JP6956595B2 - Buffer - Google Patents

Description

The present invention relates to a shock absorber.

In recent years, an air suspension using a suspension spring as an air spring has been put into practical use for the purpose of further improving ride comfort and adjusting the vehicle height. In such an air suspension, for example, an air chamber is provided around the shock absorber body. A shock absorber in which the shock absorber body and the air spring are integrated has been widely adopted.

On the other hand, the shock absorber body includes an outer shell and a rod inserted into the outer shell. The shock absorbers are the protector attached to the upper end of the outer shell, the piston pipe attached to the tip of the protector, the cylindrical air chamber attached to the rod in the shock absorber body, and the piston pipe and the air chamber. It is equipped with a rolling diaphragm that is bridged over. In addition to the shock absorber body, the shock absorber includes an air spring including an air chamber, a protector, a piston pipe, and a rolling diaphragm, and forms an air chamber around the rod.

Further, the protector has a cylindrical shape and has a bent portion that bends to the inner peripheral side at the upper end and is mounted over the head portion of the outer shell, and the piston pipe is press-fitted to the outer periphery of the tip of the protector. There is. A seal ring is provided at the press-fitting portion between the protector and the piston pipe to keep the space between the protector and the piston pipe airtight and prevent air leakage from the air chamber (see, for example, Patent Document 1). ).

Japanese Unexamined Patent Publication No. 2006-234068

However, since the protector is only covered with the outer shell, there is a risk that the protector will rotate with respect to the outer shell when a force in the circumferential direction is applied. The piston pipe is press-fitted into the protector, but since the protector may rotate with respect to the outer shell, the piston pipe rotates in the circumferential direction with respect to the air chamber and twists the rolling diaphragm. There is a fear. If the piston pipe rotates in the circumferential direction with respect to the air chamber and twists the rolling diaphragm, there arises a problem that unfavorable resistance is generated due to friction or the like when the shock absorber expands and contracts.

Further, since the protector is only covered with the outer shell, there is a risk that the protector will come off from the outer shell when an axial force is applied. If the protector comes off from the outer shell, it is necessary to align the rolling diaphragm so that it will not be twisted when assembling to the vehicle, which complicates the assembling work.

Further, since the seal ring is provided at the portion where the piston pipe is press-fitted into the protector, there is a possibility that the seal ring may be attacked when the piston pipe is press-fitted into the protector.

Therefore, an object of the present invention is to provide a shock absorber that does not damage the seal ring while preventing the piston pipe from coming off and rotating with respect to the outer shell.

In order to achieve the above object, the shock absorber of the present invention is immovably mounted on the outer periphery of the outer shell, the shock absorber body which has a rod and an outer shell and can be expanded and contracted, the air chamber connected to the rod, and the outer shell. An annular mounting member, a cylindrical piston pipe fitted to the outer periphery of the mounting member, a rolling diaphragm bridged between the air chamber and the piston pipe, and a piston pipe mounted on the outer periphery of the mounting member. and the seal ring in close contact with the inner periphery, detent Me to prevent rotation of the seal ring mounting member in the counterforce air chamber side in the circumferential direction of the piston pipe omission and stopper part and the piston pipe to prevent dislodgement against the mounting member It has a department . In the thus configured damper, the seal ring and stopper portion and detent Me portion missing mounting member is provided in the counter-air chamber side, and omission by the mounting member relative to the outer shell of the piston pipe rotation and It is possible to prevent the piston pipe from attacking the seal ring when the piston pipe is attached to the attachment member.

The end inner periphery of the piston pipe may be press-fit portion to be press-fitted in which a detachment preventing Me part and the detent Me part in the counter-air chamber side of the seal ring of the outer periphery of the mounting member. According to the shock absorber configured in this way, by press-fitting the piston pipe into the mounting member, it is possible to prevent the piston pipe from coming off and rotating from the outer shell, and a component is added to prevent the piston pipe from coming off and rotating. Since it is not necessary, the cost is excellent and the assembly work is easy.

