JPH1179045A - Motorcycle with electric motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the total weight and size of an electric motorcycle frame by minimizing the rigidity of its head pipe insusceptible to loads from road surfaces. SOLUTION: A motorcycle is provided with a motor as the power unit and batteries Ba for feeding the motor in the forward lower portion of its body frame. The body frame is mounted on its main frame 2 in the front with a vertically swingable front swing arm 42, on which a front wheel 3 is held rotatable. The main frame 2 serving also to hold the batteries Ba is provided at its forward portion with a front pivot 41 for journalling the swing arm 42. A large load on the wheel 3 is transmitted by way of the swing arm 42 and the pivot 41 to the battery-holding rigid main frame 2. The main frame 2 thus receives the large load on the wheel 3 reliably, which permits the minimization of the rigidity of the head pipe that is insusceptible to loads from road surfaces and thus reduces the total weight and size of the body frame.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a vehicle body frame structure including a front suspension of a motorcycle with an electric motor.

[0002]

2. Description of the Related Art A front suspension of a motorcycle with an electric motor is disclosed, for example, in Japanese Patent Application Laid-Open No. 8-175777, "A power switching device for an engine and a motor of a motorcycle or the like".
As shown in FIG. 1 of this publication, a telescopic suspension is generally used. In a motorcycle equipped with a telescopic suspension, the suspension and the steering are integrated.

[0003]

The above-mentioned telescopic type suspension is widely used. However, since all loads received by the front wheels from the road surface are applied to the head pipe, the body frame around the head pipe must be made highly rigid. . Further, the motorcycle needs to mount a dedicated battery for driving the motor, and a frame portion for holding a heavy battery needs to have high rigidity, and the weight of the frame is further increased. It was supposed to increase.

[0004]

Accordingly, the present inventors have continued research on a suspension structure that can replace a telescopic suspension in order to reduce the weight of a vehicle body frame.
By reviewing the structure of the suspension system and separating the steering system from the suspension system, we succeeded in adopting another suspension structure. Specifically, in a motorcycle including a motor as a power unit and a battery for supplying power to the motor below a front portion of a body frame, a front swing arm is attached to a main frame at a front portion of the body frame so as to be able to swing up and down, A front wheel is rotatably mounted on the front swing arm, a main frame is a frame for storing the battery, and a front pivot shaft for mounting the front swing arm is disposed at a front portion of the frame.

A large load from the front wheels is transmitted from the front swing arm to the high rigidity main frame holding the battery via the front pivot shaft. For this reason, since a large load from the front wheels can be reliably received by the main frame, rigidity around the head pipe which does not receive a load from the road surface can be minimized, and the entire body frame is lightweight and small ( (Compact).

[0006]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Note that "before", "after",
“Left”, “right”, “up”, and “down” follow the direction viewed from the driver, and Fr indicates the front side, Rr indicates the rear side, L indicates the left side, and R indicates the right side. Also, the drawings should be viewed in the direction of reference numerals. FIG. 1 is a side view of a motorcycle according to the present invention. The motorcycle 1 has a main frame 2 composed of a frame serving also as a battery storage box arranged at the lower center and a front suspension system 4 of a swing arm type for suspending a front wheel 3 at the front of the main frame 2. A steering system 5 different from the front suspension system 4 is attached, and a power unit 6 and a rear suspension system 8 for suspending rear wheels 7 are attached to the rear of the main frame 2. The power unit 6 uses an engine 6a and a motor (electric motor) 6b as driving sources. The front wheel 3 and the rear wheel 7 of the present invention have a particularly large diameter (14 to 20 inches).
Wheel is adopted.

In the motorcycle 1, an air cleaner 11, an exhaust pipe 12, a muffler 13, and a tail pipe 14 are further disposed behind the rear wheel 7 in the drawing, and the vehicle body is moved from front to rear by a front fender 15, a front cover 16, and a front handle cover. 17, a center cowl 18, a rear cowl 19, and a rear fender 21. In addition, 22 is a leg shield, 23 is a horn, 24 is a front lamp, 25 is a handlebar, 25a is a grip, 26 is a seat, 27 is a helmet box, 27A is a helmet, 28 is a tail lamp, 71 is a wind guide duct, and 72 is a wind guide duct. Radiator, 73
Is a fan.

