JP2011241922A - Outside joint member of constant motion universal joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an outside joint member of a constant motion universal joint which outside joint member compensates a reduction in the cross-sectional area of a spline (male spline) forming part on an end part to improve twist strength.SOLUTION: The outside joint member of the constant motion universal joint includes a mouth part 11 having a track groove formed on its inner diameter surface, and a hollow shaft part 12 extending from the mouth part 11. A solid member 20 short in size in axial direction is inserted in an end part of the hollow shaft part 12 opposite to the mouth part, where the solid member 20 connected integrally to the hollow shaft part 12 via an irregular fitting structure M is inserted. Axially extending projections 31 are formed on the outer diameter surface of the solid member 20. The solid member 20 is press fitted into the end part of the hollow shaft part 12 opposite to the mouse part, at which the solid member 20 extrudes and/or cuts part of the inner diameter surface 30 of the end part 12c opposite to the mouth part. As a result, a recesses 32 closely fitting to the projections 31 are formed along the axial direction on the inner diameter surface 30 of the end part 12c opposite to the mouth part. Hence the irregular fitting structure M is constructed, in which the projections 31 and the recesses 32 are closely fitted together in their entire areas at a fitting contact part 33.

Description

  The present invention relates to an outer joint member in a constant velocity universal joint used for a drive shaft (drive shaft).

  As an outer joint member of a constant velocity universal joint, there is one having a hollow stem as described in Patent Document 1. As shown in FIG. 14, the outer joint member includes a mouth portion 1 that accommodates an inner joint member, a ball, a cage (cage), and the like, and a stem (hollow stem) that extends integrally from the mouth portion 1 in the axial direction. 2 is provided.

  The mouse portion 1 includes a cup-shaped main body portion 1a, the main body portion 1a, and a short shaft portion 1b protruding from the bottom wall of the main body portion 1a. Long stem) 2 is joined. A male spline 3 is formed on the outer peripheral surface of the end of the hollow stem 2 on the side opposite to the mouse.

  In this case, the hollow stem 2 is formed by stepping the pipe material into a stepped shape by swaging or the like, and a joining method such as friction welding is applied to the end face 4 on the large diameter side to the end face 5 of the short shaft 1b. Are joined through. As described above, the purpose of using the hollow stem for the outer joint member of the constant velocity universal joint is to improve the torsional rigidity and the weight of the outer joint member with the longer axis.

  However, the shaft end where the male spline is formed is hollow. For this reason, it is inferior to fatigue strength etc. compared with a solid thing. For this reason, although it is not an outer joint member of a constant velocity universal joint, there is a hollow shaft in which padding is arranged on the inner diameter portion of the shaft in a state where torque can be transmitted to the shaft (Patent Document 2). With such a configuration, the proof stress can be increased without impairing the characteristics of the hollow shaft, and the fatigue strength is improved. This Patent Document 2 discloses the following method as an integration method of a hollow shaft and a solid separate member (internal fitting member).

  The first method is to insert an inner fitting member having a convex portion formed by knurling or the like on the outer diameter surface of the hollow inner diameter surface of the hollow shaft, and then caulking the outer diameter surface of the hollow shaft in the reduced diameter direction. In this method, these members are joined so as to bite.

  The second method is a method in which a spline-shaped convex portion is formed on the outer diameter surface of the inner fitting member or the inner diameter surface of the hollow shaft, and the spline-shaped convex portion is press-fitted to the other side. The third method is a method in which grooves are formed in advance on both members and the grooves are fitted to each other.

JP 2007-75824 A JP-A-2005-113986

  In the first method, since the concave and convex fitting such as serration fitting is not performed, the bonding force is poor, and when a large repetitive stress is applied or an excessive torque is applied, the bonding of this portion is easy. There is a risk of being released. That is, the function as a torque transmission member cannot be exhibited sufficiently.

  In the second method, for example, when the serrated convex portion is formed on the outer diameter surface of the inner fitting member, the serrated convex portion is in pressure contact with the inner diameter surface of the hollow shaft. Here, the press contact shape indicates a coupling form having a pressing force applied to the apex of the convex portion by pressing the serrated convex portion into the hollow inner surface. For this reason, with such a pressure contact force, the coupling force is weak as in the first method, and the function as a torque transmission member cannot be sufficiently exhibited.

  In the third method, it is necessary to form the uneven portions in advance on both sides, which increases the processing cost. In addition, it is necessary to match the phases of the splines when assembled, resulting in poor assembly workability.

  Therefore, the present invention has been proposed in view of the above-mentioned problems, and the object of the present invention is to compensate for the reduction in the cross-sectional area in the formation portion of the end spline portion (male spline) and torsional strength. An object of the present invention is to provide an outer joint member of a constant velocity universal joint capable of improving the above.

  The outer joint member of the constant velocity universal joint of the present invention includes a mouth portion in which a track groove is formed on the inner diameter surface, and a hollow shaft portion extending from the mouth portion, An outer joint member of a constant velocity universal joint in which a short solid member in the axial direction that is integrally connected via a concave-convex fitting structure is fitted, and a convex portion that extends in the axial direction on the outer diameter surface of the solid member The solid member is press-fitted into the end of the hollow shaft on the side of the anti-mouse part, and by this press-fitting, a part of the inner diameter surface of the end of the side of the anti-mouse part is pushed out and / or cut. The concave-convex fitting structure is formed in the inner diameter surface of the portion so as to closely fit the convex portion along the axial direction, and the entire fitting contact portion between the convex portion and the concave portion is in close contact.