Also, movement in the axial direction and the circumferential direction with respect to the hole and the mounting member provided with stopper plate portion and detent Me part missing in the piston pipe may be constituted by a stop member which is restricted. Since it constitutes a hole and stop member and with the strain and stopper portion and detent Me unit, there is an advantage that necessary to provide separately and stopper portion and detent Me portion omission is eliminated.

Further, stopper plate portion omission has a pin member inserted in the annular groove along the circumferential direction provided on the mounting member with protruding toward the inner peripheral side is attached to the piston pipe, around and stopper portions piston pipe It may be a concave portion provided on one side of the mounting member and a convex portion provided on the other side of the piston pipe and the mounting member. With the shock absorber configured in this way, the assembly work of assembling the piston pipe to the mounting member becomes easy.

Further, the outer diameter of the press-fitting portion of the mounting member may be larger than the outer diameter of the seal holding portion on which the seal ring is mounted. In this case, the piston pipe does not excessively interfere with the seal ring when the piston pipe is press-fitted into the press-fitting portion, and the seal ring can be protected.

According to the shock absorber of the present invention, there is no risk of damaging the seal ring while preventing the piston pipe from coming off and rotating with respect to the outer shell.

It is a vertical sectional view of the shock absorber in one Embodiment of this invention. It is an enlarged vertical sectional view of a part of the shock absorber in one Embodiment of this invention. It is an enlarged vertical sectional view of a part of the shock absorber in the 1st modification of one Embodiment of this invention. It is an enlarged vertical sectional view of a part of the shock absorber in the 2nd modification of one Embodiment of this invention. FIG. 5 is an enlarged exploded perspective view of a part of a shock absorber in a third modification of the embodiment of the present invention.

Hereinafter, the present invention will be described based on the embodiment shown in the figure. The shock absorber D in one embodiment includes a shock absorber body 1 that has a rod 2 and an outer shell 3 into which the rod 2 enters and exits, and is expandable and contractible, a cylindrical air chamber 4 connected to the rod 2, and an outer. An annular mounting member 5 mounted on the outer circumference of the shell 3, a piston pipe 6 fitted on the outer circumference of the mounting member 5, a rolling diaphragm 7 bridged between the air chamber 4 and the piston pipe 6, and the mounting member 5 the seal ring 8 which is to be attached to a periphery of the includes a detachment preventing Me portion to prevent loss with respect to the mounting member 5 of the piston pipe 6, and a detent Me section to prevent rotation with respect to the mounting member 5 of the piston pipe 6 ..

In this shock absorber D, the lower middle end of FIG. 1 of the outer shell 3 is connected to the axle of a vehicle (not shown), and the rod 2 is connected to the vehicle body of a vehicle (not shown) so that the outer shell 3 can be interposed between the vehicle body and the axle. ing. Then, in the shock absorber D, the shock absorber main body 1 exerts a damping force due to the relative movement of the rod 2 and the outer shell 3 in the axial direction, that is, expansion and contraction, and suppresses vehicle body vibration.

Then, gas is filled in the air chamber G partitioned by the air chamber 4, the piston pipe 6, and the rolling diaphragm 7 on the outer periphery of the shock absorber body 1, and the air that urges the shock absorber body 1 in the extension direction by these. A spring S is configured. In the air spring S, the internal pressure fluctuates due to a change in the volume of the air chamber G as the shock absorber body 1 expands and contracts, and at that time, the air spring S exerts an elastic force according to the pressure. When intervened between the air springs S, the air spring S functions as a suspension spring parallel to the shock absorber body 1. The usage pattern of the shock absorber D is not limited to the usage pattern interposed between the vehicle body and the axle.

