【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、とりわけ刷子用摺動接点材料としては、硬
さ、耐蝕性、ばね性等の優れた、Pd87〜93重量
％、Ru7〜13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
の元素を僅かに添加させて、発生する酸化物を潤
滑剤とし、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
Pd87〜93重量％、Ru7〜13重量％のPd−Ruが95
〜99.5重量％及び残部がIn、Ba及びCdの少なく
とも一種を合計で0.5〜７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Pd87〜93重量％、Ru7〜13重量％のPd−Ruが
93〜99.5重量％及び残部がIn、Ba及びCdの少な
くとも一種を合計で0.5〜７重量％としている理
由は、前記従来の合金材料の耐摩耗性を向上すべ
く潤滑剤となる酸化物を適量発生させる為で、
In、Ba及びCdのうち少なくとも一種を合計で0.5
重量％未満では酸化物の発生量が少なくて潤滑剤
としての効果を発揮できず、In、Ba及びCdのう
ち少なくとも一種を合計で７重量％を超えると酸
化物の発生量が多くなり、接触抵抗が高く不安定
となり、その上ばね性が劣化するものである。
またPd、Ru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
発揮されることとなるものである。
次に従来の合金材料を基材とし、これにIn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：直流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, sliding contact materials for brushes are made of Pd 87-93% by weight and Ru 7-13% by weight, which have excellent hardness, corrosion resistance, spring properties, etc. Alloy materials were widely used. However, brush contacts made of this alloy material have poor abrasion resistance when sliding with the commutator, and are likely to generate abrasion powder, causing noise. The present invention was made in order to eliminate such drawbacks, and uses the above-mentioned alloy material as a base material and adds a small amount of a specific element to it, and uses the generated oxide as a lubricant to improve wear resistance. It is an object of the present invention to provide a sliding contact material for a brush that has a high quality. The sliding contact material for brushes of the present invention has a composition ratio of
Pd-Ru with 87-93 wt% Pd and 7-13 wt% Ru
-99.5% by weight, and the balance consists of a total of 0.5 to 7% by weight of at least one of In, Ba and Cd. In the sliding contact material for brushes of the present invention, Pd-Ru has a composition ratio of 87 to 93% by weight of Pd and 7 to 13% by weight of Ru.
The reason why the proportion is 93 to 99.5% by weight and the balance is 0.5 to 7% by weight in total of at least one of In, Ba, and Cd is that an appropriate amount of oxide as a lubricant is added to improve the wear resistance of the conventional alloy material. In order to cause
A total of 0.5 of at least one of In, Ba and Cd
If the total content of at least one of In, Ba, and Cd exceeds 7% by weight, the amount of oxides generated will increase and the lubricant will not be effective as a lubricant. The resistance is high and unstable, and the spring properties are deteriorated. Furthermore, by setting the contents of Pd and Ru 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 In is added thereto to obtain a brush sliding contact material having the composition shown in Example 1 in the table. Brush wires with a wire diameter of 0.7 mm were made using the sliding contact material and the conventional sliding contact material for brushes, each was cut to a length of 8 mm, and two wires were placed in parallel with one end having a width of 10 mm and a length of 13 mm. A brush contact was made by welding to a 0.2 mm thick 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 wear amount and contact resistance were measured. The results shown in the column were obtained. Test conditions Current: DC 0.6A Voltage: 12V Load: Resistance load Rotation speed: 1000 rotations/division 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１〜18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１〜18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、摺動時にIn、Ba、Cd等の酸化物を発生し、
この酸化物が潤滑剤となり、また、酸化物が軟ら
かい為、摺動作用により容易に除去されるので、
耐摩耗性、接触抵抗特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、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も低く安定し
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 18 have significantly less wear compared to the conventional brush contacts, and it can be seen that the contact resistance is low and stable.
This is simply due to the fact that the brush sliding contact material of the present invention, which constitutes the brush wire of the brush contacts of Examples 1 to 18, generates oxides such as In, Ba, and Cd during sliding.
This oxide acts as a lubricant, and since it is soft, it is easily removed by sliding action.
This is because the wear resistance and contact resistance characteristics are improved. 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 generates almost no noise. This has the advantage that it is possible to obtain a brush contact having a lower and more stable contact resistance than when using conventional brush contact materials.