JPH08210421A - Hydraulic shock absorber - Google Patents

Abstract

PURPOSE: To provide a shock absorber in which the cost reduction by the weight reduction and the curtailment of the number of parts without lowering the rigidity and the strength against the bending moment in right and left directions of a vehicle. CONSTITUTION: A fixing bracket 2 is composed of a cylinder part 21, which has partially notches wherein the bottom end part of an outside cylinder 1 is press-fit, and mounting flanges 22 and 22 extended in parallel with each other from both ends of the notches in the cylinder part 21. At the base end part of the cylinder 21 side of both mounting flanges 22 and 22 are made ribs 27 and 28, which extend the cylinder part in the direction of the notches, and the rib 27 is formed at the position upper than the center of an upper bolt insertion hole 25 at least out of the bolt insertion holes 25 and 26 made in the upper and lower two places of both mounting flanges 22 and 22.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic shock absorber, and more particularly to a technique for improving a fixing bracket structure.

[0002]

2. Description of the Related Art Conventionally, as a fixing bracket structure in such a hydraulic shock absorber, for example, an actual flat plate 1 is used.
A structure as described in Japanese Patent Publication No. 120404 is known.

The fixing bracket in this conventional hydraulic shock absorber extends parallel to each other from a cylindrical portion having a partial cutout portion along the circular outer peripheral surface of the lower end portion of the outer cylinder and both end edges of the cutout portion of the cylindrical portion. And a mounting flange portion, and a concave portion is formed in the outer cylinder at a position corresponding to the cutout portion in the cylindrical portion, and a cylindrical portion-side base end portion of both mounting flange portions is formed on the outer peripheral surface of the outer cylinder. The rib is formed so as to project in the direction of the notch while being fitted and locked in the recess.

That is, in this conventional example, the inner bracket can be omitted from the fixing bracket which has conventionally been composed of two members, the outer bracket and the inner bracket, and the cost can be reduced by reducing the number of parts. It had the advantage that

[0005]

However, the structure of the conventional hydraulic shock absorber as described above has the following problems.

That is, in the hydraulic shock absorber of the type in which the fixing bracket is attached to the unsprung side, the position where the bolt of the fixing bracket is fastened to the unsprung side is eccentric to the outside of the axial center of the hydraulic shock absorber. In addition, since the hydraulic shock absorber is attached in a state of being inclined in the left-right direction of the vehicle, a bending moment in the left-right direction acts on the lower end of the outer cylinder to which the fixing bracket is attached when bouncing the vehicle. During the pressure stroke of the hydraulic shock absorber, especially on the upper side of the fixing bracket, due to the biting of the outer cylinder, a force in the direction of increasing the distance between the two mounting flange parts is received. In the above, the concave part of the outer cylinder and the ribs that engage with the concave part are inserted through both upper and lower bolts in the fixing bracket. Since it is formed in only one place in the center of the space, it is not possible to effectively prevent biting of the outer cylinder between both mounting flange parts when a bending moment in the vehicle left-right direction acts. This allows
This will reduce the stability of the vehicle during cornering.

The present invention has been made by paying attention to the conventional problems as described above, and it is possible to reduce the cost by reducing the weight and the number of parts without lowering the rigidity and strength against the bending moment in the lateral direction of the vehicle. An object of the present invention is to provide a hydraulic buffer that can be reduced.

[0008]

In order to achieve the above-mentioned object, in the hydraulic shock absorber according to claim 1 of the present invention, the fixing bracket has a notch portion in a portion into which the lower end portion of the outer cylinder is press-fitted. And a mounting flange portion extending parallel to each other from both end edges of the cutout portion of the cylindrical portion, and narrowing the parallel interval between these flanges on the cylindrical portion side base end portions of both mounting flange portions. A rib is formed so as to extend in the direction, and the rib is formed above at least the center of the bolt insertion hole on the upper end side among the bolt insertion holes formed at a plurality of positions of both mounting flange portions.

Further, in the hydraulic shock absorber according to the present invention, the rib is formed above the center of the upper bolt insertion hole among the bolt insertion holes formed at the upper and lower portions of both mounting flange portions. It was configured.

Further, in the hydraulic shock absorber according to the present invention, the ribs are formed near the upper and lower end portions of both mounting flange portions, respectively.

Further, in the hydraulic shock absorber according to the present invention, the ribs are formed near the upper and lower end portions of both mounting flange portions and in the middle portion, respectively.

Further, in the hydraulic shock absorber according to a fifth aspect of the present invention, the inner peripheral surface of the rib contacting the outer cylinder is recessed outside the curved surface of the inner peripheral surface of the cylindrical portion in the vicinity of the joint with the inner peripheral surface of the cylindrical portion. A part is formed.