  According to the outer joint member of the constant velocity universal joint of the present invention, when the solid member is press-fitted into the hollow shaft portion, the concave portion closely fitting to the convex portion can be formed along the axial direction in the hollow shaft portion. . And since the whole fitting contact site | part of a convex part and a recessed part is closely_contact | adhering, the clearance gap which produces backlash in radial direction and the circumferential direction is not formed in this fitting structure. For this reason, the hollow shaft portion and the solid member are integrated with a stable coupling force.

  A plurality of the convex portions are arranged at a predetermined pitch along the circumferential direction on the outer diameter surface of the solid member, and the diameter of the arc drawn by the apex of the convex portion is larger than the inner diameter of the hollow shaft portion on the side opposite to the mouse portion. It is preferable to increase the value. By setting in this way, when press-fitted, the convex portion can stably extrude and / or cut a part of the hollow shaft portion, and the adhesion of the fitting contact portion can be improved. .

  A male spline is formed on the outer diameter surface of the hollow shaft portion on the side opposite to the mouse portion, and the axial range of the concave-convex fitting structure can be a range from the spline end surface to the spline cut-up portion.

  A male spline is formed on the outer diameter surface of the hollow shaft portion on the side opposite to the mouse portion, and the male spline is formed on the inner diameter surface of the side gear into which the end portion on the anti-mouse portion side of the hollow shaft portion is fitted. A female spline to be fitted with the concave-convex fitting structure may be formed, and an axial range of the concave-convex fitting structure may include a range including all female splines and the cut-up portion of the male spline.

  The hollow shaft portion may have a non-fitting portion at a part between the inner diameter surface of the end portion on the side opposite to the mouse portion and the outer diameter surface of the solid member. A male spline is formed on the outer diameter surface of the mouth portion side end portion, and the male spline is fitted on the inner diameter surface of the side gear into which the anti-mouse portion end portion of the hollow shaft portion is fitted. And the non-fitting portion can be set to be outside the effective spline fitting range between the male spline and the female spline.

  The inner diameter surface of the end portion of the hollow shaft portion on the side opposite to the mouse is preferably an uncured surface before press-fitting. Thus, if the inner diameter surface of the hollow shaft portion on the side opposite to the mouth portion is an uncured surface before press-fitting, extrusion and / or cutting during press-fitting can be performed stably.

  The outer diameter surface of the hollow shaft portion may be subjected to thermosetting treatment before the solid member press-fitting.

  It is preferable to provide a guide portion for guiding the press-fitting at the press-fitting start end portion of the solid member. Moreover, you may make it provide the taper guide part which expands toward the opening side in the anti-mouse part side edge part opening part of the said hollow shaft part.

  It is preferable that the entire circumference of the outer end in the axial direction between the inner diameter surface of the hollow shaft portion on the side opposite to the mouse portion and the outer diameter surface of the solid member is closed with a seal member. Further, a concave seal application part may be provided at the outer end in the axial direction, and the seal member may be applied to the seal application part.

  Further, the hollow shaft portion may be subjected to cutting of the outer diameter surface, spline molding, and thermosetting treatment after the solid member is internally fitted. Spline molding may be rolling molding or press molding. You may harden the whole anti-mouse part side edge part of a hollow shaft part.

The outer joint member is preferably used for an outer joint member of a constant velocity universal joint used for a drive shaft of an automobile.

  In the outer joint member of the constant velocity universal joint of the present invention, the hollow shaft portion and the solid member are integrated with a stable coupling force, so that a large repetitive stress is applied to the shaft, or excessive torque is applied. Even in the case where there is a problem, there is little possibility that the coupling of the concave-convex fitting structure is released, and the function as a torque transmission member can be stably exhibited. Moreover, by providing a torque transmitting portion in the hollow portion of the hollow shaft portion, it is possible to compensate for the reduction in the cross-sectional area of the end portion on the side opposite to the mouse due to the hollow shape, and to improve the strength against torsion. . That is, it is possible to provide an outer joint member of a constant velocity universal joint that can improve torsional strength inexpensively and easily by simply press-fitting a solid member into the hollow shaft portion.

  Moreover, it is not necessary to form a spline portion or the like in the member (hollow shaft portion) in which the concave portion is formed, which is excellent in productivity and does not require phase alignment between the splines, thereby improving the assemblability. At the same time, damage to the tooth surface during press-fitting can be avoided, and a stable fitting state can be maintained.

  The diameter of the arc drawn by the apex of the convex part is set to be larger than the inner diameter of the end of the hollow shaft on the side opposite to the mouse, and the adhesion of the mating contact area is improved to maintain a more stable mating state. it can.

  The axial range of the concave-convex fitting structure can be the range from the spline end face of the male spline to the raised part, or the range including all female splines formed by press-fitting and the raised part of the male spline. It is possible to relieve stress at a portion where the stress is concentrated (spline cut-up portion).

