JP2018162842A - Sealing device and seal member used for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing device which can be easily attached and replaced.SOLUTION: A sealing device includes: an atmosphere side seal member fixed to a structure and slidably brought into contact with a shaft arranged in a shaft hole provided in the structure; and a sealed fluid side seal member arranged closer to an internal space side than the atmosphere side seal member, fixed to the structure, and slidably brought into contact with the shaft. The atmosphere side seal member has a screw portion screwed with a screw portion formed on a cylindrical wall of the structure.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a sealing device used in an apparatus having a shaft that moves relative to a structure, and a seal member used therefor.

  In a device having a reciprocating shaft such as a hydraulic cylinder device and a shock absorber, a sealing device for sealing an annular gap between the reciprocating shaft and the inner surface of the shaft hole is provided.

  As this type of sealing device, for example, a device shown in Patent Document 1 is known. FIG. 14 shows the configuration of the device. As shown in FIG. 14, the sealing device 110 seals a space between the piston rod (reciprocating shaft) 114 disposed inside the cylindrical body 112 and the cylindrical body 112. Used for. The sealing device 110 includes an annular insert metal 116 formed of a metal material, and a rubber seal portion 118 that is in close contact with the insert metal 116. The seal portion 118 comes into contact with the piston rod 114 and slides on the piston rod 114 as the piston rod 114 reciprocates in the vertical direction in the drawing.

  In order to attach the sealing device 110 to the cylindrical body 112, a caulking operation is performed in which the end of the cylindrical body 112 is bent from the state indicated by the phantom line to the state indicated by the solid line.

Japanese Patent Laid-Open No. 2005-144582

  The sealing device is required to be easily attached to a desired location, and to be easily replaced when the sealing device is deteriorated.

  Therefore, an object of the present invention is to provide a sealing device that can be easily attached and replaced, and a seal member used therefor.

  In order to solve the above problems, a sealing device according to a first aspect of the present invention is provided between a shaft hole provided in a structure and a shaft that is disposed in the shaft hole and moves relative to the structure. A sealing device that seals an internal space communicating with the shaft hole of the structure, the atmosphere-side seal portion fixed to the structure and slidably contacting the shaft, and the atmosphere A sealed fluid-side seal portion that is disposed closer to the internal space than the side seal portion, is fixed to the structure, and is slidably in contact with the shaft. A screw portion that is screwed into a screw portion formed on the cylindrical wall portion is provided.

  In this sealing device, the atmosphere side seal portion has a screw portion that is screwed into a screw portion formed on the cylindrical wall portion of the structure. When the atmosphere-side seal portion is fixed to the structure, screwing of these screw portions is used. By loosening these screw portions, the atmosphere side seal portion can be removed from the structure. Therefore, the sealing device can be easily attached and replaced.

  Preferably, the atmosphere side seal portion and the sealed fluid side seal portion are an atmosphere side seal member and a sealed fluid side seal member which are separate from each other. Since the atmosphere side seal portion and the sealed fluid side seal portion are separate members, these members can be attached to the structure at different times. It is easy to attach the side seal member to the structure without being restricted by the attitude of the atmosphere side seal member. Moreover, when any one of these deteriorates, it is possible to replace the deteriorated one. In addition, it is evaluated whether at least one of the atmosphere side seal member and the sealed fluid side seal member is appropriate for the use situation, and depending on the result of the evaluation, either one may be replaced with another type of seal member. It is possible to exchange.

  Preferably, the atmosphere-side seal portion has an end wall that contacts a cylindrical end portion of the structure, and an outer cylinder portion that covers an outer peripheral surface of the structure. A female screw portion that is screwed into a male screw portion formed on the outer peripheral surface of the cylindrical wall portion of the structure is formed on the peripheral surface. In this case, an end wall in which the atmosphere-side seal portion disposed on the atmosphere side of the sealed fluid-side seal portion contacts the cylindrical end of the structure, and an outer cylinder portion that covers the outer peripheral surface of the structure, Therefore, even if the fluid sealed from the inner space side of the structure passes through the sealed fluid side seal portion, the atmosphere side seal portion can prevent or reduce the leakage of the fluid to the atmosphere side. it can. Therefore, compared with the case where the atmosphere side seal portion is arranged inside the structure, the performance of sealing the fluid is high.

  Preferably, the atmosphere-side seal portion includes an outer portion formed of a rigid body, and an inner portion formed of an elastic body and disposed inside the outer portion and integrally fixed to the outer portion, The screw portion of the atmosphere side seal portion is formed on the outer portion. In this case, the threaded portion is formed on the outer portion formed of a rigid body, whereby the robustness of the threaded portion can be ensured, and the life of the threaded portion and thus the atmosphere side seal portion can be increased.

  Preferably, the outer portion has an end wall that contacts a cylindrical end of the structure, and an outer cylinder that covers an outer peripheral surface of the structure, and an inner peripheral surface of the outer cylinder In addition, a female screw portion that is screwed into a male screw portion formed on the outer peripheral surface of the cylindrical wall portion of the structure is formed. In this case, the outer wall formed of a rigid body of the atmosphere-side seal portion disposed on the atmosphere side with respect to the sealed fluid-side seal portion is in contact with the cylindrical end of the structure, and the structure Since the fluid sealed from the inner space side of the structure passes through the sealed fluid side seal portion, the fluid side leaks out to the atmosphere side. The seal portion can be prevented or reduced. Therefore, compared with the case where the atmosphere side seal portion is arranged inside the structure, the performance of sealing the fluid is high.

  One sealing member according to the present invention is the atmosphere-side sealing member used in the above-described sealing device. Another sealing member according to the present invention is the sealed fluid side sealing member used in the sealing device.

