JPS59216445A - Current collector of rotary electric machine - Google Patents

Abstract

PURPOSE:To reduce the polarity difference of a brush wear amount by covering at least one contact slide surfaces of a current collecting ring and a brush with an oxidation resistant conductive ceramic material. CONSTITUTION:An oxidation resistant conductive ceramic cylinder ll is provided on the outer periphery of a current collecting ring 3, i.e., the sliding surface with a brush. The central side of a rotational shaft l from the cylinder ll is formed of a metal material cylinder 12 of copper, iron or steel, shrink-fitted through an insulating cylinder 2 to the shaft l, and electrically connected to lead wire 8 in the electrically insulating state from the shaft l via an insulating bolt 13 at one end of the cylinder 12.

Description

【発明の詳細な説明】 〔発明の利用分野〕 本発明は回転電機の集電装置に係シ、特に集電環、ブラ
シおよび保持装置等を有する回転電機の集電装置に関す
るものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a current collector for a rotating electric machine, and more particularly to a current collector for a rotating electric machine having a current collecting ring, a brush, a holding device, and the like.

〔発明の背景〕[Background of the invention]

通常、発電装置や電気を動力として用いる電気機械装置
では回転界磁型交流発電機における界磁電流の供給、回
転電機子型直流電動機における電機子離流の供給、電車
における駆動電力の供給等静止体から回転あるいは直線
運動体内部に一流や電力を供給する所謂集電装置を必要
とする場合が多い。そしてこのような集電装置として回
転トランス等を用いる電気式のものと、運動体側と静止
体側との夫々に装備された電極を機械的に接触。Normally, power generation devices and electromechanical devices that use electricity as motive power are stationary, such as supplying field current in rotating field type alternating current generators, supplying armature separation in rotating armature type DC motors, and supplying driving power in electric trains. In many cases, a so-called current collector is required to supply current or electric power from the body to the interior of the rotating or linearly moving body. Then, such a current collector is an electric type using a rotating transformer, etc., and the electrodes installed on the moving body side and the stationary body side are brought into mechanical contact.

摺動させこの摺動面を電気接点として一流の授受を行な
う機械式のものとがあるが、構造が簡単で安価であると
いう点から機械式の装置がより多く用いられていること
は周知の通シである。There are mechanical devices that use the sliding surface as an electrical contact to perform first-class transmission and reception, but it is well known that mechanical devices are more commonly used because they have a simple structure and are inexpensive. It is common knowledge.

ところでこの機械式の集電装置では運動方向に連続的に
形成される電極（以下、集電環と称す）と、これと接触
摺動する局所的に配備された電極（以下、ブラシと称す
）との摺動面を電気接点として両者間を電気的に接続す
るものであるから、集電環とブラシとの摺動状態が集電
装置としての性能および信頼性に非常に大きな影響を及
ぼす。By the way, this mechanical current collector has an electrode that is continuously formed in the direction of movement (hereinafter referred to as a current collection ring) and an electrode that is locally arranged to slide in contact with the electrode (hereinafter referred to as a brush). Since the sliding surface between the current collecting ring and the brush is used as an electrical contact point to electrically connect the two, the sliding condition between the current collecting ring and the brush has a very large effect on the performance and reliability of the current collecting device.

