JP2015001254A - Shaft coupling for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a seal structure which can hold grease and can prevent the intrusion of dust, in a small space and at high-speed rotation, and to provide a shaft coupling for vehicle.SOLUTION: A shaft coupling for vehicle is a constant velocity universal coupling which comprises: an outer side coupling member; an inner side coupling member; a torque transmission member arranged between the outer side coupling member and the inner side coupling member; and a cage for holding the torque transmission member. A seal structure comprises: an outer diameter side ring part attached to an opening end of the outer side coupling member; an inner diameter side ring part attached to an opening end of the inner side coupling member opposing the inner diameter side of the opening end of the outer side coupling member; and a connecting part which connects the outer diameter side ring part and the inner diameter side ring part. The outer diameter side ring part and the inner diameter side ring part are arranged in an overlapping position in a coupling axis direction.

Description

  The present invention relates to a vehicle shaft coupling that connects a motor and a speed reducer of a motor-driven vehicle, and a seal structure used for a vehicle shaft coupling.

  Conventionally, a gear coupling (gear-shaped flexible shaft joint) is used to connect an output shaft of a drive motor and an input shaft of a reduction gear in a railway vehicle.

  FIG. 8 shows a drive device for a railway vehicle. The drive device is a device that transmits the torque of the motor 2 loaded on a bogie frame (not shown) to the driving wheel 3 and includes the shaft coupling 1 and the speed reducer 5. The speed reducer 5 includes a large gear 6 and a small gear 7. The large gear 6 is fixed to a driving wheel shaft 4 having a driving wheel 3 fixed to both ends. The support shaft of the small gear 7 that meshes with the large gear 6 serves as the input shaft of the speed reducer 5, and is connected to the output shaft of the motor 2 by the shaft coupling 1.

  As the shaft coupling 1, a gear-shaped flexible shaft coupling or the like has been used. That is, the gear-shaped flexible shaft coupling has a structure as shown in FIG. In this shaft coupling, an external gear 8 is provided at the shaft end of the output shaft of the motor 2, and an external gear 9 is provided at the shaft end of the small gear 7 of the speed reducer 5, and the internal teeth meshing with the external gears 8, 9. The left and right outer cylinders 10, 11 provided with gears are fastened with bolts 12, a perforated disk-shaped dustproof cover 13 is attached to the outer end surfaces of the left and right outer cylinders 10, 11, and the inner peripheral edge of the dustproof cover 13 is Folded inward and faced into the ring-shaped concave groove 14 formed on the outer side surface of the external gears 8 and 9 without contacting, and the outer surface of the bent portion was fitted to the shaft end as shown by the two-dot chain line It is brought into contact with the worn dust-proof rubber seal 15.

  According to the above-described gear coupling 1, reliable transmission of power can be ensured even if an axial line shift occurs between the motor output shaft and the reduction gear input shaft. However, the gear coupling 1 is required to have angular freedom even when there is a misalignment of several mm or more between the axis of the output shaft of the motor 2 and the input shaft of the speed reducer 5. For this reason, the angle flexibility is enhanced by applying large crowning to the teeth of the external gears 8 and 9. Further, the meshing between the external gears 8 and 9 and the outer cylinders 10 and 11 has a slight clearance (backlash).

  Rail cars are increasingly required to be quiet, just like automobiles. In particular, the vibration noise associated with the backlash of the drive system is a problem. Since the gear coupling 1 connecting the motor and the reduction gear of the railway vehicle has a clearance on the meshing surface of the gear, a rattling sound is generated due to a speed fluctuation during rotation due to the influence of the clearance. Further, when the gear coupling 1 is rotated at an angle, a sliding noise, that is, a so-called rubbing noise between the tooth surfaces is generated as the meshing surfaces of the external gears 8 and 9 and the outer cylinders 10 and 11 slide. To do. There has been a problem of reducing such rattling noise and rubbing noise and reducing vibration noise of the entire vehicle.

  In view of this, a ball type constant velocity joint without backlash has been proposed as a shaft coupling for connecting the motor and the reduction gear (Patent Document 1).

