JP4156201B2 - Structure to prevent the suspension spring from falling off - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a structure for preventing a suspension spring from falling off a hydraulic shock absorber.
[0002]
[Prior art]
Conventionally, a hydraulic shock absorber has a tamper tube and a piston rod as described in Japanese Utility Model Publication No. 53-9615, a spring seat is provided on the piston rod, and a suspension spring is provided on the spring seat via a spring seat rubber. I support it.
[0003]
[Problems to be solved by the invention]
However, in the prior art, when the suspension spring breaks, the suspension spring is entangled with the piston rod from the upper and lower ends or the cut end, and then the suspension spring rotates and slides with respect to the piston rod. There is a risk of falling off from the surroundings. The dropped suspension spring may come into contact with the tire.
[0004]
An object of the present invention is to prevent a hydraulic shock absorber from falling off from around the piston rod even if the suspension spring is broken.
[0005]
[Means for Solving the Problems]
According to a first aspect of the present invention, there is provided a suspension mechanism for preventing a spring spring from falling off in a suspension system for a hydraulic shock absorber in which a suspension spring is supported by an upper spring seat supporting a suspension spring of the hydraulic shock absorber via a spring seat rubber. The spring seat rubber is provided with spring holding means, and the spring holding means has an inner holding part for holding the wire of the suspension spring from the inside and an outer holding part for holding from the outside, and the inner holding part. Is provided with a reinforcing portion on the back surface, the reinforcing portion is a plate-like horizontal portion extending horizontally from the lower end portion of the back surface of the inner holding portion, and a concave shape formed on the back surface of the inner holding portion and above the plate-like horizontal portion. and a thin portion, der those wherein the inner holding portion is an upper portion of the plate-shaped horizontal section, and so that a thin walled walls of thicker than the other portion which holds the strand .
[0006]
According to a second aspect of the present invention, in the first aspect of the present invention, the protruding restraint portion that further contacts the outer surface of the outer holding portion of the spring seat rubber without any gap on the outer side in the radial direction of the thin wall portion, The outer surface of the outer holding portion is provided with a reduced diameter, and a clearance formed between the spring seat and the outer surface of the outer holding portion is provided .
[0007]
According to a third aspect of the present invention, in the first or second aspect of the present invention, the thin wall portion does not contact the spring seat .
[0017]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a cross-sectional view of a main part showing a hydraulic shock absorber, FIG. 2 is a cross-sectional view showing a spring seat rubber of the first embodiment, FIG. 3 shows a spring seat rubber, and FIG. Cut-out bottom view, (B) is a cross-sectional view taken along line BB in (A), (C) is a view taken in the direction of arrow C in (A), and FIG. 4 is a spring seat rubber according to the second embodiment. FIG.
[0018]
First Embodiment (FIGS. 1 to 3)
The hydraulic shock absorber 10 is a strut damper type, and, as shown in FIG. 1, a piston rod 12 is inserted into a cylinder (not shown) built in the outer tube 11 (damper tube), and attached to the outer tube 11 on the wheel side. A bracket 13 is provided to be coupled to the wheel, and a piston rod 12 protruding from the outer tube 11 is provided with a vehicle body side mounting bracket 14 to be attached to the vehicle body. The vehicle body side mounting bracket 14 includes a mount rubber assembly 18 including a collar 15, upper and lower mount bases 16 </ b> A and 16 </ b> B, and a mount rubber 17. The collar 15 of the mount rubber assembly 18 is connected to the upper end side small diameter of the piston rod 12. It is configured by being inserted into the part and fastened with a nut 19.
[0019]
The hydraulic shock absorber 10 includes a tie rod mounting arm 20 connected to the outer tube 11 and is connected to the tie rod, and transmits a steering force by a steering device (not shown) from the outer tube 11 to a wheel so that the steering can be performed.
[0020]
The hydraulic shock absorber 10 has a lower spring seat 21 fixed to the outer periphery of the outer tube 11 and a thrust bearing 23 installed around the piston rod 12 and fixed to the vehicle body side mounting bracket 14 by light press-fitting or the like and supported on the back surface. A suspension spring 24 is interposed between the upper spring seat 22 fixed by light press fitting or the like. Specifically, the suspension spring 24 is supported by the lower spring seat 21 and supported by the upper spring seat 22 via the spring seat rubber 30.
