JP2009079643A

JP2009079643A - Current-carrying rolling bearing

Info

Publication number: JP2009079643A
Application number: JP2007248452A
Authority: JP
Inventors: Yasunobu Fujita; 安伸藤田; Kosho Otani; 晃章大谷; Keisuke Kimura; 啓亮木村
Original assignee: NSK Ltd
Current assignee: NSK Ltd
Priority date: 2007-09-26
Filing date: 2007-09-26
Publication date: 2009-04-16

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure that can prevent the damage of rolling surfaces of respective rolling bodies, and inner and outer ring raceways forming a rolling bearing, caused by electric erosion, when a current flows from the outside to the rolling bearing. <P>SOLUTION: A flexible and conductive electrical conductive material 28 is buried and held in an elastic material 12 of a sealing ring 10a, and the radial outer end of each electrical conductive material 28 is exposed from the radially outer end edge of a projected portion 13 of the elastic material 12, and made to be conductive with a lock groove 9 of the outer ring 3. In addition, the radial inner end of the electrical conductive material 28 is exposed from the radially inner end edge of the seal lip 14, and made to be conductive with a seal groove 15 of the inner ring 5. Thereby, the outer ring 3 and the inner ring 5 are made elecviatly conductive with each other so that the problem is solved. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

この発明は、一般産業用汎用モータや発電機用ジェネレータ（風力発電機等）、鉄道車両用主電動機等の様に、回転軸に電流が流れる可能性がある回転支持部に組み込む電食防止用の通電式転がり軸受の改良に関する。 The present invention is for electric corrosion prevention incorporated in a rotation support portion in which a current may flow through a rotating shaft such as a general-purpose motor for general industrial use, a generator for a generator (wind generator, etc.), a main motor for a railway vehicle, etc. The present invention relates to the improvement of the energizing type rolling bearing.

各種回転機械装置の軸受部等、各種回転部分を支持する為の転がり軸受として、例えば図６に示す様な玉軸受１が広く使用されている。この玉軸受１は、内周面に外輪軌道２を有する外輪３と、外周面に内輪軌道４を有する内輪５とを同心に配置し、これら外輪軌道２と内輪軌道４との間に複数個の玉６を転動自在に設けて成る。図示の例の場合、上記外輪軌道２と内輪軌道４とは、共に深溝型としている。又、上記複数個の玉６は、保持器７に設けたポケット８内に、転動自在に保持している。又、上記外輪３の両端部内周面にそれぞれ全周に亙って形成した係止溝９には、それぞれシールリング１０の外周縁部（後述する突出部１３）を係止している。 For example, a ball bearing 1 as shown in FIG. 6 is widely used as a rolling bearing for supporting various rotating parts such as bearings of various rotating machine devices. In the ball bearing 1, an outer ring 3 having an outer ring raceway 2 on an inner peripheral surface and an inner ring 5 having an inner ring raceway 4 on an outer peripheral surface are arranged concentrically, and a plurality of the ball bearings 1 are provided between the outer ring raceway 2 and the inner ring raceway 4. The ball 6 is provided so as to be able to roll freely. In the case of the illustrated example, both the outer ring raceway 2 and the inner ring raceway 4 are deep groove types. Further, the plurality of balls 6 are held in a pocket 8 provided in the cage 7 so as to freely roll. Further, outer peripheral edge portions (protruding portions 13 to be described later) of the seal ring 10 are locked in locking grooves 9 formed on the inner peripheral surfaces of both ends of the outer ring 3 over the entire circumference.

これら各シールリング１０は、それぞれ鋼板等の金属板を円輪状に形成して成る芯金１１で、ゴムの如きエラストマー等の弾性材１２を補強する事により、全体を円輪状に形成して成る。そして、この弾性材１２の外周縁部で、上記芯金１１の外周縁よりも少しだけ径方向（図６の上下方向）外方に突出した突出部１３を、上記係止溝９に係止している。一方、上記弾性材１２の内周縁部は、上記芯金１１の内周縁よりも径方向内方に十分に突出させて、この突出させた部分によりシールリップ１４を構成している。更に、このシールリップ１４の端縁部を、上記内輪５の両端部外周面に形成したシール溝１５の側壁面に摺接させている。 Each of these seal rings 10 is a core metal 11 formed by forming a metal plate such as a steel plate in an annular shape, and is formed in an annular shape as a whole by reinforcing an elastic material 12 such as an elastomer such as rubber. . Then, at the outer peripheral edge portion of the elastic member 12, the protruding portion 13 protruding slightly outward in the radial direction (vertical direction in FIG. 6) from the outer peripheral edge of the core metal 11 is locked in the locking groove 9. is doing. On the other hand, the inner peripheral edge portion of the elastic member 12 is sufficiently protruded radially inward from the inner peripheral edge of the core metal 11, and the protruding portion constitutes a seal lip 14. Further, the edge portion of the seal lip 14 is brought into sliding contact with the side wall surface of the seal groove 15 formed on the outer peripheral surface of both end portions of the inner ring 5.

上述の様に構成され作用する玉軸受１を、例えばインバータモータやサーボモータ等の一般産業用汎用モータの様に、回転軸に電流が流れる可能性がある回転支持部に組み込む場合、この回転軸を流れる電流が、上記玉軸受１を構成する上記各玉６に流れると、これら各玉６の転動面、並びに上記内外輪５、３の軌道面が電気的に腐食（電食）する。この為、上記玉軸受１からこの電食に基づく異音が発生したり、この玉軸受１の耐久性が損なわれてしまう事が考えられる。 When the ball bearing 1 configured and operated as described above is incorporated in a rotation support portion in which a current may flow through the rotation shaft, such as a general-purpose industrial motor such as an inverter motor or a servo motor, the rotation shaft When the current flowing through the ball bearings 1 constitutes the balls 6 constituting the ball bearing 1, the rolling surfaces of the balls 6 and the raceways of the inner and outer rings 5, 3 are electrically corroded (electric corrosion). For this reason, it is conceivable that an abnormal noise based on the electric corrosion is generated from the ball bearing 1 or the durability of the ball bearing 1 is impaired.

