JP2017219174A - Fixed type equal velocity universal joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve durability by surely preventing outflow of a lubricant to an internal space of a boot from an internal space of an outer joint member.SOLUTION: A fixed type constant velocity universal joint includes a cup-shaped outer joint member 11 having track grooves 16 extending in an axial direction and formed on a plurality of circumferential parts of an inner peripheral face, and an inner joint member 12 accommodated in the outer joint member 11, and having track grooves 18 extending in the axial direction while paired with the track grooves 16 of the outer joint member 11 and formed on a plurality of circumferential parts of an outer peripheral face, and a boot 22 is mounted between an opening portion 21 of the outer joint member 11 and a shaft 15. A partitioning member 28 for preventing a lubricant 20 sealed in an internal space m of the outer joint member 11 from flowing out to the internal space of the boot 22, is disposed between the internal space m of the outer joint member 11 and an internal space n of the boot 22, and the partitioning member 28 is composed of a plurality of partitioning wall portions 29 corresponded to the track grooves 16 of the outer joint member 11 and the rack grooves 18 of the inner joint member 12, and slit portions 30 respectively disposed between the adjacent partitioning wall portions 29.SELECTED DRAWING: Figure 1

Description

  The present invention is used in power transmission systems of automobiles and various industrial machines, such as drive shafts and propeller shafts of automobiles, and is fixed with a boot that prevents foreign matter from entering the joints and preventing lubricant leakage from the joints. It relates to a universal joint.

  For example, there are two types of constant velocity universal joints that are used as means for transmitting a rotational force from an automobile engine to wheels at a constant velocity: a fixed constant velocity universal joint and a sliding constant velocity universal joint. Both of these constant velocity universal joints have a structure in which two shafts on the driving side and the driven side are connected so that rotational torque can be transmitted at a constant speed even if the two shafts have an operating angle.

  A drive shaft that transmits power from the engine to the wheels needs to cope with angular displacement and axial displacement caused by a change in the relative positional relationship between the engine and the wheels. Therefore, the drive shaft is generally equipped with a sliding type constant velocity universal joint on the engine side (inboard side) and a fixed type constant velocity universal joint on the wheel side (outboard side). It has a structure in which universal joints are connected by a shaft.

  In this sliding type constant velocity universal joint or fixed type constant velocity universal joint, by lubricating a lubricant such as grease in the inner space of the outer joint member, the sliding part inside the joint, that is, outside Lubricity is ensured at a sliding portion composed of a joint member, an inner joint member, a ball and a cage.

  In the case of sliding type constant velocity universal joints or fixed type constant velocity universal joints, rubber is used between the outer joint member and the shaft to prevent the leakage of lubricant from the inside of the joint and to prevent foreign matter from entering from the outside of the joint. Or the structure which equipped with the resin-made bellows-like boots is common (for example, refer patent document 1).

  The sliding type constant velocity universal joint disclosed in Patent Document 1 is configured so that the lubricant enclosed in the inner space of the outer joint member does not flow into the inner space of the boot and the inner space of the boot. A structure is provided in which a partition plate that partitions the space is attached to the opening of the outer joint member.

  The partition plate adopted in this sliding constant velocity universal joint is made of a material having flexibility and rubber-like elasticity so that it can respond smoothly to the operation of the shaft even if the penetrating shaft takes an operating angle. ing. Furthermore, the flexibility corresponding to the operating angle of the shaft is enhanced by forming a plurality of cuts on the inner peripheral side of the partition plate.

JP 2008-69848 A

  By the way, in the conventional constant velocity universal joint disclosed in Patent Document 1, a lubricant mainly exists in the track groove of the outer joint member and the track groove of the inner joint member. In this respect, when the notch of the partition plate is located at a position corresponding to the track groove of the outer joint member and the track groove of the inner joint member, the lubricant easily flows out from the inner space of the outer joint member to the inner space of the boot.

  As described above, when the lubricant enclosed in the inner space of the outer joint member easily flows out into the inner space of the boot, the inner space of the outer joint member is secured in order to secure the lubricant present in the inner space of the outer joint member. It is necessary to enclose a large amount of lubricant in advance. As a result, the amount of lubricant enclosed increases.

  On the other hand, an internal part consisting of an inner joint member, a ball and a cage can only be angularly displaced with respect to the outer joint member while the inner part can be displaced axially with respect to the outer joint member. In the case of a fixed type constant velocity universal joint, once the lubricant flows out from the inner space of the outer joint member to the inner space of the boot, it is very difficult to return the lubricant to the inner space of the outer joint member. is there.

