JP2008240961A

JP2008240961A - Shaft coupling

Info

Publication number: JP2008240961A
Application number: JP2007084935A
Authority: JP
Inventors: Satoshi Utsunomiya; 聡宇都宮
Original assignee: NTN Corp; Bridgestone Corp; NTN Toyo Bearing Co Ltd
Current assignee: NTN Corp; Bridgestone Corp
Priority date: 2007-03-28
Filing date: 2007-03-28
Publication date: 2008-10-09

Abstract

<P>PROBLEM TO BE SOLVED: To shorten film length of a boot for holding lubricant inside, in a shaft coupling adopting a method for transmitting power between two parallel shafts via a rolling element provided at a crossing position of mutually orthogonal guide grooves. <P>SOLUTION: As the boot for blocking around a space between both rotary members 1, 2 is formed by a first sub-boot 8 bridging between an input side rotary member 1 and a retainer 4 and a second sub-boot 9 bridging between an output side rotary member 2 and the retainer 4, deformation quantity required for a sub-boot becomes smaller than a conventional boot bridging between both the rotary members 1, 2 and thus the film lengths of the respective sub-boots 8, 9 can be shortened. Thus, the size of the whole boot can be reduced and resistance against relative slide of both the rotary members 1, 2 is reduced by lowering rigidity of the sub-boots 8, 9 and thus coupling action in misalignment can be stabled. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

本発明は、互いに平行な２軸を連結して２軸間で動力を伝達する軸継手に関する。 The present invention relates to a shaft coupling that couples two parallel shafts and transmits power between the two shafts.

一般的な機械装置の２つの軸を連結して駆動側から従動側へ動力を伝達する軸継手は、連結する２軸の位置関係によって構造が異なり、２軸が１直線上にあるもの、交差するもの、互いに平行な（かつ同心でない）ものに大別される。 A shaft joint that connects two shafts of a general mechanical device and transmits power from the drive side to the driven side has a different structure depending on the positional relationship between the two shafts to be connected. And those that are parallel to each other (and not concentric).

このうちの平行な２軸を連結する軸継手として、本出願人は、平行な２軸間で互いに直交する案内溝の交差位置に配した転動体を介して動力を伝達する方式のものを提案した（特許文献１参照。）。
特開２００５−１７２２１７号公報 As a shaft coupling for connecting two parallel shafts, the present applicant proposes a method for transmitting power via rolling elements arranged at the intersections of guide grooves orthogonal to each other between the two parallel shafts. (See Patent Document 1).
JP 2005-172217 A

図７は上述した方式の軸継手の一例を示す。この軸継手は、軸方向で対向する２つの回転部材５１、５２の対向面に、複数の案内溝５３、５４を相手側の案内溝と直交するように設けて、各案内溝５３、５４交差位置に転動体５５を配するとともに、各転動体５５を保持器５６の長孔５７に収納したもので、各転動体５５が、保持器５６に回転部材径方向の移動を拘束された状態で駆動側の回転部材５１に押されることにより、案内溝５３、５４および保持器５６の長孔５７の内側を転動しながら従動側の回転部材５２を押して動力を伝達するようになっている。なお、図７は両回転部材５１、５２が同心の状態を示しているが、通常は、図８に示すように、両者の回転軸がずれた（偏心した）状態で使用される。 FIG. 7 shows an example of the shaft coupling of the above-described method. In this shaft coupling, a plurality of guide grooves 53 and 54 are provided on the opposing surfaces of the two rotating members 51 and 52 that face each other in the axial direction so as to be orthogonal to the guide groove on the other side. The rolling elements 55 are arranged at positions, and the respective rolling elements 55 are accommodated in the long holes 57 of the cage 56, and the rolling elements 55 are restrained from moving in the radial direction of the rotating member by the cage 56. By being pushed by the driving-side rotating member 51, the driven-side rotating member 52 is pushed to transmit power while rolling inside the guide holes 53 and 54 and the long hole 57 of the retainer 56. Although FIG. 7 shows a state in which both rotating members 51 and 52 are concentric, normally, as shown in FIG. 8, the rotating members 51 and 52 are used in a state where their rotational axes are deviated (eccentric).

