JP4762790B2 - Fitting assembly body - Google Patents

Description

  The present invention relates to a joint assembly body in which a protective cover is attached to a drive shaft or the like used for power transmission of an automobile or the like.

  For example, drive shafts used for power transmission of automobiles, etc., are mainly composed of a sliding type constant velocity universal joint, an intermediate shaft, and a fixed type constant velocity universal joint, and between each constant velocity universal joint and the intermediate shaft. A bellows-like boot (hereinafter referred to as a boot) is attached to.

  The outer periphery of the drive shaft is covered with a protective cover made of elastomer (a material such as synthetic rubber or synthetic plastic) for the purpose of preventing damage or contamination when attaching to a vehicle body, particularly when attaching a knuckle or the like. It has been broken. There is a joint assembly body in which the drive shaft is covered with a protective cover.

  FIG. 4 shows a conventional joint assembly (cross-sectional view). In all the following figures, the wheel side (left side in each figure) is the outboard side, and the vehicle center side (right side in each figure) is the inboard side.

  The joint assembly JA4 includes an intermediate shaft 53 and a fixed type constant velocity universal joint 51 and a sliding type constant velocity universal joint 52, a fixed type constant velocity universal joint 51, and a sliding type constant velocity universal joint 52 connected to both ends of the intermediate shaft 53. The drive shaft comprising the boots 56 and 57 attached to the respective outer joint members 54 and 55 is covered with an elastomer protective cover 50.

Since the protective cover 50 is formed in a cylindrical shape and has tapered (inclined surface) -shaped reduced diameter portions 50a and 50b at both ends, this allows the knuckle N to be attached to the vehicle when the drive shaft is assembled. As indicated by the hatched arrows, the workability when mounting by moving from the inboard side to the outboard side is improved, and the outer joint of each of the fixed type constant velocity universal joint 51 and the sliding type constant velocity universal joint 52 is improved. The members 54 and 55 can be attached with one touch, and the protective cover 50 can be prevented from falling off.
JP 2005-256938 A

  Now, in the conventional joint assembly body JA4 as shown in FIG. 4, although there is an effect as described above, with such a structure, the position of the protective cover 50 relative to the drive shaft is not determined, Since the attachment state of the protective cover 50 is not stable, there is a problem that play occurs.

  As a cause of the above, the both ends of the protective cover 50 are provided with tapered diameter-reduced portions 50a and 50b in order to improve the workability when the knuckle N is attached. Then, the protective cover 50 is not fixed at a fixed position of the drive shaft, and the attachment state of the protective cover 50 is not stable.

  Accordingly, an object of the present invention is to determine the mounting position of the protective cover in the joint assembly body, stabilize the mounting state of the protective cover, and prevent rattling.

The joint assembly body of the present invention for solving the above-mentioned problems is that a pair of constant velocity universal joints are respectively attached to both ends of the intermediate shaft, and between the outer joint member of each of these constant velocity universal joints and the intermediate shaft, respectively. In a joint assembly body equipped with a boot and provided with a protective cover that covers at least the boot, the inner peripheral surface of the end portion of the constant velocity universal joint of the protective cover is formed by uneven fitting with a mating member facing the inner peripheral surface. One of the pair of constant velocity universal joints is a sliding type constant velocity universal joint, and the sliding type constant velocity universal joint side has a large diameter on the outer peripheral surface of the intermediate shaft. In addition, a step portion having a small diameter on the opposite side is provided, and a step portion that engages with the step portion of the intermediate shaft is formed on the inner peripheral surface of the protective cover .

When the joint assembly has the structure as described above, the engaging portion provided on the inner peripheral surface of the end portion of the constant velocity universal joint of the protective cover is unevenly fitted to the mating member facing the inner peripheral surface. Thus, since the position of the protective cover is restricted in the axial direction, the protective cover is fixed at a fixed position of the drive shaft. Further, if one of the pair of constant velocity universal joints constituting the joint assembly is a sliding type constant velocity universal joint, the sliding type constant velocity universal joint side has a large diameter on the outer peripheral surface of the intermediate shaft, and A step with a small diameter on the opposite side is provided, and a step that engages with a step on the intermediate shaft is formed on the inner peripheral surface of the protective cover. Omission can be prevented.

Next, the locking portion of the protective cover is used as a protrusion, and this protrusion is inserted into a protective cover positioning groove (hereinafter referred to as a groove) formed on the outer peripheral surface of the outer joint member of the sliding type constant velocity universal joint. (Claim 2). For this reason, the mounting position of the protective cover with respect to the drive shaft is determined on the sliding type constant velocity universal joint side. Further , of the pair of constant velocity universal joints, the other constant velocity universal joint is a fixed type constant velocity universal joint, and the engaging portion of the protective cover is a projection, and this projection is an outer joint member of the fixed type constant velocity universal joint. It was made to fit in the trough part of the boot | wearing mounted | worn with (Claim 3 ). For this reason, the mounting position of the protective cover with respect to the drive shaft is determined on the fixed type constant velocity universal joint side.