  In such a fixed type constant velocity universal joint, if the lubricant flows out from the inner space of the outer joint member to the inner space of the boot, the lubricity in the track groove of the outer joint member and the track groove of the inner joint member is reduced. It will be damaged and the durability will be lowered.

  Therefore, the present invention has been proposed in view of the above-described improvements, and the object of the present invention is to reliably prevent the lubricant from flowing out from the inner space of the outer joint member to the inner space of the boot. It is an object of the present invention to provide a fixed type constant velocity universal joint capable of improving the above.

  The fixed type constant velocity universal joint according to the present invention includes a cup-shaped outer joint member in which track grooves extending in the axial direction are formed at a plurality of locations in the circumferential direction of the inner peripheral surface, and the outer joint member. An inner joint member in which track grooves extending in the axial direction in pairs with the track grooves of the member are formed at a plurality of locations in the circumferential direction of the outer peripheral surface, and an opening portion of the outer joint member and a shaft member extending from the inner joint member; A structure in which boots are mounted between the two.

  As a technical means for achieving the above-mentioned object, the present invention provides a partition member for preventing the lubricant enclosed in the inner space of the outer joint member from flowing into the inner space of the boot. The partition member is disposed between the space and the inner space of the boot, and the partition member is provided between a plurality of partition walls provided corresponding to the track groove of the outer joint member and the track groove of the inner joint member, and between the adjacent partition walls. It is characterized by comprising a slit portion formed.

  In the present invention, the plurality of partition walls constituting the partition member are arranged corresponding to the track grooves of the outer joint member and the track grooves of the inner joint member, so that the lubricant enclosed in the inner space of the outer joint member is The track grooves of the outer joint member and the track grooves of the inner joint member that easily flow out can be closed. As a result, it is possible to reliably prevent the lubricant from flowing from the inner space of the outer joint member to the inner space of the boot.

  Further, since the partition member of the present invention is provided with the slit portion between the adjacent partition wall portions, even if the shaft member that penetrates the partition member takes an operating angle, the flexibility that can smoothly cope with the operation of the shaft member. Can be given.

  Each partition portion of the partition member according to the present invention preferably has a structure in which the inner peripheral side front end portion that contacts the outer peripheral surface of the shaft member is bent to the inner space side of the outer joint member. By adopting such a structure, even when the shaft member takes an operating angle, it becomes difficult for the lubricant to flow out of the track groove, and the sealing performance of the partition wall with respect to the shaft member can be ensured.

  According to the present invention, the track groove of the outer joint member and the track groove of the inner joint member that are likely to flow out of the lubricant sealed in the inner space of the outer joint member can be closed by the partition wall portion of the partition member. As a result, it is possible to reliably prevent the lubricant from flowing from the internal space of the outer joint member to the internal space of the boot, and to reduce the amount of lubricant enclosed. Moreover, even if the shaft member takes an operating angle, the slit portion of the partition member can provide flexibility that can smoothly cope with the operation of the shaft member. From the above, the lubricity of the fixed type constant velocity universal joint can be improved, and the durability can be improved.

It is sectional drawing which shows the whole structure of a fixed type constant velocity universal joint in embodiment of this invention. It is an expanded sectional view which shows the partition member of FIG. It is sectional drawing which follows the PP line | wire of FIG. It is sectional drawing which shows the partition member in other embodiment of this invention. It is sectional drawing which shows the state which the shaft of FIG. 1 took the operating angle.

  An embodiment of a fixed type constant velocity universal joint according to the present invention will be described in detail below with reference to the drawings.

  In the following embodiments, a fixed constant velocity is provided that is incorporated in a drive shaft of an automobile and has a structure in which two shafts on a driving side and a driven side are connected to transmit rotational torque at a constant speed even when the two shafts have an operating angle. An undercut-free constant velocity universal joint, which is one of universal joints, will be exemplified.

  The present invention can be applied to other fixed type constant velocity universal joints such as a Rzeppa type constant velocity universal joint in addition to the undercut-free type constant velocity universal joint.

  A fixed type constant velocity universal joint (hereinafter simply referred to as a constant velocity universal joint) shown in FIG. 1 includes a cup-shaped outer joint member 11, an inner joint member 12, a plurality of balls 13, and a cage 14. ing. An internal part composed of the inner joint member 12, the ball 13, and the cage 14 is accommodated in the outer joint member 11.