  The sealing device according to the second aspect of the present invention is disposed between a shaft hole provided in a structure and a shaft that is disposed in the shaft hole and moves relative to the structure. A sealing device for sealing an internal space communicating with the shaft hole of an object, the seal member being disposed inside the shaft hole and slidably contacting the shaft, and disposed closer to the atmosphere than the seal member And a fixing member that is fixed to the structure and prevents the seal member from slipping out of the shaft hole. The fixing member is formed on a screw portion formed on a cylindrical wall portion of the structure. It has a screw part to be screwed.

  In this sealing device, the fixing member that prevents the seal member from coming out of the shaft hole has a screw portion that is screwed into a screw portion formed on the cylindrical wall portion of the structure. When the sealing member is fixed to the structure, the sealing member is inserted into the shaft hole, and then the screw portion of the fixing member and the screw portion of the structure are screwed together. By loosening these screw portions, the fixing member and the seal member can be removed from the structure. Therefore, the sealing device can be easily attached and replaced.

  Preferably, the seal member includes an atmosphere side seal member and a sealed fluid side seal member which are separate from each other. Since the atmosphere side seal member and the sealed fluid side seal member are separate members, when one of them is deteriorated, the deteriorated one can be replaced. In addition, it is evaluated whether at least one of the atmosphere side seal member and the sealed fluid side seal member is appropriate for the use situation, and depending on the result of the evaluation, either one may be replaced with another type of seal member. It is possible to exchange.

  In the atmosphere side aspect of the present invention, when the atmosphere side seal portion is fixed to the structure, screwing of the screw portion of the atmosphere side seal portion and the screw portion of the structure is utilized. By loosening these screw portions, the atmosphere side seal portion can be removed from the structure. Therefore, the sealing device can be easily attached and replaced.

  In the 2nd aspect of this invention, the fixing member which prevents that a sealing member slips out from the inside of a shaft hole has a screw part screwed together by the screw part formed in the cylindrical wall part of a structure. When the sealing member is fixed to the structure, the sealing member is inserted into the shaft hole, and then the screw portion of the fixing member and the screw portion of the structure are screwed together. By loosening these screw portions, the fixing member and the seal member can be removed from the structure. Therefore, the sealing device can be easily attached and replaced.

It is sectional drawing of the sealing device which concerns on 1st Embodiment of this invention. FIG. 2 is a view taken in the direction of arrows II in FIG. 1. It is sectional drawing of the sealing device which concerns on 2nd Embodiment of this invention. It is sectional drawing of the sealing device which concerns on 3rd Embodiment of this invention. It is sectional drawing of the sealing device which concerns on 4th Embodiment of this invention. It is sectional drawing of the sealing device which concerns on 5th Embodiment of this invention. It is sectional drawing of the sealing device which concerns on 6th Embodiment of this invention. It is sectional drawing of the sealing device which concerns on 7th Embodiment of this invention. It is sectional drawing of the sealing device which concerns on 8th Embodiment of this invention. It is sectional drawing of the sealing device which concerns on 9th Embodiment of this invention. It is sectional drawing of the sealing device which concerns on 10th Embodiment of this invention. It is sectional drawing of the sealing device which concerns on 11th Embodiment of this invention. It is sectional drawing of the sealing device which concerns on 12th Embodiment of this invention. It is sectional drawing of the conventional sealing device.

Hereinafter, various embodiments according to the present invention will be described with reference to the accompanying drawings.
First embodiment

  FIG. 1 is a diagram according to the first embodiment of the present invention and shows a main part of a sealing device provided in a shock absorber as an example of a device having a reciprocating shaft.

  The sealing device 1 seals the space between the reciprocating shaft 4 and the inner surface of the shaft hole 8 of the cylinder (structure) 6 of the shock absorber into which the reciprocating shaft 4 is inserted and disposed. This prevents or reduces fluid leakage to the side. The reciprocating shaft 4 of the shock absorber is cylindrical, the cylinder 6 is cylindrical, and the sealing device 1 is substantially annular. However, in FIG. 1, the shock absorber and the sealing device 1 except for the reciprocating shaft 4. Only the left half is shown. FIG. 1 shows a common central axis C of the shock absorber and the sealing device 1.

  The sealing device 1 is an assembly that is a combination including an atmosphere side seal member 10 and a sealed fluid side seal member 20. The atmosphere side seal member 10 and the sealed fluid side seal member 20 are separate members separable from each other. The atmosphere-side seal member 10 is fixed to the cylindrical body 6 and slidably contacts the reciprocating shaft 4. The sealed fluid-side seal member 20 is disposed closer to the inner space than the atmosphere-side seal member 10, is fixed to the cylindrical body 6, and slidably contacts the reciprocating shaft 4. The atmosphere side seal member 10 and the sealed fluid side seal member 20 cooperate to seal the fluid in the internal space. However, the sealed fluid side sealing member 20 mainly seals the fluid in the internal space, whereas the atmospheric side sealing member 10 mainly prevents the entry of foreign matter such as muddy water and dust from the atmospheric side into the internal space. To do.

  The atmosphere-side sealing member 10 has an inner portion 12 that is an elastic ring formed of an elastic body, for example, an elastomer, and an outer portion 14 that is formed of a rigid body, for example, a metal. The outer portion 14 is a reinforcing ring that is disposed outside the inner portion 12 and reinforces the inner portion 12. That is, the atmosphere-side sealing member 10 has a composite structure including the inner portion 12 and the outer portion 14. The inner portion 12 is integrally fixed to the inner edge portion of the end wall 14 a of the outer portion 14.

  The outer portion 14 has a substantially L-shaped cross section. The outer portion 14 connects the end wall 14a, which is a flat plate extending in a plane perpendicular to the central axis C, the outer cylindrical portion 14b covering the outer peripheral surface of the cylindrical body 6, and the outer edge portion of the end wall 14a and the outer cylindrical portion 14b. It has a curved portion 14c. The end wall 14 a comes into contact with the upper end portion of the cylindrical body 6. On the inner peripheral surface of the outer cylindrical portion 14b, a female screw portion 18 is formed which is screwed into the male screw portion 7 formed on the outer peripheral surface of the upper end portion of the cylindrical body 6. When the atmosphere-side seal member 10 is fixed to the cylindrical body 6, the screwing of these screw portions 7 and 18 is used. The air-side seal member 10 can be removed from the cylindrical body 6 by loosening these screw portions 7 and 18.

