JP5651330B2 - Bump cushion - Google Patents

Description

  The present invention relates to a bump cushion that restricts contraction of a damper with an air spring.

  In general, in a damper interposed between a vehicle body and an axle in a vehicle, a bump cushion is attached to the rod end in order to limit the contraction of the damper itself and reduce the impact at the time of the most contraction. Specifically, the bump cushion is configured to abut against a bump stopper fixed to the cylinder end of the damper, thereby limiting the contraction of the damper itself and mitigating the impact.

  On the other hand, in recent years, air suspensions using suspension springs as air springs have been put to practical use for the purpose of further improving ride comfort and adjusting the vehicle height. In such air suspensions, an air chamber is provided around the rod. A damper with an air spring in which a damper and an air spring are integrated has been widely adopted.

  In such a damper with an air spring, since the air chamber is provided around the rod, a bump cushion fixed to the end of the rod is also disposed in the air chamber (see, for example, Patent Document 1).

JP-A-11-37200

  By the way, the bump cushion accommodated in an air chamber is provided with the cup fixed to a rod end, and the cylindrical cushion rubber fixed by press-fitting in a cup. More specifically, the cup includes an annular bottom portion and an outer cylinder that rises from the outer periphery of the bottom portion. The cup and the cushion rubber are integrated by press-fitting the outer periphery of the base end portion of the cushion rubber into the outer cylinder. Is planned.

  By pressing the cushion rubber into the outer cylinder in this way, the cushion rubber is reduced in diameter by the gas pressure in the air chamber, preventing the cushion rubber from falling off the cup, and the cushion rubber collides with the bump stopper. When compressed, it is prevented from interfering with an air piston or an air chamber that expands in diameter and forms an air chamber.

  However, even with the above-mentioned considerations, if the pressure in the air chamber becomes high, the cushion rubber will be greatly deformed and there is a concern that it will fall out of the cup. If the allowance is increased, a new problem arises that it becomes difficult to press-fit the cushion rubber into the cup.

  Therefore, the present invention was devised to improve the above-described problems, and the object of the present invention is to reliably prevent the cushion rubber cup from falling off and to easily attach the cushion rubber to the cup. It is to provide a bump cushion that can.

To achieve the above object, problem solving hand stage of the present invention, between the sheet Linda, a rod is inserted in the cylinder, an air chamber formed around said rod, said cylinder and said rod in the bump cushion limit is attached to the rod end of the air spring with a damper having an air spring, the shrinkage of the fixed bump stopper and abutted to the air sprung damper to the cylinder end interposed, a cup fixed to the rod end, and a cylindrical cushion rubber is inserted into the cup, the cup, the cup body having an outer cylinder raised from the outer periphery of the bottom portion and the annular bottom part, wherein and a Uchitsutsu member having a inner cylinder while being press-fitted into the outer tube of the cup body, a proximal end portion of the cushion rubber is inserted into the outer tube, the click The inner cylinder is fitted into the proximal end inner peripheral of Deployment rubber, characterized by comprising.

According to the bump cushion of the present invention, it is possible to prevent the cushion rubber from falling off the cup regardless of the pressure in the air chamber, and the press-fitting allowance of the cushion rubber is set excessively. Since there is no need to press-fit the cushion rubber into the cup, the cushion rubber can be easily assembled to the cup. Further, since the cup is composed of the cup body and the inner cylinder member, when the pressure in the air chamber is relatively low, the cushion rubber is fitted to the inner cylinder member to prevent the cup from falling off. Even if the gas pressure in the air chamber becomes high, the cushion rubber is reduced in diameter and the base end portion cannot be maintained in the outer cylinder, the inner periphery of the base end portion is reduced. Since the tightening force for tightening the inner cylinder of the inner cylinder member in the cup increases, the cushion rubber does not fall off from the cup. Therefore, it is not necessary to set the cushion rubber press-fitting allowance excessively and press-fit the cushion rubber into the cup, so that the cushion rubber can be easily assembled to the cup.