Hereinafter, each part will be described in detail. The shock absorber body 1 is a double cylinder type in this example, and although not shown, a cylinder housed in the outer shell 3 and a piston movably housed in the cylinder and connected to the rod 2 It is equipped with a chamber filled with two working liquids partitioned by pistons in the cylinder and a reservoir chamber formed between the cylinder and the outer shell 3 so as to exert a damping force when expanding and contracting. It has become. The shock absorber body 1 may be a double-cylinder type or a single-cylinder type. When the shock absorber body 1 is set to a single-cylinder type, a piston is slidably inserted into the outer shell 3 to form an outer. A chamber may be provided in the shell to be filled with two working fluids.

An annular mounting member 5 is provided on the outer periphery of the outer shell 3. As shown in FIG. 2, the mounting member 5 has an annular shape having an upper end portion 5a in order from the upper end and an annular grooves 5c and 5c having an outer diameter larger than that of the upper end portion 5a and accommodating two seal rings 8 and 8. The seal holding portion 5b provided, the press-fitting portion 5d having a larger outer diameter than the seal holding portion 5b and press-fitting the piston pipe 6, and the mounting member 5 of the piston pipe 6 having an outer diameter larger than the press-fitting portion 5d. On the other hand, it is provided with a stopper portion 5e that regulates downward movement. Therefore, the press-fitting portion 5d is provided on the anti-air chamber side of the seal holding portion 5b of the mounting member 5. The area between the seal holding portion 5b and the press-fitting portion 5d on the outer circumference of the mounting member 5 is a tapered surface, and the diameter is gradually increased.

The inner diameter of the mounting member 5 is a diameter that can be fitted to the outer shell 3. Then, after the mounting member 5 is fitted at a predetermined position on the outer circumference of the outer shell 3, the upper end portion 5a is welded with the gap between the upper end surface of the upper end portion 5a and the outer circumference of the outer shell 3 as a groove. It is immovably attached to the outer shell 3 by.

Further, a seal ring 8 made of an O-ring is mounted on each of the annular grooves 5c and 5c of the mounting member 5. The seal ring 8 may be a seal other than the O-ring as long as it is annular.

The piston pipe 6 has a cylindrical shape, the diameter of the upper end side is expanded, and a predetermined space is formed between the piston pipe 6 and the outer shell 3. As shown in FIG. 2, the lower end of the piston pipe 6 has a fitting portion 6a whose diameter has been expanded so that the mounting member 5 can be press-fitted into the press-fitting portion 5d, and a fitting portion 6a above the fitting portion 6a. The air chamber 4 side is provided with a seal facing portion 6b that has a diameter smaller than that of the fitting portion 6a and can be fitted to the seal holding portion 5b. The inner diameter of the fitting portion 6a is larger than the outer diameter of the seal holding portion 5b and smaller than the outer diameter of the press-fitting portion 5d.

Then, in order to mount the piston pipe 6 on the mounting member 5, the outer shell 3 is inserted into the piston pipe 6 from above in FIG. 1 while approaching the mounting member 5, and the lower end of the piston pipe 6 is attached to the stopper portion 5e. Push it in until it touches. Then, the fitting portion 6a is press-fitted into the press-fitting portion 5d of the mounting member 5, and the piston pipe 6 is fixed to the mounting member 5. The press-fitting portion 5d is provided on the anti-air chamber side of the sealing ring 8 of the mounting member 5, and the outer diameter of the press-fitting portion 5d is larger than the outer diameter of the seal holding portion 5b. Therefore, when the fitting portion 6a is press-fitted into the press-fitting portion 5d, the inner diameter of the fitting portion 6a becomes larger than the outer diameter of the seal holding portion 5b. Does not interfere excessively with 8. Therefore, when the piston pipe 6 is attached to the attachment member 5, the piston pipe 6 does not attack the seal ring 8, so that there is no possibility that the seal ring 8 is damaged and gas leaks from the air chamber G. Further, since the press-fitting portion 5d into which the piston pipe 6 is press-fitted is provided on the anti-air chamber side of the sealing ring 8 of the mounting member 5, when the piston pipe 6 is mounted on the mounting member 5, the fitting portion 6a and the fitting portion 6a are provided. Even if wear debris is generated due to rubbing against the press-fitting portion 5d, the seal ring 8 can prevent the wear debris from entering the air chamber G. The inner circumference of the end portion of the fitting portion 6a of the piston pipe 6 is tapered so that the mounting member 5 can be inserted smoothly.

