Dust cover and shock absorber

Abstract

The invention provides a dust cover for suppressing deviation of a belt and a shock absorber with the dust cover. A second end portion connected with the other axial end side of the cylindrical portion and a third end portion connected with one axial end side of the cylindrical portion are formed on one end side fixing portion of the dust cover, and a belt is wound between the second end portion and the third end portion which protrude towards the radial outer side, so that axial deviation of the belt can be restrained. One end side fixing part of the dust cover can be prevented from falling off from the belt fastening part of the flange part.

Description

Technical Field

[0001] This invention relates to dust covers and shock absorbers. Background Technology

[0002] Patent document 1 discloses a shock absorber 1 whose rod-side fixing part 32 of the dust cover 41 is fixed to the outer periphery 26 of the rod cover 25 by a strap 34.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2019-132295 Summary of the Invention

[0006] The technical problem that the invention aims to solve

[0007] However, in the aforementioned buffer, when the rod cover is removed, a dust cover is needed to cover the piston rod. In this case, a strap is used to fix the rod-side fixing part (one-end fixing part) of the dust cover to the flange fixed at the front end (one-end end) of the piston rod. However, because the width (short axial length) of the strap fastening part on the radially outer side of the flange is narrow, the strap may shift axially.

[0008] The objective of this invention is to provide a dust cover for suppressing belt deflection and a buffer having the dust cover.

[0009] Technical solutions for solving technical problems

[0010] The dust cover of the present invention is characterized by comprising: a corrugated portion having a peak and a valley; a first wall portion connected to a first end portion formed on one axial end of the corrugated portion, extending from the radially inward side to the radially outward side; a cylindrical portion connected to a second end portion formed on the radially outward side of the first wall portion, having a recessed portion that is at least partially recessed radially inward side; a second wall portion connected to a third end portion formed on one axial end of the cylindrical portion, extending from the radially outward side to the radially inward side; and an inclined portion connected to a fourth end portion formed on the radially inward side of the second wall portion, extending inclinedly from the radially inward side to the radially outward side.

[0011] The buffer of the present invention is characterized in that the dust cover has: a corrugated portion having a peak and a valley; a first wall portion connected to a first end portion formed on one axial end of the corrugated portion, formed to extend radially inward to radially outward, and abutting against a first abutting surface on the other axial end of the flange portion; a cylindrical portion connected to a second end portion formed on the radially outward end of the first wall portion, forming a recess that is at least a portion recessed radially inward in the natural state, and abutting against the radially outward side of the flange portion; a second wall portion connected to a third end portion formed on one axial end of the cylindrical portion, formed to extend radially inward to radially outward, and abutting against a second abutting surface on one axial end of the flange portion; an inclined portion connected to a fourth end portion formed on the radially inward end of the second wall portion, formed to extend inclinedly from radially inward to radially outward, and the band is disposed on the radially outward side of the cylindrical portion.

[0012] According to one embodiment of the present invention, a dust cover that suppresses belt deviation and a buffer having the dust cover can be provided.

[0013] Translation of attached images

[0014] Figure 1 This is a cross-sectional view of the axial plane of the buffer in this embodiment.

[0015] Figure 2 This is an explanatory diagram of this embodiment, which is an enlarged cross-section based on the axial plane showing the radially outer end of the fixing part and the flange part of the dust cover in its natural state before tightening.

[0016] Figure 3 yes Figure 1 An enlarged view of part A in the image. Detailed Implementation

[0017] An embodiment of the present invention will be described with reference to the accompanying drawings.

[0018] Here, an example is a multi-cylinder, transversely mounted, single-flow hydraulic buffer 1 (hereinafter referred to as "buffer 1") installed as a yaw damper between the bodies of a railway vehicle. For convenience, Figure 1 The left side of the middle is called the axial end side. Figure 1 The right side of the axis is called the other end side of the axis. Figure 2 The upper side of the middle is called the radial outer side, which will Figure 2 The lower side of the middle is called the radial inner side.