  In the outer joint member 11, arc-shaped track grooves 16 extending in the axial direction are formed at a plurality of positions in the circumferential direction of the spherical inner peripheral surface 17 at equal intervals. In the inner joint member 12, arc-shaped track grooves 18 that extend in the axial direction in pairs with the track grooves 16 of the outer joint member 11 are formed at a plurality of positions in the circumferential direction of the spherical outer peripheral surface 19 at equal intervals.

  The opening side portion of the track groove 15 of the outer joint member 11 and the back side portion of the track groove 17 of the inner joint member 12 are formed in a straight shape parallel to the joint axial direction so as to increase the operating angle. Yes. Further, one end of a shaft 15 that is a shaft member is connected to the shaft hole of the inner joint member 12 so that torque can be transmitted by spline fitting.

  The ball 13 is interposed between the track groove 16 of the outer joint member 11 and the track groove 18 of the inner joint member 12 and transmits rotational torque. The cage 14 is disposed between the inner peripheral surface 17 of the outer joint member 11 and the outer peripheral surface 19 of the inner joint member 12 to hold the ball 13.

  In the constant velocity universal joint having the above-described configuration, the lubricant 20 such as grease is sealed in the inner space m of the outer joint member 11, so that the sliding part inside the joint, that is, the outer joint member 11 is operated during the joint operation. Further, the lubricity at the sliding portion constituted by the inner joint member 12, the ball 13 and the cage 14 is secured, and the durability is improved.

  The constant velocity universal joint is made of resin between the opening 21 of the outer joint member 11 and the shaft 15 in order to prevent leakage of the lubricant 20 from the inside of the joint and to prevent foreign matter from entering from the outside of the joint. Alternatively, a structure in which a rubber bellows-like boot 22 is mounted is provided.

  The boot 22 is fastened and fixed by the boot band 25 to the outer peripheral surface of the shaft 15 extending from the inner joint member 12 and the large-diameter end portion 24 fastened and fixed to the outer peripheral surface of the opening 21 of the outer joint member 11. The small-diameter end portion 26, the large-diameter end portion 24, and the small-diameter end portion 26 are connected to each other, and the telescopic bellows portion 27 is contracted from the large-diameter end portion 24 toward the small-diameter end portion 26.

  The fixed type constant velocity universal joint according to the embodiment described above has a structure in which an internal component including the inner joint member 12, the ball 13, and the cage 14 can only be angularly displaced with respect to the outer joint member 11. Therefore, in the fixed type constant velocity universal joint, once the lubricant 20 flows out from the inner space m of the outer joint member 11 to the inner space n of the boot 22, the lubricant 20 is allowed to flow inside the outer joint member 11. It is a structure that is very difficult to return to the space m.

  Therefore, the constant velocity universal joint of this embodiment reliably prevents the lubricant 20 from flowing out from the inner space m of the outer joint member 11 into the inner space n of the boot 22 and improves durability. As shown in FIG. 3, the partition member 28 that prevents the lubricant 20 enclosed in the inner space m of the outer joint member 11 from flowing out into the inner space n of the boot 22 is replaced with the inner space m of the outer joint member 11 and the boot 21. The internal space n is provided with a structure.

  2 and 3, the partition member 28 includes a plurality of partition walls 29 provided corresponding to the track grooves 16 of the outer joint member 11 and the track grooves 18 of the inner joint member 12, and adjacent partition walls. It is comprised with the slit part 30 provided between 29. FIG. The partition member 28 includes a cylindrical portion 31 that integrally extends in the axial direction from an outer peripheral edge that connects the plurality of partition walls 29.

  In addition, since the partition part 29 of the partition member 28 is provided corresponding to the track groove 16 of the outer joint member 11 and the track groove 18 of the inner joint member 12, the slit part 30 of the partition member 28 is adjacent. They are arranged corresponding to the inner peripheral surface 17 of the outer joint member 11 and the outer peripheral surface 19 of the inner joint member 12 positioned between the track grooves 16 and 18.

  As shown in FIG. 1, the partition member 28 has a cylindrical portion 31 mounted on the outer peripheral surface of the opening 21 of the outer joint member 11, and the boot 22 described above is attached to the outer peripheral surface of the cylindrical portion 31. By covering and fixing the cylindrical portion 31 of the partition member 28 together with the large-diameter end portion 24 of the boot 22 by the boot band 23, the partition wall portion 28 and the slit portion 29 are connected to the inner space m of the outer joint member 11 and the boot 22. It is arranged between the internal space n.