It is a longitudinal cross-sectional view of the damper with an air spring to which the bump cushion in one embodiment of this invention was applied. It is an expanded sectional view of the bump cushion in one embodiment of the present invention. It is an expanded sectional view of the bump cushion in one modification of one embodiment of the present invention. It is an expanded sectional view of the bump cushion in other embodiments of the present invention. It is an expanded sectional view of the bump cushion in one modification of other embodiments of the present invention.

  Hereinafter, the present invention will be described based on an embodiment shown in the drawings. As shown in FIG. 1, the bump cushion 1 in one embodiment is attached to a rod 6 in a damper D with an air spring. In the contraction stroke of the damper D with an air spring, the cylinder 5 of the damper D with an air spring Abutting against the bump stopper 7 provided at the end, the contraction of the damper D with the air spring is restricted and the impact at the time of the most contraction is reduced.

  On the other hand, a damper D with an air spring to which the bump cushion 1 is applied includes a damper body 4 having a cylinder 5 and a rod 6 inserted into the cylinder 5 and an air spring S, as shown in FIG. It is prepared for. The air spring S has an air piston 8 fixed to the cylinder 5 in the damper main body 4, an air chamber 9 fixed to the rod 6 in the damper main body 4, and has a cylindrical shape and one end fixed to the air piston 8. And a diaphragm 10 whose other end is fixed to the air chamber 9, and these form an air chamber G around the rod.

  The air spring S functions as an air spring that urges the damper main body 4 in the extending direction by the pressure of the gas sealed in the air chamber G, and responds to the volume change of the air chamber G accompanying the expansion and contraction of the damper main body 4. It is designed to demonstrate its elasticity. Therefore, for example, when the damper 1 with an air spring is interposed between the vehicle body and the axle, the air spring S in the damper D with the air spring functions as a suspension spring that is juxtaposed with the damper main body D. .

  The damper D with an air spring configured as described above is used, for example, interposed between the vehicle body and the axle as described above, and exhibits a damping force in the damper main body 4 when expanding and contracting. The spring S exerts an elastic force to suppress the vibration of the vehicle body.

  The bump cushion 1 includes a cup 2 that is fixed to the rod 6 via a mount M, and a cylindrical cushion rubber 3 that is inserted into the cup 2. Is housed in.

  As shown in FIG. 2, the cup 2 includes an annular bottom 2a that allows the rod 6 to pass therethrough, an outer cylinder 2b into which the base end 3a of the cushion rubber 3 rises from the outer periphery of the bottom 2a, and the bottom 2a. An inner cylinder 2c that rises from the inner periphery and fits to the inner periphery of the base end portion 3a of the cushion rubber 3 is configured. The outer periphery of the tip of the inner cylinder 2c is provided with a curved surface 2d.

  The mount M includes a lower mount member 11 fixed to the tip of the rod 6, a cylindrical mount case 14 that holds the outer periphery of the lower mount member 11 and includes an air chamber 8 on the outer periphery, and an anti-vibration rubber 13. And an upper mount member 12 that rotatably holds the air chamber 8.

  The cup 2 is integrated with the mount case 14 by fixing the bottom 2a to the mount case 14 by welding or the like. In this way, the cup 2 is fixed to the upper end in FIG. It is fixed to the rod 6 through the mount M to be mounted.

  The lower mount member 11 of the mount M is formed by integrating a pair of cylinders having different diameters with anti-vibration rubber that is fused, welded, or bonded thereto, and the cup 2 is directly welded to the lower mount member 11. Therefore, a mount case 14 for fixing the cup 2 to the mount M is provided. The lower mount member 11 is mounted on the outer periphery of a small diameter portion 6 a provided at the tip of the rod 6, and a collar 15 is interposed between the lower mount member 11 and a step portion formed at the boundary of the small diameter portion 6 a of the rod 6. . The collar 15 is laminated on the step portion as described above when the difference between the small diameter portion 6a of the rod 6 and the outer diameter of the other portion is small and a sufficient contact area between the mount M and the lower mount member 11 cannot be secured. This is provided in order to sufficiently secure the contact area, and is fixed to the rod 6 in advance so that excessive contact surface pressure does not act on the mount M.

