JP2019152262A - Boot for constant velocity universal joint - Google Patents

Abstract

To prevent damage and breakage caused by an excessive bending angle in carrying and assembling a constant velocity universal joint, in a boot for the constant velocity universal joint of the compact shape, easy in reduction of a capacity.SOLUTION: In a boot 5 composed of a large-diameter cylindrical portion 6 mounted on an outer joint member 1 of a constant velocity universal joint, a small-diameter cylindrical portion 7 mounted on a driving-side shaft 2, and a bent portion 8 bent into the projecting shape toward the outer joint member 1 between the large-diameter cylindrical portion 6 and the small-diameter cylindrical portion 7, a crest portion 6d bent into the projecting shape toward a radial outer side, is formed on an intermediate portion 6c of the large-diameter cylindrical portion 6, and a region opposed to an inclination direction of a shaft center of the driving-side shaft 2, of the intermediate portion 6c of the large-diameter cylindrical portion 6 is deformed to the radial outer side when the outer joint member 1 and the driving-side shaft 2 are relatively bent, thus the bent portion 8 is hardly damaged and broken by being held between the outer joint member 1 and the driving-side shaft 2 in carrying and assembling the constant velocity universal joint.SELECTED DRAWING: Figure 2

Description

本発明は、等速自在継手に装着され、等速自在継手の潤滑剤の漏れおよび継手外部からの異物の侵入を防止する等速自在継手用ブーツに関する。   The present invention relates to a boot for a constant velocity universal joint that is attached to a constant velocity universal joint and prevents leakage of lubricant in the constant velocity universal joint and intrusion of foreign matter from the outside of the joint.

自動車や各種産業機械に用いられる動力伝達装置である等速自在継手（以下、単に「継手」とも称する。）は、駆動側シャフトと従動側シャフトの間に設けられ、両シャフトの軸心が一致しない（作動角が取られている）場合でも、駆動側シャフトから従動側シャフトへ速度差なく回転を伝達するものであり、そのうちの一方のシャフト（以下、「第１のシャフト」と称する。）に一体回転可能に連結される外側継手部材と、外側継手部材の径方向内側に配され、他方のシャフト（以下、「第２のシャフト」と称する。）に一体回転可能に連結される内側継手部材と、外側継手部材と内側継手部材との間でトルク伝達を行うトルク伝達機構とを備えている。   A constant velocity universal joint (hereinafter also simply referred to as “joint”), which is a power transmission device used in automobiles and various industrial machines, is provided between a drive side shaft and a driven side shaft, and the shaft centers of both shafts coincide with each other. Even when the operation is not performed (when the operating angle is taken), the rotation is transmitted from the drive side shaft to the driven side shaft without a speed difference, and one of the shafts (hereinafter referred to as “first shaft”). And an inner joint that is arranged radially inside the outer joint member and is connected to the other shaft (hereinafter referred to as “second shaft”) so as to be integrally rotatable. A member, and a torque transmission mechanism that transmits torque between the outer joint member and the inner joint member.

そして、通常は、その性能が長期間にわたって確保されるように、継手内部に潤滑剤としてのグリースを充填し、ゴム等の柔軟性のある材料で形成された等速自在継手用ブーツ（以下、単に「ブーツ」とも称する。）を装着して、グリースの継手外部への漏れを防止するとともに、継手外部から継手内部へダストや水等の異物が侵入しないようにしている。このブーツには、等速自在継手の挙動に追従できるように蛇腹形状に形成されたものが用いられることが多い。   And, normally, in order to ensure its performance over a long period of time, grease as a lubricant is filled inside the joint, and a constant velocity universal joint boot (hereinafter referred to as a rubber) is formed of a flexible material such as rubber. It is also referred to as “boots”) to prevent grease from leaking to the outside of the joint and to prevent foreign matters such as dust and water from entering the joint from the outside of the joint. In many cases, the boot is formed in a bellows shape so as to follow the behavior of the constant velocity universal joint.

ところで、蛇腹形状のブーツを装着した等速自在継手では、そのブーツの容量すなわち継手内部の空間容積が大きいことにより、継手内部のグリースの封入量がベアリング等の他の機械部品と比較しても多量となりやすい。グリースの封入量が多くなると、特に高速回転時に、その遠心力によってグリースが外径側に寄ることも重なり、ブーツの膨張変形量が大きくなってブーツが破損しやすくなることから、回転数の上限値を抑えざるをえないという問題があった。   By the way, in a constant velocity universal joint equipped with a bellows-shaped boot, the volume of the boot, that is, the space volume inside the joint, is large, so that the amount of grease inside the joint is smaller than that of other mechanical parts such as bearings. It tends to be large. When the amount of grease is increased, especially when rotating at high speed, the centrifugal force also causes the grease to move closer to the outer diameter side, which increases the amount of expansion deformation of the boot and easily damages the boot. There was a problem that the value had to be suppressed.