また機械的な摺動面を有しており長時間運転する集電装
置では集電環およびプランの摩耗が生じるので、定期的
にこれら部品を交換することが必要である。従ってこの
種集電装置では摺動状態や摩耗状況を常に監視し、必要
に応じて摺動状態の調整や集電環の修正加工あるいはブ
ラシの交換が必要である等保守の繁雑な事が欠点であり
、以前から保守性を向上させるだめの種々の改良が行な
われてきた。例えば修正加工や交換に手間のかかる運動
体側の集電環材料として銅、鋼および鉄等の摩耗し難い
金属材料を用い、静止側のブラシ材料として金属材料よ
りも摩耗し易いカーボン（炭素）や銅−カーボン材を用
いたり、ブラシを適度な押圧力で弾性保持するブラシ保
持装置の改良による摺動安定性の向上等が図られてきた
。Furthermore, in a current collector that has a mechanical sliding surface and is operated for a long time, the current collection ring and plan wear out, so it is necessary to replace these parts periodically. Therefore, this type of current collector requires constant monitoring of the sliding condition and wear condition, and as necessary, adjusting the sliding condition, modifying the current collecting ring, or replacing the brushes.The disadvantage is that maintenance is complicated. Various improvements have been made to improve maintainability. For example, metal materials such as copper, steel, and iron that are hard to wear are used as the collector ring material on the moving body side, which requires time and effort to modify or replace, and carbon, which wears more easily than metal materials, is used as the brush material on the stationary side. Efforts have been made to improve sliding stability by using copper-carbon materials and by improving brush holding devices that elastically hold brushes with appropriate pressing force.

しかし機械的摺動現象は摺動速度や通電電流の値等によ
って微妙に変化する複雑な現象であり、現在においても
さらに改善すべき問題が幾つか残されている。その一つ
に直流電流の授受を行なう正負一対の摺動面の集電特性
に極性差が生ずる、すなわち集電環とブラシとの摺動面
を通過する電流方向によって接触摺動面の電気抵抗（従
って電圧降下）、摩擦係数およびブラシ摩耗量等が顕著
に異なる問題がある。そしてこの極性差の問題は、適用
対象となる電気機械装置によって集電装置に要求される
機能や構成が変っても、集電環として銅、鉄および鋼等
の金属を用い、ブラシとしてカーボンまたは銅−カーボ
ン系材料を用いる従来装置のすべてに共通する欠点とし
てその改善が望まれていた。However, the mechanical sliding phenomenon is a complex phenomenon that changes subtly depending on the sliding speed, the value of the applied current, etc., and even now there are still some problems that need to be improved. One of these is the polarity difference that occurs in the current collection characteristics of the pair of positive and negative sliding surfaces that transfer direct current, that is, the electrical resistance of the contact sliding surface depends on the direction of the current passing through the sliding surface between the current collection ring and the brush. There is a problem that the friction coefficient (therefore, the voltage drop), the friction coefficient, the amount of brush wear, etc. are significantly different. The problem with this polarity difference is that even if the function and configuration required of the current collector change depending on the electromechanical device to which it is applied, metals such as copper, iron, and steel are used as the current collection ring, and carbon or carbon as the brush. It has been desired to improve the shortcomings common to all conventional devices using copper-carbon based materials.