[0019] like Figure 1As shown, the buffer 1 has a cylinder 2 with an inner cylinder 3 and an outer cylinder 4 coaxially arranged. The buffer 1 has an annular reservoir 5 formed between the inner cylinder 3 and the outer cylinder 4 of the cylinder 2. The buffer 1 has a closing member 6 that closes one axial end of the inner cylinder 3 and the outer cylinder 4. The closing member 6 functions as a rod guide for guiding the piston rod 10. The buffer 1 has a closing member 7 that closes the other axial end of the inner cylinder 3 and the outer cylinder 4. The closing member 7 has a closing portion 8 that closes the other axial end of the inner cylinder 3 and a closing portion 9 that closes the other axial end of the outer cylinder 4.

[0020] A piston 13 is inserted inside the inner cylinder 3, dividing the interior of the inner cylinder 3 into a first chamber 11 on one axial end and a second chamber 12 on the other axial end. The end of the piston rod 10 on the other axial end is fixed to the piston 13. The piston rod 10 extends through the sealing member 6 and outwards from the cylinder 2. A buffer 1 is provided on the sealing member 7, having a passage 18 that connects the second chamber 12 and the reservoir 5. A check valve 19 is provided in the passage 18, allowing only the working fluid to flow from the reservoir 5 to the second chamber 12.

[0021] The buffer 1 has a check valve 14 disposed on the piston 13, which allows the working fluid to flow only from the second chamber 12 to the first chamber 11. The buffer 1 is disposed on the sealing member 6, having a passage 15 connecting the first chamber 11 and the reservoir 5. The buffer 1 has a valve mechanism 16 disposed on the passage 15 for regulating the flow of the working fluid from the first chamber 11 to the reservoir 5. Furthermore, the first chamber 11 and the second chamber 12 are sealed with working fluid as the working fluid. Additionally, the reservoir 5 is sealed with both working fluid and gas as the working fluid.

[0022] The buffer 1 has a mounting ring 21 fixed to the closure 9 and connected to one side of the railway vehicle body. A pin 23 is mounted to the mounting ring 21 via a bushing 22. On the other hand, the buffer 1 has a flange 31 fixed to the front end (one end) of the piston rod 10. The buffer 1 has a mounting ring 25 fixed to the flange 31 and the piston rod 10 and connected to the other side of the railway vehicle body. A pin 27 is mounted to the mounting ring 25 via a bushing 26.

[0023] The buffer 1 has a dust cover 41 that covers the piston rod 10 protruding from the self-sealing component 6. The dust cover 41 has: a corrugated portion 42 with alternating peaks 43 and valleys 44 along the axial direction; a one-end fixing portion 51 connected to one end of the corrugated portion 42; and a other-end fixing portion 45 connected to the other end of the corrugated portion 42 along the axial direction. The one-end fixing portion 51 is fixed by a belt fastening portion 33 (outer cylindrical surface) formed on the radially outer end 32 (thin-walled portion) of the flange portion 31 by a belt 52. On the other hand, the other-end fixing portion 45 is fixed by a belt 46 to the outer peripheral surface 17 of one end of the outer cylinder 4. In addition, the dust cover 41 is a resin molded part.

[0024] like Figure 2 As shown, the one-end fixing portion 51 has a first end portion 53 formed on the axial one-end end (valve portion 44) of the corrugated portion 42. The one-end fixing portion 51 has a first wall portion 54 connected to the first end portion 53 and formed in a manner extending radially outward from the first end portion 53 (radially inward). When the first wall portion 54 is fastened to the flange portion 31 by the strap 52 (hereinafter referred to as the "installed state") (see reference 51), the first wall portion 54 is... Figure 3 It abuts against the first abutting surface 34 of the flange portion 31. The first abutting surface 34 is formed on the end face of the radially outer end 32 of the flange portion 31 on the other end side of the axial direction.

[0025] One end fixing portion 51 has a second end portion 55 formed at the radially outer end of the first wall portion 54. When the dust cover 41 is in its natural state (a state without external force, hereinafter referred to as "natural state"), the first wall portion 54 is located at the first end portion 53 on the axially opposite side compared to the second end portion 55. Figure 2 The position of the "right side" in the text is tilted. The radial length of the first wall portion 54 is shorter than the radial length from the peak portion 43 to the valley portion 44 of the corrugated portion 42.