[0021]
The hydraulic shock absorber 10 includes a bump rubber 25 that is inserted so as to be firmly held below the vehicle body side mounting bracket 14 of the piston rod 12. The hydraulic shock absorber 10 abuts the bump rubber 25 on the bump stopper cap 26 on the upper end surface of the outer tube 11 and restricts the maximum compression stroke at the time of maximum compression.
[0022]
In other words, the hydraulic shock absorber 10 expands and contracts so that the impact force that the vehicle receives from the road surface is absorbed by the elastic force of the suspension spring 24. The hydraulic shock absorber 10 has its expansion and contraction vibrations due to a damping force generated by a piston valve device provided in the piston, a base valve device provided in the cylinder, and the like when a piston (not shown) moves up and down accompanying the expansion and contraction. Is quickly suppressed.
[0023]
However, the hydraulic shock absorber 10 includes a spring seat rubber 30 for supporting the suspension spring 24 on the upper spring seat 22 as shown in FIGS.
[0024]
The spring seat rubber 30 is integrally formed with a bellows-like dust cover 33 via an annular coupling portion 32 provided on the inner periphery of the annular body 31. The lower end portion of the dust cover 33 can be brought into contact with a dust cover receiver 26 </ b> A provided on the bump stopper cap 26.
[0025]
The spring seat rubber 30 has holding holes 22A provided at a plurality of circumferential positions (four positions in the present embodiment) on the upper surface of the annular body 31 at a plurality of circumferential positions (four positions in the present embodiment) of the spring seat 22. Is provided with a locking projection 34 that is elastically deformed and press-fitted and locked, and is press-fitted into the holding surface 22B provided inside the outer peripheral wall of the spring seat 22 and fitted and held on the outer periphery of the annular body 31. The fitting outer diameter part 35 is provided. Thereby, 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 a spring seat rubber holding means.
[0026]
The spring seat rubber 30 is provided with a spring seat portion 36 having a concave cross section that is continuous in the circumferential direction on the lower surface of the annular body 31, and a strand on the upper end side of the suspension spring 24 is seated on and supported by the spring seat portion 36. The spring seat rubber 30 is provided with spring holding portions 37 at a plurality of positions (four positions in the present embodiment) along the circumferential direction of the spring seating portion 36 over a certain length range along the circumferential direction. The spring holding portion 37 includes an inner holding portion 38 that holds the wire on the upper end portion side of the suspension spring 24 from the inside, and an outer holding portion 39 that holds the wire from the outside, and the inner holding portion 38 and the outer holding portion. 39 is used to form a wire gripping surface 40 that grips and holds a range exceeding 180 degrees on the outer periphery of the cross section of the wire of the suspension spring 24 (FIG. 2).
[0027]
The spring seat rubber 30 is provided so that the outer surface 39A of the outer holding portion 39 is 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 (FIG. 3A) is formed between the surface 22 </ b> B and the outer surface 39 </ b> A of the outer diameter holding portion 39. The spring seat rubber 30 includes a protruding restraining portion 41 that is in contact with the holding surface 22B of the spring seat 22 without a gap on the outside of the outer shape holding portion 39, and restrains the radial position of the suspension spring 24 held by the outer holding portion 39. To do. In addition, the spring seat rubber 30 has a wire on the upper end side of the suspension spring 24 extending from the outer peripheral side to a central portion sandwiched between adjacent spring holding portions 37, 37 along the circumferential direction of the spring seat portion 36. A projecting centering portion 42 that restrains and centers the entire suspension spring 24 with respect to the spring seat rubber 30 is provided. The outer peripheral surface of the strand of the suspension spring 24 centered by the centering portion 42 is a gap between the spring seating portion 36 and the outer holding portion 39 and the centering portion 42 along the circumferential direction of the spring seating portion 36. B is given.
