JP2007247776A - Water entry preventing structure for universal joint boot - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water entry preventing structure for a universal joint boot with a shielding member arranged on an inner ring of a ring-shaped supporting member for a mounted member for covering a fitting portion of the boot to the mounted member, thus improving the balancing accuracy of the mounted member, reducing the weight of components around the mounted member and improving the sealing performance. <P>SOLUTION: In the water entry preventing structure for the universal joint boot 60, the inner ring 31 of the ring-shaped supporting member 30 has a straight cylinder portion 81 from which the outer peripheral face of the inner ring 31 is exposed to an outer ring 32 and a gumlike elastic member 33 at a position protruding outward in the axial direction and the shielding member 70 is detachably mounted on the straight cylinder portion 81 of the inner ring 31. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a structure for preventing water and the like from entering a universal joint boot used in a propeller shaft or the like.

  In a conventional vehicle, a propeller shaft that transmits engine output to a rear wheel is divided in the axial direction, and the divided front and rear shafts are connected by a universal joint. Then, use a boot to prevent the intrusion of dust, muddy water, etc. into the connection space between the outer and inner of the universal joint.

  The boot for a universal joint disclosed in Patent Document 1 avoids abnormal expansion / contraction or breakage of the boot in response to a change in the internal pressure of the boot based on a temperature change due to the heat generated by the universal joint or a change in the internal pressure of the boot based on the slide of the universal joint. A groove-shaped internal pressure adjusting communication passage that communicates the inside and outside of the boot with the fitting portion to the inner is provided.

  In the universal joint of Patent Document 1, a communication passage that communicates with the inside and outside of the boot is provided at the fitting portion of the boot to the inner portion. Such water easily enters the boot from the communication path. If a large amount of water enters the boot, the joint function will be impaired by rusting of the universal joint.

Therefore, in Patent Document 2, when the center bearing loaded on the side of the fitting portion of the boot in the inner is supported by the annular support member, the fitting portion of the boot is radially and axially attached to the inner ring of the annular support member. A shielding member to be covered is provided. The shielding member covers the periphery of the fitting portion to the inner of the boot in the radial direction and the axial direction, shields water from the outside world, and water from the outside to the internal pressure adjusting communication path provided in the fitting portion. It prevents intrusion due to wraparound.
JP-A-8-28704 JP2005-180618

  In the universal joint disclosed in Patent Document 2, the shielding member provided on the inner ring of the annular support member impairs balancing to adjust the rotation balance of the propeller shaft.

  In other words, the propeller shaft is balanced by supporting the inner ring from the outer peripheral side with a jig that does not interfere with the outer ring at a position where the inner ring of the annular support member protrudes axially outward with respect to the outer ring. The propeller shaft is rotated at a high speed to measure the balance of the propeller shaft, and a weight is attached to the propeller shaft based on the measurement result to remove the unbalance of the propeller shaft.

  However, when a shielding member is provided on the inner ring of the annular support member and the small-diameter fitting portion to the inner of the boot is covered in the radial direction and the axial direction by the shielding member, the outer member of the boot is directed toward the outer side in the axial direction. The outside air that expands beyond the outer diameter of the large-diameter fitting portion to the outside and flows around the universal joint from the front to the rear is increased from the small-diameter fitting portion to the inner part of the boot by the outer periphery of the expanding portion of the shielding member. It is preferable to prevent the water or the like caught in the flow of outside air from entering the small diameter fitting portion and entering the internal pressure adjusting communication passage. For this reason, the outer peripheral surface of the inner ring of the annular support member provided with the shielding member becomes a widened slope, and a balancing jig cannot be stably fastened to the outer peripheral surface of the inner ring. It is difficult to improve the accuracy of

  The outer peripheral surface of the inner ring of the annular support member is covered with a soft rubber-like elastic member over the entire length in the axial direction, and the outer peripheral surface of the inner ring is stably positioned at a predetermined position by a jig for balancing. However, it is difficult to improve the accuracy of balancing.

  Further, when a shielding member is integrally provided on the inner ring of the annular support member and the integral is made of metal, it is difficult to reduce the weight of the peripheral parts of the propeller shaft.

  An object of the present invention is to provide a waterproof member intrusion prevention structure for a universal joint boot in which a shielding member that covers a fitting portion of a boot to a mounted member is provided on an inner ring of an annular support member for the mounted member. This makes it possible to improve the accuracy of balancing and to reduce the weight of the parts around the mounted member.