一方、例えば特許文献１等においては、等速自在継手用ブーツとして、蛇腹形状のものに比べてかなりコンパクト化されたものが提案されている。このようなコンパクト化されたブーツの等速自在継手への装着状態の一例を図７に示す。この図７の等速自在継手は、第１のシャフトとしての従動側シャフトが一体に形成された外側継手部材１と、外側継手部材１の径方向内側に配され、第２のシャフトとしての駆動側シャフト２の一端部に一体回転可能に連結される内側継手部材３と、両継手部材１、３間でトルク伝達を行うトルク伝達機構４とを備えている。そのトルク伝達機構４は、両継手部材１、３間に組み込まれる複数のボール４１と、各ボール４１を等間隔で回転自在に保持するケージ４２とからなる。そして、外側継手部材１の内部にグリース（図示省略）が充填されており、そのグリースを封入するブーツ５５が装着されている。   On the other hand, for example, Patent Document 1 proposes a boot that is considerably compact as compared with a bellows-shaped boot for a constant velocity universal joint. An example of a state in which such a compact boot is mounted on the constant velocity universal joint is shown in FIG. The constant velocity universal joint of FIG. 7 is arranged on the radially inner side of the outer joint member 1 in which the driven shaft as the first shaft is integrally formed and the outer joint member 1, and is driven as the second shaft. An inner joint member 3 connected to one end of the side shaft 2 so as to be integrally rotatable, and a torque transmission mechanism 4 for transmitting torque between the both joint members 1 and 3 are provided. The torque transmission mechanism 4 includes a plurality of balls 41 incorporated between the joint members 1 and 3 and a cage 42 that rotatably holds the balls 41 at equal intervals. And the grease (illustration omitted) is filled in the inside of the outer joint member 1, and the boot 55 which encloses the grease is mounted | worn.

ブーツ５５は、外側継手部材１の開口側の外周に取り付けられる大径筒部５６と、駆動側シャフト２の外周に取り付けられる小径筒部５７と、これらの両筒部５６、５７の間で外側継手部材１に向かって凸状に屈曲する屈曲部５８とからなり、従来の蛇腹形状のブーツに比べて容量を小さくしやすいコンパクトな形状となっている。なお、その大径筒部５６および小径筒部５７は、それぞれ環状の金属製ブーツバンド５９、６０で締め付けられて、外側継手部材１および駆動側シャフト２に固定されている。   The boot 55 includes a large-diameter cylindrical portion 56 that is attached to the outer periphery of the outer joint member 1 on the opening side, a small-diameter cylindrical portion 57 that is attached to the outer periphery of the driving-side shaft 2, and an outer side between these cylindrical portions 56 and 57. It consists of a bent portion 58 that bends in a convex shape toward the joint member 1, and has a compact shape that makes it easier to reduce the capacity compared to a conventional bellows-shaped boot. The large-diameter cylindrical portion 56 and the small-diameter cylindrical portion 57 are fixed to the outer joint member 1 and the drive-side shaft 2 by being fastened by annular metal boot bands 59 and 60, respectively.

特許第５２９５３６４号公報Japanese Patent No. 5295364

上記のようにコンパクト化されたブーツ５５を装着した等速自在継手では、従来の蛇腹形状のブーツを装着したものに比べて、ブーツ５５の容量を小さくできる分だけ、継手内部のグリースの封入量が少なくなり、高速回転時にも遠心力によるブーツ５５の膨張変形量が小さくなってブーツ５５が破損しにくくなることから、回転数の上限値を高く設定することができる。   In the constant velocity universal joint equipped with the compacted boot 55 as described above, the amount of grease filled inside the joint is reduced by the amount that the capacity of the boot 55 can be reduced as compared with the conventional joint having the bellows-shaped boot. Since the amount of expansion and deformation of the boot 55 due to centrifugal force is reduced and the boot 55 is less likely to be damaged even during high-speed rotation, the upper limit value of the rotational speed can be set high.

しかしながら、図８に示すように、外側継手部材１と駆動側シャフト２とが相対的に折り曲げられて（傾動して）、外側継手部材１の軸心と駆動側シャフト２の軸心とのなす折り曲げ角度αが大きくなると、ブーツ５５の屈曲部５８のうち、駆動側シャフト２の軸心の傾斜方向と対向する部位が外側継手部材１と駆動側シャフト２の間に挟まれて、損傷・破損してしまうという問題がある。   However, as shown in FIG. 8, the outer joint member 1 and the drive-side shaft 2 are relatively bent (tilted) to form the axis of the outer joint member 1 and the axis of the drive-side shaft 2. When the bending angle α is increased, a portion of the bent portion 58 of the boot 55 that is opposed to the inclination direction of the axis of the drive side shaft 2 is sandwiched between the outer joint member 1 and the drive side shaft 2 to be damaged or broken. There is a problem of end up.

ここで、上記の折り曲げ角度は、等速自在継手を自動車等に組み込んだ後は設計した作動角の最大値よりも大きくなることはないが、等速自在継手の組込前の運搬時や組込作業時に作動角最大値よりも大きくなることがあり、このような場合にブーツの損傷・破損が生じやすい。   Here, the above-mentioned bending angle does not become larger than the designed maximum operating angle after the constant velocity universal joint is incorporated in an automobile or the like. The operating angle may become larger than the maximum operating angle during the loading operation, and in such a case, the boot is easily damaged or broken.