  Pressure input to the hollow shaft portion of the solid member by providing a non-fitting part in a part between the inner diameter surface of the end portion of the hollow shaft on the side opposite to the mouse and the outer diameter surface of the solid member ( (Insertion force) can be reduced, and the assemblability is excellent. Further, the non-fitting portion can be set to be outside the spline effective fitting range between the male spline formed on the outer diameter surface of the hollow shaft and the female spline formed on the side gear to be fitted. As a result, the torque transmission function of the spline fitting portion is not impaired.

  If the inner diameter surface of the hollow shaft portion on the side opposite to the mouse portion is an uncured surface before press-fitting, extrusion and / or cutting at the time of press-fitting can be performed stably, and assembly workability can be improved. Can do.

  Even if the outer diameter surface of the hollow shaft portion is subjected to thermosetting treatment before the solid member is press-fitted, the outer diameter surface is cut with respect to the hollow shaft portion after the solid member is fitted. Processing, spline molding, and thermosetting treatment may be performed, and the degree of freedom of the processing process of the outer joint member is great, and the productivity is excellent. As a spline, it can be easily formed using an existing forming apparatus such as roll forming or press forming, and the cost can be reduced.

  By providing a guide portion for guiding the press-fitting at the press-fitting start end portion of the solid member, it is possible to improve the press-fitting property. Further, by providing a taper guide portion that expands toward the opening side at the end portion of the hollow shaft portion on the side opposite to the mouth portion, the shaft of the hollow shaft portion and the solid member at the start of press-fitting of the solid member is provided. Centering can be performed with high accuracy.

  If the entire circumference of the axially outer end between the inner diameter surface of the hollow shaft portion on the side opposite to the mouse and the outer diameter surface of the solid member is closed with a seal member, the side gear is spline-fitted and differential When incorporated in the apparatus, the penetration of grease (lubricant) or the like into the hollow shaft portion can be prevented. Further, in the case where the concave seal application part is provided, the application amount of the seal member is stabilized, and the sealing function can be improved.

  Thus, the outer joint member of the present invention can improve torsional strength and the like, and is optimal for a drive shaft of an automobile.

It is sectional drawing of the outer joint member of the 1st constant velocity universal joint of this invention. The solid member inserted by the said outer joint member is shown, (a) is a front view, (b) is a side view. It is a half-cut sectional view which shows the state before inserting a solid member in the said outer joint member. It is an expanded sectional view of the state where the solid member was fitted in the hollow shaft part. It is sectional drawing of the state in which the side gear is mounted | worn with the said outer joint member. It is an A1 direction arrow line view of FIG. It is a principal part expanded sectional view of FIG. It is principal part sectional drawing of the outer joint member of the 2nd constant velocity universal joint of this invention. It is an A2 direction arrow line view of FIG. It is principal part sectional drawing of the outer joint member of the 3rd constant velocity universal joint of this invention. It is a half cut sectional view of the press fit state using the 1st modification of a solid member. It is a half cut sectional view of the press fit state using the 2nd modification of a solid member. It is principal part sectional drawing of the outer joint member of the 4th constant velocity universal joint of this invention. It is a half cut sectional view of the outside joint member of the conventional constant velocity universal joint.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  The outer joint member of the constant velocity universal joint of the embodiment shown in FIG. 1 includes a mouth portion 11 and a hollow stem (hollow shaft portion) 12 that extends integrally from the mouth portion in the axial direction. This outer joint member is an outer joint member of a tripod type constant velocity universal joint. For this reason, track grooves are formed on the inner diameter surface of the mouth portion 11 and arranged at a pitch of 120 ° along the circumferential direction.

  The mouse portion 11 includes a bowl-shaped main body portion 11a, a main body portion 11a, and a short shaft portion 11b protruding from the bottom wall of the main body portion 11a. The short shaft portion 11b has a hollow shaft portion ( Hollow long stem) 12 is joined.

  The hollow shaft portion 12 has a large-diameter portion 12a, a medium-diameter portion 12b, and a small-diameter portion 12c, and a first taper portion 12d is provided between the large-diameter portion 12a and the medium-diameter portion 12b. A second taper portion 12e is provided between the portion 12b and the small diameter portion 12c. Further, the inner diameter of the medium diameter portion 12b and the inner diameter of the small diameter portion 12c are set to be the same, and the inner diameter of the large diameter portion 12a is set to be larger than the inner diameters of the medium diameter portion 12b and the small diameter portion 12c. And the male spline 13 is formed in the outer diameter surface of the small diameter part 12c, ie, an anti-mouse part side edge part. A circumferential groove 19 is provided at the end of the male spline 13.

  Further, the short shaft portion 11b has a base portion 15 on the bottom wall side of the main body portion 11a and a bottomed short cylindrical portion 16 provided continuously from the base portion 15, and an end surface of the short shaft portion 11b, that is, an existence surface. The end face 17 of the bottom short cylinder part 16 is joined to the end face 18 on the mouse part side of the large diameter part 12a through joining means such as a friction welding method. Here, the friction welding method is a joining method in which members to be joined (for example, metal or resin) are rubbed together at high speed, and the members are softened by the frictional heat generated at the same time, and at the same time, pressure is applied to join them.

  The hollow shaft portion 12 is integrally formed from the same steel pipe. For example, the hollow shaft portion 12 is subjected to plastic working such as swaging for striking and reducing the diameter at a high speed while rotating the raw pipe around the axis. Molded.