[0026] One end fixing portion 51 is connected to the second end portion 55, and has a cylindrical portion 56 formed in such a way that it extends from the second end portion 55 (the other axial end side) toward the axial end side. The cylindrical portion 56 has, in its natural state (refer to...), Figure 2 The recess 57 is recessed radially inward from the axial center. On the other hand, the cylindrical portion 56 abuts against the fastening portion 33 of the flange portion 31 in the installed state. Furthermore, in... Figure 2 In the middle, the cylindrical part 56 is concave throughout the entire length of the terrain, but it is possible to form a concave part 57 by only making the central part of the axis concave inward in the radial direction.

[0027] One-end fixing portion 51 has a third end portion 58 formed at one end of the cylindrical portion 57. The third end portion 58 and the second end portion 55 are formed to protrude radially outward relative to the cylindrical portion 56. In other words, the second end portion 55 and the third end portion 58 have an outer diameter larger than that of the cylindrical portion 56. One-end fixing portion 51 is connected to the third end portion 58 and has a second wall portion 59 formed in a manner that extends radially inward from the third end portion 58 (radially outward). In other words, one-end fixing portion 51 has a first wall portion 54 extending radially inward from the other end portion (second end portion 55) of the cylindrical portion 56 and a second wall portion 59 extending radially inward from one end portion (third end portion 58) of the cylindrical portion 56.

[0028] When the second wall portion 59 is in the installation state (see reference) Figure 3 The first abutment surface 34 abuts against the second contact surface 35 of the flange portion 31. The second contact surface 35 is formed on the end face of the radially outer end 32 of the flange portion 31 on one axial end side. The second contact surface 35 is disposed on a plane perpendicular to the axis of the dust cover 41 (hereinafter referred to as the "axial right-angle plane"). Here, the first contact surface 34 is disposed on the axial right-angle plane. In addition, the flange portion 31 has a thick-walled portion 38, and the end face 36 on one axial end side of the thick-walled portion 38 is inclined relative to the axial right-angle plane in such a way that the wall thickness becomes thinner from the radially inner side to the radially outer side (the axial length becomes shorter). As a result, an annular step portion 37 is formed between the second contact surface 35 of the flange portion 31 and the end face 36 on one axial end side.

[0029] The one-end fixing portion 51 has a fourth end portion 60 formed at the radially inner end of the second wall portion 59. In its natural state, the second wall portion 59 has the fourth end portion 60 located axially closer to one end than the third end portion 58. Figure 2 The position of the "left side" in the text is tilted. In the natural state, the axial distance between the first end 53 and the fourth end 60 of the one-end fixing part 51 is longer than the axial distance between the second end 55 and the third end 58. In other words, the one-end fixing part 51 is formed such that in the natural state, the first wall part 54 and the second wall part 59 open radially inward.

[0030] One end fixing portion 51 is connected to the fourth end portion 60 and has an inclined portion 61 formed in a manner extending radially outward from the fourth end portion 60. The inclined portion 61 is inclined away from the second wall portion 59 as it moves radially inward toward radially outward. The one end fixing portion 51 has a slit 62 extending radially inward with a constant width from the radially outward end of the inclined portion 61 (the open end of the one end fixing portion 51). Thus, when the dust cover 41 is installed, the one end fixing portion 51 can open the slit 62 to expand the diameter of the open end. Furthermore, multiple slits 62 can be formed in the one end fixing portion 51.

[0031] Next, the steps for installing the dust cover 41 onto the main body of the buffer 1 will be described.

[0032] First, insert the main body of the buffer 1 into the opening of the fixing part 51 at one end of the dust cover 41 from the side where the mounting ring 21 is located. At this time, by opening the cut-out part 62 to enlarge the opening end of the fixing part 51, the pin 23 installed on the mounting ring 21 can be easily inserted into the dust cover 41.

