JPH011680A - Mounting structure of master cylinder for rear brake device - 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 mounting structure for a master cylinder for a hydraulic rear brake device provided in a motorcycle.

[Conventional technology]

In a hydraulic type rear brake device, a master cylinder is generally attached to the vicinity of the lower rear side of the seat pillar tube via a bracket. The hydraulic pressure generated in the master cylinder is guided to the rear wheel braking member through a brake hose connected in a space between the bracket and the backstay.

[Problem that the invention seeks to solve]

However, with this type of structure, the connection between the master cylinder and the brake hose is not protected in any way, so when driving over rough terrain, stones thrown up by the wheels or rocks protruding from the road surface may be exposed. could come into contact with the connection and damage the connection.

Therefore, in order to solve this problem, it is possible to increase the strength of the connection part or to cover the outside of the connection part with a protective member. However, in the former case, since the connection structure is a structure in which the connection is made via a thin pipe caulked and fixed to the end of the brake hose, there is a limit to increasing the strength of the connection part. On the other hand, in the latter case, the protection member protrudes to the side of the vehicle body and comes into contact with the driver's feet.

[Means for solving problems]

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a mounting structure for a master cylinder for a rear brake device that can prevent damage to the connecting portion between the master cylinder and the brake hose. In the master cylinder mounting structure according to the present invention, the bracket for mounting the master cylinder is formed into a U-shaped cross section, the backstay is fixedly supported by the bracket, and the backstay is fixedly supported in the space surrounded on all sides by the bracket and the seat pillar tube. , showing the connection between the master cylinder and brake hose.

[Effect]

In the present invention, since the connection part is surrounded by a bracket and a seat pillar tube, rocks, etc. are prevented from coming into contact with the connection part.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a side view showing the main parts of a motorcycle in which the mounting structure for a master cylinder for a rear brake device according to the present invention is implemented, FIG. 2 is a sectional view taken along the line ■-■ in FIG. 1, and FIG. FIG. 1 is a side view showing the entire motorcycle. The body frame of the motorcycle, indicated by reference numeral 1 in FIG. 3, houses a head pipe 2, a tank rail 4 extending rearward from the head vibe 2 and supporting a fuel tank 3, and an engine 5 between the tank rail 4. a down tube 6 extending from the head vibe 2 to the rear end, a pair of left and right seat pillar tubes 7 connected to the rear end of the tank rail 4, and a down tube 6 extending from the upper end of the seat pillar tube 7 to the rear end. A seat rail 9 extending to support the seat 8, and a back stay 1 supporting the rear part of the seat rail 9 from below.
It consists of 0, etc. Reference numeral 11 denotes a pair of left and right rear arms that are pivotably pivoted up and down on a pivot 12 extending between the left and right seat pillar tubes 7, and suspend a rear wheel 13. 14 is a footrest supported at the lower part of the seat pillar tube 7 on the right side of the vehicle body so as to be freely foldable.

A rear brake device 21 includes a master cylinder 22, a brake pedal 23 that operates the master cylinder 22, a caliper 25 that brakes a disc plate 24 that rotates integrally with the rear wheel 13, and the like. 26 is a steel plate bracket fixed to the rear side of the seat pillar tube 7 on the right side of the vehicle body, the upper part 26a is formed in a U-shaped cross section opening forward, and the lower part 26b is formed in a flat plate shape extending in the front-rear direction. has been done. That is, the bracket 26 is made of a plate member having an upper part 26a extending upwardly toward the rear of the vehicle body, and this upper part 26a is bent to the left of the vehicle body above the rear end of the lower part 26b, and then folded back toward the front of the vehicle body. It is formed in a U-shape. and top 2
The backstay 10 is fixedly supported on the back side of 6a.

Also, the master cylinder 22 is attached to the lower part 26b.
It is attached with 27,27. The brake pedal 2
3 is formed in a shape that straddles the footrest 14, and is pivotably attached to the seat pillar tube 7 below the bracket 26. And at the rear is the master cylinder 2.
An arm 23a is rotatably connected to the second piston rod 22a, and a pedal portion 23b is provided at the front end.

