JPH0735005B2 - Hollow shaft member processing method - Google Patents

Description

TECHNICAL FIELD The present invention relates to an improvement in a method of processing a hollow shaft member having a finish processing portion on its outer shape.

[Prior Art] While drilling the shaft center of a solid material (hereinafter referred to as "workpiece"), at least a part of the outer shape is distorted in the previous process and the surface black skin is removed, When manufacturing a hollow shaft member by performing a finishing process for finishing to a finished dimension and surface roughness, for example, when processing a steering knuckle mainly used as a vehicle part such as an automobile, conventionally, the following processes are performed. Do in order.

First step: A center hole for holding the solid work is machined in both ends of the solid work.

Second step: The work is held by the center holes and the outer shape is cut.

Third step: The outer shape of the machined work is held, and the axial center part is perforated.

Fourth step: induction hardening is performed on the surface of a predetermined portion of the outer shape of the work.

Fifth step: center machining is performed on both ends of the work hole.

Sixth step: The work is held at both of the above centers to finish the outer shape.

[Problems to be Solved by the Invention] As described above, according to the conventional processing method, since the drilling is performed in the third step, the center hole processed in the first step is removed in the third step. Therefore, in order to finish the outer shape in the sixth step, it is necessary to perform the center hole processing again in the fifth step. That is, it was necessary to perform the center hole machining twice (first step and fifth step).

The center hole that is provided to hold the workpiece at the time of machining the outer shape in the post process is essentially unnecessary for the function of the final product, and it is not necessary to spend two steps for machining the center hole. It is uneconomical in terms of manufacturing cost.

[Object of the Invention] The present invention has been made in view of the above problems, and in the processing of a hollow shaft member, by devising the order of the processing steps, the center hole processing step is reduced and the manufacturing cost is reduced. The purpose is to

[Means for Solving Problems] Therefore, according to the present invention, center holes for holding a work are machined on both end surfaces of a solid work, and the work is held by the center holes to form a work outline. After cutting, the work is held in both of the center holes to finish the work outline, and then the finished work is held to perform axial drilling on the work. Is.

[Effect of the Invention] According to the present invention, since the drilling is performed after the finishing of the outer shape of the work is completed, it is not necessary to perform the center drilling twice. Therefore, as compared with the conventional processing method, the center hole processing step can be reduced once and the manufacturing cost can be reduced.

[Embodiment] An embodiment of the present invention will be described below with reference to the accompanying drawings when applied to the processing of a steering knuckle of a vehicle.

As shown in Fig. 1, steering knuckle machining is
The steps are performed in the following order.

In the drawing, the processed portion in each step is shown by a thick line.

First, in step I, as shown in FIG.
Both end faces of the shaft center part are cut, and center holes 2 and 3 having a predetermined diameter and a predetermined depth are formed from the respective cut end faces 6 and 7. This center hole machining is work 1
The outer peripheral surface of the shaft is held.

Next, in step II, as shown in FIG.
In 3 and 3, the work 1 is held and the outer shape A is cut.

Then, in step III, as shown in FIG. 1c, induction hardening is performed on the partial surface 4 of the outer peripheral surface of the shaft portion and the partial surface 5 of the stepped portion of the work 1. Only the above-mentioned partial surfaces 4 and 5 are quench-hardened by this induction hardening, and the axial center of the work 1 maintains the softness of the base material.

Next, in step IV, as shown in FIG. 1d, the distortion of the outer shapes B and C and the surface black skin caused by the induction hardening in the above step III are removed, and the outer shapes B and C are given a predetermined finishing dimension and surface roughness. Grinding is done to finish the product. This grinding process is Step I
The work 1 is held by the center holes 2 and 3 machined in.

Finally, in step V, as shown in FIG. 1e, the outer peripheral surface of the shaft portion of the work 1 finished in step IV is held, and a hole 8 in the longitudinal axis direction is formed in the shaft center portion of the work 1. Drill holes to provide them.

As described above, according to the present invention, since the boring process (process V) is performed after the outer shape finishing process of the work I in the process IV, it is not necessary to process the center hole twice. . Therefore, as compared with the conventional machining process, the center hole machining process can be reduced once and the manufacturing cost can be reduced.

[Brief description of drawings]

Fig. 1a is a vertical cross-sectional view of the workpiece in the center hole machining process, Fig. 1b
Figure is a vertical section of the workpiece in the external machining process, Fig. 1c is a vertical sectional view of the workpiece in the induction hardening process, Fig. 1d is a vertical sectional view of the workpiece in the external finishing process, and Fig. 1e is a drilling process. It is a longitudinal cross-sectional view of the work in the process. 1 ... Workpiece, 2 ... Center hole, 3 ... Center hole, 6,7
…… Work end face, 8 …… hole, A …… outer shape, B, C …… outer shape.

Claims (1)

[Claims] 1. A step of machining a center hole for holding a work on both end surfaces of a solid work, respectively, and a step of holding a work by the both center holes and cutting an outer shape of the work.
Having a step of holding the work in both center holes and finishing the outer shape of the work, and a step of holding the outer shape of the finished work and making a hole in the work in the axial direction. And a method for processing a hollow shaft member.