WO2007023802A1

WO2007023802A1 - Flexible boot for constant velocity universal joint

Info

Publication number: WO2007023802A1
Application number: PCT/JP2006/316392
Authority: WO
Inventors: Tomoshige Kobayashi; Teruaki Fujio; Masazumi Kobayashi
Original assignee: Ntn Corporation
Priority date: 2005-08-23
Filing date: 2006-08-22
Publication date: 2007-03-01

Abstract

A flexible boot for a constant velocity universal joint enabling the simplification of boot mounting operation and boot manufacturing steps. The flexible boot comprises a bellows having a tubular large diameter part fixed to the outer peripheral surface of an outer joint member, a tubular small diameter part fixed to the outer peripheral surface of a shaft, and a flexible part of U-shape in cross section connecting the large diameter part to the small diameter part and a metal cylindrical adapter for reinforcement vulcanized and integrated in the bellows starting at the large diameter part to the end part of the flexible part of the bellows. One end of the adapter is projected by a predetermined length along the outer periphery of the outer joint member, and the projected portion of the adapter is fixedly caulked onto the outer peripheral surface of the outer joint member.

Description

Specification

Flexible boots for constant velocity universal joints

Technical field

[0001] The present invention relates to a flexible boot for a constant velocity universal joint suitable for a propeller shaft.

Background art

[0002] Flexible boots for constant velocity universal joints are designed to prevent leakage of grease sealed inside the joints and prevent foreign objects from entering the inside of the joints. , And fixed to the outer circumference of the shaft splined to the inner joint member. There are flexible boots that have a bellows-like bent part and those that have a U-shaped bent part.

[0003] A constant velocity universal joint for a propeller shaft has a considerably high rotational speed in the normal rotation range compared to a constant velocity universal joint for a drive shaft. For this reason, flexible boots used for constant velocity universal joints for propeller shafts are those that have a U-shaped bend that is difficult to rotate and expand.

FIG. 19 shows a conventional constant velocity universal joint for a propeller shaft. The constant velocity universal joint 11 has a large diameter fixed to the outer joint member 12a of the constant velocity universal joint 12 through a metal cylindrical reinforcing adapter 13 with the body made of a flexible material such as rubber. Part 11a, a small-diameter part l ib fixed to the shaft 12b of the constant velocity self-joint 12 by a boot band 15, and a bent part 11c having a U-shaped cross section connecting the large-diameter part 11a and the small-diameter part l ib . One end of the adapter 13 holds and grips the large-diameter portion 11a of the boot 11, and the other end is the end of the outer joint member 12a in order to ensure sealing and retaining strength against the outer joint member 12a. After being press-fitted into the outer peripheral surface via an O-ring 14, it is crimped and fixed by rolling caulking. The substantially U-shaped bent portion 11c of the boot 11 is inserted in a space between the inner peripheral surface of the adapter 13 and the outer peripheral surface of the shaft 12b, and when the joint rotates at an operating angle, Repeat bending and stretching operations.

[0005] As described above, this type of boot is difficult to rotate and expand, and has a U-shaped cross section. Since the expansion displacement of the curved portion l ie is regulated by the adapter 13, the rotational expansion resistance is excellent as compared with the bellows-like boot. However, the boot shown in Fig. 19 requires installation of the O-ring 14, press-fitting of the adapter 13, caulking work, and fouling treatment when attaching to the outer joint member 12a. It takes time and skill. Also in the manufacturing process, machining of the O-ring groove on the outer peripheral surface of the outer joint member and dimensional tolerance management during adapter press-fitting were extremely complicated.

Therefore, as shown in FIG. 20, a slightly downsized adapter 13a is vulcanized and integrated with the boot to eliminate the need for the O-ring and O-ring groove, and the large-diameter portion id is connected to the outer joint member 12a by the boot band 16. A boot 11 that is fixed is proposed (Patent Document 1).

Patent Document 1: Japanese Patent Laid-Open No. 11-159538

Disclosure of the invention

Problems to be solved by the invention

[0007] Since the improved flexible boot is formed with the adapter 13a, the improved flexible boot has a rotational center position of the adapter 13a due to poor positioning of the adapter 13a in the vulcanization mold. The boot 11 or the center of rotation of the bellows may be slightly misaligned. Since the constant velocity universal joint for propeller shafts has a high speed in the normal rotation range, the boot 11 may swing around due to centrifugal force if a slight amount of deviation occurs during production. If the boot 11 swings around, it may cause vibration and noise, and if it is severe, the boot 11 may come off.

