JP2005220955A - Constant velocity joint and method for assembling the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress derived thrust force by securing smooth rolling motion of a rolling element along an inner diameter part of a roller. <P>SOLUTION: Under a condition where all rolling elements 28, 28a are loaded on an inner diameter part 40 of a roller member 30 after last rolling element 28a is pressed in a gap between the rolling elements arranged in annular shape, a predetermined clearance C along a radial direction is provided between the inner diameter part 40 of the roller member 30 and outer diameter of the rolling elements 28, 28a when the adjoining rolling elements 28, 28a annularly contact each other by keystone effect. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to, for example, a constant velocity joint that connects one transmission shaft and the other transmission shaft in a driving force transmission unit of an automobile, and an assembling method thereof.

  Conventionally, in a driving force transmission unit of an automobile, a constant velocity joint that connects one transmission shaft and the other transmission shaft and transmits a rotational force to each axle is used.

  As a constant velocity joint according to this type of prior art, Patent Document 1 discloses a set of preventing rolling elements 3 (rollers, needles, etc.) from coming off at both axial ends of the cylindrical inner peripheral surface 2 of the roller 1. A plurality of rolling elements 3, one less than the total number, are arranged in series between a set of collars on the inner peripheral surface, and a space between the two ends of the series of rolling elements 3 is formed. The relationship between the minimum gap d2 of the gap and the diameter d1 of the rolling element 2 is set so that d2 <d1, and the difference (d1−d2) is set as a tightening allowance (press fit allowance) of several μm to several tens μm. The last rolling element 3a is press-fitted into the gap from the radially outer side of the cylindrical inner peripheral surface 2 of the roller 1, and a plurality of rolling elements 3 are mounted in series along the cylindrical inner peripheral surface 2 of the roller 1. The technical idea is disclosed (see FIG. 8).

  A method of arranging a plurality of rolling elements 3 in series along the cylindrical inner peripheral surface 2 of the roller 1 in this manner is called a keystone method, and the roller 1 and the rolling element 3 are integrated as an assembly that does not separate. It is said that it can be attached to the leg shaft at the same time.

Japanese Patent Laid-Open No. 10-184717

  However, in the method of assembling the rolling elements 3 disclosed in Patent Document 1, a plurality of rolling elements 3 are mounted in series along the cylindrical inner peripheral surface 2 of the roller 1 by press-fitting the last one rolling element 3a. When there is no clearance along the circumferential direction between the adjacent rolling elements 3 arranged along the cylindrical inner peripheral surface 2 of the roller 1, the rolling operation of each rolling element 3 becomes difficult. The rolling element 3 slides along the cylindrical inner peripheral surface 2 of the roller 1.

  Therefore, when the technical idea disclosed in Patent Document 1 is applied to, for example, a constant velocity joint (not shown) incorporated in a front wheel drive vehicle or an independent suspension type rear wheel drive vehicle, idling during traveling or stopping In a state where the rotational torque of the drive shaft is transmitted to the driven shaft as in the case of an angle and an axial displacement occurs between the driven shaft and the driven shaft, the rolling operation of the rolling element is difficult. Therefore, sliding friction occurs between the roller and the track groove. As a result, there is a problem that the induced thrust force induced due to the slide friction increases, and vibration is generated by the induced thrust force.

  The present invention has been made in view of the above problems, and is capable of suppressing the induced thrust force by ensuring a smooth rolling motion of the rolling elements along the inner diameter portion of the roller member. It aims at providing a joint and its assembling method.