  Therefore, the inner diameter of the bottom 2a of the cup 2 and the inner diameter of the cushion rubber 3 are set to be larger than the outer diameter of the collar 15, so that the assembly of the cup 2 and the cushion rubber 3 is not hindered. If the contact area can be secured without using the collar 15, the collar 15 may be omitted.

  As shown in FIG. 2, the cushion rubber 3 is cylindrical and has a base end portion 3 a having a large outer diameter, an intermediate portion 3 b having an outer diameter smaller than the base end portion 3 a, and an intermediate portion 3. A distal end portion 3c having a small outer diameter, an annular recess portion 3d provided between the base end portion 3a and the intermediate portion 3b, and an annular recess portion 3e provided between the intermediate portion 3b and the distal end portion 3c. Configured.

  Then, the cushion rubber 3 is inserted by inserting the base end 3a of the cushion rubber 3 into the outer cylinder 2b of the cup 2 and fitting the inner periphery of the base end 3a to the outer periphery of the inner cylinder 2c of the cup 2. Fix to cup 2.

  Returning, an enlarged diameter portion 3 f is provided on the inner circumference of the base end portion 3 a, and the enlarged diameter portion 3 f can be fitted to the outer circumference of the inner cylinder 2 c of the cup 2. In addition, since the tip outer periphery of the inner cylinder 2c of the cup 2 is provided with the curved surface 2d, the expanded diameter portion 3f is damaged to the inner periphery of the inner cylinder 2c when the cushion rubber 3 is fitted into the cup 2. It can guide smoothly without. By providing the enlarged diameter portion 3f in this way, the inner circumference other than the enlarged diameter portion 3f of the cushion rubber 3 is opposed to the vicinity of the outer circumference of the rod 6 to increase the outer diameter while securing the volume of the cushion rubber 3. It can be avoided. Further, the inner diameter of the cushion rubber 3 can be brought into contact with the outer circumference of the rod 6 by the reduced diameter of the inner circumference of the cushion rubber 3 when the cushion rubber 3 collides with the bump cushion 7 and is compressed. There is also an advantage that bending can be prevented.

  The bump stopper 7 has an annular shape and is fixed to the upper end of the cylinder 5 in FIG. 1 so as to face the front end portion 3 c of the cushion rubber 3. When the damper D with the air spring contracts and strokes a predetermined amount, the cushion rubber 3 abuts against the bump stopper 7 and reduces the impact while pressing and shrinking and restricts the contraction of the damper D with the air spring.

  The bump cushion 1 configured in this way is housed in the air chamber G as described above, and is constantly receiving the pressure of the gas in the air chamber G. When the pressure is relatively low, the cushion rubber 3 is prevented from falling off the cup 2 because the base end 3a is fitted to the inner cylinder 2c of the cup 2. On the other hand, even if the gas pressure in the air chamber G becomes high and the cushion rubber 3 is deformed in a reduced diameter, the tightening force that the inner periphery of the base end 3a tightens the inner cylinder 2c of the cup 2 increases. The cushion rubber 3 does not fall off from 2.

  In this way, the cushion rubber 3 can be prevented from falling off, so there is no need to press the cushion rubber 3 into the cup 2 by setting the press-fitting allowance of the cushion rubber 3 to be excessive.

  As described above, in the bump cushion 1 of the present embodiment, the cushion rubber 3 can be prevented from falling off the cup 2 regardless of the pressure in the air chamber G. In addition, since it is not necessary to press-fit the cushion rubber 3 into the cup 2 by setting the press-fitting allowance of the cushion rubber 3 excessively, the cushion rubber 3 can be easily assembled to the cup 2.

