JPH075114B2 - Motorcycle - Google Patents

Description

TECHNICAL FIELD The present invention relates to a motorcycle that improves riding comfort or durability.

[Prior Art] In a motorcycle, it is necessary to mount the motorcycle so that the vibration of the internal combustion engine is not transmitted to the vehicle body frame from the viewpoint of riding comfort or durability.

Therefore, for example, as a device provided with a suspension device that blocks the vibration of the internal combustion engine from being transmitted to the vehicle body frame, for example, Japanese Utility Model Laid-Open No. 57-57192, Japanese Patent Laid-Open No. 56-13266 and Japanese Patent Laid-Open No.
-182580 is disclosed.

[Problems to be Solved by the Invention] By the way, when an internal combustion engine is mounted on a motorcycle, for example, the drive shaft of the rear wheel that moves up and down is endlessly affected by the vibration of the mass of the reciprocating portion due to the driving of the internal combustion engine. When driven by the power transmission means, the driving reaction force is applied.

However, all of the conventional ones cut off the transmission of the vibration of the internal combustion engine to the vehicle body frame, and when the drive shaft of the rear wheel that moves up and down is driven by the endless power transmission means, the drive reaction force It is not possible to prevent the vibration generated by being applied to the vehicle body frame from being transmitted.

Moreover, the conventional one has a structure in which the internal combustion engine is supported by the vehicle body frame via an elastic body, but depending on the supporting structure, the precision of the support shaft is poor, or the assembling is troublesome. There is a problem such that the width of the foot becomes wider and the foot is not easily attached to the seat.

This invention has been made against the background of such circumstances,
Prevents vibrations generated by the drive of the internal combustion engine from being transmitted to the vehicle body frame, and blocks transmission of vibrations generated by the drive reaction force by the endless power transmission means for transmitting power to the drive shafts of the rear wheels to the vehicle body frame. You can
Moreover, it is an object of the present invention to provide a motorcycle that can firmly and accurately support an internal combustion engine, further improve assemblability, and prevent the vehicle width from widening due to the support structure.

[Means for Solving the Problems] In order to achieve the above object, the present invention suspends an internal combustion engine having a cylinder in which a cylinder shaft is arranged in a substantially vertical direction on a vehicle body frame, and rear wheels on the vehicle body frame. In a motorcycle in which the output shaft of the internal combustion engine and the drive shaft of the rear wheels are connected via endless power transmission means via a shock absorber, and the front side of the internal combustion engine is a front support part. On the other hand, the rear side of the internal combustion engine is supported on the vehicle body frame by the rear side support portions in the vicinity of the line connecting the front side support portion and the center of gravity of the internal combustion engine, and the support location of the internal combustion engine is the front side support portion and the rear side. There are only two side support parts, and the front support part is provided at a position surrounded by extension lines of an upper limit line and a lower limit line of the endless power transmission means by the vertical movement of the rear wheel. The front support portion has a link arranged in the vehicle front-rear direction, and the front portion of the link is mounted on a support shaft that is fixed by being suspended in the vehicle width direction between the left and right down tubes constituting the vehicle body frame. The left and right down tubes are axially supported via a rubber, while the rear part of the link is axially supported by a support shaft in the vehicle width direction fixed to the front part of the internal combustion engine, and the rear support part of the vehicle body frame. It is characterized in that the rear portion of the internal combustion engine is axially supported via a rubber support shaft in the vehicle width direction.

[Operation] In the present invention, the internal combustion engine having the cylinders in which the cylinder shafts are arranged substantially vertically is elastically supported by the vehicle body frame only at two positions, that is, the front support portion and the rear support portion. The center of gravity of the internal combustion engine is located near the line connecting the side support portions.