この様な上記玉軸受１に流れる電流に基づく上記電食を防止する技術として従来から、特許文献１〜３に記載された構造が知られている。これら特許文献１〜３に記載された転がり軸受の特徴は、この転がり軸受に電食を防止する構造を設けた点にある。この点以外の構造は、上記図６に示した玉軸受１とほぼ同様である。この為、これら特許文献１〜３に記載された構造の特徴の説明を、上記図６の符号を用いて行なう。
上記特許文献１〜３のうちの、特許文献１に記載された従来技術は、上記図６に示している前記各シールリング１０の弾性材１２を、ゴム材にカーボンブラック等の導電性添加剤を混練した導電性ゴムにより構成している。この様にして、上記外輪３と上記内輪５とを電気的に導通している。
又、上記特許文献２に記載された従来技術の場合、上記外輪３と上記内輪５との間に円環状の通電ワイヤを設け、この通電ワイヤを弾性変形させる事で、これら外輪３、内輪５の両方に接触させている。この様にして、上記外輪３と上記内輪５とを電気的に導通している。
又、上記特許文献３に記載された従来技術の場合、上記玉軸受１の内部に、基油にカーボンブラック等の導電性添加剤を添加した導電性グリースを封入する事で、上記外輪３と上記内輪５とを電気的に導通している。 Conventionally, structures described in Patent Documents 1 to 3 are known as techniques for preventing the electrolytic corrosion based on the current flowing in the ball bearing 1. The feature of the rolling bearings described in these patent documents 1 to 3 is that the rolling bearing is provided with a structure for preventing electrolytic corrosion. The structure other than this point is almost the same as the ball bearing 1 shown in FIG. For this reason, the features of the structures described in Patent Documents 1 to 3 will be described using the reference numerals in FIG.
Among the above-mentioned Patent Documents 1 to 3, the prior art described in Patent Document 1 is that the elastic material 12 of each of the seal rings 10 shown in FIG. The conductive rubber is kneaded. In this way, the outer ring 3 and the inner ring 5 are electrically connected.
In the case of the prior art described in Patent Document 2, an annular energizing wire is provided between the outer ring 3 and the inner ring 5, and the energizing wire is elastically deformed, whereby the outer ring 3 and the inner ring 5. In contact with both. In this way, the outer ring 3 and the inner ring 5 are electrically connected.
Further, in the case of the prior art described in Patent Document 3, the outer ring 3 and the ball bearing 1 are sealed by encapsulating conductive grease in which a conductive additive such as carbon black is added to the base oil. The inner ring 5 is electrically connected.

上述の様な特許文献１〜３に記載された従来技術のうち、特許文献１に記載された従来技術の場合、ゴム材自体の体積固有抵抗率が高い為、十分な導電性を確保するには、カーボンブラック等の導電性添加剤の混入率を大きくする必要がある。しかし、この混入率を大きくした場合、上記導電性ゴムの弾性や耐久性が不足してしまう事が考えられる。
又、上記特許文献２に記載された従来技術の場合、上記通電ワイヤにより上記外輪３と上記内輪５との電気的な導電性を確保する事はできる。しかし、この通電ワイヤは、弾性変形した状態で、上記外輪３、及び上記内輪５と接触している。この為、この弾性変形の量によっては、動トルク、摩擦損失、発熱が増大してしまう事が考えられる。又、上記通電ワイヤを別体で設けている為、部品点数が多くなり、部品製作コスト、部品管理コスト、組立作業コストが嵩む事が考えられる。
更に、上記特許文献３に記載された従来技術の場合、回転初期に於ける導電性は優れているが、時間の経過と共に、上記導電性グリースが劣化したり、前記各玉６、６の転動面と前記外輪軌道２、及び上記内輪軌道４との接触部に酸化被膜が生じたり、基油とカーボンブラックとが分離する等して、上記導電性が低下する事が考えられる。 Among the conventional techniques described in Patent Documents 1 to 3 as described above, in the case of the conventional technique described in Patent Document 1, the volume resistivity of the rubber material itself is high, so that sufficient conductivity is ensured. Needs to increase the mixing ratio of conductive additives such as carbon black. However, when the mixing rate is increased, the elasticity and durability of the conductive rubber may be insufficient.
In the case of the prior art described in Patent Document 2, electrical conductivity between the outer ring 3 and the inner ring 5 can be ensured by the conducting wire. However, this energizing wire is in contact with the outer ring 3 and the inner ring 5 in an elastically deformed state. For this reason, depending on the amount of this elastic deformation, dynamic torque, friction loss, and heat generation may increase. Moreover, since the above-mentioned conducting wire is provided separately, the number of parts increases, and it is considered that the part production cost, the part management cost, and the assembly work cost increase.
Furthermore, in the case of the prior art described in Patent Document 3, the conductivity at the initial stage of rotation is excellent. However, as time elapses, the conductive grease deteriorates or the balls 6 and 6 roll. It is conceivable that the conductivity decreases due to the formation of an oxide film at the contact portion between the moving surface and the outer ring raceway 2 and the inner ring raceway 4 or the separation of the base oil and carbon black.

実開昭５９−７１３６１号公報Japanese Utility Model Publication No.59-71361 特許第３６５４９２１号公報Japanese Patent No. 3654921 特開昭４７−２１４０２号公報JP 47-21402 A

本発明は、上述の様な事情に鑑みて、転がり軸受に外部から電流が流れた場合に、この転がり軸受を構成する各転動体の転動面や、上記内輪軌道及び外輪軌道に電食による損傷が発生する事を、長期に亙り防止できる構造を低コストに実現すべく発明したものである。 In view of the circumstances as described above, the present invention is based on the electrolytic corrosion of the rolling surfaces of the rolling elements constituting the rolling bearing, the inner ring raceway, and the outer ring raceway when current flows from the outside to the rolling bearing. The invention was invented to realize a structure capable of preventing the occurrence of damage over a long period of time at a low cost.