  The inner portion 12 has two dust strips 16a and 16b protruding radially inward. The dust strips 16 a and 16 b are protrusions that are continuous in the circumferential direction, and contact the reciprocating shaft 4. When the reciprocating shaft 4 reciprocates along the direction of the central axis C, the reciprocating shaft 4 slides with respect to the dust strips 16a and 16b, and the contact state between the dust strips 16a and 16b and the reciprocating shaft 4 is maintained. Is done.

  The sealed fluid side seal member 20 also has a composite structure, and includes an elastic ring 22 formed of an elastic body, for example, an elastomer, and a reinforcing ring 24 formed of a rigid body, for example, a metal. The reinforcing ring 24 is a flat ring and reinforces the elastic ring 22. The reinforcing ring 24 is embedded in the elastic ring 22 and is integrally fixed to the elastic ring 22. Therefore, the elastic ring 22 is arranged not only on the inner peripheral side of the reinforcing ring 24 but also on the outer peripheral side of the elastic ring 22. The sealed fluid side seal member 20 is press-fitted (ie, an interference fit) inside the cylinder 6, and a portion of the elastic ring 22 outside the reinforcing ring 24 is formed on the inner peripheral surface of the cylinder 6. In a pressed state, the sealed fluid side seal member 20 is fixed to the cylindrical body 6.

  The elastic ring 22 includes an outer annular body 22A that contacts the inner peripheral surface of the cylindrical body 6, an inner annular body 22C that is disposed near the reciprocating shaft 4, and an intermediate annular body that is disposed between the annular bodies 22A and 22C. And a body 22B. The inner annular body 22C has two seal lips 26a and 26b protruding radially inward. The seal lips 26 a and 26 b are protrusions that are continuous in the circumferential direction, and contact the reciprocating shaft 4. When the reciprocating shaft 4 reciprocates along the direction of the central axis C, the reciprocating shaft 4 slides against the seal lips 26a and 26b, and the contact state between the seal lips 26a and 26b and the reciprocating shaft 4 is maintained. Is done. A garter spring 28 for compressing the inner annular body 22C radially inward is wound around the inner annular body 22C.

  The seal lips 26a and 26b mainly serve to seal the fluid in the internal space of the cylindrical body 6. The garter spring 28 gives the seal lips 26a, 26b a force for pressing the seal lips 26a, 26b against the reciprocating shaft 4. The dust strips 16a and 16b mainly serve to prevent foreign matter from entering from the atmosphere side to the internal space side.

  The shock absorber is provided with a guide 30 for the reciprocating shaft 4. The guide 30 is disposed inside the cylindrical body 6 and is fixed to the cylindrical body 6. A reciprocating shaft 4 is inserted into a center hole 31 formed in the guide 30. The reciprocating shaft 4 is guided by the center hole 31 and can reciprocate in the vertical direction in the figure.

  An annular protrusion 32 is formed on the upper surface of the guide 30. The protrusion 32 is fitted in the space between the outer annular body 22A and the intermediate annular body 22B of the sealed fluid side seal member 20. When the sealing device 1 is attached to the shock absorber, the movement of the atmosphere side seal member 10 in the vertical direction is restricted by the screwing of the screw portions 7 and 18. The fluid-side seal member 20 is restricted from moving upward by the atmosphere-side seal member 10, and is restricted from moving downward by the protrusion 32 of the guide 30.

  When the female thread portion 18 of the atmosphere side seal member 10 is screwed into the male thread portion 7 of the cylindrical body 6 and when the screw engagement is released, the operator holds the atmosphere side seal member 10 with the center axis C by hand or a tool. Just rotate around. In order to facilitate the rotation of the atmosphere-side seal member 10, as shown in FIG. 2, the outer cylindrical portion 14b of the outer portion 14 of the atmosphere-side seal member 10 is formed to have a hexagonal outline similar to the nut. It is preferable.

  In the sealing device 1, when the atmosphere-side seal portion 10 is fixed to the cylindrical body 6, screwing of the screw portions 7 and 18 is used. The atmosphere side seal member 10 can be removed from the cylindrical body 6 by loosening the screw portions 7 and 18. Therefore, the sealing device 1 can be easily attached and replaced. When the use conditions are severe and the life of the sealing device 1 is short, the sealing device 1 can be easily replaced.

  Although not shown, in the sealing device 1, the atmosphere-side seal member 10 and the sealed fluid-side seal member 20 can be integrally formed. That is, the rigid outer portion 14 and the reinforcing ring 24 may be integrally formed, and the elastic inner portion 12 and the elastic ring 22 may be integrally formed. Even in this case, the sealing device can be attached to the cylindrical body 6 by press-fitting the elastic ring 22 into the shaft hole 8 of the cylindrical body 6 while screwing the female threaded portion 18 into the male threaded portion 7 of the cylindrical body 6. . Further, the sealing device can be removed from the cylindrical body 6 by the reverse operation.

  On the other hand, in the sealing device 1 according to this embodiment, since the atmosphere-side seal member 10 and the sealed fluid-side seal member 20 are separate members, these members can be attached to the cylindrical body 6 at different times. Since it is possible, it is easy to mount the sealed fluid side seal member 20 arranged on the inner space side to the cylinder body 6 without being restricted by the attitude of the atmosphere side seal member 10. Moreover, when any one of these deteriorates, it is possible to replace the deteriorated one. In an environment where there are many foreign substances, when the life of the sealed fluid side seal member 20 is shorter than the life of the atmosphere side seal member 10, only the sealed fluid side seal member 20 can be replaced. Further, it is evaluated whether at least one of the atmosphere-side seal member 10 and the sealed fluid-side seal member 20 is appropriate for the use situation, and depending on the result of the evaluation, either one of the seals is another type of seal. It can be exchanged for a member.