  According to the first aspect of the present invention, when one end portion of the boot that seals the connection space of the universal joint is fitted and attached to the attached member, the inside and outside of the boot communicate with the fitting portion of the boot to the attached member. A center bearing loaded on the side of the fitting part of the boot in the mounted member is supported by the annular support member, and the annular support member is supported by the inner ring that supports the center bearing and the mounting bracket. A shield having an outer ring and an annular rubber-like elastic member provided between the inner ring and the outer ring, and covering the inner ring of the annular support member with the fitting portion of the boot in the radial direction and the axial direction. In the structure for preventing intrusion of water or the like of a universal joint boot provided with a member, an outer peripheral surface of the inner ring at a position where the inner ring of the annular support member protrudes axially outward with respect to the outer ring and the rubber-like elastic member It has a straight cylindrical part that exposes the inner ring. Those fitted with a shielding member detachably on Jo tubular portion.

  According to a second aspect of the present invention, in the first aspect of the present invention, the shielding member has a C-shape in which a slit is provided in a part of the circumferential direction, and the mounting portion is fitted to the straight cylindrical portion of the inner ring. An attachment pin that is engaged with and disengaged from a locking hole provided in the straight cylindrical portion is provided.

  In the invention of claim 3, when the one end portion of the boot that seals the connection space of the universal joint is fitted and attached to the attached member, the inside and outside of the boot communicate with the fitting portion of the boot to the attached member. A center bearing loaded on the side of the fitting part of the boot in the mounted member is supported by the annular support member, and the annular support member is supported by the inner ring that supports the center bearing and the mounting bracket. A shield having an outer ring and an annular rubber-like elastic member provided between the inner ring and the outer ring, and covering the inner ring of the annular support member with the fitting portion of the boot in the radial direction and the axial direction. In the structure for preventing intrusion of water or the like of a universal joint boot provided with a member, an outer peripheral surface of the inner ring at a position where the inner ring of the annular support member protrudes axially outward with respect to the outer ring and the rubber-like elastic member It has a straight cylindrical part that exposes the inner ring. The extending portion further extending axially outward from Jo tube portion, in which is mounted the shielding member.

  The invention according to claim 4 is the invention according to any one of claims 1 to 3, wherein a small diameter fitting portion at one end of the boot is attached to one attached member, and a large diameter attaching portion at the other end of the boot. Is attached to the other attached member, and when the small-diameter fitting portion of the boot is covered in the radial direction and the axial direction by the shielding member, the shielding member expands beyond the outer diameter of the large-diameter attachment portion of the boot. And facing the front surface of the large-diameter mounting portion.

  According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the shielding member is made of rubber or synthetic resin.

(Claim 1)
(a) In the inner ring of the annular support member, a straight cylindrical portion is provided at a position protruding outward in the axial direction with respect to the outer ring and the rubber-like elastic member, and the shielding member can be attached to and detached from the straight cylindrical portion. Accordingly, the positioning jig for balancing can be stably fastened to the outer peripheral surface of the straight cylindrical portion of the inner ring before the shielding member is attached, and the accuracy of balancing can be improved.

  (b) Since the outer peripheral surface of the straight cylindrical portion of the inner ring of the annular support member is exposed and does not go through a coating such as rubber, the outer peripheral surface of the straight cylindrical portion of the inner ring is directly applied by a positioning jig for balancing. Can be supported stably and the accuracy of balancing can be improved.

(Claim 2)
(c) Since the shielding member has a C shape, the shielding member having the slits can be easily incorporated from the outside in the radial direction around the attached member after balancing. By attaching the mounting pin provided on the attaching portion of the shielding member to the engaging hole provided in the straight cylindrical portion of the inner ring, the shielding member can be attached to the inner ring without using a fastening band or the like.

(Claim 3)
(d) In the inner ring of the annular support member, a straight cylindrical portion is provided at a position protruding outward in the axial direction with respect to the outer ring and the rubber-like elastic member, and extends further outward in the axial direction from the straight cylindrical portion. A shielding member was attached to the extended portion. Therefore, the positioning jig for balancing can be stably fastened to the straight outer peripheral surface of the straight cylindrical portion of the inner ring to which the shielding member is attached, and the accuracy of balancing can be improved.

