JP4695295B2 - Hydraulic shock absorber knuckle bracket structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a knuckle bracket structure for a hydraulic shock absorber.
[0002]
[Prior art]
(1) As a knuckle bracket structure of a hydraulic shock absorber, Japanese Patent Laid-Open No. 2000-18309 describes a main body portion (bracket main body) for embedding a tube of a hydraulic shock absorber and a pair of knuckle mounting portions projecting in parallel in the horizontal direction from the main body portion. (Holding part) and a mounting hole provided symmetrically in the knuckle mounting part, and the lower part of the tube is held by the main body part, and the folded part provided on the upper and lower peripheral edges a of the main body part and the upper part of the knuckle mounting part The inner periphery b of the (upper support piece) is fixed to the outer surface of the tube by welding.
[0003]
However, the distance between the vehicle body side mounting portion of the hydraulic shock absorber (vehicle body side mounting portion fixed to the upper end portion of the piston rod) and the tube mounting portion of the knuckle bracket (the upper end peripheral edge a of the main body portion and the inner periphery b of the folded portion) is Long and the bending moment based on the bending input from the knuckle is large. For this reason, bending stress concentrates on the tube, and it is necessary to increase the strength of the tube. The thickness of the tube increases and becomes heavy, and the weight cannot be reduced.
[0004]
(2) As another knuckle bracket structure of the hydraulic shock absorber, practical 2594425 has an annular member attached to the outer periphery of the tube in the welded portion which is the upper peripheral edge of the knuckle bracket (mounting bracket), and the welded portion is attached to the annular member. The one to be welded is disclosed. At the peripheral edge of the upper end of the knuckle bracket, the bending stress acting location is dispersed in the circumferential direction to prevent multi-axial stress concentration due to bending input.
[0005]
However, the knuckle bracket and the other annular member are used, which increases the number of parts and increases the cost.
[0006]
An object of the present invention is to reinforce a stress concentration portion caused by bending input without increasing the number of parts, and to reduce the weight of a knuckle bracket and a tube made of a single plate.
[0007]
[Means for Solving the Problems]
According to the first aspect of the present invention, there is provided a C-shaped main body portion provided along the tube of the hydraulic shock absorber and holding the tube in the axial direction and the circumferential direction, and protruding from both ends of the C-shaped cross section of the main body portion. a knuckle mounting portion of the left and right extending parallel, have a from the upper end of the left and right knuckle mounting portion and the right and left folded portions folded inward, the hydraulic shock absorber of the knuckle fixing the knuckle bracket comprising a single plate at the bottom of the tube In the bracket structure, the main body part and the left and right folded parts extend upward from the upper ends of the left and right knuckle attachment parts to form an integrated support part, and the main body part integrated to form the support part, and the main body part The upper and lower peripheral edges of the left and right folded parts are welded to the outer periphery of the tube, and the left and right folded parts that constitute the support part are the portions from the left and right knuckle attachment parts to the upper end part of the tube. And a box-shaped floated al is obtained by welding only the upper peripheral portion is brought into contact with the outer circumference of the tube.
[0009]
[Action]
(a) The main body portion and the folded portion are extended upward from the upper end of the knuckle attachment portion to form an integrated support portion. Thereby, without increasing the number of parts, the stress concentration portion caused by bending input can be reinforced, and the weight of the knuckle bracket and the tube made of a single plate can be reduced.
[0010]
(b) The folded portion that constitutes the support portion has a box shape in which the portion from the knuckle mounting portion side to the upper end portion does not contact the tube, and only the upper end portion contacts the tube. Thereby, the stress concentration which generate | occur | produces in the folding | returning part of a knuckle bracket can be eased, and the weight reduction of a knuckle bracket can be achieved.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
1 is a cross-sectional view of the hydraulic shock absorber, FIG. 2 is a side view of the knuckle bracket of FIG. 1, FIG. 3 is a front view of the knuckle bracket of FIG. 1, and FIG. FIG. 5 is a bottom view, FIG. 5 shows a lower spring seat, (A) is a plan view, (B) is a cross-sectional view along the line BB, and (C) is a cross-sectional view along the line CC.
[0012]
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 damper tube 11 (outer tube), and the lower end of the damper tube 11 is inserted. It is connected to the axle via a knuckle bracket 13 fixed by welding, and connected to the vehicle body via a vehicle body side mounting bracket (not shown) to a piston rod 12 protruding from the damper tube 11. The bottom portion of the damper tube 11 is subjected to spinning processing, and a stabilizer bracket 15 is fixed to the intermediate outer peripheral portion of the damper tube 11 by welding.