  When the sealed fluid side seal member 20 is fixed to the cylindrical body 6, the sealed fluid side seal member 20 is press-fitted into the cylindrical body 6. By extracting the sealed fluid side seal member 20 from the cylindrical body 6, the sealed fluid side seal member 20 can be detached from the cylindrical body 6. Therefore, attachment and replacement of the sealing device 1 are further facilitated.

  The atmosphere-side sealing member 10 has an end wall 14a that comes into contact with the end portion of the cylindrical body 6 and an outer cylindrical portion 14b that covers the outer peripheral surface of the cylindrical body 6, and on the inner peripheral surface of the outer cylindrical portion 14b, A female screw portion 18 is formed which is screwed into the male screw portion 7 formed on the outer peripheral surface of the cylindrical body 6. Therefore, even if the fluid sealed from the inner space side of the cylindrical body 6 passes through the sealed fluid side seal member 20, the atmosphere side seal member 10 prevents or reduces the leakage of the fluid to the atmosphere side. Can do. Therefore, the performance of sealing the fluid is higher than that in a ninth embodiment (FIG. 10), which will be described later, in which the atmosphere-side sealing member is disposed inside the cylinder 6.

Second Embodiment FIG. 3 shows a sealing device 40 according to a second embodiment of the present invention. In FIG. 3 and the subsequent drawings, the same reference numerals are used to show the components common to the other embodiments, and the components will not be described in detail.

  As shown in FIG. 3, in the sealing device 40 according to the second embodiment of the present invention, the atmosphere-side sealing member 10 has an inner portion 12A different from the inner portion 12 of FIG. 1 (first embodiment). The inner portion 12A has a single dust lip 16c, and a garter spring 17 is wound around the inner portion 12A to compress the dust lip 16c radially inward.

  When the reciprocating shaft 4 reciprocates along the direction of the central axis C, the reciprocating shaft 4 slides with respect to the dust lip 16c, and the contact state between the dust lip 16c and the reciprocating shaft 4 is maintained. The garter spring 17 ensures that the dust lip 16c contacts the reciprocating shaft 4 over a wide area. Accordingly, the inner portion 12A has a higher function of preventing the entry of foreign matter from the atmosphere side to the inner space side than the inner portion 12 of FIG. 1 (first embodiment).

  This embodiment has the same effect as the first embodiment.

  Further, as apparent from comparison between FIG. 1 and FIG. 3, when the atmosphere side seal member 10 of FIG. 1 (first embodiment) is replaced with the atmosphere side seal member 10 of FIG. 3, FIG. 3 (second embodiment). The sealing device 40 is completed. In addition to the atmosphere-side seal member 10 being easily removable from the cylindrical body 6, the atmosphere-side seal member 10 and the sealed fluid-side seal member 20 are separate members. It is easy to modify the sealing device 40 of the second embodiment. For example, it is possible to evaluate whether or not the atmosphere-side seal member 10 is appropriate for the use situation, and depending on the result of the evaluation, the atmosphere-side seal member 10 can be replaced with another type of atmosphere-side seal member 10. is there.

Third Embodiment FIG. 4 shows a sealing device 41 according to a third embodiment of the present invention. As shown in FIG. 4, in the sealing device 41 according to the third embodiment of the present invention, the sealed fluid side seal member 20 has an elastic ring 42 different from the elastic ring 22 of FIG. 3 (second embodiment). Have. The inner annular body 22C of the elastic ring 42 has a single seal lip 46, and the garter spring 28 (see FIG. 1) is not wound around the inner annular body 22C.

  When the reciprocating shaft 4 reciprocates along the direction of the central axis C, the reciprocating shaft 4 slides with respect to the seal lip 46 and the contact state between the seal lip 46 and the reciprocating shaft 4 is maintained. Due to the absence of the garter spring 28, the elastic ring 42 is less worn than the elastic ring 22 of FIG. 1 (first embodiment). Furthermore, since the seal lip 46 is single, the frictional force applied to the reciprocating shaft 4 by the elastic ring 42 is small.

  This embodiment has the same effect as the first embodiment.

  Further, as apparent from comparison between FIG. 1 and FIG. 4, when the sealed fluid side seal member 20 of FIG. 1 (first embodiment) is replaced with the sealed fluid side seal member 20 of FIG. The sealing device 41 of the third embodiment is completed. In addition to the atmosphere-side seal member 10 being easily removable from the cylindrical body 6, the atmosphere-side seal member 10 and the sealed fluid-side seal member 20 are separate members. It is easy to modify the sealing device 41 of the third embodiment. For example, it is evaluated whether or not the sealed fluid side seal member 20 is appropriate for the use situation. Depending on the result of the evaluation, the sealed fluid side seal member 20 may be replaced with another type of sealed fluid side seal member 20. It is possible to exchange.

Fourth Embodiment FIG. 5 shows a sealing device 43 according to a fourth embodiment of the present invention. As is apparent from a comparison of FIGS. 3 to 5, the sealing device 43 according to the fourth embodiment of the present invention is similar to the atmosphere-side sealing member 10 of FIG. 3 (second embodiment) and FIG. 4 (third embodiment). ) To be sealed fluid side seal member 20.

  This embodiment has the same effect as the first embodiment.

  Further, when the sealed fluid side seal member 20 of FIG. 3 (second embodiment) is replaced with the sealed fluid side seal member 20 of FIG. 5, the sealing device 43 of FIG. 5 (fourth embodiment) is completed. When the atmosphere-side sealing member 10 in FIG. 4 (third embodiment) is replaced with the atmosphere-side sealing member 10 in FIG. 5, the sealing device 43 in FIG. 5 (fourth embodiment) is completed. In addition to the atmosphere-side seal member 10 being easily removable from the cylindrical body 6, the atmosphere-side seal member 10 and the sealed fluid-side seal member 20 are separate members. It is easy to modify the sealing device of the embodiment.

