JPH0127565Y2 - - Google Patents

Description

[Detailed description of the invention] "Field of industrial application" The present invention relates to a grounding structure for an enamel substrate, and particularly to a grounding structure suitable for the case where the work of grounding the enamel board and the work of attaching mechanical members are performed simultaneously. It is something.

``Prior Art'' As shown in the example in Figure 1, a so-called enamel substrate has a structure in which the surface of a metal core (usually a steel plate for enamel) 1 is covered with an enamel layer 2. It is used as a printed circuit board with excellent heat resistance and chemical resistance by mounting electric circuit conductors 3 etc. printed and fired using film circuit technology or the like. In this case, it is effective to ground the metal core 1 in terms of stability of the electric circuit, low noise characteristics, etc. That is, in the example shown in FIG. 1, the enamel layer 2 is removed by a method such as sandblasting, a part of the metal core 1 is exposed, and the exposed surface 4 is plated with nickel, and then, This is a grounding structure in which a grounding lead wire 5 is connected with solder 6 or the like.

However, with this structure, masking work is required to prevent damage to the electric circuit conductor 3 during sandblasting, and when attaching the enamel board to mechanical parts, etc., it is necessary to use a grounding lead. There were problems such as the work involved in connecting the wire 5 to the mechanical parts, which increased the number of steps and increased costs.

``Purpose of the invention'' The present invention was developed in view of the above circumstances, and it improves work efficiency by simultaneously carrying out the work of attaching the enamel board and the grounding work, and also prevents phenomena such as clutches occurring in the enamel enamel layer. The purpose is to effectively prevent this.

"Structure of the invention" In order to achieve these objects, the present invention provides a core exposed portion continuous to the through hole on at least one side of a metal core having a through hole, and a metal component is tightly attached to the opposite side of the exposed core portion. In addition, an electrical connection portion is provided that presses the exposed core portion integrally with the metal component.

“Embodiment” An embodiment of the present invention will be described below based on the drawings. As shown in FIG. 2, in the enamel substrate according to one embodiment, a through hole 11 is provided in the metal core 1, and an enamel enamel layer is formed inside the through hole 11 and on one side of the metal core 1. 2, the core exposed portion 12 is provided, and the other surface of the enamel enamel layer 2 where the core exposed portion 12 is not provided (the lower surface in the example in FIG. 2) is in close contact. A metal mechanism member 13 is provided, and a part of this metal mechanism member 13 is in pressure contact with the core exposed portion 12.

That is, the through hole 11 is formed in advance by the metal core 1.
However, during normal enameling, the enamel adheres to the inside of the through hole 11 and is fired, so the inside of the through hole 11 is heated at the same time as the core exposed portion 12 is formed. Removal of the enamel is done. In other words, the core exposed portion 12 is formed by removing the fired enamel enamel layer 2 on at least one side of the enamel substrate and around the through hole 11 using a diamond grinding wheel or the like to form the core exposed portion 12, and The enamel in the through hole 11 is also removed to expose the metal core 1, and these are exposed as the core exposed portion 12.
The state is continuous. By performing such processing, the mechanical precision of the inner surface of the through hole 11, etc. can be improved.

On the other hand, the metal component 13 has a flange portion 14
A support portion 15 such as a flange surface that closely contacts and supports the other surface of the enamel substrate on which the exposed core portion 12 is not provided (the lower surface in the example of FIG. 2).
is provided, and a cylindrical portion 16 that protrudes from the support portion 15 and is inserted into the through hole 11 is provided,
The outer diameter of the cylindrical portion 16 is set to such an extent that it can be precisely fitted into the through hole 11, and its length is set to be slightly larger than the depth of the through hole 11. Furthermore, by caulking the outer periphery of the cylindrical portion 16 or the like, an electrical connection portion 17 is provided in the exposed core portion 12 in a close state, and the enamel substrate is sandwiched between the support portion 15 and the electrical connection portion 17. Note that a bearing hole 18 is provided at the center of the cylindrical portion 16 when the metal component 13 is a bearing for a motor.

In addition, the core exposed portion 12 and the metal component 13
A conductive or rust-preventing treated film 19 is provided on and across these. When such a treated film 19 is used for both conductivity and rust prevention, for example, it is a high temperature firing type conductive paste, room temperature drying type conductive paste, nickel plating, etc., and when the main purpose is rust prevention, it is Rust paint, anti-rust oil, etc. are used.

Further, when the metal component 13 is a grounding component, the metal core 1 is grounded as shown by the chain line at the same time as the exposed core portion 12 and the electrical connection portion 17 come into contact.

Note that if there is a step of providing the electric circuit conductor 3 after forming the core exposed portion 12, a conductive paste may be printed and fired on the core exposed portion 12.

"Effects of the Invention" As explained above, according to the present invention, the following effects can be achieved.

(a) Since the electrical connections of the metal components are placed in pressure contact with the metal core, electrical connections can be made at the same time as the installation of the components, improving work efficiency and Can be applied to a range of fields.

(b) It has a structure in which the exposed core portion is pressed into contact with the core through electrical connection, and is separated from the enamel layer, thereby preventing the occurrence of cracks in the enamel layer.

(c) Assembly accuracy can be improved because the through-hole and core exposed portion are used for assembly.

[Brief explanation of drawings]

FIG. 1 is a partially omitted front sectional view showing a conventional example of a grounding structure for an enamel substrate, and FIG. 2 is a partially omitted front sectional view showing an embodiment of the present invention. 1... Metal core, 2... Enamel substrate, 3...
Electric circuit conductor, 11... Through hole, 12... Core exposed part, 13... Metal component, 15... Support part,
17...Electrical connection portion, 19...Treatment film.

Claims (1)

[Claims for Utility Model Registration] (1) In an enamel substrate formed by covering the surface of a metal core 1 with an enamel layer 2, a core exposed portion 12 continuous to a through hole 11 is provided on at least one side of the metal core, and the core An enamel substrate characterized in that a metal component 13 is disposed in close contact with the opposite surface of the exposed portion, and an electrical connection portion 17 is provided integrally with the metal component to support the exposed core portion in pressure contact. grounding structure. (2) The grounding structure for an enamel substrate according to claim 1, which is characterized in that a conductive or rust-preventing treated coating 19 is provided on the exposed core portion 12 and the electrical connection portion 13.