  An axially short solid member 20 that is integrally connected via an uneven fitting structure M is fitted into a small diameter portion (end portion on the side opposite to the mouse) 12c having a male spline 13 formed on the outer peripheral surface. . As shown in FIG. 4, the concave-convex fitting structure M includes, for example, a convex portion 31 extending in the axial direction and a concave portion 32 formed on the inner diameter surface 30 of the end portion 12 c of the hollow shaft portion 12. The entire fitting contact portion 33 between the 20 convex portions 31 and the concave portion 32 fitted to the convex portion 31 is in close contact. That is, the convex part 31 and the concave part 32 fitted to this are tight-fitted over the entire circumference.

  In this case, each convex portion 31 has a triangular shape (mountain shape) having a convex round-shaped apex in the cross section, and is in the range H from the fitting contact portion (recessed portion fitting portion) 33, and has a mountain shape in the cross section. It is the range from the mid-abdomen to the summit.

  By the way, the said convex part 31 forms the spline 35 which consists of the convex part 35a and recessed part 35b along an axial direction, as shown to Fig.2 (a) (b). And the convex part 35a of the spline 35 is hardened, and this convex part 35a becomes the convex part 31 of the concave-convex fitting structure M. As this thermosetting treatment, various heat treatments such as induction hardening and carburizing and quenching can be employed. Here, induction hardening is a hardening method that applies the principle of heating a conductive object by placing Joule heat in a coil through which high-frequency current flows, and generating Joule heat by electromagnetic induction. is there. The carburizing and quenching is a method in which carbon is infiltrated / diffused from the surface of the low carbon material and then quenched.

  On the inner diameter surface 30 side of the end portion 12c of the hollow shaft portion 12, an uncured portion (unbaked state) where no thermosetting treatment is performed. The hardness difference between the convex portion 31 and the uncured portion of the end 12c of the hollow shaft portion 12 is, for example, 20 points or more in HRC. More specifically, the hardness of the surface of the convex portion 31 is set to about 50 HRC to 65 HRC, and the hardness of the uncured portion is set to about 10 HRC to about 30 HRC.

  At this time, the intermediate portion in the protruding direction of the convex portion 31 corresponds to the position of the concave portion forming surface (in this case, the inner diameter surface 30 of the end portion 12c) before the concave portion is formed. That is, as shown in FIGS. 3 and 4, the inner diameter d of the inner diameter surface 30 of the end portion 12 c is connected to the maximum outer diameter of the convex portion 31, that is, the top portion of the convex portion 31 that is the convex portion 35 a of the spline 35. It is set smaller than the diameter dimension (circumferential circle diameter) D of the circle and larger than the diameter dimension D1 of the circle connecting the valley bottoms between the convex portions (the bottoms of the concave portions 35b of the splines 35). That is, D1 <d <D. For this reason, at least the convex part 31 of the solid member 20 is press-fitted into the inner diameter surface 30 of the end part 12 c of the hollow shaft part 12 from the vertex to the intermediate part in the protruding direction.

  The spline 35 can be formed by various processing methods such as rolling processing, cutting processing, press processing, and drawing processing, which are known and publicly known means. Moreover, various heat processing, such as induction hardening and carburizing hardening, can be employ | adopted as a thermosetting process. The press-fitting start end surface 31a of the convex portion 31 formed by forming the spline 35 is a flat surface orthogonal to the axial direction of the shaft portion.

  Next, a method for integrating the hollow shaft portion 12 and the solid member 20 will be described. First, the shaft center of the hollow shaft portion 12 and the shaft center of the solid member 20 are combined. In this state, the solid member 20 is inserted (press-fitted) into the hollow shaft portion 12. At this time, the diameter dimension d of the inner diameter surface 30, the diameter dimension D of the convex portion 31, and the diameter dimension D1 of the concave portion 35b of the spline 35 are as described above, and the hardness of the convex portion 31 is the inner diameter surface. Since the hardness of 30 is 20 points or more, if the solid member 20 is press-fitted into the end 12c of the hollow shaft portion 12, the convex portion 31 bites into the inner diameter surface 30, and the convex portion 31 becomes The concave portion 32 into which the convex portion 31 is fitted is formed along the axial direction.

  As shown in FIG. 1, this press-fitting is performed until the end surface (outer end surface) 20 a of the solid member 20 coincides with the end surface 25 of the hollow shaft portion 12. As a result, as shown in FIG. 4, the entire fitting contact portion 33 between the convex portion 31 of the solid member 20 and the concave portion 32 fitted therein is in close contact. That is, the shape of the convex portion 31 is transferred to the mating concave portion forming surface (in this case, the inner diameter surface 30 of the hollow shaft portion 12). At this time, as the convex portion 31 bites into the inner diameter surface 30, the end portion 12 c of the hollow shaft portion 12 is slightly expanded in diameter, allowing the convex portion 31 to move in the axial direction. If the movement stops, the end 12c is reduced in diameter to return to the original diameter. In other words, when the convex portion 31 is press-fitted, the end portion 12c is elastically deformed in the radial direction, and a preload corresponding to this elastic deformation is applied to the tooth surface of the convex portion 31 (surface of the concave portion fitting portion). For this reason, the concave / convex fitting structure M in which the entire concave portion fitting portion of the convex portion 31 is in close contact with the corresponding concave portion 32 can be reliably formed. That is, the spline (male spline) 35 on the solid member 20 side forms a female spline 36 (see FIG. 4) that is in close contact with the male spline 35 on the inner diameter surface 30 of the end 12c.

