Rebound stopper

The present invention relates to a rebound stopper.

Conventionally, a rebound stopper is provided on an automobile suspension or the like in order to absorb an impact when the vehicle body floats in the air. As such a rebound stopper, a urethane-made substantially cylindrical one is known (see Patent Documents 1 and 2). A rebound stopper according to such a conventional example will be described with reference to FIG. 7. FIG. 7 is a schematic cross-sectional view showing a mounted state of the rebound stopper according to the conventional example.

The rebound stopper 500 is arranged so that one end 501 thereof comes into contact with the rebound sheet 210 provided on the rod 200, and when the rod 200 extends beyond a certain level, the other end 502 is provided on the inner circumference of the cylinder 300. It is configured to collide with the rod guide 310. Then, when the other end side 502 collides with the rod guide 310, the rebound stopper 500 is sandwiched and compressed by the rebound sheet 210 and the rod guide 310 to absorb the impact.

However, the urethane rebound stopper 500 has a relatively high hardness, and the initial compression amount (deflection amount) at the time of collision is small, so that there is a problem that the collision sound becomes loud.

<p><patcit num="1"><text>Japanese Unexamined Patent Publication No. 2004-225744</text></patcit><patcit num="2"><text>JP-A-2002-39252</text></patcit></p>

<p> An object of the present invention is to provide a rebound stopper for reducing collision noise.</p>

<p> The present invention employs the following means to solve the above problems.</p><p> That is, the rebound stopper of the present invention is It is mounted on the outer circumference of a rod that can be reciprocated in the cylinder, and one end side faces the rebound seat provided on the rod, and the other end side is attached to a collided member provided on the inner circumference of the cylinder. Arranged to face each other When the rod moves in the direction of the rebound sheet toward the collided member, the other end side collides with the collided member and is compressed by the rebound sheet and the collided member to absorb the impact. , In a substantially cylindrical urethane rebound stopper It is characterized in that a plurality of protrusions are provided on both end sides, and the protrusions on one end side and the protrusions on the other end side are arranged at positions shifted in the circumferential direction.</p><p> According to the present invention, on the opposite side of each protrusion on one end side, there is a space portion formed between the protrusions provided on the other end side. Similarly, on the opposite side of each protrusion on the other end side, there is a space portion formed between the protrusions provided on one end side. This rebounds When the stopper is compressed by the rebound sheet and the collided member, the opposite side of each protrusion can be deformed so as to escape to the space, so that the amount of compression (deflection) of the initial rebound stopper at the time of collision can be increased. It can reduce the collision noise.</p><p> One end side is provided with a total of three protrusions every 120 ° in the circumferential direction, and the other end side is also provided with a total of three protrusions every 120 ° in the circumferential direction. It is preferable that the protrusions are arranged at a position shifted by 60 ° in the circumferential direction with respect to the arrangement position of the protrusions on one end side.</p><p> As a result, it is possible to secure a large distance between the protrusions while increasing the concentricity of the rebound stopper with respect to the rod. Therefore, the above-mentioned space can be increased, and the amount of compression (deflection) of the rebound stopper can be increased.</p>

<p> As described above, according to the present invention, the impact sound can be reduced.</p>

<figref num="1">FIG. 1 is a perspective view of a rebound stopper according to an embodiment of the present invention.</figref><figref num="2">FIG. 2 is a plan view of the rebound stopper according to the embodiment of the present invention.</figref><figref num="3">FIG. 3 is a schematic cross-sectional view (AA cross-sectional view of FIG. 2) of the rebound stopper according to the embodiment of the present invention.</figref><figref num="4">FIG. 4 is a schematic cross-sectional view showing a mounted state of the rebound stopper according to the embodiment of the present invention.</figref><figref num="5">FIG. 5 is a table showing the test results when the dimensions and the like of each part of the rebound stopper according to the embodiment of the present invention are changed.</figref><figref num="6">FIG. 6 is a graph showing the relationship between the amount of deflection and the load in the rebound stopper according to the embodiment of the present invention.</figref><figref num="7">FIG. 7 is a schematic cross-sectional view showing a mounted state of the rebound stopper according to the conventional example.</figref>

Hereinafter, embodiments for carrying out the present invention will be described in detail exemplarily based on examples with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described in this embodiment are not intended to limit the scope of the present invention to those, unless otherwise specified. ..

