Method and device for manufacturing flat commutator

Abstract

A method and a device for manufacturing a flat commutator, the method comprising the steps of fitting metal pieces forming a segment (3) to a cartridge (21), pressing the metal pieces by a punch (25) for performing a cartridge fitting step, wherein projections (22) radially formed and arranged between the metal pieces are formed on the cartridge (21) to restrict the circumferential movement of the metal pieces, an outer peripheral wall (24) in contact with the end part of the metal pieces is formed on the outer peripheral part of the cartridge (21) to restrict the radial movement of the metal pieces, double annular projections (27a) and (27b) are formed on the surface of the punch (25) opposed to the cartridge (21), and the annular projections (27a) and (27b) are pressed against the metal pieces to fit the side face of the metal pieces to the projections (22) of the cartridge (21).

Description

technical field [0001] The present invention relates to a method of manufacturing a commutator for a rotating electrical machine, and more particularly to a method of manufacturing a disc-type flat commutator. Background technique [0002] In recent years, among motors used in electric power steering, engine starters, fuel pumps, etc., motors using flat commutators (planar commutators) have appeared due to the demand for device miniaturization. This flat type commutator differs from a general cylindrical commutator in that it has a disk-shaped brush sliding surface extending radially from the rotational axis. The brush is in sliding contact with the sliding surface of the brush from the axial direction to switch the armature current. [0003] The sliding surface of the brush is composed of a plurality of radially arranged commutator segments made of a metal member called a commutator metal. Each commutator segment is molded integrally with the synthetic resin main body. E...

AI Technical Summary

Problems solved by technology

[0008] However, when the flat punch 59 is used, the pressurized area becomes larger, and the load required to bring the chuck 53 and the commutator segments 54 into close contact becomes larger than when the fixed pressing protrusion 51 is used (for example, 12t→25t).

Therefore, larger equipment is required than the fixed pressing method, and a problem of so-called increase in equipment cost arises.

In addition, there is also a problem that the commutator segments 54, the chuck 53, the flat punch 59, etc. are easily damaged due to the dimensional error of the commutator segments 54, etc., where the load is concentrated.

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