[0013]

The bolt fastening position with respect to the unsprung side of the fixing bracket becomes a position eccentric to the outside of the axial center portion of the hydraulic shock absorber, and the hydraulic shock absorber is mounted in a state of being inclined in the left-right direction of the vehicle. From that (see Figure 1),
When the vehicle is bouncing, a lateral bending moment acts on the lower end of the outer cylinder to which the fixing bracket is attached, and during the pressure stroke of the hydraulic shock absorber, the outer cylinder bites in particularly on the upper side of the fixing bracket. A force is applied to widen the distance between the two mounting flanges.At this time, the ribs formed above the center of the bolt insertion hole on the upper side receive the outer cylinder to secure the space between the two mounting flanges. The bite is blocked.

That is, since the rib serves as an inner bracket, the number of inner brackets is reduced, whereby the weight can be reduced and the number of parts can be reduced to reduce the cost.

Further, in the hydraulic shock absorber according to the present invention, the ribs are formed in the vicinity of the upper and lower end portions of both mounting flange portions, respectively, so that the bending rigidity and strength in the lateral direction of the vehicle are enhanced. be able to.

Further, in the hydraulic shock absorber according to the present invention, the ribs are formed in the vicinity of the upper and lower end portions of both mounting flange portions and in the middle portion, respectively. The strength can be further increased.

Further, in the hydraulic shock absorber according to a fifth aspect of the present invention, an escape recessed outside the curved surface of the inner peripheral surface of the cylindrical portion is formed in the vicinity of the connecting portion between the inner peripheral surface of the rib and the inner peripheral surface of the cylindrical portion, which contact the outer cylinder. By forming the part, even if there are variations in the dimensions of the outer cylinder and the fixing bracket, the ribs, which have the greatest effect on rigidity, strength, and durability, and the outer peripheral surface of the outer cylinder are in stable and reliable contact. This makes it possible to obtain sufficient strength and durability even with a lightweight and inexpensive one-piece fixing bracket.

[0018]

Embodiments of the present invention will now be described in detail with reference to the drawings. (First Embodiment) First, the construction of the hydraulic buffer of the first embodiment will be described.

FIG. 1 is a partially cutaway front view showing a state where a hydraulic shock absorber according to a first embodiment of the present invention is mounted on a vehicle. FIG. 2 is a view showing a fixing bracket portion as viewed from an arrow B in FIG. 1, and FIG. 1 is an enlarged cross-sectional plan view taken along the line AA of FIG. 1, in which 1 is an outer cylinder of a hydraulic shock absorber, 2 is a fixing bracket, 3 is a cylinder, 4 is a piston rod, 5 is a piston, 6 Is a rod guide, 7 is a base valve, and 8 is a spring seat.

The outer cylinder 1 is formed in a substantially cylindrical shape, and in particular, the outer circumference of the lower end portion on which the fixing bracket 2 is mounted is formed in a uniform circular shape. As shown in FIGS. 2 and 3, the fixing bracket 2 includes an outer cylinder 1
A cylindrical portion 21 having a partial cutout portion a along the circular outer peripheral surface of the lower end portion, and a pair of mounting flange portions 2 integrally extending in parallel from both end edges of the cutout portion a in the cylindrical portion 21.
The outer ribs 23 and 24 are integrally bent from the upper and lower end edges of the cylindrical portion 21 to the upper and lower end portions of the mounting flange portions 22 and 22, respectively.

Further, as shown in FIG. 1, both mounting flange portions 22 and 22 are provided with bolt insertion holes 25 and 2 at two upper and lower positions.
6 is formed. In addition, as shown in FIGS. 2 and 3, at the base end portions of both mounting flange portions 22 and 22 on the cylindrical portion 21 side, the cylindrical portion 21 is provided at the upper end portion and the lower end portion thereof along the circular outer peripheral surface of the outer cylinder 1. Ribs 27 extending in the direction of the cutout portion a,
28 is formed to project. Then, the rib 2 on the upper end side
7 is formed above the center of the bolt insertion hole 25, and as shown in FIG. 1, the rib 28 on the lower end side is formed below the center of the bolt insertion hole 26.

Then, the cylindrical portion 21 having a partial notch portion a
Is press-fitted onto the outer periphery of the outer cylinder 1 and the lower end of the cylindrical portion 21 and the outer cylinder 1 are fixed by welding b, whereby the fixing bracket 2 is fixedly attached to the outer cylinder 1.

