JPS61247582A - Suspension system for power unit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

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.

(Problems to be solved by the prior art and the invention) A 1,000-knit swing suspension system in which a power unit consisting of an engine, transmission case, drive wheels, etc. is pivotally attached to the frame side and can swing up and down. Since such a power unit is pivoted directly to the vehicle body side, there is a disadvantage that vibrations during engine operation and shocks acting on the drive wheels during driving are transmitted to the vehicle body frame, so the pivot point An attempt has been made to improve this by interposing an elastic body such as rubber, but it cannot be said to be 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.
It is an object of the present invention to provide a suspension device for a power unit in which the impact on the link can be relaxed through an elastic body, and furthermore, the attachment of the elastic body can be easily performed.

(Means for Solving the Problems) In order to achieve the above object, the present invention has the front end of the link (15) pivotally supported on the vehicle body (2) side, and the rear end pivotally supported on the power unit (18) side. , the link (15) is attached to the intermediate portion of the front and rear shaft portions of the link (15).
A stay (20) extending in a direction intersecting the longitudinal direction of the link (15) is provided, and an elastic body (25), ( 213
), and the elastic bodies (25) and (2B) were arranged offset from each other on both sides of the stay (20) in the swinging direction.

(Function) Propagation of vibrations and shocks toward the vehicle body (2) is suppressed by the swinging of the link (15), and the impact to the link (15) is suppressed by the elastic body (25).
'), (2B).

Since the elastic bodies (25) and (2B) are arranged offset from each other on both sides of the swinging force direction of the link (15), the elastic bodies (25) and (2B) can be easily attached. .

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

Figure 1 shows a scooter as an example of a motorcycle (1), with a front fork (3) at the lower front of the vehicle body (2).
The front wheel (0) is supported by a handle (5) connected to the front wheel (0), and a handle (5) connected to this is provided at the top, a low floor (8) is provided in the middle part, and a seat (7) is provided on the rear part. is provided.

The main frame (8) is formed of a pipe material with a not-shown Herad tube fixed to the front end, and has a sidewall shape, as shown in FIG.
As shown in Fig. 3, a downward channel type cross plate (8) is horizontally fixed to the rear end directly below the seat (7), and outer channel type left and right carrier frames are mounted on both sides of the cross plate (9). The lower ends of (10) and (10) are joined, and the left and right members of the rear frame (10) and (10) are parallel, erected upward, forming an inverted shape, and extending rearward and upward. . The middle part of the cross plate (8) 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) to form a flat stopper part (11) on the top of the main frame. Above the main frame between the left and right members (10) of the rear frame, there is a stopper that faces the above-mentioned stopper part (11) that is biased to one side from the center of the vehicle body by a cross member (10a) etc. suspended horizontally between the members (10). The stays (12) are provided spaced apart in the height direction.

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) is suspended horizontally at the rear end of the main frame. A link (1
5) Pivotally attach the lower part. The link (15) is the left and right member (
151), (152), each of which has its middle or lower part facing inside the lower part of the left and right rear frame members (10), (10), and the lower part of the members (151), (152) has a A penetrating collar (18) is provided and the collar (1
8) is equipped with collars (1?a) and (17b) on the inner and outer diameter parts, and a rubber bush (17) with rubber (17c) sewn in between is fitted around the support shaft (13) and pivoted. The rubber bush (17) applies a preload to the link (15) counterclockwise in FIG.
15) extends diagonally upward and backward in a substantially dogleg shape in the embodiment, and a collar (18) is horizontally suspended between the upper parts, while a power unit (19) consisting of an engine, a transmission case, etc.
Inner and outer diameter portions (20a) are provided in the left and right through holes (19b) provided in the boss portions (19a) that protrude left and right at the front of the.