FIG. 2 is a side view around the main frame according to the present invention. The power unit 6 and the rear suspension system 8 will be described. The power unit 6 is swingably mounted on a rear upper portion of the main frame 2 via a rear pivot shaft 31, and the rear wheel 7 is mounted on the power unit 6. A seat rail 32 for mounting the seat 27 and the helmet box 28 in FIG. 1 is mounted on the upper rear portion, and a rear cushion 33 is mounted on the seat rail 32 in front of the rear wheel 7 in the drawing. The combination structure of the main frame 2 disposed below the front of the motorcycle 1, the seat rail 32 at the upper rear of the main frame 2, and the head pipe post 51 at the upper front of the main frame 2 constitutes a body frame 57. It was done.

FIG. 3 is a plan view of the main frame, front / rear suspension system, and steering system according to the present invention. The front swing arm 42 of the front suspension system 4 to be described later moves forward from the front of the main frame 2.
The front wheel 3 is cantilevered by the front swing arm 42, while the power unit 6 is extended rearward from the rear of the main frame 2, and the rear wheel 7 is
Indicates that the cantilever was supported. Since the front swing arm 42 is offset from the vehicle center C to one side (right side) and the power unit 6 is offset from the vehicle center C to the other side (left side), the motorcycle 1 has a good right and left weight balance.

FIG. 4 is a side view of the main frame, front suspension system and steering system according to the present invention. The front suspension system 4 is the main frame 2
From the lower front part through the front pivot shaft 41,
A front swing arm 42 having a character shape is extended, and the front wheel 3 is rotatably attached to the front swing arm 42.
Specifically, a knuckle 43 attached to the front wheel 3 is attached to the tip of the front swing arm 42 so as to be rotatable left and right.

The front suspension system 4 includes a cushioning member 44 for reducing the impact of the front swing arm 42 in the swing direction (impact from the road surface), and a front swing arm 4.
2 and a front damper 45 for reducing the amplitude of vibration in the swing direction. Specifically, a resin spring (buffer member) 44 for reducing the impact of the front swing arm 42 in the swing direction is interposed between the main frame 2 and the front swing arm 42, and the front damper 45 is connected to the main frame 2 and the front swing. Arm 4
This is a configuration attached between the two.

More specifically, the mounting structure of the front damper 45 is such that one end of the front damper 45 is supported by a pivot shaft 46 on the right side (rear side in the drawing) of the base of the head pipe post 51 described later. The other end of 45 is supported by a pivot shaft 47 on the left side of the top of the front swing arm 42. Note that one end of the front damper 45 may be directly attached to the main frame 2.

The steering system 5 has a head pipe post 51 extending obliquely upward from the front upper portion of the main frame 2, a head pipe 52 fixed to the tip of the head pipe post 51, and a handle post 53 attached to the head pipe 52. The steering arm 54 is attached to the lower end of the handle post 53 so as to be rotatable, and the tip (lower end) of the steering arm 54 is connected to the knuckle 43 via a link mechanism 55.

The link mechanism 55 includes the steering arm 5
4 and a second link 55b connected to the knuckle 43. The first link 55a is connected to the front end of the front wheel 3 having a relatively large diameter. Since the link mechanism 55 is arranged in the front wheel 3, the space can be effectively used. Since a sufficient space below and behind the head pipe 52 can be ensured, the degree of freedom in designing the motorcycle 1 is increased. Further, when the step 83 for the occupant is removed from the motorcycle 1 and a scooter-type motorcycle is placed on the low-floor type footrest (step floor) with the feet aligned, sufficient space around the driver's foot is sufficient. Can be secured.

Reference numeral 35 denotes a front brake disk. The caliper 36 is attached to the knuckle 43. A bearing 37 supports the rear pivot shaft 31 (see FIG. 2). A main stand 81, an occupant step 83, and a side stand 84 are attached to a lower rear portion of the main frame 2.

FIG. 5 is a plan view of the main frame, front suspension system, and steering system according to the present invention, in which the link mechanism 55 is shown in an expanded manner. In this drawing, the front swing arm 42 extends forward from the right front portion of the main frame 2 via the front pivot shaft 41 while bending rightward so as to bypass the front wheel 3, while the steering arm 54 is It shows that it extends forward from the lower end of the handle post 53 at the vehicle body center (vehicle center line) C while bending rightward so as to bypass the front wheel 3.

FIG. 3 shows a head pipe post 51.
Is offset from the center C of the vehicle body to one side (left side) by a dimension L, and a front damper (damper) 45 is arranged on the other side (right side) from the center C of the vehicle body and adjacent to the head pipe post 51. This shows that the damper 45 is extended in parallel with the center C of the vehicle body. For this reason, since the front damper 45 can be arranged as close as possible to the vehicle body center C, the bending moment acting on the front damper 45 can be suppressed as much as possible. Therefore, since the strength of the front damper 45 can be reduced,
The front damper 45 can be made compact (small), and can be a mechanism suitable for a swing arm mechanism around the front where there are many restrictions on space. The resin spring 44 is disposed at the center C of the vehicle body. 36a is a piston and 36b is a brake pad.