  Further, in the case of this embodiment, since the curved surface 2d is provided on the outer periphery of the tip of the inner cylinder 2c of the cup 2, when the cushion rubber 3 is fitted into the cup 2, the enlarged-diameter portion 3f is provided in the inner cylinder. It is possible to guide smoothly without damaging the inner periphery of 2c, and the assembling property can be further improved.

  The outer diameter of the base end 3a of the cushion rubber 3 is set larger than the inner diameter of the outer cylinder 2b of the cup 2, and the base end 3a of the cushion rubber 3 is lightly press-fitted into the outer cylinder 2b of the cup 2. Accordingly, the cushion rubber 3 may be held by the outer cylinder 2b.

  As described above, when the base end 3a of the cushion rubber 3 is lightly press-fitted into the outer cylinder 2b of the cup 2 with a press-fitting allowance, the base end 3a is loosely fitted to the inner cylinder 2c under atmospheric pressure. If the cushion rubber 3 is deformed by the pressure in the air chamber G and the base end portion 3a cannot be maintained in the outer cylinder 2b, the base end portion 3a can be maintained. However, the inner cylinder 2c may be tightened so that the cushion rubber 3 can be prevented from falling off the cup 2.

  In addition, when the base end portion 3a of the cushion rubber 3 is fitted or lightly press-fitted into the outer cylinder 2b of the cup 2, the tip of the outer cylinder 2b is bent toward the outer peripheral side to be expanded, whereby the cushion rubber 3 The base end portion 3a can be smoothly guided into the cup 2 without being damaged. Further, when the outer cylinder 2b holds the outer periphery of the base end portion 3a of the cushion rubber 3, a reduced diameter portion is provided in the middle of the outer cylinder 2b, and the base end portion 3a of the cushion rubber 3 is further tightened by the outer cylinder 2b. The cushion rubber 3 may be held firmly by the outer cylinder 2b, and a method other than light press-fitting may be employed. For example, the base end 3a of the cushion rubber 3 is held. It may be held in such a manner.

  As shown in FIG. 3, if the diameter of the tip end side of the inner cylinder 2c is increased, the cushion rubber 3 can be further prevented from coming off. Since the diameter of the inner cylinder 2c only needs to be increased, as shown in the drawing, it is possible to adopt a shape in which only the diameter of the front end side is increased in addition to the diameter increasing toward the front end side. is there.

  Moreover, the cup 17 can also be comprised with the cup main body 18 and the inner cylinder member 19 like the bump cushion of other embodiment shown in FIG. The bump cushion 16 is different only in the configuration of the bump cushion 1 and the cup 17 of the above-described embodiment, and the other configuration is the same as described above. Detailed description of the portion will be omitted.

  The cup 17 includes the cup body 18 and the inner cylinder member 19 as described above. The cup body 18 includes an annular bottom portion 18a that allows the rod 6 to be inserted, and an outer cylinder 18b that rises from the outer periphery of the bottom portion 18a. On the other hand, the inner cylinder member 19 is configured to include an annular seat 19a on which the upper end of the cushion rubber 3 in FIG. 3 is seated, and an inner cylinder 19b that rises from the inner periphery of the seat 19a. The outer periphery of 19a is press-fitted into the inner periphery of the outer cylinder 18b of the cup body 18, and both are integrated.

  The cup body 18 and the inner cylinder member 19 may be made of a material that is small in deformation even when subjected to the pressure in the air chamber G, but the cup body 18 is assumed to be welded to the mount case 14. If it is, it will be set as a metal and the inner cylinder member 19 can use hard resin etc. besides a metal.

  Then, the expanded diameter portion 3 f of the cushion rubber 3 is fitted into the inner cylinder 19 b of the inner cylinder member 19, and the cushion rubber 3 is fixed to the cup 17.

  Even when the cup 17 is configured by the cup body 18 and the inner cylinder member 19 as described above, the cushion rubber 3 is fitted to the inner cylinder member 19 when the pressure in the air chamber G is relatively low. Accordingly, the cup 17 is prevented from falling off, the gas pressure in the air chamber G becomes high, the cushion rubber 3 is reduced in diameter, and the base end portion 3a cannot be maintained in the outer cylinder 18b. Even if such a situation occurs, the inner periphery of the base end portion 3a increases the tightening force for tightening the inner cylinder 19b of the inner cylinder member 19 in the cup 17, so that the cushion rubber 3 does not fall off from the cup 17.