  When attaching the protective cover to the drive shaft, when determining the mounting position on the sliding type constant velocity universal joint side, the reason why the outer joint member of the sliding type constant velocity universal joint is provided with a groove is as follows. It is.

  If the locking part of the protective cover is a protrusion that fits into the valley of the boot that is attached to the outer joint member of the sliding type constant velocity universal joint, the boot will also be axially moved by plunging the sliding type constant velocity universal joint. This is because it becomes difficult to extend and contract and to lock the protrusion to the valley of the boot.

  In addition, the protective cover is provided with a locking portion by concave-convex fitting with a mating member facing the inner peripheral surface on the inner peripheral surface of the constant velocity universal joint side end. One constant velocity universal joint side of the pair of constant velocity universal joints may be separated from the other constant velocity universal joint side to form separate bodies (claim 5). For this reason, the protective cover can be adapted to a long intermediate shaft.

  According to the joint assembly body of the present invention, since the protective cover is fixed at a fixed position of the drive shaft, the mounting state of the protective cover is stable and it is difficult for rattling to occur. It can be efficiently prevented from falling off.

  Further, in the joint assembly of the present invention, when one of the pair of constant velocity universal joints constituting the joint assembly is a sliding type constant velocity universal joint, the sliding type constant velocity is formed on the outer peripheral surface of the intermediate shaft. Sliding by providing a stepped part with a large diameter on the universal joint side and a small diameter on the opposite side, and forming a stepped part that engages with the stepped part of the intermediate shaft on the inner peripheral surface of the protective cover Since the separation of the constant velocity universal joint is prevented and the protective cover is restrained in the axial direction, the mounting state of the protective cover is more stable and it is difficult to drop off when the vehicle body is assembled.

  Furthermore, the protective cover is separated at one constant velocity universal joint side and the other constant velocity universal joint side of the pair of constant velocity universal joints, and is provided as a separate body, thereby protecting the shape according to the shape of the constant velocity universal joint. Covers can be created and costs can be reduced.

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

  FIG. 1 shows a first embodiment (cross-sectional view) of the present invention. The joint assembly body JA1 includes an intermediate shaft 1, a fixed type constant velocity universal joint 2 and a sliding type constant velocity universal joint 3, which are connected to both ends thereof, the fixed type constant velocity universal joint 2, and the sliding type constant velocity universal. A drive shaft including boots 6 and 7 attached to the respective outer joint members 4 and 5 of the joint 3 constitutes a main portion, and the outer periphery of the drive shaft is covered with an elastomer protective cover 8.

  The constant velocity universal joint on one side (inboard side) of the joint assembly JA1 is a sliding type constant velocity universal joint 3 (tripod type). The sliding type constant velocity universal joint 3 includes a main part composed of an outer joint member 5 and an inner joint member described later. Rotational torque from a differential (not shown) is transmitted to the outer joint member 5 via a roller 19 fitted in a track groove 5a formed on the inner peripheral surface of the outer joint member 5 so as to extend in the axial direction. Then, rotational torque is sequentially transmitted to the inner joint member and the intermediate shaft 1. The outer joint member 5 is composed of an outer cylindrical portion 20 having an opening surface on one side and a shaft portion 21, and a boot mounting concave groove 22 is formed on the outer peripheral surface of the outer cylindrical portion 20 and the outer peripheral surface of the intermediate shaft 1. 23 is formed, and a concave groove 24 into which the protective cover 8 is fitted is formed on the outer peripheral surface of the outer cylinder portion 20 on the inboard side from the concave groove 22 for mounting the boot. The boot mounting concave grooves 22 and 23 are fitted with the large diameter portion and the small diameter portion of the boot 7, respectively, and the outer periphery thereof is fixed by caulking with metal bands 25 and 26. The inner joint member is composed of a trunnion 28 in which three journals 27 having a roller 19 rotatably attached to the other end are projected in the radial direction, and one shaft end of the shaft 1 is inserted into the shaft hole of the trunnion 28. They are connected by spline fitting. The other shaft end of the intermediate shaft 1 is connected to a fixed type constant velocity universal joint 2 described later.