[0013]
In the vehicle body side mounting bracket, an upper bearing plate 17 is fixed by a nut 16 fastened to an upper end portion of the piston rod 12, and a bearing 18 and a lower bearing plate 19 are loaded on the lower surface of the upper bearing plate 17. Then, the upper spring seat 21 is supported on the lower bearing plate 19 via the spacer 20, the lower spring seat 22 is fixed to the outer periphery of the damper tube 11, and the suspension spring 23 is interposed between the upper spring seat 21 and the lower spring seat 22. Is intervening. The upper spring seat 21 is provided with a spring seat cover 24. The spring seat cover 24 is made of resin, and is provided with spring drop-off prevention mechanisms at a plurality of locations.
[0014]
The hydraulic shock absorber 10 holds the bump rubber 25 at the center of the upper spring seat 21 and fixes the bump stopper cap 26 at the upper end of the damper tube 11. When the hydraulic shock absorber 10 is most compressed, the bump rubber 25 abuts against the bump stopper cap 26 to restrict the most compressed stroke.
[0015]
Therefore, in the hydraulic shock absorber 10, a piston valve device in which the impact force received by the vehicle from the road surface is absorbed by the elastic force of the suspension spring 23, and the expansion and contraction vibration of the suspension spring 23 is provided in a piston (not shown). Vibration is suppressed by the damping action of a base valve device provided in the cylinder.
[0016]
However, the knuckle bracket 13 is formed by bending a single plate as shown in FIGS. 1 to 4, and includes a main body portion 31, a knuckle attachment portion 32, a folding portion 33, and a support portion 34. The main body 31 has a C-shaped cross section, is provided along the axial direction and the circumferential direction of the damper tube 11, and holds the outer periphery of the damper tube 11. The knuckle attachment portion 32 is formed of a pair of left and right protrusions that continuously protrude from both ends of the C-shaped cross section of the main body portion 31 and extend in parallel to each other, and includes upper and lower attachment holes 32A and 32B. The body portion 31 and the left and right knuckle attachment portions 32, 32 include an outward reinforcing flange 35 that extends from the center of the front end of the knuckle attachment portion 32 through the lower end of the knuckle attachment portion 32 to the lower half of the lower end of the body portion 31. 36 is formed. Reinforcing ribs 37 are formed at the bent boundary portions of the main body portion 31 and the left and right knuckle attachment portions 32, 32 so that the bent boundary portions are expanded outward. The folded portion 33 is formed to be bent inward from the upper ends of both knuckle attachment portions 32, 32. The main body 31 and the folded portion 33 are integrated by extending upward from the upper end of the knuckle attachment portion 32, and the upper extension (L) is used as the support portion 34. The knuckle bracket 13 is welded to the bottom of the damper tube 11 at the lower end periphery of the main body 31 at the welded portion a (FIG. 4), and the upper end periphery of the support portion 34 is welded to the outer periphery of the damper tube 11 at the welded portion b. (FIGS. 2 and 3).
[0017]
The folded portion 33 constituting the support portion 34 has a box shape that does not contact the damper tube 11 from the knuckle mounting portion 32 side to the upper end portion, and only the upper end portion contacts the damper tube 11 at the welded portion b. It was supposed to be
[0018]
It is preferable that the holding range of the damper tube 11 along the circumferential direction of the damper tube 11 of the main body 31 extends over a range of half or more of the damper tube 11. A brake hose bracket 27 is fixed to the main body 31 by welding.
[0019]
Therefore, according to this embodiment, there are the following operations.
(1) The main body 31 and the folded portion 33 are extended upward from the upper end of the knuckle attachment portion 32 to form an integrated support portion 34. Thereby, the stress concentration part resulting from a bending input can be reinforced and the weight reduction of the knuckle bracket 13 and the damper tube 11 which consist of a single board can be achieved, without increasing a number of parts.
[0020]
(2) At the joint portion between the knuckle bracket 13 and the damper tube 11 on which bending stress acts, the main body portion 31 constituting the support portion 34 extends upward from the upper end of the knuckle mounting portion 32 and widely holds the damper tube 11. Thus, the bending stress acting portions are dispersed in the axial direction of the damper tube 11 to prevent stress concentration, and the damper tube 11 is reinforced. For this reason, the plate | board thickness of the damper tube 11 can be made small and it can reduce in weight.
[0021]
(3) Since the support portion 34 (tube mounting portion) of the knuckle bracket 13 is extended upward, the distance L from the vehicle body side mounting portion is shortened, and the bending moment M (= F × L) based on the bending input F from the knuckle Can be reduced. For this reason, the bending stress which acts on the damper tube 11 is reduced, and the plate thickness of the damper tube 11 can be reduced to reduce the weight.
