and the motor are disposed on the left and right sides with the rotating surface of the rear wheel interposed therebetween,
The installation space for the muffler, which is no longer necessary due to the adoption of the motor, is effectively used as the installation space for the motor, and the weight of the motor makes it possible to properly maintain the right and left weight balance of the vehicle body. In addition, since the input shaft of the transmission mechanism, which is arranged in the lateral direction of the vehicle body, and the rotating shaft of the motor are connected via a bevel gear, the mounting position and the mounting angle of the motor can be appropriately selected, and especially the axial dimension. This is advantageous when a long motor is used.

Further, according to the fourth aspect of the present invention, since the transmission case swings around the input shaft of the transmission mechanism, the motor connected to the input shaft can be fixed to the vehicle body, and as a result, the unsprung load is reduced. It can be significantly reduced.

[Brief description of the drawings]

1 to 6 show a first embodiment of the present invention. FIG. 1 is an overall side view of a motorcycle equipped with the power unit, and FIG. 2 is a sectional view taken along line II-II of FIG. FIG. 3 is a circuit diagram showing a control system of the motor, FIG. 4 is a longitudinal sectional view of an accelerator grip showing a structure of a potentiometer, FIG. 5 is a sectional view taken along the line V--V of FIG. 4, and FIG. FIG. 4 is a sectional view taken along the line VI-VI of FIG. 4, and FIG. 7 shows a second embodiment of the present invention. FIG. 8 is a sectional view of a power unit corresponding to FIG. FIG. 8 is a partial side view of a motorcycle, and FIG. 9 is a sectional view of a power unit corresponding to FIG. 13 ... transmission case, 15 ... belt-type continuously variable transmission (transmission mechanism), 19 ... transmission shaft, 81 ... input shaft as transmission shaft, 8
2,82 bevel gear, 100 rotating shaft, M motor
S …… Space, Wr …… Rear wheel

 ──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Shoji Hondate 1-4-1 Chuo, Wako-shi, Saitama Pref. Honda Technical Research Institute Co., Ltd. (56) References JP-A-53-93515 (JP, A) 63-75425 (JP, U) 1-62928 (JP, U)

Claims (4)

(57) [Claims] A rear wheel (Wr) is mounted on a rear portion of a transmission case (13) pivotally supported on a vehicle body at a front portion thereof so as to be vertically swingable, and a driving force of a motor (M) is transmitted to the transmission case (13). A power unit for an electric vehicle that transmits power to a rear wheel (Wr) via a power transmission mechanism (15) housed therein, wherein the power transmission mechanism (15) and a motor (M) are connected to a rotating surface of a rear wheel (Wr). A space (S) that is open to the outside is formed between the transmission mechanism (15) and the motor (M), and the transmission mechanism (15) and the motor (M) are separated from each other. A power unit for an electric vehicle, characterized in that a transmission shaft (19, 81) intersects the space (S) in the lateral direction of the vehicle body. 2. The power unit for an electric vehicle according to claim 1, wherein said transmission shaft (19) also serves as an input shaft of said transmission mechanism (15) and a rotation shaft of a motor (M). 3. A rear wheel (Wr) is mounted on a rear portion of a transmission case (13) having a front portion pivotally supported on a vehicle body so as to be vertically swingable, and a driving force of a motor (M) is transmitted to the transmission case (13). A power unit for an electric vehicle that transmits power to a rear wheel (Wr) via a power transmission mechanism (15) housed therein, wherein the power transmission mechanism (15) and a motor (M) are connected to a rotating surface of the rear wheel (Wr). The power transmission mechanism (15)
The input shaft (81) of the motor (M) and the input shaft (81) of the transmission mechanism (15) and the input shaft (81) of the motor (M) and the input shaft (81) of the motor (M). The bevel gear (82,83)
A power unit for an electric vehicle, characterized in that the power unit is connected via a power supply. 4. An input shaft (81) of the transmission mechanism (15) is arranged coaxially with a swing shaft of the transmission case (13),
The power unit according to claim 2, wherein the motor (M) is fixed to a vehicle body.