ところで、この方式の軸継手では、図７および図８にも示したように、両回転部材５１、５２間の空間の周りを、両回転部材５１、５２に取り付けたブーツ５８で塞ぐことにより、継手内部にグリース等の潤滑材を保持して、案内溝５３、５４や保持器５６と転動体５５との接触面における摩擦低減および摩耗抑制を図るとともに、継手外部からの異物の侵入を防止することが望ましい。 By the way, in this type of shaft coupling, as shown in FIGS. 7 and 8, the space between the rotating members 51 and 52 is closed with a boot 58 attached to the rotating members 51 and 52. A lubricant such as grease is held inside the joint to reduce friction and suppress wear on the contact surfaces between the guide grooves 53 and 54 and the cage 56 and the rolling element 55, and to prevent foreign matter from entering from the outside of the joint. It is desirable.

前記ブーツ５８は、ゴム等のエラストマーで形成されており、両端部がそれぞれブーツバンド５９で回転部材５１、５２の外周部に固定され、両回転部材５１、５２が偏心したときには、その偏心に追随して両端部間の蛇腹状の膜部５８ａが大きく弾性変形するようになっている（図８参照）。 The boot 58 is formed of an elastomer such as rubber, and both ends are fixed to the outer peripheral portions of the rotating members 51 and 52 by boot bands 59 respectively. When the rotating members 51 and 52 are eccentric, the eccentricity follows the eccentricity. Thus, the bellows-like film part 58a between both ends is greatly elastically deformed (see FIG. 8).

しかしながら、上述したようなブーツを備えた軸継手では、ブーツの膜部を両回転部材の最大偏心時にも追随できる膜長に形成する必要があり、その膜長が長いために、以下のような問題点を有している。 However, in the shaft coupling provided with the boot as described above, it is necessary to form the membrane portion of the boot with a membrane length that can follow even when the rotating members are at the maximum eccentricity. Has a problem.

まず、ブーツの膜長が長いと、ブーツ膜部の遠心力による径方向外側への弾性変形（回転膨張）に対する剛性が低下してブーツが破損しやすくなる。一方、破損防止のために、ブーツの膜厚を厚くしたり材料を硬くしたりして剛性を高めると、両回転部材の偏心に伴うブーツ膜部の弾性復元力が増大し、両回転部材の相対的なスライドに対する抵抗が大きくなって、偏心時の継手動作が不安定になる場合がある。 First, when the membrane length of the boot is long, the rigidity against elastic deformation (rotational expansion) radially outward due to the centrifugal force of the boot membrane portion is reduced, and the boot is easily damaged. On the other hand, in order to prevent breakage, increasing the film thickness of the boot or hardening the material to increase the rigidity increases the elastic restoring force of the boot membrane part due to the eccentricity of both rotating members, In some cases, the resistance to relative sliding increases and the joint operation at the time of eccentricity becomes unstable.

次に、ブーツの膜長が長いほど、ブーツ内側空間の容積も大きくなり、その空間に封入されるグリース等の潤滑材の量が多くなるので、潤滑材のコストが上がるだけでなく、潤滑材がその遠心力によりブーツ膜部を径方向外側へ押圧する力が大きくなって、ブーツ膜部の回転膨張や異常変形を助長し、ブーツが破損しやすくなる。また、ブーツ内側空間の容積が大きいと、遠心力を受けた潤滑材がブーツ径方向外側へ移動することにより、継手内部の転動部（両回転部材の案内溝や保持器と転動体との接触面）等、摩擦の生じる部位の潤滑材がなくなって、これらの部位が摩耗しやすくなることがある。 Secondly, the longer the boot membrane length, the larger the volume of the space inside the boot and the greater the amount of grease and other lubricants enclosed in that space. However, the force that presses the boot membrane portion radially outward by the centrifugal force increases, which promotes rotational expansion and abnormal deformation of the boot membrane portion, and the boot is easily damaged. In addition, if the volume of the space inside the boot is large, the lubricant that receives centrifugal force moves outward in the radial direction of the boot, so that the rolling part inside the joint (the guide groove of both rotating members, the cage and the rolling element) Lubricants where friction occurs, such as contact surfaces, may be lost, and these portions may be easily worn.

