JP2004068999A

JP2004068999A - Electrode for electromagnetic clutch

Info

Publication number: JP2004068999A
Application number: JP2002232032A
Authority: JP
Inventors: Masazumi Ishikawa; 石川　正純; Hideyuki Gonda; 権田　英之
Original assignee: Sanden Corp
Current assignee: Sanden Corp
Priority date: 2002-08-08
Filing date: 2002-08-08
Publication date: 2004-03-04

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrode for an electromagnetic clutch comprising two of conventional electrodes for electromagnetic clutches provided with a circular plate and an electrode part in slide contact with the circular plate, restricting deterioration of life of a bearing compared to conventional electrodes for electromagnetic clutches, and shortening axial length of the electromagnetic clutches compared to a case for electric connection to a positive electrode and a negative electrode in an electromagnetic coil. <P>SOLUTION: The electrode for the electromagnetic clutch is for energizing the electromagnetic coil in the electromagnetic clutch. It is provided with a first electrode provided with the circular plate and an electrode part in slide contact with the circular plate to be electrically connected to either the positive electrode or the negative electrode in the electromagnetic coil without forming a bearing, and a second electrode provided with an outer race for the bearing, an inner race for the bearing, and a plurality of rows of rolling bodies held between the outer race and the inner race to be electrically connected to the other of the positive electrode and the negative electrode of the electromagnetic coil. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は電磁クラッチ用電極に関するものである。
【０００２】
【従来の技術】
駆動源により回転駆動される磁性材料製の回転部材と、前記回転部材を従動側機器のハウジングに対して回転可能に支持する軸受と、前記回転部材と一体的に回転し通電により前記回転部材を磁化させる電磁コイルと、従動側機器に固定されると共に前記回転部材に対向して配設され、磁化された前記回転部材に吸着されるアーマチュアとを備える電磁クラッチの前記電磁コイルに通電するための電磁クラッチ用電極であって、前記軸受のアウターレースと、前記軸受のインナーレースと、アウターレースとインナーレースとに挟まれた一列の転動体とを有し、電磁コイルの正極に電気的に接続される第１電極と、前記軸受のアウターレースと、前記軸受のインナーレースと、アウターレースとインナーレースとに挟まれた一列の転動体とを有し、第１電極に対して絶縁され、電磁コイルの負極に電気的に接続される第２電極とを備える電磁クラッチ用電極が、特開平１０−２８１１８１号公報に開示されている。
特開平１０−２８１１８１号の電磁クラッチ用電極を使用すると、円環板と円環板に摺接する電極部品とを備える従来の電磁クラッチ用電極を軸方向に二つ並べて配設し、電磁コイルの正極と負極とに電気的に接続する場合に比べて、電磁クラッチの軸方向長さが短縮されるという利点が得られる。
【０００３】
【発明が解決しようとする課題】
特開平１０−２８１１８１号公報の電磁クラッチ用電極には、一列の転動体を介して電磁コイルに電流が流入し、一列の転動体を介して電磁コイルから電流が流出するので、転動体の電食が激しく、軸受の寿命が顕著に低下するという問題がある。