JP 2006-83962 A

  As described above, conventionally, a gear joint, a flexible shaft joint, and a constant velocity universal joint are used between a drive motor and a speed reducer of a railway vehicle. However, the track width (reference gauge, narrow gauge) of the railway vehicle is constant, and the width of the entire vehicle cannot be increased. In the parallel cardan drive method, the space for a joint or the like for connecting the drive motor and the speed reducer is limited. In that limited space, it is necessary to absorb the expansion and contraction in the axial direction and vertical direction of the bogie of the railway vehicle.

  Due to the limited space, the seal is required to have a small space, and it is necessary to have a structure that can cope with high-speed rotation and prevent dust from entering.

  In view of the above problems, the present invention provides a seal structure and a vehicle shaft coupling that can prevent grease retention and dust intrusion with a small space and high-speed rotation.

  The seal structure of the present invention is a seal structure disposed on a vehicle shaft joint that connects a motor and a speed reducer of a motor-driven vehicle, and the vehicle shaft joint includes an outer joint member and an inner joint. This is a constant velocity universal joint that includes a member, a torque transmission member disposed between the outer joint member and the inner joint member, and a cage that holds the torque transmission member, and is attached to the open end of the outer joint member An outer diameter side ring portion, an inner diameter side ring portion mounted on the opening end portion of the inner joint member facing the inner diameter side of the opening end portion of the outer joint member, an outer diameter side ring portion, and an inner diameter side ring portion And an outer diameter side ring part and an inner diameter side ring part are arranged at positions where they are overlapped in the joint axial direction.

  According to the seal structure of the present invention, since the outer diameter side ring portion and the inner diameter side ring portion are arranged at positions where they are overlapped in the joint axial direction, the axial space can be made compact. Can do. In addition, the outer diameter ring part is attached to the open end of the outer joint member, the inner diameter ring part is attached to the open end of the inner joint member, and the entire seal structure is simple and stable. The state can be maintained, and it can sufficiently cope with high-speed rotation.

  A connection part can be comprised from a bellows structure. The outer diameter side ring portion, the inner diameter side ring portion and the connecting portion can be made of a rubber material or a resin material. Examples of the rubber material include natural rubber (NR), isoprene rubber (IR), butadiene rubber (BR), styrene butadiene rubber (SBR), chloroprene rubber (CR), acrylonitrile butadiene rubber (NBR), and the like. As the resin material, thermoplastic elastomers such as ester, olefin, urethane, amide, and styrene can be used.

  The outer diameter side ring portion is preferably press-fitted and fitted to the outer joint member, and the inner diameter side ring portion is preferably press-fitted and fitted to the inner joint member. It is preferable that the outer diameter side ring portion is pressed by an outer diameter side pressing member mounted on the outer joint member, and the inner diameter side ring portion is pressed by an inner diameter side pressing member mounted on the inner joint member.

  The vehicle shaft joint of the present invention is a vehicle shaft joint provided with the seal structure.

  According to the seal structure of the present invention, the space in the axial direction can be made compact, so that the vehicle shaft joint equipped with this seal structure can be made compact. In addition, it is possible to cope with high-speed rotation, the retention of grease inside the joint is stable, and dust and the like can be effectively prevented from entering the joint.

  By adopting a bellows structure, it is excellent in followability to fluctuations of the vehicle shaft joint. Further, the outer diameter side ring portion, the inner diameter side ring portion, and the connecting portion can be made of a rubber material or a resin material, and can be variously changed according to a use site, a use environment, a size, or the like. For this reason, the freedom degree of design becomes large.

  In the case where the outer diameter side ring portion is press-fitted and fitted to the outer joint member and the inner diameter side ring portion is press-fitted and fitted to the inner joint member, it is excellent in mountability and can be made compact.

  When the outer diameter side pressing member and the inner diameter side pressing member are pressed, the seal structure can be more stably attached to the vehicle shaft coupling, and a stable sealing function can be exhibited over a long period of time.

  The vehicle shaft coupling of the present invention can exhibit a compact and stable sealing function. In addition, since the constant velocity universal joint is used, there is no tooth noise or rubbing noise seen in the gear coupling, and the vibration noise of the entire vehicle can be reduced.