[0033] Next, the main body of the buffer 1 protrudes from the other end fixing part 45 of the dust cover 41. Thus, the other end fixing part 45 of the dust cover 41 fits into the outer peripheral surface 17 of the outer cylinder 4. Next, the other end fixing part 45 of the dust cover 41 is axially positioned relative to the outer cylinder 4, and the strap 46 wound around the outer periphery of the other end fixing part 45 of the dust cover 41 is tightened. Thus, the other end fixing part 45 is pressed radially inward and tightened to the axial end of the outer cylinder 4. Furthermore, the timing of tightening the strap 46 can be appropriate; for example, it can be done when tightening the axial end strap 52.

[0034] Next, as Figure 2 As shown, the flange 31 of the main body of the buffer 1 is inserted into the opening of the end-side fixing part 51 of the dust cover 41. In this embodiment, by opening the cut-out part 62 to enlarge the diameter of the opening end of the end-side fixing part 51, the flange 31 can be easily inserted into the end-side fixing part 51.

[0035] Next, the dust cover 41 is fixed at one end 51 relative to the flange 31 in the axial direction ( Figure 2 Positioned in the "left and right directions" (as in the original text). In this embodiment, as... Figure 2 As shown, the cylindrical portion 56 of the one-end fixing portion 51 is positioned opposite the fastening portion 33 of the flange portion 31 so that their axial centers are aligned. Furthermore, in this embodiment, the radially outer end 32 of the flange portion 31 is inserted between the first wall portion 54 and the second wall portion 59 of the one-end fixing portion 51, thus allowing for easy axial positioning of the one-end fixing portion 51 relative to the flange portion 31.

[0036] Next, a tape 52 is wound around the outer periphery of the one-end fixing portion 51 of the dust cover 41. In this embodiment, the tape 52 is wound between the second end 55 and the third end 58 of the one-end fixing portion 51, which protrude radially outward from the cylindrical portion 56. Therefore, the tape 52 can be easily positioned axially relative to the one-end fixing portion 51 of the dust cover 41 and the tape fastening portion 33 of the buffer 1 body. Next, the tape 52 wound around the outer periphery of the one-end fixing portion 51 of the dust cover 41 is fastened. As a result, the cylindrical portion 56 of the one-end fixing portion 51 is pressed radially inward and fastened to the tape fastening portion 33 of the flange portion 31.

[0037] The result is, as Figure 3 As shown, the two axial ends of the cylindrical portion 56 of the one-end fixing portion 51 are tightly fitted with the fastening portion 33 (outer cylindrical surface) of the flange portion 31, thus eliminating the recess 57 and making it flat along the entire axial length. As a result, the first wall portion 54 of the one-end fixing portion 51 is pressed against the first abutment surface 34 of the flange portion 31, such that the second end portion 55 is located on the axial side further away than the first end portion 53. In other words, the first end portion 53 is inclined relative to the right-angle plane of the axis in such a way that the first end portion 53 enters the first abutment surface 34 side more than the second end portion 55.

[0038] On the other hand, the second wall portion 59 of the one-end fixing portion 51 is pressed against the second abutment surface 35 of the flange portion 31, such that the third end portion 58 is located on the axial side closer to the fourth end portion 60; in other words, the fourth end portion 60 is inclined relative to the axial right-angle plane such that the fourth end portion 60 enters the second abutment surface 35 side more than the third end portion 58. In this way, the radially outer end portion 32 of the flange portion 31 is held axially by a pair of wall portions 54, 59 by the elastic force generated by the material of the dust cover 41. Moreover, in this embodiment, the second wall portion 59 is inclined in a way that enters the other axial side, so that the fourth end portion 60 of the one-end fixing portion 51 can be tightly fitted by biting into the stepped portion 37 of the flange portion 31.

[0039] In conventional dust covers, the limited width (short axial length) of the fastening portion on the flange makes it difficult to position the fixing portion at one end relative to the flange in the axial direction. Furthermore, conventional dust covers lack a structure to suppress belt misalignment, allowing the belt to potentially shift axially relative to the fixing portion at one end and detach from the flange.

