JPS6410915B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a metal tube of a brush holder, the end of which is sealed in the opposite direction of brush insertion as a terminal plate, and a method for fixing this terminal plate.

Since the brush holder is used by being attached to a predetermined location within a small power tool, for example, the terminal side of the metal tube is surrounded by an insulator, and an appropriate attachment means is provided around the outer periphery of the insulator.

Conventionally, the terminal plate of this type of metal tube was fixed with silver solder, but in this case, there is a risk that silver solder may enter the inside of the metal tube during welding, and if silver solder adheres to the inside, The problem was that the sliding of the brush was inconvenient, resulting in unstable quality, and silver solder welding was relatively expensive, resulting in high costs.

This invention aims to eliminate the above-mentioned drawbacks and will be explained below with reference to embodiments.

Reference numeral 1 denotes a brush holder formed of a metal tube 2 and an insulator 3, and the end of the metal tube 2 in the direction opposite to the insertion direction of the brush 4 is sealed with a terminal plate 5.

The above-mentioned sealing is necessary to prevent resin from flowing in when surrounding the terminal side of the metal tube 2 with the insulator 3.

The terminal plate is thinner than the wall thickness of the metal tube and has a shape that can be inserted flatly into the metal tube, and is placed in a guide recess into which the terminal plate of the base 6 is fitted,
Next, the metal tube is held and fixed by appropriate means at a position where the terminal plate can be inserted into the metal tube.

Under this condition, in order to apply pressure only to the peripheral edge of the terminal plate, a recess 8 is provided at the tip, and when the movable rod 7 moves up and down inside the metal tube, it does not touch the inner wall of the tube, and the movable rod 7 is moved downward from above the metal tube. Apply pressure to the periphery of the terminal board.

Because the terminal plate is thinner than the metal tube by the above-mentioned hammering pressure, the peripheral edge of the terminal plate is extended and tightly fixed to the inner wall of the metal tube without deforming the metal tube.

In this case, since a recess 8 is provided at the tip of the movable rod 7 and pressure is applied only to the periphery of the terminal board, the periphery of the terminal board extends horizontally, and there is no impact pressure on the part facing the recess of the terminal board, causing warpage. The terminal board can be fixed horizontally by absorbing it and forming a lump-like shape.

In the figure, reference numeral 9 denotes a spring that electrically connects the brush 4 and the terminal plate 5 and keeps the brush under normal pressure.

According to the present invention, a recess 8 is provided at the tip of the movable rod 7, and only the peripheral edge of the terminal plate 5 is pressed and only this part is extended, so that the terminal plate can be properly and closely fixed without warping. In addition, since it is fixed by pressing the terminal plate, it has the effect of lowering the cost compared to conventional silver solder welding, which is relatively expensive, and is extremely profitable.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a front view of a metal tube. Figure 2 is a plan view of the metal tube before the terminal side is fixed with a terminal plate. FIG. 3 is a sectional view taken along line AA in FIG. Figure 4 is a plan view of the terminal board before it is fixed to a metal tube. FIG. 5 is a sectional view before the terminal plate is fixed to the metal tube with a movable rod. Figure 6 is a sectional view when the process is completed. FIG. 7 is a front view of the brush holder. FIG. 8 is a plan view of the same. FIG. 9 is a sectional view of the brush inserted into the brush holder. 2... Metal tube, 7... Movable rod, 5... Terminal board,
8... recess, 6... stand.

Claims (1)

[Claims] 1. In a brush holder that seals the end of a metal tube in the direction opposite to the brush insertion direction with a terminal plate, a terminal plate 5 thinner than the wall thickness of the metal tube 2 is placed at a predetermined location on the stand 6, and the terminal plate The metal tube 2 is held and fixed by appropriate means in a position where the metal tube 2 can be inserted into the terminal plate, and a movable rod 7 is provided with a recess 8 at its tip so as to press only the peripheral edge of the terminal plate and does not touch the inner wall of the metal tube 2. A method for fixing a terminal plate of a metal tube of a brush holder, in which the peripheral edge of the terminal plate is pressed from above the metal tube and the terminal plate is closely fixed by the extension of the peripheral edge.