このため、このような等速自在継手に対しては、ブーツを装着してから自動車等への組込作業が完了するまで、折り曲げ角度が過度に大きくならないように細心の注意を払って取り扱う必要があり、これが作業者にとって負担となっていた。   For this reason, it is necessary to handle such constant velocity universal joints with great care so that the bending angle does not become excessively large from the time when the boots are mounted to the time when the assembly work to the automobile is completed. This was a burden on the workers.

また、運搬中のブーツの損傷・破損を防止するために、等速自在継手に折り曲げ角度を規制するための緩衝材を挟ませる対策や、等速自在継手の組立ラインの終端を自動車等への組み込みを行う作業場所の近傍に配置して運搬距離を短くする対策がとられている場合もあるが、前者の対策は緩衝材の着脱等が作業負荷の増大につながり、後者の対策は組立ラインのレイアウトの制約につながりやすい。   In addition, in order to prevent damage and breakage of boots during transportation, measures to put a cushioning material to regulate the bending angle in the constant velocity universal joint, and the end of the assembly line of the constant velocity universal joint to the automobile etc. In some cases, measures have been taken to reduce the transport distance by placing it near the work place to be assembled. However, the former measure leads to an increase in the work load due to the attachment and detachment of cushioning materials, etc. The latter measure is an assembly line. It is easy to lead to the restrictions of the layout.

そこで、本発明は、容量を小さくしやすいコンパクトな形状の等速自在継手用ブーツにおいて、等速自在継手の運搬・組込時の過大な折り曲げ角度に起因する損傷・破損を防止することを課題とする。   Accordingly, the present invention has an object to prevent damage and breakage caused by an excessive bending angle during transportation and incorporation of a constant velocity universal joint in a compact constant velocity universal joint boot that easily reduces the capacity. And

上記の課題を解決するために、本発明は、外側継手部材と、前記外側継手部材の径方向内側に配され、シャフトに一体回転可能に連結される内側継手部材と、前記外側継手部材と内側継手部材との間でトルク伝達を行うトルク伝達機構とを備えた等速自在継手に対して適用され、前記外側継手部材の外周に取り付けられる大径筒部と、前記シャフトの外周に取り付けられる小径筒部と、前記大径筒部と小径筒部の間で前記外側継手部材に向かって凸状に屈曲する屈曲部とを備えた等速自在継手用ブーツにおいて、前記大径筒部は、前記外側継手部材の外周面に固定される取付部と、前記屈曲部の外側端部に連続する接続部と、前記取付部と接続部の間で軸方向に延びる中間部とからなり、前記中間部は、前記外側継手部材の軸心に対して前記シャフトの軸心が相対的に傾斜したときに、前記シャフトの軸心の傾斜方向と対向する部位が径方向外側へ変形する形状に形成されている構成を採用した。   In order to solve the above-described problems, the present invention provides an outer joint member, an inner joint member that is arranged radially inside the outer joint member and is connected to a shaft so as to be integrally rotatable, the outer joint member, and an inner side. Applied to a constant velocity universal joint having a torque transmission mechanism for transmitting torque to and from a joint member, and a large-diameter cylindrical portion attached to the outer periphery of the outer joint member, and a small diameter attached to the outer periphery of the shaft In the constant velocity universal joint boot comprising a cylindrical portion and a bent portion that is bent convexly toward the outer joint member between the large diameter cylindrical portion and the small diameter cylindrical portion, the large diameter cylindrical portion is The intermediate portion comprises an attachment portion fixed to the outer peripheral surface of the outer joint member, a connection portion continuous to the outer end portion of the bent portion, and an intermediate portion extending in the axial direction between the attachment portion and the connection portion. Is about the axis of the outer joint member When the axis of Yafuto is relatively inclined, and employs a configuration that portion which is inclined direction facing the axis of the shaft is shaped to deform radially outward.

上記の構成によれば、等速自在継手の運搬や自動車等への組み込みを行う際に、外側継手部材とシャフトとを相対的に折り曲げる（傾動させる）荷重が加わって、外側継手部材の軸心とシャフトの軸心とのなす折り曲げ角度が設計上の作動角最大値よりも大きくなっても、大径筒部の中間部のうち、前記シャフトの軸心の傾斜方向と対向する部位が径方向外側へ変形するので、ブーツの屈曲部が外側継手部材と前記シャフトの間に挟まれて損傷・破損することを防止できる。   According to the above configuration, when the constant velocity universal joint is transported or incorporated in an automobile or the like, a load that relatively bends (tilts) the outer joint member and the shaft is applied, and the axis of the outer joint member is added. Even if the bending angle formed between the shaft and the shaft axis is larger than the designed maximum operating angle, the portion of the middle portion of the large-diameter cylindrical portion that faces the inclined direction of the shaft axis is the radial direction. Since it deform | transforms outside, it can prevent that the bending part of a boot is pinched | interposed between an outer joint member and the said shaft, and is damaged and broken.

ここで、前記大径筒部の中間部の具体的な構成としては、径方向外側に向かって凸状に屈曲する山部を少なくとも１つ有しているか、あるいは、径方向外側に向かって凹状に屈曲する谷部を少なくとも１つ有しているものとすることができる。   Here, as a specific configuration of the intermediate portion of the large-diameter cylindrical portion, it has at least one peak portion that bends in a convex shape toward the radially outer side, or a concave shape toward the radially outer side. It is possible to have at least one trough that bends.

