Split gasket

Abstract

To provide a split gasket which does not need welding and a liquid gasket as well.SOLUTION: At both ends of split pieces (a first split piece 100A and a second split piece 100B), respective cutouts 102 are provided for forming holes through which shaft parts of bolts are inserted to fix two members (a case 10 and a cover 20). At both ends of the split pieces, respective positioned protrusions 103 are provided which are positioned in the opening part of a screw hole 12 provided in one of the two members.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a split gasket.

Background Art

[0002] Conventionally, as a gasket for sealing a gap between end faces of two members fixed by a plurality of bolts, a gasket including a metal gasket body is known. Such a gasket is obtained by performing punching on a material having a metal plate. Usually, since the gasket is annular, the inner portion when punching the gasket from the material becomes waste material. Therefore, particularly in the case of a large gasket, a large amount of waste material is generated. As a countermeasure, a technique for manufacturing an annular gasket by using a plurality of split pieces and fixing both ends of each split piece is known. In the case of a method of fixing both ends of each split piece by welding, unevenness occurs in the welded portion, and in the case of a method of overlapping and bonding the ends of the split pieces, a multilayer structure is formed. Therefore, the applicant of the present application has proposed a technique of bonding end faces of adjacent split pieces with a liquid gasket (see Patent Document 1).

[0003] According to the technique disclosed in Patent Document 1, stable sealing performance can be obtained. However, management such as storage of the liquid gasket is required, and a step of applying the liquid gasket is also required, resulting in high costs.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present invention provides a split gasket that does not require welding and does not require a liquid gasket.

Means for Solving the Problem

[0006] The present invention employs the following means to solve the above problems.

[0007] That is, the split gasket of the present invention comprises a plurality of split pieces each having at least a plate-shaped metal gasket body, and is arranged between two members in a state where the end faces at both ends of adjacent split pieces are in contact with each other, thereby sealing the gap between the end faces of the two members. The split gasket is characterized in that notches for forming holes through which the shaft portions of bolts for fixing the two members are inserted are respectively provided at both ends of the split piece, and positioning protrusions that are positioned with respect to the openings of screw holes provided in one of the two members are respectively provided at both ends of the split piece.

[0008] According to the present invention, when arranging the split piece on one of the two members, the split piece can be accurately and easily installed at a desired position. Accordingly, the gap between the end faces of adjacent split pieces can be almost eliminated. In this way, the combination of the ability to accurately position the split pieces and the ability to almost eliminate the gap between the end faces of adjacent split pieces enables the end faces of adjacent split pieces to be stably brought into contact with each other when a compressive strain is generated in the split pieces. Therefore, there is no need to weld or adhere with a liquid seal or the like in order to bring the end faces of the split pieces into contact with each other. Further, a configuration is adopted in which notches for forming holes through which the shaft portions of bolts for fixing the two members are inserted are respectively provided at both ends of the split piece so that when the two members are fastened by bolts, both ends of the split piece are firmly fixed. As a result, adjacent split pieces are firmly fixed in a positioned state. Further, a compressive strain can be more reliably generated in the vicinity of the end faces of the split pieces. Note that the positioning protrusions are preferably provided in the notches.

[0009] On the split piece, a bead for sealing that adheres to one of the two members is provided along the extending direction of the split piece, and the bead may be provided so as to branch toward both side surfaces of the split piece near the notch so as not to contact the notch.

[0010] Thus, even when adopting a configuration in which a bead for enhancing the sealing property is provided, when the split piece is arranged on one of the two members, the seating property of the split piece with respect to one member near the end face of the split piece can be enhanced. That is, the posture of the split piece near the end face with respect to one member can be stabilized. Further, since the branched portions of the bead are compressed, the end faces of adjacent split pieces are deformed so as to approach each other more closely, and thus the gap between these end faces can be more surely eliminated.

Advantages of the Invention

[0011] As described above, according to the present invention, it is possible to provide a split gasket that does not require welding and also does not require a liquid gasket.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0013] With reference to the drawings below, embodiments for carrying out the present invention will be illustratively described in detail based on examples. However, dimensions, materials, shapes, relative arrangements, etc. of the components described in these examples are not intended to limit the scope of the present invention only to those, unless otherwise specifically described.