さらに、ブーツの製造面では、ブーツの膜長が長いと、ブーツを金型で成形する際に、材料が金型内に回りにくいため成形品内部に空洞ができやすく、品質・歩留まりの向上が難しいという問題もある。 Furthermore, in terms of boot manufacturing, if the boot membrane length is long, when the boot is molded with a mold, it is difficult for the material to turn into the mold, so it is easy to create a cavity inside the molded product, which improves quality and yield. There is also the problem that it is difficult.

本発明の課題は、平行な２軸間で互いに直交する案内溝の交差位置に配した転動体を介して動力を伝達する方式の軸継手において、その内部に潤滑材を保持するブーツの膜長を短くすることである。 An object of the present invention is to provide a film length of a boot that holds a lubricant in a shaft coupling of a system that transmits power through rolling elements arranged at intersecting positions of guide grooves orthogonal to each other between two parallel axes. Is to shorten.

上記の課題を解決するため、本発明は、軸方向で対向し、回転軸が互いに平行でかつ同心でない状態に保持される２つの回転部材のそれぞれの対向面に、複数の案内溝を相手側の回転部材の対応する位置の案内溝と直交するように設け、前記両回転部材の案内溝が交差する位置に、各案内溝に案内されて転動する転動体を配し、これらの各転動体の回転部材径方向の移動を拘束する保持器を設けて、前記各転動体を介して前記両回転部材間で動力を伝達するようにし、前記両回転部材間の空間の周りを、両回転部材の偏心に追随して弾性変形する膜部を有するブーツで塞いだ軸継手において、前記ブーツを、前記一方の回転部材と保持器の間に掛け渡される第１サブブーツと、前記他方の回転部材と保持器の間に掛け渡される第２サブブーツとで構成するようにした。 In order to solve the above-described problems, the present invention provides a plurality of guide grooves on the opposing surface of each of the two rotating members that are opposed in the axial direction and are held in a state where the rotation axes are parallel to each other and not concentric. Rolling members which are provided so as to be orthogonal to the guide grooves at the corresponding positions of the rotating members, and which roll while being guided by the guide grooves at positions where the guide grooves of the rotating members intersect. A cage for restricting the movement of the rotating body in the radial direction of the rotating member is provided so that power is transmitted between the rotating members via the rolling elements, and the space between the rotating members is rotated in both directions. In a shaft joint closed with a boot having a membrane part that elastically deforms following the eccentricity of the member, the boot is connected to the first sub-boot that spans between the one rotating member and the cage, and the other rotating member. Second sub-boots spanned between the cage and the cage It was to be constituted in.

すなわち、従来は両回転部材間に掛け渡されていたブーツを、一方の回転部材と保持器の間の第１サブブーツと、他方の回転部材と保持器の間の第２サブブーツとに分けて掛け渡す構造とすることにより、従来のブーツに比べて、１つのサブブーツに要求される変形量が小さくなり、各サブブーツの膜長を短くできるようにしたのである。 That is, the boot that has been conventionally spanned between both rotating members is divided into a first sub-boot between one rotating member and the cage and a second sub-boot between the other rotating member and the cage. By adopting a passing structure, the amount of deformation required for one sub-boot is reduced compared to the conventional boot, and the film length of each sub-boot can be shortened.

上記の構成において、前記第１サブブーツと第２サブブーツを一体に形成し、この一体に形成されたブーツの一端部を前記一方の回転部材に、他端部を前記他方の回転部材に、中央部を前記保持器にそれぞれ固定するようにしてもよい。 In the above configuration, the first sub-boot and the second sub-boot are integrally formed, and one end of the integrally formed boot is used as the one rotating member, and the other end is used as the other rotating member. May be fixed to the cage.

また、前記各サブブーツの膜部を、それぞれ回転部材径方向に伸縮するように蛇腹状に折り畳まれたものとすれば、その膜部が凹凸の並ぶ方向に遠心力を受けるようになって、回転膨張による破損を生じにくくなる。 Further, if the membrane portion of each sub-boot is folded in a bellows shape so as to expand and contract in the radial direction of the rotating member, the membrane portion receives a centrifugal force in the direction in which the projections and depressions are arranged, and rotates. Damage due to expansion is less likely to occur.