FIG. 6 is an exploded side view of the main frame and the head pipe post according to the present invention. Generally, the caster angle of the steering slightly changes for each vehicle type. For this reason,
In the case of a body frame integrally formed with a head pipe, every time the caster angle is changed, the body frame is inevitably new.

In this embodiment, the main frame 2 and the head pipe post 51 are separated from each other.
Specifically, the main frame 2 has a frame structure also serving as a battery storage box for enhancing versatility, and is made of an aluminum alloy casting to increase rigidity. Then, a head pipe post 5 is attached to the main frame 2.
1 is attached by bolts B1 (... indicates a plurality, the same applies hereinafter).

By adopting such a structure, even if the type of vehicle changes, the main frame 2 can be shared and only the head pipe post 51 needs to be replaced, which increases the degree of freedom in design. Further, as shown in FIG. 4, a swing arm type front suspension system 4 is adopted so that a large load from the front wheel 3 is received by the highly rigid main frame 2 via the front swing arm 42 and the front pivot shaft 41. Therefore, a large load can be reliably and effectively received by the main frame 2. Therefore, a large load does not act on the head pipe post 51. Further, even when the occupant step 83 is removed from the motorcycle 1 and the scooter-type motorcycle is mounted on the low-floor type footrest (step floor) with the feet aligned, the large load from the front wheel 3 can be reduced. It can be received by the highly rigid main frame 2 via the pivot shaft 41.

FIGS. 7A and 7B are mounting structure diagrams of the resin spring according to the present invention, wherein FIG. 7A shows a cross-sectional structure viewed from the side, and FIG. 7B shows a planar structure. The resin spring 44 is a resin block having elasticity so as to perform a spring action, and penetrates in the left-right direction (the front and back direction in the figure).
It has two holes (the mounting hole 44a and the spring force setting hole 44b). This resin spring 44 is connected to the front pivot shaft 41.
It is attached at a position separated by a predetermined dimension H from the front and at the front of the main frame 2. More specifically, the mounting structure of the resin spring 44 is such that a mounting plate 48 is inserted into a mounting hole 44 a of the resin spring 44, and the mounting plate 48 is mounted on a front portion of the main frame 2.
Is sandwiched between the back of the front swing arm 42 and the holding plate 49 attached to the back of the front swing arm 42.

FIG. 8 is a front view of the main frame and the head pipe post according to the present invention.
5 shows a structure in which one end of the base 5 is supported by a pivot shaft 46 on the right side of the base of the head pipe post 51. Reference numerals 2a and 2a denote bearings for supporting the front pivot shaft 41, and reference numerals 2b and 2b denote mounting portions of a mounting plate 48 for a resin spring.

FIG. 9 is an exploded perspective view of the main frame, front suspension system and steering system according to the present invention. This figure illustrates the structure of the front suspension system 4 and the steering system 5 in more detail. The support pipe 42a of the front swing arm 42 is mounted on the left and right bearings 2a, 2a of the main frame 2 by the front pivot shaft 41. And the holding plate 49 is connected to the connecting portions 42c and 42c formed on the plate portion 42b of the front swing arm 42 by two upper and lower bolts B2 and B2.
b, the resin spring 44 is sandwiched between the holding plate 49 and the holding plate 49, and the mounting plate 4 is inserted into the mounting hole 44 a of the resin spring 44.
8 and the left and right ends of the mounting plate 48 are mounted on the mounting portions 2b, 2b of the main frame 2 with bolts B3, B3. Further, a head pipe post 51 is mounted on the front upper portion of the main frame 2 with bolts B1,. At the base of the head pipe post 51, one end of a front damper 45 is supported by a pivot shaft 46, and at the top of the front swing arm 42, the other end of the front damper 45 is supported by a pivot shaft 47. A head pipe 52 is provided at the tip of the post 51, a handle post 53 is rotatably attached to the head pipe 52, a steering arm 54 is attached to a lower end of the handle post 53, and a link mechanism 55 is connected to the tip of the steering arm 54. Indicates that you have done. The front swing arm 42 is provided with a stem receiver 42d for attaching a stem shaft 43a (see FIG. 4) of the knuckle 43 to the end so as to be rotatable left and right.

