JPH08200510A - Packing - Google Patents

Abstract

PURPOSE: To improve the sealability by improving the split structure of split bodies in a packing where a plurality of semi-circular split bodies are arranged in the circumferential direction to form an annular packing, and one end face in the axial direction of the packing and the inner circumferential surface are brought into contact with the counter member. CONSTITUTION: A recessed part 4 and a projected part 5 which are fitted to each other are provided on the end part in the circumferential direction of a pair of split bodies which are assembled with each other, and an end face part 6 to be pressed against which the projected part 5 is pressed when the pressure is applied is provided on a part of the inner surface of the recessed part 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packing used as a rod seal or the like in a hydraulic cylinder.

[0002]

2. Description of the Related Art Conventionally, as shown in FIGS. 5 to 8, a plurality of arc-shaped divided bodies 21 (three in the figure) are arranged in the circumferential direction to form an annular packing, and the packing is arranged in the axial direction of the packing. The end surface 22 and the inner peripheral surface 23 are respectively provided with the mating member 3
A packing which is in contact with 1, 32 and has a sealing function is known. This type of packing is used, for example, as a rod seal in a hydraulic cylinder. In this case, the mating members 31 and 32 are a cylinder tube and a rod, and as shown in FIG. It will be mounted in an annular mounting groove 33 provided on the inner peripheral surface. In addition, a garter spring (also referred to as a metal spring) 24 for gathering a plurality of divided bodies 21 in an annular shape is fitted on the outer peripheral side of the packing (see Japanese Utility Model Laid-Open No. 60-88166 or Japanese Utility Model Laid-Open No. 3-163). 5956
No. 0).

[0003]

However, in the above-mentioned conventional packing, the split surfaces 25 of the pair of split bodies 21 to be assembled with each other are such that the packing is axially different from the other as shown in FIG. 6 or 8. It is provided so as to linearly penetrate in the axial direction from the end surface 26 to the one axial end surface 22. Therefore, according to this conventional technique, the dividing surface 25 penetrating linearly in the axial direction is used as a leakage flow path,
There is a problem that a large amount of sealing fluid such as pressure oil leaks.

In view of the above points, the present invention relates to a packing in which a plurality of arc-shaped divided bodies are arranged in the circumferential direction to form an annular packing, and the axial one end surface and the inner peripheral surface of the packing come into contact with a mating member. The purpose of the present invention is to improve the dividing structure of the divided body so as to improve the sealing property.

[0005]

In order to achieve the above object, the packing of the present invention comprises a plurality of arc-shaped divided bodies arranged in the circumferential direction to form an annular packing, and the packing has an axial end surface and an inner surface. In a packing having a peripheral surface in contact with a mating member, a concave portion and a convex portion that are fitted to each other are provided at circumferential end portions of a pair of divided bodies that are combined with each other, and the convex portion is formed on a part of an inner surface of the concave portion when pressure is applied. It is decided to provide a pressed end face portion against which is pressed.

[0006]

In the packing of the present invention having the above-mentioned structure, the recesses and the protrusions fitted to each other are provided at the circumferential end portions of the pair of divided bodies to be combined with each other, and the pressure action is applied to a part of the inner surface of the recess. Since there is a pressed end surface portion against which the convex portion is sometimes pressed, when pressure due to the sealing fluid acts on the packing, the convex portion is pressed against the pressed end surface portion on the concave portion side, and there is a leakage flow path here. It will be prevented from being formed. Further, since the divided surface does not penetrate in the axial direction, the fluid that has entered the divided surface from the end face side will come out to the circumferential surface. Therefore, for this reason, it is possible to effectively prevent the sealing fluid such as the pressure oil from leaking from the split surface of the split body.

[0007]

Next, an embodiment of the present invention will be described with reference to the drawings.

As shown in FIGS. 1 to 4, in the packing according to the embodiment, a plurality (three in the drawing) of arc-shaped divided bodies 1 are arranged in the circumferential direction to form an annular packing. The axial one end surface 2 and the inner peripheral surface 3 are brought into contact with the mating members 31 and 32 respectively to perform a sealing action, and is further characterized in that the following configuration is provided.