本発明の軸継手は、上述したように、両回転部材間の空間の周りを塞ぐブーツを、一方の回転部材と保持器の間の第１サブブーツと、他方の回転部材と保持器の間の第２サブブーツとに分けて掛け渡す構造として、各サブブーツの膜長を従来のブーツよりも短くできるようにしたものであるから、ブーツ全体のコンパクト化が図れる。しかも、各サブブーツは、従来よりも膜長が短い分、回転膨張による破損のおそれが少なくなるため、膜厚を薄くしたり材料を軟らかくしたりして剛性を下げることができ、これにより両回転部材の相対的なスライドに対する抵抗を小さくして、偏心時の継手動作を安定させることができる。 As described above, the shaft coupling of the present invention is configured so that the boot that closes the space between the two rotating members is the first sub-boot between the one rotating member and the cage, and between the other rotating member and the cage. Since the structure of the second sub-boot is used to hang the sub-boots, the membrane length of each sub-boot can be made shorter than that of the conventional boot, so that the entire boot can be made compact. In addition, each sub-boot has a shorter film length than conventional ones, so there is less risk of damage due to rotational expansion, so the film thickness can be reduced or the material can be softened to reduce rigidity, thereby enabling both rotations. It is possible to reduce the resistance of the member to relative sliding and to stabilize the joint operation at the time of eccentricity.

また、ブーツ内側空間の容積も小さくなるので、潤滑材の使用量を減らしてコストの低減を図れるし、潤滑材がブーツ膜部を押圧する力が小さくなって、ブーツ膜部が回転膨張や異常変形を生じにくくなる。従って、上記と同様に、各サブブーツの剛性を下げて継手動作の安定化を図ることができる。また、継手内部の転動部等における潤滑不良を防止でき、これらの部位の摩耗の進行を抑えることができる。 In addition, since the volume of the boot inner space is also reduced, the amount of lubricant used can be reduced to reduce costs, and the force with which the lubricant presses the boot membrane is reduced, causing the boot membrane to rotate or malfunction. It becomes difficult to cause deformation. Accordingly, similarly to the above, the rigidity of each sub-boot can be lowered to stabilize the joint operation. In addition, it is possible to prevent poor lubrication in the rolling part or the like inside the joint, and to suppress the progress of wear of these parts.

さらに、ブーツ製造面では、１つのブーツあたりの膜長が短くなるため、ブーツ成形時のトラブル（空洞の発生）を抑えることができ、品質・歩留まりの向上が図れる。 Furthermore, since the film length per boot is shortened from the standpoint of boot production, it is possible to suppress troubles during the boot molding (occurrence of cavities), and to improve quality and yield.

以下、図１乃至図６に基づき、本発明の実施形態を説明する。図１乃至図４は、第１の実施形態を示す。この軸継手は、図１および図２に示すように、軸方向で対向し、回転軸が互いに平行な状態に保持される回転部材１、２と、両回転部材１、２間に配される複数の鋼球（転動体）３と、各鋼球３の回転部材径方向の移動を拘束する保持器４とを備え、各鋼球３を介して両回転部材１、２間で動力を伝達するものである。なお、図１および図２は、説明上、両回転部材１、２が同心の状態を示しているが、通常は後述するように両回転部材１、２の回転軸がずれた（偏心した）状態で使用される。 Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 6. 1 to 4 show a first embodiment. As shown in FIGS. 1 and 2, the shaft coupling is disposed between the rotating members 1 and 2, which are opposed to each other in the axial direction and whose rotating shafts are held in parallel with each other, and the rotating members 1 and 2. A plurality of steel balls (rolling elements) 3 and a cage 4 that restrains movement of each steel ball 3 in the radial direction of the rotating member are provided, and power is transmitted between the rotating members 1 and 2 via each steel ball 3. To do. 1 and 2 show the state in which both rotating members 1 and 2 are concentric for the sake of explanation, but the rotational axes of both rotating members 1 and 2 are usually deviated (eccentric) as will be described later. Used in state.

前記各回転部材１、２は、それぞれの軸部１ａ、２ａの一端に形成された円板部１ｂ、２ｂに、複数の案内溝５、６が周方向に等間隔で相手側の回転部材の対応する位置の案内溝と直交するように設けられており、各案内溝交差位置に鋼球３が組み込まれている。 Each of the rotating members 1 and 2 has a plurality of guide grooves 5 and 6 at equal intervals in the circumferential direction on the disk portions 1b and 2b formed at one ends of the shaft portions 1a and 2a. It is provided so as to be orthogonal to the guide groove at the corresponding position, and a steel ball 3 is incorporated at each guide groove intersection position.