In order to achieve the above object, the present invention provides a cylindrical outer member that is provided with a plurality of guide grooves that are spaced apart from each other and extend along the axial direction, and that is provided on an inner peripheral surface and connected to one transmission shaft. In the tripod type constant velocity joint having an inner member inserted into the inner space where the outer member opens and connected to the other transmission shaft,
A plurality of trunnions bulging toward the guide groove;
A ring-shaped roller member that contacts the guide groove and is externally fitted to the trunnion;
A plurality of rolling elements interposed between the trunnion and the roller member so as to freely roll;
At both end portions along the axial direction of the inner diameter portion of the roller member, flange portions projecting inward in the radial direction are respectively formed.
All of the rolling elements except for one are arranged in an annular shape along the inner diameter portion of the roller member, and then the last one is press-fitted into the interval between the annularly arranged rolling elements, Separation / dropping of rolling elements from the inner diameter is prevented,
A predetermined clearance is provided along the radial direction between the inner diameter portion of the roller member and the rolling element when adjacent rolling elements come into contact with each other in an annular shape due to the keystone effect.

Furthermore, the present invention provides a cylindrical outer member having a plurality of guide grooves spaced apart from each other at a predetermined interval and extending along the axial direction and connected to one transmission shaft, and an opening of the outer member. In a tripod type constant velocity joint having an inner member inserted into the inner space and connected to the other transmission shaft,
A plurality of trunnions bulging toward the guide groove;
A ring-shaped roller member that contacts the guide groove and is externally fitted to the trunnion;
A plurality of rolling elements interposed between the trunnion and the roller member so as to freely roll;
A pair of holding members for holding the rolling elements are mounted on both ends along the axial direction of the inner diameter portion of the roller member,
All of the rolling elements except for one are arranged in an annular shape along the inner diameter portion of the roller member, and then the last one is press-fitted into the interval between the annularly arranged rolling elements, Separation / dropping of rolling elements from the inner diameter is prevented,
A predetermined clearance is provided along the radial direction between the inner diameter portion of the roller member and the rolling element when adjacent rolling elements come into contact with each other in an annular shape due to the keystone effect.

  In this case, the radial clearance may be set to several μm to several tens μm.

  According to the present invention, after all the rolling elements except one are arranged in an annular shape along the inner diameter part of the roller member, the last one is press-fitted into the interval between the annularly arranged rolling elements. . In the state where all the rolling elements are loaded in the inner diameter part of the roller member, when the adjacent rolling elements are in an annular contact with each other by the Keystone effect, there is a gap between the inner diameter part of the roller member and the outer diameter of the rolling element. A predetermined clearance is provided along the radial direction.

  Therefore, according to the present invention, when the roller member is assembled to the trunnion, the circumferential direction between the adjacent rolling elements interposed between the roller member and the trunnion is caused by the clearance along the radial direction. As a result, the rolling motion of each rolling element is ensured, and the induced thrust force induced by the sliding friction can be suppressed.

  Further, in the present invention, after all the rolling elements except for one are arranged in an annular shape along the inner diameter portion of the roller member, the last one rolling element is press-fitted into the interval between the rolling elements. In addition, the space | interval of the two rolling elements of the both ends arranged in the said cyclic | annular form is set smaller than the outer diameter of the said rolling element.

  After all the rolling elements have been loaded into the inner diameter portion of the roller member in this way, the adjacent rolling elements are in annular contact with each other due to the keystone effect, and separation / dropping from the inner diameter portion of the roller member is prevented. In this case, a predetermined clearance is provided along the radial direction between the inner diameter portion of the roller member and the rolling element.

  Therefore, in the present invention, a constant velocity joint is provided so that the smooth rolling motion of each rolling element interposed between the roller member and the trunnion is ensured, and the induced thrust force induced due to the sliding friction is reduced. Can be assembled.

  According to the present invention, the following effects can be obtained.

  That is, all the rolling elements are loaded into the inner diameter part of the roller member by press-fitting the last one rolling element, and when the Keystone effect occurs, the radial direction is formed between the inner diameter part of the roller member and the rolling element. By providing this clearance, the smooth rolling motion of each rolling element is ensured, and the induced thrust force induced due to the slide friction can be suppressed. As a result, vibration generated by the induced thrust force can be suppressed.

  Preferred embodiments of a constant velocity joint and its assembling method according to the present invention will be described in detail below with reference to the accompanying drawings.

