JPH0375395B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a suspension system for a power unit in a unit swing type motorcycle or the like.

(Prior art and problems to be solved by the invention) A unit swing type suspension system in which a power unit consisting of an engine, a transmission case, a drive wheel, etc. is pivotally attached to the frame side and is configured to swing vertically. Since such power units are pivoted directly to the vehicle body, there is a disadvantage that vibrations during engine operation and shocks acting on the drive wheels while driving are propagated to the vehicle body frame. Efforts have been made to improve this by interposing an elastic body such as rubber, but this is not sufficient.

Therefore, the present applicant previously proposed a structure in which the vehicle body side and the power unit are connected by a link to suppress the propagation of vibrations and shocks to the vehicle body side.

The present invention relates to an improvement on the earlier application, and an object of the present invention is to suppress the propagation of vibrations and shocks to the vehicle body side, and to alleviate the shocks to the links via an elastic body, Furthermore, it is an object of the present invention to provide a suspension device for a power unit in which such an elastic body can be easily attached.

(Means for Solving the Problems) In order to achieve the above object, the present invention includes a pair of left and right links 15 which are swingably supported on the vehicle body 2 via elastic bushings 17, and these links 1.
5, the power unit 19 is attached to an elastic bush 20.
Elastic bodies 25 and 26 are rotatably supported via the link 15, and a stay 24 is provided integrally with the link 15 and extends in a direction intersecting the longitudinal direction of the link 15, and is separated from the left and right via the stay 24. was attached to the link 15 so as to be able to come into contact with the vehicle body 2.

(Function) Propagation of vibrations and shocks to the vehicle body 2 side is suppressed by the swinging of the link 15, and the impact to the link 15 is suppressed by the elastic body 2.
5,26.

Since the elastic bodies 25 and 26 are arranged apart from each other in the left and right directions, the deflection of the link 15 due to the deformation of the elastic bushes 17 and 20 can be balanced and suppressed in the left and right directions.

(Embodiment) Next, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a scooter as an example of a motorcycle 1, in which a front wheel 4 supported by a front fork 3 is provided at the lower front part of a vehicle body 2, a handle 5 connected to this is provided at the upper part, and a handlebar 5 connected to the front wheel 4 is provided at the upper part. A low-slung floor 6 is provided in the section, and a seat 7 is provided on the rear part.

The main frame 8 is formed of a pipe material with a head tube (not shown) fixed to the front end and has an approximately L-shaped side surface, and has a downward channel at the rear end directly below the seat 7, as shown in FIGS. 2 and 3. A type cross plate 9 is horizontally fixed, and outer channel type left and right rear frames 10 are installed on both sides of the cross plate 9.
10, the lower ends of the rear frames 10, 10 are joined.
The left and right members are parallel to each other, erected upward, forming an inverted L shape, and extending rearward and upward. The middle part of the cross plate 9 in the left and right direction is formed into an inverted concave shape so as to surround the upper rear end and the top of the main frame 8, and forms a flat stopper part 11 on the top of the main frame.
, and on the other hand, the left and right members 1 of the rear frame
Above the main frame between 0 and 10, there are provided stop stays 12 spaced apart in the height direction and facing the stop part 11 which is biased to one side from the center of the vehicle body by a cross member 10a etc. horizontally suspended therebetween.

A bolt forming a support shaft 13 is inserted into the rear end of the main frame 8 so as to pass through the lower part of the rear frame on both sides thereof, and the support shaft 13 passes through a collar 14 that is horizontally suspended at the rear end of the main frame. A support shaft 13 is horizontally fastened to the rear frame members on both sides.
The lower part of link 15 is pivotally connected to. The link 15 consists of left and right members 151 and 152, each of which has an intermediate or lower part facing inside the lower part of the left and right rear frame members 10 and 10, and a collar 16 that penetrates in the left and right direction at the lower part of the members 151 and 152. The collar 16 is provided with collars 17a and 17b on the inner and outer diameter parts, and a rubber bushing 17 with a rubber 17c interposed therebetween is fitted and pivoted around the spindle 13, and the rubber bushing 17 connects the link 15 with the second one. A preload is applied so as to bias it counterclockwise in the figure. The link 15 extends upward, diagonally upward and backward in a substantially dogleg shape in the embodiment, and horizontally suspends the collar 18 between the upper parts, while protruding to the left and right of the front of the power unit 19 consisting of the engine, transmission case, etc. Inner/outer diameter portions 20a,
20b, a rubber bushing 20 with a rubber 20c sewn in between, etc. is fitted, and a bolt forming a support shaft 21 between the inner diameter portions of the rubber bushing 20 is inserted into the collar 18.
The front part of the power unit is pivotally connected between the upper part of the link 15, and the rubber bush 2
0 gives a preload in the counterclockwise direction in FIG. A rear wheel 22 serving as a driving wheel is supported on one rear side of the power unit 19, and a rear action unit is interposed between the rear part of the power unit 19 and the rear part of the rear frame, as is known in the art.