(Example) The rebound stopper according to the embodiment of the present invention will be described with reference to FIGS. 1 to 6.

&lt;Structure of rebound stopper&gt; In particular, the configuration of the rebound stopper according to the embodiment of the present invention will be described with reference to FIGS. 1 to 4.

The rebound stopper 100 according to this embodiment is used for a suspension of an automobile or the like. That is, as shown in FIG. 4, the rebound stopper 100 is mounted on the outer circumference of a rod (piston rod) 200 provided so as to be reciprocating in the cylinder 300 constituting the suspension. Further, the rebound stopper 100 is arranged so that one end side thereof faces the rebound seat 210 provided on the rod 200 and the other end side faces the rod guide 310 as a collided member provided on the inner circumference of the cylinder 300. Will be done. The rod guide 310 functions as a bearing for the rod 200.

In the normal state, one end side of the rebound stopper 100 is in contact with the rebound sheet 210, and there is a gap between the other end side and the rod guide 310. Then, when the vehicle body floats in the air, the rod 200 moves upward in FIG. That is, the rod 200 moves in the direction in which the rebound seat 210 faces the rod guide 310. Then, when the movement amount of the rod 200 exceeds a certain value, the other end side of the rebound stopper 100 collides with the rod guide 310. As a result, the rebound stopper 100 is compressed by the rebound seat 210 and the rod guide 310 to absorb the impact.

As the material of the rebound stopper 100, urethane, which is a material having relatively high rigidity and excellent durability, is used. Further, the rebound stopper 100 is composed of a substantially cylindrical member, and the rod 200 is inserted into the cylinder. A plurality of annular grooves 110 are formed on the outer peripheral surface of the rebound stopper 100 so that the overall shape is a bellows shape. As a result, it is easier to be compressed as compared with the case where the plurality of annular grooves 110 are not formed.

The rebound stopper 100 according to this embodiment is provided with a plurality of protrusions (three locations in this embodiment) on both end sides thereof. For convenience of explanation, the plurality of protrusions provided on one end side are referred to as a first protrusion 121, a second protrusion 122, and a third protrusion 123, respectively, and a plurality of protrusions provided on the other end side. Are referred to as a fourth protrusion 131, a fifth protrusion 132, and a sixth protrusion 133, respectively.

The first protrusion 121, the second protrusion 122, and the third protrusion 123 are provided at intervals of 120 ° in the circumferential direction. Similarly, the fourth protrusion 131, the fifth protrusion 132, and the sixth protrusion 133 are also provided at intervals of 120 ° in the circumferential direction. The fourth protrusion 131, the fifth protrusion 132, and the sixth protrusion 133 are 60 ° in the circumferential direction with respect to the arrangement positions of the first protrusion 121, the second protrusion 122, and the third protrusion 123. It is placed in a staggered position.

Since a plurality of protrusions are provided in this way, in a normal state, the first protrusion 121, the second protrusion 122, and the third protrusion 123 are on the rebound sheet 210 on one end side of the rebound stopper 100. It is in contact. At this time, between the first protrusion 121 and the second protrusion 122, between the second protrusion 122 and the third protrusion 123, and between the third protrusion 123 and the first protrusion 121. Each space is formed. Then, when the other end side of the rebound stopper 100 collides with the rod guide 310, the fourth protrusion 131, the fifth protrusion 132, and the sixth protrusion 133 become the rod guide 310 on the other end side of the rebound stopper 100. It will be in a state of contact. At this time, between the 4th protrusion 131 and the 5th protrusion 132, between the 5th protrusion 132 and the 6th protrusion 133, and between the 6th protrusion 133 and the 4th protrusion 131, Spaces are formed in each.

