WO2022050063A1

WO2022050063A1 - Buffer

Info

Publication number: WO2022050063A1
Application number: PCT/JP2021/030348
Authority: WO
Inventors: 靖春谷津; 智也沼倉; 幹郎山下
Original assignee: 日立Astemo株式会社
Priority date: 2020-09-01
Filing date: 2021-08-19
Publication date: 2022-03-10
Also published as: JPWO2022050063A1

Abstract

A buffer (1) including: an external cylinder (2) and an internal cylinder (5) in which a hydraulic oil is encapsulated; a piston (6) inserted in the internal cylinder and partitioning the internal cylinder into a bottom side oil chamber (B) and a rod side oil chamber (C); a piston rod (7) coupled to the piston and extending out of the external cylinder; a blocking member (11) blocking one end of the external cylinder; a seal member (13) provided in the inner circumferential hole of the blocking member and making sliding contact with the piston rod; and a cover (17) covering the seal member and the piston rod and forming a hydraulic oil storage chamber (18).

Description

Buffer

The present disclosure relates to a shock absorber mounted on a railroad vehicle, for example, and preferably used to cushion the vibration of the vehicle.

Generally, a shock absorber using a hydraulic liquid such as hydraulic oil is provided between each bogie of a railroad vehicle and the vehicle body to cushion the vibration of the railroad vehicle. This type of prior art shock absorber has a cylinder filled with working liquid, a piston that is inserted into the cylinder and divides the inside of the cylinder into one side chamber and the other side chamber, and is connected to the piston to the outside of the cylinder. It includes an extending piston rod, a closing member that closes at least one end of the cylinder, and a sealing member that is provided in an inner peripheral hole of the closing member and slides on the piston rod.

Further, some shock absorbers are provided with a working liquid absorbing portion that absorbs the working liquid leaked from between the piston rod and the sealing member (Patent Document 1). The working liquid absorbing portion is arranged at a position surrounding the sealing member.

Japanese Unexamined Patent Publication No. 2007-13624

When the shock absorber of Patent Document 1 is used in a state where the cylinder or piston rod is extended in the horizontal direction and is laid on its side, a part of the leaked working liquid is absorbed by the working liquid absorbing portion.

Here, an example of the cause of the hydraulic liquid leaking from between the piston rod and the sealing member will be described. First, the sealing member may be damaged and a large amount of working liquid may leak out, which may affect the cushioning performance. On the other hand, the sealing member scrapes off the working liquid adhering to the outer peripheral surface of the piston rod, so that a small amount of working liquid leaks out, but the cushioning performance may not be affected.

However, since the working liquid absorbing unit only absorbs the leaked working liquid, the operator cannot know the total amount of the leaked working liquid. Therefore, when the working liquid leaks from between the piston rod and the seal member, it cannot be determined whether the working liquid has leaked in a large amount or only in a small amount.

For this reason, when a working liquid leaks, it is assumed that a large amount of working liquid leaks even if only a small amount of working liquid that does not affect the buffering performance leaks. The exchange is being carried out. As a result, the shock absorber may be replaced in addition to the regular maintenance, which causes a problem that the running cost increases.

An object of the embodiment of the present invention is to provide a shock absorber capable of eliminating unnecessary replacement work by confirming that the amount of leaked working liquid is small.

In one embodiment of the present invention, a cylinder in which a working liquid is sealed, a piston inserted into the cylinder to divide the inside of the cylinder into one side chamber and another side chamber, and a piston connected to the piston are connected to the cylinder. It surrounds a piston rod extending to the outside, a closing member that closes at least one end of the cylinder, a sealing member provided in an inner peripheral hole of the closing member and sliding with the piston rod, and the sealing member and the piston rod. It also comprises a cover, which forms a working liquid reservoir.

According to one embodiment of the present invention, it is possible to confirm that the amount of the leaked working liquid is small, and it is possible to eliminate unnecessary replacement work and extend the period of use.

It is sectional drawing which shows the shock absorber by 1st Embodiment of this invention. It is sectional drawing which shows the main part of FIG. 1 enlarged. It is sectional drawing which looked at the cover and the like by the 2nd Embodiment of this invention from the same position as FIG. It is sectional drawing which looked at the cover and the like by the 3rd Embodiment of this invention from the same position as FIG. It is sectional drawing which looked at the cover and the like by the 4th Embodiment of this invention from the same position as FIG. It is sectional drawing which shows the cover and the like by the 5th Embodiment of this invention. 6 is a cross-sectional view of a cover, a float, etc. according to a sixth embodiment of the present invention as viewed from the same position as in FIG.