Fifth Embodiment FIG. 6 shows a sealing device 51 according to a fifth embodiment of the present invention. The sealing device 51 includes a screw 52 as a loosening prevention mechanism for the atmosphere side seal member 10 and the cylindrical body 6. A through hole is formed in the outer cylinder portion 14 b of the outer portion 14 of the atmosphere side seal member 10, and a screw hole that does not penetrate the cylinder body 6 is formed in the outer peripheral surface of the cylinder body 6. The screw 52 is passed through the through hole of the outer cylinder portion 14 b and is screwed into the screw hole of the cylinder body 6. The number of screws 52 is not limited.

  Even in an environment with a lot of vibrations, such a loosening prevention mechanism can keep the outer cylinder portion 14b and the cylinder body 6 screwed together, and thus the sealing device 51 and the cylinder body 6 can be kept fixed. By loosening the screw 52, the sealing device 51 can be easily detached from the cylinder 6.

  Although this embodiment is an improvement of FIG. 1 (first embodiment), a similar locking mechanism may be provided in other embodiments.

Sixth Embodiment FIG. 7 shows a sealing device 55 according to a sixth embodiment of the present invention. The sealing device 55 has a nut 57 as a mechanism for preventing the air-side sealing member 10 and the cylinder 6 from loosening. The length of the male thread portion 7 on the outer peripheral surface of the cylindrical body 6 is considerably larger than the length of the female thread portion 18 of the outer cylindrical portion 14b of the outer portion 14 of the atmosphere side seal member 10. Before attaching the atmosphere side seal member 10 to the cylindrical body 6, the nut 57 is screwed into the male screw portion 7 on the outer peripheral surface of the cylindrical body 6. Due to the principle of the double nut mechanism comprising the female thread portion 18 and the nut 57 of the outer cylinder portion 14b, the effect of preventing loosening is exhibited. The nut 57 may be a normal nut or a hard lock nut.

  Even in an environment with a lot of vibrations, such a loosening prevention mechanism can keep the outer cylinder portion 14b and the cylinder body 6 screwed together, and thus the sealing device 55 and the cylinder body 6 can be fixed.

  Although this embodiment is an improvement of FIG. 1 (first embodiment), a similar locking mechanism may be provided in other embodiments. A washer may be used as the locking mechanism.

Seventh Embodiment FIG. 8 shows a sealing device 61 according to a seventh embodiment of the present invention. The sealing device 61 is provided with a mechanism for preventing relative movement between the atmosphere side seal member 10 and the sealed fluid side seal member 20. In the illustrated example, the relative movement preventing mechanism is a protrusion 64 formed on the outer portion 14 of the atmosphere-side seal member 10 and a recess 62 formed on the reinforcing ring 24 of the sealed fluid-side seal member 20. Is fitted into the recess 62. The number of protrusions 64 and recesses 62 is not limited. A recess may be formed in the outer portion 14 of the atmosphere-side seal member 10, and a protrusion may be formed in the reinforcing ring 24 of the sealed fluid-side seal member 20. Although this embodiment is an improvement of FIG. 1 (first embodiment), a similar relative movement prevention mechanism may be provided in other embodiments.

Eighth Embodiment FIG. 9 shows a sealing device 65 according to an eighth embodiment of the present invention. The sealing device 65 is provided with a relative movement preventing mechanism between the atmosphere side seal member 10 and the sealed fluid side seal member 20. In the illustrated example, the relative movement preventing mechanism is a screw 67. A through hole is formed in the end wall 14 a of the outer portion 14 of the atmosphere-side seal member 10, and a screw hole that does not penetrate the reinforcement ring 24 is formed in the reinforcement ring 24 of the sealed fluid-side seal member 20. The screw 67 is passed through the through hole of the end wall 14 a and is screwed into the screw hole of the reinforcing ring 24. The number of screws 57 is not limited. Although this embodiment is an improvement of FIG. 1 (first embodiment), a similar relative movement prevention mechanism may be provided in other embodiments.

Ninth Embodiment FIG. 10 shows a sealing device 71 according to a ninth embodiment of the present invention. In this sealing device 71, the atmosphere-side sealing member 10 has an outer portion 74 different from the outer portion 14 of FIG. 1 (first embodiment). The outer portion 74 formed of a rigid body has an end wall 74a that is a flat plate extending in a plane perpendicular to the central axis C, an outer cylinder portion 74b that extends downward from the end wall 74a, and an outer edge portion 74c that extends outward from the end wall 74a. Have The inner portion 12 formed of an elastic body is integrally fixed to the inner edge portion of the end wall 74 a of the outer portion 74.

  On the outer peripheral surface of the outer cylinder portion 74b, a male screw portion 78A that is screwed into the female screw portion 7A formed on the inner peripheral surface of the upper end portion of the cylindrical body 6 is formed. When the atmosphere-side seal member 10 is fixed to the cylindrical body 6, the screwing of these screw portions 7A and 78A is used. The atmosphere side seal member 10 can be removed from the cylindrical body 6 by loosening the screwing of these screw portions 7A, 78A. Therefore, the sealing device 1 can be easily attached and replaced.

  When the male screw portion 78A of the atmosphere-side seal member 10 is screwed into the female screw portion 7A of the cylindrical body 6 and when the screwing is released, the operator holds the atmosphere-side seal member 10 with the center axis C by hand or a tool. Just rotate around. In order to facilitate rotation of the atmosphere-side seal member 10, it is preferable to form the outer edge portion 74c of the outer portion 74 of the atmosphere-side seal member 10 so as to have a hexagonal outline similar to that of the hexagon nut.

