JPH09210115A - Hydraulic dumper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid the increase of weight and reduce the cost of manufacturing by forming a string dumper having a nackle bracket at the lower end, for a wheel support member of a vehicle. SOLUTION: A hydraulic dumper comprises a nackle bracket 3 fixed to the lower end outer periphery of a outer sleeve 2 disposed outside of a dumper cylinder 1, the lower end inner periphery of the sleeve 2 having a reinforcement member 5 opposed to the upper end of the nackle bracket 3, the upper end of the reinforcement member 5 is extending a specified length from the upper end of the nackle bracket 3. In this case the lower end of the reinforcement member 5 is separated from the upper end of the lower cap 4 which closes the lower end of the sleeve 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a strut type hydraulic shock absorber for a vehicle having a knuckle bracket on the lower end side.

[0002]

2. Description of the Related Art Various strut-type hydraulic shock absorbers for vehicles having a knuckle bracket on the lower end side have been proposed in the past, but generally there are hydraulic shock absorbers of this type. Since this is a wheel support member, not only bending deformation inside the shock absorber body is prevented but also so-called external bending deformation between the shock absorber body and the knuckle bracket is prevented. Is set as follows.

That is, even if bending stress is concentrated on the contact portion of the outer cylinder forming the shock absorber body with the upper end of the knuckle bracket, the bending deformation of the outer cylinder at the contact portion is prevented.

For example, in the hydraulic shock absorber shown in FIG. 9, a vehicle is provided on the outer circumference of a lower end portion of an outer cylinder 2 which is arranged on the outer peripheral side of a damper cylinder 1 which constitutes the shock absorber main body and also constitutes the shock absorber main body. It is assumed that the knuckle bracket 3 connected to the wheel (not shown) side is fixedly installed.
An extension cylinder 4a of a lower cap 4 that closes the lower end of the outer cylinder 2 is adjacent to the inner circumference of the lower end of the.

Incidentally, the upper end of the extension cylinder portion 4a is projected from the upper end position of the knuckle bracket 3 to an appropriate length.

Therefore, in the hydraulic shock absorber according to the proposal, the lower end of the outer cylinder 2 is the extension cylinder 4a of the lower cap 4.
Therefore, it is reinforced from the inner peripheral side to a so-called lining state, and therefore, bending stress is concentrated on a portion where the upper end of the knuckle bracket 3 of the outer cylinder 2 comes into contact, that is, a portion P shown by a black dot in FIG. However, bending is less likely to occur in the portion P.

However, in the above-mentioned conventional proposals, there is a fear that the versatility of the hydraulic shock absorber cannot be expected to be improved.

That is, in the above conventional proposal, the outer cylinder 2
In order to reinforce the lower end portion of the lower cap 4 from the inner peripheral side, it is set to use the extension cylinder portion 4a of the lower cap 4. Therefore, the lower cap 4 has the extension cylinder portion 4a having a considerable length. It will be formed in a cylindrical shape.

Therefore, the above-mentioned conventional proposal has an advantage that the number of parts can be reduced because only one part is required, but the so-called effective part in which the extension cylinder part 4a reinforces the lower end part of the outer cylinder 2 from the inner peripheral side. In addition to the above, there is formed a so-called connecting portion that connects the effective portion and the cap portion that closes the lower end of the outer cylinder 2, and as a result, the connecting portion that is originally unnecessary from the viewpoint of reinforcement. Therefore, the weight of the hydraulic shock absorber is increased.

Further, since the lower cap 4 has the above-mentioned connecting portion, not only the material cost and the processing cost are increased, but also the component cost is increased, resulting in the hydraulic shock absorber as a product. This will hinder the reduction of manufacturing cost.

From the above, in the above-mentioned conventional proposals, it cannot be expected that the versatility of the hydraulic shock absorber will be improved.

The present invention was devised in view of the above-mentioned circumstances, and an object thereof is to prevent an increase in weight and to reduce the manufacturing cost, and to make the knuckle on the lower end side. (EN) Provided is a strut-type hydraulic shock absorber which has a bracket and is optimal for a vehicle.

[0013]

In order to achieve the above-mentioned object, the structure of the present invention is such that a knuckle bracket is fixedly provided on the outer periphery of the lower end portion of an outer cylinder arranged on the outer peripheral side of the damper cylinder. A hydraulic shock absorber having a reinforcing member facing the upper end of the knuckle bracket on the inner periphery of the lower end of the outer cylinder, and the upper end of the reinforcing member being protruded to an appropriate length from the upper end position of the knuckle bracket, The lower end of the reinforcing member is separated from the upper end of the lower cap that closes the lower end of the outer cylinder.