Hereinafter, the case where the shock absorber according to the embodiment of the present invention is applied to a hydraulic shock absorber used for a railway vehicle or the like will be described in detail according to the attached drawings.

1 and 2 show a first embodiment of the present invention. In this first embodiment, a case where the cylinder is stretched from the end face on the opposite piston side of the closing member and the cover is fixed to the stretched portion of the cylinder is illustrated.

In FIG. 1, the hydraulic shock absorber 1 according to the first embodiment is mounted horizontally between, for example, a vehicle body of a railway vehicle and a bogie (neither of them is shown). The hydraulic shock absorber 1 includes an outer cylinder 2, an extension portion 4, an inner cylinder 5, a piston 6, a piston rod 7, a closing member 11, a seal member 13, a cover 17, and a hydraulic oil storage chamber 18, which will be described later. There is. Here, in the first embodiment, since the hydraulic shock absorber 1 is arranged in the horizontal state, the protruding side of the piston rod 7 will be on the left side and the bottom cap 3 side will be on the right side in the state shown in FIG. ..

The outer cylinder 2 constitutes a cylinder together with the inner cylinder 5. The outer cylinder 2 is composed of a cylindrical body extending in the left-right direction, and the right side in the axial direction is closed by the bottom cap 3, and the left side is closed by the closing member 11 or the like described later. A screw portion 2A is provided on the inner circumference on the left side of the outer cylinder 2. The threaded portion 12A of the lock ring 12, which will be described later, is screwed into the threaded portion 2A.

Here, the left end portion of the outer cylinder 2 is provided with an extension portion 4 extending from the left end surface 11C1 of the diameter-reduced cylinder portion 11C, which is the end surface on the opposite piston side of the closing member 11, which will be described later. The stretched portion 4 constitutes a part of the cover 17, which will be described later. The stretched portion 4 is integrally formed on the left side of the outer cylinder 2 as a cylindrical body equivalent to the outer cylinder 2. Further, as shown in FIG. 2, a threaded portion 4A is formed on the inner circumference of the stretched portion 4. The threaded portion 17B of the cover 17 is screwed into the threaded portion 4A. The stretched portion 4 may be provided as a separate member from the outer cylinder 2 and may be integrally fixed to the outer cylinder 2 by means such as welding, screwing, adhesion, and fitting.

The inner cylinder 5 is coaxially arranged inside the outer cylinder 2 and constitutes a cylinder together with the outer cylinder 2. The inner cylinder 5 is filled with hydraulic oil as a hydraulic liquid. Further, the inner cylinder 5 defines an annular reservoir chamber A between the inner cylinder 5 and the outer cylinder 2, and hydraulic oil and gas are mixed and sealed in the reservoir chamber A. The right end side of the inner cylinder 5 is fitted to the base member 9 described later in the axial direction, and the other end side is inserted into the inner peripheral side of the closing member 11 so that the inner cylinder 5 is axially and radially in the outer cylinder 2. Is positioned at.

The piston 6 is formed as a cylindrical body slidably inserted into the inner cylinder 5. The piston 6 divides the inside of the inner cylinder 5 into a bottom side oil chamber B which is one side chamber and a rod side oil chamber C which is another side chamber. Further, the piston 6 is formed with a communication passage 6A that communicates the bottom side oil chamber B and the rod side oil chamber C so as to penetrate in the axial direction.

The right side of the piston rod 7 is connected to the piston 6 in the inner cylinder 5, and the left side in the axial direction extends to the outside of the outer cylinder 2 via the closing member 11, the sealing member 13, and the like. The outer peripheral surface 7A of the piston rod 7 is in sliding contact with the closing member 11 and the sealing member 13.

The first check valve 8 is provided on the left end surface of the piston 6. The first check valve 8 allows hydraulic oil to flow from the bottom side oil chamber B to the rod side oil chamber C via the communication passage 6A, and regulates the reverse flow.

The base member 9 is located inside the outer cylinder 2 and is attached to the center of the bottom cap 3. The base member 9 is formed in a stepped cylindrical shape, and the bottom side oil chamber B in the inner cylinder 5 is closed by fitting the protruding portion on the left side to the right end portion of the inner cylinder 5. Further, the inner peripheral side of the base member 9 is an oil passage 9A. The oil passage 9A is connected to the damping force generation mechanism 16 via a communication pipeline 15 described later.