Next, the operation of the embodiment will be described. The bolt fastening position (positions of the bolt insertion holes 25 and 26) of the fixing bracket 2 with respect to the unsprung side is eccentric to the outside of the axial center portion of the hydraulic shock absorber, and as shown in FIG. Since the container is attached in a state of being inclined in the left-right direction of the vehicle, a bending moment in the left-right direction acts on the lower end portion of the outer cylinder 1 to which the fixing bracket 2 is attached during bouncing of the vehicle, and
During the pressure stroke of the hydraulic shock absorber, particularly on the upper side of the fixing bracket 2, due to the biting of the outer cylinder 1, a force in the direction of widening the distance between the two mounting flange portions 22, 22 is received. , Both ribs 27, 2 on the upper end side
The outer cylinder 1 is received at 7 and the biting between the two mounting flange portions 22, 22 is prevented.

At the time of switching from the pressure stroke to the extension stroke of the hydraulic shock absorber, due to the repulsive force due to the release of the bending moment, contrary to the above, on the lower side of the fixing bracket 2, there is a slight outer cylinder. By the biting of 1, the mounting flange portions 22 and 22 receive a force in the direction of widening the distance between them, and at this time, the ribs 28 and 28 on the lower end portion also receive the outer cylinder 1 and both mounting flange portions are received. It is in a state in which the bite between the two 22 is prevented.

Therefore, it is possible to secure sufficient bending rigidity and strength in the vehicle left-right direction without providing an inner bracket.

As described above, in the hydraulic shock absorber of this embodiment, it is not necessary to form the recess in the outer cylinder 1, and the mounting brackets 22 and 22 of the fixing bracket 2 are provided. Since the ribs 27 and 28 can secure sufficient bending rigidity and strength in the vehicle left-right direction without providing an inner bracket,
Sufficient strength can be ensured even if the outer cylinder 1 and the fixing bracket 2 are made thin, which results in weight reduction and cost reduction by reducing the number of parts. ing.

Further, as described above, since the plate thickness of both the mounting flange portions 22, 22 of the fixing bracket 2 can be made thin, a stable fastening force can be obtained when the bolts and nuts are fastened to the unsprung side of the vehicle. It has the feature that it can be secured.

Further, the ribs 27 and 28 are provided with bolt insertion holes 2
By forming the upper and lower end portions of both mounting flange portions 22, 22 above and below the center of 5, 26, respectively, the bending rigidity and strength in the vehicle left-right direction can be further enhanced. are doing.

(Second Embodiment) Next, a second embodiment shown in FIG. 4 will be described. In the description of this embodiment, the same components as those in the first embodiment will be designated by the same reference numerals and the description thereof will be omitted, and only different points will be described.

In the hydraulic shock absorber of this embodiment, the rib 27 on the upper end side is located above the center of the upper bolt insertion hole 25,
The ribs 28 on the lower end side are formed at substantially the same positions as the centers of the lower bolt insertion holes 26, and the upper and lower ribs 2 are formed.
A rib 29 is also formed in the intermediate portion of 7, 28.

Therefore, this embodiment is characterized in that the bending rigidity and strength in the vehicle left-right direction can be further increased.

(Third Embodiment) Next, a third embodiment shown in FIGS. 5 to 7 will be described. In the description of this embodiment, the same components as those in the first embodiment will be designated by the same reference numerals and the description thereof will be omitted, and only different points will be described.

FIG. 5 is a partially cutaway front view showing a state in which the hydraulic shock absorber according to the third embodiment of the present invention is mounted on a vehicle, and FIG. 6 is a C view of FIG.
FIG. 7 is an enlarged cross-sectional plan view taken along line C, and FIG. 7 is an enlarged view of portion D in FIG. 6. As shown in detail in FIGS. 6 and 7, in the hydraulic shock absorber of this embodiment, the outer cylinder is A curved surface of the inner peripheral surface of the cylindrical portion 21 (outer diameter of the outer cylinder 1) in the vicinity of the connecting portion with the inner peripheral surface of the cylindrical portion 21 on the inner peripheral surface of the rib 27 (28) contacting with 1.
The relief portion 30 is formed so as to be recessed further outward by α.

That is, in this embodiment, even if the dimensions of the outer cylinder 1 and the fixing bracket 2 are varied, the relief action of the relief portion 30 has the greatest influence on the rigidity, strength, and durability of the rib 27 (28). ) And the outer peripheral surface of the outer cylinder 1 can be brought into stable and reliable contact with each other, whereby sufficient strength and durability can be obtained even with a lightweight and inexpensive one-piece fixing bracket 2. It has the feature of being able to

Although the embodiment of the present invention has been described in detail above with reference to the drawings, the specific structure is not limited to this embodiment, and even if there are design changes and the like within the scope not departing from the gist of the present invention. Included in the present invention.