本発明の対象となる保持器付き転がり軸受は、外輪と、内輪と、複数個の転動体と、シールリングとを備える。
このうちの、外輪は、内周面に外輪軌道を有する。
又、上記内輪は、外周面に内輪軌道を有する。
又、上記各転動体は、上記外輪軌道と上記内輪軌道との間に転動自在に設けられている。
又、上記シールリングは、全体を円輪状としている。又、このシールリングの内外両周縁のうちの一方の周縁を、上記内輪の端部と上記外輪の端部とのうちの一方の端部に全周に亙って係止している。又、上記内外両周縁のうちの他方の周縁を、上記内輪の端部と上記外輪の端部とのうちの他方の端部の表面に全周に亙って摺接させている。この様にして、上記シールリングは、上記外輪の内周面と上記内輪の外周面との間に存在して上記各転動体を設置した軸受内部空間の端部開口を塞いでいる。更に、上記シールリングを介して、上記外輪と上記内輪とを電気的に導通させている。 A rolling bearing with a retainer that is an object of the present invention includes an outer ring, an inner ring, a plurality of rolling elements, and a seal ring.
Of these, the outer ring has an outer ring raceway on the inner peripheral surface.
The inner ring has an inner ring raceway on the outer peripheral surface.
Each of the rolling elements is provided between the outer ring raceway and the inner ring raceway so as to freely roll.
Further, the seal ring as a whole has a ring shape. Further, one of the inner and outer peripheral edges of the seal ring is engaged with one end of the inner ring and the outer ring over the entire circumference. The other of the inner and outer peripheral edges is in sliding contact with the surface of the other end of the inner ring and the outer ring over the entire circumference. In this way, the seal ring is present between the inner peripheral surface of the outer ring and the outer peripheral surface of the inner ring, and closes the end opening of the bearing internal space where the rolling elements are installed. Further, the outer ring and the inner ring are electrically connected through the seal ring.

特に、本発明の通電式転がり軸受に於いては、上記シールリングを構成する弾性材中に、可撓性及び導電性を有する導電材を包埋保持し、この導電材の両端を上記外輪と上記内輪とに、それぞれ電気的に導通させている。
上述の様な本発明を実施する場合に、例えば請求項２に記載した様に、上記導電材の両端を弾性材の外周縁部と内周縁部とにそれぞれ露出させて、この導電材の両端部を上記外輪及び内輪に、直接導通させる。
又、この様な請求項２に記載した発明を実施する場合に、例えば請求項３に記載した様に、上記弾性材の内外両周縁のうちの他方の周縁に形成したシールリップの先端に全周に亙り凹溝を形成して、この凹溝の両側部分を、それぞれ上記他方の表面に全周に亙って摺接させる。更に、上記導電材の端部をこの凹溝の両端部分にそれぞれ露出させる。
この様にして、この導電材の両端部を上記外輪及び内輪に、直接導通させる。
又、この様な請求項３に記載した発明を実施する場合に好ましくは、請求項４に記載した様に、上記凹溝と上記他方の表面とに囲まれる空間内に導電性を有する潤滑剤を封入する。 In particular, in the energizing type rolling bearing of the present invention, a conductive material having flexibility and conductivity is embedded and held in the elastic material constituting the seal ring, and both ends of the conductive material are connected to the outer ring. The inner ring is electrically connected to each other.
When carrying out the present invention as described above, for example, as described in claim 2, both ends of the conductive material are exposed to the outer peripheral edge portion and the inner peripheral edge portion of the elastic material, respectively. The part is directly connected to the outer ring and the inner ring.
Further, when the invention described in claim 2 is carried out, as described in claim 3, for example, the entire end of the seal lip formed on the other peripheral edge of the inner and outer peripheral edges of the elastic material is disposed. A groove is formed around the circumference, and both side portions of the groove are brought into sliding contact with the other surface over the entire circumference. Further, the end portions of the conductive material are exposed at both end portions of the groove.
In this way, both ends of the conductive material are directly conducted to the outer ring and the inner ring.
Further, when carrying out the invention described in claim 3, preferably, as described in claim 4, a lubricant having conductivity in a space surrounded by the groove and the other surface. Enclose.

又、上記請求項２〜４の構造とは別に、上述の様な本発明を実施する場合に、例えば請求項５に記載した様に、上記弾性材の他方の周縁に形成されたシールリップの先端に全周に亙って凹溝を形成する。そして、この凹溝の両端部分を、それぞれ上記他方の面に全周に亙り摺接させて、この凹溝と上記他方の面とに囲まれる空間内に導電性を有する潤滑剤を封入する。更に、上記導電材の一端部をこの凹溝の内面の一部に露出させる。この様にして、この導電材の一端部を上記潤滑剤を介して上記他方の面と導通させる。
又、上記請求項１〜５の構造を実施する場合に、具体的には、請求項６に記載した様に、上記導電材の形状を線状とする。
或いは、請求項７に記載した様に、上記導電材の形状をシート状とする。
或いは、請求項８に記載した様に、上記導電材の形状をメッシュ状とする。 In addition to the structure of the second to fourth aspects, when the present invention as described above is carried out, for example, as described in the fifth aspect, a seal lip formed on the other peripheral edge of the elastic material is used. A concave groove is formed at the tip over the entire circumference. Then, both end portions of the groove are brought into sliding contact with the other surface over the entire circumference, and a conductive lubricant is sealed in a space surrounded by the groove and the other surface. Furthermore, one end of the conductive material is exposed at a part of the inner surface of the groove. In this way, one end of the conductive material is electrically connected to the other surface via the lubricant.
Moreover, when implementing the structure of the said Claims 1-5, specifically, as described in Claim 6, the shape of the said electrically-conductive material is made into a linear form.
Alternatively, as described in claim 7, the shape of the conductive material is a sheet.
Alternatively, as described in claim 8, the shape of the conductive material is a mesh.

