JPS6114676Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a piston rod protection cover for a hydraulic shock absorber, and is particularly advantageous for use in an inverted hydraulic shock absorber.

Conventionally, in hydraulic shock absorbers used around the wheels of automobiles, etc., in order to protect the piston rod from flying stones, mud, dust, etc., regardless of whether it is an upright type or an inverted type, it is equipped with a shock absorber as shown in Figure 1a. , has an inner diameter slightly larger than the outer diameter of cylinder A, and has one end fixed to the tip of piston rod B, so that even when shock absorber C is fully extended, its other open end is outside of cylinder A. A protective pipe D configured so as to overlap can be provided, or a bellows-type boot E that can be expanded and contracted as shown in FIG.
There is a structure in which the piston rod B is stretched between the tip of the piston rod B and the end of the cylinder A.
The former is much cheaper than the latter;
In the case of the latter boot E, a pipe-type protective cover is generally adopted because there is no fatigue deterioration caused by the weathering of the rubber or the repeated expansion and contraction bending loads associated with expansion and contraction movements.

Compared to a monocylindrical shock absorber that is filled with high-pressure gas to obtain damping force on the pressure side and is equipped with a free piston to separate gas and liquid, its basic length is shortened and its weight is reduced. The so-called inverted single-tube gas-filled hydraulic shock absorber, which eliminates the above-mentioned free piston, is advantageous in terms of damping force characteristics due to the reduction in unsprung weight. For this reason, it has attracted attention and become popular in recent years. However, especially in this type of inverted hydraulic shock absorber, when the above-mentioned protection pipe is adopted, there is a risk that mud, dust, etc. will gradually accumulate in the protection pipe.
To prevent this, a so-called drain opening must be provided at the bottom of the connection between the protective pipe and the piston rod (cover cap).

By the way, if the opening hole at the bottom of the protection pipe is too small, it will become clogged and the initial purpose will not be achieved, so it is necessary to make the opening size somewhat large, but the opening size is not too large. If this is the case, stones, etc. will easily fly into the protective pipe, which could damage the piston rod, and not only will the protective cover not be able to fulfill its original function, but it will also be difficult to install a simple opening hole. If you only paint the product, the paint will be sprayed into the protective pipe and adhere to the piston rod, resulting in the excess paint adhering to the piston rod damaging the oil seal and causing oil leaks. This will cause undesirable results.

Therefore, the present invention has been devised to provide a piston rod protection cover for a hydraulic shock absorber which can eliminate the above-mentioned drawbacks, and has an opening hole for a drain at the bottom of the cover cap body that is fixed to the piston rod, and an opening hole for the drain. When forming the barrier wall, for example, the opening hole is punched out from the cap body with a press or the like, and then cut and bent into a screen shape, or the part of the cap body in the opening hole is It is characterized in that it is provided by expansion molding by pressing or resin molding, and one end of the protective pipe is fixed to the cover cap main body. Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

Figures 2a and 2b show that the piston rod end is provided with a protective cover for the piston rod according to the present invention.
Piston rods with eyes are welded, and piston rods with stud bolts are welded.
A plan view showing an example of a cover cap body made of metal or resin, etc., which is fixed by welding or fastening, and FIG.
This is a longitudinal side view taken along line B ₁ - B ₁ , showing that the protective cover of the present invention has hole 1 for inserting the piston rod.
At the bottom of the cover cap body 1 having a
A drain opening hole 2 of an appropriate shape is punched out by pressing or resin molding, leaving a part of the cover cap body 1, and then cut upwards toward the outside of the cover cap body 1, thereby creating a screen. At the same time, one end of a protective pipe 4 having a predetermined length is formed on the outer periphery of the cover cap main body 1 by spot welding, or by other joining means (thermal deformation in the case of resin, elastic snap fastening, etc.). ), and the opening hole 2 prevents mud from accumulating inside the protective pipe 4. Furthermore, the presence of the barrier wall 3 not only effectively prevents flying stones and the like from accidentally jumping into the protective pipe 4 from the opening hole 2, but also prevents the outer periphery of the protective pipe 4 from being exposed when painting a product. This serves as a blocking wall against paint sprayed onto the piston rod 5 and the cylinder wall, thereby effectively preventing excess paint from entering the protective pipe 4 from the opening hole 2 and adhering to the piston rod 5. It is.

