JPS61232022A - Working method for forming recess to pipe - Google Patents

Abstract

PURPOSE:To press and form extremely efficiently a pipe by pressing the pipe to a prescribed shape by means of a supporting core and a movable core inserted into the pipe as well as a master die then drawing the movable core and supporting core in this order out of the pipe. CONSTITUTION:An inside die which can be exactly inserted into the pipe 1 to be worked is divided to the supporting core 2 for supporting the inside surface of the pipe 1 and the movable core 3. Such inside die (a) is inserted into the pipe 1 and the pipe is subjected to pressing in accordance with the conventional practice by using the master die (b) corresponding to such inside die (a) to form a recess 4 to a prescribed shape and thereafter the core 3 is slid in the longitudinal direction of the pipe 1 and is drawn to the outside from the pipe 1. The worked pipe 1 is detached from the core 2 and is removed by utilizing the cavity formed after drawing out of the core 3. Since the intended working is made possible by one time of pressing in the above-mentioned manner, the working efficiency is improved and the cost is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a processing method for forming locking recesses in automobile headrest pars, chair lifting columns, and the like.

[Conventional technology]

For example, a five-piece stopper made of pipe for an automobile has a locking recess for vertical adjustment.

Conventionally, with this processing method, the headrest was formed by cutting from the machined ζ2, but since the plate meat was removed, the strength was inferior.

For this reason, recently, as a method to solve this drawback, first make a dent by lightly pressing C2, which has poor workability.
This had the disadvantage of not being able to be mass-produced, which made the product expensive.

Furthermore, cutting by machining also had the disadvantage of reducing the strength of the headrest par.

[Problem that the invention seeks to solve]

The technical object of the present invention is to provide a processing method for forming a recess in a pipe, which solves such drawbacks and can easily and efficiently form a recess of a predetermined shape by press working.

[Means for solving problems]

The inner mold (a), which is inserted just right into the pipe (13) to be processed, is inserted into the support core (2) that supports the inner surface of the pipe (1).
) and the movable core (3) and ζ are divided into two, insert this inner mold (a) into the pipe (1), and insert the outer mold (1) corresponding to this inner mold (a).
After forming a recess (4) of a predetermined shape by pressing in the usual manner using t(bl), slide the movable core (3) in the length direction of the pipe (1) to remove the outside of the pipe (1). Then, using the empty space after the movable core (3) is pulled out, the processed pipe (1) is separated from the support core (2) and taken out.

〔Example〕

The division ratio between the supporting core (2) and the movable core (3) is preferably about 1:3, but it may be half and half.

A pipe (
1) The core bodies (7) and (8) are connected to each other via the locking steps (51 (6)) whose ends are locked, and the core body of the support core (2) is fixed and does not move during movement. The core body of the child (3) (83 is a cylinder, etc. C: It is better to provide it so that it can slide more freely.

Figure II (b) shows the case where several dents are pressed once, but the dents may be pressed one by one by moving the outside mold.

〔Effect of the invention〕

Pull out the movable core (3) to the outside, and
Since this is a processing method in which the processed pipe (1) is separated from the support core (2) and taken out using the empty space after the pipe is pulled out, it is possible to press the pipe (1) once, which was previously impossible. Since the inner surface of the pipe (1) is firmly supported by the inner mold (aJ), the recess (4) of a predetermined shape can be formed in a single press process without requiring machining.

Therefore, since only one press work is required, work efficiency is greatly improved compared to the conventional two-step process of press work and machining, mass production is possible, and product cost can be reduced accordingly.

This formed recess (4) is only pressed and not machined at all, so it does not reduce the strength of the pipe (1) itself, making it strong and durable for use as a headrest bar or chair lifting support. C: It has isotropic features.

[Brief explanation of drawings]

Figure 1 is a slope view of the pipe, Figure 112 is a slope view of a pipe with a recess machined, Figures 3 and 4 are a front cross-sectional view of the processed mold, Figure 5 is a side cross-sectional view, and Figure 6 is a slope view of the headrest. It is a diagram. (a)...white star, (bl...outer mold, (1)...pipe,
(2)...Support core, (3)...Movable core, (4)...
dent.

Claims (1)

[Claims] An inner mold that is inserted into the pipe to be machined is divided into a support core that supports the inner surface of the pipe and a movable core.
This inner mold is inserted into the pipe, and the inner mold and the corresponding outer mold are used to perform press processing in the usual manner to form a recess of a predetermined shape, and then the movable core is slid in the length direction of the pipe. A processing method for forming a recess in a pipe, which is characterized in that the pipe is pulled out from the pipe by the movable core, and the hollow space after the movable core is pulled out is used to separate the processed pipe from the support core and take it out.