That is, a concave portion 4 and a convex portion 5 which are fitted to each other are provided at the circumferential end portions of the pair of divided bodies 1 which are combined with each other, and the convex portion 5 is formed on a part of the inner surface of the concave portion 4 when pressure is applied. Is provided with a pressed end surface portion 6 against which
The pressed end surface portion 6 is provided in two steps of an outer peripheral side pressed end surface portion 6a and an inner peripheral side pressed end surface portion 6b, and the outer peripheral side pressed end surface portion 6a and the inner peripheral side pressed surface portion 6a. A step portion 7 is provided between the pressing end surface portions 6b, and the inner peripheral side pressed end surface portion 6b is arranged closer to the other axial end surface 8 side of the packing than the outer peripheral side pressed end surface portion 6a. The pressed end surface portion 6b of the above reaches the inner peripheral surface 3 of the packing. The pressed end surface portion 6a on the outer peripheral side and the pressed end surface portion 6b on the inner peripheral side are each formed in a plane shape perpendicular to the central axis of the packing.

The dividing surface 9 formed by the combination of the concave portion 4 and the convex portion 5 is constructed as follows. Axial one end surface 2 from the other axial end surface 8 of the packing
A first portion 9a extending axially toward. A second portion 9b that is continuous with the end of the first portion 9a and extends radially inward from the end. The concave portion 4 side of the second portion 9b is formed by the pressed end surface portion 6a on the outer peripheral side. A third portion 9c which is continuous with the end of the second portion 9b and which extends axially toward the other end surface 8 in the axial direction. That is,
It is the step portion 7 described above. The fourth portion 9 of the divided surface which is continuous with the end of the third portion 9c and extends radially inward from this to reach the inner peripheral surface 3.
d. The concave portion 4 side of the fourth portion 9d is formed by the inner peripheral side pressed end surface portion 6b.

Further, in this packing, instead of the garter spring 24 in the prior art, a rubber-like elastic body 10 such as an O-ring is fitted in a fitting groove 12 provided on an outer peripheral surface 11 of the packing with a predetermined tightening margin. It is fitted with.

As shown in FIG. 4, the packing having the above construction is mounted in an annular mounting groove 33 provided in the inner peripheral surface of the cylinder tube 31 which is a mating member, and the axial one end surface 2 is mounted. The inner peripheral surface 3 is brought into contact with one side wall 34 of the groove 33, and the inner peripheral surface 3 is brought into contact with the peripheral surface of the rod 32, which is another mating member, to achieve a sealing action. It produces a working effect.

That is, first of all, a concave portion 4 and a convex portion 5 which are fitted to each other are provided at the circumferential end portions of a pair of divided bodies 1 which are combined with each other, and a part of the inner surface of the concave portion 4 is subjected to pressure action. Since the pressed end surface portion 6 against which the convex portion 5 is pressed is provided, when the pressure due to the sealing fluid acts on the packing, the convex portion 5 is pressed toward the concave portion 4 by the pressed end surface portion 6.
To prevent the formation of a leak channel there. Therefore, it is possible to effectively prevent the sealing fluid such as the pressure oil from leaking from the divided surface 9 of the divided body 1, and it is possible to improve the sealing performance.

Secondly, since the pressed end surface portion 6 is provided in two steps, that is, inside and outside, of the pressed end surface portion 6a on the outer peripheral side and the pressed end surface portion 6b on the inner peripheral side, the pressed end surface portion 6 is formed. The sealing performance is high as compared with the case where 6 is a simple one stage.