  In the sealing device 71, since the atmosphere side seal portion 10 and the sealed fluid side seal portion 20 are separate members, these members can be attached to the cylindrical body 6 at different times. It is easy to mount the sealed fluid-side seal member 20 disposed on the space side to the cylindrical body 6 without being restricted by the attitude of the atmosphere-side seal member 10. Moreover, when any one of these deteriorates, it is possible to replace the deteriorated one. Further, it is evaluated whether at least one of the atmosphere-side seal member 10 and the sealed fluid-side seal member 20 is appropriate for the use situation, and depending on the result of the evaluation, either one of the seals is another type of seal. It can be exchanged for a member. Other types of seal members are not shown but will be readily understood by those skilled in the art.

  When the sealed fluid side seal member 20 is fixed to the cylindrical body 6, the sealed fluid side seal member 20 is press-fitted into the cylindrical body 6. By extracting the sealed fluid side seal member 20 from the cylindrical body 6, the sealed fluid side seal member 20 can be detached from the cylindrical body 6. Therefore, attachment and replacement of the sealing device 71 are further facilitated.

Tenth Embodiment FIG. 11 shows a sealing device 81 according to a tenth embodiment of the present invention. The sealing device 81 is disposed inside the shaft hole 8 of the cylindrical body 6 and is disposed on the atmosphere side of the seal member 82 and a seal member 82 that is slidably in contact with the reciprocating shaft 4. And a fixing member 83 that prevents the hole 8 from slipping out.

  Unlike the above-described embodiment shown in FIGS. 1 to 10, the seal member 82 is not a plurality of parts that can be easily separated, but is a single member. However, the seal member 82 has a composite structure including an elastic ring 84 formed of an elastic body, for example, an elastomer, and a reinforcing ring 85 formed of a rigid body, for example, a metal. The reinforcing ring 85 is a flat ring and reinforces the elastic ring 84. The reinforcing ring 85 is embedded in the elastic ring 84 and is integrally fixed to the elastic ring 84. Therefore, the elastic ring 84 is arranged not only on the inner peripheral side of the reinforcing ring 85 but also on the outer peripheral side of the elastic ring 84. The seal member 82 is press-fitted into the inner peripheral surface of the cylindrical body 6 (that is, an interference fit), and a portion of the elastic ring 84 outside the reinforcing ring 85 is pressed against the inner peripheral surface of the cylindrical body 6. In this state, the seal member 82 is fixed to the cylindrical body 6.

  The elastic ring 84 includes an outer annular body 22A that contacts the inner peripheral surface of the cylindrical body 6, an inner annular body 22C that is disposed near the reciprocating shaft 4, and an intermediate annular body that is disposed between the annular bodies 22A and 22C. And a body 22B. The inner annular body 22 </ b> C has a single sealing lip 86 that contacts the reciprocating shaft 4. When the reciprocating shaft 4 reciprocates along the direction of the central axis C, the reciprocating shaft 4 slides with respect to the seal lip 86 and the contact state between the seal lip 86 and the reciprocating shaft 4 is maintained. A garter spring 28 for compressing the inner annular body 22C radially inward is wound around the inner annular body 22C.

  The inner annular body 22C extends to the atmosphere side with respect to the reinforcing ring 85, and has a single dust lip 87 protruding to the atmosphere side. The dust lip 87 is a protrusion that is continuous in the circumferential direction, and contacts the reciprocating shaft 4. When the reciprocating shaft 4 reciprocates along the direction of the central axis C, the reciprocating shaft 4 slides with respect to the dust lip 87, and the contact state between the dust lip 87 and the reciprocating shaft 4 is maintained.

  The seal lip 86 mainly serves to seal the fluid in the internal space of the cylindrical body 6. The garter spring 28 applies a force to the seal lip 86 to press the seal lip 86 against the reciprocating shaft 4. The dust lip 87 mainly plays a role of preventing entry of foreign matter from the atmosphere side to the internal space side.

  The fixing member 83 is formed of a rigid body, for example, metal. It has an end wall 83a that is a flat plate extending in a plane orthogonal to the central axis C, an outer cylinder part 83b that covers the outer peripheral surface of the cylindrical body 6, and a curved part 83c that connects the outer edge part of the end wall 83a and the outer cylinder part 83b. . The end wall 83a is formed with a through hole 83d in which the reciprocating shaft 4 and the dust lip 87 are disposed.

  On the inner peripheral surface of the outer cylindrical portion 83b of the fixing member 83, a female screw portion 88 is formed that is screwed into the male screw portion 7 formed on the outer peripheral surface of the upper end portion of the cylindrical body 6. When the fixing member 83 is fixed to the cylindrical body 6, the screwing of these screw portions 7 and 88 is used. The fixing member 83 can be removed from the cylindrical body 6 by loosening the screwing of these screw portions 7 and 88.

  The fixing member 83 is provided with an annular ridge 83e that contacts the seal member 82 in order to prevent the seal member 82 from coming out of the shaft hole of the cylindrical body 6. The protrusion 83e is formed on the surface of the end wall 83a on the inner space side, and contacts the reinforcing ring 85 of the seal member 82.

  The shock absorber is provided with a guide 30 for the reciprocating shaft 4. The guide 30 is disposed inside the cylindrical body 6 and is fixed to the cylindrical body 6. A reciprocating shaft 4 is inserted into a center hole 31 formed in the guide 30. The reciprocating shaft 4 is guided by the center hole 31 and can reciprocate in the vertical direction in the figure.

  An annular protrusion 32 is formed on the upper surface of the guide 30. The protrusion 32 is fitted in the space between the outer annular body 22A and the intermediate annular body 22B of the seal member 82. When the sealing device 81 is attached to the shock absorber, the fixing member 83 is restricted from moving in the vertical direction by screwing the screw portions 7 and 88. The seal member 82 is restricted from moving upward by the fixing member 83 and is restricted from moving downward by the protrusion 32 of the guide 30.

  When the female screw portion 88 of the fixing member 83 is screwed into the male screw portion 7 of the cylindrical body 6 and when the screwing is released, the operator rotates the fixing member 83 around the central axis C by hand or a tool. You can do it. In order to facilitate the rotation of the fixing member 83, it is preferable to form the outer cylinder portion 83b of the fixing member 83 so as to have a hexagonal outline similar to the hexagon nut.

