JP2002206583A - Structure for preventing fall-off of suspension spring in hydraulic shock absorber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a suspension spring from falling off from a surrounding of a piston rod in an hydraulic shock absorber, even if the suspension spring is broken. SOLUTION: In this structure for preventing fall-off of the suspension spring 24 in the hydraulic shock absorber 10, a spring sheet 22 is provided with a spring sheet rubber holding means (holding hole 22A, holding surface 22B), and a spring sheet rubber 32 is provided with a spring holding portion 37.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for preventing a suspension spring of a hydraulic shock absorber from falling off.

[0002]

2. Description of the Related Art Conventionally, in a hydraulic shock absorber, a conventional hydraulic shock absorber has been proposed.
As described in Japanese Patent Application Publication No. H10-260, having a tamper tube and a piston rod, providing a spring seat on the piston rod,
A suspension spring is supported on the spring seat via a spring seat rubber.

[0003]

However, in the prior art, when the suspension spring breaks, the suspension spring clings to the piston rod from its upper and lower ends or cut ends, and then the suspension spring rotates with respect to the piston rod. There is a risk of slipping out of the vicinity of the piston rod due to sliding movement. The dropped suspension spring may come into contact with the tire.

[0004] It is an object of the present invention to prevent a hydraulic shock absorber from coming off around a piston rod and dropping off even if a suspension spring is broken.

[0005]

According to the first aspect of the present invention, there is provided a structure for preventing a suspension spring from falling out of a hydraulic shock absorber in which a suspension spring is supported via a spring seat rubber on an upper spring seat that supports the suspension spring of the hydraulic shock absorber. A spring seat rubber holding means is provided on the spring seat, and a spring holding means is provided on the spring seat rubber.

According to a second aspect of the present invention, in the first aspect of the present invention, the spring holding means is provided at a plurality of positions along a circumferential direction of a spring seating portion provided on a spring seat rubber.

According to a third aspect of the present invention, in the first or second aspect, the spring holding means further includes an inner holding portion for holding the strand of the suspension spring from the inside, and an outer holding portion for holding the wire of the suspension spring from the outside. In addition, a reinforcing portion is attached to the back surface of the inner holding portion.

According to a fourth aspect of the present invention, in the third aspect of the present invention, a lightening portion is further provided in the reinforcing portion.

According to a fifth aspect of the present invention, in the third aspect of the present invention, the outer surface of the outer holding portion is provided to have a smaller diameter than the outer diameter of the spring seat rubber which is fitted and held in the spring seat. A gap is formed between the spring seat and the outer surface of the outer holding portion.

The invention according to claim 6 is the invention according to any one of claims 1 to 5, wherein a dust cover is further integrated with the spring seat rubber via a connecting portion.

[0011]

According to the first aspect of the present invention, the following operations are provided. Even if the suspension spring is broken, the suspension spring is held by the spring seat rubber and does not fall off. Even if the suspension spring falls from the spring seat together with the spring seat rubber, the spring seat rubber holding the suspension spring forms a closed ring around the piston rod, so that they come off from the piston rod and fall off. Never do. Also, even if the suspension spring falls around the piston rod together with the spring seat rubber and the spring seat, the spring seat rubber and the spring seat holding the suspension spring both form a closed loop around the piston rod. Does not come off around the piston rod and fall off.

According to the second aspect of the present invention, the following operations are provided. Since the spring holding means are dispersedly arranged at a plurality of positions in the circumferential direction of the spring seat rubber, the weight of the spring seat rubber can be reduced as compared with a structure in which the spring holding means is continuously arranged on the entire circumference in the circumferential direction.

According to the third aspect of the invention, the following operation is provided. Since the spring holding means has the inner holding portion and the outer holding portion, the suspension spring is firmly held so as to be gripped from inside and outside, and since the back surface of the inner holding portion is reinforced by the reinforcing portion,
The holding strength of the suspension spring can be enhanced.

According to the fourth aspect of the invention, the following operations are provided. Since the lightening portion is provided in the reinforcing portion of the inner holding portion, the spring seat rubber can be reduced in weight while having the above-described reinforcing effect.