そして、前記大径筒部の中間部を、前記山部または前記谷部が２つ以上連続する蛇腹形状に形成されている構成とすれば、外側継手部材と前記シャフトとが相対的に傾動したときに、前記シャフトの軸心の傾斜方向と対向する部位が一層変形しやすくなって、より効果的にブーツの損傷を防止することができる。   And if the intermediate part of the said large diameter cylinder part is made into the structure formed in the bellows shape in which the said peak part or the said trough part continues two or more, an outer joint member and the said shaft will incline relatively. Sometimes, the portion of the shaft facing the tilt direction of the shaft center is more easily deformed, and damage to the boot can be prevented more effectively.

また、前記大径筒部の中間部の山部または谷部の肉厚が、前記屈曲部の肉厚よりも小さく形成されている構成としても、外側継手部材とシャフトとが相対的に傾動したときの大径筒部の中間部の変形が大きくなって、より効果的にブーツの損傷を防止できるようになる。   In addition, the outer joint member and the shaft are relatively tilted even when the thickness of the peak or valley of the intermediate portion of the large-diameter cylindrical portion is smaller than the thickness of the bent portion. The deformation of the intermediate portion of the large-diameter cylindrical portion at the time becomes larger, and the boot can be more effectively prevented from being damaged.

さらに、前記小径筒部は、前記シャフトの外周面に環状のブーツバンドによって固定される取付部と、前記屈曲部の内側端部に連続する接続部と、前記取付部と接続部の間で軸方向に延びる中間部とからなり、前記中間部の外径が前記ブーツバンドの外径よりも大きく形成されているものとすることが好ましい。このようにすれば、継手の折り曲げ角度が大きくなったときの屈曲部のブーツバンドとの接触による損傷を防止することができる。   Further, the small-diameter cylindrical portion includes an attachment portion that is fixed to the outer peripheral surface of the shaft by an annular boot band, a connection portion that is continuous with an inner end portion of the bent portion, and an axis between the attachment portion and the connection portion. It is preferable that the outer diameter of the intermediate portion is larger than the outer diameter of the boot band. If it does in this way, the damage by the contact with the boot band of the bending part when the bending angle of a joint becomes large can be prevented.

本発明の等速自在継手用ブーツは、上述したように、等速自在継手の外側継手部材の軸心に対してシャフトの軸心が相対的に傾斜したときに、大径筒部の中間部のうち、シャフトの軸心の傾斜方向と対向する部位が径方向外側へ変形するようにしたものであるから、等速自在継手の運搬や自動車等への組み込みを行う際に折り曲げ角度が大きくなっても、屈曲部が外側継手部材とシャフトの間に挟まれにくく、損傷・破損を生じにくい。   As described above, the boot for a constant velocity universal joint according to the present invention has an intermediate portion of the large-diameter cylindrical portion when the shaft center of the shaft is inclined relative to the shaft center of the outer joint member of the constant velocity universal joint. Of these, the part of the shaft that faces the tilt direction of the shaft center is deformed radially outward, so that the folding angle increases when the constant velocity universal joint is transported or incorporated in an automobile or the like. However, it is difficult for the bent portion to be sandwiched between the outer joint member and the shaft, and damage or breakage is less likely to occur.

したがって、このブーツを装着した等速自在継手は、運搬・組込時の取り扱いが容易になり、緩衝材も不要となる。また、等速自在継手の組立ラインの終端を組込場所の近傍に配置する必要もなくなるので、組立ラインのレイアウトの自由度が大きくなる。   Therefore, the constant velocity universal joint equipped with this boot is easy to handle during transportation and assembly, and does not require a cushioning material. In addition, since it is not necessary to arrange the end of the assembly line of the constant velocity universal joint near the assembly location, the degree of freedom in the layout of the assembly line is increased.

第１の実施形態のブーツを装着した等速自在継手の正面断面図Front sectional view of the constant velocity universal joint equipped with the boot of the first embodiment 図１の等速自在継手の折り曲げ状態を示す正面断面図Front sectional view showing the bent state of the constant velocity universal joint of FIG. 図１のブーツの第１の変形例を示す正面断面図Front sectional drawing which shows the 1st modification of the boot of FIG. 図１のブーツの第２の変形例を示す正面断面図Front sectional drawing which shows the 2nd modification of the boot of FIG. 第２の実施形態のブーツを装着した等速自在継手の正面断面図Front sectional view of the constant velocity universal joint equipped with the boot of the second embodiment 図５の等速自在継手の折り曲げ状態を示す正面断面図Front sectional view showing the bent state of the constant velocity universal joint of FIG. 従来のブーツを装着した等速自在継手の正面断面図Front sectional view of a constant velocity universal joint with conventional boots 図７の等速自在継手の折り曲げ状態を示す正面断面図Front sectional view showing the folded state of the constant velocity universal joint of FIG.