FIG. 10 is a plan view of the main frame in the battery storage state according to the present invention, and shows that a plurality of batteries Ba are stored in the main frame 2. That is,
A plurality of batteries Ba are provided below the front part of the body frame 57. Specifically, the main frame 2 extends left and right side members 2c, 2c in the front-rear direction on both sides of the vehicle body, and joins the front ends of the left and right side members 2c, 2c with a front cross member 2d. The rear ends of the left and right side members 2c, 2c are joined to each other by a rear cross member 2e in the shape of a rear gate.

For this reason, the main frame 2 has a shape in which the bottom at the center is removed except for the front part. A storage case 61 also serving as a bottom plate is attached to the main frame 2, and most of the five batteries Ba. Is to be placed. The plurality of batteries Ba supply electric power to the motor 6b in FIG. 1, and include left and right side members 2c, 2c.
It is mounted in a zigzag manner in three rows between the points c and two rows in the front-rear direction. Therefore, the main frame 2 is wide.

FIG. 11 is a side sectional view of the main frame in the battery storage state according to the present invention, and shows that the rear cross member 2e having a gate shape is formed so as to extend over a plurality of batteries Ba.

FIG. 12 is a sectional view taken along line 12-12 of FIG.
1 indicates that it is closed. The storage case 61 includes the motor 6b.
A case made of a light alloy for accommodating a unit (not shown) including an electronic circuit or the like for driving and controlling (see FIG. 1), and includes a case body 62 and a lid 63 for closing an upper portion of the case body 62. . The storage case 61 is inserted into the opening of the main frame 2 from below, and the flange 62 a
Are attached to the lower surface of the main frame 2 with bolts B4. Hereinafter, a combination structure of the storage case 61 and the units stored in the storage case 61 is referred to as a control unit. As described above, the main frame 2 extends below the head pipe 52, and thereafter includes a pair of left and right side members (frames) 2c, 2c substantially parallel to the ground, and forms a part of the body frame 57. It is a member. The present invention is provided at the lower portion between the left and right side members 2c, 2c, and
The control unit is fixed between the left and right side members 2c, 2c, and a plurality of batteries Ba are mounted on the control unit.

Further, on the storage case 61, a resin partition plate 64 for partitioning between a plurality of batteries Ba is stacked from above the main frame 2, and the partition plate 64 is mounted on the upper surface of the main frame 2 with bolts B5. It is a thing. The presence or absence of the partition plate 64 is optional. On the other hand, a plurality of batteries Ba are covered with a battery cover 65, and a flange 65a of the battery cover 65 is mounted on the upper surface of the main frame 2 with bolts B5.

As described above, most of the batteries Ba... Are placed in the storage case 61 which also serves as the bottom plate of the main frame 2, so that a member such as a tray for receiving the batteries Ba. Reduction can be achieved.
Further, since the bottom of the main frame 2 is closed by the storage case 61, the rigidity of the main frame 2 is increased. Further, since the storage case 61 is exposed below the main frame 2, the heat radiation from the unit is enhanced. Moreover, since the heat radiation fins 62b are formed on the lower surface of the storage case 61, the heat radiation is further improved. Since the storage case 61 is a light alloy case having good thermal conductivity, the heat generated by the batteries Ba can be easily dissipated.

Next, the reason why the front swing arm 42 has a substantially inverted U-shape in side view will be described with reference to FIG.
FIGS. 13A to 13C are explanatory diagrams showing the relationship between the front swing arm and the front wheels. In (a), a member shown by a solid line is a front swing arm 4 employed in the embodiment of the present invention.
2, and the member indicated by the imaginary line is the front swing arm Fa of the comparative example. The front swing arm 42 is substantially inverted U in side view.
The front swing arm 42 and the outer peripheral edge of the front wheel 3 overlap at the position of the point P1 approaching the center O of the front wheel. On the other hand, the front swing arm F of the comparative example
a is an arm extending horizontally at the center height of the front wheel 3,
The front swing arm Fa and the outer peripheral edge of the front wheel 3 overlap at a point P2 farthest from the front wheel center O.

FIG. 3C is a plan view showing the relationship between the front swing arm Fa and the front wheel 3 of the comparative example, and the front wheel 3 is steered by a steering angle θ.
When only the steering is performed, the inclination distance from the vehicle body center C to the outer edge of the front wheel 3 is S2. Front swing arm Fa of comparative example
Needs to be detoured by a large inclination distance S2 so as not to hit the front wheel 3. For this reason, the protrusion amount of the front swing arm Fa in the vehicle width direction is large.