It is sectional drawing which shows the shaft coupling for vehicles with which the seal structure of this invention was mounted | worn. FIG. 2 is a cross-sectional view taken along line AA of the vehicle shaft joint illustrated in FIG. 1. It is principal part sectional drawing of the state using a pressing member. It is principal part sectional drawing which shows the shaft coupling for vehicles with which the seal structure which has a bellows part was mounted | worn. It is a front view of the cross groove type constant velocity universal joint used for the shaft coupling for vehicles. It is a development view of the track groove of the cross groove type constant velocity universal joint. It is a simplified diagram of the drive part of an electric vehicle. It is a longitudinal cross-sectional view of the drive device in a railway vehicle. It is sectional drawing which shows a gear-shaped flexible shaft coupling.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. In FIG. 1, the vehicle shaft joint according to the present invention is used in a drive device for a railway vehicle as shown in FIG. 8, and a double offset type constant velocity universal joint T is used. That is, the vehicle shaft joint is integrated in a state where a pair of constant velocity universal joints T and T face each other.

  The constant velocity universal joint T has the same structure, and as shown in FIGS. 1 and 2, the outer joint member 23 in which the track groove 22 is formed on the inner diameter surface 21 and the track groove 25 on the outer diameter surface 24. An inner joint member 26 formed, a ball 27 which is a plurality of torque transmitting members interposed between the track groove 22 of the outer joint member 23 and the track groove 25 of the inner joint member 26 and transmits torque, and the outer joint The main component is a cage 29 that is interposed between the inner diameter surface 21 of the member 23 and the outer diameter surface 24 of the inner joint member 26 and holds the balls 27 accommodated in the pockets 28.

  The center of curvature O1 of the outer peripheral surface 29a of the cage 29 and the center of curvature O2 of the inner peripheral surface 29b are offset in the opposite axial direction with respect to the angle center O of the joint.

  The inner joint member 26 includes a main body portion 31 in which a track groove 25 is formed on the outer diameter surface 24 and a small diameter portion 32 provided continuously to the main body portion 31, and the shaft hole is a tapered hole 30. A taper shaft (not shown) formed on the output shaft of the motor or the support shaft of the small gear is fitted into the taper hole 30 and is fitted by a key structure. Further, a screw shaft portion is formed at the tip of the taper shaft, and the nut member 33 is screwed onto the screw shaft portion protruding from the inner joint member 26 in a state where the taper shaft is fitted into the taper hole 30. The nut member 31 is provided with a ring-shaped cushion material 34.

  The outer joint member 23 has a main body member 35 in which the track groove 22 is formed on the inner diameter surface 21 and an end member 36 attached to the main body member 35. The collar portions 39a and 39b are provided. The end member 36 includes a short cylindrical main body 37 and an outer flange 38 provided at one end of the main body 36 in the axial direction.

  The body member 35 and the end member 36 are integrated with each other by fastening with bolts and nuts (not shown) in a state where the flange portions 38 and 39a are abutted. The pair of constant velocity universal joints T and T are integrated by fastening with bolts and nuts (not shown) in a state where the flange portions 39b and 39b of the outer joint member 23 are abutted with each other. In addition, partition plates 40 and 40 are disposed between the pair of constant velocity universal joints T and T. That is, each main body member 35 is provided with a fitting recess 41 on the end face on one flange 36 side, and a pair of constant velocity universal joints T, T is connected. For this reason, the partition plates 40 and 40 are disposed in a state of being sandwiched between the pair of constant velocity universal joints T and T. A concave groove 42 for fitting a sealing material is formed in the concave portion 41 for fitting, and a sealing material (not shown) such as an O-ring is fitted into the concave groove 42. Further, a groove 43 for fitting a sealing material is formed on the end surface of the end member 36 on the main body member side, and a sealing material (not shown) such as an O-ring is fitted in the groove 43.

  In the vehicle shaft joint, the opening at the end in the axial direction (the opening between the outer joint member 23 and the inner joint member 26) is sealed with the seal structure S according to the present invention. . In this case, the seal structure S includes an outer diameter side ring portion 51 attached to the opening end portion of the outer joint member 23, and an opening end of the inner joint member 26 facing the inner diameter side of the opening end portion of the outer joint member 23. An inner diameter side ring portion 52 attached to the outer diameter side, and a connecting portion 53 that connects the outer diameter side ring portion 51 and the inner diameter side ring portion 52.