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は第１の実施形態のブーツを装着した固定型の等速自在継手を示す。この等速自在継手は、基本的な構成は前述の図７に示したものと同じであり、第１のシャフトとしての従動側シャフトである軸部１ａを有するカップ状の外側継手部材１と、外側継手部材１の径方向内側に配され、第２のシャフトとしての駆動側シャフト２の一端部に一体回転可能に連結されるリング状の内側継手部材３と、外側継手部材１と内側継手部材３との間でトルク伝達を行うトルク伝達機構４とを備えている。   Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 6. FIG. 1 shows a fixed type constant velocity universal joint equipped with the boot of the first embodiment. The constant velocity universal joint has the same basic configuration as that shown in FIG. 7 described above, and has a cup-shaped outer joint member 1 having a shaft portion 1a which is a driven side shaft as a first shaft, A ring-shaped inner joint member 3 that is arranged on the radially inner side of the outer joint member 1 and is connected to one end of a drive-side shaft 2 as a second shaft so as to be integrally rotatable, and the outer joint member 1 and the inner joint member 3 is provided with a torque transmission mechanism 4 that performs torque transmission with the motor 3.

前記トルク伝達機構４は、外側継手部材１の内周面に形成された複数の軸方向溝１ｂと内側継手部材３の外周面に外側継手部材１の軸方向溝１ｂに対応して形成された複数の軸方向溝３ａとの間に組み込まれる複数のトルク伝達用のボール４１と、各ボール４１を等間隔で回転自在に保持するケージ４２とで構成されており、外側継手部材１と駆動側シャフト２とが相対傾動した状態で等速に回転伝達できるようになっている。   The torque transmission mechanism 4 is formed on the inner peripheral surface of the outer joint member 1 corresponding to the axial grooves 1 b of the outer joint member 1 and the outer peripheral surface of the inner joint member 3. A plurality of torque transmitting balls 41 incorporated between the plurality of axial grooves 3a and a cage 42 that rotatably holds the balls 41 at equal intervals are provided. The shaft 2 can be transmitted at a constant speed while being tilted relative to the shaft 2.

そして、外側継手部材１の内部には、潤滑剤としてのグリース（図示省略）が充填されており、そのグリースの漏れ防止および継手外部から継手内部への異物の侵入防止のために、第１の実施形態の等速自在継手用ブーツ５が装着されている。   The outer joint member 1 is filled with grease (not shown) as a lubricant. In order to prevent the grease from leaking and to prevent foreign matter from entering the joint from the outside of the joint, the first joint is used. The constant velocity universal joint boot 5 of the embodiment is mounted.

この等速自在継手用ブーツ５は、ゴム等の柔軟性のある材料で形成されており、外側継手部材１の開口側端部の外周に取り付けられる大径筒部６と、外側継手部材１から所定の軸方向距離だけ離れた位置で駆動側シャフト２の外周に取り付けられる小径筒部７と、その大径筒部６と小径筒部７を連結する屈曲部８とからなり、従来の蛇腹形状のものに比べて容量を小さくしやすいコンパクトな形状のものとなっている。そして、その大径筒部６および小径筒部７がそれぞれ環状の金属製ブーツバンド９、１０で締め付けられて、外側継手部材１の開口側端部の外周面および駆動側シャフト２の外周面に密着した状態で固定されている。   The constant velocity universal joint boot 5 is formed of a flexible material such as rubber, and is formed of a large-diameter cylindrical portion 6 attached to the outer periphery of the opening side end portion of the outer joint member 1, and the outer joint member 1. A conventional bellows shape comprising a small diameter cylindrical portion 7 attached to the outer periphery of the drive side shaft 2 at a position separated by a predetermined axial distance, and a bent portion 8 connecting the large diameter cylindrical portion 6 and the small diameter cylindrical portion 7. It has a compact shape that makes it easier to reduce the capacity compared to other types. The large-diameter cylindrical portion 6 and the small-diameter cylindrical portion 7 are fastened by annular metal boot bands 9 and 10, respectively, to the outer peripheral surface of the opening side end portion of the outer joint member 1 and the outer peripheral surface of the drive side shaft 2. It is fixed in close contact.

大径筒部６は、ブーツバンド９で外側継手部材１の外周面に固定される取付部６ａと、屈曲部８の外側端部に連続する接続部６ｂと、取付部６ａと接続部６ｂの間で軸方向に延びる中間部６ｃとからなる。また、小径筒部７は、ブーツバンド１０で駆動側シャフト２の外周面に固定される取付部７ａと、屈曲部８の内側端部に連続する接続部７ｂと、取付部７ａと接続部７ｂの間で軸方向に延びる中間部７ｃとからなる。そして、屈曲部８は、その外側端部と内側端部の間で外側継手部材１の開口に向かって凸状（Ｒ形状）に屈曲するように形成されている。   The large-diameter cylindrical portion 6 includes a mounting portion 6a that is fixed to the outer peripheral surface of the outer joint member 1 by a boot band 9, a connecting portion 6b that is continuous to the outer end portion of the bent portion 8, and a mounting portion 6a and a connecting portion 6b. And an intermediate portion 6c extending in the axial direction. The small-diameter cylindrical portion 7 includes a mounting portion 7a that is fixed to the outer peripheral surface of the drive-side shaft 2 by the boot band 10, a connecting portion 7b that is continuous with the inner end of the bent portion 8, a mounting portion 7a, and a connecting portion 7b. And an intermediate portion 7c extending in the axial direction. And the bending part 8 is formed so that it may bend in convex shape (R shape) toward the opening of the outer joint member 1 between the outer side edge part and inner side edge part.