(20b) Fit the rubber bushing (20) with the rubber (20c) baked and interposed between the rubber bushings (20b).
The bolt forming the support shaft (21) between the inner diameter parts of the collar (
18) as if inserted horizontally, the front part of the power unit is pivotally connected between the upper parts of the links (15), and the rubber bushes (2
0) is a power unit of 0 or more which gives a preload in the counterclockwise direction in Fig. 2. The rear side of (19) supports a rear wheel (22) which is a driving wheel, and the power unit (19)
) A rear cushion unit is interposed between the rear part of the rear frame 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 (20) is extended forward at the middle part of this. Stopper rubbers (25) and (2B) are protruding from the top and bottom, and the rubber (25) is attached to the stopper stay (12), and the rubber (25) is attached to the stopper stay (12).
2B) are each opposed to the stopper part (11), and the rubber (25
) and (2B), the stoppers (12) and (11) are offset to the left and right, and the stoppers (12) and (11) are offset to the left and right in consideration of the attachment of the rubber.

Next, to explain its function and effect in detail, the vibration of the engine that makes up the power unit is caused by the lower support shaft (13) of the link (!5).
Engine vibrations are absorbed by the rocking motion using the fulcrums as the fulcrums, and engine vibrations are also absorbed by the rubber bushings interposed at the upper and lower fulcrums, blocking and suppressing the propagation of vibrations to the frame side. In the embodiment, the link (15) is tilted diagonally in the vertical direction, so even if the link length is increased, the power unit does not move rearward due to the layout. 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 links longer.Also, since the front part of the power unit is supported by the upper part of the links, the minimum ground clearance of the power unit can be maintained high, and the links do not hang down. Since it is not 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, and in particular, by arranging a link below the front of the engine, it also functions as an engine guard. The reaction force from the road surface that acts from the rear wheel during driving, the impact, and the reaction force from the rear cushion unit are caused by the swinging of the upper fulcrum (21) of Power Units (19) and the swinging from the lower fulcrum of the link (!5). It is absorbed by the combined movement of the body.

For vibrations and shocks on the power unit side, use the link (15) as the second
The movement is made to swing back and forth around the lower fulcrum (13) in the figure, but the link (15) has a stop rubber (
25) and (2B) are arranged above and below, and the movement of the link causes the stop rubbers (25) and (213) to collide with the upper or lower stoppers (12) and (11), and the rubber (25)
This is absorbed by the elastic deformation of , (2B), and the link (15)
This part absorbs the impact caused by the clockwise and counterclockwise swings of the

In addition, since the stopper rubbers (25) and (21+) are arranged offset to the left and right on both sides of the link (15), the installation of the stopper rubbers (25) and (2B) can be done easily and quickly. .

Furthermore, depending on the settings of the stopper rubbers (25), (2B), the stopper part (11), the stopper stay (12), etc., the compression action of the stopper rubbers (25), (2B) may be effective against vibrations of the engine itself. , power unit (1
9) Vibration due to its own rocking (vibration generated due to changes in driving force when the vehicle stops oscillating) can be effectively absorbed by the action of the stop rubber (25) and (2B) in the shear direction. becomes.

(Effects of the Invention) As is clear from the above description, the power unit suspension system according to the present invention suppresses the propagation of vibrations and shocks to the vehicle body side, and also prevents the impact from hitting the links. # and furthermore, such bullets

[Brief explanation of the drawing]

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) and (21) are upper and lower support shafts, (L3) is a power unit, and (25) and (2B) are stopper levers.

Claims (1)

[Scope of Claims] A suspension system for a power unit comprising a power unit including an engine, a transmission case, a drive wheel, etc., a link connecting the vehicle body and the power unit, and a shock absorber interposed between the vehicle body and the power unit. The front end of the link is pivotally supported on the vehicle body side, and the rear end is pivotally supported on the power unit side, and a stay extending in a direction intersecting the longitudinal direction of the link is provided at an intermediate portion of the front and rear shaft support portions of the link. , an elastic body is provided between the stay and the vehicle body side in a direction that restricts the swinging of the link, and the elastic bodies are arranged offset from each other on both sides of the stay in the swinging direction. Suspension system.