The second check valve 10 is provided on the base member 9 so as to block the oil passage 9A. The second check valve 10 allows hydraulic oil to flow from the communication line 15 toward the bottom oil chamber B, and regulates the reverse flow.

The closing member 11 is composed of a stepped cylinder provided on the left side of the outer cylinder 2, and closes the left end which is one end of the outer cylinder 2. The closing member 11 constitutes a rod guide that guides the piston rod 7 on the inner peripheral side. The outer peripheral side of the closing member 11 is fitted in the outer cylinder 2, and the left end portion of the inner cylinder 5 is inserted in the right side portion on the inner peripheral side. On the right side of the closing member 11, an oil passage 11A for communicating the communication pipe line 15 and the rod-side oil chamber C is provided.

On the other hand, as shown in FIG. 2, on the left side of the closing member 11, an annular step portion 11B and a cylindrical reduced diameter tubular portion 11C protruding from the inner peripheral side of the step portion 11B to the left side are formed. There is. The inner peripheral side of the reduced diameter cylinder portion 11C is an inner peripheral hole 11D. A seal member 13 described later is inserted into the inner peripheral hole 11D, and a retaining ring 14 described later for retaining the seal member 13 is attached to the left end side of the diameter-reduced cylinder portion 11C. Further, the left end surface 11C1 of the diameter-reduced cylinder portion 11C constitutes the end surface on the opposite piston side of the closing member 11.

The lock ring 12 fixes the closing member 11 in the outer cylinder 2. The lock ring 12 is formed as a ring member that fits between the outer cylinder 2 and the diameter-reduced cylinder portion 11C of the closing member 11. On the outer peripheral side of the lock ring 12, a threaded portion 12A screwed into the threaded portion 2A of the outer cylinder 2 is formed. Further, a plurality of engaging holes 12B (only two are shown) for engaging the rotating tool are formed on the left end surface of the lock ring 12. Then, the lock ring 12 has the stepped portion 11B on the right end surface 12C by screwing the threaded portion 12A on the outer peripheral side to the threaded portion 2A of the outer cylinder 2 with the closing member 11 inserted in the outer cylinder 2. The closing member 11 can be fixed in the outer cylinder 2 by pressing.

The seal member 13 is provided in the inner peripheral hole 11D of the closing member 11. The seal member 13 includes a cylindrical mounting cylinder portion 13A that is inserted into the inner peripheral hole 11D, and a lip portion 13B that is located on the inner peripheral side of the mounting cylinder portion 13A and slides on the outer peripheral surface 7A of the piston rod 7. have. The seal member 13 is fixed to the retaining state by attaching the retaining ring 14 to the diameter-reduced cylinder portion 11C in a state where the mounting cylinder portion 13A is inserted into the inner peripheral hole 11D.

As shown in FIG. 1, the communication pipeline 15 is provided in the reservoir chamber A so as to extend in the axial direction. The communication pipeline 15 extends over the base member 9 and the closing member 11, and communicates the oil passage 9A of the base member 9 and the oil passage 11A of the closing member 11.

The damping force generation mechanism 16 is provided in the oil passage 11A of the closing member 11. The damping force generation mechanism 16 imparts a flow resistance to the hydraulic oil when the hydraulic oil in the rod side oil chamber C flows toward the bottom side oil chamber B through the communication pipeline 15.

Next, the configuration and function of the cover 17, which is a feature of the present embodiment, will be described in detail.

As shown in FIG. 2, the cover 17 is provided so as to surround the seal member 13 and the piston rod 7. The cover 17 is configured to include the stretched portion 4. The cover 17 is made of a flat circular plate, and an opening 17A through which the piston rod 7 is inserted is formed in the center thereof. On the other hand, on the outer periphery of the cover 17, a threaded portion 17B screwed into the threaded portion 4A of the stretched portion 4 is provided.

By attaching the cover 17 to the inner peripheral side of the stretched portion 4, the cover 17 cooperates with the stretched portion 4 to form a hydraulic oil storage chamber 18 as a hydraulic liquid storage chamber between the closing member 11 and the sealing member 13. ing. In the hydraulic oil storage chamber 18, the lip portion 13B scratches the hydraulic oil leaked from between the outer peripheral surface 7A of the piston rod 7 and the lip portion 13B of the seal member 13 (the hydraulic oil adhering to the outer peripheral surface 7A of the piston rod 7). It is an annular space where (including the ones taken) are stored.