[0028]
The spring seat rubber 30 includes a range in which the above-described reduced diameter outer surface 39A of the outer holding portion 39 forms the above-described gap A between the holding surface 22B of the spring seat 22 and a spring seating portion 36 that forms the above-described gap B. When the upper end portion of the strand of the suspension spring 24 (the cut end surface of the strand) is positioned at a position corresponding to the range to be expanded, the displacement of the upper end portion due to the compression deformation of the suspension spring 24 in the diameter-expanding direction is changed between the gaps. It is acceptable within the range of A and B. Note that the mounting position of the suspension spring 24 to the spring seat 22 is determined at the mounting stage. For this reason, when the spring seat rubber 30 is assembled so that the suspension spring 24 is seated on the spring seat portion 36, the position of the upper end portion of the strand of the suspension spring 24 is within a range in which the gaps A and B are formed. The spring seat 22 (on the outer surface of the projecting restraint portion 41 provided outside the outer holding portion 39 in the present embodiment) is arranged on a part of the outer peripheral surface of the annular body 31 so as to be set to a corresponding proper assembly position. An alignment projection 43 to the holding surface 22B) is provided. By engaging the alignment protrusion 43 of the spring seat rubber 30 with an alignment recess (not shown) provided on the holding surface 22 </ b> B of the spring seat 22, the suspension spring 24 that is attached to a normal attachment position to the spring seat 22. The upper end portion of the element wire can be positioned at the above-described proper assembly position with respect to the spring seat rubber 30.
[0029]
The spring seat rubber 30 includes a reinforcing portion 45 attached to the back surface of the inner holding portion 38 in the spring holding portion 37. The reinforcing portion 45 includes a plate-like horizontal portion 45A extending horizontally from the lower end portion on the back surface of the inner holding portion 38 to the connecting portion 32 with the dust cover 33, and the connecting portion 32 from both side end portions on the back surface of the inner holding portion 38. The plate-like substantially triangular portion 45B extending perpendicularly to the inner side of the inner holding portion 38, the horizontal portion 45A, and the triangular portion 45B form a concave hollow portion 46.
[0030]
Accordingly, in the hydraulic shock absorber 10, the thrust bearing 23 is fixed to the vehicle body side mounting bracket 14 provided on the piston rod 12 by light press fitting or the like, and the spring seat 22 is fixed to the thrust bearing 23 by light press fitting or the like. The spring seat rubber 30 is fixedly held in the holding hole 22A and the holding surface 22B of the spring seat 22, and the suspension spring 24 is attached to the spring holding portion 37 (inner holding portion 38, outer holding portion 39) of the spring seat rubber 30. The strands at the upper end of the are restrained and used.
[0031]
The hydraulic shock absorber 10 has the following effects.
(1) Even if the suspension spring 24 is damaged, the suspension spring 24 is held by the spring seat rubber 30 and does not fall off. Even if the suspension spring 24 falls together with the spring seat rubber 30 from the spring seat 22, the spring seat rubber 30 holding the suspension spring 24 forms a closed ring around the piston rod 12. It will not come off from the periphery of the rod 12 and fall off. Even if the suspension spring 24 falls around the piston rod 12 together with the spring seat rubber 30 and the spring seat 22, both the spring seat rubber 30 and the spring seat 22 holding the suspension spring 24 are closed around the piston rod 12. Since they have an annular shape, they do not fall off around the piston rod 12 and fall off.
[0032]
{Circle around (2)} 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 spring seat rubber 30 can be reduced in weight as compared with those continuously arranged on the entire circumference in the circumferential direction.
[0033]
(3) Since the spring holding portion 37 has the inner holding portion 38 and the outer holding portion 39, the suspension spring 24 is firmly held so as to be grasped from inside and outside, and the back surface of the inner holding portion 38 is reinforced by the reinforcing portion 45. Therefore, the holding strength of the suspension spring 24 can be enhanced.
[0034]
(4) Since the thinned portion 46 is provided in the reinforcing portion 45 of the inner holding portion 38, the weight of the spring seat rubber 30 can be reduced while providing the reinforcing effect (3).
[0035]
(5) The outer surface of the outer holding portion 39 is provided with a smaller diameter than the outer diameter of the spring seat rubber 30 fitted and held in the spring seat rubber 30, and between the spring seat 22 and the outer surface of the outer holding portion 39. Since the gap is formed, even when the outer holding portion 39 holds the end portion of the suspension spring 24 without any gap under the state in which the suspension spring 24 is assembled to the spring seat rubber 30, the end portion is moved to the outer side. As long as the holding portion 39 is positioned at a position corresponding to the above-mentioned reduced diameter portion, the displacement of the end portion in the diameter increasing direction due to the compressive deformation of the suspension spring 24 can be reliably allowed within the range of the gap.
(6) 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.
[0037]
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 body 31 of the spring seat rubber 50 does not have a dust cover integrally, and a separate dust cover is used, for example. A reduced diameter inner diameter portion 51 (blocking the outside water scattering path) which is integrated with the bump rubber 25 and extends below the enlarged diameter outer diameter portion on the upper end side of the dust cover so as to be overlapped with the annular body 31. Is located on the inner circumference.
