JPH03134251A - End part chamfering method for plated mechanical part - Google Patents

Abstract

PURPOSE:To reduce unevenness of a film thickness with current density changed continuously and generation of turbulence eliminated in plating fluid by chamfering an end part between an internal part and a through hole with high density energy irradiated before a plating layer is formed in the internal part having the through hole. CONSTITUTION:An end part 4 in a cylinder 1 is chamfered by irradiating it with high density energy of laser or the like and formed into a shape having curvature R. Thereafter by performing a plating process, a plating layer 3 of shape, having the curvature R in the end part 4, is formed. Since a port internal surface is prevented from being much plated as compared with a case not chamfered, this layer 3 is also prevented from being followed by deteriora tion of suction-exhaust efficiency. Accordingly, unevenness of a plated film thickness can be reduced, while in the case of using the cylinder 1 in which Si is deposited by an Al-Si alloy in the base material, since an insulator of Si is changed into a fine state by partly melting a surface of the cylinder by laser irradiation with conductivity of an Al part deteriorated, current density in the vicinity of the end part 4 is uniformly obtained further with unevenness of the plating film thickness enabled to reduce.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application] The present invention relates to a method for chamfering the end of a plated machine part having a through hole inside, such as a cylinder.

[Prior Art] Conventionally, when applying a plating layer 3 to the inner surface of the cylinder 2 in a plated machine part, for example, a part having a through hole 2 inside the cylinder 1 as shown in FIG. 3, electrolytic plating is used. In this case, the current density becomes high near the end 4 between the cylinder 1 and the through hole 2, and in the case of electroless plating, the flow of the plating solution is disturbed near the end 4. Also in this case, as shown in FIG. 4, a large amount of plating layer 8 tends to be deposited, and a large number of man-hours are required to achieve accuracy on the inner surface of cylinder 1 in the subsequent honing process.

Therefore, at present, the end portion 4 is chamfered by inserting a router through the opening of the cylinder 1 before the plating process.

[Problems to be Solved by the Invention] However, in the method of chamfering the end portion 4 using the conventional router described above, since the chamfering is performed within a narrow cylinder, the shape is close to C-chamfering, and current density discontinuity or However, it is not possible to completely eliminate disturbances in the flow of the plating solution, and as described above, a large number of man-hours are required to achieve accuracy in the honing process.

The present invention solves this problem by providing continuous changes in current density and preventing disturbances in the flow of the plating solution.
It is an object of the present invention to provide a method for chamfering the edges of plated machine parts that can reduce variations in the thickness of the plated film.

[Means for Solving the Problems] To achieve this, the method for chamfering the end of a plated mechanical component of the present invention provides a method for chamfering an end of a plated mechanical component in which a through hole is formed inside the mechanical component and a plating layer is formed therein. The method is characterized in that high-density energy irradiation is applied to the end portion between the inside and the through hole to chamfer the end portion.

[Operations] In the present invention, mechanical parts are chamfered by high-density energy irradiation such as laser beams to give the edges a shape with curvature, and then plating is performed to form a plated layer with curvature at the edges. Therefore, variations in the plating film thickness can be reduced. [Example 1] Examples of the present invention will be described below with reference to the drawings. 1st
The figure is a sectional view of a main part for explaining the method for chamfering the end of a plating machine component according to the present invention.

FIG. 1 shows an embodiment applied when a plating layer 3 is applied to the inner surface of the cylinder 2 in a component having a through hole 2 inside the cylinder 1 or the like described in FIG.

In this embodiment, first, as shown in Figure (a), the end portion 4 of the cylinder 1 is irradiated with high density energy such as a laser.
(b) The end portion 4 is shaped to have a curvature R as shown in the figure. The laser may be irradiated directly onto the end portion 4, or may be irradiated by disposing a mirror inside the cylinder.

Thereafter, a plating process is performed to form a plating layer 3 having a shape having a curvature R at the end portion 4 as shown in (0) figure. This is the fifth case when chamfering is not performed.
As shown in the figure, since a large amount of plating does not adhere to the inner surface of the port, there is no reduction in the intake/exhaust efficiency.

Therefore, variations in plating film thickness can be reduced.

In addition, the base material of the cylinder 1 is made of Al-8t alloy and Si.
When using a material in which Si is precipitated due to a high content, laser irradiation partially melts the cylinder surface and makes the insulator Si finer.
Since the electrical conductivity in the R portion decreases, when performing electrolytic plating, the current density becomes uniform near the end 4 between the cylinder 1 and the through hole 2, and variations in the plating film thickness can be further reduced.

FIG. 2 shows another example to which the present invention is applied, in which the piston 5
In the case where the inner surface of the through hole 6 into which the piston pin is inserted is plated, the end portion 7 may be plated.

[Effects of the Invention] As explained above, according to the present invention, it is possible to reduce the variation in the plating film thickness at the edge where the current density changes continuously and does not cause disturbance in the flow of the plating solution. Since the shape can be obtained, it is possible to easily obtain precision when polishing sliding parts of plated machine parts.

In addition, high-density energy irradiation using a laser or the like makes the current density uniform, and in the case of electrolytic plating, it is possible to further reduce variations in plating film thickness. Additionally, laser processing is easier to automate than laser processing.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a main part for explaining the method of chamfering the end of a plating machine member according to the present invention, Fig. 2 is a partial cross-sectional view of a piston to which the present invention is applied, and Fig. 3 is a cross-sectional view of a piston to which the present invention is applied. FIGS. 4 and 5 are cross-sectional views of main parts for explaining the conventional problems. DESCRIPTION OF SYMBOLS 1... Cylinder, 2.6... Through hole, 3... Plating layer, 4.7... End part, 5... Piston.

Claims (1)

[Claims] (1) In a mechanical component having a through hole inside and forming a plating layer inside the part, before forming the plating layer, high-density energy irradiation is applied to the end between the inside and the through hole,
A method for chamfering an end of a plated machine part, the method comprising chamfering the end.