In this case, the reinforcing member may be made of a pipe material or a plate-wound pipe material and press-fitted into the inner circumference of the lower end portion of the outer cylinder, or the reinforcing member may be made of pipe material and arranged from the outer peripheral side of the outer cylinder. It may be held in the outer cylinder by deformation processing by roll crimping or punch crimping.

When press-fitting the pipe material, a pipe material having an outer diameter larger than the inner diameter of the outer cylinder may be forcedly inserted from above or below the outer cylinder, or a pipe material having an outer diameter smaller than the inner diameter of the outer cylinder. May be arranged on the inner peripheral side of the outer cylinder, and then the outer cylinder may be drawn until the inner peripheral surface of the outer cylinder comes into close contact with the outer peripheral surface of the pipe material. Further, when the pipe material is fixed to the outer cylinder, it is preferable to continuously connect the outer cylinder to the outer cylinder by arc spot welding or spot welding from the outer peripheral side of the outer cylinder.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described based on the illustrated embodiments. As shown in FIG. 1, a hydraulic shock absorber according to an embodiment of the present invention includes a damper cylinder 1 A knuckle bracket 3 is fixedly provided on the outer circumference of the lower end portion of the outer cylinder 2 arranged on the outer circumference side.

The damper cylinder 1 and the outer cylinder 2 constitute a shock absorber body, and a reservoir chamber R communicating with the inside of the damper cylinder 1 is formed between them, and the knuckle bracket 3 is formed.
Is a connecting member for connecting the lower end side of the shock absorber main body to a wheel side (not shown) of the vehicle, and has a mounting hole 3b in a mounting portion 3a on the wheel side.

The hydraulic shock absorber has a pipe-shaped reinforcing member 5 facing the upper end of the knuckle bracket 3 on the inner periphery of the lower end of the outer cylinder 2, and the upper end of the reinforcing member 5 has the knuckle bracket 3 at its upper end. The length L is appropriately projected from the upper end position of the.

The upper end of the reinforcing member 5 is the knuckle bracket 3.
The reason why the reinforcing member 5 is projected to the length L from the upper end position is that the bending stress is concentrated on a portion where the reinforcing member 5 is shown by a black dot in FIG. 1, that is, a portion P where the upper end of the knuckle bracket 3 of the outer cylinder 2 contacts. However, this is because bending of the shock absorber main body at the portion P is less likely to occur.

The reinforcing member 5 is arranged on the inner periphery of the lower end portion of the outer cylinder 2, and in the illustrated embodiment, it is arranged by press fitting from below or above the outer cylinder 2. Therefore, by press-fitting the reinforcing member 5, the inner circumference of the lower end portion of the outer cylinder 2 is reinforced from the inner circumference side to a so-called lining state. When the reinforcing member 5 is press-fitted into the outer cylinder 2, the outer diameter b of the reinforcing member 5 is made larger than the inner diameter a of the outer cylinder 2 so that the difference (b to a) between the two.
Is preferably about 0 to 0.2 mm.

In the hydraulic shock absorber, the lower end of the reinforcing member 5 is separated from the upper end of the lower cap 4 that closes the lower end of the outer cylinder 2, and in the illustrated embodiment, There is an appropriate gap between the lower end of the reinforcing member 5 and the upper end of the lower cap 4.

That is, when the lower cap 4 functions as a lower cap and the reinforcing member 5 functions as a reinforcing member, in the above-mentioned conventional proposal, a so-called unnecessary portion is formed as a connecting portion between the cap portion and the effective portion. There is a length interval corresponding to the length of the region.

By separating the reinforcing member 5 from the lower cap 4 so as to have an appropriate space, the hydraulic shock absorber corresponding to the above-mentioned unnecessary portion is compared with the above-mentioned conventional example. It is possible to prevent the increase of the weight in.

Then, the reinforcing member 5 and the lower cap 4
By separating and, each so-called assembling work is simplified, and compared with the above-mentioned conventional example,
For example, the fear of alienating the smooth flow of the assembly line is eliminated.

In the illustrated embodiment, the reinforcing member 5 is made of a member sufficient to function as a reinforcing member, for example, a metal pipe material. As long as it is reinforced from the side to a so-called backing state, instead of being made of a pipe material, as shown in FIG. 2, a flat plate is formed into a cylindrical shape and made of a plate-wound pipe material having seams 5a. Is also good.

