JPS61132286A - Brush holding material for micromotor - Google Patents

Abstract

PURPOSE:To obtain the brush holding material for micromotor being firmly joined with shortening the production process by joining the connected part of different kind of metallic thin plate of the specified plate thickness with a laser welding. CONSTITUTION:The different kind of metallic thin plate of 0.05-0.8mm thickness formed by copper or copper alloy is connected in parallel or placed in parallel by overlapping both sides edge parts with inserting these into the jig for overlapping and the connected part of both metallic thin plates is welded by laser beam. The joined composite thin plate is then subjected to the heat treatment at the prescribed temp., if necessary, and cut in the prescribed shape.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a brush holding material for a micromotor, in which dissimilar gold IFJI plates are firmly bonded and the manufacturing process is shortened.

[Technical background of the invention and its problems] Some composite members include dissimilar metal plates joined together at their edges, but especially when the metal plates are thin plates, depending on the nature of the metals to be joined, In some cases, it is difficult to firmly join the edges.

For example, in the case of a brush holder for a micromotor, the tip part is made of Be-Qua gold alloy, which has a high degree of springiness and fatigue resistance, and the support part is made of brass, which has good electrical conductivity and is easy to solder. , copper, etc. are used. Both the tip and the support part are made of copper-based metals, and these copper-based metals generally have high thermal conductivity (approximately 8 times that of 14, and approximately twice that of aluminum), and are welded together. Oxides tend to form in welded areas, and these oxides can cause secondary bubbles and embrittlement, and when brass is welded, Zn evaporates and escapes, resulting in a considerable reduction in Zn in the welded areas. It has been extremely difficult to weld using conventional methods because of the problems such as impairing the uniformity of the composition and generating bubbles.

Conventionally, a brush holding material for a micromotor has been manufactured by joining the tip portion and the support portion by caulking, but this method has the disadvantage of complicating the manufacturing process and increasing costs.

[Object of the Invention] The present invention was made to solve such problems, and it is possible to firmly join dissimilar metal thin plates made of copper-based metal scraps,
Another object of the present invention is to provide a brush holding material for a micromotor that has a shortened manufacturing process.

[Summary of the Invention 1 That is, the micromotor brush holding material of the present invention has the following features:
Plate thickness 0.05-0.8mm made of copper or copper alloy
The side edges of the dissimilar metal thin plates to be welded are brought into contact with each other or are pressed together, and the contact portions of the dissimilar metal thin plates are joined by Lena welding.

Examples of the combination of thin metal sheets in the present invention include copper,
yellow m (CtJ-Zn), nickel silver (Ni-Qu-
zn> and phosphor bronze (3n-Cu-P);
Examples include combinations with thin plates made of Cu alloys, and examples of Be--Cu alloys include Berylco alloy (trade name, owned by The Beryllium Company, USA).

The present invention is characterized in that it is also possible to provide a brush holding material for a micromotor, which is made by firmly joining thin metal plates each having a different thickness and an extremely small thickness, and therefore, For example, the support part that requires strength is a normal size plate, while the tip part that requires a high degree of springiness is a micromotor that is formed by integrating individual thin metal plates with extremely small thickness. It is possible to provide a brush holding material for

The thickness of these metal thin plates is 0.05 to 0.8 mm, preferably 0.1 to 0.5 mm. Moreover, any combination of the thicknesses of the metal thin plates may be used as long as the thicknesses are within the above-mentioned range.

Next, a method for manufacturing the micromotor brush holding material of the present invention will be described.

Two types of thin metal plates are placed side by side or inserted into a jig for overlapping and placed side by side with both side edges overlapping, and the contact portions of both thin metal plates are laser welded.

Laser welding is carried out continuously or in pulses, for example at a feed rate of 2 m/min for an output of 1 kW, while protecting the welding point with an inert gas such as nitrogen gas or argon gas.

In addition, when welding the side edges of both thin metal plates by overlapping them, the direction of incidence of the laser beam needs to be in a specific direction depending on the combination of gold FA'a plates used. In the case of metal plates made of an alloy and phosphor-17 copper, it is preferable that the light be incident from the side of the metal plate made of phosphor bronze. 17-Welding methods other than the welding cannot achieve the desired strong joint.

Next, the bonded composite thin plate is heat-treated at around 315° C. if necessary, and cut into a predetermined shape to obtain 1 q of the intended micromotor brush holding material.

[Embodiments of the invention] Next, examples of the present invention will be described.

Example A thin metal plate made of Berylco alloy with a plate thickness of 0.07 mm and a gold plate made of phosphor bronze with a plate thickness of 0.2 mm.
The Iil plates were inserted into an overlapping jig, and a laser beam was applied from the phosphor bronze side of the bales, which were juxtaposed with their side edges partially overlapped, and laser welding was performed under the following conditions.

Shielding gas Argon output 1 kW Traveling speed a2 m/min Focus shift 111 m FL7.5 After heat-treating the obtained composite thin plate at 315±10°C for 2 to 3 hours, the thin plate is shaped horizontally from the vertical axis point to a predetermined shape. A brush holding material for a micromotor was obtained by cutting into pieces. The tensile shear strength of this micromotor brush holding material was 401 cg/-, and the fracture occurred in the phosphor bronze part and not in the joint part.

[Advantageous Effects of the Invention 1] As explained above, the micromotor brush holding material of the present invention improves workability because dissimilar metals can be easily joined by laser welding two metal thin plates juxtaposed. It has the advantage of being crushed and can be manufactured at low cost.

Furthermore, since the obtained composite thin plate has a strong dissimilar metal bending bond, it is most suitable as a reliable brush holding material for the microphone L1 motor.

Claims (2)

[Claims] (1) A plate made of copper or copper alloy with a thickness of 0.05 to 0.
A brush holding material for a micromotor, characterized in that side edges of 8 mm thin metal plates of different types to be welded are brought into contact with each other or overlapped, and the contact parts of the different metal thin plates are joined by laser welding. (2) The brush holding material for a micromotor according to claim 1, wherein the different metal thin plates have different thicknesses.