前記保持器４は、環状に形成され、各案内溝５、６と４５度をなす方向に直線状に延びる長孔７が周方向に等間隔で複数設けられており、これらの各長孔７に鋼球３を収納している。これにより、各鋼球３は、保持器４に回転部材径方向の移動を拘束された状態で、案内溝５、６に案内されて転動するようになっている。 The retainer 4 is formed in an annular shape, and a plurality of elongated holes 7 extending linearly in a direction forming 45 degrees with the guide grooves 5 and 6 are provided at equal intervals in the circumferential direction. The steel ball 3 is housed in Thereby, each steel ball 3 is guided and guided by the guide grooves 5 and 6 in a state where the movement in the radial direction of the rotating member is restrained by the cage 4.

また、入力側回転部材１と保持器４の間には第１サブブーツ８が掛け渡され、出力側回転部材２と保持器４の間には第２サブブーツ９が掛け渡されて、これらの２つのサブブーツ８、９で両回転部材１、２間の空間の周りを塞ぐブーツが形成されており、これにより継手内部にグリース等の潤滑材を保持して、案内溝５、６や保持器４と鋼球３との接触面における摩擦低減および摩耗抑制を図るとともに、継手外部からの異物の侵入を防止している。なお、両回転部材１、２と保持器４は等速回転するため、各サブブーツ８、９には捩れ等の問題は生じない。 A first sub-boot 8 is spanned between the input side rotating member 1 and the cage 4, and a second sub-boot 9 is spanned between the output side rotating member 2 and the cage 4. A boot that closes the space between the rotating members 1 and 2 is formed by the two sub-boots 8 and 9, thereby holding a lubricant such as grease inside the joint, and guiding grooves 5 and 6 and a cage 4. In addition to reducing friction and suppressing wear on the contact surface between the ball and the steel ball 3, foreign matter from the outside of the joint is prevented. Since the rotating members 1 and 2 and the cage 4 rotate at a constant speed, the sub-boots 8 and 9 do not have problems such as twisting.

前記各サブブーツ８、９は、ゴム等のエラストマーで形成されており、それぞれの一端部がブーツバンド１０で回転部材１、２の外周部に固定され、他端部が保持器４外周に形成された環状溝に圧入固定されて、両端部間の膜部８ａ、９ａが両回転部材１、２の偏心に追随して弾性変形するようになっている（図４参照）。 Each of the sub-boots 8 and 9 is made of an elastomer such as rubber, and one end of each of the sub-boots 8 and 9 is fixed to the outer peripheral part of the rotating members 1 and 2 with a boot band 10, and the other end is formed on the outer periphery of the cage 4. The film portions 8a and 9a between the two end portions are elastically deformed by following the eccentricity of the rotating members 1 and 2 (see FIG. 4).

図３および図４は、両回転部材１、２が偏心量（両者の回転中心間の距離Ｏ_１−Ｏ_２）Ｅだけ偏心した状態を示す。このとき、各回転部材１、２と保持器４の回転中心間距離（Ｏ_１−Ｏ_３、Ｏ_２−Ｏ_３）は、それぞれＥ／√２となる。このため、従来のようにブーツを両回転部材１、２間に掛け渡す場合に比べると、ブーツ１つあたりの変形量は小さくてすむようになり、その分各サブブーツ８、９の膜長が短くなっている。 3 and 4 show a state in which both rotating members 1 and 2 are eccentric by an amount of eccentricity (distance O ₁ -O ₂ between the rotation centers of both) E. At this time, the distances (O ₁ -O ₃ , O ₂ -O ₃ ) between the rotation centers of the rotary members 1 and 2 and the cage 4 are E / √2, respectively. For this reason, the amount of deformation per boot can be reduced as compared with the case where the boot is spanned between the rotating members 1 and 2 as in the prior art, and the membrane length of each of the sub-boots 8 and 9 is shortened accordingly. It has become.