[0014] (Example 1) With reference to FIGS. 1 to 4, the split gasket according to Example 1 of the present invention will be described. FIG. 1 is a schematic view of a sealing structure including the split gasket according to Example 1 of the present invention, where FIG. 1(a) is a plan view of an apparatus including the sealing structure, and FIG. 1(b) is a side view of the apparatus. In FIG. 1, a part of its internal structure is shown in a dotted line by perspective. FIG. 2 is a schematic view of a split gasket according to the prior art, where FIG. 2(a) shows a state where adjacent split pieces are not in contact with each other, and FIG. 2(b) shows a state where adjacent split pieces are in contact with each other. FIG. 3 is an explanatory diagram of the mechanism of a split gasket according to the prior art, where FIG. 3(a) is a schematic cross-sectional view explaining the assembly procedure for fixing two members, and FIG. 3(b) is a schematic cross-sectional view showing the state where the two members are fixed. FIG. 4 is an explanatory diagram of the split gasket according to Example 1 of the present invention. FIG. 4(a) is a schematic view of the split gasket, showing a part of the state where adjacent split pieces are not in contact with each other in a plan view. FIG. 4(b) is a plan view showing a part of the state where the split piece is installed on one of the two members. FIG. 4(c) is a cross-sectional view taken along line BB in FIG. 4(b). In each figure, for the purpose of emphasizing the characteristic configuration of the present invention, the scale is different from that of a general commercial product.

[0015] <Sealing structure> With reference to FIG. 1, the sealing structure including the split gasket 100 according to Example 1 of the present invention will be described. The apparatus shown in FIG. 1 includes a case 10 having a housing portion 11 for accommodating various members, and a lid 20 for closing the opening of the case 10. And in this apparatus, a split gasket 100 is provided which is arranged between these two members (the case 10 and the lid 20) to seal the gap between the end faces of these two members. Thus, the above two members and the split gasket 100 constitute a sealing structure.

[0016] And the above two members are configured to be fixed by a plurality of bolts 30. More specifically, a plurality of threaded holes 12 having female threads that are screwed with male threads formed on the shaft portions of the bolts 30 are provided on the end faces of the four side walls constituting the case 10. Further, the lid 20 is provided with a plurality of recesses 21 having portions that serve as seat surfaces for the heads of the bolts 30 and insertion holes 22 (see FIG. 3) through which the shaft portions of the bolts 30 are inserted. With such a configuration, the two members can be fixed by the plurality of bolts 30.

[0017] <Basic Configuration of Split Gasket (Prior Art)> Prior to the description of the split gasket 100 according to the present embodiment, the basic configuration (prior art) of the split gasket will be described with reference to FIGS. 2 and 3. The split gasket 100X shown in FIGS. 2 and 3 includes a plurality of split pieces each having at least a plate-shaped metal gasket body 110. In the present embodiment, the split gasket 100X is constituted by two split pieces. Hereinafter, for convenience, the two split pieces are referred to as a first split piece 100A and a second split piece 100B, respectively. And in the split gasket 100X, the end faces of both ends of adjacent split pieces (the first split piece 100A and the second split piece 100B) are arranged between two members (the case 10 and the lid 20) in a state of being in contact with each other, so as to seal the gap between the end faces of these two members.

[0018] Here, the case where the split gasket 100X is constituted by two split pieces is shown, but the split gasket of the present invention also includes the case where it is constituted by three or more split pieces. Also, the first split piece 100A and the second split piece 100B are constituted by members having the same dimensional shape, but in the present invention, the dimensional shapes of the plurality of split pieces constituting the split gasket may be different. In the case of a gasket having a metal gasket body, it can be obtained by punching at least a material having a metal plate. In the case of the split gasket 100X, the split pieces can be manufactured by punching the material, so that waste materials can be significantly reduced.

[0019] The first split piece 100A and the second split piece 100B each include a metal gasket body 110 and an elastic body 120 provided on the surface of the gasket body 110. For example, stainless steel, cold-rolled steel sheet, galvanized steel sheet, and aluminum plywood can be suitably used as the material of the gasket body 110. In addition, a synthetic rubber sheet (including foamed rubber) containing at least one of nitrile rubber, styrene butadiene rubber, fluororubber, acrylic rubber, and silicone rubber can be suitably used as the elastic body 120. Here, a configuration in which the elastic body 120 is provided on one side of the gasket body 110 is shown, but the present invention also includes a configuration in which elastic bodies are provided on both sides of the gasket body, and a configuration in which no elastic body is provided. When a member with a rough surface is used for the two members that constitute the sealing structure, it is desirable to configure the elastic body to be in close contact with each other. When a split piece having an elastic body is used, the split piece can be obtained by punching a material in which an elastic body is provided on the surface of a metal plate.