このような極性差の発生例とこれによる弊害とについて
、第１図および第２図に示されている代表的な集電装置
を例にとって次に説明する。第１図にはタービン発電機
の回転子巻線（界磁巻線）に直流励磁電流を供給する集
電装置が示されている。同図に示されているように集電
装置は発電機の回転軸１の軸端部に絶縁円筒２ａ、２ｂ
を介して焼嵌めされた一対の集電環３ａ、３ｂの外周に
複数個に分割されたブラシ４　（４ａ、４ｂ）が接触摺
動している。この上うな集電装置では図中に実線の矢印
で示されているように別置の直流電源（図示せず）の高
電位側に接続される端子５ｂから電流リード６ｂ、ブラ
シ４ｂ、摺動面７ｂ、集電ｉ３ｂ、電流リード８ｂ９発
電機回転子巻線（図示せず）、電流リード８ａ、集電環
３ａｙ摺動面７ａ、ブラシ４ａ、電流リード６ａ、別置
の直流電源の低電位側に接続される端子５ａの順の経路
で励磁電流の供給が行なわれる。この場合に通常一般に
は第２図に示されているように摺動面７ａ、７ｂを通過
する電流Ｉが図中に実線矢印表示のブラシ４ａ、４ｂか
ら集電環３ａ、３ｂ側に流れる場合（第１図に示した集
電装置の右半分）を正（＋）極、その逆の図中に点線矢
印表示の場合（第１図に示した集電装置の左半分）を負
←）極と称するのが普通であり、また図示例のように正
。An example of the occurrence of such a polarity difference and the adverse effects caused by it will be described below using a typical current collector shown in FIGS. 1 and 2 as an example. FIG. 1 shows a current collector that supplies DC excitation current to a rotor winding (field winding) of a turbine generator. As shown in the figure, a current collector is provided with insulating cylinders 2a and 2b at the end of the rotating shaft 1 of the generator.
A plurality of brushes 4 (4a, 4b) divided into a plurality of parts slide in contact with the outer periphery of a pair of current collector rings 3a, 3b that are shrink-fitted through the ring. In this type of current collector, as shown by the solid arrow in the figure, a current lead 6b, a brush 4b, and a slider are connected from a terminal 5b connected to the high potential side of a separate DC power supply (not shown) to a current lead 6b, a brush 4b, and a sliding wire. Surface 7b, current collector i3b, current lead 8b9, generator rotor winding (not shown), current lead 8a, current collector ring 3ay sliding surface 7a, brush 4a, current lead 6a, low potential of separate DC power supply The excitation current is supplied through a path in the order of the terminals 5a connected to the side. In this case, generally, as shown in FIG. 2, when the current I passing through the sliding surfaces 7a and 7b flows from the brushes 4a and 4b indicated by solid line arrows in the figure to the current collecting rings 3a and 3b. (The right half of the current collector shown in Figure 1) is the positive (+) pole, and the reverse (the left half of the current collector shown in Figure 1) is the negative (+) polarity. It is usually called a pole, and as shown in the example, it is positive.

負両極は軸方向にほぼ対称な構造に製作されるのが普通
である。そして集電環３ａ、３ｂとして銅。The negative poles are usually manufactured to have a substantially axially symmetrical structure. And copper is used as the current collecting rings 3a and 3b.

鉄および鋼等の金属材料が用いられてスリップリングと
称され、ブラシ４ａ、４ｂとしてカーボンまたは銅とカ
ーボンとの複合材料が用いられて電気ブラシと呼ばれる
ことが多いことも周知の通りである。なお図中３ａ’、
３ｂ’は摺動面に発生した金属酸化皮膜であり、９ａ、
９ｂはフ゛ラシ４ａ、４ｂを回転軸１と共に回動する集
電環３　ａ。It is also well known that metal materials such as iron and steel are used and are called slip rings, and the brushes 4a and 4b are made of carbon or a composite material of copper and carbon and are often called electric brushes. In addition, 3a' in the figure,
3b' is a metal oxide film generated on the sliding surface, 9a,
Reference numeral 9b denotes a current collecting ring 3a that rotates the brushes 4a, 4b together with the rotating shaft 1.

３ｂの外周面に適度な半径方向の押圧力で摺動自在に保
持する保持装置であり、図中矢印付点線は摺動面７ａ、
７ｂに発生する摺動摩擦損失や通電時の接触電気抵抗損
による集電装置の温度上昇を抑制するだめの冷却風の通
風経路であり　ｇ　ａ／。This is a holding device that slidably holds the outer circumferential surface of 3b with an appropriate radial pressing force, and dotted lines with arrows in the figure indicate sliding surfaces 7a,
This is a ventilation path for cooling air that suppresses the temperature rise of the current collector due to sliding friction loss occurring in the 7b and contact electrical resistance loss during energization.

９ｂ’はブスリングであり、ｉｏａ、ｉｏｂは集電環３
ａ、３ｂの外周部に設けた通風孔である。9b' is bus ring, ioa, iob are current collecting ring 3
This is a ventilation hole provided on the outer periphery of parts a and 3b.