31 is the brake hose, 32 is this brake hose 31
This is a connection joint for connecting the master cylinder 22 to the master cylinder 22. The connection joint 32 has a cylindrical portion 32a through which a connection bolt 33 screwed into the master cylinder 22 passes, and a brake hose 31.
It consists of a pipe part 32b whose end part is caulked and fixed,
The pipe portion 32b extends from the cylindrical portion 32a so that the connection portion with the brake hose 31 faces into a space surrounded on all sides by the bracket 26 and the seat pillar tube 7. The brake hose 31 is bent into an arc shape above this space so as to extend rearward. Further, the brake hose 31 may be bent into a loop shape so as to extend forward from the seat biller tube 7 and then again toward the rear, as shown by the chain line in FIG.

In a brake device in which the master cylinder mounting structure configured as described above is implemented, the brake pedal 2
When the brake hose 3 is lowered, the piston of the master cylinder 22 moves upward, generating hydraulic pressure, and the working fluid flows into the brake hose 3.
Since oil is supplied and pressurized to the cylinder of the caliper 25 through the cylinder 1, the disc plate 24 is braked under pressure.

Further, the connection portion between the brake hose 31 and the master cylinder 22 can be covered with the bracket 26 and the seat pillar tube 7. Therefore, when driving on uneven ground, stones rolled up by the wheels or rocks protruding from the road surface can be prevented from coming into contact with the contact portion, thereby preventing damage to the connection portion.

Moreover, the bracket 26 for attaching the master cylinder 22 can be used as a frame strength member for connecting the seat pillar tube 7 and the ballast 10, and at the same time, the bracket 26 can also be used to protect the connection part, so a separate protection member can be used. Unlike the existing structure, the number of parts does not increase and the vehicle body does not expand in the width direction of the vehicle.

Furthermore, by passing the brake hose 31 between the brackets 26, the brake hose 31 can be
Not only can the brake hose 1 be gently extended without sharply bending it, but also interference with the rear arm 11 can be avoided, making it easier to route the brake hose 31.

〔Effect of the invention〕

As explained above, according to the present invention, the bracket for attaching the master cylinder is formed to have a U-shaped cross section, the backstay is firmly supported by this bracket, and the space surrounded on all sides by the bracket and the seat pillar tube is provided. In addition, since the connection between the master cylinder and the brake hose is exposed, the area around the connection can be covered and protected with a bracket and a seat pillar tube.

Therefore, since the bracket can prevent stones rolled up by the wheels or rocks protruding from the road surface from coming into contact with the connection part while the vehicle is running, it is possible to prevent damage to the connection part. Moreover, the bracket for mounting the master cylinder is not only used to protect the connection part, but also as a frame strength member that connects the seat pillar tube and ballast tie.
Unlike a structure with a separate protection member, the number of parts does not increase and the vehicle body does not expand in the vehicle width direction, and by attaching the master cylinder to the frame, the structure that protects the connection part can be made compact. can.

[Brief explanation of drawings]

FIG. 1 is a side view showing the main parts of a motorcycle in which the mounting structure for a master cylinder for a rear brake device according to the present invention is implemented, FIG. 2 is a sectional view taken along the line nn in FIG. 1, and FIG. FIG. 1 is a side view showing the entire motorcycle. 7... Seat pillar tube, 10... Back stay, 22... Master cylinder, 26... Bracket, 31... Brake hose, 32...
connection fitting. Patent applicant Yamaha Motor Co., Ltd.

Claims (1)

[Claims] A bracket fixed to the rear side of the seat pillar tube to which the master cylinder is attached is formed into a U-shaped cross section that is open to the front. A mounting structure for a master cylinder for a rear brake device, in which the connection part between the master cylinder and the brake hose is exposed in a space surrounded by a rear brake system.