JPH0229021Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a cylinder structure in a hydraulic system of a power steering device.

[Prior art and its problems]

A power steering device in an automobile includes a steering shaft 1 as illustrated in FIG.
A hydraulic cylinder 5 through which the rack rod 3 is inserted is connected to a pinion housing 4 into which a rack rod 3 that meshes with the pinion 2 at the lower end is inserted, and the rack rod 3 is moved by hydraulic pressure during steering operation to perform steering. It's summery.

By the way, since one end of the cylinder member 6 constituting the hydraulic cylinder 5 is connected to the pinion housing 4 by screwing, it is necessary to rotate the cylinder member 6 from the outside during assembly.

Therefore, when the cylinder member 6 is made of pipe material, a tool such as a spanner cannot fit into it, and sufficient tightening cannot be achieved.

Conventionally, therefore, a pipe with a thick wall or a part thereof is used as the cylinder member 6, and the diametrically symmetrical outer surface of the thick part of the pipe is ground to create a flat surface, into which a tool such as a spanner is fitted. Together, the cylinder member 6 can be rotated with a large force.

However, with this method, there is a problem that the cylinder member 6 has an unnecessary wall thickness, which increases its weight and makes it expensive.

[Purpose of invention]

In view of this, the present invention is a lightweight and inexpensive power steering device that uses a pipe material that has the minimum wall thickness necessary for a hydraulic cylinder for the pipe that constitutes the cylinder member, and that can be securely fastened using a tool. This was done with the purpose of providing a cylinder structure.

[Summary of the idea]

In order to achieve the above object, the present invention provides a hydraulic cylinder used in the hydraulic system of a power steering device of an automobile, in which the cylinder member is made of a pipe material with a wall thickness necessary for the hydraulic cylinder, and the cylinder member is made of a pipe material with a wall thickness necessary for the hydraulic cylinder, and the cylinder member is made of a pipe material with a wall thickness necessary for the hydraulic cylinder. A rotary operation annular member having a shape that can be rotated with a tool such as a spanner is fitted onto the outside, and the pipe material and the rotation operation annular member are press-fixed together by caulking through unevenness. be.

[Embodiment of the invention] The present invention will be described below with reference to the embodiments shown in FIGS. 1 to 3, and the same reference numerals are given to the same members as in FIG. 4.

The cylinder member 6 is made of a pipe material 7 having a wall thickness necessary for the hydraulic cylinder 5, and screws 8 and 9 for rear connection are formed at the ends thereof.

In the present invention, an annular member 10 for rotational operation is provided near one end of the cylinder member 6. This annular member 10 for rotational operation has an annular shape as shown in FIG. 2, and the outer peripheral surface at diametrically symmetrical positions is cut into a flat shape, and a flat surface portion that can be engaged with a tool such as a spanner. 11, 11, and is unrotatably fixed to the outer periphery of the pipe material 7 constituting the cylinder member 6 by caulking.

This caulking means has an unevenness 12 formed on the outer circumferential surface of the pipe material on which the annular member 10 for rotational operation is fitted, and the annular member 10 for rotational operation is fitted on the outer circumferential surface processed with the unevenness to attach the pipe material 7. By expanding by means such as press-fitting a core metal, the unevenness 12 is press-fitted into the inner circumferential surface of the annular member 10 for rotational operation and integrated. Note that the annular member 1 for rotational operation is smaller than the pipe material 7.
If the material of No. 0 is harder, unevenness 12 is formed on the inner peripheral surface of the annular member 10.

The unevenness 12 may be formed in any suitable form such as knurling or thread groove processing, but it is desirable to select a form that can be reliably connected in a fixed state in the direction of rotation.

Therefore, in the hydraulic cylinder structure of the power steering device according to the present invention, the annular member 10 for rotational operation is fitted onto the circumferential surface of a pipe material having a sufficient wall thickness as necessary for the cylinder, and the annular member 10 is fitted through the unevenness 12. Since it has an integrated structure, when the cylinder member 6 is screwed into the pinion housing, the flat surface portion 11 of the annular member 10 for rotation operation,
By applying a tool such as a spanner to 11 and turning it, a secure screw connection can be made, and since a pipe material having the required wall thickness can be used for the cylinder, the weight of the hydraulic cylinder does not increase. It also has excellent effects and can be obtained at low cost.

[Brief explanation of drawings]

Fig. 1 is a side view showing an embodiment of the hydraulic cylinder structure according to the present invention, with a half section cut away, Fig. 2 is a sectional view taken along the line shown in Fig. 1, and Fig. 3 is a partially enlarged sectional view of the main part. , FIG. 4 is a split perspective view showing an example of a hydraulic cylinder section of a power steering device. 6...Cylinder member, 7...Pipe material, 10...
... Annular member for rotational operation, 11 ... Flat surface part, 12
...Unevenness.

Claims (1)

[Scope of utility model registration request] In a hydraulic cylinder used in the hydraulic system of an automobile power steering device, the cylinder member of the hydraulic cylinder is made of pipe material with the thickness required for a hydraulic cylinder, and the pipe material can be rotated with a tool such as a spanner at the appropriate location. A hydraulic cylinder structure for a power steering device, characterized in that an annular member for rotational operation having a shape is fitted onto the outside, and a pipe material and the annular member for rotational operation are press-fixed together by caulking through unevenness.