According to the fifth aspect of the present invention, the following operations are provided. Since the outer surface of the outer holding portion is provided with a diameter smaller than the outer diameter of the spring seat rubber that is fitted and held in the spring seat, a gap is formed between the spring seat and the outer surface of the outer holding portion. Even when the outer holding portion holds the end portion of the suspension spring without a gap under a state where the suspension spring is assembled into the seat rubber, the end portion corresponds to the above-described reduced-diameter portion of the outer holding portion. As long as the suspension spring is positioned, the displacement of the end of the suspension spring in the radially expanding direction due to the compression deformation can be reliably allowed within the range of the gap.

According to the sixth aspect of the present invention, the following operations are provided. Since the dust cover is integrated with the spring seat rubber, the number of parts can be reduced, the number of steps for attaching the dust cover around the piston rod can be reduced, and the productivity of the hydraulic shock absorber can be improved.

[0017]

FIG. 1 is a sectional view showing a main part of a hydraulic shock absorber, FIG. 2 is a sectional view showing a spring seat rubber of a first embodiment, FIG. 3 is a view showing a spring seat rubber,
(A) is a bottom view cut out and showing an outer peripheral side portion of a spring seat rubber, (B) is a cross-sectional view taken along line BB of (A), and (C) is a view taken along arrow C of (A). FIG. 4 is a sectional view showing a spring seat rubber according to the second embodiment.

(First Embodiment) (FIGS. 1 to 3) A hydraulic shock absorber 10 is a strut damper type, and as shown in FIG. 1, a cylinder (not shown) built in an outer tube 11 (damper tube). ), The piston rod 12 is inserted into the outer tube 11, and the wheel-side mounting bracket 1 is inserted into the outer tube 11.
3 and attached to the vehicle body with a piston rod 12 protruding from the outer tube 11 provided with a vehicle body side mounting bracket 14. The vehicle-body-side mounting bracket 14 includes a collar 15, a mount rubber assembly 18 including upper and lower mount bases 16 </ b> A and 16 </ b> B, and a mount rubber 17. And is fastened with a nut 19.

The hydraulic shock absorber 10 is provided with a tie rod mounting arm 20 to the outer tube 11 and a tie rod is connected thereto, so that a steering force by a steering device (not shown) is transmitted from the outer tube 11 to the wheels to enable steering.

The hydraulic shock absorber 10 includes a lower spring seat 21 fixed to the outer periphery of the outer tube 11 and a vehicle body side mounting bracket 1 installed around the piston rod 12.
A suspension spring 24 is interposed between the upper spring seat 22 and the upper spring seat 22, which is fixed to the thrust bearing 23, which is fixed to the rear surface 4 by light press-fitting and is supported on the rear side. Specifically, the suspension spring 24 is supported by the lower spring seat 21 and is supported by the upper spring seat 22 via the spring seat rubber 30.

The hydraulic shock absorber 10 is provided with a bump rubber 25 which is firmly hung below the mounting bracket 14 of the piston rod 12 on the vehicle body side. Hydraulic shock absorber 10
During the maximum compression, the bump rubber 25 abuts against the bump stopper cap 26 on the upper end surface of the outer tube 11 to regulate the maximum compression stroke.

That is, the hydraulic shock absorber 10 expands and contracts so as to absorb the impact force that the vehicle receives from the road surface by the elastic force of the suspension spring 24. When the piston (not shown) moves up and down due to its expansion and contraction, the hydraulic shock absorber 10 generates its expansion and contraction vibration by damping force generated by a piston valve device provided on the piston, a base valve device provided on the cylinder, and the like. Is quickly suppressed.

However, the hydraulic shock absorber 10 includes the suspension spring 2
The spring seat rubber 30 for supporting the spring 4 on the upper spring seat 22 is configured as shown in FIGS.

The spring seat rubber 30 is formed integrally with a bellows-shaped dust cover 33 via an annular connecting portion 32 provided on the inner periphery of the annular body 31. The lower end of the dust cover 33 can contact a dust cover receiver 26 </ b> A provided on the bump stopper cap 26.

The spring seat rubber 30 is an annular body 3
At each of a plurality of circumferential positions (four positions in the present embodiment) of the upper surface of the upper surface 1, the spring seat 22 is elastically deformed into a holding hole 22 </ b> A provided at a plurality of circumferential positions (four positions in the present embodiment) by press-fitting and engaging. In addition to a locking projection 34 to be stopped, a fitting outer diameter portion 35 that is press-fitted into a holding surface 22 </ b> B provided inside the outer peripheral wall of the spring seat 22 and fitted and held on the outer periphery of the annular body 31. Prepare. Thus, the spring seat rubber 30 is fixedly held by the spring seat 22. The holding hole 22A and the holding surface 22B of the spring seat 22 constitute spring seat rubber holding means.

