Shock-absorbing stopper

Abstract

Shock-absorbing stopper for preventing an elastic body from contacting a mating component, to cause sliding wear in a structure having a hollow in an outer peripheral surface. The stopper has a cylindrical elastic body, to which a fixed-side metal fitting is connected and to which a movable-side metal fitting is connected and an annular hollow in the outer peripheral surface, in which the stopper is sectioned into three portions by the hollow of a small diameter portion formed by the hollow, a fixed-side large diameter portion located closer to the fixed side, and a movable-side large diameter portion located closer to the movable side. The outer diameter dimension of the movable-side large diameter portion is smaller than the outer diameter dimension of the fixed-side large diameter portion and the axial width of the movable-side large diameter portion is smaller than the axial width of the fixed-side large diameter portion.

Claims

1. A shock-absorbing stopper comprising: a cylindrical elastic body, to one end portion of which a fixed-side metal fitting is connected and to another end portion of which a movable-side metal fitting is connected and which has an annular hollow in an outer peripheral surface of the cylindrical elastic body, wherein the cylindrical elastic body is sectioned into three portions by the hollow of a small diameter portion formed by the hollow, a fixed-side large diameter portion located closer to a fixed side relative to the hollow, and a movable-side large diameter portion located closer to a movable side relative to the hollow, an outer diameter dimension of the movable-side large diameter portion is set smaller than an outer diameter dimension of the fixed-side large diameter portion, an axial width of the movable-side large diameter portion is set smaller than an axial width of the fixed-side large diameter portion, a portion of the fixed-side large diameter portion overlaps with the fixed-side metal fitting in a radial direction of the shock-absorbing stopper and is disposed radially outward from a radially outer surface of the fixed-side metal fitting, the fixed-side metal fitting includes a through hole, the movable-side metal fitting includes a through hole, and a surface of the cylindrical elastic body is disposed inside the through hole of only one of the fixed-side metal fitting and the movable-side metal fitting and is abutted against a radially inner surface of the one of the fixed-side metal fitting and the movable-side metal fitting in the radial direction of the shock-absorbing stopper.

2. The shock-absorbing stopper according to claim 1, wherein the fixed-side metal fitting is plate-shaped and includes an annular ring shape with the through hole.

3. The shock-absorbing stopper according to claim 1, wherein the movable-side metal fitting is plate-shaped and includes an annular ring shape with the through hole.

4. The shock-absorbing stopper according to claim 1, wherein the fixed-side metal fitting is plate-shaped and includes an annular ring shape with the through hole, the movable-side metal fitting is plate-shaped and includes an annular ring shape with the through hole, and an inner end of the fixed-side metal fitting projects radially inwardly relative to an inner end of the movable-side metal fitting so that the inner end of the fixed-side metal fitting does not overlap with the movable-side metal fitting in an axial direction of the shock-absorbing stopper.

5. The shock-absorbing stopper according to claim 1, wherein the movable-side metal fitting is L-shaped in cross section and includes an annular ring shape with the through hole.

6. The shock-absorbing stopper according to claim 1, wherein the fixed-side metal fitting is rectangular-shaped in cross section and includes an annular ring shape with the through hole, the movable-side metal fitting is L-shaped in cross section and includes an annular ring shape with the through hole, and an inner end of the movable-side metal fitting projects radially inwardly relative to an inner end of the fixed-side metal fitting so that the inner end of the movable-side metal fitting does not overlap with the fixed-side metal fitting in an axial direction of the shock-absorbing stopper.

7. The shock-absorbing stopper according to claim 1, wherein a portion of the cylindrical elastic body does not overlap with the fixed-side metal fitting and the movable-side metal fitting in an axial direction of the shock-absorbing stopper.

8. The shock-absorbing stopper according to claim 1, wherein a portion of the movable-side large diameter portion overlaps with the movable-side metal fitting in the radial direction of the shock-absorbing stopper and is disposed radially outward from a radially outer surface of the movable-side metal fitting.