  That is, the seal structure S includes a seal body 55 including an outer diameter side ring portion 51, an inner diameter side ring portion 52, and a connection portion 53, and a reinforcing material 56 attached to the outer diameter side ring portion 51 of the seal body 55. And a reinforcing member 57 attached to the inner joint member 26 of the seal body 55.

  The outer diameter side ring part 51 and the inner diameter side ring part 52 are each made of a short cylindrical body, and the axial length of the inner diameter side ring part 52 is made longer than the axial length of the outer diameter side ring part 51. Moreover, the connection part 53 makes cross-sectional flat S shape. The seal body 55 can be made of a rubber material or a resin material. Examples of the rubber material include natural rubber (NR), isoprene rubber (IR), butadiene rubber (BR), styrene butadiene rubber (SBR), chloroprene rubber (CR), acrylonitrile butadiene rubber (NBR), and the like. As the resin material, thermoplastic elastomers such as ester, olefin, urethane, amide, and styrene can be used.

  The reinforcing members 56 and 57 are made of a metal flat ring body, the outer diameter side reinforcing member 56 is disposed on the inner diameter side of the outer diameter side ring portion 51, and the inner diameter side reinforcing material 57 is disposed outside the inner diameter side ring portion 52. It is arranged on the radial side. Moreover, the connection part 53 has connected the outer diameter side ring part 51 and the inner diameter side ring part 52 in the joint back side.

  In this case, a circumferential fitting groove 60 is provided at the open end of the inner diameter surface of the end member 36 of the outer joint member 23, and the circumferential fitting recess of the outer end surface in the axial direction of the outer diameter surface of the inner joint member 26. A groove 61 is provided, and the outer diameter side ring portion 51 of the seal body 55 is press-fitted into the circumferential fitting groove 60 of the outer joint member 23, and the circumferential fitting groove 61 of the inner joint member 26 is sealed. The inner ring side ring portion 52 is press-fit. As a result, the seal structure S can be mounted on the vehicle shaft joint.

  In the mounted state of the seal structure S, the outer diameter side ring portion 51 and the inner diameter side ring portion 52 are disposed at positions overlapped in the joint axial direction. In this embodiment, the axial center line L1 of the outer diameter side ring portion 51 and the axial center line L2 of the inner diameter side ring portion 52 coincide with each other. Further, since the axial length of the inner diameter side ring portion 52 is made longer than the axial length of the outer diameter side ring portion 51, the axial outer end edge 52 a of the inner diameter side ring portion 52 and the shaft of the inner joint member 26 are made. The direction outer end edge slightly protrudes outward in the axial direction from the axial direction outer end edge 51 a of the outer ring portion 51 and the axial direction outer end edge of the outer joint member 23. In this embodiment, an example in which the axial center lines L1 and L2 coincide with each other is shown. However, if the outer diameter side ring portion 51 and the inner diameter side ring portion 52 are substantially in the same position in the joint axial direction, the same compactization is possible. I can plan. The superposition means that the outer diameter side ring portion 51 and the inner diameter side ring portion 52 are not aligned with each other even if the axial center lines L1 and L2 of the outer diameter side ring portion 51 and the inner diameter side ring portion 52 do not coincide with each other. Since it is sufficient that the two are overlapped in the joint axis direction, compactness can be sufficiently achieved even in such a case.

  In the seal structure S, since the outer diameter side ring portion 51 and the inner diameter side ring portion 52 are disposed at positions where they overlap each other in the joint axial direction, the axial space can be made compact. it can. For this reason, the compactness of the vehicle shaft joint to which this seal structure S is attached can be achieved. Moreover, the outer diameter side ring portion 51 is attached to the opening end portion of the outer joint member 23, the inner diameter side ring portion 51 is attached to the opening end portion of the inner joint member 26, and the entire seal structure has a simple structure. , Can maintain a stable wearing state, and can sufficiently cope with high-speed rotation. Further, the holding of the grease inside the joint is stabilized, and dust and the like can be effectively prevented from entering the inside of the joint.