[0040] In contrast, in this embodiment, the one-end fixing portion 51 has: a first wall portion 54, which is disposed on the other axial end side of the cylindrical portion 56 and extends radially inward from the second end portion 55; and a second wall portion 59, which is disposed on one axial end side of the cylindrical portion 56 and extends radially inward from the third end portion 58. When the dust cover 41 is installed, the radially outer end portion 32 of the flange portion 31 is inserted between the first wall portion 54 and the second wall portion 59, so that the one-end fixing portion 51 of the dust cover 41 can be easily positioned axially relative to the flange portion 31.

[0041] In this embodiment, a recess 57 is formed in the cylindrical portion 56 of the end-side fixing portion 51, which is axially recessed in the center when in the natural state. Therefore, the axial distance between the first wall portion 54 and the second wall portion 59 can be opened radially inward, and the end portion 32 of the radially outer side of the flange portion 31 can be easily received between the first wall portion 54 and the second wall portion 59.

[0042] In this embodiment, when installed, the cylindrical portion 56 is tightly fitted with the fastening portion 33 of the flange portion 31, and the cylindrical portion 56 becomes flat along its entire axial length. As a result, the first wall portion 54 is pressed against the first abutment surface 34 of the flange portion 31, and the radially inner first end portion 53 is inclined toward the first abutment surface 34 in a manner that is greater than the radially outer second end portion 55. On the other hand, the second wall portion 59 is pressed against the second abutment surface 35 of the flange portion 31, and the fourth end portion 60 is inclined toward the second abutment surface 35 in a manner that is greater than the third end portion 58.

[0043] That is, the elasticity generated by the material of the dust cover 41 allows the radially outer end 32 of the flange 31 to be clamped axially by a pair of wall portions 54, 59, thereby improving the sealing performance of the dust cover 41. Furthermore, in this embodiment, since the fourth end 60 is tightly fitted into the step portion 37 formed on the flange 31, the sealing performance of the dust cover 41 can be further improved.

[0044] In this embodiment, a slit 62 extending radially inward from the opening end (the radially outer end) is formed on the inclined portion 61 of the dust cover 41, which serves as the insertion port of the buffer 1 body. Therefore, by opening the slit 62 to expand the diameter of the inclined portion 61 (the end of one end of the one-side fixing portion 51), the flange portion 31 can be easily inserted into the one-side fixing portion 51 of the dust cover 41, thereby improving the assemblability.

[0045] In this embodiment, a second end 55 that is axially connected to the other end of the cylindrical portion 56 and protrudes radially outward and a third end 58 that is axially connected to one end of the cylindrical portion 56 and protrudes radially outward are formed on one end of the dust cover 41. A belt 52 is wound between the second end 55 and the third end 58, so the belt 52 can be suppressed from axially shifting and the one end of the dust cover 41 can be prevented from falling off the belt fastening portion 33 of the flange portion 31.

[0046] Furthermore, the implementation method is not limited to the above-described manner; for example, it can be configured as follows.

[0047] In this embodiment, the second abutting surface 35 of the flange portion 31 to which the second wall portion 59 of the dust cover 41 abuts is configured to be parallel to the axial right-angle plane of the dust cover 41. In contrast, the second abutting surface 35 can be formed to be inclined relative to the axial right-angle plane in a manner that enters from the radially outer side toward the radially inner side toward the other end side (the side of the first abutting surface 34) in the axial direction.

[0048] In this case, the fourth end 60 of the one-side fixing part 51 can be tightly fitted by being bitten into the step part 37 formed on the flange part 31, which can further improve the sealing performance of the dust cover 41.

[0049] Furthermore, the present invention is not limited to the embodiments described above, and includes various modifications. For example, the embodiments described above are detailed embodiments for the purpose of easily understanding and illustrating the present invention, and are not limited to having all the structures described. In addition, a part of the structure of a certain embodiment can be replaced with the structure of another embodiment, and it is also possible to add the structure of another embodiment to the structure of a certain embodiment. Furthermore, regarding a part of the structure of each embodiment, other structures can be added, deleted, or replaced.