The front support part has a link arranged in the vehicle front-rear direction, and the front part of the link is made of a rubber on a support shaft fixed in the vehicle width direction between left and right down tubes constituting the body frame. And the rear part of the link is supported on a support shaft in the vehicle width direction fixed to the front part of the internal combustion engine.
The rear side support portion axially supports the rear portion of the internal combustion engine via a rubber support shaft in the vehicle width direction of the vehicle body frame. Therefore, the vibration in the substantially vertical direction due to the driving of the internal combustion engine and the vibration around the horizontal axis that acts around the center of gravity of the internal combustion engine are effectively dampened at the two positions of the front support portion and the rear support portion, and It is regulated that vibration occurs in the direction of.

Further, the front support part of the internal combustion engine is located at a position surrounded by the extension lines of the upper limit line and the lower limit line connecting the output shaft of the endless power transmission means and the drive shaft, and the rigidity is set high, so that the rear wheels move up and down. Even so, the vibration of the internal combustion engine due to the driving reaction force of the endless power transmission means is reduced.

Further, since the support shaft is hung and fixed in the vehicle width direction between the left and right down tubes constituting the vehicle body frame, the rigidity of the down tube is improved. Furthermore, since the front part of the link of the front support part is supported via the rubber on the support shaft fixed between the left and right down tubes, even if the accuracy of the left and right down tubes of the body frame and the support shaft is poor,
Further, even if the parallelism of the holes of the link is poor, the rubber absorbs the inaccuracy, so that the link can be smoothly operated in response to vibrations and vibration can be prevented, and the assembling property can be improved.

Furthermore, there is enough space between the left and right down tubes, and the front of the front support link is supported by the support shaft that is fixed by hanging the space between the left and right down tubes in the vehicle width direction. Therefore, the width of the vehicle does not become wide due to the support of the front portion of the link, and it is possible to prevent deterioration in foot contact when straddling the seat.

In addition, since the bearing part for the link support shaft and the size of the link itself in the support shaft direction can be secured sufficiently, and the support shaft is supported between both left and right down tubes and is not cantilevered but supported at both ends. The front part of the link is rigidly supported.

[Embodiment] An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a side view of a motorcycle to which the invention is applied, and FIG.
The drawing is a sectional view taken along line II-II of FIG.

In the figure, reference numeral 1 is a vehicle body frame of a motorcycle. The vehicle body frame 1 uses a loop-shaped cradle frame and supports the internal combustion engine 2 so as to surround it.

The left and right down tubes 1a of the vehicle body frame 1, the seat pillar 1b, and the support frame 1c are connected by a connecting portion 3, and the front end portion 4a of a rear arm 4 is pivotally supported by the connecting portion 3.

The rear end portion 4b of the rear arm 4 is vertically movable via a shock absorber 5 provided on the support frame 1c. Rear end 4b
A drive shaft 7 for driving the rear wheel 6 is rotatably supported on the shaft.

Sprocket 9 of output shaft 8 provided in the internal combustion engine 2
And the sprocket 10 of the drive shaft 7 of the rear wheel 6 are connected via a drive chain 11 which is an endless power transmission means.
A V-belt may be used as the endless power transmission means, and in this case, a continuously variable transmission mechanism is adopted.

The internal combustion engine 2 has a cylinder 2a in which a cylinder axis L4 is arranged substantially vertically, and the cylinder 2a stands up along a down tube 1a. The front side of the internal combustion engine 2 is a front support portion A on the down tube 1a, while the rear side of the internal combustion engine 2 is a seat support portion on the rear support portion B near the line 1 connecting the front support portion A and the center of gravity G of the internal combustion engine 2. The internal combustion engine 2 is supported by only the front support portion A and the rear support portion B, which are respectively supported by 1b.

That is, as shown in FIG. 2, the front side support portion A on the front side of the internal combustion engine 2 is integrally formed with a pair of mounting portions 12.
A support shaft 13 in the vehicle width direction is inserted between 12 and. on the other hand,
A support shaft 15 in the vehicle width direction is also inserted between the pair of left and right down tubes 1a via the support cylinder 14, and the support shaft 15 is fixed by being stretched between the pair of left and right down tubes 1a. Support shaft 13 on the internal combustion engine 2 side and support shaft on the down tube 1a side
The links 15 are connected by a link 16, and the link 16 is arranged in the vehicle front-rear direction.