  In FIG. 1, reference numeral 10 denotes a tripod type constant velocity joint to which the method of assembling the constant velocity joint according to the embodiment of the present invention is applied. The constant velocity joint 10 is one end portion of a first shaft (not shown). Are basically connected to a cylindrical outer cup (outer member) 12 having an opening and an inner member 16 fixed to one end of the second shaft 14 and accommodated in the hole of the outer cup 12. Composed.

  As shown in FIG. 1, three guide grooves 18 a to 18 c are formed on the inner wall surface of the outer cup 12. The three guide grooves 18 a to 18 c extend along the axial direction and are spaced by 120 degrees around the axis. (However, the guide grooves 18b and 18c are not shown). The guide grooves 18a to 18c are composed of a ceiling portion 20 having a curved section, and sliding portions 22a and 22b that are opposed to each other on both sides of the ceiling portion 20 and have a circular arc shape. .

  A ring-shaped spider 24 is externally fitted to the second shaft 14, and three spiders 24 are swelled toward the guide grooves 18 a to 18 c on the outer peripheral surface of the spider 24 at intervals of 120 degrees around the axis. Trunnions 26a to 26c are integrally formed (however, trunnions 26b and 26c are not shown).

  A ring-shaped roller member 30 is fitted around the outer periphery of the trunnion 26a (26b, 26c) via a plurality of rolling elements 28. In addition, the rolling element 28 should just be a rolling bearing containing a needle, a roller, etc., for example.

  As shown in FIG. 2, the outer circumferential surface of the roller member 30 has an arcuate surface portion 32 formed corresponding to the cross-sectional shape of the sliding portions 22a and 22b so as to come into surface contact with the sliding portions 22a and 22b. And a first annular inclined surface portion 36a continuous from the arcuate surface portion 32 to the first surface 34, and a second annular inclined surface portion 36b continuous from the arcuate surface portion 32 to the second surface 38.

  An inner diameter portion (inner diameter surface) 40 having a constant diameter and functioning as a rolling surface of the rolling element 28 is formed on the inner periphery of the roller member 30, and an upper portion (one end portion) of the inner diameter portion 40. Is integrally provided with an annular first flange portion 42a formed so as to protrude in the radial inward direction by a predetermined length. On the other hand, an annular second flange portion 42b is formed integrally with a lower portion (the other end portion) of the inner diameter portion 40 opposite to the first flange portion 42a. It is done. Accordingly, the rolling elements 28 mounted in the inner diameter portion 40 of the roller member 30 are held from above and below by the first flange portion 42a and the second flange portion 42b formed at both ends of the inner diameter portion 40.

  As shown in FIG. 3, ring-shaped circlips 46 a and 46 b are respectively provided on one end portion and the other end portion along the axial direction of the inner diameter portion 40 of the roller member 30 via an annular groove 44. The rolling element 28 may be held between the pair of circlips 46a and 46b.

  For example, in the triport type constant velocity joint 10, a relative sliding motion occurs between the trunnion 26 a (26 b, 26 c) and the roller member 30 along the axial direction of the trunnion 26 a (26 b, 26 c). This is because it is necessary to provide holding members such as circlips 46a and 46b, for example, that restrict displacement along the axial direction of the rolling element 28 at both ends of the inner diameter portion 40 of the roller member 30.

  The relative sliding operation means that the trunnion 26a (26b, 26c) slides along the axial direction with respect to the roller member 30, or the roller member 30 moves with respect to the trunnion 26a (26b, 26c). It means sliding movement along the axial direction.

  As shown in FIG. 2, the boundary between the inner diameter portion 40 of the roller member 30 and the first and second flange portions 42 a and 42 b is a lubricant (for example, wax, grease) with respect to the wall surface of the inner diameter portion 40. Etc.) are formed, respectively, to form annular groove portions 52 that function as oil reservoirs.