ところで以上に説明した従来の集電装置では正極と負極
との寸法、形状を軸方向に対称に製作した場合でも、摺
動面７ａ、７ｂにおける発生損失（特に通電時の損失）
やブラシ４ａ、４ｂの摩耗量等に、程度の差はあるにし
ても殆んど例外なく無視できない極性差が生ずる。By the way, in the conventional current collector described above, even if the dimensions and shapes of the positive and negative electrodes are manufactured symmetrically in the axial direction, losses occur at the sliding surfaces 7a and 7b (especially losses during energization).
Even if there are differences in degree, there is almost always a non-ignorable polarity difference in the amount of wear of the brushes 4a, 4b, etc.

第３図および第４図には極性差に関する実験結果の一例
が示されている。集電環が銅製で、グラブが黒鉛質のカ
ーボン材の場合について横軸に摺動面におけるブラシの
平均電流密度δ（通電電流に対応）をとり、縦軸に摺動
面の摩擦係数μ（摩擦損失に対応）をとってブラシの平
均電流密度による摺動面の摩擦係数の変化特性が示され
ている第３図から明らかなように、正極Ｐ側と負極Ｑ側
との摩擦係数には差があり正極Ｐ側の方が負極Ｑ側より
も大きかった。摺動面の摩擦係数にこのような差が生じ
ると摺動面に発生する損失および摺動面の温度上昇にも
差が生じる。その結果、横軸にブラシの平均電流密度δ
をとり、縦軸にブラシの千時間当りの摩耗量ΔＬ　ｂ　
（ｒｔｕｎ／　１０３ｈ　ｒ　）をとってブラシの平均
電流密度によるブラシの摩耗量の変化特性が示されてい
る第４図のように、摺動摩擦力や摺動面の温度と密接な
関係があるブラシ（場合によっては集電環）の摩耗量に
も差が生じ、正極Ｐの方が負極Ｑよシ摩耗量が太きかっ
た。FIGS. 3 and 4 show examples of experimental results regarding polarity differences. When the collector ring is made of copper and the grab is made of graphite carbon material, the horizontal axis is the average current density δ (corresponding to the current flowing) of the brush on the sliding surface, and the vertical axis is the friction coefficient μ ( As is clear from Fig. 3, which shows the variation characteristics of the friction coefficient of the sliding surface depending on the average current density of the brush, the coefficient of friction between the positive electrode P side and the negative electrode Q side is There was a difference, and the positive electrode P side was larger than the negative electrode Q side. When such a difference occurs in the coefficient of friction of the sliding surfaces, a difference also occurs in the loss generated on the sliding surfaces and the temperature rise of the sliding surfaces. As a result, the average current density δ of the brush is shown on the horizontal axis
, and the vertical axis is the wear amount of the brush per 1,000 hours ΔL b
As shown in Figure 4, which shows the change in the amount of wear on the brush depending on the average current density of the brush, taking There was also a difference in the amount of wear on the collector ring (in some cases), with the positive electrode P having a greater amount of wear than the negative electrode Q.

このため集電環が高速回転する集電装置のようにブラシ
の摩耗が激しく、比較的短かい周期で取り替えが必要な
大型集電装置になると、摩耗量の極性差により両極Ｐ、
Ｑのブラシの交換周期に差が生じ、ブラシを摩耗限界ま
で効率よく使用しようとするとブラシの交換回数が増え
、逆に交換周期を同一にすると摩耗量の少ない極性側の
ブラシの利用効率が悪く、経済的でない欠点があった。For this reason, in large current collectors, such as those in which the current collecting ring rotates at high speed, where the brushes are worn heavily and must be replaced at relatively short intervals, the difference in the polarity of the amount of wear causes the two poles to
There is a difference in the replacement cycle of the Q brushes, and if you try to use the brushes efficiently to the limit of wear, the number of brush replacements will increase.On the other hand, if you keep the replacement cycles the same, the brushes on the polar side, which have less wear, will not be used efficiently. , there were disadvantages that were not economical.