  (e) Since the outer peripheral surface of the straight cylindrical portion of the inner ring of the annular support member is exposed and there is no coating of rubber or the like, the outer peripheral surface of the straight cylindrical portion of the inner ring is directly applied by a positioning jig for balancing. Can be supported stably and the accuracy of balancing can be improved.

(Claim 4)
(f) When the shielding member covers the small-diameter fitting portion of the boot in the radial direction and the axial direction, the shielding member expands beyond the outer diameter of the large-diameter mounting portion of the boot and the front surface of the large-diameter mounting portion To face. Therefore, the outside air flowing around the universal joint from the front to the rear is guided outwardly by the outer periphery of the expanding portion of the shielding member so as to be largely separated from the small-diameter fitting portion of the boot, and consequently the large-diameter mounting portion of the boot. It will flow away from the periphery. This prevents water or the like caught in the flow of outside air around the universal joint from entering the small diameter fitting portion of the boot and entering the internal pressure adjusting communication passage.

(Claim 5)
(g) By forming the shielding member with rubber or synthetic resin, it is possible to improve the rust prevention and lightness of the shielding member. Even if the inner ring of the annular support member is formed of metal, the peripheral member to be mounted can be reduced in weight by forming the shielding member separate from the inner ring with rubber or synthetic resin.

  1 is a cross-sectional view showing a structure for preventing water and the like from entering the universal joint boot according to the first embodiment, FIG. 2 is an enlarged view of a main part of FIG. 1, FIG. 3 is a shielding member, (A) is a cross-sectional view, ) Is a front view, FIG. 4 is a cross-sectional view showing a balanced state of the propeller shaft, FIG. 5 is a cross-sectional view showing a structure for preventing water and the like from entering the universal joint boot, and FIG. 6 is a rear view showing a shielding member. It is.

Example 1 (FIGS. 1 to 4)
FIG. 1 shows a constant velocity universal joint (slidable joint) 20 comprising a first propeller shaft 11 connected to one of the engine side and the drive side, and a second propeller shaft 12 connected to the other of the engine side and the drive side. The connected parts are indicated by. In this embodiment, the first propeller shaft 11 is connected to the drive side, the second propeller shaft 12 is connected to the engine side, the first propeller shaft 11 side is located rearward, and the second propeller shaft 12 side is It will be located forward.

  The universal joint 20 has an outer 21 connected to the first propeller shaft 11 and an inner 23 formed at the tip of a shaft stub 22 connected to the second propeller shaft 12, and the ball 24 is connected to the outer periphery of the inner 23. It is configured by fitting between three grooves 23B and 21A provided at three positions between the surface and the inner peripheral surface of the outer 21.

  The shaft stub 22 of the second propeller shaft 12 is reduced in diameter from the large-diameter portion 22A toward the inner portion 23 at the tip portion in order, such as a medium-diameter portion 22B and a small-diameter portion 22C, and is passed through a center bearing 25 loaded in the small-diameter portion 22C. The annular support member 30 is rotatably supported by the annular support member 30, and the annular support member 30 is fixed to the vehicle body side by a mounting bracket 30A.

  The annular support member 30 includes a metal inner ring 31 that supports the center bearing 25, a metal outer ring 32 that is supported by the mounting bracket 30 </ b> A, and an annular rubber-like elastic provided between the inner ring 31 and the outer ring 32. And a member 33. In other words, the annular support member 30 is formed by joining an inner ring 31 and an outer ring 32 via a rubber-like elastic member 33, and the inner ring 31 has a small diameter part 31A, a medium diameter part 31B, and a large diameter part 31C. The outer ring 25A of the center bearing 25 is fitted inside the medium diameter part 31B, the small diameter part 31A extends to the front covering the outer periphery of the medium diameter part 22B of the shaft stub 22, The large diameter portion 31 </ b> C extends rearward to cover the outer periphery of the small diameter portion 22 </ b> C of the shaft stub 22. Further, in the inner ring 31, seal members 34 and 35 are loaded on the inner circumferences of the small diameter portion 31A and the large diameter portion 31C, respectively, and both the seal members 34 and 35 seal the center bearing 25 from both sides. The seal member 35 is in sliding contact with the outer periphery of a stopper piece 40 described later on the rear surface side of the center bearing 25, and the seal member 34 is in sliding contact with the outer periphery of the medium diameter portion 22 </ b> B of the shaft stub 22 on the front surface side of the center bearing 25.