For example, in the embodiment, the ribs 27, 28, 29 extending the cylindrical portion 21 in the direction of the cutout portion a are arranged along the circular outer peripheral surface of the outer cylinder 1, but slightly inside the circular outer peripheral surface of the outer cylinder 1. By extending in a direction that bites into, it becomes possible to increase the pressure input to the outer cylinder 1.

Further, in the embodiment, the case where the lower end portion of the outer cylinder 1 is formed in a uniform circular shape is shown. However, like the conventional example, a concave portion is formed on the outer peripheral surface of the outer cylinder 1, and the concave portion is formed. The ribs may be fitted and locked in this case, and in this case, the welding b can be omitted.

[0038]

As described above, in the hydraulic shock absorber of the present invention, the fixing bracket has a cylindrical portion having a notch in a portion into which the lower end of the outer cylinder is press-fitted, and a notch in the cylindrical portion. And a mounting flange portion extending parallel to each other from both end edges of the portion, and ribs extending in the direction of narrowing the parallel interval between these flanges are formed at the base end portions of the mounting flange portions on the cylindrical portion side. Since the ribs are formed at least above the center of the bolt insertion holes on the upper end side of the bolt insertion holes formed at multiple locations on both mounting flanges, the rigidity and strength against bending moment in the vehicle left-right direction It is possible to obtain the effect that the cost can be reduced by reducing the weight and the number of parts without lowering the cost.

Further, in the hydraulic shock absorber according to the present invention, the ribs are formed near the upper and lower end portions of both mounting flange portions, respectively, so that the bending rigidity and strength in the lateral direction of the vehicle can be improved. Can be increased.

Further, in the hydraulic shock absorber according to the present invention, the ribs are formed in the vicinity of the upper and lower end portions of both mounting flange portions and in the middle portion, respectively. -The strength can be further increased.

Further, in the hydraulic shock absorber according to the present invention, a relief recessed outside the curved surface of the inner peripheral surface of the cylindrical portion is formed in the vicinity of the connecting portion with the inner peripheral surface of the cylindrical portion on the inner peripheral surface of the rib that contacts the outer cylinder. By forming the part, even if there are variations in the dimensions of the outer cylinder and the fixing bracket, the ribs, which have the greatest effect on rigidity, strength, and durability, and the outer peripheral surface of the outer cylinder are in stable and reliable contact. This makes it possible to obtain sufficient strength and durability even with a lightweight and inexpensive one-piece fixing bracket.

[Brief description of drawings]

FIG. 1 is a front view showing a hydraulic shock absorber according to a first embodiment of the present invention in a vehicle mounted state.

FIG. 2 is a view as seen from an arrow B in FIG. 1 showing a fixing bracket portion of the hydraulic shock absorber of the first embodiment.

FIG. 3 is an enlarged cross-sectional plan view taken along the line AA of FIG. Is.

FIG. 4 is an enlarged front view of essential parts showing a fixing bracket portion of a hydraulic shock absorber according to a second embodiment of the present invention.

FIG. 5 is a front view showing a hydraulic shock absorber of a third embodiment of the present invention in a vehicle mounted state.

6 is an enlarged cross-sectional plan view taken along the line CC of FIG. Is.

FIG. 7 is an enlarged view of part D in FIG.

[Explanation of symbols]

 1 Outer cylinder 2 Fixing bracket 21 Cylindrical part 22 Mounting flange part 25 Bolt insertion hole 26 Bolt insertion hole 27 Rib 28 Rib 29 Rib 30 Relief part a Notch part

Claims (5)

[Claims] 1. The fixing bracket comprises a cylindrical portion having a notch in a portion into which the lower end of the outer cylinder is press-fitted, and a mounting flange portion extending parallel to each other from both end edges of the notch in the cylindrical portion. , Ribs that extend in the direction of narrowing the parallel spacing of these flanges are formed at the base end of the cylindrical side of both mounting flanges, and the ribs are one of the bolt insertion holes formed at multiple locations on both mounting flanges. A hydraulic shock absorber, which is formed at least above the center of the bolt insertion hole on the upper end side. 2. The liquid according to claim 1, wherein the rib is formed above a center of an upper bolt insertion hole of the bolt insertion holes formed at upper and lower portions of both mounting flange portions. Pressure shock absorber. 3. The hydraulic shock absorber according to claim 1, wherein the ribs are formed near both upper and lower end portions of both mounting flange portions. 4. The hydraulic shock absorber according to claim 1, wherein the ribs are formed near both upper and lower end portions of both mounting flange portions and in an intermediate portion, respectively. 5. A relief portion, which is recessed outward from a curved surface of the inner peripheral surface of the cylindrical portion, is formed in the vicinity of a connecting portion with the inner peripheral surface of the cylindrical portion on the inner peripheral surface of the rib that is in contact with the outer cylinder. 1-5
The hydraulic buffer according to any one of 1.