  In the inner diameter portion 40 of the roller member 30, a plurality of rolling elements 28 are juxtaposed in parallel along the circumferential direction, and the rolling elements 28 are radially inward at both ends of the inner diameter portion 40, as will be described later. The first and second flange portions 42a and 42b projecting in the direction are held so as not to be separated and dropped from the inner diameter portion 40.

  The plurality of rolling elements 28 loaded along the inner diameter portion 40 of the roller member 30 have substantially the same diameter and are formed in substantially the same shape. The trunnions 26a (26b, 26c) are formed in a columnar shape having a constant outer diameter, as shown in FIG.

  The constant velocity joint 10 according to the present embodiment is basically configured as described above. Next, the function and effect will be described.

  Below, the assembly operation | work of the constant velocity joint 10 is demonstrated.

  Using a jig or the like (not shown), the entire number (predetermined number) of rolling elements 28 excluding the last one is loaded along the inner diameter portion 40 of the roller member 30. In addition, a lubricant (wax or grease or the like) 50 is previously applied to the wall surface of the inner diameter portion 40 of the roller member 30 to a predetermined thickness (corresponding to a clearance B described later). Therefore, between the inner diameter portion (inner diameter surface) 40 of the roller member 30 and the outer diameter of the plurality of rolling elements (excluding the last one) 28 loaded in the inner diameter portion 40, the lubricant 50 is provided. As a result, a radial clearance B is formed.

  As shown in FIG. 4, all the rolling elements 28 except one are loaded in an annular shape along the inner diameter portion 40 of the roller member 30, and the two rolling elements 28 at both ends arranged in the annular shape, An interval 54 in which the last one rolling element 28 a is inserted is generated between 28. In addition, the separation distance (distance between contact points) A1 of the interval 54 is set in advance so as to be smaller than the outer diameter A2 of the rolling element 28a (A1 <A2). Subsequently, the last one rolling element 28 a is subjected to a predetermined addition from the radial direction (lateral direction) of the roller member 30 within the interval 54 of the rolling elements 28 arranged along the inner diameter portion 40 of the roller member 30. Press-fitted by pressure.

  The last one of the press-fitted rolling elements 28a enters along the interval 54 between a pair of adjacent rolling elements 28 and passes through the interval 54 to contact the lubricant 50 applied to the inner diameter portion 40. By doing so, the loading of all the rolling elements 28, 28a is completed. All the rolling elements 28 and 28a are held along the axial direction between the first flange portion 42a and the second flange portion 42b or between the pair of circlips 46a and 46b. In addition, after the loading of all the rolling elements 28 and 28a into the inner diameter portion 40 of the roller member 30 is completed, the lubricant 50 is removed by heating to a predetermined temperature, for example.

  FIG. 6 shows a state in which all the rolling elements 28, 28a are held along the circumferential direction by the keystone effect, and an alternate long and short dash line in FIG. 6 indicates that all the rolling elements 28, adjacent by the keystone effect, The virtual circle D which connected the some contact point which 28a contacts is shown. In a state where all the adjacent rolling elements 28 and 28a are in annular contact with each other due to the Keystone effect, between the inner diameter portion (inner diameter surface) 40 of the roller member 30 and the outer diameter A2 of the rolling elements 28 and 28a, A predetermined clearance C is provided along the radial direction. The clearance C along the radial direction is set to, for example, several μmm to several tens of μmm.

  For example, when many types of vehicles are produced in Japan and overseas, by selecting and combining the types of roller members and rolling elements suitable for each vehicle type from a plurality of types having different dimensional shapes, etc. The best constant velocity joint is selected. In the process of selection and combination, it was found that it is preferable to set the clearance C along the radial direction to several μm to several tens of μmm by repeating simulation and test (experiment).

  If the clearance C along the radial direction is less than several μmm, smooth rolling motion of the rolling elements 28, 28a cannot be ensured. On the other hand, if the clearance C exceeds several tens of μmm, the keystone state is not achieved. Can't get. The “keystone state” refers to a state in which the rolling elements 28 and 28a are prevented from being separated and separated from the inner diameter portion 40 of the roller member 30 by the keystone effect, that is, a state in which the keystone effect can be generated. The rolling elements 28 and 28a are incorporated in the inner diameter portion 40 of the roller member 30.