When a plate-wound pipe material is used for the reinforcing member 5, it is possible to reduce the diameter of the reinforcing member 5 corresponding to the width of the seam 5a with elasticity, and thus the outer cylinder 2
The operation of distributing the reinforcing member 5 to the inner peripheral side of the outer cylinder 2 is facilitated while ensuring the adhesion to the inner peripheral side.

When a plate-wound pipe material is used for the reinforcing member 5, the reinforcing member 5 made of the plate-wound pipe material can be used even when the inner diameter of the outer cylinder 2 is slightly increased. It becomes possible to meet the request for standardization or conversion of parts.

Incidentally, the reinforcing member 5 made of a plate-wound pipe material.
As shown in FIG. 3, when distributing the outer cylinder 2 to the inner circumference of the outer cylinder 2,
It is preferable to consider so that the distribution position of the seam 5a is a so-called 45 degree position.

That is, in the case of a strut type hydraulic shock absorber, in general, when the right side is the center side of the vehicle and the left side is the side side of the vehicle in FIG. 3, the position indicated by the black dot in FIG. The bending stress is concentrated on the above-mentioned structure. Therefore, it is preferable that the seam 5a does not face the position where the bending stress is concentrated.
It is preferable that the seam 5a be positioned at a so-called 45 degree position shown by an imaginary line.

By the way, as to the upper end of the reinforcing member 5, it is a curved end toward the inner peripheral side as shown by a virtual diagram in FIG. 1, or a bent end (not shown). Also good.

In this case, the operability when press-fitting the reinforcing member 5 from below the outer cylinder 2, that is, the insertability is improved, and the upper end of the knuckle bracket 3 of the outer cylinder 2 is adjacent to the portion P. When a bending load acts on (see FIG. 1), stress concentration at that time can be avoided by distributing the load, and the fatigue strength of the portion P can be substantially improved.

On the other hand, in the distribution of the reinforcing member 5 to the inner circumference of the outer cylinder 2, after the press-fitting or instead of the above-mentioned press-fitting, the caulking method shown in FIGS. 4 and 5 or the welding method shown in FIG. It may be adopted, and in the case of crimping or welding, reliability of the fixing property of the reinforcing member 5 at a predetermined position can be easily obtained.

To explain a little, in FIG. 4, the outer cylinder 2 and the reinforcing member 5 are simultaneously deformed by roll caulking from the outer peripheral side of the outer cylinder 2 in the circumferential direction of the outer cylinder 2 to form the outer cylinder 2 with the outer cylinder. Two
An embodiment is shown in the case of holding it on the inner circumference.

In this case, the deformed projecting end 5b of the reinforcing member 5 faces the outer periphery of the damper cylinder 1 existing on the inner peripheral side of the reinforcing member 5 with an appropriate interval. Needless to say, it is maintained so that the reservoir chamber R (see FIG. 1) is not divided.

Instead of the roll caulking, punch caulking may be used. In the case of the punch caulking, as shown in FIG. 5, an appropriate interval in the circumferential direction of the outer cylinder 2, for example, 90 degree intervals shown in the figure. Then, the punch caulking is applied.

And, in the case of the punch caulking,
It is preferable that the deformed projecting end 5b of the reinforcing member 5 is embodied in a state of being brought into contact with the outer periphery of the damper cylinder 1 existing on the inner peripheral side of the reinforcing member 5. In this case, a plurality of The protruding end 5b facilitates centering when the damper cylinder 1 is distributed.

As the reinforcing member 5 held on the inner circumference of the outer cylinder 2 by the above-mentioned deformation processing by caulking, the joint 5a is formed.
It goes without saying that a normal pipe material is used instead of the plate-wound pipe material (see FIG. 2) having the above.

Of course, the upper end of the reinforcing member 5 may be a curved end toward the inner peripheral side or a bent end.

FIG. 6 shows an embodiment in which the reinforcing member 5 is welded from the outer peripheral side of the outer cylinder 2, that is, is connected to the outer cylinder 2 by arc spot welding. When doing, an appropriate interval in the circumferential direction of the outer cylinder 2,
For example, welding holes (not shown) are opened at intervals of 90 degrees, the molten welding metal M is filled in the welding holes, and the reinforcing member 5 is held on the inner circumference of the outer cylinder. Is.

In the case of the welding, the reliability of the fixing property of the reinforcing member 5 to the inner circumference of the outer cylinder 2 is improved as compared with the case of the above-mentioned caulking.

Although not shown, spot welding may be used instead of the arc spot welding. In the case of the spot welding, for welding to the outer cylinder 2 which is essential in the case of the arc spot welding described above. This is advantageous in that work for opening holes is omitted and workability is improved.