[0008] The present invention is to solve the problem, and an object of the present invention is to suppress swinging and boot disengagement of a boot having a vulcanized integrated adapter.

Means for solving the problem

[0009] The boot for a constant velocity universal joint of the present invention includes a torque transmission member accommodated between an outer joint member and an inner joint member, and a shaft connected to the inner joint member does not extend outside the joint. A flexible boot disposed between the outer periphery of the outer joint member and the outer periphery of the intermediate portion of the shaft of the constant velocity universal joint, and has a cylindrical large diameter fixed to the outer peripheral surface of the outer joint member A bellows comprising a cylindrical small-diameter portion fixed to the outer peripheral surface of the shaft, a bent portion having a U-shaped cross section connecting the large-diameter portion and the small-diameter portion, and the bellows A metal cylindrical reinforcing adapter vulcanized and integrated in the bellows from the large diameter portion of the rose to the end of the bent portion, and one end of the adapter from the large diameter portion of the bellows to the outer joint member It is characterized by projecting a predetermined length along the outer periphery of the outer periphery and fixing the projecting portion to the outer peripheral surface of the outer joint member.

[0010] The problem of boot vibration and boot disengagement with a conventional vulcanized integrated adapter is that the rotation center position (flexible part) of the boot is shifted from the rotation center position of the adapter, so This was caused by a balance. In the present invention, the adapter is protruded from the large diameter portion of the bellows, and the protruding portion is caulked and fixed to the outer peripheral surface of the outer joint member, thereby suppressing the swinging of the boot.

[0011] The protruding portion of the adapter may be caulked and fixed to the outer peripheral surface of the outer joint member together with the large diameter portion by a boot band attached to the outer periphery of the large diameter portion.

[0012] At this time, the protruding portion of the adapter may be completely exposed to the outside without covering the bellows material, but the protruding portion is extended from the large-diameter portion of the bellows from the viewpoint of eliminating the need for a fouling treatment. It can be covered with a thin film of existing bellows.

[0013] The protruding portion of the adapter may be formed continuously in the circumferential direction of the adapter, but may be formed intermittently at a plurality of locations in the circumferential direction of the adapter. Considering that the force acting on the adapter is not so great, the intermittent formation of the protruding portions at a plurality of locations in the circumferential direction of the adapter contributes to weight reduction and material saving of the boot.

[0014] Preferably, a concave portion for caulking and fixing the protruding portion of the adapter is desirably formed on the outer peripheral surface of the outer joint member to ensure the fixing. This concave portion can be easily formed because it does not require strict processing accuracy like an O-ring press-fitting groove.

The invention's effect

[0015] As described above, in the present invention, one end of the adapter is protruded by a predetermined length of the large-diameter portion of the bellows, and this protruding portion is fixed by crimping to the outer peripheral surface of the outer joint member. Even if the center positions of the two are slightly deviated, the center positions of both are accurately aligned by caulking and fixing the adapter to the outer joint member. As a result, it is possible to solve problems such as vibrations and noises associated with the swirling that the boot does not swing even if the constant velocity universal joint rotates at a high speed, and further, the boot coming off. The boot of the present invention Since no o-ring is used between the outer joint member and the outer joint member, it is compared with conventional boots that do not require complicated and cumbersome operations such as o-ring groove processing on the outer joint member and dimensional tolerance management when the adapter is press-fitted. Thus, it can be easily manufactured at low cost.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a state in which a flexible boot 101 according to a first embodiment of the present invention is attached to a fixed type constant velocity universal joint 102 for a propeller shaft. The constant velocity universal joint 102 has an outer joint member 102a in which a plurality of curved guide grooves 102a1 are formed in the axial direction on the inner peripheral surface, and a plurality of curved guide grooves 102bl in the axial direction on the outer peripheral surface. The ball 102c and the ball 102c arranged on the ball track formed by the cooperation of the guide groove 102al of the inner joint member 102b and the outer joint member 102a and the guide groove 102bl of the inner joint member 102b are divided into two equal operating angles. A retainer 102d for holding in-plane, and a shaft 102e fitted with a selection (or spline) to the inner joint member 102b are provided.