[0022]
(4) The folded portion 33 constituting the support portion 34 has a box shape in which the portion from the knuckle attachment portion 32 side to the upper end portion does not contact the damper tube 11, and only the upper end portion contacts the damper tube 11. Thereby, the stress concentration which generate | occur | produces in the folding | returning part 33 of the knuckle bracket 13 can be eased, and the weight reduction of the knuckle bracket 13 can be achieved.
[0023]
(5) Since the folded portion 33 is box-shaped and the root portion connected to the knuckle mounting portion 32 of the folded portion 33 is lifted from the damper tube 11 and gently spreads, the stress acting on the folded portion 33 can be dispersed. The thickness of the knuckle bracket 13 can be reduced to reduce the weight. When the folded portion 33 is brought into close contact with the damper tube 11 from the root portion, the stress acting on the folded portion 33 is concentrated on the root portion.
[0024]
The hydraulic shock absorber 10 includes a dust cover 40 continuous with the bump rubber 25 described above (FIG. 1). The dust cover 40 includes a bellows portion 41 connected to the lower end portion of the bump rubber 25 and an engaging portion 42 connected to the lower end portion of the bellows portion 41. The engaging portion 42 includes an inner circumferential groove portion that engages with an outwardly projecting annular flange portion 26 </ b> A provided at the lower portion of the bump stopper cap 26. The dust cover 40 includes an annular tapered introduction portion 43 at the lower portion of the end portion of the engaging portion 42, and tensile pieces 44 at a plurality of positions in the circumferential direction below the tapered introduction portion 43, and the tensile pieces 44 are pulled with fingers. Thus, the tapered introduction portion 43 is slid around the flange portion 26A to smoothly engage the inner peripheral groove portion of the engagement portion 42 with the flange portion 26A.
[0025]
Further, the hydraulic shock absorber 10 includes the above-described lower spring seat 22 as follows (FIG. 5). The lower spring seat 22 extends a support groove 51 for constraining the end portion of the suspension spring 23 in the circumferential direction, and the remaining portion in the circumferential direction corresponding to the rising portion of the suspension spring 23 is a plane portion 52. The end stopper 51A with respect to the end of the end winding portion of the suspension spring 23 is rounded up to a stopper shape, and the back side of the end stopper 51A is formed in a hollow shape. The lower spring seat 22 is formed by integrally forming a flange portion 53 that prevents the suspension spring 23 from falling off at the edge of the outer periphery. The flange portion 53 has a plurality of elongated holes 54 for weight reduction and dust / drainage, A hole 55 for positioning the spring seat 22 is provided.
[0026]
Although the embodiment of the present invention has been described in detail with reference to the drawings, 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.
[0027]
【The invention's effect】
As described above, according to the present invention, it is possible to reinforce the stress concentration portion caused by bending input without increasing the number of parts, and to reduce the weight of the knuckle bracket and the tube made of a single plate.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a hydraulic shock absorber.
FIG. 2 is a side view showing the knuckle bracket of FIG. 1;
FIG. 3 is a front view showing the knuckle bracket of FIG. 1;
4 is a bottom view showing the knuckle bracket and the lower spring seat of FIG. 1. FIG.
5A and 5B show a lower spring seat, in which FIG. 5A is a plan view, FIG. 5B is a cross-sectional view taken along line BB, and FIG. 5C is a cross-sectional view taken along line CC.
[Explanation of symbols]
10 Hydraulic shock absorber 11 Damper tube (tube)
13 knuckle bracket 31 main body 32 knuckle mounting portion 33 folded portion 34 support portion

Claims (1)

A main body portion having a C-shaped cross section that is provided along the tube of the hydraulic shock absorber and holds the tube in the axial direction and the circumferential direction, and left and right knuckle attachments protruding from both ends of the C-shaped cross section of the main body portion and extending in parallel to each other And a knuckle bracket structure for a hydraulic shock absorber having left and right folded portions bent inward from the upper ends of the left and right knuckle attachment portions, and a knuckle bracket made of a single plate fixed to the lower portion of the tube.
The main body part and the left and right folded parts extend upward from the upper ends of the left and right knuckle attachment parts to form an integrated support part, and the main body part integrated to form the support part, and the left and right folded parts of the main body part Each upper peripheral edge of the part is welded to the outer periphery of the tube,
The left and right folded parts that make up the support part have a box shape in which the part from the left and right knuckle attachment parts side to the upper end part is floated from the tube, and only the upper peripheral edge part is in contact with the outer periphery of the tube and welded. Features a knuckle bracket structure of a hydraulic shock absorber.

Images