Therefore, in the inspection work of the hydraulic shock absorber 1, by removing the cover 17, the total amount of the hydraulic oil accumulated in the hydraulic oil storage chamber 18, that is, the hydraulic oil leaked from between the piston rod 7 and the seal member 13 is measured. You can check.

As shown in FIG. 1, the mounting ring 19 is provided on the bottom cap 3. The mounting ring 20 is provided at the left end of the piston rod 7. One of the mounting ring 19 and the mounting ring 20 is connected to the vehicle body of a railway vehicle or the like, and the other is connected to the bogie. The rod cover 21 is formed as a cylindrical body that covers the exposed portion of the piston rod 7.

Next, an example of the operation and inspection work of the horizontal hydraulic shock absorber 1 attached to the railroad vehicle as described above will be described.

First, when the bogie traveling along the track causes vibration, a vibration damping device including a horizontal hydraulic shock absorber 1 provided between the bogie and the vehicle body is activated, and the hydraulic shock absorber 1 is a piston. The rod 7 is extended and contracted. As a result, the damping force generation mechanism 16 can generate a damping force and suppress the shaking on the vehicle body side.

Here, when the hydraulic shock absorber 1 is operating, the hydraulic oil inside may leak out. This leakage of hydraulic oil generally occurs between the piston rod 7 and the sealing member 13 when the outer cylinder 2 is not damaged. On the other hand, in the case of hydraulic oil leakage that occurs between the piston rod 7 and the seal member 13, a large amount of hydraulic oil leaks due to damage to the seal member 13, and the cushioning performance is affected. Although the sealing member 13 scrapes off the hydraulic oil adhering to the outer peripheral surface 7A of 7, a small amount of the hydraulic oil leaks out, but the cushioning performance may not be affected. However, it is difficult to determine whether a large amount of hydraulic oil has leaked or a small amount has leaked.

However, according to the present embodiment, the outer cylinder 2 is provided with the stretched portion 4 extending from the left end surface 11C1 of the reduced diameter cylinder portion 11C of the closing member 11, and the sealing member 13 is provided in the stretched portion 4. A cover 17 is provided so as to surround the piston rod 7 and the piston rod 7. As a result, the cover 17 cooperates with the extending portion 4 to form a hydraulic oil storage chamber 18 between the closing member 11 and the sealing member 13. All the hydraulic oil leaked from the hydraulic shock absorber 1 can be stored in the hydraulic oil storage chamber 18.

Therefore, in the inspection work of the hydraulic shock absorber 1, the operator prepares a saucer (not shown) under the extension portion 4, and removes the cover 17 from the extension portion 4 to leak into the hydraulic oil storage chamber 18. The total amount of hydraulic oil can be visually confirmed. That is, it is possible to clearly determine whether a large amount of hydraulic oil leaks out and affects the buffering performance, or whether a small amount of hydraulic oil leaks out does not affect the cushioning performance.

As a result, if only a small amount of hydraulic fluid leaks out and the cushioning performance is not affected, the hydraulic shock absorber 1 can be continued to be used. Therefore, unnecessary replacement work of the hydraulic shock absorber 1 is abolished. The running cost can be reduced.

Next, FIG. 3 shows a second embodiment of the present invention. The feature of this embodiment is that the closing member is fixed by a lock ring screwed into the cylinder, and the cover is fixed between the closing member and the lock ring. In the second embodiment, the same components as those in the first embodiment described above are designated by the same reference numerals, and the description thereof will be omitted.

In FIG. 3, the outer cylinder 31 according to the second embodiment is formed of a cylindrical body extending in the left-right direction, like the outer cylinder 2 according to the first embodiment, and has a screw portion 31A on the inner circumference on the left side in the axial direction. Have. However, the outer cylinder 31 according to the second embodiment is different from the outer cylinder 2 according to the first embodiment in that the stretched portion 4 of the first embodiment described above is not provided.

Similar to the closing member 11 according to the first embodiment, the closing member 32 according to the second embodiment is composed of a stepped cylindrical body provided on the left side of the outer cylinder 31, and closes the left end of the outer cylinder 31 and is inner. A rod guide that guides the piston rod 7 on the peripheral side is configured. The closing member 32 includes an oil passage (not shown), a step portion 32A, a diameter reduction cylinder portion 32B, and an inner peripheral hole 32C. The left end surface 32B1 of the reduced diameter cylinder portion 32B constitutes the end surface on the opposite piston side of the closing member 32.