[0017] The boot 101 includes a flexible bellows 101a made of chloroprene rubber (CR rubber) and the like, and a metal cylindrical reinforcing adapter 101b. The bellows 101a includes a cylindrical large-diameter portion lOlal, a cylindrical small-diameter portion 101a2, a step portion 101a3 continuously extending from the large-diameter portion lOlal to the inner diameter side, and a step portion 101a3 extending in the axial direction continuously. A cylindrical portion 101a4 and a bent portion 101a5 that is bent in a substantially U shape and continues to the small diameter portion 101a2. A metal cylindrical reinforcing adapter 10 lb is embedded in the region including the cylindrical portion 101a4 from the large diameter portion lOlal by vulcanization integration. The configuration of the small diameter portion 101a2 is the same as that of the conventional boot 11 shown in FIGS. 19 and 20, and is fixed to the shaft 102e by a boot band 115.

[0018] As described above, the adapter 101b is embedded in the bellows 101a by vulcanization integration. One end of the adapter 101b extends from the large-diameter portion lOlal of the boot 101 along the outer peripheral surface of the outer joint member 102a. As shown in FIG. On the outer peripheral surface of the outer joint member 102a, a recess 102a2 having a smooth arc bottom is formed at a position corresponding to the protruding portion lOlbl. After the large-diameter portion lOlal of the boot 101 is fitted to the outer joint member 102a, the protruding portion lOlbl of the adapter 101b is pressed in the direction of the arrow, and the recess 102a as shown in FIG. Clamped to 2 Since the protruding part lOlbl may sprout as it is, a thin film 101a6 of bellows material that is separately protected by painting, etc., or extended from the large diameter part lOlal of the bellows 101a as shown in Fig. 2B. Cover with. Such a thin film 101a6 can be easily formed by setting the inner surface clearance of the vulcanization mold without providing a separate step when the adapter 101b is vulcanized and integrated. Since the thin film 101a6 is very thin, it is of course not an obstacle to the caulking and fixing of the adapter 101b.

Specifically, the protruding portion lOlbl of the adapter 101b can be formed along the entire circumference in the circumferential direction as shown in FIG. In this case, it is advisable to make incisions 104 at several places in the circumferential direction (six places in the illustrated example). The depth of the notch 104 is appropriately formed as long as it does not reach the large diameter portion lOlal of the bellows 101a. Even if the notch 104 is formed, the large diameter portion 1 Olal of the bellows 101a is tightly fixed to the outer peripheral surface of the outer joint member 102a, so that the sealing performance of the boot 101 is not affected at all.

[0020] The protruding portion lOlbl of the adapter 101b is formed along the entire circumference, and is formed intermittently at equal intervals (90 ° intervals) at four locations in the circumferential direction as shown in FIGS. 4 (A) and 4 (B). May be. Since the adapter 101 b does not have such a large force, even if it is formed intermittently in this way, a sufficient fixing force can be obtained. Note that, as described above, there is no influence on the sealing performance of the force boot 101 in which a large notch 105 is formed between the protruding portions lOlbl.

[0021] Next, a second embodiment of the present invention will be described. FIG. 5 shows a state where the flexible boot 201 according to the second embodiment of the present invention is attached to a fixed type constant velocity universal joint 202 for a propeller shaft. The constant velocity universal joint 202 has an outer joint member 202a in which a plurality of curved guide grooves 202a1 are formed in the axial direction on the inner peripheral surface, and a plurality of curved guide grooves 202bl in the axial direction on the outer peripheral surface. The ball 202c and the ball 202c arranged on the ball track formed by the cooperation of the guide groove 202a1 of the inner joint member 202b and the outer joint member 202a and the guide groove 202b1 of the inner joint member 202b are operated at an angle of 2 A retainer 202d that is held in an equally divided plane, and a shaft 202e that is seleted (or spline) fitted to the inner joint member 202b are provided.

[0022] The boot 201 includes a flexible bellows 201a made of chloroprene rubber (CR rubber) or the like, gold It is composed of a cylindrical reinforcing adapter 201b. The bellows 201a includes a cylindrical large-diameter portion 201al, a cylindrical small-diameter portion 201a2, a step portion 201a3 continuously extending from the large-diameter portion 201al toward the inner diameter side, and a step portion 201a3 continuously extending in the axial direction. A cylindrical portion 201a4 and a bent portion 201a5 which is bent into a substantially U-shape and is continuous with the small diameter portion 201a2. A metal cylindrical reinforcing adapter 20 lb is embedded in a region including the large diameter portion 201al to the tubular portion 201a4 by vulcanization integration. The configuration of the small diameter portion 201a2 is the same as that of the conventional boot 11 shown in FIGS. 19 and 20, and is fixed to the shaft 202e by a boot band 215.