本発明は上記問題に鑑みてなされたものであり、特開平１０−２８１１８１号公報の電磁クラッチ用電極に比べて軸受の寿命低下が抑制され、且つ円環板と円環板に摺接する電極部品とを備える従来の電磁クラッチ用電極を二つ軸方向に並べて配設し、電磁コイルの正極と負極とに電気的に接続する場合に比べて比べて電磁クラッチの軸方向長さを短縮できる電磁クラッチ用電極を提供することを目的とする。
【０００４】
【課題を解決するための手段】
上記課題を解決するために、本発明においては、駆動源により回転駆動される磁性材料製の回転部材と、前記回転部材を従動側機器のハウジングに対して回転可能に支持する軸受と、前記回転部材と一体的に回転し通電により前記回転部材を磁化させる電磁コイルと、従動側機器に固定されると共に前記回転部材に対向して配設され、磁化された前記回転部材に吸着されるアーマチュアとを備える電磁クラッチの前記電磁コイルに通電するための電磁クラッチ用電極であって、円環板と円環板に摺接する電極部品とを備え電磁コイルの正極又は負極の何れか一方に電気的に接続され且つ軸受を形成しない第１電極と、前記軸受のアウターレースと、前記軸受のインナーレースと、アウターレースとインナーレースとに挟まれた複数列の転動体とを備え、電磁コイルの正極又は負極の何れか他方に電気的に接続される第２電極とを備えることを特徴とする電磁クラッチ用電極を提供する。
本発明に係る電磁クラッチ用電極においては、軸受が形成する第２電極は、電磁コイルの正極又は負極の何れか一方にのみ電気的に接続される。軸受は複数列の転動体を有しているので、当該複数列の転動体を介して電磁コイルに電流が流れ、或いは電磁コイルから電流が流れても、一列の転動体を流れる電流値は特開平１０−２８１１８１号公報の電磁クラッチ用電極に比べて少ない。この結果転動体の電食が抑制され、特開平１０−２８１１８１号公報の電磁クラッチ用電極に比べて軸受の寿命低下が抑制される。他方、円環板と円環板に摺接する電極部品とを備える第１電極は、電磁コイルの正極又は負極の何れか一方のみに電気的に接続されるので、当該電極の数は１で良い。この結果、円環板と円環板に摺接する電極部品とを備える従来の電磁クラッチ用電極を、軸方向に二つ並べて配設し、電磁コイルの正極と負極とに電気的に接続する場合に比べて比べて電磁クラッチの軸方向長さが短縮される。
【０００５】
本発明の好ましい態様においては、前記軸受のアウターレースとインナーレースとに挟まれた転動体を除く前記軸受の構成部材を介して、アウターレースとインナーレースとが電気的に導通する。
転動体を除く軸受の構成部材を介して、アウターレースとインナーレースとが電気的に導通すれば、転動体を流れる電流が減少し、転動体の電食が更に抑制され、軸受の寿命低下が更に抑制される。
前記構成部材は、アウターレースの内周面とインナーレースの外周面とに形成された周溝に嵌合した環状部材でも良く、転動体の保持器でも良く、アウターレース及び／又はインナーレースに形成された突起でも良く、防塵用シール部材でも良い。環状部材は自らの弾性力によりアウターレースの内周面とインナーレースの外周面とに形成された周溝に押し付けられるのが、良好な導通を確保する観点から望ましい。防塵用シール部材は自らの弾性力によりアウターレースの内周面とインナーレースの外周面とに押し付けられるのが、良好な導通を確保する観点から望ましい。
【０００６】
本発明の好ましい態様においては、転動体は絶縁材で形成され又は絶縁材で被覆されている。
転動体を除く軸受の構成部材のみで、アウターレースとインナーレースとを電気的に導通させれば、転動体の電食を完全に防止することができ、転動体の電食による軸受の寿命低下を完全に防止することができる。
【０００７】
本発明の好ましい態様においては、前記軸受のアウターレースとインナーレースとに挟まれた複数列の転動体中の何れか一列が導電体で形成され、他列の転動体は絶縁材で形成され或いは絶縁材で被覆されている。
複数列の転動体中の絶縁体で形成され或いは絶縁体で被覆された転動体の列は通電されず電食しない。電食しない転動体が存在するので、特開平１０−２８１１８１号公報の電磁クラッチ用電極に比べて軸受の寿命低下が抑制される。
【０００８】
【発明の実施の形態】
本発明の実施例に係る電磁クラッチ用電極を説明する。
図１に示すように、本実施例に係る電極が組み込まれた電磁クラッチは、図示しない駆動源により軸線Ｘ回りに回転駆動される磁性材料製のローター１と、ローター１に固定されローター１と一体的に回転し通電によりローター１を磁化させる電磁コイル２と、軸線Ｘ回りに回転可能な図示しない従動側機器の回転軸に固定されると共にローター１に対向して配設され、磁化されたローター１に吸着されるアーマチュア３とを備えている。ローター１は、軸受４を介して、従動側機器の図示しないハウジングによって、軸線Ｘ回りに回転可能に支持されている。
【０００９】
ローター１の端面に固定された絶縁材から成る円環部材５の内周面に、周溝５ａが形成されている。
従動側機器のハウジングに固定された絶縁材から成る円環部材６の外周面に、周溝５ａに対峙して、周溝６ａが形成されている。
図１、２に示すように、内側スリップリング７が、周溝６ａに嵌合固定されている。内側スリップリング７の外周面に、周溝７ａが形成されている。内側スリップリング７は、従動側機器から延びるリード線８に接続されている。