When the piston pipe 6 is mounted on the mounting member 5 in this way, the mounting member 5 is immovably fixed to the outer shell 3 and the piston pipe 6 is press-fitted into the mounting member 5, so that the piston pipe 6 is attached to the outer shell 3. The shell 3 and the mounting member 5 are prevented from coming off and rotating. Therefore, stopper plate portion and detent Me part missing in this embodiment is constituted by a press-fit portion 5d provided in the attachment member 5.

The diameter of the fitting portion 6a at the lower end, which is the tip of the piston pipe 6, does not have to be expanded, and as shown in FIG. 3, the seal holding portion 5b of the mounting member 5 does not have to change the diameter of the piston pipe 6. Since the outer diameter is smaller than the outer diameter of the press-fitting portion 5d, it is possible to prevent the seal ring 8 from being damaged when the piston pipe 6 is press-fitted into the mounting member 5. However, if the diameter of the fitting portion 6a is increased, the clearance between the fitting portion 6a and the seal holding portion 5b can be increased, so that the effect of preventing the seal ring 8 from being scratched can be more reliably achieved.

Returning, the rod 2 is attached with an air chamber 4 which is cylindrical and has an inner diameter larger than the outer diameter of the piston pipe 6. Therefore, when the shock absorber body 1 expands and contracts, the air chamber 4 allows the upper end of the piston pipe 6 to enter and exit.

The rolling diaphragm 7 has a cylindrical shape, and one end 7a, which is the lower end in FIG. 1, is folded inward, and is tightly fixed to the outer periphery of the upper end in FIG. 1 of the piston pipe 6 by a fixing band 9. Is tightly fixed to the outer periphery of the air chamber 4 by a fixing band 10. Further, a cylindrical cover 11 is attached to the lower end of the air chamber 4 from the outer circumference of the rolling diaphragm 7.

In the shock absorber D configured in this way, when the shock absorber main body 1 expands and contracts, the piston pipe 6 moves closer to the air chamber 4. As the shock absorber body 1 expands and contracts, the rolling diaphragm 7 is guided by the cover 11 to change the folding position, allowing the relative movement of the air chamber 4 and the piston pipe 6 to increase the volume in the air chamber G. Change. Therefore, when the shock absorber D expands and contracts, the volume inside the air chamber G changes and the internal pressure changes, and the air spring S repels the shock absorber body 1 in the extension direction according to the pressure of the air chamber G. Demonstrate power.

The shock absorber D of the present invention has a shock absorber body 1 that has a rod 2 and an outer shell 3 into which the rod 2 enters and exits, and is expandable and contractible, a cylindrical air chamber 4 connected to the rod 2, and an outer. An annular mounting member 5 that is immovably mounted on the outer periphery of the shell 3 and a cylindrical tip that is fitted to the outer periphery of the mounting member 5 and the base end side is inside the air chamber 4 due to expansion and contraction of the shock absorber body 1. The piston pipe 6 that goes in and out, the rolling diaphragm 7 that spans the air chamber 4 and the piston pipe 6, the seal ring 8 that is mounted on the outer circumference of the mounting member 5 and adheres to the inner circumference of the piston pipe 6, and the mounting member 5 and a detent Me portion for preventing the rotation of the stopper plate portion dropout preventing detachment of the piston pipe 6 and with respect to the mounting member 5 in the circumferential direction of the piston pipe 6 than the sealing ring 8 in the counterforce air chamber side. In the thus configured damper D, and stopper portions and detent Me portion missing is provided in the counter-air chamber side of the seal ring 8 of the mounting member 5, the mounting member 5 of the piston pipe 6 outer shell It is possible to prevent the piston pipe 6 from attacking the seal ring 8 when the piston pipe 6 is attached to the attachment member 5 while preventing the piston pipe 6 from coming off and rotating. Therefore, according to the shock absorber D of the present invention, there is no risk of damaging the seal ring 8 while preventing the piston pipe 6 from coming off and rotating with respect to the outer shell 3. Further, since the piston pipe 6 is prevented from coming off and rotating with respect to the outer shell 3, twisting of the rolling diaphragm 7 is prevented, and when the shock absorber D expands and contracts, unfavorable resistance is generated due to friction or the like. No problem arises.