この軸継手は、上記の構成であり、入力側の回転部材１が回転すると、その案内溝５に周方向から押された鋼球３が、保持器４で回転部材径方向の移動を拘束された状態で、出力側の回転部材２の案内溝６を押すことにより、出力側回転部材２に動力が伝達される。なお、入力側回転部材１の回転方向が変わったり、両回転部材１、２の駆動側と従動側が逆になったりしても、同じメカニズムで動力伝達が行われる。 This shaft coupling has the above-described configuration. When the rotary member 1 on the input side rotates, the steel ball 3 pushed in the guide groove 5 from the circumferential direction is restrained from moving in the radial direction of the rotary member by the cage 4. In this state, the power is transmitted to the output side rotating member 2 by pushing the guide groove 6 of the output side rotating member 2. In addition, even if the rotation direction of the input side rotation member 1 is changed or the driving side and the driven side of both rotation members 1 and 2 are reversed, power transmission is performed by the same mechanism.

上記動力伝達メカニズムは、両回転部材１、２が偏心した通常の使用状態でも基本的に同じである。すなわち、図３および図４に示したように、各回転部材１、２が偏心すると、案内溝５、６の交差位置が回転部材周方向で変化し、各鋼球３が案内溝５、６および保持器４の長孔７内を転動しながら両回転部材１、２間の動力伝達を行うようになる。 The power transmission mechanism is basically the same even in a normal use state where the rotating members 1 and 2 are eccentric. That is, as shown in FIG. 3 and FIG. 4, when the rotating members 1 and 2 are eccentric, the crossing positions of the guide grooves 5 and 6 change in the circumferential direction of the rotating member, and the steel balls 3 are guided to the guide grooves 5 and 6. In addition, power is transmitted between the rotating members 1 and 2 while rolling in the long hole 7 of the cage 4.

また、この軸継手では、前述のように、各サブブーツ８、９の膜長が従来のブーツよりも短くなっているので、ブーツ全体をコンパクトに設計でき、回転膨張しにくい形状とすることができる。その結果、従来よりもブーツの膜厚を薄くしたり材料を軟らかくしたりしてブーツの剛性を下げることにより、両回転部材１、２の相対的なスライドに対する抵抗を小さくして、偏心時の継手動作の安定化を図ることができる。また、ブーツ内側空間の容積も小さくなるので、潤滑材使用量を減らせるし、潤滑材のブーツ径方向外側への移動に伴うトラブルを生じにくくすることができる。さらに、ブーツが製造しやすくなり、ブーツの品質・歩留まりの向上が図れる利点もある。 Further, in this shaft coupling, as described above, since the film length of each of the sub-boots 8 and 9 is shorter than that of the conventional boot, the entire boot can be designed compactly and can be formed into a shape that is difficult to rotate and expand. . As a result, by reducing the boot rigidity by reducing the boot thickness and softening the material compared to the prior art, the resistance to relative sliding of the rotating members 1 and 2 is reduced, and the eccentricity is reduced. The joint operation can be stabilized. Moreover, since the volume of the boot inner space is also reduced, the amount of lubricant used can be reduced, and trouble associated with the movement of the lubricant outward in the boot radial direction can be made difficult to occur. Furthermore, there is an advantage that boots can be easily manufactured and the quality and yield of the boots can be improved.

図５は第２の実施形態を示す。この実施形態では、第１実施形態の第１サブブーツ８と第２サブブーツ９を一体に形成し、この一体に形成されたブーツ１１の一端部を入力側回転部材１に、他端部を出力側回転部材２に、中央部を保持器４にそれぞれ固定している。そのブーツ１１の機能および他の部分の構成は第１実施形態と同じである。 FIG. 5 shows a second embodiment. In this embodiment, the first sub-boot 8 and the second sub-boot 9 of the first embodiment are integrally formed, and one end portion of the integrally formed boot 11 is used as the input side rotating member 1 and the other end portion is used as the output side. The rotating member 2 is fixed to the cage 4 at the center. The function of the boot 11 and the configuration of other parts are the same as those in the first embodiment.

図６は第３の実施形態を示す。この実施形態では、各サブブーツ８、９を、それぞれの膜部８ａ、９ａが回転部材径方向に伸縮するように蛇腹状に折り畳まれたものとした。これにより、サブブーツ８、９の膜部８ａ、９ａは、凹凸の並ぶ方向に遠心力を受けるようになって回転膨張による破損を生じにくくなる。従って、第１実施形態よりもブーツの剛性を下げて、継手動作をさらに安定させることができる。 FIG. 6 shows a third embodiment. In this embodiment, the sub-boots 8 and 9 are folded in a bellows shape so that the film portions 8a and 9a expand and contract in the radial direction of the rotating member. As a result, the film portions 8a and 9a of the sub-boots 8 and 9 are subjected to centrifugal force in the direction in which the irregularities are arranged, and are not easily damaged by rotational expansion. Therefore, the rigidity of the boot can be lowered as compared with the first embodiment, and the joint operation can be further stabilized.