外側スリップリング９が、周溝５ａに嵌合固定されている。外側スリップリング９の内周面に、周溝９ａが形成されている。外側スリップリング９は、リード線１０を介して、電磁コイル２の正極側の巻線端部に接続されている。
内側スリップリング７と外側スリップリング９とに挟まれて、止め輪状の電極部品１１が配設されている。電極部品１１の外周部は、外側スリップリング９の周溝９ａに嵌合し、周溝９ａの底面と側面とに摺接している。電極部品１１の径方向内側へ折り返された両端部１１ａの内周部は、内側スリップリング７の周溝７ａに嵌合し、周溝７ａの底面と側面とに摺接している。
円環部材５、６、スリップリング７、９、電極部品１１により、第１電極が形成されている。
【００１０】
軸受４は、図１、３に示すように、ローター１に固定されたアウターレース４ａと、従動側機器のハウジングに固定されたインナーレース４ｂと、アウターレース４ａとインナーレース４ｂとに挟まれた２列の転動体４ｃ、４ｄとを備えている。アウターレース４ａは電磁コイル２の負極側の巻線端部に電気的に導通している。インナーレース４ｂは従動側機器を介してアースされている。
アウターレース４ａの内周面に周溝４ａ′が形成され、インナーレース４ｂの外周面に周溝４ｂ′が形成されている。止め輪状の電極部品１２の外周部が、アウターレースの周溝４ａ′に嵌合し、周溝４ａ′の底面と側面とに摺接している。電極部品１２の径方向内側へ折り返された両端部１２ａの内周部は、インナーレースの周溝４ｂ′に嵌合し、周溝４ｂ′の底面と側面とに摺接している。電極部品１２は自らの弾性力により、周溝４ａ′、４ｂ′に押し付けられている。
軸受４により第２電極が形成されている。
【００１１】
上記電磁クラッチにおいては、図示しない外部駆動原によってローター１が回転駆動されると、外側スリップリング９がローター１と一体的に回転する。電極部品１１が、回転している外側スリップリング９と停止している内側スリップリング７とに摺接することにより、外側スリップリング９と内側スリップリング７とが電気的に導通する。この結果、第１電極を介して、従動側機器から電磁コイル２に電流が流れる。
電磁コイル２から流出する電流は、軸受４のアウターレース４ａから転動体４ｃ、４ｄと電極部品１２とを通って、軸受４のインナーレース４ｂへ流れ、従動側機器を通ってアースされる。
【００１２】
本実施例に係る電磁クラッチ用電極においては、軸受４が形成する第２電極は、電磁コイル２の負極にのみ電気的に接続される。軸受は２列の転動体４ｃ、４ｄを有しているので、当該２列の転動体４ｃ、４ｄを介して電磁コイル２から従動側機器へ電流が流れても、各一列の転動体４ｃ、４ｄを流れる電流値は特開平１０−２８１１８１号公報の電磁クラッチ用電極に比べて少ない。この結果転動体４ｃ、４ｄの電食が抑制され、特開平１０−２８１１８１号公報の電磁クラッチ用電極に比べて軸受４の寿命低下が抑制される。電極部品１２を介しても、電磁コイル２から従動側機器へ電流が流れるので、転動体４ｃ、４ｄを流れる電流値が更に減少し、転動体４ｃ、４ｄの電食が更に抑制され、軸受４の寿命低下が更に抑制される。他方、円環部材５、６とスリップリング９、７を介して円環部材５、６に摺接する電極部品１１とを備える第１電極は、電磁コイル２の正極のみに電気的に接続されるので、当該電極の数は１で良い。この結果、円環板と円環板に摺接する電極部品とを備える従来の電磁クラッチ用電極を軸線Ｘ方向に二つ並べて配設し、電磁コイル２の正極と負極とに電気的に接続する場合に比べて電磁クラッチの軸方向長さが短縮される。
電極部品１２は自らの弾性力により、周溝４ａ′、４ｂ′に押し付けられているので、電極部品１２と周溝４ａ′、４ｂ′との摺接が安定し、電極部品１２を介するアウターレース４ａとインナーレース４ｂとの電気的導通が安定する。
【００１３】
電極部品１２に代えて、図４に示すように転動体４ｃ、４ｄの保持器４ｅに形成した突起４ｅ′をアウターレース４ａとインナーレース４ｂとに摺接させて両者間の電気的導通を図っても良く、図５に示すようにインナーレース４ｂに形成した突起４ｂ′をアウターレース４ａに摺接させて両者間の電気的導通を図っても良く、或いはアウターレース４ａに形成した突起をインナーレース４ｂに摺接させて両者間の電気的導通を図っても良く、或いはアウターレース４ａに形成した突起とインナーレース４ｂに形成した突起とを摺接させて両者間の電気的導通を図っても良く、図６に示すように金属製又は導電性樹脂製又は樹脂と金属とから成るクラッド材製の防塵用シール部材４ｆをアウターレース４ａとインナーレース４ｂとに摺接させて両者間の電気的導通を図っても良い。防塵用シール部材４ｆは自らの弾性力によりアウターレース４ａの内周面とインナーレース４ｂの外周面とに押し付けられるのが、良好な導通を確保する観点から望ましい。
【００１４】
転動体４ｃ、４ｄを絶縁材で形成し、或いは絶縁材で被覆し、電極部品１２、転動体保持器４ｅ、インナーレース４ｂの突起４ｂ′、アウターレース４ａの突起、アウターレース４ａの突起とインナーレース４ｂの突起、防塵用シール部材４ｆのみにより、アウターレース４ａとインナーレース４ｂとの電気的導通を図っても良い。転動体４ｃ、４ｄの電食を完全に防止することができ、転動体４ｃ、４ｄの電食による軸受４の寿命低下を完全に防止することができる。
転動体４ａ又は４ｂの一方を導電材で形成し、他方を絶縁材で形成し或いは絶縁材で被覆しても良い。絶縁材で形成され或いは絶縁体で被覆された転動体は通電されず電食しない。電食しない転動体が存在するので、特開平１０−２８１１８１号公報の電磁クラッチ用電極に比べて軸受の寿命低下が抑制される。