FIG. 3B is a plan view showing the relationship between the front swing arm 42 and the front wheel 3 employed in the embodiment of the present invention.
1 so that the front wheel 3 is steered by the steering angle θ.
When only the steering is performed, the inclination distance from the vehicle body center C to the outer edge of the front wheel 3 is S1, and the inclination distance S2
Less than. For this reason, the front swing arm 42 may be detoured by a small inclination distance S1 so as not to hit the front wheel 3, and the protrusion amount in the vehicle width direction may be small. Since the protrusion amount of the front swing arm 42 is small, the motorcycle becomes small. That is, the front swing arm 42 having a substantially inverted U-shape in a side view and the outer peripheral edge of the front wheel 3 overlap at a position higher than the center O of the front wheel (position of the point P1). The swing width of the steered front wheel 3 at this overlapping position is smaller than the swing width of the outer peripheral edge of the front wheel 3 at the height of the front wheel center O. Therefore, the front swing arm 42 may be detoured at a position where the swing width of the front wheel 3 is small so as not to hit the front wheel 3.

Next, the operation of the front suspension system 4 will be described with reference to FIGS. The front damper 45 in FIG. 4 reduces the amplitude of the vibration of the front swing arm 42 in the swing direction. On the other hand, in FIG. 7, the impact force in the upper swing direction of the front swing arm 42 is transmitted from the back surface of the front swing arm 42 to the resin spring 44, and the impact force in the lower swing direction of the front swing arm 42 is transmitted from the holding plate 49. The power is transmitted to the resin spring 44. At this time, the resin spring 44 is elastically deformed to form a spring action, thereby reducing the impact force. As described above, the front suspension system 4 reduces the impact force by the resin spring 44 and reduces the amplitude of the vibration by the front damper 45.

As described above, the resin spring 44 performs a spring action with a small stroke that is only elastically deformed, and can cope with a wide range of loads from a small load to a large load. Moreover, the resin spring 44 is extremely small as compared with the coil spring. Therefore, as compared with the conventional suspension in which the coil spring and the damper are integrally incorporated, the suspension has a small stroke with respect to a wide range of loads, is small, and can be easily arranged in a small space. .

[0035]

According to the present invention, the following effects are exhibited by the above configuration. According to a first aspect of the present invention, a front swing arm is mounted on a front main frame of a body frame so as to be able to swing vertically, a front wheel is rotatably mounted on the front swing arm, and the main frame is a frame for storing a battery. Since the front pivot shaft for mounting the front swing arm is disposed at the front of the vehicle, a large load from the front wheels is transmitted from the front swing arm to the high-rigidity main frame holding the battery via the front pivot shaft. This allows the main frame to reliably receive the large load from the front wheels,
The rigidity around the head pipe that does not receive a load from the road surface can be minimized, and the entire body frame can be made lightweight and small (compact).

[Brief description of the drawings]

FIG. 1 is a side view of a motorcycle according to the present invention.

FIG. 2 is a side view around a main frame according to the present invention.

FIG. 3 is a plan view of a main frame, a front / rear suspension system, and a steering system according to the present invention.

FIG. 4 is a side view of a main frame, a front suspension system, and a steering system according to the present invention.

FIG. 5 is a plan view of a main frame, a front suspension system, and a steering system according to the present invention.

FIG. 6 is an exploded side view of the main frame and the head pipe post according to the present invention.

FIG. 7 is a mounting structure diagram of a resin spring according to the present invention.

FIG. 8 is a front view of a main frame and a head pipe post according to the present invention.

FIG. 9 is an exploded perspective view of a main frame, a front suspension system, and a steering system according to the present invention.

FIG. 10 is a plan view of a mainframe in a battery storage state according to the present invention.

FIG. 11 is a side sectional view of the main frame in a battery storage state according to the present invention.

FIG. 12 is a sectional view taken along line 12-12 of FIG. 11;

FIG. 13 is an explanatory diagram showing a relationship between a front swing arm and front wheels.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Motorcycle, 2 ... Main frame, 3 ... Front wheel, 41
... front pivot shaft, 42 ... front swing arm, 43 ... knuckle for front wheels, 54 ... steering arm, 55 ... link mechanism.

Claims (1)

[Claims] 1. A motorcycle comprising a motor as a power unit and a battery for supplying power to the motor below a front portion of a vehicle body frame, wherein a front swing arm is attached to a main frame at a front portion of the vehicle body frame so as to be vertically swingable. A front wheel is rotatably mounted on the front swing arm, the main frame is a frame for storing a battery, and a front pivot shaft for mounting the front swing arm is disposed at a front portion of the frame. Motorcycle with electric motor.