JPS6264663A - Master cylinder - Google Patents

Abstract

PURPOSE:To obtain a master cylinder with various pipe joint position at low cost, by forming a cylinder main body into a square shape substantially throughout its total length from a steel pipe and opening a port and welding a pipe joint on its outside surface. CONSTITUTION:A cylinder main body 1 is formed into a square column with multi-surface substantially over its total length. A port 10 is opened at any one of the surfaces A1-A8 and a pipe joint 4 is welded on the surface. Therefore, many kinds of master cylinders with the pipe joint 4 located at a different position can be produced at low cost using the master cylinder main body 1 and the pipe joint 4 as common parts. In addition, the port 10 and the pipe joint 4 can be easily standardized and the port can be drilled accurately.

Description

Detailed Description of the Invention A0 Object of the Invention (1) Industrial Application Field The invention is directed to a master cylinder, especially a cylinder, for generating full hydraulic pressure to operate a hydraulic clutch, brake, etc. of a vehicle. The present invention relates to an improvement of a master cylinder in which a pipe joint is provided protruding from the outer surface of a cylinder body having a hole, and a port tf is bored in the side wall of the cylinder body to communicate the pipe joint and the cylinder hole with each other.

(2) Conventional technology Conventionally, such a master cylinder has been used, for example, in
As disclosed in Japanese Patent No. 16754.6, the cylinder body and the pipe joint are integrally formed by casting.

(3) Problems to be solved by the invention As mentioned above, in a master cylinder in which the cylinder body and the pipe joint are integrally molded by casting, it is difficult to manufacture different types of master cylinders in which the position of the pipe joint is different. However, each time a mold with a different cavity shape must be prepared, the manufacturing cost is high (therefore, there is a limit to the ability to reduce costs).

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a master cylinder that can be manufactured at low cost even when the positions of the pipe joints are different.

B8 Structure of the invention (1) Means for solving the problem In order to achieve the above object, the present invention forms a cylinder body from a steel pipe into a prismatic shape over almost the entire length, and a flat surface on the outside of the cylinder body. All features are that the boat is opened and the pipe joints are welded.

(2) Effects According to the above configuration, by using the cylinder body and the pipe joint as common parts, it is possible to manufacture many types of master cylinders with different positions of the pipe joint at low cost.

Moreover, since the cylinder body is a prism, that is, a polyhedron,
It is easy to standardize the positions of boats and pipe joints.

In addition, since the boat on the side wall of the cylinder body can be drilled from the flat surface on the outside of the side wall, the tip of the drill does not slip as when drilling on a cylindrical surface, and the hole can be drilled precisely in a fixed position. can do.

Furthermore, since the cylinder body and the pipe joint are welded on a plane, welding can be performed reliably even in any rotational position of the pipe joint.

(3) Examples Examples of the present invention will be explained below with reference to the drawings.
First, in FIG. 1 showing a first embodiment, a master cylinder M includes a cylinder body 1 having a cylinder hole 1a', and an end wall member 2 welded to the front open end of this cylinder body 1.
A connector 3 as a pipe joint welded to the front surface of the end wall member 2 of and , a union 4 as another pipe joint welded to the upper surface of the cylinder body 1, and a union 4 slidably fitted into the cylinder hole 1a. A piston 6 that defines a hydraulic chamber 5 between it and the end wall member 2, a return spring γ that urges the piston 6 in its backward direction, and a return spring γ that urges the piston 6 in the backward and forward movement of the end wall member 2.
An outlet boat 10 is bored in the upper wall of the cylinder body 1 to communicate between the hydraulic chamber 5 and the union 4. .

An oil guide pipe 12 connected to an oil tank 11 is connected to the connector 3, and a hydraulic conduit 14 connected to a hydraulic actuator, for example, a hydraulic clutch 13, is connected to the union 4.

A bushing rod 16 that is pushed by an operating pedal 15 is connected to the rear end of the piston 6, and a cap 17 that restricts the backward limit of the bushing rod 16 is fitted and locked to the rear end of the cylinder body 1. Ru.

The valve device 9 includes a cup-shaped valve housing 18 whose open end abuts against the end wall member 2 that is slid into the cylinder hole 1a, and a valve 19 that is housed in the pulp housing 18 and opens and closes the inlet boat 8. This pulp 1 inside the valve housing 18! The valve housing 18 includes a closing spring 20 that biases the l-input robot 8 in the closing direction, and the valve housing 18 is provided with a notch 21 that communicates the inside thereof with the hydraulic chamber 5. The valve 19 is integrally equipped with a valve stem 22 that extends rearward through the end wall of the valve housing 18, and has an enlarged portion 2 formed at the rear i of the pulp stem 22.
2a is slid into a blind hole 23 provided at the center of the piston 6, and a hat-shaped retainer 24 is fitted and engaged with the front end of the piston 6 to prevent the enlarged portion 22a from coming out of the blind hole 23. will be stopped.

There are a pair of front and rear mounting brackets on the bottom side of the cylinder body 1).
25 and 25 are connected to each other, and the master cylinder M is attached to the automobile body by fixing them to a support bracket 26 protruding from the automobile body with a pole 27 and 27.

Therefore, when the operating pedal 15 is inactive, the piston 6
It is held in the retracted position by the return spring T, and the valve stem 22 is pulled rearward to open the valve 19. Therefore, the hydraulic chamber 5 has an inlet port 8 and an outlet port 1
10, the hydraulic clutch 13 releases its hydraulic pressure to the oil tank 11 through the hydraulic chamber 5, and is in a connected state.