上述の様に構成する本発明の通電式転がり軸受は、シールリングを構成する弾性材中に、可撓性及び導電性を有する導電材を包埋保持して、この導電材の両端を上記外輪と上記内輪とに、それぞれ電気的に導通する導通機構を設ける事で、この導通機構の電気抵抗を低く保つ事ができる。これにより、外部から上記転がり軸受に電流が流れた場合に、この電流のうちの大部分は上記導通機構を流れる。この為、電食による損傷を防ぎたい部分（例えば、上記転がり軸受を構成する各玉の転動面や、上記内輪軌道及び外輪軌道）に大きな電流が流れる事を防止して、電食による損傷が発生する事を防止できる。
又、上記導電材は、上記シールリングを構成する弾性材中に包埋保持して一体に形成している。この為、部品点数を少なく抑える事ができ、部品管理コスト、組立作業コストが嵩む事を抑える事ができる。
尚、上記導電材は、上記シールリングを構成する弾性材を芯金にモールド成形する際に、キャビティー内の所定位置に設置する事により、容易にこの弾性材中に埋め込む事ができる為、大量生産に適している。 In the energizing type rolling bearing of the present invention configured as described above, a conductive material having flexibility and conductivity is embedded and held in an elastic material constituting a seal ring, and both ends of the conductive material are connected to the outer ring. By providing the inner ring and the inner ring with a conduction mechanism that conducts electricity, the electrical resistance of the conduction mechanism can be kept low. Thus, when a current flows from the outside to the rolling bearing, most of the current flows through the conduction mechanism. For this reason, it is possible to prevent large currents from flowing on the parts (for example, the rolling surfaces of the balls constituting the rolling bearing, the inner ring raceway and the outer ring raceway) which are desired to prevent damage due to electrolytic corrosion. Can be prevented from occurring.
Further, the conductive material is integrally formed by being embedded and held in an elastic material constituting the seal ring. For this reason, the number of parts can be reduced, and the increase in parts management cost and assembly work cost can be suppressed.
The conductive material can be easily embedded in the elastic material by installing it at a predetermined position in the cavity when the elastic material constituting the seal ring is molded into the core metal. Suitable for mass production.

［実施の形態の第１例］
図１〜２は、請求項１〜２、６〜８に対応する、本発明の実施の形態の第１例を示している。尚、本例の通電式玉軸受１ａの特徴は、この玉軸受１ａを構成するシールリング１０ａの構造を工夫して、外輪３と内輪５とを電気的に導通させる為の導通機構１９を設けた点にある。この特徴部分以外の構造及び作用は、前述の図６に示した玉軸受１を含め、従来から知られている玉軸受の場合とほぼ同様である。この為、重複する説明を省略若しくは簡略にし、以下、本例の特徴部分を中心に説明する。 [First example of embodiment]
FIGS. 1-2 has shown the 1st example of embodiment of this invention corresponding to Claims 1-2 and 6-8. The current-carrying ball bearing 1a according to the present embodiment is characterized by providing a conduction mechanism 19 for electrically connecting the outer ring 3 and the inner ring 5 by devising the structure of the seal ring 10a constituting the ball bearing 1a. It is in the point. The structure and operation other than this characteristic portion are almost the same as those of conventionally known ball bearings including the ball bearing 1 shown in FIG. For this reason, the overlapping description will be omitted or simplified, and the following description will focus on the features of this example.

図１は、本発明の対象である、通電式玉軸受１ａを示している。この玉軸受１ａを構成するシールリング１０ａは、上記図６に示した玉軸受１と同様に、それぞれ鋼板等の金属板を円輪状に形成して成る芯金１１で、ゴムの如きエラストマー等の弾性材１２を補強する事により、全体を円輪状に形成して成る。この弾性材１２の外周縁部であり、上記芯金１１の外周縁よりも少しだけ径方向（図１の上下方向）外方に突出た突出部１３を、上記外輪３の両端部内周面にそれぞれ全周に亙って形成した係止溝９に係止している。一方、上記弾性材１２の内周縁部は、上記芯金１１の内周縁よりも径方向内方に十分に突出させて、この突出させた部分によりシールリップ１４を構成している。そして、このシールリップ１４の端縁部を、上記内輪５の両端部外周面に形成したシール溝１５の側壁面に摺接させている。又、この様なシールリング１０ａには、上記外輪３と上記内輪５とを電気的に導通する為の導通機構１９を設けている。 FIG. 1 shows a current-carrying ball bearing 1a which is an object of the present invention. As with the ball bearing 1 shown in FIG. 6, the seal ring 10a constituting the ball bearing 1a is a metal core 11 formed by forming a metal plate such as a steel plate into an annular shape, and is made of an elastomer such as rubber. By reinforcing the elastic material 12, the whole is formed in an annular shape. Protruding portions 13 which are outer peripheral portions of the elastic member 12 and protrude slightly outward in the radial direction (vertical direction in FIG. 1) from the outer peripheral edge of the core metal 11 are formed on the inner peripheral surfaces of both ends of the outer ring 3. Each is locked in a locking groove 9 formed over the entire circumference. On the other hand, the inner peripheral edge portion of the elastic member 12 is sufficiently protruded radially inward from the inner peripheral edge of the core metal 11, and the protruding portion constitutes a seal lip 14. And the edge part of this seal lip 14 is made to slidably contact with the side wall surface of the seal groove 15 formed in the outer peripheral surface of the both ends of the said inner ring | wheel 5. As shown in FIG. Further, such a seal ring 10 a is provided with a conduction mechanism 19 for electrically conducting the outer ring 3 and the inner ring 5.

この導通機構１９は、上記シールリング１０ａを構成する弾性材１２中に、可撓性及び導電性を有する導電材１８を包埋保持する事で構成している。そして、これら各導電材１８の径方向外端部を上記突出部１３の径方向外端縁から露出させて上記外輪３の係止溝９の内面に、直接導通（接触）させている。又、上記導電材１８の径方向内端部を上記シールリップ１４の径方向内端縁から露出させる事で、上記内輪５のシール溝１５に、直接導通させている。この様にして、上記外輪３と上記内輪５とを電気的に導通させている。
尚、上記導電材１８と、上記内輪５のシール溝１５との接触部には、基油に導電性添加剤を添加した導電性グリース等の導電性潤滑剤を塗布しておく事が好ましい。 The conduction mechanism 19 is configured by embedding and holding a conductive material 18 having flexibility and conductivity in the elastic material 12 constituting the seal ring 10a. And the radial direction outer end part of each of these conductive materials 18 is exposed from the radial direction outer end edge of the said protrusion part 13, and is made to conduct | electrically_connect (contact) directly with the inner surface of the locking groove 9 of the said outer ring | wheel 3. Further, by exposing the radially inner end portion of the conductive material 18 from the radially inner end edge of the seal lip 14, the conductive material 18 is directly conducted to the seal groove 15 of the inner ring 5. In this way, the outer ring 3 and the inner ring 5 are electrically connected.
In addition, it is preferable to apply a conductive lubricant such as a conductive grease obtained by adding a conductive additive to the base oil to a contact portion between the conductive material 18 and the seal groove 15 of the inner ring 5.