  In this manner, the cushion rubber 3 can be prevented from falling off the cup 17 without press-fitting the cushion rubber 3 into the inner periphery of the outer cylinder 18b of the cup body 18.

  Therefore, according to the bump cushion 16 of the present embodiment, the cushion rubber 3 can be prevented from falling off the cup 17 regardless of the pressure in the air chamber G, and the cushion rubber. Therefore, it is not necessary to press-fit the cushion rubber 3 into the cup 17 by setting the press-fitting allowance of No. 3 excessively, so that the cushion rubber 3 can be easily assembled to the cup 17.

  As shown in FIG. 5, if the diameter of the tip end of the inner cylinder 19b in the inner cylinder member 19 is increased, the cushion rubber 3 can be further prevented from coming off. Since the diameter of the inner cylinder 19b only needs to be increased, as shown in the drawing, it is possible to adopt a shape in which only the diameter of the front end side is increased in addition to the diameter increasing toward the front end side. is there.

  In this embodiment, the base end 3a of the cushion rubber 3 is held by the outer cylinder 18b by lightly press-fitting the outer periphery of the base end 3a of the cushion rubber 3 into the inner periphery of the outer cylinder 18b. You may do it.

  This is the end of the description of the embodiment of the present invention, but the scope of the present invention is of course not limited to the details shown or described.

  The present invention can be used for a bump cushion of a damper with an air spring that suppresses vibration of a vibration control target such as a vehicle.

DESCRIPTION OF SYMBOLS 1,16 Bump cushion 2,17 Cup 2a Bottom part 2b in cup Outer cylinder 2c in cup Inner cylinder 2d in cup Curl surface 3 in cup Cushion rubber 3a Base end part 3b in cushion rubber Intermediate part 3c in cushion rubber Tip part in cushion rubber 3d, 3e Annular recess 3f in the cushion rubber 3f Expanded part 4 in the cushion rubber 4 Damper body 5 Cylinder 6 Rod 6a Small diameter part 7 in the rod Bump stopper 8 Air piston 9 Air chamber 10 Diaphragm 11 Lower mount member 12 Upper mount member 13 Anti-vibration rubber 14 Mount case 15 Collar 18 Cup body 18a Bottom 18b in cup body Inner cylinder 19 in cup body Inner cylinder member 19a Seat 19b in inner cylinder member In inner cylinder member Inner cylinder D damper with air spring G air chamber M mount S air spring

Claims (5)

Cylinder and a rod that is inserted in the cylinder, an air chamber formed around said rod, said at the air spring with damper and an air spring interposed between said cylinder and said rod rod It is mounted on an end, in a bump cushion to limit the contraction of said cylinder fixed bump stopper end and abuts to the air spring with damper, the cup is secured to the rod end, the tube that is inserted into the cup a Jo cushion rubber, with the cup, and the cup body having an outer cylinder raised from the outer periphery of the bottom portion and the annular bottom part, the inner cylinder while being press-fitted into the outer tube of the cup body and a another within the cylinder member, the cushion base end portion of the rubber is inserted into the outer tube, formed by the inner tube is fitted in a circumferential proximal end portion of the cushion rubber Bump cushion characterized the door. 2. The bump cushion according to claim 1 , wherein the diameter of the inner cylinder increases toward the distal end. 2. The bump cushion according to claim 1 , wherein only the distal end side of the inner cylinder is enlarged in diameter. Bump cushion according to any one of claims 1 to 3, characterized in that for holding the base end outer periphery of the cushion rubber in the outer cylinder in the cup. Bump cushion claimed in any one of 4, characterized in that a reduced diameter portion at a site of the outer cylinder facing the outer periphery of the base portion of the cushion rubber.

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