In addition, the above-mentioned barrier wall part is as shown in FIGS. 3a and 3b.
As shown at 3', it may be formed by cutting and raising the cover cap body 1 toward the inside, and it may also be formed by cutting and bending the cover cap body 1 inwardly, as shown at 3'', 3 in FIGS. 4a and 4b. In the case of a piston rod with an eye, for example, as shown in FIG. So as not to get in the way of rubber boots, etc.
The wall portion 3' is bent inward of the cover cap body 1, and the wall portions provided on both sides parallel to the axis of the eye 6 do not get in the way due to the drum shape on the outside of the eye 6. It is reasonable to form this as a partition wall 3 bent toward the outside of the cover cap body 1. Furthermore, the partition wall of the present invention is not only formed by cutting and raising it into the above-mentioned screen shape, but also by forming the cover cap body 1 around the opening hole 2' punched out by a press or the like, as illustrated in FIGS. '' can be left as it is as the wall part 7, or the sheared part by pressing etc. can be made into the open hole 2'', and at the same time, the vicinity of the sheared part can be shaped into an appropriate shape (in this example, a triangular pyramid shape). It is also possible to form a thin barrier wall part 8 by bulge molding, or in the case of a synthetic resin product, the barrier part may be integrally molded when molding the main body. A person skilled in the art can arbitrarily select and implement the barrier wall.

As mentioned above, the protective cover of the present invention has an opening hole for a drain and a wall portion for the opening hole simultaneously molded on the bottom of the cover cap body fixed to the piston rod in order to attach one end of the piston rod protection pipe. This prevents dirt from accumulating inside the protective cover, prevents the piston rod from colliding with flying stones, and ensures that the piston rod performs its initial function, and also eliminates excess paint when painting the product. It has the effect of reliably preventing adhesion to the piston rod, and there is no risk of impairing the sealing effect afterwards, and is more practical than conventional protective covers of this type, as well as being cost-effective. However, it has the advantage that it can be manufactured at a low cost because it can use what was previously wasted as a barrier as it is.

[Brief explanation of the drawing]

Figures 1a and b are longitudinal sectional views showing one embodiment of a conventional hydraulic shock absorber, and Figures 2a and b are plan views showing an embodiment of a cover cap body constituting the piston rod protection cover of the present invention. Same figure a
Figure ₃ a and b are plan views showing other embodiments of the cover cap body, and Figure 3 a is a longitudinal side view taken along line _{B 1} - B ₁ . A vertical side view, FIGS. 4a and 4b are a plan view showing still another embodiment of the cover cap body, and FIG.
A longitudinal side view taken along the line B ₃ - _{B 3} , Fig. 5 is an enlarged longitudinal side view showing yet another embodiment of the cover cap body, and Figs. 6 a and b show other embodiments of the cover cap main body. FIG. 2 is a plan view and a vertical side view showing an example. 1, 1'...Cover cap body, 2, 2',
2″……opening hole, 3, 3′, 3″, 3, 7, 8…
...Bullet part, 4...Protection pipe, 5...Piston rod.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) An opening hole for a drain and a barrier for the opening hole are simultaneously molded on the bottom of the cover cap body fixed to the tip of the piston rod of the hydraulic shock absorber, and the cover cap A piston rod protection cover for a hydraulic shock absorber, characterized in that one end of a protective pipe of an appropriate length having an inner diameter slightly larger than the outer diameter of the shock absorber cylinder is attached to the main body. (2) A piston rod protection cover for a hydraulic shock absorber according to claim 1, wherein the barrier wall for the drain opening is a cut-and-raised bent piece. (3) A piston rod protection cover for a hydraulic shock absorber according to claim 1, wherein the barrier wall for the drain opening is a pressed or molded bulging piece having an appropriately shaped shape. (4) The piston rod protection cover for a hydraulic shock absorber according to claim 1, wherein the barrier wall for the drain opening is located particularly on the radially outer side of the opening.