又、上記各導電材１８の形状は、例えば、特許請求の範囲の請求項６に記載している様な線状、同じく請求項７に記載している様なシート状、同じく請求項８に記載している様なメッシュ状の物を採用できる。
又、上記各導電材１８の材質は、自己摺動性に優れ、摩耗しにくく、電気を通し易い事が必要である。例えば、銅や銅系合金、銀、金等の金属材料や、カーボンファイバ等の導電性繊維や、金属微粒子をコーティングした繊維等を用いる事ができる。
尚、上記弾性材１２中に包埋保持する上記各導電材１８の数は、特に限定しない。必要となる導通量及び弾性材１２の強度等を考慮して設計的に決定する。
又、上記各導電材１８の寸法も、特に限定しない。導通時の電流により破断しない程度の強度を備えられる様に、やはり弾性材１２の強度等を考慮しつつ、設計的に定める。
但し、上記各導電材１８の配置に関しては、図２の（Ａ）に模式的に示す様に、上記弾性材１２中に円周方向に関して、上記各導電材１８、１８を等配｛図２の（Ａ）の場合、円周方向に関して９０度間隔｝する事が好ましい。又、図２の（Ｂ）に模式的に示す様に、円周方向に関して等配した上記各導電材１８、１８同士を、径方向中間部で円輪状導電材２０等により電気的に導通する構造にすれば、これら各導電材１８の一部が破断してしまった場合でも、良好な導通性を長期に亙り確保できる。 The shape of each conductive material 18 is, for example, a linear shape as described in claim 6 of the claims, a sheet shape as described in claim 7, and also according to claim 8. A mesh-like object as described can be used.
The material of each conductive material 18 should be excellent in self-sliding property, less likely to wear, and easy to conduct electricity. For example, metal materials such as copper, copper-based alloys, silver, and gold, conductive fibers such as carbon fibers, fibers coated with metal fine particles, and the like can be used.
The number of each conductive material 18 embedded and held in the elastic material 12 is not particularly limited. The design is determined in consideration of the required amount of conduction and the strength of the elastic member 12.
Further, the dimensions of the conductive materials 18 are not particularly limited. It is determined in terms of design so that the strength of the elastic material 12 is taken into consideration so that it can be provided with a strength that does not break due to the current during conduction.
However, with respect to the arrangement of the conductive materials 18, as shown schematically in FIG. 2A, the conductive materials 18 and 18 are equally distributed in the elastic material 12 in the circumferential direction {FIG. In the case of (A), it is preferable that the interval is 90 degrees with respect to the circumferential direction. Further, as schematically shown in FIG. 2B, the conductive materials 18 and 18 arranged equally in the circumferential direction are electrically connected to each other by an annular conductive material 20 or the like in the middle portion in the radial direction. With the structure, even when a part of each of the conductive materials 18 is broken, good conductivity can be secured over a long period of time.

上述の様な本例の通電式玉軸受１ａによれば、上記シールリング１０ａを構成する弾性材１２中に、上記各導電材１８を包埋保持して、これら各導電材１８の両端を上記外輪３と上記内輪５との間に電気的に導通する導通機構１９を設けているので、この導通機構１９部分の電気抵抗を低く保つ事ができる。これにより、外部から上記玉軸受１ａに電流が流れた場合に、この電流のうちの大部分は、上記外輪３から上記導通機構１９を通って上記内輪５へと流れる。この為、電食による損傷を防ぎたい部分（例えば、上記玉軸受１ａを構成する各玉６の転動面２１や、外輪軌道２及び内輪軌道４）に大きな電流が流れる事を防止して、これらの部分に電食による損傷が発生する事を防止できる。
又、上記各導電材１８は、上記シールリング１０ａを構成する弾性材１２中に包埋保持して一体に形成している。この為、部品点数を少なく抑える事ができ、部品管理コスト、組立作業コストが嵩む事を抑える事ができる。
又、上記導電材１８と上記内輪５のシール溝１５との摺接部に、前記導電性潤滑剤を塗布すれば、上記摺接部の摺動性を向上し、摺動抵抗を低減できる。 According to the current-carrying ball bearing 1a of the present example as described above, the conductive materials 18 are embedded and held in the elastic material 12 constituting the seal ring 10a, and both ends of the conductive materials 18 are held at the ends. Since the conduction mechanism 19 is provided between the outer ring 3 and the inner ring 5, the electrical resistance of the conduction mechanism 19 can be kept low. Thereby, when a current flows from the outside to the ball bearing 1 a, most of the current flows from the outer ring 3 through the conduction mechanism 19 to the inner ring 5. For this reason, it is possible to prevent a large current from flowing through a portion (for example, the rolling surface 21 of each ball 6 constituting the ball bearing 1a, the outer ring raceway 2 and the inner ring raceway 4) to prevent damage due to electric corrosion. It is possible to prevent these parts from being damaged by electric corrosion.
The conductive materials 18 are integrally formed by being embedded and held in the elastic material 12 constituting the seal ring 10a. For this reason, the number of parts can be reduced, and the increase in parts management cost and assembly work cost can be suppressed.
Further, if the conductive lubricant is applied to the sliding contact portion between the conductive material 18 and the seal groove 15 of the inner ring 5, the sliding property of the sliding contact portion can be improved and the sliding resistance can be reduced.

