JPH0613310B2 - Front fork mounting structure - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a structure for mounting a front fork used in a motorcycle or the like on a vehicle body.

(Prior Art) For example, in a motorcycle, as shown in FIGS. 4 and 5, the inner tube (5) is placed inside the outer tube (51).
When mounting the inverted front fork (50) in which 2) is slidably fitted to the vehicle body, insert the steering stem (not shown) into the through hole (53b) of the bracket (53) having the slot (53a). Attach to the vehicle body, insert the front fork (50) into the mounting hole (53c) of this bracket (53), and use the bolts (54) and nuts (55) to attach the flange (5) of the bracket (53).
Tighten 3d) and (53e) to fix the front fork (50).

(Problems to be solved by the invention) By the way, a front fork in which an inner tube is slidably fitted in an outer tube is provided between the outer tube and the inner tube in order to smooth the sliding therebetween. Interpose a slide bearing.

In this case, in order to reduce the friction coefficient of the inner tube against twisting and to perform the vertical movement reliably, it is better that the distance between the two slide bearings interposed between the outer tube and the inner tube is as wide as possible,
It is desirable that the inner tube is attached to the outer peripheral surface of the upper end portion and the outer tube to the inner peripheral surface of the lower end portion.

However, in the conventional mounting structure described above, the outer tube (51) is fixed because the flange portions (53c) and (53d) of the bracket (53) are tightened with the bolts (54) and the nuts (55). In many cases, the portion tightened by the bracket (53) and its peripheral portion are deformed inward.

Therefore, as shown in FIG. 4, the conventional front fork (5
(0) has the slide bearings (56), (57) fitted below the lower end of the inner peripheral surface of the outer tube (51) and the part that secures the bracket (53), respectively. There is a case where the rigidity is not sufficient and the sliding is not smooth.

(Means for Solving Problems) In order to solve the above problems, the present invention integrally forms an attachment portion in the middle portion of the outer tube, and attaches this attachment portion to the bracket from the side of the vehicle body via a bolt. In addition to the connection, the mounting portion and the bracket are fitted in the recess and protrusion.

(Operation) The attachment portion is connected to the bracket in a state where the inner diameter of the outer tube is not affected, and the bracket and the outer tube are fitted in a concavo-convex manner, so that the positioning is accurately performed.

(Examples) Examples of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a half sectional view showing a mounting structure of a front fork to a vehicle body according to the present invention, and FIG. 2 is a transverse sectional view of FIG.
FIG. 3 is a front view of FIG. 2 seen from the direction of arrow III.

The front fork (1) has an inner tube (3) slidably fitted in the outer tube (2), and is fitted to the outer peripheral surface of the upper end of the inner tube (3) and the lower end of the outer tube (2). Slide bearings (4) and (5) are fitted on the inner peripheral surfaces, respectively. An upper bracket (6) is attached to the outer surface of the upper end of the outer tube (2), and a joint metal (7) is attached to the lower end of the inner tube (3).

In addition, a mounting portion (9) to the lower bracket (10) is integrally formed at approximately the center of the outer tube (2), and the bracket (10) and the mounting portion (9) are fitted to each other. To form a convex portion (9a) and a concave portion (10a) for the bracket (1
(0) has an overhang part (10b) that engages with the upper end surface of the half body (9).
Flanges (9b) and (9c) are formed on the mounting part (9) to form two bolt holes (9d) and (9c) on each flange part (9b) and (9c).
e) is drilled, and further, the bracket (10) is formed with screw holes (10b), (10c) corresponding to the bolt holes (9d), (9e) of the mounting portion (9).

Therefore, when attaching the front fork (1) to the vehicle body, the attachment part (9) formed on the outer tube (2)
The convex portion (9a) is fitted into the other concave portion (10a) of the bracket (10) attached to the vehicle body.

Then, bolt the bolt holes (9d) and (9e) on the bracket (10).
Tighten through (11) and attach the mounting (9) to the bracket (1
The front fork (1) is fixed to the vehicle body by fixing it to (0).

In this case, the outer tube (2) of the front fork (1)
Is not deformed by being tightened by the bracket (10), and slide bearings (4) and (5) are attached to the outer peripheral surface of the upper end of the inner tube (3) and the inner peripheral surface of the lower end of the outer tube (2), respectively. Even if is fitted, the inner tube (3) is not obstructed from sliding and locked, and the vertical movement does not slow down.

Further, even when a force (F) in the direction of the arrow in FIG. 1 is applied to the front fork (1), due to the contact between the overhang portion (10b) of the bracket (10) and the mounting portion (9), Mounting part
There is no displacement between the bracket (10) and the bracket (9).

As described above, according to the present invention, when the outer tube of the front fork is attached to the bracket on the vehicle body side, the inner diameter of the outer tube does not change. Two slide bearings interposed between the inner tube and the outer tube can be attached to the outer surface of the inner tube and the inner tube of the outer tube. Can be done smoothly.

[Brief description of drawings]

FIG. 1 is a half sectional view showing a mounting structure of a front fork according to the invention to a vehicle body, FIG. 2 is a lateral sectional view of FIG. 1, and FIG. 3 is a front view of FIG. 2 seen from an arrow III direction. FIGS. 4 and 5 are half sectional views showing a conventional mounting structure of a front fork to a vehicle body, and FIG. 5 is a lateral half sectional view of FIG. In the drawing, (1) is a front fork, (2) is an outer tube, (3) is an inner tube, (6) and (7) are slide bearings, (9) is a mounting part, (10) is a bracket, and (9a ) Is a convex portion, (10a) is a concave portion, and (11) is a bolt.

Claims (1)

[Claims] 1. In a structure in which a front fork having an inner tube slidably fitted in an outer tube is mounted on a vehicle body via a bracket, a mounting portion for the bracket is integrally provided at an intermediate portion of the outer tube. The mounting portion is joined to the bracket through a bolt in a state of being abutted from the side of the vehicle body, and a convex portion or a concave portion that engages with the concave portion or the convex portion of the bracket is formed in a part of the mounting portion. Front fork mounting structure to the vehicle body, which is characterized by