【発明の詳細な説明】[Detailed description of the invention]
本発明は、刷子用摺動接点材料の改良に関す
る。
従来、摺動接点材料としては各種材料が用いら
れ、とりわけ刷子接点用の材料としては、Pd30
〜70重量％、Ag30〜70重量％より成る合金材料
が広く用いられていた。
然し乍ら、この合金材料で製作した刷子接点で
は、整流子との摺動時の耐摩耗性が劣り、摩耗粉
が生じ易くノイズ発生の原因となつていた。
本発明は、斯かる欠点を解消すべくなされたも
のであり、前記合金材料を基材としてこれに特定
の材料を僅かに添加させて、耐摩耗性を向上させ
た刷子用摺動接点材料を提供せんとするものであ
る。
本発明の刷子用摺動接点材料は、組成比で
Pd30〜70重量％、Ag30〜70重量％のPd−Agが
92.0〜98.9重量％及び残部がMn1〜５重量％、
Si、Bi及びGeの少なくとも一種を合計で0.1〜3.0
重量％から成るものである。
本発明の刷子用摺動接点材料に於いて、組成比
でPd30〜70重量％、Ag30〜70重量％のPd−Ag
が92.0〜98.9重量％及び残部がMn1〜５重量％、
Si、Bi及びGeの少なくとも一種を合計で0.1〜3.0
重量％としている理由は、前記合金材料の耐摩耗
を向上すべく、Mnにより鋳造時の湯流れを改善
し、またSi、Bi及びGeの少なくとも一種により
結晶粒の微細化をはかる為である。ここで、Si、
Bi及びGeはお互いその効果を減殺し合うもので
はなく、従つて単独でも、或いは２種以上とする
こともできる。更に、MnとSi、Bi及びGeのうち
少なくとも一種との複合添加による相乗効果と相
俟つて硬くする為で、Mnが１重量％あるいはSi、
Bi及びGeの少なくとも一種が合計で、0.1重量％
未満ではその効果を発揮できず、Mnが５重量％
あるいはSi、Bi及びGeの少なくとも一種が合計
で３重量％を越えると酸化物の発生量が多くな
り、接触抵抗が高くなり、その上不安定となるも
のである。
また、Pd、Agの含有量は前記従来の合金材料
の組成比に変更を加えない範囲とすることによ
り、従来の合金材料の特性は損なわれることなく
発揮されるものである。
次に従来の合金材料を基材とし、これにMnと
Siを添加し、表の実施例１に示す成分組成の刷子
用摺動接点材料とし、以下同様にして表に示す成
分組成の本発明による刷子用摺動接点材料と従来
の刷子用摺動接点材料を用いて夫々線径0.7mmの
刷子線材を作り、これを各々長さ８mmに切断し、
２本並列させて一端を幅10mm、長さ13mm、厚さ
0.2mmの台材に溶接し、他端に2Rの円弧状の接触
部を曲成して刷子接点を作つた。そして夫々の刷
子接点を円盤状の整流子に接触させ、整流子を正
逆回転させて下記の試験条件にて摺動試験を行な
い、摩耗量及び接触抵抗を測定した処、下記の表
の右欄に示すような結果を得た。
試験条件
電 流：0.6A
電 圧：12V
負 荷：抵抗負荷
回転速度：1000回転／分
周 速：130〜120m／min
接触力：100g
試験時間：７時間
The present invention relates to improvements in sliding contact materials for brushes. Conventionally, various materials have been used as sliding contact materials, and in particular, Pd30 is the material for brush contacts.