Thirdly, a step portion 7 is provided between the pressed end surface portion 6a on the outer peripheral side and the pressed end surface portion 6b on the inner peripheral side, and the pressed end surface portion 6b on the inner peripheral side is pressed on the outer peripheral side. It is arranged closer to the other axial end 8 of the packing than the end surface 6a, that is, the fourth portion 9d of the dividing surface 9 is closer to the other axial end 8 of the packing than the second portion 9b. Therefore, when the entire divided surface 9 is viewed as one leak flow path,
The stepped portion 7, that is, the third portion 9c of the dividing surface 9, is provided with a portion in which the direction of the leakage flow is opposite to the arrangement of the pressure level, and a sealing fluid such as pressure oil flows through the bent flow path. Because it is difficult, the sealing performance is high.

Fourth, the pressed end surface portion 6b on the inner peripheral side reaches the inner peripheral surface 3 of the packing, that is, the fourth portion 9d of the dividing surface 9 reaches the inner peripheral surface 3 of the packing. .
Therefore, the dividing surface 9 starting from the other axial end surface 8 of the packing does not penetrate the packing in the axial direction, but is refracted midway to reach the inner peripheral surface 3, and the sealing fluid such as pressure oil is The sealing performance is high because it is difficult to flow in the bent flow path.

Fifth, the rubber-like elastic body 10 fitted in the fitting groove 12 provided on the outer peripheral surface 11 of the packing is also attached to the bottom wall 35 of the mounting groove 33 as shown in FIG. Contact
A seal is provided between the packing and the bottom wall 35. Therefore, also by this, the sealing performance is higher than before.

It should be noted that, as mentioned above, the fact that the dividing surface 9 is composed of the first to fourth portions 9a, 9b, 9c, 9d is an example up to bad, and the structure of the dividing surface 9 is as follows. There is no particular limitation. Moreover, the number of divisions of the divided body 1 is not particularly limited.

[0019]

The present invention has the following effects.

That is, in the packing of the present invention having the above-mentioned structure, the recesses and the protrusions fitted to each other are provided at the circumferential end portions of the pair of divided bodies to be assembled with each other, and a part of the inner surface of the recess is provided. Since there is a pressed end surface where the convex is pressed when pressure is applied, when pressure due to the sealing fluid acts on the packing, the convex is pressed against the pressed end surface on the concave side and leaks there. The passage is prevented from being formed. Therefore, it is possible to effectively prevent the sealing fluid such as pressure oil from leaking from the divided surfaces of the divided body, and it is possible to improve the sealing performance.

[Brief description of drawings]

FIG. 1 is a front view of a packing according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along the line AA in FIG.

FIG. 3 is an exploded perspective view of a combination part of divided bodies.

FIG. 4 is a half-cut sectional view showing a mounted state of the packing.

FIG. 5 is a front view of a packing according to a conventional example.

6 is a cross-sectional view taken along the line B-O-B in FIG.

FIG. 7 is an exploded perspective view of a combination portion of divided bodies.

FIG. 8 is a half-cut sectional view showing a mounted state of the packing.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Divided body 2 One end surface in the axial direction 3 Inner peripheral surface 4 Recessed portion 5 Convex portion 6 Pressed end surface portion 6a Outer peripheral pressed end surface portion 6b Inner peripheral pressed end surface portion 7 Stepped portion 8 Axial end surface 9 Divided surface 9a 1st part 9b 2nd part 9c 3rd part 9d 4th part 10 Rubber-like elastic body 11 Outer peripheral surface 12 Fitting groove 31,32 Counterpart member 33 Mounting groove 34 Side wall 35 Bottom wall

Claims (1)

[Claims] 1. An annular packing is formed by arranging a plurality of arc-shaped divided bodies (1) in a circumferential direction, and an axial direction one end surface (2) and an inner peripheral surface (3) of the packing are mated members (31).
In the packing to be brought into contact with (32), a concave portion (4) and a convex portion (5), which are fitted to each other, are provided at the circumferential end portions of the pair of divided bodies (1) which are combined with each other, and the inner surface of the concave portion (4) is provided. A packing characterized in that a pressed end surface portion (6) against which the convex portion (5) is pressed when pressure is applied is provided on a part of the packing.