In the closing member 32 according to the second embodiment, the axial length dimension of the diameter-reduced cylinder portion 32B is shorter than the axial length dimension of the diameter-reduced cylinder portion 11C of the closing member 11 according to the first embodiment. It is formed. In this case, the length dimension of the reduced diameter cylinder portion 32B is set so that the length dimension of the mounting cylinder portion 13A of the seal member 13 and the inner peripheral hole 32C in the axial direction are equal to each other.

The lock ring 33 according to the second embodiment is formed as a ring member that fits between the outer cylinder 31 and the reduced diameter cylinder portion 32B of the closing member 32, similarly to the lock ring 12 according to the first embodiment. Further, the lock ring 33 has a screw portion 33A screwed to the screw portion 31A of the outer cylinder 31 on the outer peripheral side, and has a plurality of engagement holes 33B (only two are shown) on the left end surface. Then, the lock ring 33 has the stepped portion 32A on the right end surface 33C by screwing the threaded portion 33A on the outer peripheral side to the threaded portion 31A of the outer cylinder 31 with the closing member 32 inserted in the outer cylinder 31. The closing member 32 can be fixed in the outer cylinder 31 by pressing.

Here, the inner peripheral surface 33D of the lock ring 33 forms a gap between the inner peripheral surface 33D and the reduced diameter cylinder portion 32B in a state where the closing member 32 is fixed in the outer cylinder 31. A large-diameter tubular portion 34A of the cover 34, which will be described later, is arranged in this gap.

The cover 34 according to the second embodiment is provided so as to surround the seal member 13 and the piston rod 7. The cover 34 is configured as a stepped cylinder made of a thin plate made of metal or resin. Specifically, the cover 34 has a large-diameter cylinder portion 34A located on the right side in the axial direction, a step portion 34B extending inward in the radial direction from the left end portion of the large-diameter cylinder portion 34A, and an inner circumference of the step portion 34B. A small diameter cylinder portion 34C extending to the left side from the small diameter cylinder portion 34C, a lid portion 34D extending radially inward from the left end portion of the small diameter cylinder portion 34C, and an opening 34E located in the center of the lid portion 34D through which the piston rod 7 is inserted. It is composed of.

The large-diameter cylinder portion 34A has a diameter dimension that fits outside the reduced-diameter cylinder portion 32B of the closing member 32, and is sandwiched and fixed between the reduced-diameter cylinder portion 32B and the inner peripheral surface 33D of the lock ring 33. .. Further, the step portion 34B extends inward in the radial direction from the inner peripheral hole 32C of the reduced diameter cylinder portion 32B and is in contact with the left end surface 32B1. As a result, the step portion 34B abuts on the mounting cylinder portion 13A of the seal member 13 in a state of being attached to the closing member 32 side, and the seal member 13 is removed. Further, the lid portion 34D closes between the outer peripheral surface 7A of the piston rod 7 and the small diameter cylinder portion 34C.

When the cover 34 is attached to the closing member 32 side, the cover 34 stores hydraulic oil as a working liquid storage chamber between the small diameter tubular portion 34C, the lid portion 34D, the outer peripheral surface 7A of the piston rod 7, and the sealing member 13. It forms a chamber 35. The hydraulic oil storage chamber 35 is an annular space for storing hydraulic oil leaked from between the piston rod 7 and the seal member 13.

Therefore, at the time of inspection work, by loosening the lock ring 33 and removing the cover 34, the total amount of hydraulic oil accumulated in the hydraulic oil storage chamber 35, that is, the total amount of hydraulic oil leaked from between the piston rod 7 and the seal member 13. Can be confirmed.

Thus, even in the second embodiment configured in this way, it is possible to obtain almost the same action and effect as in the above-mentioned first embodiment. In particular, according to the second embodiment, the cover 34 can be easily manufactured by pressing or molding. Further, since the cover 34 can retain the seal member 13, the retaining ring can be omitted.

Next, FIG. 4 shows a third embodiment of the present invention. The feature of this embodiment is that the closing member is fixed by a lock ring screwed into the cylinder, and the cover is fixed between the closing member and the lock ring. In the third embodiment, the same components as those in the second embodiment described above are designated by the same reference numerals, and the description thereof will be omitted.