  In addition, if the solid member 20 is press-fitted, a protruding portion is formed. Here, the protruding portion is the material of the capacity of the concave portion 32 into which the convex portion 31 is fitted (fitted), and is extruded from the formed concave portion 32 and cut to form the concave portion 32. It is comprised from what was extruded, what was extruded, and what was cut.

  By the way, the press-fitting of the solid member 20 into the hollow shaft portion 12 may be after drawing. The processing sequence thereafter (after press-fitting and after drawing) is as follows: outer diameter turning → spline molding → heat treatment (thermosetting). Further, the press-fitting of the solid member 20 into the hollow shaft portion 12 may be performed after the outer surface of the hollow shaft portion 12 is cut and spline-formed. The subsequent processing sequence is a heat treatment (thermosetting treatment).

  The spline molding is the spline 13 of the end portion 12c on the side opposite to the mouth of the hollow shaft portion 12, and the molding is the same as the spline for forming the convex portion 31 of the solid member 20, the rolling process, the cutting process, It can be formed by various processing methods such as press working. Moreover, various heat processing, such as induction hardening and carburizing hardening, can be employ | adopted as a thermosetting process. The part to be cured in the thermosetting process may be only the outer surface of the end portion 12c on the anti-mouse portion side of the hollow shaft portion 12, or the entire thickness of the end portion 12c of the hollow shaft portion 12. Moreover, you may perform a thermosetting process over the full length of the hollow shaft part 12. FIG. In this case as well, only the outer surface or the entire thickness may be used.

  As shown in FIG. 5, the outer joint member configured in this manner is attached to a side gear 50 of a differential device (not shown) used in an automobile. That is, the side gear 50 includes a cylindrical main body portion 50a having a female spline 54 formed on its inner diameter surface, and a flange portion 50b extending in the outer diameter direction from the anti-mouse portion of the cylindrical main body portion. A plurality of teeth 51 are provided along the circumferential direction on the outer end surface of the flange portion 50b. By inserting the end portion 12 c of the hollow shaft portion 12 into the axial hole 53 of the side gear 50, the male spline 13 at the end portion 12 c of the hollow shaft portion 12 is fitted into the female spline 54 of the side gear 50.

  By the way, the differential apparatus generally includes a differential case having an input ring gear, a pinion gear pivotally supported in the differential case, and the side gear attached to the output shaft and meshing with the pinion gear. The pinion gear can revolve simultaneously with the rotation of the ring gear. In the straight traveling state, the rotation is transmitted to the ring gear, and the pinion gear revolves. Since the resistance applied to the left and right tires is the same, the rotation of the pinion gear is transmitted to the side gear as it is, and the rotation at the same speed is transmitted to the left and right drive shafts. However, when turning a curve, the moving distance of the inner tire is shorter than the outer side, and the resistance is increased. Then, the side gear rotates the pinion gear, and the pinion gear also rotates while revolving. Thereby, a rotation difference is automatically given to the left and right tires.

  Further, as described above, the circumferential groove 19 is provided in the end portion 12c on the anti-mouse portion side, and a retaining ring 55 is attached to the circumferential groove 19, and this retaining ring 55 is connected to the axial hole 53 of the side gear 50. Engages with an engaging portion 56 formed on the inner diameter surface.

  By the way, as shown in FIG. 5, in the state where the male spline 13 of the end 12c of the hollow shaft portion 12 is fitted to the female spline 54 of the side gear 50, the end surface (outer end surface) 20a of the solid member 20, that is, The end surface 25 of the hollow shaft portion 12 substantially coincides with the opening end of the shaft center hole 53 of the side gear 50, and the end surface (inner end surface) 20 b of the solid member 20 reaches the medium diameter portion 12 b of the hollow shaft portion 12. . For this reason, the inner end edge in the axial direction of the concave-convex fitting structure M is located slightly on the inner side in the axial direction from the cut-up portion 59 of the male spline 13. That is, as shown in FIG. 7, the range of the concave-convex fitting structure M can be a range including the rounded-up portion 59 of the male spline 13 from the end surface (outer end surface) 20 a of the solid member 20.

  In the present invention, if the solid member 20 is press-fitted into the hollow shaft portion 12, the concave portion 32 that closely fits to the convex portion 31 can be formed in the hollow shaft portion 12 along the axial direction. In addition, since the entire fitting contact portion 33 between the convex portion 31 and the concave portion 32 is in close contact with the concave-convex fitting structure M, there is a gap in which looseness occurs in the radial direction and the circumferential direction in the fitting structure M. Not formed. For this reason, since the hollow shaft portion 12 and the solid member 20 are integrated with a stable coupling force, a large repetitive stress is applied to the hollow shaft portion 12 or an excessive torque is applied. However, there is little possibility that the coupling of the concave-convex fitting structure M is released, and the function as a torque transmission member can be stably exhibited. Moreover, by providing a torque transmitting portion in the hollow portion of the hollow shaft portion 12, it is possible to compensate for the reduction in the cross-sectional area of the anti-mouse portion side end portion (anti-mouse portion side end portion) 12c due to the hollow shape. The strength against twisting can be improved. That is, it is possible to provide an outer joint member that can easily improve the torsional strength at low cost simply by press-fitting the solid member 20 into the hollow shaft portion 12.