尚、上記各導電材１８は、上記シールリング１０ａを構成する弾性材１２を前記芯金１１にモールド成形する際に、キャビティー内の所定位置に設置する事により、容易に上記弾性材１２中に埋め込む事ができる。この為、大量生産に適している。
又、上記弾性材１２の材質は、前記導電性添加剤を含まないニトリルゴムやアクリルゴム、フッ素ゴム等や、ゴム材にカーボンブラック等の上記導電性添加剤を混練した導電性ゴムを採用する事ができる。但し、この導電性ゴムを使用する場合、この導電性ゴムの弾性や強度が低下し過ぎない様に、上記導電性添加剤の割合を適度に調整する。 Each of the conductive members 18 can be easily placed in the elastic member 12 by placing the elastic member 12 constituting the seal ring 10a at a predetermined position in the cavity when the core member 11 is molded. Can be embedded in For this reason, it is suitable for mass production.
The elastic material 12 is made of nitrile rubber, acrylic rubber, fluorine rubber or the like that does not contain the conductive additive, or conductive rubber obtained by kneading the conductive additive such as carbon black in a rubber material. I can do things. However, when this conductive rubber is used, the proportion of the conductive additive is appropriately adjusted so that the elasticity and strength of the conductive rubber do not decrease excessively.

［実施の形態の第２例］
図３は、請求項１〜３、６〜８に対応する、本発明の実施の形態の第２例を示している。本例の玉軸受１ｂを構成するシールリング１０ｂは、このシールリング１０ｂの径方向内端部に形成しているシールリップ１４ａの先端に、全周に亙って凹溝２２を形成している。又、この凹溝２２の両側部分を、それぞれ内輪５の両端部外周面に形成したシール溝１５の側壁面に、全周に亙って摺接させている。そして、この様なシールリング１０ｂに、外輪３と内輪５とを電気的に導通する為の導通機構１９ａを設けている。 [Second Example of Embodiment]
FIG. 3 shows a second example of an embodiment of the present invention corresponding to claims 1 to 3 and 6 to 8. In the seal ring 10b constituting the ball bearing 1b of this example, a groove 22 is formed over the entire circumference at the tip of the seal lip 14a formed at the radially inner end of the seal ring 10b. . Further, both side portions of the concave groove 22 are slidably brought into contact with the side wall surfaces of the seal grooves 15 formed on the outer peripheral surfaces of both ends of the inner ring 5 over the entire circumference. The seal ring 10b is provided with a conduction mechanism 19a for electrically conducting the outer ring 3 and the inner ring 5.

この導通機構１９ａは、上記シールリング１０ｂを構成する弾性材１２ａ中に、可撓性及び導電性を有する導電材１８ａを包埋保持する事で構成している。そして、これら各導電材１８ａの径方向外端部をこの弾性材１２ａの径方向外端部に設けている突出部１３の径方向外端縁から露出させて上記外輪３の両端部内周面にそれぞれ全周に亙って形成した係止溝９に、直接導通させている。又、上記各導電材１８ａの径方向内端部を上記凹溝２２の両側部分から露出させる事で、上記内輪５のシール溝１５に、直接導通させている。この様にして、上記外輪３と上記内輪５とを電気的に導通させている。 The conduction mechanism 19a is configured by embedding and holding a conductive material 18a having flexibility and conductivity in the elastic material 12a constituting the seal ring 10b. And the radial direction outer end part of each of these conductive materials 18a is exposed from the radial direction outer end edge of the protrusion part 13 provided in the radial direction outer end part of this elastic material 12a, and it is on the inner peripheral surface of the both ends of the said outer ring | wheel 3 Each is directly conducted to a locking groove 9 formed over the entire circumference. Further, by exposing the radially inner end portions of the respective conductive materials 18 a from both side portions of the concave groove 22, the conductive material 18 a is directly conducted to the seal groove 15 of the inner ring 5. In this way, the outer ring 3 and the inner ring 5 are electrically connected.

この様な本例の通電式玉軸受１ｂの場合、上記内輪５のシール溝１５と上記各導電材１８ａの径方向内端部とが、それぞれ上記凹溝２２の両側部分の２個所位置で摺接している。この為、電気的な導通性の向上を図る事ができる。その他の部分の構成及び作用に就いては、上述した実施の形態の第１例と同様であるから、重複する説明は省略する。 In the case of such a current-carrying ball bearing 1b of this example, the seal groove 15 of the inner ring 5 and the radially inner end of each conductive material 18a are slid at two positions on both sides of the concave groove 22, respectively. It touches. For this reason, electrical continuity can be improved. Since the configuration and operation of the other parts are the same as those in the first example of the above-described embodiment, redundant description is omitted.

［実施の形態の第３例］
図４は、請求項１〜４、６〜８に対応する、本発明の実施の形態の第３例を示している。本例の玉軸受１ｃの基本構造は、上述した実施の形態の第２例と同様である。但し、シールリング１０ｂを構成するシールリップ１４ａの先端に全周に亙って設けている凹溝２２の内面と、内輪５の両端部外周面に形成したシール溝１５とに囲まれている環状空間に、図４に梨地で示す導電性潤滑剤２３を封入している。この導電性潤滑剤２３は、基油にカーボンブラック等の導電性添加剤を添加した導電性グリース等を使用している。
又、上記シールリング１０ｂを構成する弾性材１２ａには、ゴム剤に導電性添加剤を混練した導電性ゴムを使用している。 [Third example of embodiment]
FIG. 4 shows a third example of the embodiment of the invention corresponding to claims 1-4 and 6-8. The basic structure of the ball bearing 1c of this example is the same as the second example of the embodiment described above. However, an annular shape surrounded by the inner surface of the concave groove 22 provided over the entire circumference at the tip of the seal lip 14a constituting the seal ring 10b and the seal grooves 15 formed on the outer peripheral surfaces of both ends of the inner ring 5 is provided. In the space, a conductive lubricant 23 shown in satin in FIG. 4 is enclosed. As the conductive lubricant 23, conductive grease or the like in which a conductive additive such as carbon black is added to the base oil is used.
The elastic material 12a constituting the seal ring 10b is made of conductive rubber in which a conductive additive is kneaded with a rubber agent.

この様な本例の通電式玉軸受１ｃの場合、上記環状空間に導電性潤滑剤２３を封入している為、上記各導電材１８ａと上記内輪５のシール溝１５との摺接部での摺動性を向上し、摺動抵抗を低減できる。又、上記導電性潤滑剤２３と上記弾性材１２ａとは共に導電性を備えている為、電気的な導通性の向上を図る事ができる。その他の部分の構成及び作用に就いては、上述した実施の形態の第２例と同様であるから、重複する説明は省略する。 In the case of the current-carrying ball bearing 1c of this example, since the conductive lubricant 23 is enclosed in the annular space, the sliding contact portion between the conductive material 18a and the seal groove 15 of the inner ring 5 is used. Slidability can be improved and sliding resistance can be reduced. In addition, since both the conductive lubricant 23 and the elastic material 12a have conductivity, it is possible to improve electrical conductivity. Since the configuration and operation of the other parts are the same as in the second example of the above-described embodiment, overlapping description is omitted.