In FIG. 4, the cover 41 according to the third embodiment includes a large-diameter cylinder portion 41A, a step portion 41B, a small-diameter cylinder portion 41C, a lid portion 41D, and an opening portion 41E, similarly to the cover 34 according to the second embodiment. ing. However, the cover 41 according to the third embodiment is different from the cover 34 according to the second embodiment in that the flange portion 41F is provided at the right end portion of the large diameter tubular portion 41A. Further, the cover 41 forms a hydraulic oil storage chamber 42 as a hydraulic liquid storage chamber between the small diameter tubular portion 41C, the lid portion 41D, the outer peripheral surface 7A of the piston rod 7, and the seal member 13.

The flange portion 41F of the cover 41 is formed as an annular plate extending radially outward from the right end portion of the large diameter tubular portion 41A. The flange portion 41F is sandwiched between the step portion 32A of the closing member 32 and the right end portion 33C of the lock ring 33. As a result, the cover 41 can be mounted at a position surrounding the seal member 13 and the piston rod 7 with high mounting strength.

Thus, even in the third embodiment configured in this way, it is possible to obtain almost the same action and effect as in the above-mentioned second embodiment. In particular, according to the third embodiment, the flange portion 41F can be securely attached by sandwiching the flange portion 41F between the step portion 32A of the closing member 32 and the right end portion 33C of the lock ring 33. Moreover, since the flange portion 41F can prevent the hydraulic oil from leaking from the hydraulic oil storage chamber 42 by increasing the liquidtightness between the cover 41 and the closing member 32, the operator can prevent the hydraulic oil from leaking. The total amount of hydraulic oil leaked to the storage chamber 42 can be accurately grasped.

Next, FIG. 5 shows a fourth embodiment of the present invention. The feature of this embodiment is that the inner diameter portion of the cover is bent toward the piston side in the axial direction. In the fourth embodiment, the same components as those in the second embodiment described above are designated by the same reference numerals, and the description thereof will be omitted.

In FIG. 5, the cover 51 according to the fourth embodiment includes a large diameter cylinder portion 51A, a step portion 51B, a small diameter cylinder portion 51C, a lid portion 51D, and an opening portion 51E, similarly to the cover 34 according to the second embodiment. ing. However, the cover 51 according to the fourth embodiment is different from the cover 34 according to the second embodiment in that the return portion 51F is provided at the opening 51E which is the inner diameter portion of the lid portion 51D. Further, the cover 51 forms a hydraulic oil storage chamber 52 as a hydraulic liquid storage chamber between the small diameter tubular portion 51C, the lid portion 51D, the outer peripheral surface 7A of the piston rod 7, and the seal member 13.

The return portion 51F of the cover 51 is formed as a cylindrical body that is bent and extends from the opening 51E of the lid portion 51D to the piston 6 side (seal member 13 side) in the axial direction. The return portion 51F can prevent the hydraulic oil collected in the hydraulic oil storage chamber 52 from leaking to the outside of the cover 51 without coming into contact with the outer peripheral surface 7A of the piston rod 7.

Thus, even in the fourth embodiment configured in this way, it is possible to obtain substantially the same action and effect as in the above-mentioned second embodiment. In particular, according to the fourth embodiment, the return portion 51F can prevent the hydraulic oil from leaking from the hydraulic oil storage chamber 52, so that the operator can prevent the hydraulic oil leaking from the hydraulic oil storage chamber 52. It is possible to accurately grasp the total amount of oil.

Next, FIG. 6 shows a fifth embodiment of the present invention. The feature of this embodiment is that the cover is formed of a transparent material and a scale indicating the capacity inside the cover is formed. In the fifth embodiment, the hydraulic shock absorber is arranged vertically so that the axes of the cylinder and the piston rod extend in the vertical direction. In this case, the hydraulic shock absorber in the vertical installation state has the same configuration as the hydraulic shock absorber in the horizontal installation state, such as the piston rod, the closing member, and the seal member. The same reference numerals shall be given and the description thereof shall be omitted.

In FIG. 6, the cover 61 according to the fifth embodiment includes a large diameter cylinder portion 61A, a step portion 61B, a small diameter cylinder portion 61C, a lid portion 61D, and an opening portion 61E, similarly to the cover 34 according to the second embodiment. ing. However, the cover 61 according to the fifth embodiment is molded from a transparent material such as acrylic, polyethylene terephthalate, polycarbonate, vinyl chloride, fluororesin, and the like, and the capacity inside the cover 61. It differs from the cover 34 according to the second embodiment in that the scale 61F shown is formed. Further, the cover 61 forms a hydraulic oil storage chamber 62 as a hydraulic liquid storage chamber between the small diameter tubular portion 61C, the lid portion 61D, the outer peripheral surface 7A of the piston rod 7, and the seal member 13.