  The outer-diameter side ring portion 51 is press-fitted and fitted to the outer joint member 23, and the inner-diameter side ring portion 52 is press-fitted and fitted to the inner joint member 26. be able to.

  In FIG. 3, the outer diameter side ring portion 51 is pressed by the outer diameter side pressing member 63 attached to the outer joint member 23, and the inner diameter side ring portion 52 is attached to the inner joint member 26. It is holding at 64.

  The outer diameter side pressing member 63 includes a flat plate ring portion 63a fixed to the outer end surface of the outer joint member 23, and an engagement portion 63b extending inward in the axial direction from the outer diameter end of the flat plate ring portion 63a. Then, the flat ring portion 63a is brought into contact with the outer end surface 23a of the outer joint member 23 and is fixed to a screw or the like while being engaged with the outer diameter surface of the outer joint member 23 of the engaging portion 63b in the axial direction end portion. The flat plate ring portion 63a is fixed to the outer end surface 23a of the outer joint member 23 through the tool. Thereby, the outer diameter side ring portion 51 can be held in a state of being pressed against the outer end surface 23 a of the outer joint member 23.

  Further, the inner diameter side pressing member 64 includes a flat plate ring portion fixed to the outer end surface 26a of the inner joint member 26. With the inner diameter side pressing member 64 in contact with the outer end surface 26a of the inner joint member 26, a screw or the like It adheres to the outer end surface 26a of the inner joint member 26 through the fastener. Thereby, the inner diameter side ring portion 52 can be held in a state of being pressed against the outer end surface 26 a of the inner joint member 26.

  In the case of being pressed by the outer diameter side pressing member 63 and the inner diameter side pressing member 64, the seal structure S can be more stably attached to the vehicle shaft joint, and a stable sealing function can be exhibited over a long period of time. .

  In FIG. 4, the connecting portion 53 of the seal body 55 has a bellows structure. In other words, the connecting portion 53 in this case is configured such that the crest portions 65 and the trough portions 66 are alternately arranged. In the seal main body 55, the axial length of the outer diameter side ring portion 51 and the inner diameter side ring portion 52 are set to be the same. Also in this case, the outer diameter side ring portion 51 and the inner diameter side ring portion 52 are arranged at positions where they overlap in the joint axial direction. In FIG. 4, the axial outer end edge 51a of the outer diameter side ring portion 51 and the axial inner end edge 52b of the inner diameter side ring portion 52 are arranged at the same position in the joint axial direction. For this reason, the axial length of the main body 37 of the end member 36 of the outer joint member 23 is set shorter than the end member 36 shown in FIG.

  As shown in FIG. 4, the connecting portion 53 has an accordion structure, and therefore excellent followability to fluctuations of the vehicle shaft joint.

  By the way, in the said embodiment, although the constant velocity universal joint T was a double facet type, a cross-glove type constant velocity universal joint as shown in FIG. 5 may be sufficient. The cross glove type constant velocity universal joint includes an inner joint member 72 having an outer peripheral surface 71 in which ball grooves 70a and 70b inclined in opposite directions with respect to the axis are alternately formed along the circumferential direction, and the axis. The outer joint member 75 having an inner peripheral surface 74 in which ball grooves 73a and 73b inclined in opposite directions are alternately formed along the circumferential direction, and the ball grooves 70a and 70b and the outer joint member 75 of the inner joint member 72. The torque transmission balls 76 incorporated at the intersections of the ball grooves 73a and 73b and the balls 76 as torque transmission members interposed between the inner joint member 72 and the outer joint member 75 at a predetermined interval in the circumferential direction. And a cage 77 for holding.

  FIG. 6 is a developed view of the ball groove. As indicated by the solid line in FIG. 6, the ball grooves 70a and 70b inclined in opposite directions with respect to the axis of the inner joint member 72 are alternately positioned in the circumferential direction. ing. Further, as indicated by a two-dot chain line, ball grooves 73a and 73b inclined in opposite directions with respect to the axis of the outer joint member 75 are alternately positioned in the circumferential direction. A symbol β is an intersection angle of each ball groove 70a, 70b, 73a, 73b with respect to the axis.