［実施の形態の第４例］
図５は本発明の対象である、通電式玉軸受１ｄを示している。この玉軸受１ｄを構成するシールリング１０ｃは、このシールリング１０ｃの径方向内端部に形成しているシールリップ１４ａの先端に全周に亙って凹溝２２を形成している。又、この凹溝２２の両側部分を、それぞれ内輪５の両端部外周面に形成したシール溝１５の側壁面に全周に亙って摺接させている。そして、この様なシールリング１０ｃに、外輪３と内輪５とを電気的に導通する為の導通機構１９ｂを設けている。 [Fourth Example of Embodiment]
FIG. 5 shows a current-carrying ball bearing 1d which is an object of the present invention. In the seal ring 10c constituting the ball bearing 1d, a groove 22 is formed over the entire circumference at the tip of a seal lip 14a formed at the radially inner end of the seal ring 10c. Further, both side portions of the concave groove 22 are in sliding contact with the side wall surfaces of the seal grooves 15 formed on the outer peripheral surfaces of both ends of the inner ring 5 over the entire circumference. The seal ring 10c is provided with a conduction mechanism 19b for electrically conducting the outer ring 3 and the inner ring 5.

この導通機構１９ｂは、上記シールリング１０ｃを構成する弾性材１２ａ中に、可撓性及び導電性を有する導電材１８ｂを包埋保持する事で構成している。そして、これら各導電材１８ｂの径方向外端部をこの弾性材１２ａの径方向外端部に設けている突出部１３の径方向外端縁から露出させて、上記外輪３の両端部内周面にそれぞれ全周に亙って形成した係止溝９に、直接導通させている。又、上記各導電材１８ｂの径方向内端部を上記凹溝２２の内面の一部に露出させている。又、この凹溝２２の内面と上記内輪５のシール溝１５とに囲まれる環状空間に、図５に梨地で示す導電性潤滑剤２３を封入している。この為、上記各導電材１８ａと上記内輪５のシール溝１５の内面とは、この導電性潤滑剤２３を介して電気的に導通している。尚、この導電性潤滑剤２３は、基油にカーボンブラック等の導電性添加剤を添加した導電性グリース等を使用している。又、上記弾性材１２ａは、ゴム材に上記導電性添加剤を混練した導電性ゴムにより構成している。この様にして、上記外輪３と上記内輪５とを上記導通機構１９ｂにより電気的に導通させている。 The conduction mechanism 19b is configured by embedding and holding a conductive material 18b having flexibility and conductivity in the elastic material 12a constituting the seal ring 10c. Then, the radially outer end portions of the respective conductive materials 18b are exposed from the radially outer end edges of the protruding portions 13 provided at the radially outer end portions of the elastic material 12a, and the inner peripheral surfaces of both end portions of the outer ring 3 are exposed. In addition, each is directly connected to a locking groove 9 formed over the entire circumference. Further, the radially inner end portion of each conductive material 18b is exposed to a part of the inner surface of the concave groove 22. Further, a conductive lubricant 23 shown by a matte surface in FIG. 5 is sealed in an annular space surrounded by the inner surface of the concave groove 22 and the seal groove 15 of the inner ring 5. Therefore, each conductive material 18 a and the inner surface of the seal groove 15 of the inner ring 5 are electrically connected via the conductive lubricant 23. The conductive lubricant 23 uses conductive grease or the like in which a conductive additive such as carbon black is added to the base oil. The elastic member 12a is made of conductive rubber obtained by kneading the conductive additive in a rubber material. In this way, the outer ring 3 and the inner ring 5 are electrically connected by the conduction mechanism 19b.

この様な本例の通電式玉軸受１ｄの場合、上記内輪５のシール溝１５と上記各導電材１８ｂの径方向内端部とは上記導電性潤滑剤２３を介して電気的に導通している為、電気的な導通性を確保しながら、摩擦抵抗を低減し摺動性の向上を図る事ができる。その他の部分の構成及び作用に就いては、上述した実施の形態の第１例と同様であるから、重複する説明は省略する。 In the case of the current-carrying ball bearing 1d of this example, the seal groove 15 of the inner ring 5 and the radially inner end of each conductive material 18b are electrically connected via the conductive lubricant 23. Therefore, it is possible to reduce frictional resistance and improve slidability while ensuring electrical continuity. Since the configuration and operation of the other parts are the same as those in the first example of the above-described embodiment, redundant description is omitted.

本発明は、上述した実施の形態の第１〜４例の様な玉軸受に限らず、外部から電流が流れ込む環境で使用されるあらゆる転がり軸受に採用する事で、同様の効果を得る事ができる。 The present invention is not limited to the ball bearings as in the first to fourth examples of the embodiment described above, but can be used for any rolling bearing used in an environment where current flows from the outside, thereby obtaining the same effect. it can.

本発明の実施の形態の第１例を示す、通電式玉軸受の部分断面図。The fragmentary sectional view of the electricity supply type ball bearing which shows the 1st example of embodiment of this invention. 同じく、（Ａ）は導電材の配置に関する説明の為の、（Ｂ）は良好な導通性を確保する為の導電材の接続構造を説明する為の、それぞれ模式図。Similarly, (A) is a schematic diagram for explaining the arrangement of the conductive material, and (B) is a schematic diagram for explaining the connection structure of the conductive material for ensuring good conductivity. 本発明の実施の形態の第２例を示す、通電式玉軸受の部分断面図。The fragmentary sectional view of the electricity supply type ball bearing which shows the 2nd example of embodiment of this invention. 同第３例を示す、通電式玉軸受の部分断面図。The fragmentary sectional view of the energization type ball bearing which shows the 3rd example. 同第４例を示す、通電式玉軸受の部分断面図。The fragmentary sectional view of the energization type ball bearing which shows the 4th example. 従来構造の玉軸受の部分断面図。The fragmentary sectional view of the ball bearing of conventional structure.