  In the universal joint 20, the center bearing 25 fitted to the inner ring 31 of the annular support member 30 is loaded into the small diameter portion 22 </ b> C of the shaft stub 22, and in this state, the small diameter portion 22 </ b> C of the shaft stub 22 is annular. The stopper piece 40 is press-fitted. The front end portion of the stopper piece 40 penetrates the inside of the seal member 35 and abuts the rear end surface of the center bearing 25. As a result, the front end surface of the inner ring 25B of the center bearing 25 is positioned in contact with the shoulder surface of the medium diameter portion 22B of the shaft stub 22, and the rear end surface of the inner ring 25B is pressed against the front end surface of the stopper piece 40 and positioned. .

  The stopper piece 40 includes a large diameter flange portion 41 and a small diameter flange portion 42. The large-diameter flange portion 41 of the stopper piece 40 is close to the inner periphery of the rear end of the inner ring 31 of the annular support member 30 and prevents water from entering the inner ring 31 that houses the center bearing 25. Further, the water that has entered from the gap between the large diameter flange portion 41 and the inner ring 31 is guided by the annular groove 43 between the large diameter flange portion 41 and the small diameter flange portion 42 and falls downward, and enters the inner ring 31. To prevent the ingress of water.

  Further, in the universal joint 20, as shown in FIG. 2, the connection space 50 between the outer 21 and the inner 23 is sealed using a boot adapter 51 made of a thin metal plate and a boot 60 made of a rubber-like elastic body. -Grease for improving the slidability and durability of the rod 24 is sealed in the connection space 50. The boot 60 prevents entry of dust, muddy water, and the like into the connection space 50.

  The boot adapter 51 includes a base 51A that is inserted around a sealing member 52 such as an O-ring provided on the outer periphery of the outer 21 and is fastened and fixed, and extends in the axial direction of the inner 23 so as to cover the boot 60 from the base 51A. It has a tip 51B.

  The boot 60 is made of a flexible material such as rubber, and has a large cylindrical large-diameter mounting portion 61 that is clamped and fixed to the distal end portion 51B of the boot adapter 51 on the first propeller shaft 11 side. A small cylindrical small-diameter fitting portion 62 is fitted to the outer circumferential fitting portion 23A of the inner 23 on the second propeller shaft 12 side and fixedly attached to the outer circumferential fitting portion 23A by a boot band 65. Further, the boot 60 has a substantially U-shaped cross section between the large-diameter mounting portion 61 and the small-diameter fitting portion 62 and has a bent portion 63 that bends inwardly into the connection space 50.

  The boot 60 has a small-diameter fitting portion 62 extending from the front end of the fitting cylinder portion 62A and a fitting cylinder portion 62A that is connected to the outer circumferential fitting portion 23A in a manner connected to the bending portion 63 to form a free end. And it shall consist of the sealing cylinder part 62B sealed on the outer periphery of the inner 23. FIG. At a plurality of positions in the circumferential direction of the inner circumference of the fitting cylinder portion 62A in the small diameter fitting portion 62, the axial space extending in the axial direction extends through the connection space 50 inside the boot 60 to the inner circumference side of the sealing cylinder portion 62B. A groove-shaped communication passage 64 (the passage 64 may be provided on the outer peripheral fitting portion 23A side) is provided for enabling communication. The sealing cylinder part 62B connected to the fitting cylinder part 62A can be easily expanded / contracted with respect to the outer periphery of the inner 23 in response to a change in the internal pressure of the boot 60, and the diameter is expanded when the internal pressure of the boot 60 is increased. The communication path 64 of 62A is opened to the outside so that the internal pressure of the boot 60 can be released to the outside, and when the internal pressure of the boot 60 is lowered, the diameter is reduced to enable the communication path 64 of the fitting tube portion 62A to be sealed.

  In the boot 60 of the present embodiment, the small-diameter fitting portion 62 includes only the fitting tube portion 62A, and it is not essential to include the sealing tube portion 62B.

  However, in the universal joint 20, as shown in FIG. 2, the small-diameter fitting part 62 (the fitting cylinder part 62 </ b> A and the sealing cylinder part 62 </ b> B) of the boot 60 is radially arranged on the inner ring 31 of the annular support member 30. And the shielding member 70 covered in an axial direction is provided.