  The other constant velocity universal joint (outboard side) of the joint assembly body JA1 is a fixed type constant velocity universal joint 2. In the fixed type constant velocity universal joint 2, the rotational torque from the intermediate shaft 1 is transmitted to a joint inner ring 12 described later, and further transmitted to the outer joint member 4 through a torque transmission ball 9. The outer joint member 4 includes a cup-shaped mouth portion 10 having a closed end (outboard side) and an opening at the other end (inboard side) and a shaft-shaped stem portion 11. A plurality of track grooves 10a are formed in the portion. A plurality of ball tracks 13 are formed by the cooperation of the track grooves 10 a and a plurality of track grooves 12 a provided on the outer peripheral portion of the joint inner ring 12. The ball tracks 13 are formed on the bisector of the ball track 13. A plurality of torque transmission balls 9 held by the cage 14 is disposed. On the outer peripheral surface of the mouth portion 10 on the opening end surface side and the outer peripheral surface of the intermediate shaft 1, boot mounting concave grooves 15 and 16 for attaching the boot 6 are formed, and the large diameter portion and the small diameter portion of the boot 6 are respectively fitted. Further, the outer periphery thereof is fixed by caulking with metal bands 17 and 18.

  Next, the structure of the protective cover 8 of the joint assembly body JA1 will be described.

  The protective cover 8 is made of an elastomer, and a concave groove 24 formed on the outer peripheral surface of the outer joint member 5 of the sliding type constant velocity universal joint 3 is formed on the inner peripheral surface of the inboard side end portion of the protective cover 8. A projection 8b that fits into the groove 8 is formed. By fitting this projection 8b into the groove 24, the mounting position of the protective cover 8 is determined at the end portion on the inboard side.

  On the other hand, a projection 8a is formed on the inner peripheral surface of the end portion on the outboard side of the protective cover 8, and is fitted into the valley portion 6a of the boot 6 attached to the outer joint member 4 of the fixed type constant velocity universal joint 2. By fitting 8a into the trough 6a, the protective cover 8 is attached at the outboard side end.

  At this time, the protrusion 8 a may have a shape that fits into an arbitrary valley portion of the boot 6, but is preferably a protrusion that fits into a valley portion on the large diameter side of the boot 6.

  Further, when the mounting position of the protective cover 8 to the drive shaft is determined on the fixed type constant velocity universal joint 2 side, the locking portion of the protective cover 8 is used as the outer peripheral surface of the outer joint member 4 of the fixed type constant velocity universal joint 2. It is good also as a structure inserted in the ditch | groove formed in this.

  When forming the groove 24, it is desirable not to provide it on the outer peripheral surface of the outer joint member 5 at a position close to the boot mounting groove 22. This is because when the two grooves 22 and 24 are provided close to each other, the thickness of this portion is reduced over a wide range, and the strength of the outer joint member 5 of the sliding type constant velocity universal joint 3 is reduced when a rotational torque is generated. Because it does.

  As described above, since the attachment position of the joint assembly body JA1 of the present embodiment is determined by the inboard side end portion and the outboard side end portion of the protective cover 8, it is easy to attach the protective cover 8 to the drive shaft. Since the protective cover 8 is fixed at both ends even after the attachment, the attachment state of the joint assembly is stable, the backlash is less likely to occur, and the dropout during the vehicle body assembly is prevented.

  FIG. 2 shows a second embodiment (cross-sectional view) of the present invention. In the present embodiment, parts having the same portions, forms, and functions as those in the first embodiment shown in FIG. 1 are denoted by the same reference numerals, and the detailed description thereof will be omitted or simplified in the following description. .

  In the second embodiment, the intermediate shaft 29 is provided with a step portion 29 a having a large diameter on the sliding constant velocity universal joint 3 side and a small diameter on the opposite side, and is provided on the inner peripheral surface of the protective cover 30. Forms a step 30c that engages with the step 29a.

  In the joint assembly body JA2 having such a structure, in the sliding type constant velocity universal joint 3 on the inboard side, the inner joint member can be prevented from slipping out from the outer joint member 5 to the outboard side.

  Similarly to the first embodiment, a concave groove 24 formed on the outer peripheral surface of the outer joint member 5 of the sliding type constant velocity universal joint 3 is formed on the inner peripheral surface of the inboard side end portion of the protective cover 30. A fitting projection 30b is formed, and the fitting position of the protective cover 30 is determined at the end portion on the inboard side by fitting the projection 30b into the concave groove 24.

  Further, on the inner peripheral surface of the end portion on the outboard side of the protective cover 30, a protrusion 30 a that fits into the valley portion 6 a of the boot 6 attached to the outer joint member 4 of the fixed type constant velocity universal joint 2 is formed. By fitting the protrusion 30a into the valley 6a, the mounting position of the protective cover 30 is determined at the end on the outboard side.

  FIG. 3 shows a third embodiment of the present invention. Also in this embodiment, parts having the same portions, forms, and functions as those in the first embodiment shown in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted or simplified in the following description. To do.