[0023] As described above, the adapter 201b is a force embedded in the bellows 201a by vulcanization integration, one end of which protrudes by a predetermined length toward the large-diameter portion 201al of the boot 201 than the conventional one in FIG. I am letting. On the outer peripheral surface of the outer joint member 202a, a recess 202a2 having a flat bottom is formed at a position corresponding to the protruding portion 201bl. Then, after fitting the large-diameter portion 201al of the boot 201 into the recess 202a2 of the outer joint member 202a, the protruding portion 201bl of the adapter 201b is pressed against the recess 202a2 by the tightening force of the boot band 204 as shown in FIG. Secure with caulking. The length of the protruding portion 201bl may be a length that completely overlaps the concave portion 202a2, or may be a length that protrudes to the middle of the concave portion 202a2 as shown in FIG. In short, it is sufficient that the protrusion length is such that the boot band 4 can be caulked and fixed to the recess 2a2.

[0024] The protruding portion 201bl of the adapter 201b may be formed along the entire circumference in the circumferential direction. In this case, in order to improve the attachment to the outer joint member 202a and the caulking deformation, It is recommended to make incisions at several places in the direction. Further, as shown in FIGS. 7A and 7B, the protruding portions 201bl of the adapter 201b may be intermittently formed at several places in the circumferential direction (three places in the illustrated example). Since a large force does not act on the adapter 201b, a sufficient fixing force can be obtained even if it is formed intermittently in this way.

[0025] Next, a third embodiment of the present invention will be described. FIG. 8 shows a state where the flexible boot 301 according to the third embodiment of the present invention is attached to a fixed type constant velocity universal joint 302 for a propeller shaft. The constant velocity universal joint 302 includes an outer joint member 302a in which a plurality of curved guide grooves 302 al are formed in the axial direction on the inner peripheral surface, and an inner side in which a plurality of curved guide grooves 302 bl are formed in the axial direction on the outer peripheral surface. With the guide member 302a 1 of the joint member 302b and the outer joint member 302a A ball 302c disposed on a ball track formed in cooperation with the guide groove 302b 1 of the inner joint member 302b, a retainer 302d for holding the ball 302c in the bisection plane of the operating angle, and an inner joint A shaft 302 e fitted with a selection (or spline) to the member 302 b is provided.

[0026] The boot 301 includes a flexible bellows 301a made of chloroprene rubber (CR rubber) or the like, and a metal cylindrical reinforcing adapter 301b. The bellows 301a includes a cylindrical large-diameter portion 301al, a cylindrical small-diameter portion 301a2, a step portion 301a3 that continuously extends from the large-diameter portion 301al to the inner diameter side, and a step portion 301a3 that continuously extends in the axial direction. A cylindrical portion 301a4 and a bent portion 301a5 which is bent into a substantially U-shape and is continuous with the small diameter portion 301a2. A metal cylindrical reinforcing adapter 30 lb is embedded in the region including the large diameter portion 301al to the cylindrical portion 301a4 by vulcanization integration. The configuration of the small diameter portion 301a2 is the same as that of the conventional boot 11 shown in FIGS. 19 and 20, and is fixed to the shaft 302e by a boot band 315.

[0027] As described above, the adapter 301b is embedded in the bellows 301a by vulcanization integration. As shown in FIG. 9A, one end of the adapter 301b extending into the cylindrical portion la4 of the bellows 301a is It is turned 180 ° toward the outer joint member 302a and protrudes to the inner peripheral surface of the outer joint member 302a with a predetermined length. As a result, the open end of the outer joint member 302a is sandwiched between the adapter main body 301b2 in the large diameter portion 301al and the protruding portion 301bl. In the illustrated example, the bellows 301a may be structured such that only the force protruding portion 301bl that covers the entire adapter 301b including the protruding portion 301bl protrudes from the bellows 301a and is exposed inside the joint. In this case, the protrusion 301bl directly contacts the inner peripheral surface of the outer joint member 302a.