[0050] This application claims priority based on Japanese Patent Application No. 2023-117626, filed on July 19, 2023. The entire disclosure of the specification, claims, drawings, and abstract of Japanese Patent Application No. 2023-117626, filed on July 19, 2023, is incorporated herein by reference in its entirety.

[0051] Explanation of reference numerals in the attached figures

[0052] 1: Buffer

[0053] 41: Dust cover

[0054] 42: Ripples

[0055] 43: Peak

[0056] 44: Tanibe

[0057] 53: First end

[0058] 54: First wall section

[0059] 55: Second end

[0060] 56: Cylindrical part

[0061] 57: concave part

[0062] 58: Third end

[0063] 59: Second wall section

[0064] 60: Fourth end

[0065] 61: Inclined section

Claims

1. A dust cover for use with a buffer, characterized in that, have: The corrugated section has peaks and valleys; The first wall portion is connected to the first end portion formed at one axial end of the corrugated portion, and is formed to extend from the radially inner side to the radially outer side. The cylindrical portion is connected to a second end formed at the radially outer end of the first wall portion, and has a recess that is at least partially recessed radially inward in the axial direction. The second wall portion is connected to the third end portion formed at one axial end of the cylindrical portion, and is formed to extend from the radially outer side to the radially inner side. An inclined portion, which is connected to a fourth end of an end formed on the radially inner side of the second wall portion, is formed to extend inclinedly from the radially inner side to the radially outer side.

2. The dust cover according to claim 1, characterized in that, The second end and the third end have an outer diameter larger than the cylindrical portion.

3. The dust cover according to claim 1 or 2, characterized in that, The first wall portion is inclined such that the first end is located on the axially opposite side compared to the second end. The second wall portion is inclined such that the fourth end is located on the axial side of the third end portion.

4. The dust cover according to claim 1 or 2, characterized in that, The inclined portion has a cutout that extends radially inward from the radially outer end.

5. A buffer comprising: a cylinder sealed with a working fluid; A piston rod, one end of which protrudes from the cylinder; a flange portion, which is located at one end of the piston rod and protrudes radially outward; A dust cover, one end of which is fixed to the flange and the other end of which is fixed to the cylinder; a belt that fixes the dust cover to the flange, characterized in that the dust cover has: The corrugated section has peaks and valleys; The first wall portion is connected to a first end portion formed at one axial end of the corrugated portion, and is formed in such a way that it extends from the radially inner side to the radially outer side, and abuts against a first abutting surface at the other axial end of the flange portion. A cylindrical portion, which is connected to a second end formed at the radially outer end of the first wall portion, forms a recess that is at least a portion of which is radially recessed inward in the natural state, and abuts against the radially outer side of the flange portion. The second wall portion is connected to the third end portion formed at one axial end of the cylindrical portion, and is formed in such a way that it extends from the radially outer side to the radially inner side, and abuts against the second abutting surface at one axial end of the flange portion. An inclined portion, which connects to a fourth end portion formed on the radially inner side of the second wall portion, and is formed in a manner that extends inclinedly from the radially inner side to the radially outer side. The belt is located on the radially outer side of the cylindrical portion.

6. The buffer according to claim 5, characterized in that, The first wall portion is inclined such that the first end is located closer to the first contact surface than the second end.

7. The buffer according to claim 5 or 6, characterized in that, The second wall portion is inclined such that the fourth end is located closer to the second abutment surface than the third end.

8. The buffer according to claim 5 or 6, characterized in that, The second abutment surface is inclined such that its radially inner side is located at a position relative to the radially outer side on the other end of the axial direction.

9. The buffer according to claim 5 or 6, characterized in that, The flange portion has: a thin-walled portion formed at the radially outer end; a thick-walled portion whose axial length is longer than the thin-walled portion; and an annular stepped portion formed between the thin-walled portion and the thick-walled portion. The fourth end of the dust cover abuts against the stepped portion.

10. The buffer according to claim 5 or 6, characterized in that, The second and third ends of the dust cover have an outer diameter larger than that of the cylindrical portion.

11. The buffer according to claim 5 or 6, characterized in that, The dust cover has a cutout that extends radially inward from the radially outer end of the inclined portion.

Images