The mounting portion 16a of the link 16 on the internal combustion engine side is a metal bush 17
Is supported by the support shaft 13 via the
Is supported by a support shaft 15 via a rubber 18. rubber
For example, 18 has a predetermined strength and is used as a support shaft.
15 and collar 14 are tightened firmly, collar 14 and link 16
The rocking of is allowed by the deformation of the rubber 18.

The mounting position of the link 16, that is, the front side support portion A of the internal combustion engine 2, when the rear wheel 6 moves upward via the shock absorber 5, when the upper limit line 11a of the drive chain 11 and the wheel 6 move downward Is provided in a range surrounded by lines L2 and L3 that extend the lower limit line 11b.

Further, the rear side support portion B is a pair of mounting portions on the rear side of the internal combustion engine 2.
A stay 20 is provided on the seat pillar 1b at a position corresponding to the mounting portion 19 and the mounting portion 19 and the stay 20 are connected via a rubber 22 by a support shaft 21 in the vehicle width direction.

It should be noted that the rubber 18 of the front support portion A and the rubber of the rear support portion B
The spring constant of 22 is preferably set so as to be inversely proportional to the distance from the center of gravity G for vibration prevention.

Next, the operation of this embodiment will be described.

When the internal combustion engine 2 is driven, an inertial force F in the vertical direction and a rotational torque T of the crankshaft are generated in the arrow direction in FIG. 1 by the mass of the reciprocating portion.

By the way, the internal combustion engine 2 is supported by the vehicle body frame 1 at two points on the center of gravity of the internal combustion engine 2, that is, the front side supporting portion A and the rear side supporting portion B. Vibration in the axial direction is generated, but it is reduced by the front support portion A and the rear support portion B, and it is restricted that the vibration is generated in the other direction, so that the vibration due to the driving of the internal combustion engine 2 is transmitted to the vehicle body. , The minimum two support points effectively prevent it.

Furthermore, when the internal combustion engine 2 is suddenly accelerated or rapidly decelerated by the drive chain 11, the internal combustion engine 2 is pulled backward to add vibration in the front-rear direction, which gives the internal combustion engine 2 complicated vibrations. The pulling force by the chain 11 is
A compression force is applied to the rubber 22 of the mounting portion 19 of the rear side support portion B of the internal combustion engine 2.

On the other hand, in the front side support portion A of the internal combustion engine 2, a tensile force is generated between the link 16 and the support shafts 13 and 15, but the link 1
The mounting positions of 6 are the lower limit position and the upper limit position of the rear wheel 6 that moves up and down, and the upper limit line 11a and the lower limit line 1 of the drive chain 11 are attached.
It is set in a range surrounded by lines L2 and L3 that extend 1b.

Therefore, since the rigidity of the front side support portion A is high, it is possible to reliably receive the tensile force and further to suppress the vibration even when the driving reaction force acts on the internal combustion engine 2.

Even if the parallelism of the support shafts 13 and 15 in the axial direction after assembling and the parallelism of each hole of the link 16 into which they are inserted are poor due to variations in production, the elastic body 18 is provided at the front part of the link 16. Since the down tube 1a is connected to the support shaft 15 of the down tube 1a in the vehicle width direction via the support cylinder 14, the link 16 swings smoothly, and the vibration of the internal combustion engine 2 can be effectively suppressed. .

Also, there is enough space between the left and right down tubes 1a, and use that space to the left and right down tubes 1a.
Since the front portion of the link 16 of the front side support portion A is supported by the support shaft 15 that is fixed by being laid across in the vehicle width direction, when the vehicle width does not become wide and the vehicle straddles the seat, the foot attachment property is improved. Can be prevented from becoming worse.