  As described above, all the rolling elements 28, 28a loaded in the inner diameter portion 40 of the roller member 30 are prevented from being separated / dropped off from the inner diameter portion 40 by the occurrence of the keystone effect.

  The outer diameter A2 of the rolling element 28 and the inner diameter of the inner diameter part 40 of the roller member 30 are such that the keystone effect is obtained when all the rolling elements 28 and 28a are arranged in an annular shape along the inner diameter part 40 of the roller member 30. It is assumed that a predetermined value is set in advance so as to occur.

  FIG. 7 shows a state in which the roller member 30 is mounted on the outer peripheral surface of the trunnion 26a (26b, 26c) after all the rolling elements 28, 28a are loaded in the inner diameter portion 40 of the roller member 30. In this case, the adjacent rolling elements interposed between the roller member 30 and the trunnion 26a (26b, 26c) due to the radial clearance C provided when the rolling elements 28, 28a are assembled. 28 and 28a will be in a non-contact state, and the clearance E between contact points along the circumferential direction of adjacent rolling elements 28 and 28a will be formed.

  Therefore, due to the radial clearance C provided when the rolling elements 28 and 28a are assembled, the adjacent rolling elements 28 and 28a interposed between the roller member 30 and the trunnion 26a (26b and 26c) are connected to each other. By forming the clearance E between the contact points along the circumferential direction between the rolling elements, smooth rolling motion of each of the rolling elements 28, 28a is secured, and the induced thrust force induced by the sliding friction is suppressed. be able to. As a result, vibration generated by the induced thrust force can be suppressed.

  The “induced thrust force” refers to the relationship between the roller member 30 and the guide grooves 18a (18b, 18c) when a predetermined operating angle (the angle at which the first shaft and the second shaft 14 intersect) is loaded. A frequency analysis of the relationship between the sliding friction (force) generated between the two and the rotation angle of the joint, and the size of the rotating three-dimensional component is measured.

  As shown in FIG. 5, in the state where the lubricant 50 is not applied to the inner diameter portion 40 of the roller member 30 (the clearance B in FIG. 4 is zero), the last one rolling element 28 a is used as the rolling element 28. When the keystone effect is generated (see FIG. 6), the radial distance between the inner diameter portion (inner diameter surface) 40 of the roller member 30 and the outer diameter A2 of the rolling elements 28 and 28a is aligned. The outer diameter A2 of the rolling element 28 and the inner diameter of the inner diameter portion 40 of the roller member 30 may be set to predetermined values so that the predetermined clearance C is provided.

It is a partial expanded longitudinal cross-sectional view along the direction orthogonal to the axis line of the constant velocity joint to which the assembly method of the constant velocity joint which concerns on embodiment of this invention was applied. It is a longitudinal cross-sectional view of the roller member which comprises the constant velocity joint shown in FIG. It is a partial expanded longitudinal cross-sectional view along the direction orthogonal to the axis line of the constant velocity joint which concerns on other embodiment of this invention. FIG. 5 is a partially enlarged explanatory view showing a state in which the last one rolling element is press-fitted into the interval between the rolling elements arranged along the inner diameter portion of the roller member to which the lubricant is applied. It is a partial expanded explanatory view which shows the state which press-fits the last one rolling element with respect to the space | interval of the rolling elements arranged along the internal diameter part of a roller member. It is a partial expanded explanatory view which shows the state by which all the rolling elements were hold | maintained along the circumferential direction by the keystone effect. FIG. 5 is a partially enlarged explanatory view showing a state where the roller members are mounted on a trunnion after all the rolling elements are loaded in the inner diameter portion of the roller members. In the constant velocity joint which concerns on a prior art, it is a cross-sectional view which shows the press injection method of the rolling element to the cylindrical internal peripheral surface of a roller.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10, 10a ... Constant velocity joint 12 ... Outer cup 16 ... Inner member 18a-18c ... Guide groove 26a-26c ... Trunnion 28, 28a ... Rolling member 30 ... Roller member 40 ... Inner diameter part 42a, 42b ... Flange part 44 ... Annular groove 46a 46b ... Circlip 50 ... Lubricant 54 ... Interval A1 ... Distance A2 ... Outer diameter B, C ... Clear D ... Virtual circle E ... Clear clearance between contact points

