【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、Pd30〜50重量
％、Ag20〜40重量％、Cu20〜40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、接触抵
抗が高く不安定であつた。
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、耐摩耗性及び接触抵抗特性を向上させ
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
Pd30〜50重量％、Ag20〜40重量％、Cu20〜40重
量％のPd−Ag−Cuが95〜99.5重量％及び残部が
Ｂ及びTlの少なくとも一種を合計で0.5〜５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Pd30〜50重量％、Ag20〜40重量％、Cu20〜40
重量％のPd−Ag−Cuが95〜99.5重量％及び残部
がＢ及びTlの少なくとも一種を合計で0.5〜５重
量％としている理由は、前記従来の合金材料の耐
摩耗性及び接触抵抗特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、Ｂ及びTl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、Ｂ及びTlのうち少なくとも一種を合
計で５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、Ag、Cu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Ｂ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, as sliding contact materials for brushes, materials with excellent hardness, corrosion resistance, spring properties, etc., such as Pd 30 to 50% by weight, Ag 20 to 40% by weight, Cu20 Alloy materials consisting of ~40% by weight were widely used. However, brush contacts made of this alloy material had poor wear resistance during sliding with the commutator, high contact resistance, and were unstable. The present invention has been made to eliminate such drawbacks, and uses the above-mentioned alloy material as a base material, adds a small amount of a specific element to it, uses the generated oxide as a lubricant, and improves wear resistance and contact resistance. It is an object of the present invention to provide a sliding contact material for brushes with improved resistance characteristics. The sliding contact material for brushes of the present invention has a composition ratio of
It consists of 95-99.5% by weight of Pd-Ag-Cu of 30-50% by weight, 20-40% by weight of Ag, 20-40% by weight of Cu, and the balance is 0.5-5% by weight in total of at least one of B and Tl. be. In the sliding contact material for brushes of the present invention, the composition ratio is 30 to 50% by weight of Pd, 20 to 40% by weight of Ag, and 20 to 40% by weight of Cu.
The reason why Pd-Ag-Cu is 95 to 99.5% by weight and the balance is at least one of B and Tl is 0.5 to 5% by weight in total is that the wear resistance and contact resistance characteristics of the conventional alloy materials are improved. This is to generate an appropriate amount of oxide that becomes a lubricant in order to improve the quality of B If the total amount of at least one of Tl and Tl exceeds 5% by weight, the amount of oxides generated will increase, the contact resistance will be high and unstable, and the spring properties will deteriorate. Furthermore, by setting the contents of Pd, Ag, and Cu 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 B 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/divided speed: 130-120m/min Contact force: 100g Test time: 7 hours
【表】
上記の表で明らかなように実施例１〜９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１〜９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Ｂ、Tl等の酸化物を発生し、この
酸化物が潤滑剤となり、耐摩耗性及び接触抵抗特
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 9 had significantly less wear than the conventional brush contacts, and it was found that the contact resistance was 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 9, generates oxides such as B and Tl during sliding, and these oxides act as lubricants. 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.