JPS62181988A - Front-wheel suspension system for motorcycle - 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 front wheel suspension system for motorcycles (including tricycles).

(Prior Art) A leading type front wheel suspension system in which the front wheels are cantilever-supported via a swing arm extending forward from the intermediate portion of the vehicle has been disclosed in Japanese Patent Publication No. 58-49435. For strength reasons, the swing arm has a main arm and an auxiliary arm formed into a substantially Y-shape in plan view, and the shock absorber is disposed between the upper surface of the main arm of the swing arm and the vehicle side.

(Problems to be Solved by the Invention) Therefore, in the conventional structure, the space for arranging the shock absorber is limited to a limited space above the swing arm and between the vehicle side and the placement of the shock absorber is restricted.

It was difficult to ensure a large stroke for the shock absorber. In addition, in addition to the shock absorber, front wheel suspension system members such as the upper swing arm and front wheel steering system members such as tie rods are arranged above the swing arm, so front wheel suspension system members and front wheel steering system members are arranged. When doing so, there were problems such as these members interfering with each other and being subject to restrictions.

The present invention has been devised to solve the above-mentioned problems, and an object of the present invention is to improve the riding comfort of a motorcycle by ensuring a large stroke of the shock absorber, and to improve the riding comfort of a motorcycle. An object of the present invention is to provide a front wheel suspension system for a motorcycle, which is advantageous in arranging a front wheel steering system member.

(Means for Solving the Problems) In order to achieve the above object, the present invention includes a swing arm (33), a main arm (33A) disposed on the side of the front wheel (3), and a main arm (33A) disposed on the side of the front wheel (3). The swing arm (33) is formed into a substantially Y-shape in plan view with an auxiliary arm (33B) extending from the longitudinal center portion of ) toward the front wheel (3) in the vehicle width direction and having a rearwardly curved tip. In the space (73) defined by the main arm (33A) and the auxiliary arm (33B),
A shock absorber (41) is disposed on the main arm (33A) side of the vehicle width center (69) so as to be inserted therethrough substantially in the vertical direction.

(Function) Since the shock absorber (41) can be disposed using the space above and below the swing arm (33), a large stroke of the shock absorber (41) can be ensured, improving the riding comfort of the motorcycle (1). can be improved.

Also, since the upper part of the buffer (41) can be lowered,
The other swing arm (31) and rod (147)'
J can be arranged without interfering with the shock absorber (41), which is advantageous in arranging front wheel suspension system members and front wheel steering system members.

(Embodiment) A preferred embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic side view of the motorcycle, FIG. 2 is a schematic plan view thereof, and FIG. 3 is a sectional view taken along the line m--■ in FIG. 1.

(1) is the motorcycle, (3) is the front wheel, (5) is the handle, (7) is the engine, (9) is the rear wheel, (11) is the seat, and the body frame (13) of the motorcycle (1). is composed of an upper frame (15) and a lower frame (17).

The lower frame (17) is left and right lower frame members (17A) arranged on the left and right sides of the engine (7), respectively.

(17B), and the frame member (17B) shown below is ffJ.
A).

(17B) are front and rear pieces (171), (172), and upper and lower pieces (173), respectively.

(174), each frame member (1
7A), (17B) mounting part (19), ..., engine side mounting part (20), ..., Pol) (21
) to the left and right sides of the engine (7) to the lower frame members (1?A) and (17B).

The engine (7) is a V-type four-cylinder engine, with four cylinders (7A), (7A), (7B), (7
B), and carburetors (23), etc. are arranged in the V-bank space between the cylinders (7A) and (7B), and the carburetors (23), .
An air cleaner (25) is disposed above the air cleaner (23).

The axle (27) of the front wheel (3) has a knuckle arm (
28), and the front wheel (3) is suspended in a leading manner. That is, the front wheel (3) is suspended by the upper and lower swing arms (31), (33) installed between the front piece (171) and the knuckle arm (29), and the lower swing arm (33) and the front piece. (171) Link provided between (35)
, (37), and a buffer (41) provided between the front piece (171) and the progressive link mechanism (39).