  A torque transmitting ball 76 is incorporated at the intersection of the ball groove 70a and the ball groove 73a or the ball groove 70b and the ball groove 73b that form a pair. As shown in FIG. 5, here, there are six ball grooves 70a, 70b of the inner joint member 72 and six ball grooves 73a, 73b of the outer joint member 75, and six torque transmission balls 76. The torque transmission ball 76 is held in a pocket of a cage 77 interposed between the inner joint member 72 and the outer joint member 75.

  The vehicle shaft coupling of the present invention can exhibit a compact and stable sealing function. In addition, since the ball type constant velocity universal joint is used, there is no tooth noise or rubbing noise seen in the gear coupling, and the vibration noise of the entire vehicle can be reduced. In particular, if a cross-groove type constant velocity universal joint as shown in FIGS. 5 and 6 is used for the constant velocity universal joint T, the play in the circumferential direction is less likely to occur, and the vibration noise is further reduced. be able to.

  By the way, you may use for the shaft coupling 80 used for an electric vehicle as shown in FIG. 7 as a shaft coupling for vehicles of this invention. In this case, a shaft coupling 80 is interposed between the motor 70 and a differential (differential) 71. Further, a wheel 73 is attached from the differential 71 via a shaft 72.

  That is, as a vehicle shaft coupling, even an electric vehicle as shown in FIG. 7 can exhibit a compact and stable sealing function. In addition, since the ball type constant velocity universal joint is used, there is no tooth noise or rubbing noise seen in the gear coupling, and the vibration noise of the entire vehicle can be reduced.

  As described above, the embodiment of the present invention has been described. However, the present invention is not limited to the above embodiment, and various modifications are possible. For example, in the seal structure shown in FIG. However, the axial lengths of the outer diameter side ring portion 51 and the inner diameter side ring portion 52 may be the same. In addition, as shown in FIG. 4, when the connecting portion 54 has a bellows structure, in the illustrated example, there are two peaks 65 and valleys 66, but this is not a limitation, and the increase / decrease is not limited to this. Is optional.

  The number of balls of the constant velocity universal joint T is six in each embodiment, but is not limited to six, and may be less than six or more than six. In FIG. 1, the axial outer end edge of the inner joint member 26 protrudes outward in the axial direction from the axial outer end edge of the outer joint member 23, but may not protrude in this way. .

23, 75 Outer joint member 26, 72 Outer joint member 27, 76 Torque transmission member (ball)
29, 77 Cage 51 Outer diameter side ring portion 52 Inner diameter side ring portion 53 Connecting portion 63 Outer diameter side pressing member 64 Inner diameter side pressing member

Claims (7)

A seal structure disposed on a vehicle shaft coupling that connects a motor and a speed reducer of a motor-driven vehicle,
The vehicle shaft joint includes a constant velocity including an outer joint member, an inner joint member, a torque transmission member disposed between the outer joint member and the inner joint member, and a cage that holds the torque transmission member. An outer-diameter ring that is a universal joint and is attached to the opening end of the outer joint member, and an inner-diameter ring that is attached to the opening end of the inner joint member that faces the inner diameter of the opening end of the outer joint And a connecting portion that connects the outer diameter side ring portion and the inner diameter side ring portion, and the outer diameter side ring portion and the inner diameter side ring portion are disposed at positions overlapped in the joint axial direction. Characteristic seal structure.   The seal structure according to claim 1, wherein the connecting portion has a bellows structure.   The seal structure according to claim 1 or 2, wherein the outer diameter side ring portion, the inner diameter side ring portion, and the connecting portion are made of a rubber material.   The seal structure according to any one of claims 1 to 3, wherein the outer diameter side ring portion, the inner diameter side ring portion, and the connecting portion are made of a resin material.   The outer diameter side ring portion is press-fitted and fitted to the outer joint member, and the inner diameter side ring portion is press-fitted and fitted to the inner joint member. To seal structure.   The outer diameter side ring portion is pressed by an outer diameter side pressing member mounted on the outer joint member, and the inner diameter side ring portion is pressed by an inner diameter side pressing member mounted on the inner joint member. Item 6. The seal structure according to Item 5.   A shaft joint for vehicles, wherein the seal structure according to any one of claims 1 to 6 is used.