JP3520300B2 - Method of manufacturing brush piece for sliding - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a sliding brush used for a trimmer, a potentiometer and the like. 2. Description of the Related Art A so-called multi-wire type brush piece used for a trimmer, a potentiometer, etc., as shown in FIG. 5, has a large number of sliding pieces for improving the reliability and stability of electrical contact. It is composed of a moving element. In this method of manufacturing a brush piece, a so-called bus bar in which a large number of sliding wires pre-aligned and condensed is welded at a constant interval, cut, and the tip contact portion is formed into a semicircular shape by bending. . According to the prior art, since the strand is a thin wire having a diameter of about 0.08 mm, the degree of linearity of each line aligned and focused and the bending of the contact portion at the tip end. However, there is a problem that a part of the element wire is easily broken or the tip end is irregular, which tends to be irregular. SUMMARY OF THE INVENTION Accordingly, the present invention provides a method for welding a wire made of a noble metal or a noble metal alloy a plurality of times around a continuous body formed by winding a wire into a coil a plurality of times. It is characterized in that it is cut into brush pieces at individual locations. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory view showing a state in which a thin wire is wound in a circular shape, and FIG. 2 is a perspective view of a brush piece. A continuum 1 is formed by winding a thin wire of 30 WT% Ag-40WT% Pd-30WT% Cu having a wire diameter of 0.08 mm multiple times (six times in this embodiment) in a coil shape of 3 mm in diameter. After the surrounding opposing portions 2 were welded, a symmetrical portion deviated from the welding portion was cut as a cutting portion 3 to obtain two brush pieces 4. The cutting point may be any point within a range of 90 ° from the welding point, and the welding points need not be exactly symmetrical positions facing each other. A quality inspection was performed on 500 brush pieces thus obtained, and Table 1 shows the results. At the same time, as a comparative example, six thin wires each having a diameter of 0.08 mm made of 30 WT% Ag-40 WT% Pd -30 WT% Cu similar to those in the above-mentioned embodiment were aligned and focused by the conventional technique, and the thickness was 0.2 mm.
The base of a bus bar made of 80 WT% Cu-20 WT% Ni having a width of 0.5 mm and a length of 1 mm was welded, cut, and the contact portion at the tip was bent into the same shape as in the above example. [Table 1] As is clear from Table 1, the brush pieces of the examples have no irregularities in the tips and no thin wires are dropped off, and have a stable quality.
On the other hand, the brush piece of the conventional example has an irregular tip and a thin wire coming off, and has a quality having an unstable element. The shape of the coil is not necessarily limited to a circular shape. For example, a continuous body 1 wound on a symmetrically deformed coil as shown in FIG. 3 may be formed. By setting the symmetrical portion deviated from the welding portion 2 as the cutting portion 3, two brush pieces 4 were obtained, and the same inspection result as described above was obtained. According to the present invention described in detail above,
After welding two places around a continuous body formed by winding a wire made of a noble metal or a noble metal alloy into a coil shape multiple times, and cutting it at two surrounding places facing each other to make brush pieces, this brush piece This has the effect of providing good quality with no variation in the contact portion and no detachment of the thin wire. Further, since the dimensional accuracy is high and the number of manufacturing steps is small, there is an effect that a highly reliable brush piece can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory view showing a state in which a thin wire is wound, showing a first embodiment. FIG. 2 is a perspective view of a brush piece. FIG. 3 is an explanatory view showing a state in which a thin wire is wound, showing a second embodiment. FIG. 4 is a perspective view of a brush piece. FIG. 5 is a perspective view of a brush piece showing a conventional example. [Description of symbols] 1 Continuous body 2 Welding point 3 Cutting point 4 Brush piece

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) H01C 10/00 H01C 1/12 H01R 39/24 H01R 43/12

Claims (1)

(57) [Claims] [Claim 1] After welding two locations around a continuous body formed by winding a wire made of a noble metal or a noble metal alloy into a coil shape a plurality of times, cutting at two locations facing each other around the continuous body A method for manufacturing a sliding brush piece, wherein