[0028] The large diameter portion 301al of the bellows 301a is fitted to the outer peripheral surface of the outer joint member 302a. A concave portion 302a2 having a flat bottom is formed on the outer peripheral surface of the outer joint member 302a, and the large diameter portion 301al of the bellows 301a is fitted into the concave portion. A boot band 304 is attached to the outer periphery of the large diameter portion 301al, and the large diameter portion 301al is pressure-bonded to the recess 302a2. In FIG. 9A, the adapter main body 301b2 is not protruded to the position where it is sandwiched between the boot band 304 and the recess 302a2. You can fix it by crimping to 02a2!

[0029] The protrusion 301bl of the adapter 301b may be formed integrally with the adapter main body 301b2 as shown in FIG. 9A, but the protrusions 301b and l are formed separately as the adapter 301b of FIG. 9B. In addition, the main body 301b'2 may be welded. Since the adapter 301b only needs to be able to simply hold the outer joint member 302a, the material of the adapter 301b can be made of steel plate, fiber reinforced plastic, or the like. The adapter 301b may be continuously formed along the entire circumference as shown in FIG. 10, but may be intermittently formed at a plurality of locations in the circumferential direction (for example, 2 to 3 locations). Also good.

[0030] Next, fourth to seventh embodiments of the present invention will be described. FIGS. 11 to 18 show constant velocity universal joints according to fourth to seventh embodiments of the present invention, which are barfield type constant velocity universal joints (one type of fixed constant velocity universal joints incorporated in a propeller shaft of an automobile). BJ) is applied as an example.

[0031] According to the flexible boots of the fourth to seventh embodiments, the outer peripheral surface of the large diameter portion is inscribed in an overlapped manner with the inner peripheral surface of the outer end of the boot mounting side of the outer member, and the large diameter portion and outer The conventional O-ring seal structure can be abolished because it is fixed by caulking while sandwiching the opening end of the member on the boot mounting side. In addition, the number of parts can be reduced, and the cost of the product can be reduced. Furthermore, since the adapter can be made into a simple shape, it is possible to simplify the press-fitting and caulking work of the adapter, reduce the input material, and improve the workability.

The constant velocity universal joint of each embodiment shown in FIGS. 11 to 18 includes an outer ring 21 that is an outer member, an inner ring 22 that is an inner member, a plurality of balls 23 that transmit torque, and balls 23 The main component is a cage 24 that rotatably supports the cage 24.

[0033] The outer ring 21 is formed with a track groove 25 extending in the axial direction at equal circumferential positions on the spherical inner surface. In addition, the inner ring 22 has a track groove 26 extending in the axial direction at a circumferentially equidistant position on the spherical outer surface, and a shaft 27 is connected to the inner periphery thereof by spline fitting or the like so that torque can be transmitted. ing. The shaft 27 is prevented from coming off from the inner ring 22 by a retaining ring 28. The track groove 25 of the outer ring 21 and the track groove 26 of the inner ring 22 are paired to form a ball track, and one ball 23 is assembled to each ball track. It is crowded. The cage 24 is slidably interposed between the spherical inner surface of the outer ring 21 and the spherical outer surface of the inner ring 22, and each ball 23 is accommodated in a pocket of the cage 24 and is held at equal intervals in the circumferential direction.

The outer peripheral surface of the cage 24 is in spherical contact with the spherical inner surface of the outer ring 21, and the inner peripheral surface of the cage 24 is spherically engaged with the spherical outer surface of the inner ring 22. The center of the spherical inner surface of the outer ring 21 and the center of the spherical outer surface of the inner ring 22 coincide with the joint center. On the other hand, the center of the track groove 25 of the outer ring 21 and the center of the track groove 26 of the inner ring 22 are offset by an equal distance in the opposite direction to each other in the axial direction.

[0035] In this type of constant velocity universal joint, grease is enclosed as a lubricant, and the grease leaks to the outside, or foreign matter such as water and dust enters the inside of the joint from the outside. In order to prevent this, a sealing boot 29 is mounted between the outer ring 21 of the constant velocity universal joint and the shaft 27 extending from the inner ring 22.

[0036] The constant velocity universal joint for propeller shafts has a considerably higher rotation speed than the constant velocity universal joint for drive shafts. Therefore, as the boot 29 used for the constant velocity universal joint for the propeller shaft, one having a U-shaped bent portion which is difficult to rotate and expand is used.