Moreover, press-fitting the damper D of the present embodiment, the front end inner periphery of the piston pipe 6 the stopper plate portion and the detent Me portion provided from the sealing ring 8 of the outer periphery of the mounting member 5 in the counter-air chamber side omission is pressed Part 5d. According to the shock absorber D configured in this way, it is possible to prevent the piston pipe 6 from coming off and rotating from the outer shell 3 by press-fitting the piston pipe 6 into the mounting member 5, and to prevent the piston pipe 6 from coming off and rotating. Since it is not necessary to add the parts of the above, the cost is excellent and the assembly work is easy.

Further, the outer diameter of the press-fitting portion 5d in the mounting member 5 may be larger than the outer diameter of the seal holding portion 5b on which the seal ring 8 is mounted. In this case, the piston pipe 6 does not excessively interfere with the seal ring 8 when the piston pipe 6 is press-fitted into the press-fitting portion 5d, and the seal ring 8 can be protected.

Incidentally, stopper plate portion and detent Me portion omission may be configured as follows. As shown in FIG. 4, a hole 6c for communicating inside and outside is provided in the fitting portion 6a provided on the tip side of the piston pipe 6, and as a stopping member mounted on the anti-air chamber side from the seal ring 8 of the mounting member 5. The screw 12 of the above may be inserted into the hole 6c.

Specifically, the screw 12 is screwed into the screw hole 5f provided on the anti-air chamber side from the seal ring 8 of the mounting member 5 and mounted on the mounting member 5. Screw holes 5f are provided in the hole 6c provided in the piston pipe 6 can face position, is adapted to be inserted a screw element 1 2 into the hole 6c. Then, when the screw 12 is inserted into the hole 6c, the piston pipe 6 is restricted from coming out upward with respect to the outer shell 3 and rotating in the circumferential direction. In this example, the stopper plate portion and detent Me part missing, is constituted by the holes 6c and the screw 12, even in this way, can block the loss for the outer shell 3 of the piston pipe 6 rotates and. Since it constitutes a stopper plate portion and detent Me part missing in the hole 6c and the screw element 1 2, there is an advantage that necessary to provide separately and stopper portion and detent Me portion omission is eliminated. In addition to the screw, the stopping member may be a pin that is fixed by press fitting or the like inserted into the hole provided in the mounting member 5, and is one that protrudes from the mounting member 5 and can be inserted into the hole 6c. All you need is. Further, the stopping member may be one in which a hole is provided in the mounting member 5 and fixed to the hole 6c of the piston pipe 6 and inserted into the hole of the mounting member 5. That is, the stop member is inserted into the hole 6c and is provided on the anti-air chamber side of the seal ring 8 of the mounting member 5, and its movement is restricted in the axial direction and the circumferential direction of the mounting member 5. All you need is.

Further, stopper plate portion and detent Me portion omission may be configured as follows. As shown in FIG. 5, omission and stopper portion, the anti-air chamber side of the seal ring 8 of the mounting member 5 with protruding toward the inner peripheral side is attached to the fitting portion 6a provided on the tip side of the piston pipe 6 It is configured to have a pin member 13 inserted into an annular groove 5g along the provided circumferential direction. Also, detent Me unit, as shown in FIG. 5, and the convex portion 5h provided on the stopper portion 5e of the seal ring 8 of the piston pipe 6 and the mounting member 5 is provided in the counter-air chamber side, the tip of the piston pipe 6 It is composed of a recess 6d provided in the above.