[0020] In addition, a base treatment agent layer 130 is provided between the gasket body 110 and the elastic body 120. This prevents the elastic body 120 from peeling off from the gasket body 110. However, depending on the usage environment, etc., a configuration in which the primer layer 130 is not provided may also be adopted.

[0021] The first split piece 100A and the second split piece 100B each have a plurality of holes 101 (three in the illustrated example) through which the shanks of the bolts 30 that secure the two components together are inserted. Also, the first split piece 100A and the second split piece 100B each have at both ends a notch 102 for forming a hole through which the shanks of the bolts 30 that secure the two components together are inserted.

[0022] <Mechanism of split gasket 100X> The mechanism of the split gasket 100X will be described. First, a plurality of split pieces (the first split piece 100A and the second split piece 100B) are arranged on the end face on the opening side of the case 10, which is one of the two members (see Fig. 3(a)). As shown in the figure, when the first split piece 100A and the second split piece 100B are not compressed by the case 10 and the lid 20, a gap is formed between these end faces.

[0023] Then, when the case 10 and the lid 20 are fixed by bolts 30, compressive strain occurs in the split pieces (the first split piece 100A and the second split piece 100B). That is, since these split pieces are compressed by the case 10 and the lid 20 from both sides, a deformation occurs such that they extend in a direction perpendicular to the compression direction. As a result, among the adjacent split pieces (the first split piece 100A and the second split piece 100B), portions on both sides of the notch 102 on the end faces of the split pieces come into contact with each other (see Figs. 2(b) and 3(b)). In Fig. 3(b), in the state where the case 10 and the lid 20 are fixed by bolts 30, the bolts 30 are omitted to show the state of the split gasket 100 more clearly. As shown in the figure, since holes through which the shaft portions of the bolts 30 are inserted are formed by the notches 102 provided in the adjacent split pieces respectively, the split pieces do not have an adverse effect on the bolts 30.

[0024] As described above, by compressing the split pieces with two members, the end faces of the adjacent split pieces can be brought into contact with each other due to the compressive strain. However, since the distance by which the split pieces extend due to the compressive strain is short, it may be difficult to obtain sufficient sealing performance. That is, since a plurality of split pieces are arranged on one of the two members, generally, it is necessary to provide a gap (clearance) between the end faces of the adjacent split pieces. Considering the workability when arranging the split pieces, in the case of a configuration such as the split gasket 100X, there is a limit to narrowing this gap, and it may be difficult to obtain sufficient sealing performance depending only on the compressive strain. Therefore, in the gasket 100 according to this embodiment, a configuration that can obtain sufficient sealing performance is adopted as described below.

[0025] <Split gasket according to this embodiment> Referring to FIG. 4, the split gasket 100 according to this embodiment will be described. Regarding the basic configuration, since it is the same as the above-described prior art, the same reference numerals are given to the same components, and the detailed description thereof will be omitted as appropriate.

[0026] Also in the split gasket 100 according to this embodiment, a first split piece 100A and a second split piece 100B are provided. In the split gasket 100 according to this embodiment, it is different from the split gasket 100X only in that a positioning projection 103 is provided with respect to the configuration of the split gasket 100X described above. Therefore, also in the first split piece 100A and the second split piece 100B, although not particularly shown, both include a metal gasket body, an elastic body, and an undercoat treatment agent layer. In FIG. 4(c), since the split gasket 100 is simply shown, the elastic body and the undercoat treatment layer are omitted. Also, the point that a configuration in which the elastic body is provided on both surfaces of the gasket body may be adopted, the point that a configuration in which the elastic body is not provided may be adopted , and the point that a configuration in which the undercoat treatment agent layer is not provided may be adopted is as described above. Also, in the first split piece 100A and the second split piece 100B according to this embodiment, a plurality of holes (not shown in FIG. 4) through which the shaft portion of the bolt 30 passes and a notch 102 for forming a hole through which the shaft portion of the bolt 30 passes are provided.

[0027] And, at both ends of the split pieces (the first split piece 100A and the second split piece 100B) according to this embodiment, positioning projections 103 are respectively provided which are positioned with respect to the opening of a screw hole 12 having a female screw provided on one of the two members (case 10). This positioning projection 103 is provided in the notch 102. At least one positioning projection 103 may be provided, but in this embodiment, a configuration in which two positioning projections 103 are provided in the notch 102 is adopted. In this way, by providing the positioning projections 103 at a plurality of locations, the movement of the split pieces is restricted, so that the split pieces can be positioned more accurately.