  In the third embodiment, the protective cover of the joint assembly body JA3, the first protective cover 31 covering the outer periphery of the fixed type constant velocity universal joint 2 on the outboard side, and the sliding type constant velocity universal on the inboard side are provided. Separated into a second protective cover 32 covering the outer periphery of the joint 3, these protective covers 31, 32 are formed into a cylindrical shape by injection molding a flexible synthetic resin such as PA66. Yes.

  On the inner peripheral surface of the first protective cover 31, there is formed a protrusion 31a that fits into the valley portion 6a of the boot 6 attached to the outer joint member 4 of the fixed type constant velocity universal joint 2, and this protrusion 31a is formed into the valley portion 6a. The attachment position of the protective cover 31 is determined by inserting in.

  Further, on the inner peripheral surface of the second protective cover 32, a protrusion 32a is formed which fits into the groove 24 formed on the outer peripheral surface of the outer joint member 5 of the sliding type constant velocity universal joint 3, and this protrusion 32a. Is inserted into the concave groove 24 to determine the mounting position of the protective cover 32.

  From the above, also in this embodiment, as in the above-described embodiment, it is easy to attach the protective covers 31 and 32 to the drive shaft, and the attached state of the protective covers 31 and 32 is stable after the attachment, and the vehicle body The protective covers 31 and 32 are prevented from falling off during assembly.

  Furthermore, in this embodiment, since the protective cover of the joint assembly body is separated into the protective covers 31 and 32 and separated, these protective covers 31 and 32 are fixed to the fixed type constant velocity universal joint 2 and the sliding type. It can be created in accordance with the shape of each of the quick universal joints 3, can cope with a long intermediate shaft 1, and the cost of the protective cover can be reduced.

  Although not shown, in this embodiment as well, as in the second embodiment shown in FIG. 2, the sliding type constant velocity universal joint side has a large diameter on the outer peripheral surface of the intermediate shaft 1, and A step portion having a small diameter on the opposite side may be provided, and a step portion that engages with the step portion of the intermediate shaft may be formed on the inner peripheral surface of the protective cover.

  As mentioned above, although embodiment of this invention was described, these embodiment is an illustration to the last, and includes all the changes within the meaning and range as described in a claim.

It is sectional drawing which shows 1st Embodiment of the coupling assembly body which concerns on this invention. It is sectional drawing which shows 2nd Embodiment of the coupling assembly body which concerns on this invention. It is sectional drawing which shows 3rd Embodiment of the coupling assembly body which concerns on this invention. It is sectional drawing of the joint assembly body in the past.

Explanation of symbols

8, 30 Protective cover 8a, 8b, 30a, 30b, 31a, 32a Projection 2 Fixed type constant velocity universal joint 4, 5 Outer joint member
3 Sliding type constant velocity universal joints 6, 7 Bellows-shaped boot 6a Valley portions 15, 16, 22, 23 Boot mounting recessed groove 24 Recessed groove 31 First protective cover 32 Second protective cover 1, 29 Intermediate shaft JA1, JA2 , JA3 Joint assembly body N knuckle

Claims (4)

A pair of constant velocity universal joints are attached to both ends of the intermediate shaft, and bellows-like boots are attached between the outer joint members of these constant velocity universal joints and the intermediate shaft, and at least cover the bellows-like boots. in joint assembly body provided with a protective cover, the inner peripheral surface of the constant velocity universal joint side end portion of the protective cover, provided with a locking portion by recess-projection fitting with the mating member opposite to the inner peripheral surface, said pair Of the constant velocity universal joints, one constant velocity universal joint is a sliding type constant velocity universal joint, the sliding type constant velocity universal joint side has a large diameter on the outer peripheral surface of the intermediate shaft, and the opposite side. The joint assembly body is characterized in that a step portion having a small diameter is provided, and a step portion engaging with the step portion of the intermediate shaft is formed on the inner peripheral surface of the protective cover . 2. The joint according to claim 1, wherein the engaging portion of the protective cover is a protrusion, and the protrusion is fitted into a groove formed on the outer peripheral surface of the outer joint member of the sliding type constant velocity universal joint. Assembly body. Of the pair of constant velocity universal joints, the other constant velocity universal joint is a fixed type constant velocity universal joint, and the engaging portion of the protective cover is a projection, and the projection is an outer joint of the fixed type constant velocity universal joint. The joint assembly body according to claim 1, wherein the joint assembly body is fitted into a valley portion of a bellows-like boot attached to the member. The joint assembly according to any one of claims 1 to 3 , wherein the protective cover is separated from one constant velocity universal joint side and the other constant velocity universal joint side.

Images