このため大型タービン発電機等に供される大電流集電装
置のように一個（−極）の集電環外周に装備されるブラ
シの数が数１０個にも及び、その摩耗量監視や交換業務
が発電機保守業務中相当大きなウェイトを占めるもので
は、上述のような摩耗量の極性差による保守業務の繁雑
化が避けられなかった。For this reason, the number of brushes installed on the outer periphery of one (-pole) current collection ring, such as large current current collectors used in large turbine generators, etc., is up to several dozen, and the amount of wear must be monitored and replaced. If the work occupies a considerable portion of the generator maintenance work, it is inevitable that the maintenance work becomes complicated due to the polarity difference in the amount of wear as described above.

このようにブラシ摩耗量に極性差が生じるのは主として
集電環を形成する銅、鉄あるいは鋼等の金属材料原子と
周囲雰囲気中の酸素原子との酸化　　　　　　　　１反
応によって、集電環のブラシとの摺動接触面に形成され
る金属酸化皮膜の生成量および電気特性が電流通電方向
によって異なるだめであシ、集電環に銅、鉄あるいは鋼
等を使用している従来装置では避けられない問題であっ
た。This difference in polarity in the amount of brush wear is mainly due to the oxidation reaction between atoms of metal materials such as copper, iron, or steel that form the current collecting ring and oxygen atoms in the surrounding atmosphere. The amount of metal oxide film formed on the sliding contact surface and the electrical properties vary depending on the direction of current flow, which is unavoidable with conventional equipment that uses copper, iron, steel, etc. for the current collection ring. That was a problem.

〔発明の目的〕 本発明は以上の点に鑑みなされたものであシ、ブラシ摩
耗量の極性差の低減を可能とした回転電機の集電装置を
提供することを目的とするものである。[Object of the Invention] The present invention has been made in view of the above points, and an object of the present invention is to provide a current collector for a rotating electric machine that can reduce the polarity difference in the amount of brush wear.

〔発明の概要〕[Summary of the invention]

すなわち本発明は集電環およびブラシの少なくともいず
れか一方の接触摺動面が難酸化性の導電性セラミック材
で覆われていることを特徴とするものでちる。That is, the present invention is characterized in that the contact sliding surface of at least one of the current collecting ring and the brush is covered with an oxidation-resistant conductive ceramic material.

〔発明の実施例〕[Embodiments of the invention]

以下、図示した実施例に基づいて本発明を説明する。第
５図および第６図には本発明の一実施例が示されている
。なお従来と同じ部品には同じ符号を付したので説明を
省略する。本実施例では集電環３の外周部すなわちブラ
シとの摺動面に難酸化性の導電性セラミックの円筒体１
１を設けた。The present invention will be explained below based on the illustrated embodiments. An embodiment of the invention is shown in FIGS. 5 and 6. Note that parts that are the same as those in the conventional system are given the same reference numerals, and therefore their explanations will be omitted. In this embodiment, a cylindrical body 1 made of oxidation-resistant conductive ceramic is provided on the outer periphery of the current collector ring 3, that is, on the sliding surface with the brush.
1 was established.

このようにすることによりブラシと集電環３との接触摺
動面に金属酸化皮膜の生成を防止することができるよう
になり、ブラシ摩耗量の極性差の低減を可能とした回転
電機の集電装置を得ることができ／、５ すなわち難酸化性の導電性セラミックの円筒体１１より
も回転軸１の軸中心側は従来と同様銅。By doing this, it is possible to prevent the formation of a metal oxide film on the contact sliding surface between the brush and the current collector ring 3, and it is possible to reduce the polarity difference in the amount of brush wear. In other words, the center of the rotating shaft 1 is made of copper as in the conventional case, compared to the cylindrical body 11 made of oxidation-resistant conductive ceramic.