The front piece (171), the upper and lower swing arms (31)
.

(33), a parallel movement mechanism (43) is configured by the knuckle arm (28), and the knuckle arm (29) is a lower part (29) that supports the axle (27) inside the wheel.
A), an extension part (29B) that extends upward while curving outward from the lower part (2θA), and an upper end ffl ( 29C)
It consists of

The shock absorber (41) connects the upper end mounting portion (191) to the mounting portion (193) of the lower frame member (1?A) with a bolt (19).
5), and attach the lower end to the progressive link mechanism (
3θ) link (35).

Link (35) of the progressive link mechanism (39)
The base (35A) of the lower frame member (17A), (
17B) via a bearing (207).

One end (205A) of the shaft (205) on which the link (35) is pivotally attached is screwed into the bracket (201) of the lower left frame member (17A) via a nut (209). The bracket (203) of the lower frame member (17B) on the right side has a through hole (213) in which a split part (211) is formed, and the other end (205B) of the shaft (205)
) is inserted into the through hole (213), and the bolt (215)
, (215) and the through hole (211) through the split portion (211).
13) and fix the other end (205B) of the shaft (205). This mounting structure of the shaft (205) absorbs assembly errors in the vehicle width direction.

Link (35) of the progressive link mechanism (39)
The tip (35B) is shown in a plan view in FIG. 5 and in a side view of the main part in FIG. )
Pivotally connected via.

The other link (37) constituting the progressive link mechanism (39) has a bifurcated base (37) as shown in FIG.
A) to the bracket part (22) of the lower swing arm (33).
? ) is pivotally connected to the bolt (229) via a bearing (231), and the pin portion (37B) at the tip is attached to the intermediate boss Fl! of the link (35) via a bearing (233). (35G).

The upper swing arm (31) has a roughly V-shape in plan view, and is connected to the left and right lower frame members (31A) via bolts (45) and bearings (47), respectively. 1?A), (17B), and the front end (
31B) is coupled to the upper end (29G) of the knuckle arm (29) via a support shaft (49) extending in the left-right direction and a support shaft (51) extending diagonally in the vertical direction.

The lower swing arm (33) includes a main arm (33A) arranged on the side of the front wheel (3) and a main arm (33A).
It is composed of an auxiliary arm (33B) branching from the auxiliary arm (33B), and has a substantially Y-shape in plan view.

The auxiliary arm (33B) extends from the longitudinal center of the main arm (33A) toward the front wheel (13) in the vehicle width direction, and has a lateral portion (33B+) located behind the front wheel (13) and a lateral portion ( 33B+) and a leg portion (33B2) extending rearward from the outer end of the leg portion (33B+) via a curved portion (33B3).

The main arm (33A) has a leg part (33A,) extending rearward from a connecting part (33A,) to which the auxiliary arm (33B) is connected.
33A2) and the front wheel (
3) An arm portion (33A3) extending to the side.

As shown in FIG. 2, the lower swing arm (33)
A bent portion (32) is formed in a portion near the front of the connecting portion (33A2) when viewed from the side of the vehicle, so that the bent portion (32) is formed in a box-shaped shape when viewed from the side.

The leg portion (33A2) of the main arm (33A) has a support shaft (55) attached to the forked portion (53) of the lower frame member (1?A).
, are connected in a double-sided manner via a bearing (57), and the other leg (33B2) is connected to the mounting portion (58) of the 5 lower frame member (17B) via a support shaft (81) and a bearing (63). It is coupled in a cantilevered manner from the inside of the lower frame member (17B).

The front end of the arm portion (33A3) is coupled to the lower part (29A) of the knuckle arm (2θ) via a support shaft (65) extending in the left-right direction and a support shaft (87) extending diagonally in the vertical direction, When viewed from above as shown in FIG. 2, the support shaft (51
), (57) are the support shafts (51) located on the vehicle width center line (69) and viewed from the side as shown in FIG.