In addition, the bearing for the support shaft 15 of the link 16 and the size of the link 16 itself in the support shaft 15 direction can be sufficiently ensured accordingly, and the support shaft 15 is hung between the left and right down tubes 1a and is not cantilevered. Since both ends are supported, the front part of the link can be firmly supported.

[Advantages of the Invention] As described above, according to the present invention, the vibration in the substantially vertical direction due to the driving of the internal combustion engine and the vibration around the horizontal axis acting around the center of gravity of the internal combustion engine are generated in two places, the front support part and the rear support part. Effectively suppresses vibration, and regulates the occurrence of vibrations in other directions, thereby cutting off the transmission of vibrations to the vehicle body frame.

In addition, the front support portion of the internal combustion engine is located at a position surrounded by the extension lines of the upper limit line and the lower limit line that connect the output shaft of the endless power transmission means and the drive shaft, and the rigidity is high, and even if the rear wheel moves up and down, the endless power is transmitted. Vibration of the internal combustion engine due to the driving reaction force of the power transmission means is reduced.

In addition, since the support shaft is hung and fixed in the vehicle width direction between the left and right down tubes that make up the vehicle body frame, the rigidity of the down tube is improved, and the support shaft fixed between the left and right down tubes is further fixed. , Since the front part of the link of the front support part is pivotally supported via the rubber, the rubber is used even if the accuracy of the left and right down tubes of the body frame and the support shaft is poor, and the parallelism of the link holes is poor. Since the inaccuracy is absorbed, the link can be smoothly operated in response to the vibration to prevent vibration and the assemblability is improved.

Furthermore, there is sufficient space between the left and right down tubes, and the front part of the link of the front support part is supported by a support shaft that is fixed by hanging the space between the left and right down tubes in the vehicle width direction. Therefore, when the vehicle straddles the seat without increasing the width of the vehicle, it is possible to prevent deterioration in foot contact.

In addition, the bearing for the support shaft of the link and the size of the link itself in the support shaft direction can be sufficiently secured along with it, and since the support shaft is both-ends support hung between the left and right down tubes, the front part of the link is firmly supported. Can support.

[Brief description of drawings]

FIG. 1 is a side view of a motorcycle to which the invention is applied, and FIG.
The drawing is a sectional view taken along line II-II of FIG. 1 ... Body frame, 1a ... Down tube 1b ... Seat pillar, 2 ... Internal combustion engine 5 ... Shock absorber, 7 ... Drive shaft 8 ... Output shaft, 11 ... Endless power transmission means 16 ... Link, 18,22 …… Rubber A …… Front support part B …… Rear support part

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP 56-13266 (JP, A) JP 57-15015 (JP, A) JP 60-13747 (JP, Y2)

Claims (1)

[Claims] 1. An internal combustion engine having cylinders whose cylinder shafts are arranged substantially vertically is suspended on a vehicle body frame, and rear wheels are supported on the vehicle body frame via a shock absorber so as to be vertically movable. In a motorcycle in which an output shaft of an internal combustion engine and a drive shaft of rear wheels are connected via an endless power transmission means, a front side of the internal combustion engine is a front side support part, and a rear side of the internal combustion engine is the front side support part and an internal combustion engine. In the vicinity of a line connecting the center of gravity of the engine, each is supported by the vehicle body frame by a rear side support portion, and the internal combustion engine is supported at only two locations, the front side support portion and the rear side support portion,
Further, the front side support portion is provided at a position surrounded by an extension line of the upper limit line and the lower limit line of the endless power transmission means by the vertical movement of the rear wheel, and the front side support portion has a link arranged in the vehicle front-rear direction. The front portion of this link is rotatably supported via a rubber between the left and right down tubes on a support shaft that is fixed by being suspended in the vehicle width direction between the left and right down tubes that form the vehicle body frame. The rear part of the link is pivotally supported by a support shaft in the vehicle width direction fixed to the front part of the internal combustion engine, and the rear support part is a rear part of the internal combustion engine via a support shaft in the vehicle width direction of the vehicle body frame via rubber. A motorcycle characterized by being configured by axially supporting.