The spring seat rubber 30 is an annular body 3
1 is provided with a spring seating portion 36 having a concave cross-section that is continuous in the circumferential direction on the lower surface of the lower surface 1.
The element wire on the upper end side of 4 is seated and supported. The spring seat rubber 30 is provided at a plurality of positions (four positions in the present embodiment) along the circumferential direction of the spring seating portion 36 with spring holding portions 37 over a certain length range along the circumferential direction. The spring holding portion 37 has an inner holding portion 38 for holding the wire on the upper end side of the suspension spring 24 from the inside and an outer holding portion 39 for holding the wire from the outside. The inner holding portion 38 and the outer holding portion 39 forms a wire gripping surface 40 for gripping and holding a range exceeding 180 degrees of the outer periphery of the cross section of the wire of the suspension spring 24 (FIG. 2).

The spring seat rubber 30 is provided with the outer surface 39A of the outer holding portion 39 reduced in diameter with respect to the fitting outer diameter portion 35 fitted and held on the holding surface 22B of the spring seat 22 described above. A gap A (see FIG. 3) between the holding surface 22B of the holding member 22 and the outer surface 39A of the outer diameter holding portion 39.
(A)) is formed. In addition, the spring seat rubber 30
Is provided with a protruding restraining portion 41 that is in contact with the holding surface 22B of the spring seat 22 without a gap outside the outer shape holding portion 39, and restrains the radial position of the suspension spring 24 held by the outer holding portion 39. In addition, the spring seat rubber 30 is configured such that a wire at the upper end portion side of the suspension spring 24 is disposed at a central portion between the adjacent spring holding portions 37 along the circumferential direction of the spring seat portion 36 from the outer peripheral side thereof. The suspension spring 24 is restrained.
Is provided with a projecting centering portion 42 for centering the entirety with respect to the spring seat rubber 30. The outer peripheral surface of the element wire of the suspension spring 24 centered by the centering portion 42 has a clearance between the spring seating portion 36 along the circumferential direction of the spring seating portion 36 except for the outer holding portion 39 and the centering portion 42. B is given.

The spring seat rubber 30 is configured such that the above-described reduced diameter outer surface 39A of the outer holding portion 39 is
The upper end (element wire) of the suspension spring 24 is located at a position corresponding to the range where the above-mentioned gap A is formed between the second holding surface 22B and the range where the spring seating part 36 forms the above-mentioned gap B. When the suspension end is positioned, displacement of the upper end of the suspension spring 24 in the radially expanding direction due to compression deformation can be allowed within the range of the gaps A and B. The suspension spring 24
Is designed so that the mounting position on the spring seat 22 is determined at the mounting stage. For this reason, the spring seat rubber 30 connects the suspension spring 24 to the spring seat 3
6 so that the position of the upper end of the strand of the suspension spring 24 is set to a proper assembling position corresponding to the range in which the gaps A and B are formed when the suspension spring 24 is assembled so as to be seated thereon. A part of the outer peripheral surface of the 31 (in this embodiment, the outer surface of the protruding restraining portion 41 provided outside the outer holding portion 39) is provided with a positioning protrusion 43 for alignment with the spring seat 22 (holding surface 22B). By engaging the positioning projection 43 of the spring seat rubber 30 with a positioning recess (not shown) provided on the holding surface 22B of the spring seat 22, the suspension spring 24 attached to the proper mounting position on the spring seat 22 is formed. Can be positioned at the above-described proper assembling position with respect to the spring seat rubber 30.

The spring seat rubber 30 is provided on the back of the inner holding portion 38 of the spring holding portion 37 with the reinforcing portion 4.
5 is attached. The reinforcing portion 45 is connected from the lower end of the back surface of the inner holding portion 38 to the connecting portion 3 with the dust cover 33.
2, a plate-like horizontal portion 45A extending horizontally and an inner holding portion 38
And a plate-like substantially triangular portion 45B extending perpendicularly to the connecting portion 32 from both side ends of the rear surface of the inner holding portion 38. A concave hollow portion 46 is formed by the rear surface of the inner holding portion 38, the horizontal portion 45A and the triangular portion 45B.