軸受４が形成する第２電極を電磁コイル２の正極に電気的に接続し、円環部材５、６、スリップリング７、９、電極部品１１が形成する第１電極を電磁コイル２の負極に電気的に接続しても良い。この場合は、軸受４のアウターレース４ａをローター１に対して絶縁すると共に電磁コイル２の正極側の巻線端部にリード線を介して接続し、軸受４のインナーレース４ｂを従動側機器に対して絶縁すると共に従動側機器から延びるリード線に接続する。他方円環部材５を電磁コイル２の負極側の巻線端部に電気的に導通させ、円環部材６を従動側機器を介してアースする。
【００１５】
【発明の効果】
以上説明したごとく、本発明に係る電磁クラッチ用電極においては、軸受が形成する第２電極は、電磁コイルの正極又は負極の何れか一方にのみ電気的に接続される。軸受は複数列の転動体を有しているので、当該複数列の転動体を介して電磁コイルに電流が流れ、或いは電磁コイルから電流が流れても、一列の転動体を流れる電流値は特開平１０−２８１１８１号公報の電磁クラッチ用電極に比べて少ない。この結果転動体の電食が抑制され、特開平１０−２８１１８１号公報の電磁クラッチ用電極に比べて軸受の寿命低下が抑制される。他方、円環板と円環板に摺接する電極部品とを備える第１電極は、電磁コイルの正極又は負極の何れか一方のみに電気的に接続されるので、当該電極の数は１で良い。この結果、円環板と円環板に摺接する電極部品とを備える従来の電磁クラッチ用電極を、軸方向に二つ並べて配設し、電磁コイルの正極と負極とに電気的に接続する場合に比べて比べて電磁クラッチの軸方向長さが短縮される。
【図面の簡単な説明】
【図１】本発明の実施例に係る電磁クラッチ用電極と、当該電極を備える電磁クラッチの一部を切り欠いた斜視図である。
【図２】本発明の実施例に係る電磁クラッチ用電極の部分斜視図である。
【図３】本発明の実施例に係る電磁クラッチ用電極の部分斜視図である。
【図４】本発明の他の実施例に係る電磁クラッチ用電極の断面図である。
【図５】本発明の他の実施例に係る電磁クラッチ用電極の断面図である。
【図６】本発明の他の実施例に係る電磁クラッチ用電極の断面図である。
【符号の説明】
１　ローター
２　電磁コイル
３　アーマチュア
４　軸受
４ａ　外側レース
４ｂ　内側レース
４ｃ、４ｄ　転動体
４ｅ　転動体保持器
４ｆ　防塵用シール部材
５、６　円環部材
７　内側スリップリング
９　外側スリップリング
１１、１２　電極部品[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electrode for an electromagnetic clutch.
[0002]
[Prior art]
A rotating member made of a magnetic material that is rotated and driven by a drive source, a bearing that rotatably supports the rotating member with respect to a housing of a driven device, and a rotating member that rotates integrally with the rotating member and energizes the rotating member to energize the rotating member. An electromagnetic coil for magnetizing, and an armature fixed to the driven device and disposed opposite to the rotating member, the armature being attracted to the magnetized rotating member. Electromagnetic clutch electrode, comprising an outer race of the bearing, an inner race of the bearing, and a row of rolling elements sandwiched between the outer race and the inner race, and electrically connected to a positive electrode of the electromagnetic coil. A first electrode, an outer race of the bearing, an inner race of the bearing, and a row of rolling elements sandwiched between the outer race and the inner race. And is insulated from the first electrode, second electrode and the electromagnetic clutch electrode comprising electrically connected to the negative pole of the electromagnetic coil is disclosed in JP-A-10-281181.