[0028] Also in this embodiment, first, a plurality of divided pieces (first divided piece 100A and second divided piece 100B) are arranged on the end face on the opening side of the case 10, which is one of the two members (see Fig. 4(b)). In this embodiment, by aligning the positioning protrusion 103 provided on the divided piece with the edge of the opening of the screw hole 12, the divided piece can be easily and accurately positioned with respect to the case 10 (see Fig. 4(b)(c)). As shown in the figure, the positioning protrusion 103 is fixed so as to enter the screw hole 12. By screwing the male thread of the bolt 30 into the female thread of the screw hole 12, the tip of the positioning protrusion 103 is sandwiched between the outer peripheral surface of the shaft portion of the bolt 30 and the inner peripheral surface of the screw hole 12, and the tip can be configured to be crushed. By adopting such a configuration, the divided piece can be fixed more firmly, and the displacement when the two members (case 10 and lid 20) are compressed can be suppressed.

[0029] In this embodiment, since the first divided piece 100A and the second divided piece 100B can be accurately installed at desired positions, in a state where the case 10 and the lid 20 are not compressed, the gap between the end faces of the first divided piece 100A and the second divided piece 100B can be almost eliminated. That is, like the prior art described above, almost no clearance needs to be provided. Then, when the case 10 and the lid 20 are fixed by the bolt 30, compressive strain occurs in the divided pieces (first divided piece 100A and second divided piece 100B). As a result, in the adjacent divided pieces (first divided piece 100A and second divided piece 100B), the portions on both sides of the notch 102 on the end faces of the divided pieces come into contact more reliably.

[0030] <Advantages of the split gasket according to this embodiment> According to the split gasket 100 according to this embodiment, when arranging the split pieces on one of the two members (the case 10 and the lid 20), the split pieces can be accurately and easily installed at desired positions. Accordingly, it is possible to set the gaps between the end faces of adjacent split pieces to be almost eliminated. In this way, the combination of the ability to accurately position the split pieces and the ability to set the gaps between the end faces of adjacent split pieces to be almost eliminated enables the end faces of adjacent split pieces to be more reliably brought into contact with each other when compressive strain is generated in the split pieces.

[0031] Therefore, in order to bring the end faces of adjacent split pieces into contact with each other, there is no need for welding, nor is there a need for adhesion with a liquid seal or the like. Accordingly, the number of assembly steps (manufacturing steps) can be reduced. Also, management of the liquid seal and the like becomes unnecessary. Furthermore, by using the split gasket 100 instead of an annular gasket, waste materials can be reduced. As described above, costs can be reduced.

[0032] Also, a configuration is adopted in which notches 102 for forming holes through which the shaft portions of bolts 30 for fixing the two members (the case 10 and the lid 20) are inserted are respectively provided at both ends of the split pieces. Therefore, when the two members are fastened by the bolts 30, both ends of the split pieces are firmly fixed. That is, since the fastening force by the bolts 30 becomes particularly large in the vicinity of the shaft portions of the bolts 30, the vicinity of both ends of the split pieces is firmly fixed. Thereby, adjacent split pieces are firmly fixed in a positioned state. Also, compressive strain can be more reliably generated in the vicinity of the end faces of the split pieces.

[0033] (Example 2) FIG. 5 shows Example 2 of the present invention. In this example, a configuration is shown in which a bead for sealing is provided on the split pieces in the configuration shown in Example 1 above. Since other configurations and operations are the same as those in Example 1, the same reference numerals are given to the same component parts, and the description thereof is omitted as appropriate.

[0034] FIG. 5 is an explanatory view of the split gasket according to Embodiment 2 of the present invention. FIG. 5(a) is a schematic view of the split gasket, showing a state where adjacent split pieces are not in contact with each other in a plan view. FIG. 5(b) is a cross-sectional view taken along line CC in FIG. 5(a). FIG. 5(c) is a schematic view of the split gasket, showing a state where adjacent split pieces are in contact with each other in a plan view.