9. A shock-absorbing stopper assembly, comprising: a shock-absorbing stopper including: a cylindrical elastic body, to one end portion of which a fixed-side metal fitting is connected and to another end portion of which a movable-side metal fitting is connected and which has an annular hollow in an outer peripheral surface of the cylindrical elastic body; and a housing that includes an inner peripheral surface surrounding the shock-absorbing stopper in a circumferential direction, wherein the cylindrical elastic body is sectioned into three portions by the hollow of a small diameter portion formed by the hollow, a fixed-side large diameter portion located closer to a fixed side relative to the hollow, and a movable-side large diameter portion located closer to a movable side relative to the hollow, an outer diameter dimension of the movable-side large diameter portion is set smaller than an outer diameter dimension of the fixed-side large diameter portion, an axial width of the movable-side large diameter portion is set smaller than an axial width of the fixed-side large diameter portion, a portion of the fixed-side large diameter portion overlaps with the fixed-side metal fitting in a radial direction of the shock-absorbing stopper and is disposed radially outward from a radially outer surface of the fixed-side metal fitting, the fixed-side metal fitting includes a through hole, the movable-side metal fitting includes a through hole, and a surface of the cylindrical elastic body is disposed inside the through hole of only one of the fixed-side metal fitting and the movable-side metal fitting and is abutted against a radially inner surface of the one of the fixed-side metal fitting and the movable-side metal fitting in the radial direction of the shock-absorbing stopper.

10. The shock-absorbing stopper assembly according to claim 9, wherein when the shock-absorbing stopper is compressed, the cylindrical elastic body does not exert a pressing force against the inner peripheral surface of the housing.

11. The shock-absorbing stopper assembly according to claim 9, wherein a radial gap is maintained between the shock-absorbing stopper and the inner peripheral surface of the housing across an entire axial length of the shock-absorbing stopper.

12. The shock-absorbing stopper assembly according to claim 9, wherein a portion of the movable-side large diameter portion overlaps with the movable-side metal fitting in the radial direction of the shock-absorbing stopper and is disposed radially outward from a radially outer surface of the movable-side metal fitting.

Description

BRIEF EXPLANATION OF THE DRAWINGS

(1) FIG. 1 is a cross-sectional view of a principal portion of a shock-absorbing stopper according to a first embodiment of the present invention.

(2) FIG. 2 is a cross-sectional view of a principal portion of a shock-absorbing stopper according to a second embodiment of the present invention.

(3) FIGS. 3A and 3B are FIG. 3 is a cross-sectional view views of a principal portion of a shock-absorbing stopper according to a conventional example.

(4) FIG. 4 is a cross-sectional view of a principal portion of a shock-absorbing stopper according to a reference example.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(5) Next, embodiments of the present invention are described with reference to the drawings.

First Embodiment

(6) As illustrated in FIG. 1, a shock-absorbing stopper 11 according to this embodiment has a cylindrical elastic body 12 containing a predetermined rubber-like elastic body, in which an annular fixed-side metal fitting 13 is connected to one axial end portion (upper end portion in the figure) of the cylindrical elastic body 12 and an annular movable-side metal fitting 14 is connected to the other axial end portion (lower end portion in the figure) thereof. The one end portion (hereinafter sometimes also referred to as a fixed-side end portion 15) to which the fixed-side metal fitting 13 is connected is fixed to the housing 61 which is a mating component. A shaft (not illustrated) which is an actuating component collides with the other end portion (hereinafter sometimes also referred to as a movable-side end portion 16) to which the movable-side metal fitting 14 is connected, so that the other end portion is displaced together with the shaft.

(7) An annular hollow 17 is provided in the outer peripheral surface of the elastic body 12. Moreover, due to the fact that the annular hollow 17 is provided in the outer peripheral surface of the elastic body 12 as described above, the shock-absorbing stopper 11 is sectioned into three portions, that is, a small diameter portion 11A formed by the hollow 17, and having an outer peripheral surface of a relatively small diameter, a fixed-side large diameter portion 11B located closer to the fixed side relative to the hollow 17 and having an outer peripheral surface of a relatively large diameter, and a movable-side large diameter portion 11C located closer to the movable side relative to the hollow 17 and having an outer peripheral surface of a relatively large diameter.