When the electromagnetic clutch electrode disclosed in Japanese Patent Application Laid-Open No. H10-281181 is used, two conventional electromagnetic clutch electrodes each having an annular plate and an electrode component that is in sliding contact with the annular plate are arranged side by side in the axial direction. The advantage that the axial length of the electromagnetic clutch is reduced as compared with the case where the positive and negative electrodes are electrically connected is obtained.
[0003]
[Problems to be solved by the invention]
In the electromagnetic clutch electrode disclosed in Japanese Patent Application Laid-Open No. H10-281181, current flows into the electromagnetic coil through a row of rolling elements, and current flows out of the electromagnetic coil through a row of rolling elements. There is a problem that erosion is severe and the life of the bearing is significantly reduced.
The present invention has been made in view of the above problems, and a reduction in the life of a bearing is suppressed as compared with the electrode for an electromagnetic clutch disclosed in Japanese Patent Application Laid-Open No. HEI 10-281181. A conventional electromagnetic clutch electrode having two electrodes arranged side by side in the axial direction, and the axial length of the electromagnetic clutch can be reduced as compared with the case where the electrodes are electrically connected to the positive electrode and the negative electrode of the electromagnetic coil. An object is to provide an electrode for a clutch.
[0004]
[Means for Solving the Problems]
In order to solve the above problems, in the present invention, a rotating member made of a magnetic material that is rotationally driven by a driving source, a bearing that rotatably supports the rotating member with respect to a housing of a driven device, An electromagnetic coil that rotates integrally with the member and magnetizes the rotating member by energization, and an armature that is fixed to the driven device and disposed to face the rotating member and is attracted to the magnetized rotating member. An electromagnetic clutch electrode for energizing the electromagnetic coil of the electromagnetic clutch comprising an annular plate and an electrode component that is in sliding contact with the annular plate, and electrically connected to one of the positive electrode and the negative electrode of the electromagnetic coil. A first electrode that is connected and does not form a bearing, an outer race of the bearing, an inner race of the bearing, and a plurality of rows of rolling elements sandwiched between the outer race and the inner race The provided, to provide an electrode for an electromagnetic clutch, characterized in that it comprises a second electrode electrically connected to the other of the electromagnetic coil positive or negative electrode.
In the electromagnetic clutch electrode according to the present invention, the second electrode formed by the bearing is electrically connected to only one of the positive electrode and the negative electrode of the electromagnetic coil. Since the bearing has a plurality of rows of rolling elements, even if a current flows through the electromagnetic coil via the plurality of rows of rolling elements, or a current flows from the electromagnetic coil, the current value flowing through the single row of rolling elements is particularly large. The number is smaller than the electromagnetic clutch electrode disclosed in Japanese Unexamined Patent Publication No. 10-281181. As a result, the electrolytic corrosion of the rolling elements is suppressed, and a decrease in the life of the bearing is suppressed as compared with the electromagnetic clutch electrode disclosed in Japanese Patent Application Laid-Open No. 10-281181. On the other hand, the first electrode including the annular plate and the electrode component that is in sliding contact with the annular plate is electrically connected to only one of the positive electrode and the negative electrode of the electromagnetic coil. . As a result, when two conventional electromagnetic clutch electrodes each including a circular plate and an electrode component that is in sliding contact with the circular plate are arranged side by side in the axial direction and electrically connected to the positive electrode and the negative electrode of the electromagnetic coil. The axial length of the electromagnetic clutch is reduced as compared with the case of (1).
[0005]
In a preferred aspect of the present invention, the outer race and the inner race are electrically connected to each other through a component of the bearing except for a rolling element sandwiched between the outer race and the inner race of the bearing.
If the outer race and the inner race are electrically connected to each other through the bearing components other than the rolling elements, the current flowing through the rolling elements is reduced, the electrolytic corrosion of the rolling elements is further suppressed, and the life of the bearing is reduced. It is further suppressed.
The constituent member may be an annular member fitted into a circumferential groove formed on the inner peripheral surface of the outer race and the outer peripheral surface of the inner race, or a retainer of a rolling element, and may be formed on the outer race and / or the inner race. It may be a projected protrusion or a dustproof seal member. It is desirable that the annular member be pressed against the circumferential grooves formed on the inner peripheral surface of the outer race and the outer peripheral surface of the inner race by its own elastic force from the viewpoint of ensuring good conduction. It is desirable that the dustproof seal member is pressed against the inner peripheral surface of the outer race and the outer peripheral surface of the inner race by its own elastic force from the viewpoint of ensuring good conduction.
[0006]
In a preferred embodiment of the present invention, the rolling elements are formed of or covered with an insulating material.