  At this time, the inner ring 31 of the annular support member 30 is formed so that the surface of the outer peripheral surface of the inner ring 31 protrudes outward in the axial direction with respect to the outer ring 32 and the rubber-like elastic member 33. The cylindrical member 81 is exposed to the outside without being covered with the shield member 70, and the shielding member 70 is detachably attached to the straight cylindrical member 81 of the inner ring 31. In the inner ring 31 of the first embodiment, the small-diameter portion 31A and the medium-diameter portion 31B are covered with the rubber-like elastic member 33, and the large-diameter portion 31C is not covered with the rubber-like elastic member 33. A cylindrical portion 81 is formed.

  As shown in FIG. 3, the shielding member 70 has a substantially cylindrical shape and is formed in a C shape having a slit 70 </ b> A in a part in the circumferential direction, and is a straight shape fitted on the outer periphery of the straight cylindrical portion 81 of the inner ring 31. A plurality of (three in this embodiment) mounting pins 71A that are engaged with and disengaged from locking holes 81A provided at a plurality of circumferential positions (three in this embodiment) of the straight cylindrical portion 81 are attached to the mounting portion 71. Prepare. When the mounting pin 71A of the straight mounting portion 71 of the shielding member 70 is engaged with the locking hole 81A of the straight cylindrical portion 81 of the inner ring 31, the both end surfaces sandwiching the slit 70A of the shielding member 70 collide with each other, Close the slit 70A.

The shielding member 70 has an expanded portion 72 that expands outward from the straight attachment portion 71 in the axial direction. The expanding portion 72 includes an outer peripheral taper 72A continuous with the straight attachment portion 71, an expanded flat plate portion 72B continuous with the outer peripheral taper 72A, and an expanded cylindrical portion 72C continuous with the expanded flat plate portion 72B. The expanding portion 72 of the shielding member 70 extends from the straight mounting portion 71 fitted to the straight cylindrical portion 81 of the inner ring 31 to the large-diameter mounting portion 61 of the boot 60 (the distal end portion 51B of the boot adapter 51) in the radial direction. ) Expands to a larger diameter than the outer peripheral diameter, faces the front surface of the large-diameter mounting portion 61, and extends to a position surrounding at least a part of the small-diameter fitting portion 62 of the boot 60 in the axial direction.
The shielding member 70 is made of rubber or synthetic resin.

  When the small-diameter fitting portion 62 of the boot 60 includes only the fitting cylinder portion 62A and does not include the sealing cylinder portion 62B, the axially extending end of the expanding portion 72 of the shielding member 70 is the fitting cylinder portion 62A. It is set so as to surround the rear end part beyond the front end (free end).

  The propeller shafts 11 and 12 connected by the universal joint 20 are balanced as shown in FIG. At a position where the inner ring 31 of the annular support member 30 protrudes axially outward with respect to the outer ring 32 and the rubber-like elastic member 33, in this embodiment, at the straight cylindrical part 81 (large diameter part 31 C), the outer ring 32. The straight cylindrical portion 81 is supported on the rotating shaft from the outer peripheral side by the positioning jig 100 that does not interfere with the rotation. The positioning jig 100 has three claws 101 arranged equally in the circumferential direction, and supports three positions in the circumferential direction of the straight cylindrical portion 81 from the outer peripheral side. The propeller shafts 11 and 12 are rotated at a high speed to measure the balance of the propeller shafts 11 and 12, and weights are attached to the propeller shafts 11 and 12 based on the measurement results to remove the unbalance of the propeller shafts 11 and 12.

According to the present embodiment, the following operational effects can be obtained.
(a) In the inner ring 31 of the annular support member 30, a straight cylindrical portion 81 is provided at a position protruding outward in the axial direction with respect to the outer ring 32 and the rubber-like elastic member 33, and a shielding member is provided on the straight cylindrical portion 81. 70 was made removable. Accordingly, the positioning jig 100 for balancing can be stably fastened to the straight outer peripheral surface of the straight cylindrical portion 81 of the inner ring 31 before the shielding member 70 is attached, and the accuracy of balancing is improved. it can.