As the reinforcing member 5 which is held on the inner circumference of the outer cylinder 2 by the above welding, it goes without saying that a normal pipe material may be used together with the plate-wound pipe material having the seam 5a.

Of course, the upper end of the reinforcing member 5 may be a curved end toward the inner peripheral side or a bent end.

FIGS. 7 and 8 show another embodiment of the present invention. As shown in FIG. 7, this is a reinforcement made of a pipe material having an outer diameter d1 smaller than the inner diameter D1 of the outer cylinder 2. The member 5 is inserted into the outer cylinder 2, and then the outer cylinder 2 is drawn to bring the inner circumference of the outer cylinder 2 into close contact with the outer circumference of the reinforcing member 5 as shown in FIG. Spot welding is used.

More specifically, the outer diameter of the outer cylinder 2 is D
0, the inner diameter is D1, and the outer diameter of the reinforcing member 5 is d1, D
1> d1, the outer diameter reduction amount (D0 to D1) is D0 to D1 ≧ D1 to d1, and the outer diameter of the outer cylinder 2 after the reduction is
It becomes D01.

As shown in FIG. 7, with the lower cap 4 attached, the reinforcing member 5 made of a pipe material is inserted into the outer cylinder 2 from above the outer cylinder 2, and the inner periphery of the reinforcing member 5 is jigged. The outer cylinder 2 is drawn while being supported by, for example, and the inner circumference of the outer cylinder 2 is brought into close contact with the outer circumference of the reinforcing member 5. This state is the same as the state where the reinforcing member 5 is press-fitted into the outer cylinder 2.

However, in the mounting method of the reinforcing member 5 by drawing the outer cylinder 2, as compared with the simple press-fitting method of the reinforcing member, the occurrence of galling is prevented, and the dimensional relationship of the outer cylinder 2 with respect to the reinforcing member 5 is prevented. Can be roughened, and the drawn portion of the outer cylinder 2 becomes a compressive stress to improve bending fatigue, the dimensional accuracy of the outer cylinder 2 corresponding to the insertion portion of the knuckle bracket 3 is improved, and the inner circumference of the outer cylinder 2 is reduced. Adhesion to the outer periphery of the reinforcing member 5 is improved, whereby both can be integrally deformed and bending rigidity is improved.

After mounting the reinforcing member 5 in the outer cylinder 2,
As in the case of FIG. 6, it is preferable to perform arc spot welding using the weld metal M.

[0049]

According to the invention of each claim, there are the following effects.

Since the reinforcing member disposed on the inner circumference of the lower end portion of the outer cylinder is separated from the lower cap that closes the lower end of the outer cylinder, the reinforcing member is provided with the lower cap by appropriately setting the separation interval. It is possible to prevent the weight of the hydraulic shock absorber from increasing as compared with the case where the hydraulic shock absorber is integrally connected to the hydraulic shock absorber. By separating the reinforcing member and the lower cap, each so-called assembling work is simplified, and for example, the fear of alienating the smooth flow of the assembly line is eliminated.

According to the second aspect of the invention, the reinforcing member is press-fitted into the inner circumference of the lower end portion of the outer cylinder, which is advantageous in terms of workability.

According to the third aspect of the present invention, since the reinforcing member disposed on the inner circumference of the lower end portion of the outer cylinder is held by the outer cylinder by caulking, the fixing property of the reinforcing member to the outer cylinder is excellent. Further, when welding is used instead of caulking, the reliability of the fixing property is further improved.

In the invention of each claim, when the reinforcing member is made of a plate-wound pipe material having a seam instead of the ordinary pipe material, the reinforcing member corresponding to the width of the seam. Therefore, it is possible to reduce the diameter with elasticity, and therefore, while ensuring the adhesion to the inner circumference of the outer cylinder, the operation of distributing the reinforcing member to the inner circumference of the outer cylinder is facilitated. Similarly, when a plate-wound pipe material is used as the reinforcing member, the reinforcing member made of the plate-wound pipe material can be used even when the inner diameter of the outer cylinder is slightly increased. It can respond to requests for standardization or diversion.

In the invention of each claim, when the upper end of the reinforcing member is a curved end to the inner peripheral side or a bent end, the insertability when press-fitting the reinforcing member from the lower end of the outer cylinder is improved. While being improved, when a bending load acts on the part where the upper end of the knuckle bracket in the outer cylinder is adjacent,
It is possible to avoid stress concentration at that time by dispersing the load, and it is possible to substantially improve the fatigue strength in the above-mentioned portion.