  In the sealing device 81, a fixing member 83 that prevents the seal member 82 from coming out of the inside of the shaft hole 8 of the cylindrical body 6 has a female thread portion 88 that is screwed into the male thread portion 7 formed in the cylindrical body 6. . When the seal member 82 is fixed to the cylinder body 6, the seal member 82 is inserted into the shaft hole 8, that is, press-fitted, and then the female screw portion 88 of the fixing member 83 and the male screw portion 7 of the cylinder body 6 are screwed together. By loosening the screw portions 7 and 88, the fixing member 83 can be removed from the cylindrical body 6, and the sealing member 82 is removed from the inner peripheral surface of the cylindrical body 6 to thereby remove the sealing member 82 from the cylindrical body 6. It can be removed from the body 6. Therefore, the sealing device 81 can be easily attached and replaced. When the use conditions are severe and the life of the sealing device 81 is short, the sealing device 81 can be easily replaced.

Eleventh Embodiment FIG. 12 shows a sealing device 91 according to an eleventh embodiment of the present invention. This embodiment is an improvement of the sealing device 81 of FIG. 11 (tenth embodiment), and the seal member 82 includes an atmosphere side seal member 92 and a sealed fluid side seal member 94 that are separate from each other. It can be considered that the seal member 82 of this embodiment is a plane perpendicular to the central axis C, and the seal member 82 of the tenth embodiment is cut.

  The atmosphere-side sealing member 92 has a composite structure including an inner portion 93 which is an elastic body, for example, an elastic ring made of an elastomer, and an outer portion 85A made of a rigid body, for example, metal. The outer portion 85A is a flat ring and reinforces the inner portion 93. The inner portion 93 is integrally fixed to the inner edge portion of the outer portion 85A. A dust lip 87 is provided in the inner portion 93.

  The sealed fluid side seal member 94 also has a composite structure, and includes an elastic ring 95 formed of an elastic body, for example, an elastomer, and a reinforcing ring 85B formed of a rigid body, for example, a metal. The reinforcing ring 85B is a flat ring and reinforces the elastic ring 95. The reinforcing ring 85B is embedded in the elastic ring 95 and is integrally fixed to the elastic ring 95. A seal lip 86 is provided on the elastic ring 95.

  Both the atmosphere-side seal member 92 and the sealed fluid-side seal member 94 are press-fitted (ie, interference fit) into the cylindrical body 6. In this embodiment, since the atmosphere-side seal member 92 and the sealed fluid-side seal member 94 are separate members, when one of them deteriorates, the deteriorated one can be replaced. Further, it is evaluated whether at least one of the atmosphere-side seal member 92 and the sealed fluid-side seal member 94 is appropriate for the use situation, and depending on the result of the evaluation, either one of the seals is another type of seal. It can be exchanged for a member.

Twelfth Embodiment FIG. 13 shows a sealing device 101 according to a twelfth embodiment of the present invention. The sealing device 101 includes a fixing member 104 different from the fixing member 83 of FIG. 11 (tenth embodiment). The fixing member 104 formed of a rigid body includes an end wall 104a that is a flat plate extending in a plane perpendicular to the central axis C, a protrusion 104b that protrudes downward from the end wall 104a, and an outer edge portion 104c that extends outward from the end wall 104a. Have The end wall 104a is formed with a through hole 104d in which the reciprocating shaft 4 and the dust lip 87 are disposed.

  On the outer peripheral surface of the protrusion 104b, a male screw portion 108 is formed which is screwed into the female screw portion 7A formed on the inner peripheral surface of the upper end portion of the cylindrical body 6. When the fixing member 104 is fixed to the cylindrical body 6, screwing of these screw portions 7A and 108 is used. The fixing member 104 can be removed from the cylindrical body 6 by loosening the screwing of these screw portions 7A and 108.

  In addition, the fixing member 104 is provided with an annular protrusion 104b that contacts the seal member 82 in order to prevent the seal member 82 from coming out of the shaft hole of the cylindrical body 6. The ridge 104 b is formed on the surface of the end wall 104 a on the inner space side, and contacts the reinforcing ring 85 of the seal member 82.

  When the sealing device 101 is attached to the shock absorber, the fixing member 104 is restricted from moving in the vertical direction by screwing of the screw portions 7A and 108. The seal member 82 is restricted from moving upward by the fixing member 104 and is restricted from moving downward by the protrusion 32 of the guide 30.

  When the male screw portion 108 of the fixing member 104 is screwed into the female screw portion 7A of the cylindrical body 6 and when the screwing is released, the operator rotates the fixing member 104 around the central axis C by hand or a tool. You can do it. In order to facilitate the rotation of the fixing member 104, the outer edge portion 104c of the fixing member 104 is preferably formed to have a hexagonal outline similar to the hexagon nut.

  In the sealing device 101, the fixing member 104 that prevents the seal member 82 from coming out of the shaft hole 8 of the cylindrical body 6 has a male screw portion 108 that is screwed into the female screw portion 7 </ b> A formed in the cylindrical body 6. . When the seal member 82 is fixed to the cylinder 6, the seal member 82 is inserted into the shaft hole 8, that is, press-fitted, and then the male screw portion 108 of the fixing member 104 and the female screw portion 7 A of the cylinder 6 are screwed together. By loosening these screw portions 7A and 108, the fixing member 104 can be removed from the cylindrical body 6. Further, by removing the sealing member 82 from the inner peripheral surface of the cylindrical body 6, the sealing member 82 is removed from the cylindrical body 6. It can be removed from the body 6. Therefore, the sealing device 101 can be easily attached and replaced. When the use conditions are severe and the life of the sealing device 101 is short, the sealing device 101 can be easily replaced.