ここで、大径筒部６の中間部６ｃには、軸方向中央よりも取付部６ａ寄りの位置に、径方向外側に向かって凸状に屈曲する山部６ｄが形成されている。これにより、図２に示すように、外側継手部材１と駆動側シャフト２とが相対的に折り曲げられて、外側継手部材１の軸心に対して駆動側シャフト２の軸心が相対的に傾斜すると、接続部６ｂと中間部６ｃは、駆動側シャフト２の軸心の傾斜方向と対向する部位が径方向外側へ変形するようになっている。なお、山部６ｄの軸方向位置は、外側継手部材１の開口端部よりも駆動側シャフト２側に配置している。   Here, the intermediate portion 6c of the large-diameter cylindrical portion 6 is formed with a peak portion 6d that is bent in a convex shape toward the radially outer side at a position closer to the attachment portion 6a than the center in the axial direction. As a result, as shown in FIG. 2, the outer joint member 1 and the drive side shaft 2 are bent relatively, and the axis of the drive side shaft 2 is inclined relative to the axis of the outer joint member 1. Then, the connection portion 6b and the intermediate portion 6c are configured such that portions facing the inclination direction of the axis of the drive side shaft 2 are deformed radially outward. In addition, the axial position of the peak portion 6d is arranged closer to the drive side shaft 2 than the opening end portion of the outer joint member 1.

この等速自在継手用ブーツ５は、上記の構成であり、等速自在継手の運搬や自動車等への組み込みを行う際に、外側継手部材１と駆動側シャフト２とを相対的に折り曲げる（傾動させる）荷重が加わって、折り曲げ角度α（図２参照）が設計上の作動角最大値よりも大きくなっても、大径筒部６の中間部６ｃのうち、山部６ｄから接続部６ｂにかかる部位が径方向外側へ変形するので、屈曲部８が外側継手部材１と駆動側シャフト２の間に挟まれず、損傷・破損を生じにくい。つまり、この場合、山部６ｄを起点として接続部６ｂと中間部６ｃが径方向外側へ変形し、さらに接続部６ｂは屈曲部８の外径端部側の一部とともに径方向外側へ変形するので、屈曲部８が外側継手部材１の開口端部内に入り込まない状態になる。   This constant velocity universal joint boot 5 has the above-described configuration, and when the constant velocity universal joint is transported or incorporated in an automobile or the like, the outer joint member 1 and the drive side shaft 2 are relatively bent (tilted). Even when the load is applied and the bending angle α (see FIG. 2) becomes larger than the designed maximum operating angle, the peak portion 6d to the connecting portion 6b in the intermediate portion 6c of the large-diameter cylindrical portion 6 Since such a portion is deformed radially outward, the bent portion 8 is not sandwiched between the outer joint member 1 and the drive side shaft 2, and damage and breakage are unlikely to occur. In other words, in this case, the connecting portion 6b and the intermediate portion 6c are deformed radially outward from the peak portion 6d, and further, the connecting portion 6b is deformed radially outward together with a part of the bent portion 8 on the outer diameter end side. Therefore, the bent portion 8 does not enter the open end portion of the outer joint member 1.

この第１の実施形態において、図３に示す第１の変形例のように、大径筒部６の中間部６ｃの山部６ｄの肉厚ｔ１を屈曲部８の肉厚ｔ２よりも小さく形成すれば、外側継手部材１と駆動側シャフト２とが相対的に傾動したとき（図２参照）の大径筒部６の中間部６ｃの変形が大きくなって、より効果的にブーツ５の損傷を防止できるようになる。   In the first embodiment, as in the first modification shown in FIG. 3, the thickness t1 of the peak portion 6d of the intermediate portion 6c of the large-diameter cylindrical portion 6 is made smaller than the thickness t2 of the bent portion 8. Then, when the outer joint member 1 and the drive side shaft 2 are relatively tilted (see FIG. 2), the deformation of the intermediate portion 6c of the large-diameter cylindrical portion 6 becomes large, and the boot 5 is more effectively damaged. Can be prevented.

また、この第１の変形例では、小径筒部７の中間部７ｃの外径Ｄ１を、小径筒部７の取付部７ａを固定するブーツバンド１０の外径Ｄ２よりも大きく形成することにより、継手の折り曲げ角度が大きくなったときの屈曲部８のブーツバンド１０との接触による損傷も防止できるようにしている。   Moreover, in this 1st modification, by forming the outer diameter D1 of the intermediate part 7c of the small diameter cylinder part 7 larger than the outer diameter D2 of the boot band 10 which fixes the attaching part 7a of the small diameter cylinder part 7, Damage caused by contact of the bent portion 8 with the boot band 10 when the bending angle of the joint becomes large can be prevented.