Alloy materials consisting of ~70% by weight and 30-70% by weight of Ag were widely used. However, brush contacts made of this alloy material have poor abrasion resistance when sliding with the commutator, and tend to generate abrasion powder, which causes noise. The present invention has been made to eliminate such drawbacks, and provides a sliding contact material for brushes that uses the above-mentioned alloy material as a base material and has improved wear resistance by adding a small amount of a specific material to the alloy material. This is what we intend to provide. The sliding contact material for brushes of the present invention has a composition ratio of
Pd-Ag with Pd30~70wt% and Ag30~70wt%
92.0 to 98.9% by weight and the balance is Mn 1 to 5% by weight,
A total of 0.1 to 3.0 of at least one of Si, Bi, and Ge
% by weight. In the sliding contact material for brushes of the present invention, the Pd-Ag composition ratio is 30 to 70% by weight of Pd and 30 to 70% by weight of Ag.
is 92.0 to 98.9% by weight and the balance is Mn 1 to 5% by weight,
A total of 0.1 to 3.0 of at least one of Si, Bi, and Ge
The reason why it is expressed as % by weight is that in order to improve the wear resistance of the alloy material, Mn improves the melt flow during casting, and at least one of Si, Bi, and Ge refines the crystal grains. Here, Si,
Bi and Ge do not reduce the effects of each other, so they can be used alone or in combination of two or more. Furthermore, in order to increase the hardness by combining Mn with at least one of Si, Bi, and Ge in combination, it is possible to increase the hardness by adding 1% by weight of Mn or Si,
At least one of Bi and Ge is 0.1% by weight in total
If the Mn content is less than 5% by weight, the effect cannot be achieved.
Alternatively, if the total amount of at least one of Si, Bi, and Ge exceeds 3% by weight, the amount of oxides generated increases, contact resistance increases, and furthermore, it becomes unstable. Further, by setting the contents of Pd and Ag within a range that does not change the composition ratio of the conventional alloy material, the characteristics of the conventional alloy material can be exhibited without being impaired. Next, a conventional alloy material is used as a base material, and Mn and Mn are added to it.
By adding Si, a sliding contact material for a brush having the composition shown in Example 1 of the table was prepared, and a sliding contact material for a brush according to the present invention having the composition shown in the table and a conventional sliding contact for a brush were prepared in the same manner. Brush wire rods each having a wire diameter of 0.7 mm were made using the materials, and each of these was cut to a length of 8 mm.
Two pieces are placed in parallel and one end is 10mm wide, 13mm long, and thick.
A brush contact was made by welding to a 0.2 mm base material and bending a 2R arc-shaped contact part at the other end. Then, each brush contact was brought into contact with a disk-shaped commutator, and the commutator was rotated in forward and reverse directions to perform a sliding test under the following test conditions, and the amount of wear and contact resistance were measured. The results shown in the column were obtained. Test conditions Current: 0.6A Voltage: 12V Load: Resistance load Rotation speed: 1000 rotations/divided speed: 130 to 120m/min Contact force: 100g Test time: 7 hours
【表】
上記の表で明らかなように実施例１〜12の刷子
接点は従来例の刷子接点に比し摩耗量が著しく少
なく、接触抵抗が低く安定していることが判る。
これはひとえに実施例１〜12の刷子接点の刷子線
材を構成している本発明の刷子用摺動接点材料
が、MnとSi、Bi、Geの少なくとも一種を添加す
ることによつて硬くなり、耐摩耗性が向上するか
らに他ならない。
以上詳記した通り本発明による刷子用摺動接点
材料によれば、従来の刷子用摺動接点材料に比べ
著しく耐摩耗性に優れ、摩耗粉の発生量が極めて
少なくて、ノイズの発生が殆んど無く、また従来
の刷子用摺動接点材料による場合より低く安定し
た接触抵抗を有する刷子接点を得ることができる
という効果がある。[Table] As is clear from the above table, the brush contacts of Examples 1 to 12 have significantly less wear than the conventional brush contacts, and it can be seen that the contact resistance is low and stable.
This is because the brush sliding contact material of the present invention, which constitutes the brush wire of the brush contacts of Examples 1 to 12, becomes hard by adding Mn and at least one of Si, Bi, and Ge. This is because it improves wear resistance. As detailed above, the sliding contact material for brushes according to the present invention has significantly superior wear resistance compared to conventional sliding contact materials for brushes, generates extremely little wear powder, and hardly generates noise. There is an effect that it is possible to obtain a brush contact having a lower and more stable contact resistance than when using conventional sliding contact materials for brushes.