A boot 29 according to the fourth embodiment shown in FIGS. 11 and 12 includes a boot main body 30 made of a flexible material such as rubber, and a metallic cylindrical adapter 31. The boot body 30 includes a large-diameter portion 30a fixed to the open end 21a of the outer ring 21 of the constant velocity universal joint, a small-diameter portion 30b fixed to the shaft 27 extending from the inner ring 22 of the constant-velocity self-joint, It consists of a bellows portion 30c having a U-shaped cross section provided between the large diameter portion 30a and the small diameter portion 30b. The adapter 31 includes an outer cylindrical portion 31a disposed on the outer peripheral surface of the open end 21a of the outer ring 21, an inner cylindrical portion 31b disposed on the inner peripheral surface of the large-diameter portion 30a, and the aforementioned outer cylindrical portion. The flange portion 31c is provided between 31a and the inner cylindrical portion 3 lb.

When assembling the boot 29 to this constant velocity universal joint, the outer peripheral surface of the large-diameter portion 30a of the boot 29 is inscribed in an overlapped state with the inner peripheral surface of the open end portion 21a of the outer ring 21. Then, the large-diameter portion 30a and the open end portion 21a of the outer ring 21 are fixed by caulking with the adapter 31 sandwiched therebetween. By this caulking and fixing, the large-diameter portion 30a and the open end portion 21a of the outer ring 21 are sandwiched between the outer cylindrical portion 31a and the inner cylindrical portion 31b of the adapter 31 in a superposed state. The adapter 31 and the open end 21a of the outer ring 21 and the adapter 31 and the large diameter portion 30a are simultaneously crimped and fixed.

[0039] Since the large-diameter portion 30a is pressed against the inner peripheral surface of the open end 21a of the outer ring 21 in this way, it functions as a seal structure that prevents leakage of grease and entry of foreign matter. The o-ring seal structure can be abolished. Further, by adopting a simple shape consisting of the outer cylindrical portion 31a, the inner cylindrical portion 31b and the flange portion 31c, the adapter 31 can simplify the press-fitting and caulking work of the adapter 31. Furthermore, it is not necessary to perform the assembly work of the adapter 31 and the large diameter portion 30a in a separate process.

[0040] If an annular concave groove 32 is formed on the outer peripheral surface of the opening end 21a of the outer ring 21, and the end of the outer cylindrical portion 31a of the adapter 31 is crimped so as to be fitted into the concave groove 32, Fixing by caulking becomes even stronger.

[0041] It should be noted that an annular engagement groove 33 is formed in the shaft 27 along the circumferential direction at a position spaced apart from the opening end 21a of the outer ring 21 by a predetermined amount. The small-diameter portion 30b of the boot 29 is externally fitted into the engagement groove 33, and the boot band 35 is fastened to the fitting groove 34 formed on the outer peripheral surface of the small-diameter portion 30b. It is fixed to.

The fifth embodiment shown in FIGS. 13 and 14 exemplifies a structure in which a boot mounting portion 42 by caulking is provided on the large diameter portion side of the adapter 41. In the fifth embodiment, the same parts as those in the fourth embodiment are denoted by the same reference numerals, and redundant description is omitted.

[0043] The boot mounting portion 42 of the adapter 41 in the fifth embodiment has a structure in which the large diameter portion 30a of the boot 29 is held by caulking the inner cylindrical portion 41b. As a result, an assembly in which the adapter 41 is assembled to the large-diameter portion 30a of the boot 29 can be obtained. In this way, a prepared assembly in which the adapter 41 is assembled in advance to the large-diameter portion 30a of the boot 29 is prepared, and then the adapter 41 is press-fitted into the open end 21a of the outer ring 21 and crimped in the subsequent process. The large-diameter portion 30a of the boot 29 can be assembled to the outer ring 21. In this case, the assembly work of the adapter 41 and the large-diameter part 30a must be carried out in a separate process, but the conventional O-ring is not required and the press-fitting and caulking work of the simple adapter 41 is simplified. Can be planned.

[0044] In the above description, the adapter 41 and the large diameter portion 30a of the boot 29 are assembled in advance by caulking. It is also possible to assemble the adapter 41 and the open end 21a of the outer ring 21 in advance by crimping, and then crimp and fix the large-diameter portion 30a of the boot 29 with the adapter 41.