製 鉄おるいは鋼等の金属材戦９円筒体１２で形成しており
、回転軸１に絶縁円筒２を介して焼嵌めされ、円筒体１
２の一端で絶縁ボルト１３によって回転軸１と電気絶縁
状態を保ってリード線８と電気的に接続されている。ま
た導電性セラミックの円筒体１１と金属材料製の円筒体
１２とは両者の環状接触面３Ｃで電気的２機械的に接続
、連結されている。このように本実施例ではブラシとの
接触摺動が難酸化性の導電性セラミック製の円筒体１１
の外周面で行なわれる集電環構成として、集電環３とブ
ラシとの摺動面の酸化を防止するようにした。そして円
筒体１１を構成する難酸化性セラミック材料としては種
々考えられるが、炭化けい素粉末と安定化処理した硼化
金属粉末の混合体とを高温、高圧雰囲気中で焼結したセ
ラミック材が適している。特に硼化金属粉材料として硼
化ジルコニュームを用いた導電性セラミック材が、硼化
ジルコニュームの粉末の混合比を変えることによって導
電率を所望の値に選定することができ、十分な機械強度
が得られ、しかも摺動面温度として予想される６００か
ら８００Ｃ程度の高温に対しても酸化による金属酸化物
の皮膜形成を十分に防止することができるので非常に望
ましい材料であシ、本実施例ではこの材料で円筒体１１
を形成した。It is made of a metal material such as iron or steel and has a cylindrical body 12, which is shrink-fitted to the rotating shaft 1 via an insulating cylinder 2, and the cylindrical body 1 is
2 is electrically connected to the lead wire 8 at one end thereof by an insulating bolt 13 while maintaining an electrically insulated state from the rotating shaft 1. Further, the conductive ceramic cylinder 11 and the metal cylinder 12 are electrically and mechanically connected and coupled at their annular contact surface 3C. As described above, in this embodiment, the cylindrical body 11 made of oxidation-resistant conductive ceramic is used for sliding contact with the brush.
The current collecting ring is configured on the outer peripheral surface of the brush to prevent oxidation of the sliding surface between the current collecting ring 3 and the brush. Various oxidation-resistant ceramic materials are conceivable for forming the cylindrical body 11, but a ceramic material made by sintering a mixture of silicon carbide powder and stabilized metal boride powder in a high-temperature, high-pressure atmosphere is suitable. ing. In particular, conductive ceramic materials using zirconium boride as the metal boride powder material can have a desired electrical conductivity by changing the mixing ratio of the zirconium boride powder, and sufficient mechanical strength can be obtained. Moreover, it is a highly desirable material because it can sufficiently prevent the formation of a metal oxide film due to oxidation even at high temperatures of about 600 to 800 C, which is expected as the sliding surface temperature. Cylindrical body 11 with this material
was formed.

以上の実施例のブラシ摩耗量の極性差について従来の集
電装置を用いた場合と比較検討した。その検討結果は横
軸に運転時間をとり縦軸に正、負ブラシの摩耗差（摩耗
量の差）をとって、運転時間による正、負ブラシの摩耗
差が示されている第７図のように、実測値の平均値を外
挿し、直線Ｘで示した本実施例の集電装置の正、負ブラ
シの摩耗差は、実測値の平均値を外挿し、直線Ｙで示し
だ従来例の集電装置の摩耗差より小さくすぐれている。The polarity difference in the amount of brush wear in the above embodiments was compared with that in the case where a conventional current collector was used. The results of this study are shown in Figure 7, where the horizontal axis shows the operating time and the vertical axis shows the wear difference (difference in wear amount) between the positive and negative brushes. The wear difference between the positive and negative brushes of the current collector of this embodiment, which is shown by the straight line This is superior to the current collector wear difference.

このように導電性セラミック材を用いた場合はブラシの
摩耗粉の付着による境界層の生成等の影響で若干の極性
差が生じるが、従来の集電装置の場合に比べれば格段と
少なくなっており、ブラシ摩耗量の極性差の低減に十分
な効果を奏することが明らかである。これは摺動接触面
への金属酸化皮膜の生成が防止されるためである。When a conductive ceramic material is used in this way, a slight difference in polarity occurs due to the formation of a boundary layer due to the adhesion of abrasion powder from the brushes, but this is much smaller than in the case of conventional current collectors. It is clear that this method has a sufficient effect on reducing the polarity difference in the amount of brush wear. This is because formation of a metal oxide film on the sliding contact surface is prevented.