図４は第１の実施形態の第２の変形例を示す。この変形例は、図３に示した第１の変形例の大径筒部６の中間部６ｃに、山部６ｄに代えて、径方向外側に向かって凹状に屈曲する谷部６ｅを形成したものである。また、谷部６ｅの肉厚ｔ１’は屈曲部８の肉厚ｔ２よりも小さく形成している。このようにしても、外側継手部材１と駆動側シャフト２とが相対的に傾動したときに（図２参照）、大径筒部６の中間部６ｃの変形により屈曲部８が外側継手部材１と駆動側シャフト２の間に挟まれないようにすることができる。   FIG. 4 shows a second modification of the first embodiment. In this modified example, a valley portion 6e that bends radially outward is formed in place of the peak portion 6d in the intermediate portion 6c of the large-diameter cylindrical portion 6 of the first modified example shown in FIG. Is. Further, the thickness t1 'of the valley portion 6e is formed smaller than the thickness t2 of the bent portion 8. Even if it does in this way, when the outer joint member 1 and the drive side shaft 2 tilt relative to each other (see FIG. 2), the bent portion 8 becomes the outer joint member 1 due to the deformation of the intermediate portion 6c of the large diameter cylindrical portion 6. And the drive side shaft 2 can be prevented from being pinched.

図５は第２の実施形態のブーツを装着した等速自在継手を示す。この実施形態のブーツ５は、第１の実施形態のものをベースとし、大径筒部６の中間部６ｃを、山部６ｄが２つ連続する蛇腹形状に形成したものである。これにより、図６に示すように、外側継手部材１と駆動側シャフト２とが相対的に傾動したときに、第１の実施形態（図２）に比べて、大径筒部６の中間部６ｃのうちの、駆動側シャフト２の軸心の傾斜方向と対向する部位の変形が大きくなり、より効果的にブーツ５の損傷を防止することができる。   FIG. 5 shows a constant velocity universal joint equipped with the boot of the second embodiment. The boot 5 of this embodiment is based on the one of the first embodiment, and an intermediate portion 6c of the large-diameter cylindrical portion 6 is formed in a bellows shape in which two mountain portions 6d are continuous. Thereby, as shown in FIG. 6, when the outer joint member 1 and the drive side shaft 2 are relatively tilted, the intermediate portion of the large-diameter cylindrical portion 6 is compared with the first embodiment (FIG. 2). The deformation | transformation of the site | part which opposes the inclination direction of the axial center of the drive side shaft 2 among 6c becomes large, and can damage the boot 5 more effectively.

なお、大径筒部６の中間部６ｃに形成する山部６ｄは、３つ以上としてもよい。また、この第２実施形態でも、大径筒部６の中間部６ｃは、山部６ｄに代わる谷部が２つ以上連続する蛇腹形状に形成してもよい。   In addition, it is good also as three or more peak parts 6d formed in the intermediate part 6c of the large diameter cylinder part 6. FIG. Also in the second embodiment, the intermediate portion 6c of the large-diameter cylindrical portion 6 may be formed in a bellows shape in which two or more valley portions instead of the mountain portions 6d are continuous.

本発明は、上記各実施形態で説明したように、等速自在継手の過大な折り曲げ角度に起因するブーツの損傷・破損を防止できるので、等速自在継手の運搬・組込時の取り扱いを容易にし、緩衝材を不要とすることができる。また、等速自在継手の組立ラインの終端を組込場所の近傍に配置する対策も不要として、組立ラインのレイアウトの自由度を高めることができる。   As described in the above embodiments, the present invention can prevent the boot from being damaged or broken due to an excessive bending angle of the constant velocity universal joint, so that the constant velocity universal joint can be easily handled during transportation and assembly. In addition, a cushioning material can be dispensed with. Further, it is not necessary to take measures for disposing the end of the assembly line of the constant velocity universal joint in the vicinity of the assembly place, so that the degree of freedom of the assembly line layout can be increased.

今回開示された実施の形態はすべての点で例示であって制限的なものではないと考えられるべきである。本発明の範囲は、上記した意味ではなく、特許請求の範囲によって示され、特許請求の範囲と均等の意味および範囲内でのすべての変更が含まれることが意図される。   The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the meanings described above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

例えば、各実施形態では、ブーツの大径筒部の中間部に山部または谷部を形成したが、大径筒部の中間部の形状は、外側継手部材の軸心に対して第２のシャフトの軸心が相対的に傾斜したときに、第２のシャフトの軸心の傾斜方向と対向する部位が径方向外側へ変形するようになっていればよく、種々の変更が可能である。   For example, in each embodiment, a crest or a trough is formed in the intermediate portion of the large-diameter cylindrical portion of the boot, but the shape of the intermediate portion of the large-diameter cylindrical portion is the second relative to the axis of the outer joint member. When the shaft center of the shaft is relatively inclined, it is only necessary that the portion facing the tilt direction of the second shaft is deformed radially outward, and various modifications are possible.