  The partition member 28 has an opening 33 through which the shaft 15 penetrates. Even when the shaft 15 takes an operating angle, the partition member 28 has flexibility such as rubber or resin in order to ensure flexibility that can respond smoothly to the operation of the shaft 15. Consists of materials.

  As shown in FIG. 3, the partition wall portion 29 has a substantially triangular shape extending radially inward from the outer peripheral edge of the partition member 28, and the inner peripheral side distal end portion 32 abuts on the outer peripheral surface of the shaft 15. The slit portion 30 has a tapered shape from the opening 33 located at the center toward the outer peripheral edge of the partition member 28, and opens between the adjacent partition walls 29 to enhance the flexibility of the partition wall 29. In addition, the partition part 29 and the slit part 30 may have shapes other than those described above.

  In this embodiment, a six-ball constant velocity universal joint is illustrated, so that the partition member 28 is provided corresponding to the six track grooves 16 and 18 of the outer joint member 11 and the inner joint member 12. There are six partition walls 29.

  In addition to the six-ball constant velocity universal joint, the present invention can also be applied to an eight-ball constant velocity universal joint. In that case, as shown in FIG. 4, the partition member 28 has eight partition walls 29 provided corresponding to the eight track grooves 16 and 18 of the outer joint member 11 and the inner joint member 12. .

  In the constant velocity universal joint of this embodiment, a plurality of partition walls 29 constituting the partition member 28 are arranged in correspondence with the track grooves 16 of the outer joint member 11 and the track grooves 18 of the inner joint member 12, thereby rotating. The lubricant 20 enclosed in the inner space m of the outer joint member 11 with the centrifugal force therein closes the track groove 16 of the outer joint member 11 and the track groove 18 of the inner joint member 12 that are likely to flow out by the extrusion of the ball 13. be able to.

  As a result, the outflow of the lubricant 20 from the internal space m of the outer joint member 11 to the internal space n of the boot 22 can be reliably prevented, and the amount of the lubricant 20 enclosed can be reduced. From the above, the lubricity of the fixed type constant velocity universal joint can be improved, and the durability can be improved.

  Further, since the partition member 28 of this embodiment is provided with the slit portion 30 between the adjacent partition wall portions 29, even if the shaft 15 penetrating the opening 33 of the partition member 28 takes an operating angle, the shaft 15 It is possible to give the partition wall portion 29 the flexibility that can smoothly cope with the above operation.

  As shown in FIG. 1 and FIG. 2, each partition wall portion 29 of the partition member 28 in this embodiment has an inner peripheral side tip portion 32 in contact with the outer peripheral surface of the shaft 15 on the inner space m side of the outer joint member 11. It has a curved shape.

  By adopting such a structure, as shown in FIG. 5, even when the shaft 15 has an operating angle, the inner peripheral side distal end portion 32 of the partition member 28 is securely attached to the outer peripheral surface of the shaft 15. Since they are in contact with each other, it is difficult for the lubricant 20 to flow out of the track grooves 16 and 18, and the sealing performance of the partition wall 29 against the shaft 15 can be ensured.

  The present invention is not limited to the above-described embodiments, and can of course be implemented in various forms without departing from the gist of the present invention. It includes the equivalent meanings recited in the claims and the equivalents recited in the claims, and all modifications within the scope.

11 Outer joint member 12 Inner joint member 15 Shaft member (shaft)
16, 18 Track groove 20 Lubricant 21 Opening 22 Boot 28 Partition member 29 Partition part 30 Slit part 32 Inner peripheral side tip part m, n Internal space

Claims (2)

A cup-shaped outer joint member in which track grooves extending in the axial direction are formed at a plurality of locations in the circumferential direction of the inner peripheral surface, and the axial direction is paired with the track grooves of the outer joint member and accommodated in the outer joint member And a fixed constant velocity with a boot mounted between an opening of the outer joint member and a shaft member extending from the inner joint member. A universal joint,
A partition member for preventing the lubricant encapsulated in the internal space of the outer joint member from flowing out into the internal space of the boot is disposed between the internal space of the outer joint member and the internal space of the boot, and the partition The member is composed of a plurality of partition walls provided corresponding to the track grooves of the outer joint member and the track grooves of the inner joint member, and slit portions provided between adjacent partition walls. Fixed constant velocity universal joint.   2. The fixed type according to claim 1, wherein each partition wall portion of the partition member has a structure in which a distal end portion on an inner peripheral side that comes into contact with an outer peripheral surface of the shaft member is bent toward the inner space side of the outer joint member. Constant velocity universal joint.

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