(57) are arranged on the same straight line (71) with their axes aligned.

In the space (73) defined by the two leg parts (33A2), (33B2) and the side part (33B+), a shock absorber (41) and an exhaust pipe of the front cylinder (7A), (7A) are provided. (
73), place (73) and! The shock absorber (41) is deviated closer to the arm portion (33C) than the vehicle width center line (B8) in accordance with the distribution of the load that the lower swing arm (3a) receives. In the embodiment, as shown in FIG. 3, the front wheel (3) is deviated outward by a distance (e+) from the side surface (3A) of the vehicle width, and the axis (241) of the shock absorber (41) is aligned with the base of the lower swing arm ( 3
3A) (7) Distance 1Ill from center (243) (B2)
The vehicle width is shifted inward.

The exhaust pipes (73), (73) are made to extend rearward after passing through the space (73), and have a collection chamber (75) in the middle part.
A muffler (77) is installed at the rear end, and the exhaust pipes (7B) and (7B) of the rear cylinder (7B) are installed in the collecting chamber (75).
79) and (79) are connected.

The axle (81) of the rear wheel (9) is connected to the rear fork (8
3), and the rear wheel (8) is driven by a chain (84). The rear wheel (9) is suspended by the rear fork (83),
A progressive link mechanism (89) consisting of links (B5) and (87) is provided between the rear fork (83) and the lower frame (17), and a progressive link mechanism (89) is provided between the lower frame (17) and the progressive link mechanism (89). This is done using a buffer (B1).

As shown in FIG. 2 of the rear fork (83), the front fork (83A), (83A) and the engineer's fork (83B)
, (83B), and a front fork (83A), (83
A) is pivotally attached to the inner surfaces of the lower frame members (17A) and (17B) via support shafts (93), respectively, and the technician's section (
The rear wheel (9) is arranged between (83B) and (83B).

The upper frame (15) is disposed above the lower frame (17), and the upper frame (15) includes a frame member (101) having a U-shaped cross section and extending in the front-rear direction; ) and a plurality of cross members (103), . . . , which are welded to the upper surface of the cross members (103) and extend in the left-right direction, and a cross section which is welded to the left and right ends of the cross members (103), . Curved frame member (1
05) and (105).

A pair of left and right stays (107) extend from the front and middle portions of the frame member (101) having a U-shaped cross section.

(107), (109), (10,9) are installed vertically, and each stay (107).

(109) The lower end cylinder part (10) is connected to the front and rear end stays of the lower frame (17) <113), (113), (115),
(115) and anti-vibration rubber (117) as shown in Figure 4.
, pole) (119), and are detachably and elastically connected via a nut (121). Furthermore, frame members (101
) from the rear of the stay (123), (125) with tf<
A muffler (77) is supported at the lower ends of the stays (123) and (125), and a rear fender (127) is provided.

A bracket part (129) for attaching the handle is integrally formed on the front part of the ball frame (15).
A cylindrical member (135) is attached to 129) via a long groove (131) and a bolt (133) so as to be adjustable in tilt. The steering stem (137) is rotatably supported by the cylindrical member (135), and the bar handle (5) is mounted on the steering stem (13?).

Then, connect the lower end of the steering stem (137) and the knuckle arm (29) to the steering stem (13?).
Arm (141) protruding from the lower end, lower frame (1
7), an arm (143) pivotally connected to both the arms (1
Rod (145) connecting between 41) and (143,)
, the arm (143) and the knuckle arm (29) are connected via a connecting rod (147), etc., and the handle (5
) operation to steer the front wheels (3).

A bracket (1) is attached to the front end of the bracket part (129).
49), a meter unit (151) is installed.