When the piston pipe 6 is fitted to the outer periphery of the mounting member 5 while the convex portion 5h is inserted into the concave portion 6d, the rotation of the piston pipe 6 is restricted with respect to the mounting member 5, so that the outer shell 3 is restricted from rotating. Is also stopped in the circumferential direction. The convex portion 5h and the concave portion 6d are each formed in the axial direction so that they can be visually recognized from the outside. The convex portion may be provided on the piston pipe 6 and the concave portion may be provided on the mounting member 5.

The pin member 13 is a push clip attached to a hole 6e provided so as to communicate the inside and outside of the fitting portion 6a of the piston pipe 6, and when inserted into the hole 6e, the tip protrudes into the piston pipe 6. It is fixed to the piston pipe 6 in this state. The pin member 13 may be a screw, as long as it can be fixed in a state of protruding inward of the piston pipe 6. When the piston pipe 6 is fitted to the mounting member 5, the hole 6e faces the annular groove 5g provided on the outer periphery of the mounting member 5, and when the pin member 13 is mounted in the hole 6e, the tip thereof is inserted into the annular groove 5g. .. In this way, the attachment member 5 of the piston pipe 6 is prevented from coming off in the axial direction, so that the outer shell 3 is also prevented from coming off.

Even in this way, it is possible to prevent the piston pipe 6 from coming off and rotating with respect to the outer shell 3. Then, a pin member 13 which is inserted into an annular groove 5g along the stopper plate portion missing is provided in the mounting member 5 with protruding toward the inner peripheral side is attached to the distal end side of the piston pipe 6 circumferential direction It is configured. Therefore, even if the piston pipe 6 is not aligned with the mounting member 5 in the circumferential direction, the pin member 13 can be prevented from coming off simply by inserting the pin member 13 into the annular groove 5g, which facilitates assembly. Further, when rotation stopper plate portion of the fitting of the piston pipe 6 and the mounting member 5 when the one in provided recesses and piston pipe 6 and the convex portion provided in the other mounting member 5 of the piston pipe 6 and the mounting member 5 The concave and convex parts can be visually recognized, and assembly is easy. From the above, in the shock absorber D of this example, the assembly work of assembling the piston pipe 6 to the mounting member 5 becomes easy.

Although the preferred embodiments of the present invention have been described in detail above, they can be modified, modified, and modified as long as they do not deviate from the claims.

1 ... shock absorber body, 2 ... rod, 3 ... outer shell, 4: air chamber, 5 ... mounting member, 5d ... press-in portion (retaining stopper plate portion and detent Me Part ), 5g ... annular groove, 5h ... convex part, 6 ... piston pipe, 6c ... hole, 7 ... rolling diaphragm, 8 ... seal ring, 12 ... screw ( Stop member), 13 ... Pin member

Claims (1)

A shock absorber body that has a rod and an outer shell into which the rod enters and exits and can be expanded and contracted.
A cylindrical air chamber connected to the rod and
An annular mounting member that is immovably mounted on the outer circumference of the outer shell,
A piston pipe that is cylindrical and whose tip is fitted to the outer circumference of the mounting member and whose base end side moves in and out of the air chamber due to expansion and contraction of the shock absorber body.
A rolling diaphragm bridged between the air chamber and the piston pipe,
A seal ring mounted on the outer circumference of the mounting member and in close contact with the inner circumference of the piston pipe.
Missing the stopper plate portion dropout preventing the piston pipe with respect to the mounting member than in the counterforce air chamber side said sealing ring of said mounting member,
E Bei and said detent Me section to prevent rotation of the at counter-air chamber side of the seal ring in the circumferential direction of the piston pipe to the mounting member of the mounting member,
The mounting member has a press-fitting portion which is an outer periphery and is provided on the anti-air chamber side of the seal ring and the inner circumference of the tip of the piston pipe is press-fitted.
The outer diameter of the press-fitting portion of the mounting member is larger than the outer diameter of the seal holding portion on which the seal ring is mounted.
A shock absorber characterized in that the press-fitting portion is the retaining portion and the detent portion.

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