なおこの正、負ブラシの摩耗量の実験を通して円筒体１
１の摺動面の平滑度がブラシ摩耗の絶対値および摺動状
態に大きな影響を及ぼすことを別途明らかにし、本実施
例の集電装置では円筒体１１の摺動面を通常鏡面仕上げ
と称される平滑面に仕上げた。これにより本実施例の集
電装置では集電環３とブラシとの安定した摺動状態を維
持することが可能である。In addition, through this experiment on the amount of wear of the positive and negative brushes, the cylindrical body 1
It has been separately clarified that the smoothness of the sliding surface of the cylindrical body 11 has a large effect on the absolute value of brush wear and the sliding condition, and in the current collector of this embodiment, the sliding surface of the cylindrical body 11 is usually referred to as having a mirror finish. Finished with a smooth surface. As a result, in the current collector of this embodiment, it is possible to maintain a stable sliding state between the current collecting ring 3 and the brush.

第８図には本発明の他の実施例が示されている。Another embodiment of the invention is shown in FIG.

本実施例では集電環３を導電性セラミック材で一体的に
製作した。このようにすることにより銅。In this example, the current collecting ring 3 was integrally manufactured from a conductive ceramic material. Copper by doing this.

鉄、鋼等の金属材料を用いる従来の集電装置相当の導電
率を有するセラミック材の実現が困難なため、集電環部
の電流通過による発熱量（抵抗損）が多くなる欠点はあ
るが、極性差の低減については前述の場合と同様な効果
が得られるのみならず、構造が簡単になる。Although it is difficult to create a ceramic material with conductivity equivalent to that of conventional current collectors using metal materials such as iron and steel, there is a drawback that the amount of heat generated (resistance loss) due to the passage of current through the current collecting ring increases. In terms of reducing the polarity difference, not only the same effect as in the above case can be obtained, but also the structure becomes simpler.

なおこれら各実施例では集電環側の摺動面を導電性セラ
ミック材で形成した場合について説明したが、ブラシ材
として銅−カーボンを用いる場合にはブラシ側摺動面に
形成される金属酸化皮膜による極性差が生ずるので、こ
のような懸念のある場合には集電環およびブラシの両者
の摺動面を導電性セラミック材で形成することはいうま
でもない。In each of these examples, the case where the sliding surface on the current collector ring side is formed of a conductive ceramic material has been explained, but when copper-carbon is used as the brush material, metal oxide formed on the sliding surface on the brush side Since a polarity difference occurs due to the coating, it goes without saying that if there is such a concern, the sliding surfaces of both the current collection ring and the brush should be made of a conductive ceramic material.