The scale 61F of the cover 61 is formed at an intermediate position in the vertical direction of the small diameter tubular portion 61C in consideration of the fact that the hydraulic oil collects on the seal member 13 side of the hydraulic oil storage chamber 62. The position of the scale 61F is arranged, for example, at a position indicating the oil level when the total amount of hydraulic oil leaked to the hydraulic oil storage chamber 62 reaches an amount that affects the cushioning performance. Further, a plurality of scales 61F may be provided, and in this case, attention can be given step by step.

Thus, even in the fifth embodiment configured in this way, substantially the same action and effect as in the above-mentioned second embodiment can be obtained. In particular, according to the fifth embodiment, since the cover 61 is made of a transparent material, the amount of leaked hydraulic oil can be visually recognized from the outside without removing the cover 61. Further, since the cover 61 is provided with the scale 61F, it is possible to clarify the criterion for determining whether or not the total amount of the leaked hydraulic oil affects the cushioning performance.

Next, FIG. 7 shows a sixth embodiment of the present invention. A feature of this embodiment is that the cover is molded from a permeable material and has a float inside the cover made of a material that floats on the working liquid. In the sixth embodiment, the hydraulic shock absorber is arranged vertically so that the axes of the cylinder and the piston rod extend in the vertical direction. In this case, the hydraulic shock absorber in the vertical installation state has the same configuration as the hydraulic shock absorber in the horizontal installation state, such as the piston rod, the closing member, and the seal member. The same reference numerals shall be given and the description thereof shall be omitted.

In FIG. 7, the cover 71 according to the sixth embodiment includes a large diameter cylinder portion 71A, a step portion 71B, a small diameter cylinder portion 71C, a lid portion 71D, and an opening portion 71E, similarly to the cover 34 according to the second embodiment. ing. However, the cover 71 according to the sixth embodiment is according to the second embodiment in that the cover 71 according to the second embodiment is molded from a material having permeability, for example, a resin material such as acrylic, polyethylene terephthalate, polycarbonate, vinyl chloride, and fluororesin. It is different from the cover 34. Further, the cover 71 forms a hydraulic oil storage chamber 72 as a hydraulic liquid storage chamber between the small diameter tubular portion 71C, the lid portion 71D, the outer peripheral surface 7A of the piston rod 7, and the seal member 13.

The float 73 is formed of a material that floats on the hydraulic oil inside the cover 71, that is, in the hydraulic oil storage chamber 72. The float 73 is formed of an annular cavity or a resin material that can move up and down along the inner peripheral surface of the small diameter tubular portion 71C. Further, the position of the float 73 can be easily and accurately specified by using a conspicuous color such as red or yellow.

Thus, even in the sixth embodiment configured in this way, it is possible to obtain substantially the same action and effect as in the above-mentioned second embodiment. In particular, according to the fifth embodiment, since the cover 71 is made of a transparent material, the position of the float 73 inside can be visually recognized without removing the cover 71.

In the fourth embodiment, the case where the opening 51E, which is the inner diameter portion of the lid portion 51D of the cover 51, is provided with the return portion 51F by bending it toward the piston 6 side (seal member 13 side) in the axial direction is exemplified. ing. However, the present invention is not limited to this, and is returned to, for example, the cover 17 according to the first embodiment, the cover 41 according to the third embodiment, the cover 61 according to the fifth embodiment, and the cover 71 according to the sixth embodiment. It may be configured to provide a portion.

The fifth embodiment illustrates the case where the cover 61 is molded from a transparent material. However, the present invention is not limited to this, for example, as a configuration in which the cover 17 according to the first embodiment, the cover 41 according to the third embodiment, and the cover 51 according to the fourth embodiment are molded from a material having transparency. May be good.

In the fifth embodiment, the case where the cover 61 is formed of a transparent material and the scale 61F indicating the capacity inside the cover 61 is formed is illustrated. However, the present invention is not limited to this, and for example, the cover 17 according to the first embodiment, the cover 41 according to the third embodiment, and the cover 51 according to the fourth embodiment are molded from a transparent material and are formed. It may be configured to form a scale indicating the capacity inside the cover. Further, a scale may be formed on the cover 71 according to the sixth embodiment.