A reinforcing cross member 23 made of pipe material or the like is horizontally fixed between the middle parts of the links 15, and a stopper stay 24 is installed forward in the middle part, and stopper bars 25, 26 are installed above and below this. The rubber 25 faces the stopper stay 12, and the rubber 26 faces the stopper part 11. The stop levers 25 and 26 are arranged offset from side to side, that is, separated from each other from side to side, in consideration of their installation.
Also, the stoppers 12 and 11 are the stoppers 2 and 11.
It is offset corresponding to the offset of 5 and 26.

Next, to explain its functions and effects in detail, the vibrations of the engine forming the power unit are absorbed by swinging around the lower support shaft 13 of the link 15, and the vibrations of the engine are also absorbed by the rubber bushes interposed between the upper and lower supports. This blocks and suppresses vibration propagation to the frame side. In the embodiment, the link 15 is provided diagonally in the vertical direction, so that even if the link length is increased, the power unit does not move rearward due to the layout, and the link length is increased while the power unit is moved forward as close to the frame as possible. can be taken for a long time,
Therefore, it is possible to make the front and rear more compact and increase the vibration suppression effect by setting the link longer.Also, since the front part of the power unit is supported by the upper part of the link, the minimum ground clearance of the power unit can be maintained high, and the link can be made longer. Since it is not hanging down or horizontal, it can have a high ground clearance, and when considering interference from the road surface, it is also advantageous in terms of protecting these parts.In particular, by arranging a link below the front of the engine, it can also be used as an engine guard. Function. The reaction force from the road surface, impact, and reaction force from the rear suspension unit acting on the rear wheels during driving are absorbed by the combined motion of the swinging of the upper fulcrum 21 of the power unit 19 and the swinging of the link 15 from the lower fulcrum. be done.

Vibrations and shocks on the power unit side cause the link 15 to swing back and forth about the lower fulcrum 13 in FIG. 25, 26 collide with the upper or lower stoppers 12, 11, and the elastic deformation of the rubbers 25, 26 absorbs the impact, and the impact from the clockwise and counterclockwise swinging of the link 15 is absorbed by this portion. to relieve it.

Also, link 15 to the stock parabars 25 and 26.
Since the left and right links 15 are offset from each other on both sides, the deflection of the left and right links 15 can be balanced and suppressed, and furthermore, their installation can be performed easily and quickly.

Furthermore, depending on the settings of the stopper levers 25, 26, the stopper portion 11, the stopper stay 12, etc., the compression action of the stopper levers 25, 26 can reduce vibrations caused by the rocking of the power unit 19 itself (vehicle vibrations). It is also possible to effectively absorb vibrations generated due to changes in driving force when oscillation is stopped by the action of the stopper levers 25 and 26 in the shear direction.

(Effects of the Invention) As is clear from the above explanation, the suspension system for a power unit according to the present invention suppresses the propagation of vibrations and shocks toward the vehicle body, and also reduces the impact on the left and right links using the left and right elasticity. The elastic body can be evenly relaxed and the elastic body can be easily attached.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a side view of a motorcycle, FIG. 2 is a side view of a main part of a suspension section by a link, and FIG. 3 is a cross-sectional view taken along line 3-3 in FIG. FIG. 4 is an explanatory perspective view of the same. In the drawing, 8 and 9 are the vehicle body, 15 is the link, 13,
21 is the upper and lower support shaft, 19 is the power unit, 2
5 and 26 are stopper bars.

Claims (1)

[Claims] 1. A suspension system for a power unit comprising a power unit including an engine, a transmission case, a drive wheel, etc., and a shock absorber interposed between the vehicle body and the power unit, in which a pair of left and right links are provided on the vehicle body. The power unit is swingably supported on these links via elastic bushings, and a stay is integrally attached to the links in a direction intersecting the longitudinal direction of the links. A suspension device for a power unit, characterized in that an elastic body is attached to the link so as to extend and to be spaced apart laterally via the stay.