  (b) Since the outer peripheral surface of the straight cylindrical portion 81 of the inner ring 31 of the annular support member 30 is exposed and does not include a coating of rubber or the like, the straight cylindrical portion of the inner ring 31 is used by the positioning jig 100 for balancing. The outer peripheral surface of 81 can be directly and stably supported, and the accuracy of balancing can be improved.

  (c) Since the shielding member 70 has a C-shape, the shielding member 70 having the slit 70A opened can be easily incorporated from the outside in the radial direction around the inner 23 after balancing. By attaching the mounting pin 71A provided on the mounting portion 71 of the shielding member 70 to the locking hole 81A provided on the straight cylindrical portion 81 of the inner ring 31, the shielding member 70 can be moved inside without using a fastening band or the like. It can be attached to the ring 31.

  (d) When the shielding member 70 covers the small-diameter fitting portion 62 of the boot 60 in the radial direction and the axial direction, the shielding member 70 expands beyond the outer diameter of the large-diameter mounting portion 61 of the boot 60. It faces the front surface of the large-diameter mounting portion 61. Accordingly, the outside air that flows around the universal joint 20 from the front to the rear is guided outward by the outer periphery of the expanding portion 72 of the shielding member 70 so as to be largely separated from the small-diameter fitting portion 62 of the boot 60. The periphery of the large-diameter mounting portion 61 flows away backward. This prevents water or the like caught in the ambient air flow around the universal joint 20 from entering the small diameter fitting portion 62 of the boot 60 and entering the internal pressure adjusting communication passage 64.

  (e) By forming the shielding member 70 from rubber or synthetic resin, the rust prevention property and light weight of the shielding member 70 can be improved. Even if the inner ring 31 of the annular support member 30 is made of metal, the inner ring 31 and the shielding member 70 that is a separate member can be made of rubber or synthetic resin, thereby reducing the weight of the peripheral parts around the inner 23. it can.

Example 2 (FIGS. 5 and 6)
The second embodiment is different from the first embodiment in that a shielding member 90 is provided on the inner ring 31 of the annular support member 30. The shielding member 90 covers the small-diameter fitting part 62 (the fitting cylinder part 62A and the sealing cylinder part 62B) of the boot 60 in the radial direction and the axial direction.

  At this time, the inner ring 31 of the annular support member 30 is formed so that the surface of the outer peripheral surface of the inner ring 31 protrudes outward in the axial direction with respect to the outer ring 32 and the rubber-like elastic member 33. The shielding member 90 is attached to an extending portion 82 that has a straight cylindrical portion 81 that is exposed to the outside without being covered by the outer ring and extends further outward in the axial direction from the straight cylindrical portion 81 of the inner ring 31. The extending portion 82 of the present embodiment has a tapered shape that expands outward in the axial direction. In the inner ring 31 of the present embodiment, the small-diameter portion 31A and the medium-diameter portion 31B are covered with the rubber-like elastic member 33, and the large-diameter portion 31C is not covered with the rubber-like elastic member 33. A cylindrical portion 81 and an extending portion 82 are formed.

  As shown in FIG. 6, the shielding member 90 has a generally annular shape, and has a tapered attachment portion 91 that is engaged with the outer periphery of the extension portion 82 of the inner ring 31. The tapered inner peripheral surface of the tapered mounting portion 91 is fitted to the tapered outer peripheral surface of the extending portion 82 of the inner ring 31, and the step portion 91 </ b> A of the tapered inner peripheral surface of the tapered mounting portion 91 is fitted to the inner ring 31. The shielding member 90 can be fixedly attached to the extending portion 82 of the inner ring 31 by engaging with the outer end surface of the extending portion 82. When the shielding member 90 is made of rubber as will be described later, before the outer 21 is connected to the inner 23, the extension portion 82 of the inner ring 31 of the annular support member 30 incorporated around the inner 23 is The tapered mounting portion 91 of the shielding member 90 is elastically enlarged and deformed, the tapered mounting portion 91 is placed on the outer periphery of the extending portion 82, and the stepped portion 91 </ b> A of the tapered mounting portion 91 whose diameter is restored is reduced. The extension portion 82 can be engaged with the outer end surface. Further, when the shielding member 90 is made of a synthetic resin as will be described later, the extending portion 82 of the inner ring 31 of the annular support member 30 incorporated around the inner 23 is a stage before the outer 21 is connected to the inner 23. (In this case, the extending portion 82 includes slits reaching the outer end along the axial direction of the extending portion 82 at a plurality of positions in the circumferential direction), and extends the tapered attachment portion 91. The stepped portion 91 </ b> A of the tapered mounting portion 91 can be engaged with the outer end surface of the extending portion 82 that covers the outer periphery of the portion 82 and expands the diameter in a regenerative manner.