  The seal member 82 of the twelfth embodiment is not a plurality of parts that can be easily separated, but is a single member. However, like the seal member 82 of the eleventh embodiment, the seal member 82 may be composed of a separate atmospheric-side seal member and sealed fluid-side seal member. In this case, when any one of these deteriorates, it is possible to replace the deteriorated one. In addition, it is evaluated whether at least one of the atmosphere side seal member and the sealed fluid side seal member is appropriate for the use situation, and depending on the result of the evaluation, either one may be replaced with another type of seal member. It is possible to exchange.

  Although various embodiments of the present invention have been described above, the above description is not intended to limit the present invention, and various modifications including deletion, addition, and replacement of components are included in the technical scope of the present invention. Conceivable.

  For example, although the above embodiment is used for a shock absorber having the reciprocating shaft 4, the application of the present invention is not limited to the shock absorber, and may be used for other devices. Moreover, the sealing device according to the present invention is not limited to a device having a reciprocating shaft that reciprocally moves relative to the structure, and may be used for a device that has a shaft that rotates relative to the structure. That is, this invention relates to the sealing device used for the apparatus which has the axis | shaft which moves relatively to a structure, and the sealing member used for this.

  The sealing device according to the above embodiment has at least one sealing lip and at least one dust lip. The sealing device may have a lip for other purposes.

  In the ninth embodiment (FIG. 10), the locking mechanism described with respect to the fifth embodiment (FIG. 6) and the sixth embodiment (FIG. 7) is used to maintain the fixed state between the outer portion 74 and the cylindrical body 6. It may be provided. In the tenth to twelfth embodiments (FIGS. 11 to 13), the locking mechanism described with respect to the fifth and sixth embodiments is provided to maintain the fixed state of the fixing member 83 or 104 and the cylindrical body 6. May be. Further, in the ninth embodiment and the eleventh embodiment, the relative movement preventing mechanism described with respect to the seventh embodiment (FIG. 8) and the eighth embodiment (FIG. 9) is replaced with the atmosphere side seal member 10 or 92 and the sealed fluid. It may be provided to prevent relative movement of the side seal member 20 or 94.

1, 40, 41, 43, 51, 61, 65, 71, 81, 91, 101 Sealing device 4 Reciprocating shaft (axis)
6 cylinder (structure)
7 Male thread part 7A Female thread part 8 Shaft hole 10 Air side seal member (atmosphere side seal part)
12, 12A Inner portion 14, 74 Outer portion 14a End wall 14b Outer tube portion 14c Curved portion 16a, 16b, 16c Dustrip 17 Garter spring 18 Female thread portion 20 Sealed fluid side seal member (sealed fluid side seal portion)
22, 42 Elastic ring 22A Outer ring body 22B Intermediate ring body 22C Inner ring body 24 Reinforcement rings 26a, 26b, 46 Seal lip 28 Garter spring 30 Guide 32 Projection 31 Center hole 52 Screw 57 Nut 64 Projection 62 Recess 67 Screw 74a End Wall 74b Outer cylinder part 74c Outer edge part 78A Male thread part 82 Seal member 83 Fixing member 83a End wall 83b Outer cylinder part 83c Curved part 83d Through hole 83e Projection 84 Elastic ring 85 Reinforcement ring 85A Outer part 85B Reinforcement ring 86 Seal lip 87 Strip 88 Female thread portion 92 Atmosphere side seal member 94 Sealed fluid side seal member 93 Inner portion 95 Elastic ring 104 Fixing member 104a End wall 104b Projection 104c Outer edge portion 104d Through hole 108 Male thread portion

Claims (9)

A shaft hole provided in the structure and a shaft disposed in the shaft hole and moving relative to the structure are arranged to seal an internal space communicating with the shaft hole of the structure. A sealing device,
An atmospheric seal portion fixed to the structure and slidably contacting the shaft;
A sealed fluid side seal portion that is disposed closer to the internal space than the atmosphere side seal portion, is fixed to the structure, and slidably contacts the shaft;
The sealing device according to claim 1, wherein the atmosphere-side seal portion includes a screw portion that is screwed into a screw portion formed on a cylindrical wall portion of the structure. 2. The sealing device according to claim 1, wherein the atmosphere side seal portion and the sealed fluid side seal portion are an atmosphere side seal member and a sealed fluid side seal member which are separate from each other. The atmosphere side seal portion has an end wall that contacts the cylindrical end of the structure, and an outer cylinder that covers the outer peripheral surface of the structure,
The female thread part screwed together with the external thread part formed in the outer peripheral surface of the said cylindrical wall part of the said structure is formed in the internal peripheral surface of the said outer cylinder part, The Claim 1 or 2 characterized by the above-mentioned. The sealing device according to 1. The atmosphere side seal portion includes an outer portion formed of a rigid body, and an inner portion formed of an elastic body and disposed inside the outer portion and integrally fixed to the outer portion,
The sealing device according to claim 1 or 2, wherein the screw portion of the atmosphere side seal portion is formed on the outer portion. The outer portion has an end wall that contacts the cylindrical end of the structure, and an outer cylinder that covers the outer peripheral surface of the structure,
The female thread part screwed together with the male thread part formed in the outer peripheral surface of the said cylindrical wall part of the said structure is formed in the internal peripheral surface of the said outer cylinder part, The Claim 4 characterized by the above-mentioned. Sealing device.   The atmosphere side sealing member used for the sealing device according to claim 2.   The sealed fluid side seal member used in the sealing device according to claim 2. A shaft hole provided in the structure and a shaft disposed in the shaft hole and moving relative to the structure are arranged to seal an internal space communicating with the shaft hole of the structure. A sealing device,
A seal member disposed inside the shaft hole and slidably contacting the shaft;
A fixing member disposed on the atmosphere side of the seal member, fixed to the structure, and preventing the seal member from slipping out of the shaft hole;
The sealing device according to claim 1, wherein the fixing member has a screw portion that is screwed into a screw portion formed on a cylindrical wall portion of the structure. The sealing device according to claim 8, wherein the seal member includes a separate atmospheric-side seal member and a sealed fluid-side seal member.

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