  Moreover, it is not necessary to form a spline portion or the like on the member (hollow shaft portion) in which the concave portion 32 is formed, which is excellent in productivity and does not require phase alignment between the splines, thereby improving the assemblability. In addition, damage to the tooth surface during press-fitting can be avoided, and a stable fitting state can be maintained.

  Since the diameter of the arc drawn by the apex of the convex portion 31 is set larger than the inner diameter of the end portion 12c on the anti-mouse portion side of the hollow shaft portion 12, it is possible to improve the adhesion of the fitting contact portion 33, A more stable fitting state can be maintained.

  The range of the concave-convex fitting structure M can be set to a range including the cut-up portion 59 of the male spline 13, and stress relaxation at a portion where the torsional stress is concentrated (spline-cut-up portion) can be achieved. In addition, as in the embodiment, if the inner diameter surface 30 of the end portion 12c on the anti-mouse portion side of the hollow shaft portion 12 is an uncured surface before press-fitting, extrusion and / or cutting at the time of press-fitting can be performed stably. As a result, the assembly workability can be improved.

  Next, in FIGS. 8 and 9, the axial length A of the solid member 20 is set shorter than the axial length A of the solid member 20 shown in FIG. That is, the outer end surface 20 a of the solid member 20 corresponds to the circumferential groove 19, and the inner end surface 20 b of the solid member 20 corresponds to the raised portion 59 of the male spline 13. 5 and FIG. 8, the axial length A of the solid member 20 and the axial length B of the concave-convex fitting structure M are substantially the same length.

  For this reason, the range of the uneven fitting structure M is a range from the spline end surface 60 of the spline fitting portion of the hollow shaft portion 12 and the side gear 50 to the raised portion 59 of the male spline 13, that is, a spline effective fitting portion. By setting in this way, the length of the solid member 20 in the axial direction can be set short, the weight of the entire outer joint member can be reduced, and a torque transmission member is provided in the hollow portion of the hollow shaft portion 12. be able to. Further, since the axial length of the solid member 20 is set to be short, the press-fitting range (axial length) of the solid member 20 with respect to the hollow shaft portion 12 can be shortened, and the pressure input can be reduced. Workability can be improved.

  Next, in FIG. 10, a large-diameter portion 61 is provided in the inner diameter surface opening of the anti-mouse portion side end portion 12 c of the hollow shaft portion 12, whereby the anti-mouse portion-side end portion 12 c of the hollow shaft portion 12 is provided. A non-fitting portion 62 is formed between the inner diameter surface and the outer diameter surface of the solid member 20. That is, when the inner diameter of the large-diameter portion 61 is d ′ and the other inner diameter of the end portion 12c of the hollow shaft portion 12 is d, d <d ′, and the non-fitting portion 62 is a gap dimension. c, and the inner diameter d ′ dimension is set larger than the diameter dimension D (see FIGS. 3 and 4) of the circle connecting the vertices of the convex portions 31 of the solid member 20. The axial length A of the solid member 20 is longer than the axial length B in the range of the concave-convex fitting structure M, and A> B.

  For this reason, also in FIG. 10, a torque transmission member can be provided in the hollow part of the hollow shaft part 12, and the press-fitting range (with respect to the hollow shaft part 12 of the solid member 20 by having the non-fitting part 62 ( (Length in the axial direction) can be shortened, pressure input can be reduced, and assembling workability can be improved.

  The outer joint member shown in FIG. 11 is provided with a guide portion 65 for guiding the press-fitting at the press-fitting start end portion of the solid member 20. In this case, a small diameter shaft portion 66 having an outer diameter smaller than the inner diameter of the anti-mouse portion side end portion 12c of the hollow shaft portion 12 is provided at the press-fitting start end portion of the solid member 20, and the small diameter shaft portion 66 is provided. Therefore, the guide portion 65 is used. That is, when the outer diameter dimension of the small-diameter shaft portion 66 is D2, and the inner diameter dimension of the anti-mouse portion side end portion 12c is d, D2 <d. This difference is such that the core member 20 is not misaligned when the solid member 20 is press-fitted and can be smoothly press-fitted. Specifically, a gap dimension formed between the outer diameter surface of the small diameter shaft portion 66 and the inner diameter surface of the anti-mouse portion side end portion 12c is set to about 0.01 mm to 0.2 mm in the shaft portion diameter dimension. can do.

  In this way, by providing the guide portion 65 for guiding the press-fitting at the press-fitting start end portion of the solid member 20, the press-fit property can be improved.

  Next, the outer joint member shown in FIG. 12 is provided with a taper guide portion 70 that expands toward the opening side at the opening portion on the side opposite to the mouth of the hollow shaft portion 12. For this reason, at the start of press-fitting, the end surface 31 a on the press-fitting start side of the convex portion 31 of the solid member 20 comes into contact with the taper guide portion 70. Therefore, if it pushes into the hollow shaft part 12 of the solid member 20 from this state, it will be guided by the taper guide part 70, and while the axial center of the solid member 20 and the axial center of the hollow shaft part 12 will correspond, The actual member 20 is press-fitted.