The shielding member 90 has an expanded portion 92 that expands outward from the tapered mounting portion 91 in the axial direction. The expansion portion 92 includes an expansion taper portion 92A that is continuous with the tapered attachment portion 91, an expansion flat plate portion 92B that is continuous with the expansion taper portion 92A, and an expansion cylinder portion 92C that is continuous with the expansion flat plate portion 92B. The widened portion 92 of the shielding member 90 extends from the tapered mounting portion 91 engaged with the extending portion 82 of the inner ring 31 to the large-diameter mounting portion 61 of the boot 60 in the radial direction (the tip portion 51B of the boot adapter 51). It expands to a larger diameter than the outer peripheral diameter of the large diameter, faces the front surface of the large diameter mounting portion 61, and extends to a position surrounding at least a portion of the small diameter fitting portion 62 of the boot 60 in the axial direction.
The shielding member 90 is made of rubber or synthetic resin.

  When the small-diameter fitting portion 62 of the boot 60 includes only the fitting tube portion 62A and does not include the sealing tube portion 62B, the axially extending end of the expanding portion 92 of the shielding member 90 is the fitting tube portion 62A. It is set so as to surround the rear end part beyond the front end (free end).

  The propeller shafts 11 and 12 connected by the universal joint 20 are balanced as shown by a two-dot chain line in FIG. At a position where the inner ring 31 of the annular support member 30 protrudes axially outward with respect to the outer ring 32 and the rubber-like elastic member 33, in this embodiment, at the straight cylindrical part 81 (large diameter part 31 C), the outer ring 32. The straight cylindrical portion 81 is supported from the outer peripheral side by the positioning jig 100 that does not interfere with the outer periphery. The positioning jig 100 has three claws 101 arranged at equal intervals in the circumferential direction, and supports three positions in the circumferential direction of the straight cylindrical portion 81 on the rotation axis from the outer peripheral side. The propeller shafts 11 and 12 are rotated at a high speed to measure the balance of the propeller shafts 11 and 12, and a weight is attached to the propeller shafts 11 and 12 based on the measurement result to remove the unbalance of the propeller shafts 11 and 12. .

According to the present embodiment, the following operational effects can be obtained.
(a) In the inner ring 31 of the annular support member 30, a straight cylindrical portion 81 is provided at a position protruding outward in the axial direction with respect to the outer ring 32 and the rubber-like elastic member 33, and the shaft is further extended from the straight cylindrical portion 81. The shielding member 90 was attached to the extended part 82 extended outward in the direction. Accordingly, the positioning jig 100 for balancing can be stably fastened to the straight outer peripheral surface of the straight cylindrical portion 81 of the inner ring 31 to which the shielding member 90 is attached, and the accuracy of balancing can be improved. .

  (b) Since the outer peripheral surface of the straight cylindrical portion 81 of the inner ring 31 of the annular support member 30 is exposed and is not covered with rubber or the like, the straight cylindrical portion of the inner ring 31 is used by the positioning jig 100 for balancing. The outer peripheral surface of 81 can be directly and stably supported, and the accuracy of balancing can be improved.

  (c) When the shielding member 90 covers the small-diameter fitting portion 62 of the boot 60 in the radial direction and the axial direction, the shielding member 90 expands beyond the outer diameter of the large-diameter mounting portion 61 of the boot 60. It faces the front surface of the large-diameter mounting portion 61. Accordingly, the outside air that flows around the universal joint 20 from the front to the rear is guided outwardly by the outer periphery of the expanding portion 92 of the shielding member 90 so as to be largely separated from the small-diameter fitting portion 62 of the boot 60. The periphery of the large-diameter mounting portion 61 flows away backward. This prevents water or the like caught in the ambient air flow around the universal joint 20 from entering the small diameter fitting portion 62 of the boot 60 and entering the internal pressure adjusting communication passage 64.

  (d) By forming the shielding member 90 from rubber or synthetic resin, the rust prevention and weight reduction of the shielding member 90 can be improved. Even if the inner ring 31 of the annular support member 30 is made of metal, the inner ring 31 and the shielding member 90 that is separate from the inner ring 31 are made of rubber or synthetic resin, thereby reducing the weight of the peripheral parts of the inner 23. it can.