&lt;Advantages of the rebound stopper according to this embodiment&gt; As described above, according to the rebound stopper 100 according to the present embodiment, on the opposite side of each protrusion (first protrusion 121, second protrusion 122, third protrusion 123) on one end side, the other There are space portions formed between the protrusions (4th protrusion 131, 5th protrusion 132, 6th protrusion 133) provided on the end side, respectively. Similarly, on the opposite side of each protrusion on the other end side, there is a space portion formed between the protrusions provided on one end side.

As a result, when the rebound stopper 100 is compressed by the rebound seat 210 and the rod guide 310, the opposite side of each protrusion can be deformed so as to escape to the space. Therefore, the amount of compression (deflection) of the initial rebound stopper 100 at the time of collision can be increased, and the collision noise can be reduced.

Further, in this embodiment, protrusions (first protrusion 121, second protrusion 122, third protrusion 123) are provided on one end side of the rebound stopper 100 at every 120 ° in the circumferential direction. In addition, protrusions (4th protrusion 131, 5th protrusion 132, 6th protrusion 133) are provided at a total of 3 locations on the other end side at 120 ° intervals in the circumferential direction, and the protrusion on the other end side is one end. A configuration is adopted in which the protrusions on the side are arranged at a position shifted by 60 ° in the circumferential direction with respect to the arrangement position.

As a result, it is possible to secure a large distance between the protrusions while increasing the concentricity of the rebound stopper 100 with respect to the rod 200. Therefore, the above-mentioned space can be increased, and the amount of compression (deflection) of the rebound stopper 100 can be increased.

It is possible to provide four or more protrusions on each end of the rebound stopper 100, but in this case, the distance between the protrusions becomes shorter and the amount of compression of the rebound stopper 100 becomes smaller. .. Further, it is possible to increase the distance between the protrusions by providing two protrusions at both ends of the rebound stopper 100, but in this case, the concentricity of the rebound stopper 100 with respect to the rod 200 becomes low. Will end up. However, depending on the usage environment, the protrusions provided at both ends of the rebound stopper 100 do not have to be three at a time. It is not necessary to make the number of protrusions provided at both ends the same, and for example, one end side may be set to three places and the other end side may be set to two places. However, it is necessary to arrange the protrusion on one end side and the protrusion on the other end side at positions shifted in the circumferential direction.

&lt;Others&gt; As described above, a plurality of protrusions are provided at both ends of the rebound stopper 100, and the protrusions on one end side and the protrusions on the other end side are arranged at positions shifted in the circumferential direction to cause a collision. The amount of compression (deflection) of the initial rebound stopper 100 at the time can be increased, and the collision noise can be reduced.

However, in order to make it easier to deform, the height of the protrusion relative to the total height of the rebound stopper 100 (the distance from the tip of the protrusion on one end side to the tip of the protrusion on the other end side) may be too high, or the rebound stopper 100 may be made too high. If the compression ratio of the above is increased too much, the tip of the protrusion is likely to be chipped. Therefore, a test was conducted to inspect how much the height of the protrusion with respect to the total height of the rebound stopper 100 could be increased and how much the compression ratio could be increased. That is, in the configuration of the rebound stopper 100 shown in the above embodiment, the total height and the height of the protrusions were variously changed, and the amount of deflection under a durable load was also changed variously, and the durability was inspected.

Fig. 5 shows the "deflection amount under endurance load", "projection height (projection height)", "total height", "projection height relative to total height", and "compression rate" for various samples. It is a table listing the test results for "durability". Regarding "durability", "OK" was given to those having no defects at the tips of the protrusions, and "NG" was given to those having defects. Further, FIG. 6 is a graph showing the relationship between the deflection and the load of the sample 10 (NG product) and the sample 11 (OK product) among the samples shown in FIG. In the graph, the solid line is the graph of sample 11 and the dotted line is the graph of sample 10.

From the above test results, it was found that it is desirable to set the height of the protrusion to 9% or less of the total height of the rebound stopper 100, and to set the compression ratio to 24% or less under a durable load.

100 rebound stopper 110 annular groove 121 1st protrusion 122 2nd protrusion 123 3rd protrusion 131 4th protrusion 132 5th protrusion 133 6th protrusion 200 rod 210 rebound seat 300 cylinder 310 rod guide