If the outer race and the inner race are electrically connected only with the bearing components excluding the rolling elements, electrolytic corrosion of the rolling elements can be completely prevented, and the life of the bearings will be shortened due to the electrolytic corrosion of the rolling elements. Can be completely prevented.
[0007]
In a preferred aspect of the present invention, any one of a plurality of rows of rolling elements sandwiched between an outer race and an inner race of the bearing is formed of a conductor, and the other row of rolling elements is formed of an insulating material. It is covered with insulating material.
A row of rolling elements formed of or covered with an insulator in a plurality of rows of rolling elements is not energized and does not undergo electrolytic corrosion. Since there are rolling elements that do not undergo electrolytic corrosion, a reduction in the life of the bearing is suppressed as compared with the electromagnetic clutch electrode disclosed in JP-A-10-281181.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
An electrode for an electromagnetic clutch according to an embodiment of the present invention will be described.
As shown in FIG. 1, an electromagnetic clutch incorporating electrodes according to the present embodiment includes a rotor 1 made of a magnetic material that is driven to rotate around an axis X by a drive source (not shown), and a rotor 1 fixed to the rotor 1. An electromagnetic coil 2 that rotates integrally and magnetizes the rotor 1 when energized, and is fixed to the rotating shaft of a driven-side device (not shown) rotatable around the axis X and disposed opposite to the rotor 1 and magnetized. Armature 3 adsorbed to rotor 1. The rotor 1 is supported by a housing (not shown) of the driven device via a bearing 4 so as to be rotatable around the axis X.
[0009]
A circumferential groove 5a is formed on the inner circumferential surface of the annular member 5 made of an insulating material fixed to the end face of the rotor 1.
A circumferential groove 6a is formed on the outer peripheral surface of the annular member 6 made of an insulating material fixed to the housing of the driven device, facing the circumferential groove 5a.
As shown in FIGS. 1 and 2, the inner slip ring 7 is fitted and fixed in the circumferential groove 6a. A peripheral groove 7 a is formed on the outer peripheral surface of the inner slip ring 7. The inner slip ring 7 is connected to a lead wire 8 extending from the driven device.
The outer slip ring 9 is fitted and fixed in the circumferential groove 5a. A peripheral groove 9 a is formed on the inner peripheral surface of the outer slip ring 9. The outer slip ring 9 is connected via a lead wire 10 to a winding end on the positive electrode side of the electromagnetic coil 2.
A retaining ring-shaped electrode component 11 is disposed between the inner slip ring 7 and the outer slip ring 9. The outer peripheral portion of the electrode component 11 is fitted into the peripheral groove 9a of the outer slip ring 9, and is in sliding contact with the bottom surface and the side surface of the peripheral groove 9a. The inner peripheral portions of both end portions 11a that are turned inward in the radial direction of the electrode component 11 are fitted into the peripheral grooves 7a of the inner slip ring 7, and are in sliding contact with the bottom and side surfaces of the peripheral grooves 7a.
A first electrode is formed by the ring members 5 and 6, the slip rings 7 and 9, and the electrode component 11.
[0010]
As shown in FIGS. 1 and 3, the bearing 4 is sandwiched between an outer race 4a fixed to the rotor 1, an inner race 4b fixed to the housing of the driven device, and the outer race 4a and the inner race 4b. It has two rows of rolling elements 4c and 4d. The outer race 4a is electrically connected to the end of the winding of the electromagnetic coil 2 on the negative electrode side. The inner race 4b is grounded via a driven device.
A circumferential groove 4a 'is formed on the inner circumferential surface of the outer race 4a, and a circumferential groove 4b' is formed on the outer circumferential surface of the inner race 4b. The outer peripheral portion of the retaining ring-shaped electrode component 12 is fitted in the peripheral groove 4a 'of the outer race, and is in sliding contact with the bottom and side surfaces of the peripheral groove 4a'. The inner peripheral portions of both end portions 12a turned radially inward of the electrode component 12 are fitted into the peripheral grooves 4b 'of the inner race, and are in sliding contact with the bottom and side surfaces of the peripheral grooves 4b'. The electrode component 12 is pressed against the circumferential grooves 4a 'and 4b' by its own elastic force.
The bearing 4 forms a second electrode.
[0011]
In the above-described electromagnetic clutch, when the rotor 1 is rotationally driven by an external drive source (not shown), the outer slip ring 9 rotates integrally with the rotor 1. When the electrode component 11 comes into sliding contact with the rotating outer slip ring 9 and the stopped inner slip ring 7, the outer slip ring 9 and the inner slip ring 7 are electrically connected. As a result, current flows from the driven device to the electromagnetic coil 2 via the first electrode.