(8) Furthermore, in this embodiment, the outer diameter dimension d.sub.2 of the movable-side large diameter portion 11C is set smaller than the outer diameter dimension d.sub.1 of the fixed-side large diameter portion 11B (d.sub.1>d.sub.2) and the axial width w.sub.2 of the movable-side large diameter portion 11C is set smaller than the axial width w.sub.1 of the fixed-side large diameter portion 11B (w.sub.1>w.sub.2) among the sectioned three portions.

(9) In the shock-absorbing stopper 11 of the above-described configuration, when the shaft collides with the movable-side end portion 16, so that the load P is applied, whereby the movable-side end portion 16 is displaced in a direction approaching the fixed-side end portion 15, so that the elastic body 12 is compressed, the outer peripheral surface of the elastic body 12 tends to be radially outward swollen and deformed in the movable-side large diameter portion 11C to contact the inner peripheral surface 61a of the housing 61. However, the outer diameter dimension d.sub.2 of the movable-side large diameter portion 11C is set smaller than the outer diameter dimension d.sub.1 of the fixed-side large diameter portion 11B (d.sub.1>d.sub.2) as described above, and therefore a relatively large radial gap c is set between the movable-side large diameter portion 11C and the inner peripheral surface 61a of the housing 61.

(10) Moreover, the axial width w.sub.2 of the movable-side large diameter portion 11C is set smaller than the axial width w.sub.1 of the fixed-side large diameter portion 11B (w.sub.1>w.sub.2) as described above, and therefore, even when the movable-side large diameter portion 11C is swollen and deformed, the swollen and deformed amount can be suppressed.

(11) Accordingly, the radial gap c is set large due to d.sub.1>d.sub.2 of the former and the swollen and deformed amount is suppressed due to w.sub.1>w.sub.2 of the latter, and therefore the movable-side large diameter portion 11C does not contact the housing 61 even when the movable-side large diameter portion 11C is swollen and deformed or, even when the movable-side large diameter portion 11C contacts the housing 61, the contact surface pressure and the contact width can be reduced. Therefore, the sliding wear is hard to occur in the movable-side large diameter portion 11C.

Second Embodiment

(12) The first embodiment described above is configured so that the axial width w.sub.2 of the movable-side large diameter portion 11C is the sum of the axial width (thickness) w.sub.3 of the movable-side metal fitting 14 and the axial width w.sub.4 between the hollow 17 in the elastic body 12 and the movable-side metal fitting 14, and as the axial width w.sub.2 of the movable-side large diameter portion 11C becomes small, the axial width w.sub.4 between the hollow 17 in the elastic body 12 and the movable-side metal fitting 14 also becomes small in connection therewith. However, the axial width w.sub.2 of the movable-side large diameter portion 11C may be set only by the axial width (thickness) w.sub.3 of the movable-side metal fitting 14. In this case, the axial width w.sub.4 between the hollow 17 in the elastic body 12 and the movable-side metal fitting 14 is set to zero.

(13) In a shock-absorbing stopper 11 illustrated in FIG. 2 as a second embodiment, the axial width w.sub.2 of the movable-side large diameter portion 11C is set only by the axial width (thickness) w.sub.3 of the movable-side metal fitting 14 and the axial width between the hollow 17 in the elastic body 12 and the movable-side metal fitting 14 is set to zero from such a viewpoint.

(14) According to this configuration, the position of the hollow 17 further shifts to the movable-side as compared with the first embodiment, and therefore the elastic body 12 does not contact the housing 61 even when the elastic body 12 is swollen and deformed or, even when the elastic body 12 contacts the housing 61, the contact surface pressure and the contact width can be further reduced. Therefore, the sliding wear is harder to occur in the elastic body 12.

(15) The shape of the fixed-side metal fitting 13 or the movable-side metal fitting 14 is not particularly limited and may be a ring having a rectangular cross section or a ring having an L-shaped cross section as illustrated in FIG. 2 or the like besides the plate-like ring as illustrated in FIG. 1.

DESCRIPTION OF REFERENCE NUMERALS

(16) 11 shock absorbing stopper 11A small diameter portion 11B fixed-side large diameter portion 11C movable-side large diameter portion 12 elastic body 13 fixed-side metal fitting 14 movable-side metal fitting 15 fixed-side end portion 16 movable-side end portion 17 hollow 61 housing (mating component) 61a inner peripheral surface