  Thus, by providing the taper guide part 70 which expands toward the opening side at the opening part on the anti-mouse part side of the hollow shaft part 12, the hollow shaft part 12 at the start of press-fitting of the solid member 20 and Axial alignment with the solid member 20 can be performed with high accuracy.

  Next, the outer joint member shown in FIG. 13 seals the entire circumference of the outer end in the axial direction between the inner diameter surface 30 of the end portion 12c on the anti-mouse portion side of the hollow shaft portion 12 and the outer diameter surface of the solid member 20. It is closed with a member 75. That is, after the solid member 20 is press-fitted into the end portion 12 c of the hollow shaft portion 12, the sealing agent constituting the seal member 75 is applied to the end surface of the hollow shaft portion 12 on the side opposite to the mouse portion of the hollow shaft portion 12. It coat | covers so that the axial direction outer end of the internal diameter surface 30 of 12c and the outer diameter surface of the solid member 20 may be covered. As the sealing agent, silicon-based liquid packing or the like can be used.

  In this case, as shown in FIG. 10, the large-diameter portion 61 is provided in the inner diameter surface opening of the anti-mouse portion side end portion 12 c of the hollow shaft portion 12, whereby the anti-mouse portion-side end portion of the hollow shaft portion 12 is provided. A non-fitting portion 62 between the inner diameter surface of 12c and the outer diameter surface of the solid member 20 is formed. For this reason, this non-fitting part 62 comprises the concave seal application part (seal agent reservoir part) 76 provided in an axial direction outer end, and can apply a seal member to this seal application part 76.

  As shown in FIG. 13, if the sealing member 75 is used, the intrusion of grease (lubricant) or the like into the hollow shaft portion 12 can be prevented. In particular, in the case where the concave seal application part 76 is provided, the application amount of the seal member 75 is stabilized, and the sealing function can be improved.

  The outer joint member of the present invention can improve the torsional strength and the like, and as shown in FIGS. 5, 8, 10 and the like, a side gear 50 is attached to the end 12c of the hollow shaft portion 12, and the automobile Ideal for drive shafts.

  By the way, in the said embodiment, although it was for tripod type sliding constant velocity universal joints as an outer joint member, as another embodiment, even for double offset type sliding constant velocity universal joints, Furthermore, it may be for a fixed constant velocity universal joint of a bar field type or an undercut free type.

  As described above, the embodiments of the present invention have been described. However, the present invention is not limited to the above-described embodiments, and various modifications are possible. However, various shapes such as other trapezoidal shapes, semicircular shapes, semielliptical shapes, rectangular shapes, etc. can be adopted, and the area, number, circumferential arrangement pitch, etc. of the convex portions 31 can be arbitrarily changed. . That is, it is not necessary to form the spline 35, and the convex portion (convex tooth) 35a of the spline 35 to be the convex portion 31 of the concave-convex fitting structure M, and it may be a key or a curved wave. It may form a mating surface of the mold. The point is that the convex portion 31 disposed along the axial direction can be press-fitted into the mating side, and the concave portion 32 can be formed on the mating side with the convex portion 31 so as to closely fit the convex portion 31. The entire fitting contact portion 33 between the portion 31 and the concave portion 32 fitted thereto may be in close contact.

  Since only the press-fitting start end portion of the convex portion 31 only needs to be harder than the portion where the concave portion 32 is formed, it is not necessary to increase the overall hardness of the convex portion 31. Moreover, in the said embodiment, in the uneven | corrugated fitting structure M, as shown in FIG. 4, although the clearance gap 38 is formed between the convex parts 31 and 31 adjacent to the circumferential direction, the convex part 31 whole bites in and a clearance gap is formed. 38 may be eliminated. In addition, as a hardness difference between the convex portion 31 side and the concave portion forming surface side formed on the convex portion 31 (inner diameter surface 30 side of the hollow shaft portion 12), it is preferable to be 20 points or more in HRC, If the convex part 31 can be press-fitted, it may be less than 20 points.

  Although the end surface (press-fit start end) of the convex portion 31 is a surface orthogonal to the axial direction in the embodiment, it may be inclined at a predetermined angle with respect to the axial direction. In this case, it may be inclined from the inner diameter side toward the outer diameter side toward the anti-convex portion side or inclined toward the convex portion side.

  Furthermore, you may provide the small recessed part arrange | positioned in the internal diameter surface 30 with a predetermined pitch along the circumferential direction. The small recess needs to be smaller than the volume of the recess 32. Thus, by providing a small recessed part, the press-fit property of the convex part 31 can be aimed at. That is, by providing the small concave portion, the capacity of the protruding portion formed when the convex portion 31 is press-fitted can be reduced, and the press-fit resistance can be reduced. Various shapes such as a semi-elliptical shape and a rectangular shape can be adopted as the shape of the small concave portion, and the number can be arbitrarily set.