[0035] In the split pieces (the first split piece 100A and the second split piece 100B) according to this embodiment, a sealing bead 104 that adheres to one of the two members (here, the case 10) is provided along the extending direction of the split pieces. Since the sealing bead provided on the metal gasket itself is a known technique, a detailed description thereof is omitted. By providing the bead 104, the surface pressure peak can be increased and the sealing performance can be enhanced as compared with the case where the bead is not provided. In this embodiment, the bead 104 is provided so as to protrude toward the side where the elastic body 120 is provided. However, a configuration in which the bead is provided so as to protrude toward the side where the elastic body 120 is not provided may be adopted. Also, as described in Embodiment 1, configurations in which elastic bodies are provided on both surfaces of the gasket body and in which no elastic body is provided can be adopted.

[0036] And the bead 104 according to this embodiment is provided so as to branch out toward both side surfaces of the split piece so as not to contact the notch 102 in the vicinity of the notch 102 (see the branched portion 104X). In addition, at least a part of the branched portion 104X is provided directly below the head of the bolt 30. In FIG. 5(c), the position of the head of the bolt 30 is indicated by a dotted line.

[0037] Also in this embodiment, first, a plurality of split pieces (first split piece 100A and second split piece 100B) are arranged on the end face on the opening side of the case 10, which is one of the two members. Also in this embodiment, as in the first embodiment, even when the first split piece 100A and the second split piece 100B are not compressed by the case 10 and the lid 20, the gap between the end faces of the first split piece 100A and the second split piece 100B can be almost eliminated. Then, when the case 10 and the lid 20 are fixed by the bolt 30, compressive strain is generated in the split pieces (first split piece 100A and second split piece 100B). As a result, as in the first embodiment, in the adjacent split pieces (first split piece 100A and second split piece 100B), the portions on both sides of the notch 102 in the end faces of the split pieces come into contact with each other more reliably (see Fig. 5(b)).

[0038] Also in the split gasket 100S according to this embodiment configured as described above, the same effects as those in the first embodiment can be obtained. Further, in this embodiment, since the configuration of providing the bead 104 for sealing is adopted, the sealing performance can be enhanced. And in the bead 104 according to this embodiment, by providing the branch portion 104X, when the split pieces are arranged on one of the two members (here, the case 10), the seating property of the split pieces on one of the members in the vicinity of the end faces of the split pieces can be enhanced. That is, the posture of the split pieces in the vicinity of the end faces can be stabilized with respect to one of the members. Also, when the branch portion 104X in the bead 104 is compressed, the end faces of the adjacent split pieces are deformed so as to approach each other more closely, so that the gap between these end faces can be more reliably eliminated. As a result, the end faces of the adjacent split pieces can be brought into contact with each other more stably. Also, when the branch portion 104X in the bead 104 is compressed, the end faces of the adjacent split pieces are deformed so as to approach each other more closely, so that the gap between these end faces can be more reliably eliminated. As a result, the end faces of the adjacent split pieces can be brought into contact with each other more stably.

[0039] (Others) In each of the above embodiments, the configuration in the case where the planar shape (the planar shapes of the inner peripheral surface and the outer peripheral surface) of the split gasket is substantially rectangular is shown, but the planar shape of the split gasket of the present invention is not limited. For example, in addition to circular and elliptical planar shapes, various shapes can be adopted according to the location where the split gasket is used.

Explanation of Reference Numerals

[0040] 10: Case 11: Accommodating part 12: Meneji 20: Lid 21: Concave part 22: Insertion hole 30: Bolt 100, 100X, 100S: Split gasket 100A: First split piece 100B: Second split piece 101: Hole 102: Notch 103: Positioning projection 104: Bead 104X: Branch part 110: Gasket body 120: Elastic body 130: Base treatment agent layer

Claims

1. A split gasket comprising a plurality of split pieces each having at least a plate-shaped metal gasket body, and disposed between two members in a state where the end faces of both ends of adjacent said split pieces are in contact with each other, thereby sealing the gap between the end faces of said two members, notches for forming holes through which the shaft portions of bolts for fixing said two members are inserted are respectively provided at both ends of said split pieces, and positioning protrusions are respectively provided at both ends of said split pieces so as to be positioned with respect to the openings of screw holes provided in one of said two members. A split gasket characterized by this.

2. The split gasket according to claim 1, wherein the positioning protrusion is provided in the notch.

3. A seal bead that adheres to one of said two members is provided on said split piece along the extending direction of said split piece, and the bead is provided so as to branch out toward both side surfaces of said split piece so as not to contact the notch in the vicinity of the notch. The split gasket according to claim 1 or 2, characterized by this.

Images