The sixth embodiment shown in FIGS. 15 and 16 exemplifies a structure in which an annular concave groove 36 into which the large diameter portion 30a is fitted is formed on the inner peripheral surface of the opening end portion 21a of the outer ring 21. In the sixth embodiment, the same parts as those in the fourth and fifth embodiments are denoted by the same reference numerals, and a duplicate description is omitted.

In the sixth embodiment, the annular concave groove 36 into which the large diameter portion 30a is fitted is formed on the inner peripheral surface of the opening end portion 21a of the outer ring 21. As a result, the large-diameter portion 30a is fitted into the concave groove 36 formed in the inner peripheral surface of the opening end portion 21a of the outer ring 21, so that the function as the above-described seal structure can be more reliably exhibited. .

The seventh embodiment shown in FIGS. 17 and 18 exemplifies a structure in which the large-diameter side end of the adapter 51 is bent outward and a folded portion 52 is provided at the large-diameter side end. . In the seventh embodiment, the same parts as those in the fourth to sixth embodiments are denoted by the same reference numerals, and a duplicate description is omitted.

[0048] In the seventh embodiment, by providing the folded portion 52 formed by bending the end portion of the inner cylindrical portion 51b of the adapter 51 outward, it is possible to damage the large diameter portion 30a at the end face of the adapter 51. Can be prevented.

The embodiment of the present invention has been described above, but the boot of the present invention is not limited to the fixed type constant velocity universal joint of FIG. 1, but a sliding type constant velocity universal joint, a double offset type, a cross group type, a tri-board It can be similarly applied to other types of constant velocity universal joints such as molds. Of course, the present invention can be applied not only to a constant velocity universal joint for a propeller shaft but also to a constant velocity universal joint for a drive shaft.

Brief Description of Drawings

FIG. 1 is a cross-sectional view showing a state in which a boot according to a first embodiment of the present invention is attached to a constant velocity universal joint.

FIG. 2A is an enlarged cross-sectional view around the large diameter portion of FIG. 1 before caulking the adapter.

FIG. 2B is a cross-sectional view similar to FIG. 2A, in which the protruding portion of the adapter is covered with a thin film of bellows. [FIG. 3] (A) is a partially cutaway perspective view of a flexible boot, and (B) is a perspective view of only the adapter of the flexible boot.

FIG. 4A is a partially cutaway perspective view of a flexible boot according to another embodiment, and FIG. 4B is a perspective view of only the adapter of the flexible boot.

[5] Cross-sectional view showing a state in which the boot of the second embodiment of the present invention is attached to the constant velocity universal joint.

FIG. 6 is an enlarged sectional view of the bellows large diameter portion.

[FIG. 7] (A) is a partially cutaway perspective view of a flexible boot, and (B) is a perspective view of only the adapter of the flexible boot.

8] A sectional view showing a state in which the boot of the third embodiment of the present invention is attached to a fixed type constant velocity universal joint.

FIG. 9A is an enlarged cross-sectional view of the large diameter portion of the bellows.

FIG. 9B is an enlarged cross-sectional view of the bellows large diameter portion including a modification of the adapter.

[FIG. 10] (A) is a perspective view with a partially cutout flexible boot, and (B) is a perspective view of only the adapter of the flexible boot.

[11] FIG. 11 is a sectional view showing a state in which the boot is mounted on the constant velocity universal joint in the fourth embodiment of the present invention.

FIG. 12 is an enlarged cross-sectional view of the main part of FIG.

FIG. 13] A sectional view showing a state in which the boot is mounted on the constant velocity universal joint in the fifth embodiment of the present invention.

FIG. 14 is an enlarged cross-sectional view of a main part of FIG.

15] A sectional view showing a state in which the boot is mounted on the constant velocity universal joint in the sixth embodiment of the present invention.

FIG. 16 is an enlarged cross-sectional view of the main part of FIG.

FIG. 17 is a cross-sectional view showing a state in which the boot is mounted on the constant velocity universal joint in the seventh embodiment of the present invention.

FIG. 18 is an enlarged cross-sectional view of the main part of FIG.

[19] Cross-sectional view of a constant velocity universal joint equipped with a conventional flexible boot. FIG. 20 is a cross-sectional view of a constant velocity universal joint equipped with another conventional flexible boot.