The frame members (105), (10
5) Above is a dummy tank (153), sea) (11
) is placed through a vibration-proof rubber (155), an air cleaner (25) is placed in a downwardly open recess (15?) provided in the dummy tank (153), and the lid (157a) is opened. Perform maintenance work.

The vehicle body is covered with a front fender (159A), a rear fender (159B), and a cowling (180).
81) is the radiator, (183) is the oil pan, (1B
5) indicates a side stand that is pivotally supported (185a) on the lower frame (7), and (tea) indicates a main step.

The present embodiment is configured as described above, and the shock absorber (41) is inserted into the space (73) defined by the main arm (33A) and the auxiliary arm (33B) of the lower swing arm (33). Since the shock absorber (41) is attached to the lower swing arm (3),
3) The shock absorber (41) can be disposed using the upper and lower spaces, thereby ensuring a large stroke of the shock absorber (41) and improving the riding comfort of the motorcycle.

In addition, the upper part of the shock absorber (41) can be lowered, and as in the embodiment, the shock absorber (41) can be placed below the upper swing arm (31).
1), the location of the shock absorber is not limited to above the upper swing arm as in the past, and therefore the shock absorber (4
1) It is also possible to arrange the front wheel suspension system members such as the shock absorber (41) and the upper swing arm (31) at a desired location and at a desired angle without interfering with the upper swing arm (31). This will be advantageous when setting up. In addition, front wheel steering system members such as the rod (147) can be disposed above the shock absorber (41) without interfering with the shock absorber (41) as in the embodiment, and it is also possible to arrange the front wheel steering system members above the shock absorber (41). It will be advantageous.

In addition, since the mounting position of the shock absorber (41) is located further outward in the width of the vehicle than the front wheels (3), the wind is constantly flowing through the shock absorber (41).
41), the thermal influence of the engine (7) on the shock absorber (41) can be reduced and the durability of the shock absorber (41) can be increased.

In the embodiment, a case has been described in which the lower part of the shock absorber (41) is connected to the link (35) of the progressive link mechanism (39) below the lower swing arm (33). The lower part is, for example, the lower swing arm (33)
It may be connected to a bracket or the like provided with a claw, and directly connected to the lower swing arm (33).

(Effects of the Invention) As is clear from the above description, according to the present invention, it is possible to ensure a large stroke of the shock absorber in a leading type front wheel suspension system, thereby improving the riding comfort of a motorcycle. This is advantageous in arranging front wheel suspension system members and front wheel steering system members.

[Brief explanation of drawings]

Fig. 1 is a schematic side view of the motorcycle, Fig. 2 is a schematic plan view thereof, Fig. 3 is a sectional view taken along the line ■-■ in Fig. 1, and Fig. 4 is a sectional view of the joint between the upper frame and the lower frame. , FIG. 5 is a sectional plan view of the main part of the progressive link mechanism, and FIG. 6 is a side view of the same. In addition, (1) in the drawing is a motorcycle, (3) is a front wheel, and (5)
is the steering wheel, (7) is the engine, (8) is the rear wheel, (11)
) is the seat, (13) is the body frame, (31) is the upper swing arm, [33] is the lower swing arm, (4])
is a buffer, and (73) is a space.

Claims (2)

[Claims] (1) In a vehicle in which a front wheel is supported in a cantilevered manner via a swing arm extending forward from an intermediate portion of the vehicle, and a shock absorber is disposed between the swing arm and the vehicle, the swing arm is connected to the front wheel. The main arm is arranged on the side, and the auxiliary arm extends from the longitudinal center of the main arm toward the front wheels in the vehicle width direction and has a rearwardly curved tip, forming a substantially Y-shape in plan view. The motorcycle is characterized in that the shock absorber is inserted and disposed in a substantially vertical direction closer to the main arm than the center of the vehicle width within a space defined by the main arm and the auxiliary arm of the swing arm. Front wheel suspension. (2) The front wheel suspension system for a motorcycle according to claim 1, wherein the shock absorber is disposed at a location further outward in the vehicle width than the front wheel.