【発明の詳細な説明】[Detailed description of the invention]
本発明は、直流小型モータの整流子用すり接点
材料（以下「すり接点材料」という。）の改良に
関する。
従来より直流小型モータの整流子外周の接点片
を作るすり接点材料としては主としてCuが用い
られてきたが、Cuは軟化温度が低く、直流を整
流させる為の整流子の回転すり接触中凝着現象が
生じ易くその為消耗が多く、また、接触抵坑が高
く且つ不安定でノイズが発生し、もつて直流小型
モータの回転数がばらつくという欠点があつた。
本発明はかかる欠点を解消すべくなされたもの
で、軟化温度を高くして凝着による消耗を防止
し、接触抵抗を低く安定させたすり接点材料を提
供せんとするものである。
本発明のすり接点材料は、Mn0.5〜５重量％及
び残部CuのCu合金から成るものである。
かかる本発明のすり接点材料に於いて、Mn0.5
〜５重量％及び残部CuのCu合金とするのは、Cu
の軟化温度を高くして直流小型モータの整流子の
回転中外周の接点片が凝着により消耗するのを防
止し、接触抵抗を低く且つばらつきの小さい安定
したものにする為で、0.5重量％未満ではCuの軟
化温度の上昇効果が小さく、接点片の凝着による
消耗を防止できなく、５重量％を超えると酸化物
の生成量が多くなつて、接点片の接触抵抗が高く
且つばらつきが大きくなつて不安定となるもので
ある。
次に本発明によるすり接点材料と従来のすり接
点材料にて作つた直流小型モータの整流子外周の
接点片について説明する。
後記の表の左欄に示す成分組成の本発明の実施
例であるすり接点材料と従来例のすり接点材料に
て厚さ0.2mmの接点片を作り、この接点片を図面
に示す如く外周に３枚備えた直径10mm、長さ６mm
の整流子１の外周面の上下に、Ag−Cu合金より
成る巾1.0mm、厚さ0.2mm、長さ10mmの刷子板材２
を１枚有する刷子接点３を相対向するようにすり
接触させて、後記の試験条件にて整流子１の回転
試験を行い、接点片１ａの消耗量と接触抵抗を測
定した処、後記の表の右欄に示すような結果を得
た。
試験条件
電 圧：12V
電 流：直流100ｍＡ
整流子の回転数：2800回転／分
整流子の回転時間：500時間
刷子接点の接触力：10ｇ
The present invention relates to improvements in a sliding contact material (hereinafter referred to as "sliding contact material") for a commutator of a small DC motor. Traditionally, Cu has been mainly used as a sliding contact material to make contact pieces around the commutator of small DC motors, but Cu has a low softening temperature and tends to stick during sliding contact when the commutator rotates to rectify DC current. These problems tend to occur, resulting in a large amount of wear and tear, and the contact resistance is high and unstable, resulting in noise, and the number of revolutions of the small DC motor fluctuates. The present invention has been made to solve these drawbacks, and aims to provide a sliding contact material that has a high softening temperature, prevents wear due to adhesion, and has a low and stable contact resistance. The sliding contact material of the present invention is made of a Cu alloy containing 0.5 to 5% by weight of Mn and the balance being Cu. In such a sliding contact material of the present invention, Mn0.5
The Cu alloy with ~5% by weight and the balance Cu is Cu
0.5% by weight to increase the softening temperature of the DC motor to prevent the contact pieces on the outer periphery from being worn out due to adhesion during rotation of the commutator of a small DC motor, and to make the contact resistance low and stable with little variation. If it is less than 5% by weight, the effect of increasing the softening temperature of Cu is small and it is not possible to prevent wear of the contact piece due to adhesion. It grows and becomes unstable. Next, a contact piece for the outer periphery of a commutator of a small DC motor made of a sliding contact material according to the present invention and a conventional sliding contact material will be explained. A contact piece with a thickness of 0.2 mm was made using the sliding contact material according to the embodiment of the present invention and the conventional sliding contact material having the composition shown in the left column of the table below, and this contact piece was molded around the outer periphery as shown in the drawing. Diameter 10mm, length 6mm with 3 pieces
A brush plate material 2 made of Ag-Cu alloy with a width of 1.0 mm, a thickness of 0.2 mm, and a length of 10 mm is placed above and below the outer peripheral surface of the commutator 1.
A rotation test was carried out on the commutator 1 under the test conditions described below by bringing the brush contacts 3 having one brush contact piece 3 facing each other into sliding contact, and the wear amount and contact resistance of the contact piece 1a were measured. The results shown in the right column were obtained. Test conditions Voltage: 12V Current: DC 100mA Commutator rotation speed: 2800 revolutions/min Commutator rotation time: 500 hours Brush contact force: 10g
【表】
前記の表で明らかなように従来例の整流子外周
の接点片消耗量は30〜40μｍであるのに対し、実
施例の整流子外周の接点片消耗量は10〜20μｍ
で、著しく少なく耐消耗性に優れていることが判
る。また従来例の接点片では接触抵抗が１〜２Ω
であるのに対し、実施例の接点片では接触抵抗が
0.1〜0.3Ωで著しく低く且つばらつきが小さく安
定していることが判る。
以上詳記した通り本発明のすり接点材料は、軟
化温度が高いので、これにより作つた直流小型モ
ータの整流子外周の接点片はすり接触中に凝着に
より消耗することがなく、接触抵抗が低く安定し
ノイズの発生がなく、また耐消耗性が優れ、もつ
て安定した回転の直流小型モータが得られるもの
である。[Table] As is clear from the above table, the wear amount of the contact pieces on the outer circumference of the commutator in the conventional example is 30 to 40 μm, whereas the amount of wear on the contact pieces on the outer circumference of the commutator in the example is 10 to 20 μm.
It can be seen that the wear resistance is extremely low. In addition, the contact resistance of conventional contact pieces is 1 to 2Ω.
On the other hand, in the contact piece of the example, the contact resistance is
It can be seen that it is extremely low at 0.1 to 0.3Ω and stable with little variation. As detailed above, since the sliding contact material of the present invention has a high softening temperature, the contact pieces on the outer circumference of the commutator of a small DC motor made using this material will not be worn out due to adhesion during sliding contact, and the contact resistance will be reduced. It is possible to obtain a small DC motor that has low and stable rotation, does not generate noise, has excellent wear resistance, and has stable rotation.
【図面の簡単な説明】[Brief explanation of drawings]
図は直流小型モータの整流子とすり接点との接
触状態を示す斜視図である。
１……整流子、１ａ……接点片、２……刷子板
材、３……刷子接点。
The figure is a perspective view showing a contact state between a commutator and a sliding contact of a small DC motor. 1...Commutator, 1a...Contact piece, 2...Brush plate material, 3...Brush contact.