  As shown in FIG. 12, when the taper guide portion 70 is formed, the taper angle is within a range in which the hollow shaft portion 12 and the solid member 20 can be aligned with each other at the start of press-fitting of the solid member 20. Various changes can be made. Moreover, when forming the taper guide part 70, in the said embodiment, what formed the small diameter axial part 66 in the solid member 20 was used, However, Such a small diameter axial part 66 may not be formed. .

  Further, the outer dimensions, outer shape, and the like of the hollow shaft portion 12 are not limited to those illustrated in the drawings, and can be variously changed according to the portion to be used. Further, the hollow shaft portion 12 may be formed by joining a plurality of members.

11 Mouse part 12 Hollow shaft part 12c Anti-mouse part side end (small diameter part)
13 male spline 20 solid member 31 convex portion 32 concave portion 33 fitting contact portion 50 side gear 54 female spline 56 engaging portion 59 raised portion 62 non-fitting portion 65 guide portion 70 taper guide portion 75 seal member 76 seal application portion M Uneven fitting structure

Claims (17)

Axial direction including a mouth portion having a track groove formed on the inner diameter surface and a hollow shaft portion extending from the mouth portion, and is integrally connected to an end portion of the hollow shaft portion on the side opposite to the mouse via an uneven fitting structure An outer joint member of a constant velocity universal joint in which a short solid member is fitted,
Protrusions extending in the axial direction are provided on the outer diameter surface of the solid member, and the solid member is press-fitted into the end portion of the hollow shaft portion on the side opposite to the mouth portion. Is formed on the inner diameter surface of the end portion on the anti-mouse portion side, and a concave portion that closely fits the convex portion is formed along the axial direction, and the entire fitting contact portion between the convex portion and the concave portion is in close contact with each other. An outer joint member of a constant velocity universal joint, wherein the uneven fitting structure is configured.   A plurality of the convex portions are arranged at a predetermined pitch along the circumferential direction on the outer diameter surface of the solid member, and the diameter of the arc drawn by the apex of the convex portion is larger than the inner diameter of the hollow shaft portion on the side opposite to the mouse portion. The outer joint member of the constant velocity universal joint according to claim 1, wherein the outer joint member is also made larger.   A male spline is formed on the outer diameter surface of the hollow shaft portion on the side opposite to the mouth portion, and the axial range of the concave-convex fitting structure is a range from the spline end surface to the spline cut-up portion. The outer joint member of the constant velocity universal joint according to claim 1 or 2.   A male spline is formed on the outer diameter surface of the hollow shaft portion on the side opposite to the mouse portion, and the male spline is formed on the inner diameter surface of the side gear into which the end portion on the anti-mouse portion side of the hollow shaft portion is fitted. A female spline is formed, and an axial range of the concave-convex fitting structure is a range including all female splines and a cut-up portion of the male spline. The outer joint member of the constant velocity universal joint described in 1.   The non-fitting part is provided in a part between the inner diameter surface of the anti-mouse portion side end of the hollow shaft portion and the outer diameter surface of the solid member. The outer joint member of the constant velocity universal joint.   A male spline is formed on the outer diameter surface of the hollow shaft portion on the side opposite to the mouse portion, and the male spline is formed on the inner diameter surface of the side gear into which the end portion on the anti-mouse portion side of the hollow shaft portion is fitted. 6. The constant velocity universal joint according to claim 5, wherein a female spline is formed, and the non-fitting portion is outside a spline effective fitting range between the male spline and the female spline. Joint member.   The constant velocity universal joint according to any one of claims 1 to 6, wherein an inner diameter surface of the hollow shaft portion on the side opposite to the mouse portion is an uncured surface before press-fitting. Outside joint member.   The constant velocity according to any one of claims 1 to 7, wherein the outer surface of the hollow shaft portion is subjected to a thermosetting treatment formed before press-fitting a solid member. The outer joint member of the universal joint.   The outer joint member of the constant velocity universal joint according to any one of claims 1 to 8, wherein a guide portion for guiding press-fitting is provided at a press-fitting start end portion of the solid member.   The taper guide part which expands toward the opening side was provided in the anti-mouse part side edge part opening part of the said hollow shaft part, The one of any one of Claims 1-9 characterized by the above-mentioned. Outer joint member of quick universal joint   The whole circumference of the outer end in the axial direction between the inner diameter surface of the hollow mouse portion on the side opposite to the mouse portion and the outer diameter surface of the solid member is closed with a seal member. Item 11. The outer joint member of the constant velocity universal joint according to any one of Items 10.   The outer joint member of a constant velocity universal joint according to claim 11, wherein a concave seal application portion is provided at the outer end in the axial direction, and the seal member is applied to the seal application portion.   The hollow shaft portion is subjected to cutting of the outer diameter surface, spline molding, and thermosetting treatment after the solid member is internally fitted. 4. An outer joint member of the constant velocity universal joint according to item.   The outer joint member of the constant velocity universal joint according to claim 13, wherein the spline molding is rolling molding.   14. The outer joint member of a constant velocity universal joint according to claim 13, wherein the spline molding is press molding.   The outer joint member of the constant velocity universal joint according to any one of claims 13 to 15, wherein the entire end portion on the side opposite to the mouth portion of the hollow shaft portion is hardened.   The outer joint member of a constant velocity universal joint according to any one of claims 1 to 16, wherein the outer joint member is used for a drive shaft of an automobile.

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