When the piston 6 is moved forward against the force of the return spring 7 by pressing the operating pedal 15, the pulp 19 first closes the inlet boat 8 with the elastic force of the closing spring 20.
Thereafter, the hydraulic pressure generated in the hydraulic chamber 5 as the piston 6 moves forward is outputted from the outlet port 110 to the clutch 13, whereby the clutch 13 can be brought into the disconnected state.

In such a master cylinder M, the cylinder body 1
By drawing a steel pipe, the cross-section polygon,
In the illustrated example, it is formed into an octagonal prism (see FIG. 2), and after drawing, a grooved cylindrical surface 28 is provided on the outer periphery of the rear end portion of the cylinder body 1 for fitting and locking with the cap 17. is removed.

Eight planes constituting the outer peripheral surface of the cylinder body 1 are
As shown in the figure, the planes will be referred to as the first to eighth planes A, -A8 in clockwise order from the top, and the exit bow 110 is drilled from the 1,000th plane A by drilling. Therefore, during drilling, the cutting edge of the drill does not slip, and the exit bow 10 can be accurately drilled at a fixed position on the first plane A.

Further, the union 4 is projection welded to the 1,000th surface A1. This projection welding is performed with the 1,000th surface A1 being crimped onto an annular projection 4a' integrally formed on the lower surface of the union 4, as shown in FIG. As described above, since the welding surfaces of the cylinder body 1 and the union 4 are flat, both the cylinder body 1 and the union 4 can be easily and reliably welded without considering the position around the axis of the union 4 equally.

The end wall member 2 is fitted and welded to the front end of the cylinder body 1, and the connector 3 is projection welded to the end wall member 2.

The mounting bracket 25 has a bolt hole 25a' in the center.
The cylinder body 1 is formed into an Ω-shape so as to hold the cylinder body 1, and both ends thereof are spot welded to the 5000th surface A of the cylinder body 1. Therefore, in this case as well, since welding is performed between flat surfaces, the welding can be performed easily and reliably.

4 to 6 each show another embodiment of the present invention, in which a cylinder body 1, a connector 3, a union 4
The mounting brackets 25 and 25 are the same as those in the previous embodiment, but their welding positions are different.

In addition, as in the embodiment shown in FIG.
2, it goes without saying that the front open end of the cylinder body 1 should be closed by an end wall member of the port.

FIG. 7 shows an embodiment in which the present invention is applied to a side port type master cylinder M, and the first plane A shows an embodiment in which the present invention is applied to a side port type master cylinder M.

, a relief port 30 and a supply port 31 are bored in the cylinder body 1, and these ports 30
, 31 are projection welded, and a union 4 is fully fitted and welded to the front open end of the cylinder body 1.

FIG. 8 shows a modification of the mounting bracket. That is, the mounting bracket 125 is attached to the first to
The intermediate portion 125at is adapted to fit the fifth plane A, ~A,
The intermediate portion 125a is spot welded to the first and fifth planes AI+A5, and the flanges 125h, 125. 6 is fixed to the support bracket 126 of the vehicle body by pins 32 and 32. Using such a mounting bracket 125 not only allows for more welding points with the cylinder body 1, but also allows contact with the cylinder body 1 on multiple surfaces, increasing the bonding strength between the mounting bracket 125 and the cylinder body 1. can be increased.

Effects of the C0 Invention As described above, according to the present invention, the cylinder body is formed into a prismatic shape over almost the entire length from the steel pipe, and a hole is opened on the outside plane of the cylinder body, and the pipe joint is welded. By using the cylinder body and the pipe joint as common parts, many types of master cylinders with different positions of the pipe joint can be manufactured at low cost.

In particular, it is easy to standardize the positions of the boat and pipe joint on multiple planes around the cylinder body's outer circumference, the boat can be drilled accurately, and the welding between the cylinder body and the 1' joint is easy. By being able to reliably perform the rotation at any rotational position of the joint, etc., it can greatly contribute to not only lowering the cost of many types of master cylinders but also increasing their accuracy.

[Brief explanation of drawings]

The drawings show embodiments of the present invention, and FIG. 1 is a longitudinal cross-sectional side view of the master cylinder of the first embodiment, and FIG.
- ■ Line sectional view, Figure 3 is an explanatory diagram of the state before projection welding of the cylinder body and the union, which is a pipe joint, Figure 4
5 and 5 are side views of the master cylinders of the second and third embodiments, FIG. 6 is a cross-sectional view of the master cylinder of the fourth embodiment, and FIG. 7 is a cross-sectional view of the master cylinder of the fifth embodiment. FIG. 8 is a cross-sectional view of the master cylinder of the sixth embodiment. A, ~A,... 1st to 8th plane, M... Master cylinder, 1... Cylinder body, 1a... Cylinder hole, 2...
・End wall member, 3... Connector as a pipe joint, 4...
・Union as a pipe joint, 8...Inlet port, 10
... Outlet boat, 11 ... Oil tank, 12 ... Oil guide pipe, 13 ... Hydraulic clutch, 14 ... Hydraulic conduit, 25
, 125...Mounting bracket, 30...Relief boat, 31...Supply boat

Claims (1)

[Claims] In a master cylinder in which a pipe joint is provided protruding from the outer surface of a cylinder body having a cylinder hole, and a port is bored in the side wall of the cylinder body to communicate the pipe joint and the cylinder hole with each other, the cylinder body is made from a steel pipe. 1. A master cylinder characterized in that it is formed into a prismatic shape over substantially its entire length, has a port opened in a plane on the outside of the cylinder body, and has a pipe joint welded to it.