[0038]
Similar to the spring seat rubber 30, the spring seat rubber 50 includes an annular body 31, a holding hole 22 </ b> A of the spring seat 22, a locking projection 34 held on the holding surface 22 </ b> B, an outer diameter portion 35, and a suspension spring 24. A spring seat 36 and a spring holder 37 (an inner holder 38 and an outer holder 39). Similarly to the spring seat rubber 30, the spring seat rubber 50 has a protruding restraint portion 41 outside the outer holding portion 39, a centering portion 42 at the spring seat portion 36, and a part of the outer peripheral surface of the annular body 31. Is provided with an alignment projection 43.
[0039]
The spring seat rubber 50 includes a reinforcing portion 52 similar to the inner holding portion 38 of the spring seat rubber 30 on the back surface of the inner holding portion 38 in the spring holding portion 37. The reinforcing portion 52 includes a plate-like horizontal portion 52A extending horizontally from the lower end portion of the back surface of the inner holding portion 38 to the aforementioned reduced diameter inner diameter portion 51, and a reduced diameter inner diameter portion 51 from both side end portions of the rear surface of the inner holding portion 38. It consists of a plate-like substantially triangular portion 52B extending vertically, and a concave hollow portion 53 is formed by the inner holding portion 38, the horizontal portion 52A, and the triangular portion 52B.
[0040]
Therefore, even in the hydraulic shock absorber 10 employing the spring seat rubber 50, the thrust bearing 23 is fixed to the vehicle body side mounting bracket 14 installed on the piston rod 12 by light press fitting or the like, and the spring seat 22 is attached to the thrust bearing 23. The spring seat rubber 50 is fixedly held in the holding hole 22A and the holding surface 22B of the spring seat 22, and the spring holding portion 37 (inner holding portion 38, outer holding) of the spring seat rubber 50 is fixed by light press fitting or the like. The wire at the upper end portion of the suspension spring 24 is restrained and used in the portion 39), and has the same effect as in the first embodiment.
[0041]
The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration of the present invention is not limited to this embodiment, and there are design changes and the like without departing from the gist of the present invention. Is included in the present invention.
[0042]
【The invention's effect】
As described above, according to the present invention, in the hydraulic shock absorber, even if the suspension spring is broken, it can be prevented from coming off from the periphery of the piston rod and falling off.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a main part showing a hydraulic shock absorber.
FIG. 2 is a cross-sectional view showing the spring seat rubber according to the first embodiment.
FIG. 3 shows a spring seat rubber, (A) is a bottom view showing the outer peripheral side portion of the spring seat rubber, (B) is a sectional view taken along line BB in (A), (C) ) Is an arrow view along the C view of (A).
FIG. 4 is a cross-sectional view showing a spring seat rubber according to a second embodiment.
[Explanation 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 springs 30 and 50 spring seat rubber 32 connecting portion 33 dust cover 36 spring seating portion 37 spring holding portion (spring holding means)
38 Inner holding part 39 Outer holding part 39A Outer surface 45, 52 Reinforcement part 46, 53 Meat removal part

Claims (3)

In the suspension structure for preventing the fall of the suspension spring of the hydraulic shock absorber supporting the suspension spring via the spring seat rubber on the upper spring seat supporting 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,
The spring holding means has an inner holding part for holding the wire of the suspension spring from the inside, and an outer holding part for holding from the outside;
The inner holding portion includes a reinforcing portion on the back surface thereof,
The reinforcing portion includes a plate-like horizontal portion that extends horizontally from the lower end of the back surface of the inner holding portion, and a concave meat-cut portion that is the back surface of the inner holding portion and is formed at the top of the plate-like horizontal portion,
The suspension mechanism for preventing a suspension spring from falling off, characterized in that the inner holding part has a thin wall part with a thinner wall than the other part holding the wire at the upper part of the plate-like horizontal part . A projecting restraint portion that is in contact with the outer surface of the outer holding portion of the spring seat rubber without gaps on the radially outer side of the thin wall portion; and
The suspension spring for a hydraulic shock absorber according to claim 1, further comprising a clearance formed between the outer surface of the outer holding portion with a reduced diameter and a spring seat and an outer surface of the outer holding portion. Drop-off prevention structure.   The suspension spring drop-off preventing structure for a hydraulic shock absorber according to claim 1 or 2, wherein the thin wall portion does not contact the spring seat.

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