第１実施形態の軸継手の側面図（回転軸が同心）Side view of shaft coupling of first embodiment (rotary shafts are concentric) 図１のII−II線に沿った断面図Sectional view along the line II-II in FIG. 図１の軸継手の使用状態を示す側面図（回転軸が偏心）FIG. 1 is a side view showing the usage state of the shaft coupling of FIG. 図３のIV−IV線に沿った断面図Sectional view along line IV-IV in FIG. 第２実施形態の軸継手の図２に対応する断面図Sectional drawing corresponding to FIG. 2 of the shaft coupling of 2nd Embodiment 第３実施形態の軸継手の図２に対応する断面図Sectional drawing corresponding to FIG. 2 of the shaft coupling of 3rd Embodiment 従来の軸継手の図２に対応する断面図Sectional view corresponding to FIG. 2 of a conventional shaft coupling 図７の軸継手の使用状態を示す図４に対応する断面図Sectional drawing corresponding to FIG. 4 which shows the use condition of the shaft coupling of FIG.

符号の説明Explanation of symbols

１、２回転部材
３鋼球（転動体）
４保持器
５、６案内溝
７長孔
８、９サブブーツ
８ａ、９ａ膜部
１０ブーツバンド
１１ブーツ 1, 2 Rotating member 3 Steel ball (rolling element)
4 Cage 5, 6 Guide groove 7 Long hole 8, 9 Sub boot 8 a, 9 a Membrane portion 10 Boot band 11 Boot

Claims

軸方向で対向し、回転軸が互いに平行でかつ同心でない状態に保持される２つの回転部材のそれぞれの対向面に、複数の案内溝を相手側の回転部材の対応する位置の案内溝と直交するように設け、前記両回転部材の案内溝が交差する位置に、各案内溝に案内されて転動する転動体を配し、これらの各転動体の回転部材径方向の移動を拘束する保持器を設けて、前記各転動体を介して前記両回転部材間で動力を伝達するようにし、前記両回転部材間の空間の周りを、両回転部材の偏心に追随して弾性変形する膜部を有するブーツで塞いだ軸継手において、前記ブーツを、前記一方の回転部材と保持器の間に掛け渡される第１サブブーツと、前記他方の回転部材と保持器の間に掛け渡される第２サブブーツとで構成したことを特徴とする軸継手。 A plurality of guide grooves are orthogonal to the guide grooves at corresponding positions of the counterpart rotating member on the opposing surfaces of the two rotating members that are axially opposed and are held in a state where the rotation axes are parallel to each other and not concentric. A rolling element that rolls while being guided by each guide groove at a position where the guide grooves of the two rotating members intersect with each other, and that holds the rolling members in the radial direction of the rotating member. A membrane part that elastically deforms around the space between the two rotating members following the eccentricity of the two rotating members so that power is transmitted between the two rotating members via the rolling elements. A first sub-boot that spans between the one rotating member and the cage, and a second sub-boot that spans between the other rotating member and the cage. A shaft coupling characterized by comprising

前記第１サブブーツと第２サブブーツを一体に形成し、この一体に形成されたブーツの一端部を前記一方の回転部材に、他端部を前記他方の回転部材に、中央部を前記保持器にそれぞれ固定したことを特徴とする請求項１に記載の軸継手。 The first sub-boot and the second sub-boot are integrally formed. One end of the integrally formed boot is the one rotating member, the other end is the other rotating member, and the center is the retainer. The shaft coupling according to claim 1, wherein each is fixed.

前記各サブブーツの膜部が、それぞれ回転部材径方向に伸縮するように蛇腹状に折り畳まれていることを特徴とする請求項１または２に記載の軸継手。 The shaft coupling according to claim 1 or 2, wherein the membrane portion of each sub-boot is folded in a bellows shape so as to expand and contract in the radial direction of the rotating member.