According to the inventions of the respective claims, even if the bending stress is concentrated on a portion adjacent to the upper end of the knuckle bracket in the outer cylinder constituting the shock absorber body, the bending deformation is not caused to the portion. That is, it is possible to prevent an increase in weight and reduce the manufacturing cost, and it is optimal to provide a strut type hydraulic shock absorber for a vehicle having a knuckle bracket on the lower end side.

According to the invention of claim 5, the following effects can be obtained.

1 / There is no reduction in galling when the reinforcing member is inserted into the outer cylinder, and as a result, galling can be prevented from occurring.

2 / It is possible to roughen the size of the outer cylinder with respect to the reinforcing member, and the processing cost becomes effective. Moreover, since the outer diameter of the knuckle bracket can be adjusted by drawing each time, the dimensional accuracy can be improved and the cost can be reduced.

3 / Since the outer diameter of the outer cylinder is narrowed, the narrowed portion becomes a compressive stress, and bending fatigue is improved.

4 / The outer cylinder can be drawn to be in close contact with the outer periphery of the reinforcing member, so that the degree of close contact between the two is improved, and when a bending load is applied, both are deformed as a unit and rigidity is improved. To do.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view showing a strut-type hydraulic shock absorber according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a reinforcing member according to another embodiment.

3 is a cross-sectional view showing a state in which the reinforcing member shown in FIG. 2 is arranged on the inner circumference of an outer cylinder.

FIG. 4 is an enlarged partial sectional view showing an embodiment in which a reinforcing member is held on the inner circumference of an outer cylinder by roll caulking.

FIG. 5 is an enlarged cross-sectional view showing an embodiment in which a reinforcing member is held by punch caulking on the inner circumference of an outer cylinder.

FIG. 6 is an enlarged partial sectional view showing an embodiment in which a reinforcing member is held on the inner circumference of an outer cylinder by arc spot welding in the same manner as in FIG.

FIG. 7 is an enlarged partial sectional view according to another embodiment showing an arrangement state of an outer cylinder and a reinforcing member before performing a drawing process.

FIG. 8 is a partially enlarged cross-sectional view according to another embodiment showing a state where the outer cylinder is brought into close contact with the reinforcing member by drawing.

FIG. 9 is a front view showing a strut type hydraulic shock absorber as a conventional example with a part thereof cut away similarly to FIG. 1.

[Explanation of symbols]

 1 Damper Cylinder 2 Outer Cylinder 3 Knuckle Bracket 4 Lower Cap 5 Reinforcing Member 5a Seam in Plate-wound Pipe Material as Reinforcing Member D1 Inner Diameter of Outer Tube d1 Outer Diameter of Pipe Material as Reinforcing Member

 ─────────────────────────────────────────────────── --- Continuation of the front page (72) Inventor Shinichi Sugioka 2-4-1 Hamamatsucho, Minato-ku, Tokyo World Trade Center Building Kayaba Industry Co., Ltd. (72) Inventor Tadaaki Koto 2-chome, Hamamatsucho, Minato-ku, Tokyo 4th-1 World Trade Center Building Kayaba Industry Co., Ltd.

Claims (6)

[Claims] 1. A reinforcing member, wherein a knuckle bracket is fixedly provided on an outer periphery of a lower end portion of an outer cylinder arranged on an outer peripheral side of a damper cylinder, and an inner periphery of a lower end portion of the outer cylinder faces an upper end portion of the knuckle bracket. And a lower end of the reinforcing member is separated from an upper end of a lower cap closing the lower end of the outer cylinder. A hydraulic shock absorber characterized in that 2. The hydraulic shock absorber according to claim 1, wherein the reinforcing member is made of a pipe material or a plate-wound pipe material and is press-fitted into the inner circumference of the lower end portion of the outer cylinder. 3. The hydraulic shock absorber according to claim 1, wherein the reinforcing member is made of a pipe material and is held by the outer cylinder by a deformation process by roll caulking or punch caulking performed from the outer peripheral side of the outer cylinder. 4. The hydraulic shock absorber according to claim 2, wherein a pipe material having an outer diameter larger than the inner diameter of the outer cylinder is forcibly inserted from above or below the outer cylinder. 5. A pipe material having an outer diameter smaller than the inner diameter of the outer cylinder is arranged on the inner peripheral side of the outer cylinder, and then the outer cylinder is drawn until the inner peripheral surface of the outer cylinder comes into close contact with the outer peripheral surface of the pipe material. The hydraulic shock absorber according to claim 2. 6. The hydraulic shock absorber according to claim 1, wherein the reinforcing member is made of a pipe material or a plate-wound pipe material, and is continuously connected to the outer cylinder by arc spot welding or spot welding from the outer peripheral side of the outer cylinder.