In the first embodiment, a single rod type hydraulic shock absorber 1 in which a closing member 11 for closing one end of the outer cylinder 2 is provided and the piston rod 7 is projected to one end side via the closing member 11 is exemplified. However, the present invention is not limited to this, and the cover of each embodiment can be applied to a double-rod type hydraulic shock absorber in which closing members are provided at both ends of the outer cylinder and both sides of the piston rod are projected.

In each embodiment, the case where the hydraulic shock absorber 1 is provided in a railroad vehicle has been described as an example. However, the present invention is not limited to this, and for example, a buffer used for a four-wheeled vehicle and a two-wheeled vehicle, a shock absorber used for various mechanical devices including general industrial equipment, a shock absorber used for a building, and the like to be buffered. It can also be applied to various shock absorbers that buffer.

As the shock absorber based on the embodiment described above, for example, the one described below can be considered.

The first aspect of the shock absorber is a cylinder in which a working liquid is sealed, a piston inserted into the cylinder to divide the inside of the cylinder into one side chamber and another side chamber, and the piston connected to the piston. A piston rod extending to the outside of the cylinder, a closing member that closes at least one end of the cylinder, a sealing member provided in an inner peripheral hole of the closing member and sliding with the piston rod, the sealing member, and the piston rod. A cover, which surrounds and forms a working liquid storage chamber, is provided.

As a second aspect, in the first aspect, the cylinder extends from the anti-piston side end surface of the closing member, and the cover is fixed to the cylinder.

As a third aspect, in the first aspect, the closing member is fixed by a lock ring screwed into the cylinder, and the cover is fixed between the closing member and the lock ring. ..

As a fourth aspect, in any one of the first to third aspects, the inner diameter portion of the cover is bent toward the piston side in the axial direction.

As a fifth aspect, in any one of the first to fourth aspects, the cover is molded of a transparent material.

As a sixth aspect, in any one of the first to fourth aspects, the cover is formed of a transparent material and a scale indicating the capacity inside the cover is formed.

As a seventh aspect, in any one of the first to fifth aspects, the cover includes a float made of a material that floats on the working liquid inside the cover.

The present invention is not limited to the above-described embodiment, and includes various modifications. For example, the above-described embodiment has been described in detail in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to the one including all the described configurations. Further, it is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. Further, it is possible to add / delete / replace a part of the configuration of each embodiment with another configuration.

This application claims priority based on Japanese Patent Application No. 2020-146826 filed on September 1, 2020. The entire disclosure, including the specification, claims, drawings, and abstracts of Japanese Patent Application No. 2020-146826 filed September 1, 2020, is incorporated herein by reference in its entirety.

1 Hydraulic shock absorber (buffer) 2, 31 Outer cylinder (cylinder) 4 Extension part 5 Inner cylinder (cylinder) 6 Piston 7

Piston rod

11, 32 Closing member 11C1, 32B1 Left end face (anti-piston side end face) 11D, 32C

Peripheral hole

12, 33 Lock ring 13

Seal member

17, 34, 41, 51, 61, 71

Cover

18, 35, 42, 52, 62, 72 Hydraulic oil storage chamber (working liquid storage chamber) 51E Opening (inner diameter part) 51F return part 61F scale 73 float B bottom side oil chamber (one side chamber) C rod side oil chamber (other side chamber)

Claims

A cylinder filled with working liquid and
A piston that is inserted into the cylinder and divides the inside of the cylinder into a concubine and a concubine.
A piston rod that is connected to the piston and extends to the outside of the cylinder,
A closing member that closes at least one end of the cylinder,
A seal member provided in the inner peripheral hole of the closing member and sliding with the piston rod,
A shock absorber comprising a cover that surrounds the seal member and the piston rod and forms a working liquid reservoir.
In the shock absorber according to claim 1,
The cylinder extends from the opposite end face of the closing member on the anti-piston side.
The cover is a shock absorber fixed to the cylinder.
In the shock absorber according to claim 1,
The closing member is fixed by a lock ring screwed into the cylinder.
The cover is a shock absorber fixed between the closing member and the lock ring.
In the shock absorber according to any one of claims 1 to 3,
The inner diameter portion of the cover is a shock absorber bent toward the piston side in the axial direction.
In the shock absorber according to any one of claims 1 to 4.
The cover is a shock absorber made of a permeable material.
In the shock absorber according to any one of claims 1 to 4.
The cover is a shock absorber formed of a transparent material and having a scale indicating the capacity inside the cover.
In the shock absorber according to any one of claims 1 to 5.
The cover is a shock absorber having a float formed of a material that floats on a working liquid inside the cover.