１ 外側継手部材
２ 駆動側シャフト（第２のシャフト）
３ 内側継手部材
４ トルク伝達機構
５ ブーツ
６ 大径筒部
６ａ 取付部
６ｂ 接続部
６ｃ 中間部
６ｄ 山部
６ｅ 谷部
７ 小径筒部
７ａ 取付部
７ｂ 接続部
７ｃ 中間部
８ 屈曲部
９、１０ ブーツバンド
４１ ボール
４２ ケージ 1 Outer joint member 2 Drive side shaft (second shaft)
3 Inner joint member 4 Torque transmission mechanism 5 Boot 6 Large diameter cylindrical portion 6a Mounting portion 6b Connection portion 6c Intermediate portion 6d Mountain portion 6e Valley portion 7 Small diameter cylindrical portion 7a Mounting portion 7b Connection portion 7c Intermediate portion 8 Bending portion 9, 10 Boot Band 41 Ball 42 Cage

Claims (6)

外側継手部材と、前記外側継手部材の径方向内側に配され、シャフトに一体回転可能に連結される内側継手部材と、前記外側継手部材と内側継手部材との間でトルク伝達を行うトルク伝達機構とを備えた等速自在継手に対して適用され、
前記外側継手部材の外周に取り付けられる大径筒部と、前記シャフトの外周に取り付けられる小径筒部と、前記大径筒部と小径筒部の間で前記外側継手部材に向かって凸状に屈曲する屈曲部とを備えた等速自在継手用ブーツにおいて、
前記大径筒部は、前記外側継手部材の外周面に固定される取付部と、前記屈曲部の外側端部に連続する接続部と、前記取付部と接続部の間で軸方向に延びる中間部とからなり、前記中間部は、前記外側継手部材の軸心に対して前記シャフトの軸心が相対的に傾斜したときに、前記シャフトの軸心の傾斜方向と対向する部位が径方向外側へ変形する形状に形成されていることを特徴とする等速自在継手用ブーツ。 An outer joint member, an inner joint member that is arranged on the radially inner side of the outer joint member and is connected to a shaft so as to be integrally rotatable, and a torque transmission mechanism that transmits torque between the outer joint member and the inner joint member Applied to constant velocity universal joints with
A large-diameter cylindrical portion attached to the outer periphery of the outer joint member, a small-diameter cylindrical portion attached to the outer periphery of the shaft, and a convex bent toward the outer joint member between the large-diameter cylindrical portion and the small-diameter cylindrical portion. In a boot for a constant velocity universal joint provided with a bent portion,
The large-diameter cylindrical portion includes a mounting portion that is fixed to the outer peripheral surface of the outer joint member, a connection portion that is continuous with an outer end portion of the bent portion, and an intermediate portion that extends in the axial direction between the mounting portion and the connection portion. The intermediate portion is configured such that when the shaft center of the shaft is relatively inclined with respect to the shaft center of the outer joint member, the portion facing the tilt direction of the shaft shaft is radially outward. A constant velocity universal joint boot characterized by being formed into a shape that deforms into 前記大径筒部の中間部は、径方向外側に向かって凸状に屈曲する山部を少なくとも１つ有していることを特徴とする請求項１に記載の等速自在継手用ブーツ。   2. The constant velocity universal joint boot according to claim 1, wherein the intermediate portion of the large-diameter cylindrical portion has at least one peak portion that is bent in a convex shape toward the radially outer side. 前記大径筒部の中間部は、径方向外側に向かって凹状に屈曲する谷部を少なくとも１つ有していることを特徴とする請求項１に記載の等速自在継手用ブーツ。   2. The constant velocity universal joint boot according to claim 1, wherein the intermediate portion of the large-diameter cylindrical portion has at least one valley portion that is bent in a concave shape toward the radially outer side. 前記大径筒部の中間部は、前記山部または前記谷部が２つ以上連続する蛇腹形状に形成されていることを特徴とする請求項２または３に記載の等速自在継手用ブーツ。   4. The constant velocity universal joint boot according to claim 2, wherein an intermediate portion of the large-diameter cylindrical portion is formed in a bellows shape in which two or more of the peak portions or the valley portions are continuous. 前記大径筒部の中間部の山部または谷部の肉厚が、前記屈曲部の肉厚よりも小さく形成されていることを特徴とする請求項２乃至４のいずれかに記載の等速自在継手用ブーツ。   The constant velocity according to any one of claims 2 to 4, wherein a thickness of a peak portion or a trough portion of an intermediate portion of the large-diameter cylindrical portion is formed to be smaller than a thickness of the bent portion. Universal joint boots. 前記小径筒部は、前記シャフトの外周面に環状のブーツバンドによって固定される取付部と、前記屈曲部の内側端部に連続する接続部と、前記取付部と接続部の間で軸方向に延びる中間部とからなり、前記中間部の外径が前記ブーツバンドの外径よりも大きく形成されていることを特徴とする請求項１乃至５のいずれかに記載の等速自在継手用ブーツ。   The small-diameter cylindrical portion includes an attachment portion that is fixed to an outer peripheral surface of the shaft by an annular boot band, a connection portion that is continuous with an inner end portion of the bent portion, and an axial direction between the attachment portion and the connection portion. The boot for a constant velocity universal joint according to any one of claims 1 to 5, wherein the boot has a middle portion extending, and an outer diameter of the middle portion is larger than an outer diameter of the boot band.

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