Claims

The scope of the claims

[1] The outer joint portion of a constant velocity universal joint in which a torque transmission member is accommodated between the outer joint member and the inner joint member, and a shaft connected to the inner joint member extends outside the joint. A flexible boot disposed between the outer periphery of the material and the outer periphery of the intermediate portion of the shaft, the cylindrical large-diameter portion fixed to the outer peripheral surface of the outer joint member, and fixed to the outer peripheral surface of the shaft A bellows composed of a cylindrical small-diameter portion and a u-shaped bent portion connecting the large-diameter portion and the small-diameter portion, and from the large-diameter portion of the bellows to the end of the bent portion Therefore, a metal cylindrical reinforcing adapter vulcanized and integrated into the bellows is provided, and one end of the adapter is projected for a predetermined length along the outer periphery of the outer diameter joint member of the large diameter portion of the bellows, The protruding portion is fixed by crimping to the outer peripheral surface of the outer joint member. Flexible boots to that constant velocity universal joint.

[2] The protruding portion of the adapter is caulked and fixed to the outer peripheral surface of the outer joint member together with the large diameter portion by a boot band attached to the outer periphery of the large diameter portion. Item 2. A flexible boot for a constant velocity universal joint according to item 1.

3. The flexible boot for a constant velocity universal joint according to claim 1 or 2, wherein the protruding portion of the adapter is covered with a thin film of bellows material protruding from the large diameter portion of the bellows.

[4] The flexible boot for a constant velocity universal joint according to any one of claims 1 to 3, wherein the protruding portions of the adapter are intermittently formed at a plurality of locations in the circumferential direction of the adapter.

5. The flexible boot for a constant velocity universal joint according to any one of claims 1 to 4, wherein a concave portion for caulking and fixing the protruding portion of the adapter is formed on the outer peripheral surface of the outer joint member.

[6] A large-diameter portion that is fitted with a reinforcing ring to the opening end of the outer member of the constant velocity universal joint, a small-diameter portion that is attached to a shaft connected to the inner member of the constant-velocity universal joint, A substantially U-shaped bellows portion provided between the large-diameter portion and the small-diameter portion, the outer peripheral surface of the large-diameter portion is inscribed in an overlapped state with the inner peripheral surface of the opening end portion of the outer member, A constant velocity universal joint characterized by being fixed by caulking with the large-diameter portion and the open end of the outer member sandwiched by a reinforcing ring Flexible noble boots for hands.

7. The flexible boot for a constant velocity universal joint according to claim 6, wherein an annular concave groove into which the large diameter portion is fitted is formed on the inner peripheral surface of the opening end portion of the outer member.

8. The flexible boot for a constant velocity universal joint according to claim 6 or 7, wherein a boot mounting portion by caulking is provided on the large diameter portion side of the reinforcing ring.

[9] The flexible boot for a constant velocity universal joint according to [6] or [7], wherein the end portion on the large-diameter portion side of the reinforcing ring is bent outward and a folded portion is provided on the end portion on the large-diameter portion side. .

[10] A large-diameter portion fitted with a reinforcing ring to the opening end of the outer member of the constant velocity universal joint, a small-diameter portion attached to a shaft connected to the inner member of the constant-velocity universal joint, A method for assembling a flexible boot for a constant velocity universal joint provided with a substantially U-shaped bellows portion provided between a large diameter portion and a small diameter portion, wherein the outer peripheral surface of the large diameter portion is an outer member. A flexible boot for a constant velocity universal joint, wherein the reinforcing ring and the outer end of the outer ring, and the reinforcing ring and the large-diameter portion are caulked simultaneously. Assembly method.

[11] A large-diameter portion fitted with a reinforcing ring to the opening end of the outer member of the constant velocity universal joint, a small-diameter portion attached to a shaft connected to the inner member of the constant-velocity universal joint, A method for assembling a flexible boot for a constant velocity universal joint provided with a substantially U-shaped bellows portion provided between a large diameter portion and a small diameter portion, wherein the outer peripheral surface of the large diameter portion is an outer member. In contact with the inner peripheral surface of the opening end of the outer ring in a superposed state, and crimping one of the opening end of the reinforcing ring and the outer member or the difference between the reinforcing ring and the large diameter portion in advance. Assembly method for flexible boots for quick universal joints.