Therefore, in the hydraulic shock absorber 10, the vehicle body side mounting bracket 14 provided on the piston rod 12 is provided.
A thrust bearing 23 is fixed to the thrust bearing 23 by light press fitting or the like, and a spring seat 22 is fixed to the thrust bearing 23 by light press fitting or the like.
2A, the spring seat rubber 30 is fixedly held by the holding surface 22B, and the spring holding portion 37 of the spring seat rubber 30 (the inner holding portion 38, the outer holding portion 3).
9) The wire at the upper end of the suspension spring 24 is restrained and used.

The hydraulic shock absorber 10 has the following operations. Even if the suspension spring 24 breaks, the suspension spring 24 is held by the spring seat rubber 30 and does not fall off. still,
Even if the suspension spring 24 drops from the spring seat 22 together with the spring seat rubber 30, the spring seat rubber 30 holding the suspension spring 24 forms a closed ring around the piston rod 12. It does not fall off and fall off. Further, the suspension spring 24 is provided with a spring seat rubber 30.
And the piston rod 12 together with the spring seat 22
Even if it falls around, the spring seat rubber 30 and the spring seat 22 holding the suspension spring 24 both form a closed loop around the piston rod 12, so that they come off from around the piston rod 12 and fall off. Nothing.

Since the spring holding portions 37 are dispersedly arranged at a plurality of positions in the circumferential direction of the spring seat rubber 30, the weight of the spring seat rubber 30 can be reduced as compared with the case where the spring holding portions 37 are continuously arranged on the entire circumference in the circumferential direction.

The spring holding portion 37 is replaced with the inner holding portion 38.
And the outer holding portion 39, the suspension spring 24 is firmly held so as to be gripped from inside and outside, and the back surface of the inner holding portion 38 is reinforced by the reinforcing portion 45, so that the holding strength of the suspension spring 24 can be enhanced.

Since the lightening portion 46 is provided in the reinforcing portion 45 of the inner holding portion 38, while having the above-described reinforcing effect,
The weight of the spring seat rubber 30 can be reduced.

The outer surface of the outer holding portion 39 is provided with a diameter smaller than the outer diameter of the spring seat rubber 30 which is fitted and held in the spring seat 22.
A gap is formed between the outer spring 39 and the outer surface of the outer holding portion 39, so that the outer holding portion 39 holds the end of the suspension spring 24 without a gap under the state where the suspension spring 24 is assembled into the spring seat rubber 30. When the end is positioned at a position corresponding to the reduced diameter portion of the outer holding portion 39, the displacement of the end in the radially expanding direction due to the compression deformation of the suspension spring 24 is limited to the range of the gap. Surely acceptable within

Since the dust cover 33 is integrated with the spring seat rubber 30, the number of parts can be reduced.
The number of steps for attaching the dust cover 33 around the piston rod 12 can be reduced, and the productivity of the hydraulic shock absorber can be improved.

(Second Embodiment) (FIG. 4) The spring seat rubber 50 of the second embodiment is different from the spring seat rubber 30 of the first embodiment in that the annular member 31 of the spring seat rubber 50 has a dust cover. , A separate dust cover is integrated with, for example, the bump rubber 25, and extends under the enlarged outer diameter portion on the upper end side of the dust cover so that the reduced diameter inner diameter portion 51 (outside) can be overlapped and arranged. (Blocking the water scattering path) is provided on the inner periphery of the annular body 31.

Similar to the spring seat rubber 30, the spring seat rubber 50 has a retaining hole 22A of the spring seat 22, a locking projection 34 retained on the retaining surface 22B, an outer diameter portion 35, A spring seating portion 36 for the spring 24 and a spring holding portion 37 (an inner holding portion 38 and an outer holding portion 39) are provided. Further, the spring seat rubber 50 has a protruding restraining portion 41 outside the outer holding portion 39, a centering portion 42 on the spring seating portion 36, and a part of the outer peripheral surface of the annular body 31, similarly to the spring seat rubber 30. Is provided with an alignment projection 43.