  The embodiment of the present invention has been described with reference to the drawings. However, the specific configuration of the present invention is not limited to this embodiment, and even if there is a design change or the like without departing from the gist of the present invention. Included in the invention.

FIG. 1 is a cross-sectional view showing a structure for preventing water and the like from entering the universal joint boot according to the first embodiment. FIG. 2 is an enlarged view of a main part of FIG. FIG. 3 shows a shielding member, (A) is a sectional view, and (B) is a front view. FIG. 4 is a cross-sectional view showing a balanced state of the propeller shaft. FIG. 5 is a cross-sectional view showing a structure for preventing water and the like from entering the universal joint boot according to the second embodiment. FIG. 6 is a rear view showing the shielding member.

Explanation of symbols

20 Universal joint 21 Outer (member to be mounted)
23 Inner (attached member)
25 Center bearing 30 Ring support member 31 Inner ring 32 Outer ring 33 Rubber elastic member 50 Connection space 60 Boot 61 Large diameter mounting portion 62 Small diameter fitting portion 64 Communication path 70 Shielding member 70A Slit 71 Mounting portion 71A Mounting pin 72 Expand Part 81 Straight cylindrical part 81A Locking hole 82 Extension part 90 Shielding member 91 Attachment part 92 Widening part

Claims (5)

When the one end of the boot that seals the connection space of the universal joint is fitted and attached to the attached member, a communication passage is provided to connect the inside and outside of the boot to the fitting portion of the boot to the attached member;
The center bearing loaded on the side of the fitting part of the boot in the mounted member is supported by the annular support member,
The annular support member includes an inner ring that supports the center bearing, an outer ring that is supported by the mounting bracket, and an annular rubber-like elastic member that is provided between the inner ring and the outer ring.
In the structure for preventing intrusion of water and the like of the universal joint boot, which is provided with a shielding member for covering the fitting portion of the boot in the radial direction and the axial direction on the inner ring of the annular support member,
The inner ring of the annular support member has a straight cylindrical portion exposing the outer peripheral surface of the inner ring at a position protruding axially outward with respect to the outer ring and the rubber-like elastic member;
A structure for preventing intrusion of water or the like in a universal joint boot, wherein a shielding member is detachably attached to a straight cylindrical portion of an inner ring.   The shielding member has a C-shape with a slit in a part in the circumferential direction, and is engaged with and disengaged from a locking hole provided in the straight cylindrical portion at an attachment portion fitted to the straight cylindrical portion of the inner ring. The structure for preventing water and the like from entering the universal joint boot according to claim 1, further comprising a mounting pin. When the one end of the boot that seals the connection space of the universal joint is fitted and attached to the attached member, a communication passage is provided to connect the inside and outside of the boot to the fitting portion of the boot to the attached member;
The center bearing loaded on the side of the fitting part of the boot in the mounted member is supported by the annular support member,
The annular support member includes an inner ring that supports the center bearing, an outer ring that is supported by the mounting bracket, and an annular rubber-like elastic member that is provided between the inner ring and the outer ring.
In the structure for preventing intrusion of water and the like of the universal joint boot, which is provided with a shielding member for covering the fitting portion of the boot in the radial direction and the axial direction on the inner ring of the annular support member,
The inner ring of the annular support member has a straight cylindrical portion exposing the outer peripheral surface of the inner ring at a position protruding axially outward with respect to the outer ring and the rubber-like elastic member;
A structure for preventing intrusion of water or the like of a universal joint boot, characterized in that a shielding member is attached to an extending portion that extends further outward in the axial direction from a straight cylindrical portion of an inner ring.   A small-diameter fitting portion at one end of the boot is attached to one attached member, a large-diameter attaching portion at the other end of the boot is attached to the other attached member, and the small-diameter fitting portion of the boot is attached by the shielding member. When covering in the radial direction and the axial direction, the shielding member expands beyond the outer diameter of the large-diameter mounting portion of the boot and faces the front surface of the large-diameter mounting portion. Prevents water from entering the universal joint boot.   The structure for preventing intrusion of water or the like of a universal joint boot according to any one of claims 1 to 4, wherein the shielding member is formed of rubber or synthetic resin.

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