Claims (5)

A plurality of guide grooves that are spaced apart by a predetermined distance and extend along the axial direction are provided on the inner peripheral surface, and are inserted into a cylindrical outer member that is connected to one of the transmission shafts, and an inner space that is opened by the outer member. In a tripod type constant velocity joint having an inner member coupled to the other transmission shaft,
A plurality of trunnions bulging toward the guide groove;
A ring-shaped roller member that contacts the guide groove and is externally fitted to the trunnion;
A plurality of rolling elements interposed between the trunnion and the roller member so as to freely roll;
At both end portions along the axial direction of the inner diameter portion of the roller member, flange portions that protrude inward in the radial direction are respectively formed.
All of the rolling elements except for one are arranged in an annular shape along the inner diameter portion of the roller member, and then the last one is press-fitted into the interval between the annularly arranged rolling elements, Separation / dropping of rolling elements from the inner diameter is prevented,
A constant velocity joint in which a predetermined clearance is provided along the radial direction between the inner diameter portion of the roller member and the rolling element when adjacent rolling elements come into annular contact with each other due to the keystone effect. . A plurality of guide grooves that are spaced apart by a predetermined distance and extend along the axial direction are provided on the inner peripheral surface, and are inserted into a cylindrical outer member that is connected to one of the transmission shafts, and an inner space that is opened by the outer member. In a tripod type constant velocity joint having an inner member coupled to the other transmission shaft,
A plurality of trunnions bulging toward the guide groove;
A ring-shaped roller member that contacts the guide groove and is externally fitted to the trunnion;
A plurality of rolling elements interposed between the trunnion and the roller member so as to freely roll;
A pair of holding members that hold the rolling elements are attached to both ends along the axial direction of the inner diameter portion of the roller member,
All of the rolling elements except for one are arranged in an annular shape along the inner diameter portion of the roller member, and then the last one is press-fitted into the interval between the annularly arranged rolling elements, Separation / dropping of rolling elements from the inner diameter is prevented,
A constant velocity joint in which a predetermined clearance is provided along the radial direction between the inner diameter portion of the roller member and the rolling element when adjacent rolling elements come into annular contact with each other due to the keystone effect. . In the constant velocity joint according to claim 1 or 2,
The constant velocity joint according to claim 1, wherein the radial clearance is set to several μm to several tens of μmm. A plurality of guide grooves that are spaced apart by a predetermined distance and extend along the axial direction are provided on the inner peripheral surface and connected to one transmission shaft, and are connected to the other transmission shaft toward the guide groove. A plurality of trunnions that bulge out, a ring-shaped roller member that comes into contact with the guide groove and is fitted on the trunnion, and a plurality of rolling members that are rotatably mounted between the trunnion and the roller member. In the assembling method of the tripart type constant velocity joint having a moving body,
A step of arranging all the rolling elements except one in an annular shape along the inner diameter portion of the roller member;
A step in which an interval between two rolling elements at both ends arranged in an annular shape is set smaller than an outer diameter of the rolling element, and the last one rolling element is press-fitted into the interval between the rolling elements;
When the adjacent rolling elements come into annular contact with each other due to the keystone effect to prevent separation / dropping from the inner diameter part of the roller member, the radial direction is provided between the inner diameter part of the roller member and the rolling element. A predetermined clearance is provided,
A method of assembling a constant velocity joint, comprising: In the method of assembling the constant velocity joint according to claim 4,
The method for assembling the constant velocity joint, wherein the radial clearance is set to several μm to several tens of μmm.

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