〔発明の効果〕〔Effect of the invention〕

上述のように本発明は集電環とブラシとの接触摺動面に
金属酸化皮膜が発生しないようにしたので、接触摺動面
に金属酸化皮膜が発生しないようになって、ブラシ摩耗
量の極性差を減少することができるようになり、ブラシ
摩耗量の極性差の低減を可能とした回転電機の集電装置
を得ることができる。As described above, the present invention prevents the formation of a metal oxide film on the contact sliding surface between the current collector ring and the brush, which prevents the formation of a metal oxide film on the contact sliding surface and reduces the amount of brush wear. It is now possible to reduce the polarity difference, and thus it is possible to obtain a current collector for a rotating electric machine that can reduce the polarity difference in the amount of brush wear.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は従来の回転電機の集電装置の縦断側面図、第２
図は従来の回転電機の集電装置の接触摺動面間りの拡大
横断面図、第３図は従来の回転電機の集電装置のブラシ
の平均電流密度による摺動面の摩擦係数の変化特性図、
第４図は従来の回転電機の集電装置のブラシの平均電流
密度によるブランの摩耗量の変化特性図、第５図は本発
明の回転電機の集電装置の一実施例の集電装置要部の縦
断側面図、第６図は第５図のＡ−Ａ線に沿う断面図、第
７図は本発明の回転電機の集電装置の一実施例の運転時
間による正、負ブラシの摩耗差の変化特性図、第８図は
本発明の回転電機の集電装置の他の実施例の第６図相当
の断面図である。 １・・・回転軸、２，２ａ、２ｂ・・・電気的絶縁体（
絶縁円筒）、３．３　ａ、　３　ｂ・・・集電環、４，
４ａ。 ４　ｂ−・・ブラシ、７ａ、７ｂ−・・摺動面、９ａ、
９ｂ・・・保持装置、１１・・・難酸化性の導電性セラ
ミック第１　図 第２図 第　３　口 第４　口 フ゛ラシのヂ均電）丸寥１１　Ｊ（’／ｃｍす第５図 ご 第６図 ＩFigure 1 is a longitudinal cross-sectional side view of a current collector for a conventional rotating electrical machine;
The figure is an enlarged cross-sectional view of the contact sliding surfaces of the current collector of a conventional rotating electric machine, and Figure 3 shows the change in the friction coefficient of the sliding surface depending on the average current density of the brush of the current collector of a conventional rotating electric machine. Characteristic diagram,
FIG. 4 is a characteristic diagram of the change in the amount of wear of the brush depending on the average current density of the current collector of a conventional rotating electric machine, and FIG. FIG. 6 is a cross-sectional view taken along the line A-A in FIG. 5, and FIG. 7 shows wear of the positive and negative brushes depending on operating time of an embodiment of the current collector for a rotating electric machine of the present invention. The difference change characteristic diagram, FIG. 8, is a sectional view corresponding to FIG. 6 of another embodiment of the current collector for a rotating electric machine according to the present invention. 1... Rotating shaft, 2, 2a, 2b... Electrical insulator (
(insulating cylinder), 3.3 a, 3 b... current collector ring, 4,
4a. 4 b--Brush, 7a, 7b--Sliding surface, 9a,
9b... Holding device, 11... Oxidation-resistant conductive ceramic (Figure 1) Figure 2 Figure 3 Figure 4 Figure 4 Figure 6 I

Claims (1)

【特許請求の範囲】 １、回転軸に電気的絶縁体を介して嵌合固定され、前記
回転軸と共に回動する集電環と、との集電環と接触摺動
するブラシと、このブラシを前記集電環の外周に摺動自
在に保持する保持装置とを備え、前記集電環と前記ブラ
シとの接触摺動面を介して電流の授受が行なわれる回転
電機の集電装置において、前記集電環および前記ブラフ
の少なくともいずれか一方の前記接触摺動面が難酸化性
の導電性セラミック材で覆われていることを特徴とする
回転電機の集電装置。 ２、前記導電性セラミック材が、安定化処理した炭化け
い素粉床と硼化ジルコニューム粉末との混合粉末の高温
焼結材である特許請求の範囲第１項記載の回転電機の集
電装置。[Scope of Claims] 1. A current collector ring that is fitted and fixed to a rotating shaft via an electrical insulator and rotates together with the rotating shaft; a brush that slides in contact with the current collecting ring; and this brush. A current collector for a rotating electrical machine, comprising: a holding device that slidably holds the current collector ring on the outer periphery of the current collector ring, and in which current is delivered and received through a contact sliding surface between the current collector ring and the brush, A current collector for a rotating electric machine, wherein the contact sliding surface of at least one of the current collecting ring and the bluff is covered with an oxidation-resistant conductive ceramic material. 2. The current collector for a rotating electric machine according to claim 1, wherein the conductive ceramic material is a high-temperature sintered material of a mixed powder of a stabilized silicon carbide powder bed and zirconium boride powder.