The current flowing out of the electromagnetic coil 2 flows from the outer race 4a of the bearing 4 to the inner race 4b of the bearing 4 through the rolling elements 4c and 4d and the electrode component 12, and is grounded through the driven device.
[0012]
In the electrode for an electromagnetic clutch according to the present embodiment, the second electrode formed by the bearing 4 is electrically connected only to the negative electrode of the electromagnetic coil 2. Since the bearing has two rows of rolling elements 4c and 4d, even if current flows from the electromagnetic coil 2 to the driven device via the two rows of rolling elements 4c and 4d, each row of rolling elements 4c and 4d The value of the current flowing through 4d is smaller than that of the electromagnetic clutch electrode disclosed in JP-A-10-281181. As a result, the electrolytic corrosion of the rolling elements 4c and 4d is suppressed, and the reduction in the life of the bearing 4 is suppressed as compared with the electromagnetic clutch electrode disclosed in JP-A-10-281181. Since the current also flows from the electromagnetic coil 2 to the driven device through the electrode component 12, the value of the current flowing through the rolling elements 4c and 4d is further reduced, and the electrolytic corrosion of the rolling elements 4c and 4d is further suppressed. Is further reduced. On the other hand, the first electrode including the annular members 5 and 6 and the electrode component 11 slidably contacting the annular members 5 and 6 via the slip rings 9 and 7 is electrically connected to only the positive electrode of the electromagnetic coil 2. Therefore, the number of the electrodes may be one. As a result, two conventional electromagnetic clutch electrodes each including a circular plate and an electrode component that slides on the circular plate are arranged side by side in the X-axis direction, and are electrically connected to the positive electrode and the negative electrode of the electromagnetic coil 2. The axial length of the electromagnetic clutch is reduced as compared with the case.
Since the electrode component 12 is pressed against the peripheral grooves 4a 'and 4b' by its own elastic force, the sliding contact between the electrode component 12 and the peripheral grooves 4a 'and 4b' is stabilized, and the outer race through the electrode component 12 is provided. Electrical conduction between the inner race 4b and the inner race 4b is stabilized.
[0013]
As shown in FIG. 4, instead of the electrode parts 12, the projections 4e 'formed on the retainers 4e of the rolling elements 4c and 4d are brought into sliding contact with the outer race 4a and the inner race 4b to achieve electrical conduction between the two. As shown in FIG. 5, the protrusion 4b 'formed on the inner race 4b may be slid into contact with the outer race 4a to achieve electrical conduction between them, or the protrusion formed on the outer race 4a may be The electrical connection between the outer race 4a and the projection formed on the inner race 4b may be brought into sliding contact with the race 4b to achieve electrical conduction between them. As shown in FIG. 6, a dust-proof sealing member 4f made of metal, conductive resin, or a clad material made of resin and metal is brought into sliding contact with the outer race 4a and the inner race 4b. It may attempt to electrical conduction therebetween. It is desirable that the dustproof seal member 4f be pressed against the inner peripheral surface of the outer race 4a and the outer peripheral surface of the inner race 4b by its own elastic force from the viewpoint of ensuring good conduction.
[0014]
The rolling elements 4c and 4d are formed of or covered with an insulating material, and the electrode component 12, the rolling element retainer 4e, the projection 4b 'of the inner race 4b, the projection of the outer race 4a, the projection of the outer race 4a and the inner Electrical continuity between the outer race 4a and the inner race 4b may be achieved only by the protrusion of the race 4b and the dustproof seal member 4f. The electrolytic corrosion of the rolling elements 4c and 4d can be completely prevented, and the shortening of the life of the bearing 4 due to the electrolytic corrosion of the rolling elements 4c and 4d can be completely prevented.
One of the rolling elements 4a or 4b may be formed of a conductive material, and the other may be formed of an insulating material or covered with an insulating material. Rolling elements formed of an insulating material or coated with an insulating material are not energized and do not undergo electrolytic corrosion. Since there are rolling elements that do not undergo electrolytic corrosion, a reduction in the life of the bearing is suppressed as compared with the electromagnetic clutch electrode disclosed in JP-A-10-281181.
The second electrode formed by the bearing 4 is electrically connected to the positive electrode of the electromagnetic coil 2, and the first electrode formed by the annular members 5 and 6, the slip rings 7 and 9, and the electrode component 11 is used as the negative electrode of the electromagnetic coil 2. You may electrically connect. In this case, the outer race 4a of the bearing 4 is insulated from the rotor 1 and connected to the positive winding end of the electromagnetic coil 2 via a lead wire, and the inner race 4b of the bearing 4 is connected to the driven device. It is insulated and connected to the lead wire extending from the driven device. On the other hand, the annular member 5 is electrically connected to the winding end of the electromagnetic coil 2 on the negative electrode side, and the annular member 6 is grounded via the driven device.