The spring seat rubber 50 has the same reinforcing portion 5 as the inner holding portion 38 of the spring seat rubber 30.
2 is provided on the back surface of the inner holding portion 38 of the spring holding portion 37. The reinforcing portion 52 includes a plate-like horizontal portion 52A extending horizontally from the lower end of the back surface of the inner holding portion 38 to the above-described reduced diameter inner portion 51, and a plate-like horizontal portion 52A from both side ends of the back surface of the inner holding portion 38 to the reduced diameter inner diameter portion 51. The inner holding portion 38, the horizontal portion 52A, and the triangular portion 52B form a concave hollow portion 53, which comprises a vertically extending plate-like substantially triangular portion 52B.

Therefore, even in the hydraulic shock absorber 10 employing the spring seat rubber 50, the piston rod 12
A thrust bearing 23 is fixed to the vehicle body-side mounting bracket 14 installed by light press fitting or the like, and a spring seat 22 is fixed to the thrust bearing 23 by light press fitting or the like. The spring seat rubber 50 is fixedly held, and the element wire at the upper end of the suspension spring 24 is restrained and used by the spring holding portions 37 (the inner holding portion 38 and the outer holding portion 39) of the spring seat rubber 50 for use. Thus, the same operation as in the first embodiment is achieved.

Although the embodiments of the present invention have been described in detail with reference to the drawings, the specific structure of the present invention is not limited to the embodiments, and the design may be changed without departing from the scope of the present invention. The present invention is included in the present invention.

[0042]

As described above, according to the present invention, in the hydraulic shock absorber, even if the suspension spring is broken, it is possible to prevent the suspension from coming off around the piston rod and falling off.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part showing a hydraulic shock absorber.

FIG. 2 is a sectional view showing a spring seat rubber according to the first embodiment.

FIG. 3 shows a spring seat rubber, and (A)
Is a bottom view showing the outer peripheral side portion of the spring seat rubber cut out, (B) is a sectional view taken along the line BB of (A),
(C) is an arrow view along line C in (A).

FIG. 4 is a cross-sectional view illustrating a spring seat rubber according to a second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Hydraulic shock absorber 11 Outer tube (damper tube) 12 Piston rod 22 Spring seat 22A Holding hole (Spring seat rubber holding means) 22B Holding surface (Spring seat rubber holding means) 24 Suspension spring 30, 50 Spring seat rubber 32 Connecting part 33 Dust cover 36 Spring seating part 37 Spring holding part (spring holding means) 38 Inner holding part 39 Outer holding part 39A Outer surface 45, 52 Reinforcement part 46, 53 Lightening part

Continuation of the front page (72) Inventor Kenji Ishikawa 1-14-1, Fujiwara-cho, Gyoda-shi, Saitama F-term in the Showa Saitama headquarters factory (reference) 3D001 AA02 AA17 AA18 BA02 CA01 DA01 3J069 AA50 CC01

Claims (6)

[Claims] 1. A structure for preventing a suspension spring from dropping out of a hydraulic shock absorber in which a suspension spring is supported via a spring seat rubber on an upper spring seat that supports a suspension spring of a hydraulic shock absorber, wherein spring seat rubber holding means is provided on the spring seat. A suspension spring drop-off prevention structure for a hydraulic shock absorber, wherein a spring holding means is provided on the spring seat rubber. 2. The suspension spring drop-off prevention structure for a hydraulic shock absorber according to claim 1, wherein said spring holding means is provided at a plurality of positions along a circumferential direction of a spring seating portion provided on a spring seat rubber. 3. The spring holding means has an inner holding portion for holding the strand of the suspension spring from the inside and an outer holding portion for holding the wire from the outside, and a reinforcing portion is attached to a back surface of the inner holding portion. Item 3. A structure for preventing a suspension spring from falling off of a hydraulic shock absorber according to Item 1 or 2. 4. A lightening portion provided in the reinforcing portion.
4. The suspension spring falling-off preventing structure of the hydraulic shock absorber according to the item 1. 5. An outer surface of the outer holding portion is provided with a reduced diameter relative to an outer diameter of the spring seat rubber which is fitted and held in a spring seat, and is provided between the spring seat and the outer surface of the outer holding portion. The suspension spring falling-off prevention structure for a hydraulic shock absorber according to claim 3, wherein a gap is formed. 6. The suspension spring falling-off prevention structure for a hydraulic shock absorber according to claim 1, wherein a dust cover is integrated with the spring seat rubber via a connecting portion.