符号の説明Explanation of symbols

１、１ａ、１ｂ、１ｃ、１ｄ玉軸受
２外輪軌道
３外輪
４内輪軌道
５内輪
６玉
７、７ａ保持器
８ポケット
９係止溝
１０、１０ａ、１０ｂ、１０ｃシールリング
１１芯金
１２、１２ａ弾性材
１３突出部
１４、１４ａシールリップ
１５シール溝
１６環状空間
１７導通部
１８、１８ａ、１８ｂ導電材
１９、１９ａ、１９ｂ導通機構
２０円輪状導電材
２１転動面
２２凹溝
２３導電性潤滑剤 DESCRIPTION OF SYMBOLS 1, 1a, 1b, 1c, 1d Ball bearing 2 Outer ring track 3 Outer ring 4 Inner ring track 5 Inner ring 6 Ball 7, 7a Cage 8 Pocket 9 Locking groove 10, 10a, 10b, 10c Seal ring 11 Core metal 12, 12a Elasticity Material 13 Protruding part 14, 14a Seal lip 15 Seal groove 16 Annular space 17 Conducting part 18, 18a, 18b Conductive material 19, 19a, 19b Conducting mechanism
20 Ring-shaped conductive material 21 Rolling surface 22 Concave groove 23 Conductive lubricant

Claims

内周面に外輪軌道を設けられた外輪と、外周面に内輪軌道を設けられた内輪と、これら外輪軌道と内輪軌道との間に転動自在に設けられた複数個の転動体と、上記外輪の内周面と上記内輪の外周面との間に存在してこれら各転動体を設置した軸受内部空間の端部開口を塞ぐ為の、円輪状のシールリングとを備え、このシールリングの内外両周縁のうちの一方の周縁を、上記内輪の端部と上記外輪の端部とのうちの一方の端部に全周に亙って係止すると共に、上記内外両周縁のうちの他方の周縁を、上記内輪の端部と上記外輪の端部とのうちの他方の端部の表面に全周に亙って摺接させ、更に、上記シールリングを介して、上記外輪と上記内輪とを電気的に導通させた通電式転がり軸受に於いて、このシールリングを構成する弾性材中に、可撓性及び導電性を有する導電材を包埋保持し、この導電材の両端を上記外輪と上記内輪とに、それぞれ電気的に導通させた事を特徴とする通電式転がり軸受。 An outer ring provided with an outer ring raceway on an inner peripheral surface, an inner ring provided with an inner ring raceway on an outer peripheral surface, a plurality of rolling elements provided between the outer ring raceway and the inner ring raceway so as to be freely rollable, and An annular seal ring is provided between the inner peripheral surface of the outer ring and the outer peripheral surface of the inner ring to close the end opening of the bearing inner space where the rolling elements are installed. One of the inner and outer peripheral edges is locked to one end of the inner ring end and the outer ring end over the entire circumference, and the other of the inner and outer peripheral edges. Of the inner ring and the end of the outer ring are brought into sliding contact with the surface of the other end of the inner ring and the outer ring, and the outer ring and the inner ring are interposed via the seal ring. In the energization type rolling bearing which is electrically connected to each other, the elastic material constituting the seal ring is flexible. And a conductive material having conductivity embedded hold, both ends of the conductive material and the outer ring and the inner ring, respectively energizing type rolling bearing, characterized in that were electrically conductive.

導電材の両端を弾性材の外周縁部と内周縁部とにそれぞれ露出させて、この導電材の両端部を外輪及び内輪に、直接導通させた、請求項１に記載した通電式転がり軸受。 The energization type rolling bearing according to claim 1, wherein both ends of the conductive material are exposed to an outer peripheral edge and an inner peripheral edge of the elastic material, respectively, and both ends of the conductive material are directly connected to the outer ring and the inner ring.

弾性材の内外両周縁のうちの他方の周縁に形成されたシールリップの先端に全周に亙って形成された凹溝の両側部分が、それぞれ他方の表面に全周に亙って摺接しており、導電材の端部がこの凹溝の両側部分にそれぞれ露出している、請求項２に記載した通電式転がり軸受。 Both side portions of the groove formed over the entire circumference at the tip of the seal lip formed on the other edge of the inner and outer edges of the elastic material are in sliding contact with the other surface over the entire circumference. The energization type rolling bearing according to claim 2, wherein ends of the conductive material are exposed at both side portions of the concave groove.

凹溝と他方の表面とに囲まれる空間内に導電性を有する潤滑剤を封入している、請求項３に記載した通電式転がり軸受。 The energization type rolling bearing according to claim 3, wherein a conductive lubricant is sealed in a space surrounded by the concave groove and the other surface.

弾性材の他方の周縁に形成されたシールリップの先端に全周に亙って形成された凹溝の両側部分が、それぞれ他方の面に全周に亙って摺接しており、この凹溝と他方の面とに囲まれる空間内に導電性を有する潤滑剤を封入しており、導電材の一端部をこの凹溝の内面の一部に露出させて、この導電材の一端部を上記潤滑剤を介して上記他方の面と導通させている、請求項１に記載した通電式転がり軸受。 Both side portions of the groove formed over the entire circumference at the tip of the seal lip formed on the other peripheral edge of the elastic material are in sliding contact with the other surface over the entire circumference. And the other surface are filled with a conductive lubricant, one end of the conductive material is exposed to a part of the inner surface of the groove, and the one end of the conductive material is The energization type rolling bearing according to claim 1, wherein the energization type rolling bearing is electrically connected to the other surface via a lubricant.

導電材が線状である、請求項１〜５のうちの何れか１項に記載した通電式転がり軸受。 The energization type rolling bearing according to any one of claims 1 to 5, wherein the conductive material is linear.

導電材がシート状である、請求項１〜５のうちの何れか１項に記載した通電式転がり軸受。 The energization type rolling bearing according to any one of claims 1 to 5, wherein the conductive material has a sheet shape.

導電材がメッシュ状である、請求項１〜５のうちの何れか１項に記載した通電式転がり軸受。 The energization type rolling bearing according to any one of claims 1 to 5, wherein the conductive material has a mesh shape.