[0015]
【The invention's effect】
As described above, in the electrode for an electromagnetic clutch according to the present invention, the second electrode formed by the bearing is electrically connected to only one of the positive electrode and the negative electrode of the electromagnetic coil. Since the bearing has a plurality of rows of rolling elements, even if a current flows through the electromagnetic coil via the plurality of rows of rolling elements, or even if a current flows from the electromagnetic coil, the current value flowing through the single row of rolling elements is particularly large. The number is smaller than the electromagnetic clutch electrode disclosed in Japanese Unexamined Patent Publication No. 10-281181. As a result, the electrolytic corrosion of the rolling elements is suppressed, and a decrease in the life of the bearing is suppressed as compared with the electromagnetic clutch electrode disclosed in Japanese Patent Application Laid-Open No. 10-281181. On the other hand, since the first electrode including the annular plate and the electrode component that is in sliding contact with the annular plate is electrically connected to only one of the positive electrode and the negative electrode of the electromagnetic coil, the number of the electrodes may be one. . As a result, two conventional electromagnetic clutch electrodes each having an annular plate and an electrode component that slides on the annular plate are arranged side by side in the axial direction, and are electrically connected to the positive electrode and the negative electrode of the electromagnetic coil. The axial length of the electromagnetic clutch is reduced as compared with the case of (1).
[Brief description of the drawings]
FIG. 1 is a perspective view of an electrode for an electromagnetic clutch according to an embodiment of the present invention, and a part of an electromagnetic clutch provided with the electrode, which is cut away.
FIG. 2 is a partial perspective view of an electrode for an electromagnetic clutch according to the embodiment of the present invention.
FIG. 3 is a partial perspective view of an electromagnetic clutch electrode according to the embodiment of the present invention.
FIG. 4 is a sectional view of an electrode for an electromagnetic clutch according to another embodiment of the present invention.
FIG. 5 is a sectional view of an electrode for an electromagnetic clutch according to another embodiment of the present invention.
FIG. 6 is a sectional view of an electrode for an electromagnetic clutch according to another embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Rotor 2 Electromagnetic coil 3 Armature 4 Bearing 4a Outer race 4b Inner race 4c, 4d Rolling element 4e Rolling element retainer 4f Dustproof seal member 5, 6 Ring member 7 Inner slip ring 9 Outer slip ring 11, 12 Electrode parts

Claims

A rotating member made of a magnetic material that is rotated and driven by a drive source, a bearing that rotatably supports the rotating member with respect to the housing of the driven device, and a rotating member that rotates integrally with the rotating member and energizes the rotating member. An electromagnetic coil for magnetizing, and an armature fixed to the driven device and disposed opposite to the rotating member and energized by the magnetized rotating member for energizing the electromagnetic coil of the electromagnetic clutch. An electrode for an electromagnetic clutch, comprising a toroidal plate and an electrode component slidably in contact with the toroidal plate, a first electrode electrically connected to one of a positive electrode and a negative electrode of the electromagnetic coil and not forming a bearing; An outer race of the bearing, an inner race of the bearing, and a plurality of rows of rolling elements sandwiched between the outer race and the inner race; Electrode electromagnetic clutch, characterized in that it comprises a second electrode electrically connected to the.

The electromagnetic system according to claim 1, wherein the outer race and the inner race are electrically connected to each other through a component of the bearing except for a rolling element sandwiched between the outer race and the inner race of the bearing. Electrode for clutch.

The constituent member is an annular member fitted into a circumferential groove formed on the inner peripheral surface of the outer race and the outer peripheral surface of the inner race, and the annular member is formed by the elastic force of the annular member. The electrode for an electromagnetic clutch according to claim 2, wherein the electrode is pressed against the circumferential groove.

The electrode for an electromagnetic clutch according to claim 2, wherein the constituent member is a retainer for a rolling element.

The electrode according to claim 2, wherein the constituent member is a protrusion formed on an outer race and / or an inner race.

The electrode according to claim 2, wherein the constituent member is a dustproof seal member.

The electrode for an electromagnetic clutch according to any one of claims 2 to 6, wherein the rolling element is formed of an insulating material or is coated with the insulating material.

Any one of a plurality of rows of rolling elements sandwiched between an outer race and an inner race of the bearing is formed of a conductor, and the other row of rolling elements is formed of an insulating material or covered with an insulating material. The electrode for an electromagnetic clutch according to any one of claims 1 to 6, wherein: