JP2019006268A - Dust cover - Google Patents

Abstract

To provide a dust cover capable of improving sealability for a clearance between a steering shaft and a dash panel.SOLUTION: The dust cover includes: a bush fitted on an outer-peripheral surface of a steering shaft penetrating through a cylindrical member of a dash panel; an annular bellows filling a clearance between the cylindrical member and the bush; a cylindrical fitting member pressing the bush against the cylindrical member. The fitting member has a first groove which is an annular groove on an outer-peripheral surface. The bellows includes: a bush fitting part in contact with an outer-peripheral surface of the bush; a first fitting part fitted onto the first groove; a first flexible part connecting the bush fitting part with the first fitting part; a second fitting part which is positioned at the first fitting part on the opposite side to the first flexible part and is in contact with the fitting member; and a second flexible part which connects the bush fitting part with the second fitting part and is sandwiched between the cylindrical member and the first fitting part.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a dust cover disposed in a gap between a steering shaft and a dash panel.

  A steering device provided in a vehicle includes a steering shaft for transmitting rotation of a steering wheel to a wheel. The steering shaft passes through a dash panel that separates the vehicle compartment from the engine compartment. Since the steering shaft moves in accordance with adjustment of the position of the steering wheel or vibration during traveling, a predetermined gap is provided between the steering shaft and the dash panel. On the other hand, it is necessary to prevent the outside air including foreign matter such as dust and the like and the sound generated in the engine room from entering the vehicle interior. For this reason, a dust cover is provided in the gap between the steering shaft and the dash panel. For example, Patent Document 1 describes an example of a dust cover.

International Publication No. 2005/068277

  By the way, a dust cover that can further enhance the sealing performance of the gap between the steering shaft and the dash panel may be required.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a dust cover that can improve the sealing performance of the gap between the steering shaft and the dash panel.

  In order to achieve the above object, a dust cover according to an aspect of the present invention includes a bush attached to an outer peripheral surface of a steering shaft that penetrates a cylindrical member of a dash panel, and a gap between the cylindrical member and the bush. An annular bellows that closes the cylindrical member, and a cylindrical mounting member that presses the bellows against the cylindrical member, the mounting member including a first groove that is an annular groove on an outer peripheral surface, and the bellows A bush fitting portion in contact with an outer peripheral surface of the bush, a first fitting portion fitted in the first groove, a first flexible portion connecting the bush fitting portion and the first fitting portion, and the first A second fitting part located on the opposite side of the first flexible part with respect to the first fitting part and in contact with the mounting member; the bush fitting part and the second fitting part; and A second flexible member sandwiched between the tubular member and the first fitting portion And, equipped with a.

  Thereby, when a cylindrical member is clamp | tightened with a band, the part between a cylindrical member and an attachment member among bellows will be compressed. Between the cylindrical member and the mounting member, the first fitting portion and the second flexible portion are overlapped. For this reason, a deformation | transformation of a 1st fitting part and a 2nd flexible part tends to become large. Even when the first fitting portion and the second flexible portion move in the radial direction due to vibration of the vehicle or the like, the deformation of the first fitting portion and the second flexible portion is restored. Thereby, the sealing of the clearance gap between a cylindrical member and an attachment member is maintained. Therefore, the dust cover can improve the sealing performance of the gap between the steering shaft and the dash panel.

  As a desirable mode of the dust cover, it is desirable that the first groove overlaps an annular band attached to the tubular member in the radial direction of the steering shaft. Thereby, the first fitting portion is easily pressed against the inner wall of the first groove. As a result, the gap between the cylindrical member and the mounting member is more easily sealed.

  As a desirable mode of the dust cover, it is desirable that both ends of the first groove in the axial direction of the steering shaft overlap the band in the radial direction. Thereby, the first fitting portion is easily pressed against the inner wall of the first groove. As a result, the gap between the cylindrical member and the mounting member is more easily sealed.

  As a desirable mode of the dust cover, it is desirable that the attachment member includes a main body portion provided with the first groove and a flange portion protruding from the main body portion toward a radially outer side of the steering shaft. Thereby, since it becomes possible to contact a flange part with a cylindrical member, positioning of a dust cover becomes easy.

  As a desirable mode of the dust cover, it is desirable that the mounting member includes a second groove, which is an annular groove into which the second fitting portion is fitted, on an outer peripheral surface. Accordingly, the first fitting portion is caught on the inner wall of the first groove, and the second fitting portion is caught on the inner wall of the second groove. Therefore, the bellows will not be detached from the mounting member.

  As a desirable mode of the dust cover, it is desirable that the bellows includes a first protrusion protruding from the first fitting portion toward the second fitting portion. Thereby, the first protrusion is pressed against the mounting member together with the first fitting portion. For this reason, the clearance gap between a cylindrical member and an attachment member becomes easier to seal.

  As a desirable mode of the dust cover, it is desirable that the bellows includes a second protrusion that protrudes from the second fitting portion toward the side opposite to the first fitting portion. Thereby, the second protrusion is pressed against the attachment member together with the second fitting portion. For this reason, the clearance gap between a cylindrical member and an attachment member becomes easier to seal.

  As a desirable mode of the dust cover, the mounting member is preferably made of synthetic resin or aluminum alloy. This reduces the weight of the dust cover.

  As a desirable mode of the dust cover, a seal lip that closes a gap between the steering shaft and the bush is provided, and the seal lip is preferably integral with the bush. As a result, the seal lip suppresses leakage of sound generated in the engine room to the vehicle compartment. Further, since a member for fixing the seal lip to the bush is unnecessary, the dust cover is reduced in weight.

  As a desirable mode of the dust cover, it is desirable that the bush fitting portion includes a third protrusion that is deformed by a reaction force from the bush. Thereby, when the bush fitting portion moves relative to the bush, the deformed third protrusion is restored. Since the state in which the third protrusion is in contact with the bush is maintained, the sealing performance of the gap between the bush fitting portion and the bush is maintained.

  As a desirable mode of the dust cover, it is desirable that a concave portion is provided on one of the outer peripheral surface of the bush and the inner peripheral surface of the bush fitting portion, and a convex portion that fits in the concave portion is provided on the other. Thereby, the relative rotation of a bush and a bush fitting part is suppressed. As a result, the sealing performance of the gap between the bush and the bush fitting portion is improved.

  ADVANTAGE OF THE INVENTION According to this invention, the dust cover which can improve the sealing performance of the clearance gap between a steering shaft and a dash panel can be provided.

FIG. 1 is a schematic diagram of a steering apparatus according to the present embodiment. FIG. 2 is a perspective view of the steering apparatus of the present embodiment. FIG. 3 is a cross-sectional view of the dust cover attached to the vehicle. FIG. 4 is an enlarged view of the periphery of the attachment member in FIG. FIG. 5 is a perspective view of the band of the present embodiment. FIG. 6 is a front view of the dust cover of the present embodiment. 7 is a cross-sectional view taken along line AA in FIG. FIG. 8 is a cross-sectional view of the bellows before being attached to the bush. FIG. 9 is a cross-sectional view of the bellows immediately after being taken out from the mold. 10 is a cross-sectional view taken along the line BB in FIG. FIG. 11 is a cross-sectional view of the bush of this embodiment. 12 is a cross-sectional view taken along the line CC in FIG. FIG. 13 is a cross-sectional view of the periphery of the attachment member in the first modification. FIG. 14 is a cross-sectional view of the periphery of the attachment member in the second modification. FIG. 15 is a cross-sectional view of the periphery of the attachment member in the third modification.

  Hereinafter, the present invention will be described in detail with reference to the drawings. The present invention is not limited by the following modes for carrying out the invention (hereinafter referred to as embodiments). In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art, those that are substantially the same, and those in a so-called equivalent range. Furthermore, the constituent elements disclosed in the following embodiments can be appropriately combined.

(Embodiment)
FIG. 1 is a schematic diagram of a steering apparatus according to the present embodiment. FIG. 2 is a perspective view of the steering apparatus of the present embodiment. As shown in FIG. 1, the steering device 80 includes a steering wheel 81, a first steering shaft 82, a steering force assist mechanism 83, a first universal joint 84, a second steering shaft 85, and a second universal joint 86. And is joined to the third steering shaft 87. In the following description, the front in the vehicle on which the steering device 80 is mounted is simply described as the front, and the rear in the vehicle is simply described as the rear.

  As shown in FIG. 1, the first steering shaft 82 includes an input shaft 82a and an output shaft 82b. One end of the input shaft 82a is connected to the steering wheel 81, and the other end of the input shaft 82a is connected to the output shaft 82b. One end of the output shaft 82 b is connected to the input shaft 82 a, and the other end of the output shaft 82 b is connected to the first universal joint 84.

  As shown in FIG. 1, the second steering shaft 85 connects the first universal joint 84 and the second universal joint 86. One end of the second steering shaft 85 is connected to the first universal joint 84, and the other end is connected to the second universal joint 86. One end of the third steering shaft 87 is connected to the second universal joint 86, and the other end of the third steering shaft 87 is connected to the steering gear 88. As shown in FIG. 2, the second steering shaft 85 passes through the dash panel 10. The dash panel 10 is a partition plate that separates the vehicle compartment from the engine compartment.

  As shown in FIG. 1, the steering gear 88 includes a pinion 88a and a rack 88b. The pinion 88 a is connected to the third steering shaft 87. The rack 88b meshes with the pinion 88a. The steering gear 88 converts the rotational motion transmitted to the pinion 88a into a linear motion by the rack 88b. The rack 88 b is connected to the tie rod 89. The angle of the wheels changes as the rack 88b moves.

  As shown in FIG. 1, the steering force assist mechanism 83 includes a speed reducer 92 and an electric motor 93. The speed reducer 92 is, for example, a worm speed reducer. Torque generated by the electric motor 93 is transmitted to the worm wheel via the worm inside the speed reducer 92 and rotates the worm wheel. The reduction gear 92 increases the torque generated by the electric motor 93 by the worm and the worm wheel. The speed reducer 92 gives auxiliary steering torque to the output shaft 82b. That is, the steering device 80 is a column assist system.

  As shown in FIG. 1, the steering device 80 includes an ECU (Electronic Control Unit) 90, a torque sensor 94, and a vehicle speed sensor 95. The electric motor 93, the torque sensor 94, and the vehicle speed sensor 95 are electrically connected to the ECU 90. The torque sensor 94 outputs the steering torque transmitted to the input shaft 82a to the ECU 90 by CAN (Controller Area Network) communication. The vehicle speed sensor 95 detects the traveling speed (vehicle speed) of the vehicle body on which the steering device 80 is mounted. The vehicle speed sensor 95 is provided in the vehicle body and outputs the vehicle speed to the ECU 90 by CAN communication.

  The ECU 90 controls the operation of the electric motor 93. The ECU 90 acquires signals from each of the torque sensor 94 and the vehicle speed sensor 95. The ECU 90 is supplied with electric power from a power supply device 99 (for example, an in-vehicle battery) with the ignition switch 98 being on. The ECU 90 calculates an auxiliary steering command value based on the steering torque and the vehicle speed. The ECU 90 adjusts the power value supplied to the electric motor 93 based on the auxiliary steering command value. The ECU 90 acquires information on the induced voltage from the electric motor 93 or information output from a resolver or the like provided in the electric motor 93. As the ECU 90 controls the electric motor 93, the force required to operate the steering wheel 81 is reduced.

  FIG. 3 is a cross-sectional view of the dust cover attached to the vehicle. FIG. 4 is an enlarged view of the periphery of the attachment member in FIG. FIG. 5 is a perspective view of the band of the present embodiment. FIG. 6 is a front view of the dust cover of the present embodiment. 7 is a cross-sectional view taken along line AA in FIG. FIG. 8 is a cross-sectional view of the bellows before being attached to the bush. FIG. 9 is a cross-sectional view of the bellows immediately after being taken out from the mold. 10 is a cross-sectional view taken along the line BB in FIG. FIG. 11 is a cross-sectional view of the bush of this embodiment. 12 is a cross-sectional view taken along the line CC in FIG.

  In the following description, the direction along the rotation axis Z of the second steering shaft 85 is described as the axial direction, the direction orthogonal to the axial direction is described as the radial direction, and the direction along the circle around the rotation axis Z is the circumferential direction. It is described. In FIG. 3, the right side is the vehicle compartment side, and the left side is the engine room side.

  As shown in FIG. 3, the dash panel 10 includes a cylindrical member 101. The inner peripheral surface of the cylindrical member 101 faces the outer peripheral surface of the second steering shaft 85. The second steering shaft 85 may move with adjustment of the position of the steering wheel 81 or vibration during traveling. Therefore, an annular gap is provided between the inner peripheral surface of the cylindrical member 101 and the outer peripheral surface of the second steering shaft 85. In order to close this gap, the steering device 80 includes a dust cover 1.

  The dust cover 1 is fitted on the inner peripheral surface of the cylindrical member 101. The dust cover 1 is fixed to the cylindrical member 101 by a band 7 attached to the outer peripheral surface of the cylindrical member 101. The tubular member 101 is deformed by being fastened by the band 7. For example, the cylindrical member 101 is made of metal. When the cylindrical member 101 is a metal, it is preferable that the cylindrical member 101 has the slit 102 along the axial direction as shown in FIG. Since the cylindrical member 101 has the slits 102, the cylindrical member 101 is easily deformed when the band 7 is tightened.

  As shown in FIG. 5, the band 7 includes an inner member 71 and an outer member 72. The inner member 71 and the outer member 72 are made of metal, for example. The outer member 72 overlaps the outer peripheral surface of the inner member 71. The inner member 71 includes a claw 715 protruding from the outer peripheral surface, and a grip portion 711. The outer member 72 includes a long hole 720 and a grip portion 721. The claw 715 is located inside the elongated hole 720. When a force in a direction approaching the grip portion 711 and the grip portion 721 is applied, the inner diameter of the inner member 71 decreases. When the inner diameter of the inner member 71 reaches a predetermined size, the claw 715 comes into contact with the end of the elongated hole 720. Thereby, the inner diameter of the inner member 71 does not become a predetermined size or less. When the inner diameter of the inner member 71 reaches a predetermined size, the claw 715 is positioned by, for example, a stopper projecting from the inner wall of the elongated hole 720. Thereby, since the inner member 71 and the outer member 72 do not move relatively, the state where the band 7 clamps the tubular member 101 is maintained.

  As shown in FIG. 7, the dust cover 1 includes a bellows 2, a bush 5, a seal lip 11, a seal lip 12, and an attachment member 6. The bellows 2, the bush 5, the seal lip 11, the seal lip 12, and the mounting member 6 are each formed in an annular shape. The bellows 2 is made of rubber, for example. As shown in FIG. 7, the bellows 2 includes a bush fitting portion 20, a first fitting portion 22, a first flexible portion 21, a second fitting portion 26, and a second flexible portion 25, Is provided.

  The bush fitting portion 20 is located at the radially inner end of the bellows 2. The bush fitting portion 20 is fitted into the bush 5. As shown in FIGS. 8 and 10, the bush fitting portion 20 includes a third protrusion 28, a third protrusion 29, and a convex portion 201. The third protrusion 28 protrudes from the bush fitting portion 20 to the engine room side. The third protrusion 29 protrudes from the bush fitting portion 20 toward the passenger compartment. In a state where the bush fitting portion 20 is fitted in the bush 5, the third protrusion 28 and the third protrusion 29 are pushed by the bush 5 and deformed. The convex portion 201 is provided on the inner peripheral surface of the bush fitting portion 20. For example, four convex portions 201 are arranged at equal intervals in the circumferential direction.

  The first fitting portion 22 is fitted to the attachment member 6. The first flexible portion 21 connects the bush fitting portion 20 and the first fitting portion 22. As shown in FIG. 7, the first flexible portion 21 is substantially U-shaped in the cross section including the rotation axis Z. The second fitting portion 26 is fitted to the attachment member 6. The second flexible part 25 connects the bush fitting part 20 and the second fitting part 26. As shown in FIG. 7, the second flexible portion 25 is substantially U-shaped in the cross section including the rotation axis Z. The first flexible part 21 and the second flexible part 25 are connected by a bush fitting part 20.

  The bellows 2 which is rubber is molded using, for example, a mold. As shown in FIG. 9, the shape of the first flexible portion 21 in the bellows 2 taken out from the mold is different from the shape of the first flexible portion 21 in the bellows 2 after being attached to the bush 5. In order to facilitate the removal of the bellows 2 from the mold, the first flexible portion 21 has a bent portion 211 as shown in FIG. The bent portion 211 is convex toward the opposite side to the second flexible portion 25. For this reason, the first flexible portion 21 is substantially S-shaped in the cross section including the rotation axis Z. The bent portion 211 is turned over until the bellows 2 is attached to the bush 5. That is, the bent portion 211 is pushed toward the second flexible portion 25. Thereby, the bellows 2 becomes a shape as shown in FIG. When the bent portion 211 is turned over, the second fitting portion 26 approaches the second fitting portion 26. For this reason, the operation | work which fits the 2nd fitting part 26 to the attachment member 6 becomes easy.

  The bush 5 is a bearing that rotatably supports the second steering shaft 85. The bush 5 is made of nylon, for example. As shown in FIG. 11, the bush 5 includes a base 50, an outer flange 51, an inner flange 52, and a plurality of lubricant grooves 59.

  The base 50 is in contact with the second steering shaft 85. The base 50 includes a recess 501 on the outer peripheral surface. For example, the number of recesses 501 is four. Four concave portions 501 are arranged at equal intervals in the circumferential direction. The convex part 201 shown in FIG. 10 fits into the concave part 501. Thereby, the bush fitting portion 20 does not rotate with respect to the base portion 50. Thereby, the relative rotation of the bellows 2 and the bush 5 is restricted.

  The outer flange 51 protrudes radially outward from the end of the base 50 on the engine room side. The inner flange 52 protrudes radially outward from the end of the base 50 on the passenger compartment side. The bush fitting portion 20 of the bellows 2 is fitted into a space formed by the base 50, the outer flange 51, and the inner flange 52. The lubricant groove 59 is a groove provided on the inner peripheral surface of the base portion 50 and is, for example, along the axial direction. The lubricant groove 59 extends over the entire length of the bush 5 in the axial direction. For example, a plurality of lubricant grooves 59 are arranged at equal intervals in the circumferential direction. The lubricant groove 59 is filled with grease as a lubricant. Thereby, the friction between the bush 5 and the second steering shaft 85 is reduced.

  As shown in FIG. 11, the axial distance W50 from the outer flange 51 to the inner flange 52 is smaller than the width W20 shown in FIG. The width W <b> 20 is the total axial length of the bush fitting portion 20 including the third protrusion 28 and the third protrusion 29. When the bush fitting portion 20 is disposed between the outer flange 51 and the inner flange 52, the third protrusion 28 and the third protrusion 29 are compressed by the outer flange 51 and the inner flange 52. That is, the third protrusion 28 and the third protrusion 29 are deformed in the axial direction. Since the 3rd protrusion 28 and the 3rd protrusion 29 contact | adhere to the bush 5, the clearance gap between the bush fitting part 20 and the bush 5 is sealed. Furthermore, when an axial load is applied to the bush fitting portion 20 due to vibration or the like, the deformed third protrusion 28 or third protrusion 29 is restored. For this reason, the state in which the third protrusion 28 or the third protrusion 29 is in contact with the bush 5 is maintained. Even when a load is applied to the bush fitting portion 20, the sealing performance of the gap between the bush fitting portion 20 and the bush 5 is maintained.

  Further, the inner diameter D20 of the bush fitting portion 20 shown in FIG. 10 is smaller than the outer diameter D50 of the base portion 50 shown in FIG. When the bush fitting portion 20 is attached to the base portion 50, the bush fitting portion 20 is deformed in the radial direction. For this reason, the bush fitting portion 20 is in close contact with the bush 5. For this reason, the clearance gap between the bush fitting part 20 and the bush 5 is sealed.

  The seal lip 11 is a sealing member that separates the gap between the second steering shaft 85 and the bush 5 from the engine room. The seal lip 11 is, for example, nitrile rubber (NBR), and is integrated with the bush 5 by vulcanization adhesion. As shown in FIG. 11, the seal lip 11 protrudes from the end surface of the bush 5 toward the engine room. The minimum inner diameter of the seal lip 11 before coming into contact with the second steering shaft 85 is smaller than the outer diameter of the second steering shaft 85. For this reason, when the seal lip 11 contacts the second steering shaft 85, the seal lip 11 is deformed. Due to the elasticity of the seal lip 11, a gap between the seal lip 11 and the second steering shaft 85 is less likely to occur. For this reason, the seal lip 11 can prevent entry of foreign matter from the engine room to the inside of the bush 5 and can prevent leakage of grease from the inside of the bush 5 to the engine room. Moreover, the seal lip 11 can suppress leakage of sound generated in the engine room to the passenger compartment.

  The seal lip 12 is a sealing member that separates the gap between the second steering shaft 85 and the bush 5 from the vehicle compartment. The seal lip 12 is, for example, nitrile rubber (NBR), and is integrated with the bush 5 by vulcanization adhesion. As shown in FIG. 11, the seal lip 12 protrudes from the end surface of the bush 5 toward the vehicle compartment. The minimum inner diameter of the seal lip 12 before coming into contact with the second steering shaft 85 is smaller than the outer diameter of the second steering shaft 85. For this reason, when the seal lip 12 contacts the second steering shaft 85, the seal lip 12 is deformed. Due to the elasticity of the seal lip 12, a gap between the seal lip 12 and the second steering shaft 85 is less likely to occur. For this reason, the seal lip 12 can prevent leakage of grease from the inside of the bush 5 to the vehicle interior. Moreover, the seal lip 12 can suppress leakage of sound generated in the engine room to the passenger compartment.

  The attachment member 6 is a member that presses the bellows 2 against the cylindrical member 101 shown in FIG. The attachment member 6 is made of, for example, an aluminum alloy. The attachment member 6 may be formed of a synthetic resin. As shown in FIG. 4, the attachment member 6 includes a main body portion 61 and a flange portion 62. The main body 61 has a cylindrical shape and includes an annular first groove 611 on the outer peripheral surface. The first fitting portion 22 of the bellows 2 is fitted in the first groove 611. The flange portion 62 protrudes outward from the main body portion 61 in the radial direction. As shown in FIG. 4, the attachment member 6 is positioned by the flange portion 62 coming into contact with the tubular member 101. The second fitting portion 26 is fitted in the gap between the flange portion 62 and the first fitting portion 22. A part of the second flexible part 25 is sandwiched between the first fitting part 22 and the tubular member 101. A part of the first flexible portion 21 is sandwiched between the second flexible portion 25 and the attachment member 6.

  The inner diameter D22 (see FIG. 8) of the first fitting portion 22 before the bellows 2 is attached to the attachment member 6 is smaller than the outer diameter D61 (see FIG. 7) of the main body portion 61. For this reason, the bellows 2 is fitted to the attachment member 6 while being extended in the radial direction. Since the bellows 2 tightens the attachment member 6, the bellows 2 is not easily detached from the attachment member 6. For this reason, even before the dust cover 1 is mounted on the vehicle, the state in which the bellows 2 is fitted to the mounting member 6 is maintained. Therefore, the operation | work which attaches the dust cover 1 to a vehicle becomes easy.

  Since the tubular member 101 is fastened by the band 7, a portion of the bellows 2 between the tubular member 101 and the attachment member 6 is compressed. That is, the 1st fitting part 22, the 1st flexible part 21, the 2nd fitting part 26, and the 2nd flexible part 25 are compressed. Thereby, the clearance gap between the cylindrical member 101 and the attachment member 6 is sealed. Further, the first fitting portion 22 is caught on the inner wall of the first groove 611 and the second fitting portion 26 is caught on the first fitting portion 22. For this reason, the bellows 2 is not detached from the mounting member 6.

  As shown in FIG. 4, the first groove 611 overlaps the band 7 in the radial direction. For example, the length L611 of the first groove 611 in the axial direction is smaller than the length L7 of the band 7 in the axial direction. In the radial direction, both ends of the first groove 611 in the axial direction overlap the band 7. Thereby, the first fitting portion 22 is easily pressed against the inner wall of the first groove 611. As a result, the gap between the tubular member 101 and the attachment member 6 is more easily sealed.

  The band 7 does not necessarily have the structure described above. The band 7 is not particularly limited as long as the tubular member 101 can be tightened. The band 7 is sometimes called a binding band or a hose band.

  Note that the cylindrical member 101 is not necessarily made of metal. For example, the cylindrical member 101 may be formed of synthetic resin or rubber. When the cylindrical member 101 is a synthetic resin or rubber, the cylindrical member 101 may not have the slit 102 shown in FIG.

  In addition, in the manufacturing process of the bellows 2, the bending part 211 shown in FIG. 9 does not necessarily need to be reversed. That is, the bellows 2 may have the shape shown in FIG. 8 when it is removed from the mold. Moreover, the bellows 2 does not necessarily need to be rubber, for example, may be an elastomer or the like.

  Note that the bush fitting portion 20 does not necessarily include the convex portion 201 as illustrated in FIG. 10, and the bush 5 does not necessarily include the concave portion 501 as illustrated in FIG. 12. The bush fitting portion 20 may include a concave portion instead of the convex portion 201, and the bush 5 may include a convex portion instead of the concave portion 501.

  As described above, the dust cover 1 includes the bush 5, the bellows 2, and the attachment member 6. The bush 5 is attached to the outer peripheral surface of the second steering shaft 85 that penetrates the cylindrical member 101 of the dash panel 10. The bellows 2 is an annular member that closes a gap between the tubular member 101 and the bush 5. The attachment member 6 is a cylindrical member that presses the bellows 2 against the cylindrical member 101. The attachment member 6 includes a first groove 611 that is an annular groove on the outer peripheral surface. The bellows 2 includes a bush fitting portion 20, a first fitting portion 22, a first flexible portion 21, a second fitting portion 26, and a second flexible portion 25. The bush fitting portion 20 is in contact with the outer peripheral surface of the bush 5. The first fitting portion 22 is fitted in the first groove 611. The first flexible portion 21 connects the bush fitting portion 20 and the first fitting portion 22. The second fitting portion 26 is located on the side opposite to the first flexible portion 21 with respect to the first fitting portion 22 and is in contact with the attachment member 6. The second flexible portion 25 connects the bush fitting portion 20 and the second fitting portion 26 and is sandwiched between the tubular member 101 and the first fitting portion 22.

  As a result, when the tubular member 101 is tightened by the band 7, a portion of the bellows 2 between the tubular member 101 and the attachment member 6 is compressed. Between the cylindrical member 101 and the attachment member 6, the first fitting portion 22 and the second flexible portion 25 overlap each other. For this reason, the deformation of the first fitting portion 22 and the second flexible portion 25 tends to be large. Even when the first fitting portion 22 and the second flexible portion 25 move in the radial direction due to vibration of the vehicle, the deformation of the first fitting portion 22 and the second flexible portion 25 is restored. Thereby, sealing of the clearance gap between the cylindrical member 101 and the attachment member 6 is maintained. Therefore, the dust cover 1 can improve the sealing performance of the gap between the steering shaft and the dash panel 10.

  Moreover, in the dust cover 1, the 1st groove | channel 611 overlaps with the cyclic | annular band 7 attached to the cylindrical member 101 in radial direction. Thereby, the first fitting portion 22 is easily pressed against the inner wall of the first groove 611. As a result, the gap between the tubular member 101 and the attachment member 6 is more easily sealed.

  In the dust cover 1, both ends of the first groove 611 in the axial direction overlap the band 7 in the radial direction. Thereby, the first fitting portion 22 is easily pressed against the inner wall of the first groove 611. As a result, the gap between the tubular member 101 and the attachment member 6 is more easily sealed.

  In the dust cover 1, the attachment member 6 includes a main body portion 61 provided with the first groove 611 and a flange portion 62 that protrudes outward from the main body portion 61 in the radial direction. As a result, the flange portion 62 can be brought into contact with the tubular member 101, so that the dust cover 1 can be easily positioned.

  Moreover, in the dust cover 1, the attachment member 6 is a synthetic resin or an aluminum alloy. Thereby, the dust cover 1 is reduced in weight.

  In addition, the dust cover 1 includes a seal lip 11 and a seal lip 12 that block a gap between the second steering shaft 85 and the bush 5. The seal lip 11 and the seal lip 12 are integral with the bush 5. Thereby, the seal lip 11 and the seal lip 12 suppress the leakage of the sound generated in the engine room to the passenger compartment. Further, since a member for fixing the seal lip 11 and the seal lip 12 to the bush 5 is unnecessary, the dust cover 1 is reduced in weight.

  Further, in the dust cover 1, the bush fitting portion 20 includes a third protrusion 28 and a third protrusion 29 that are deformed by a reaction force from the bush 5. Thereby, when the bush fitting part 20 moves with respect to the bush 5, the deformed third protrusion 28 and third protrusion 29 are restored. Since the state where the third protrusion 28 or the third protrusion 29 is in contact with the bush 5 is maintained, the sealing performance of the gap between the bush fitting portion 20 and the bush 5 is maintained.

  In the dust cover 1, a concave portion 501 is provided on one of the outer peripheral surface of the bush 5 and the inner peripheral surface of the bush fitting portion 20, and a convex portion 201 that fits into the concave portion 501 is provided on the other side. Thereby, the relative rotation of the bush 5 and the bush fitting part 20 is suppressed. As a result, the sealing performance of the gap between the bush 5 and the bush fitting portion 20 is improved.

(First modification)
FIG. 13 is a cross-sectional view of the periphery of the attachment member in the first modification. Note that the same components as those described in the above-described embodiment are denoted by the same reference numerals, and redundant description is omitted.

  As shown in FIG. 13, in the attachment member 6 </ b> A of the first modification, the main body 61 </ b> A includes a second groove 612 and a first wall 615. The second groove 612 is an annular groove provided on the outer peripheral surface of the main body 61A. The second groove 612 is located closer to the passenger compartment than the first groove 611. The first wall 615 is located between the first groove 611 and the second groove 612. The first wall 615 separates the first groove 611 and the second groove 612. The second fitting portion 26 is fitted in the second groove 612.

  As shown in FIG. 13, the first groove 611 and the second groove 612 overlap the band 7A in the radial direction. For example, the sum of the length L611 of the first groove 611 and the length L615 of the first wall portion 615 in the axial direction is smaller than the length L7A of the band 7A in the axial direction. In the radial direction, both ends of the first groove 611 in the axial direction overlap the band 7A. For this reason, the first fitting portion 22 is easily pressed against the inner wall of the first groove 611. In the radial direction, one end of the second groove 612 in the axial direction overlaps the band 7A. For this reason, the second fitting portion 26 is easily pressed against the inner wall of the second groove 612. As a result, the gap between the tubular member 101 and the attachment member 6A is more easily sealed.

  As described above, the attachment member 6A includes the second groove 612, which is an annular groove into which the second fitting portion 26 is fitted, on the outer peripheral surface. As a result, the first fitting portion 22 is hooked on the inner wall of the first groove 611 and the second fitting portion 26 is hooked on the inner wall of the second groove 612. Therefore, the bellows 2 is not detached from the attachment member 6A.

(Second modification)
FIG. 14 is a cross-sectional view of the periphery of the attachment member in the second modification. Note that the same components as those described in the above-described embodiment are denoted by the same reference numerals, and redundant description is omitted.

  As shown in FIG. 14, the bellows 2 </ b> B of the second modified example includes a first protrusion 23. The first protrusion 23 protrudes from the first fitting portion 22 toward the second fitting portion 26.

  As shown in FIG. 14, in the attachment member 6 </ b> B of the second modification, the main body 61 </ b> B includes a second groove 613 and a first wall 616. The second groove 613 is an annular groove provided on the outer peripheral surface of the main body 61B. The second groove 613 is located closer to the passenger compartment than the first groove 611. The first wall 616 is located between the first groove 611 and the second groove 613. The first wall 616 separates the first groove 611 and the second groove 613. The second fitting portion 26 is fitted in the second groove 613. The first protrusion 23 is pressed against the first wall 616.

  As shown in FIG. 14, the first groove 611 and the second groove 613 overlap the band 7B in the radial direction. For example, the sum of the length L611 of the first groove 611 in the axial direction and the length L616 of the first wall portion 616 is smaller than the length L7B of the band 7B in the axial direction. In the radial direction, both axial ends of the first groove 611 overlap the band 7B. For this reason, the first fitting portion 22 is easily pressed against the inner wall of the first groove 611. Further, one end of the second groove 613 in the axial direction overlaps the band 7B in the radial direction. For this reason, the second fitting portion 26 is easily pressed against the inner wall of the second groove 613. As a result, the gap between the tubular member 101 and the attachment member 6B is more easily sealed.

  In the second modified example, the attachment member 6B may not include the second groove 613. In this case, the second fitting portion 26 is fitted into the gap between the first protrusion 23 and the flange portion 62. That is, the position of the inner peripheral surface of the second fitting portion 26 is the same as the position of the inner peripheral surface of the first protrusion 23.

  As described above, the bellows 2B includes the first protrusion 23 that protrudes from the first fitting portion 22 toward the second fitting portion 26. Thereby, the 1st protrusion 23 is pressed on the attachment member 6B with the 1st fitting part 22. FIG. For this reason, the clearance gap between the cylindrical member 101 and the attachment member 6B becomes easier to be sealed.

(Third Modification)
FIG. 15 is a cross-sectional view of the periphery of the attachment member in the third modification. Note that the same components as those described in the above-described embodiment are denoted by the same reference numerals, and redundant description is omitted.

  As shown in FIG. 15, the bellows 2 </ b> C of the third modified example includes a second protrusion 27. The second protrusion 27 protrudes from the second fitting portion 26 toward the side opposite to the first fitting portion 22. That is, the second protrusion 27 protrudes from the second fitting portion 26 toward the flange portion 62 side. The bellows 2C may include the first protrusion 23 shown in the second modification.

  As shown in FIG. 15, in the attachment member 6 </ b> C of the third modified example, the main body portion 61 </ b> C includes a second wall portion 618. The second wall portion 618 is located between the second groove 612 and the flange portion 62. The second wall portion 618 separates the second groove 612 and the flange portion 62.

  As shown in FIG. 15, the first groove 611 and the second groove 612 overlap the band 7C in the radial direction. For example, the sum of the length L611 of the first groove 611 in the axial direction, the length L615 of the first wall portion 615, and the length L612 of the second groove 612 is greater than the length L7C of the band 7C in the axial direction. small. In the radial direction, both ends of the first groove 611 in the axial direction overlap the band 7C. For this reason, the first fitting portion 22 is easily pressed against the inner wall of the first groove 611. Further, both ends of the second groove 612 in the axial direction overlap the band 7C in the radial direction. For this reason, the second fitting portion 26 is easily pressed against the inner wall of the second groove 612. As a result, the gap between the cylindrical member 101 and the attachment member 6C is more easily sealed.

  As described above, the attachment member 6 </ b> C includes the second protrusion 27 that protrudes from the second fitting portion 26 toward the side opposite to the first fitting portion 22. As a result, the second protrusion 27 is pressed against the attachment member 6 </ b> C together with the second fitting portion 26. For this reason, the clearance gap between the cylindrical member 101 and the attachment member 6C becomes easier to seal.

DESCRIPTION OF SYMBOLS 1 Dust cover 10 Dash panel 101 Cylindrical member 102 Slit 11, 12 Seal lip 2, 2B, 2C Bellows 20 Bush fitting part 201 Convex part 21 First flexible part 211 Bending part 22 First fitting part 23 1st protrusion 25 2nd flexible part 26 2nd fitting part 27 2nd protrusion 28, 29 3rd protrusion 5 Bush 50 Base 501 Recess 51 Outer flange 52 Inner flange 59 Lubricant grooves 6, 6A, 6B, 6C Mounting member 61 Main body part 611 First groove 612 Second groove 615 First wall portion 616 First wall portion 62 Flange portions 7, 7A, 7B, 7C Band 80 Steering device 81 Steering wheel 82 First steering shaft 82a Input shaft 82b Output shaft 83 Steering force assist Mechanism 84 First universal joint 85 Second steering shaft 86 Second universal Yointo 87 third steering shaft 88 a steering gear 88a pinion 88b rack 89 tie rod 90 ECU
92 Deceleration device 93 Electric motor 94 Torque sensor 95 Vehicle speed sensor 98 Ignition switch 99 Power supply device Z Rotating shaft

Claims (11)

A bush attached to the outer peripheral surface of the steering shaft that penetrates the cylindrical member of the dash panel;
An annular bellows that closes the gap between the tubular member and the bush;
A cylindrical mounting member that presses the bellows against the cylindrical member;
With
The mounting member includes a first groove which is an annular groove on an outer peripheral surface,
The bellows includes a bush fitting portion that contacts an outer peripheral surface of the bush, a first fitting portion that fits in the first groove, and a first flexible member that connects the bush fitting portion and the first fitting portion. A second fitting portion located on the opposite side of the first flexible portion and in contact with the mounting member, the bush fitting portion and the second fitting portion And a second flexible part that is sandwiched between the tubular member and the first fitting part. The dust cover according to claim 1, wherein the first groove overlaps with an annular band attached to the cylindrical member in a radial direction of the steering shaft. The dust cover according to claim 2, wherein both ends of the first groove in the axial direction of the steering shaft overlap the band in the radial direction. The said attachment member is provided with the main-body part in which the said 1st groove | channel is provided, and the flange part which protrudes toward the outer side of the radial direction of the said steering shaft from the said main-body part. The dust cover described. The dust cover according to any one of claims 1 to 4, wherein the mounting member includes a second groove, which is an annular groove into which the second fitting portion is fitted, on an outer peripheral surface. The dust cover according to any one of claims 1 to 5, wherein the bellows includes a first protrusion that protrudes from the first fitting portion toward the second fitting portion. The dust cover according to claim 1, wherein the bellows includes a second protrusion that protrudes from the second fitting portion toward a side opposite to the first fitting portion. The dust cover according to claim 1, wherein the attachment member is a synthetic resin or an aluminum alloy. A seal lip that closes a gap between the steering shaft and the bush;
The dust cover according to any one of claims 1 to 8, wherein the seal lip is integral with the bush. The dust cover according to any one of claims 1 to 9, wherein the bush fitting portion includes a third protrusion that is deformed by a reaction force from the bush. The recessed part is provided in one of the outer peripheral surface of the said bush, and the inner peripheral surface of the said bush fitting part, and the convex part which fits into the said recessed part is provided in the other. Dust cover.

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