JP6360743B2 - gasket - Google Patents

Description

  The present invention relates to a gasket.

  Conventionally, a gasket composed of a metal mesh material and expanded graphite is known as a gasket used for a joint portion of a pipe. For example, the gasket described in Patent Document 1 is composed of a metal mesh material made of stainless steel or the like and an inorganic material such as an expanded graphite sheet.

  The gasket described in Patent Document 1 is a sheet-shaped inorganic material wrapped with a metal mesh and manufactured into a cylindrical shape by press molding, and has a sealing surface for the pipe at both axial end surfaces. It wasn't too much. Therefore, there was room for improvement from the viewpoint of enhancing the sealing performance.

JP-A-7-113469

  This invention is made | formed in view of such a situation, and it aims at providing the gasket which can ensure high sealing performance.

  The invention according to claim 1 is a gasket formed by compressing a strip-shaped composite body having a metal mesh material and expanded graphite surrounded by the metal mesh material into a cylindrical shape after being wound in a spiral shape. The first seal portion disposed at one axial end portion and the second seal portion disposed at the other axial end portion, and the cross-sectional shape in which the complex in the bent state overlaps in the radial direction And at least one of the composites includes a bent portion that is bent in an acute angle in the radial direction.

  According to this configuration, the contact surface pressure when the first seal portion comes into contact with a corresponding member to be sealed using the repulsive force caused by the bending of the composite, particularly the composite including the bent portion, And a contact surface pressure when the said 2nd seal | sticker part contacts the sealing object member corresponding to this can be increased. Therefore, high sealing performance can be secured for the first seal portion and the second seal portion.

  The invention according to claim 2 is the gasket according to claim 1, wherein the first seal portion has a first seal surface that tapers toward one end surface in the axial direction, and the second seal portion. The cross-sectional shape is formed by compressing the composite so that the second seal surface is tapered toward the other end surface side in the axial direction.

  According to this configuration, the contact surface pressure between the first seal portion and the sealing target member can be further increased. Further, the contact surface pressure between the second seal portion and the sealing target member can be further increased.

  ADVANTAGE OF THE INVENTION According to this invention, the gasket which can ensure high sealing performance can be provided.

It is sectional drawing which shows the state at the time of use of the gasket which concerns on one Embodiment of this invention. It is a front view of the gasket of FIG. It is AA arrow sectional drawing of FIG. FIG. 4 is a partially enlarged view of FIG. 3. It is a front view of the composite_body | complex used for the gasket of FIG. It is a perspective view which shows the state in the middle of the manufacturing process of the gasket of FIG. It is a schematic sectional drawing which shows the state in the middle of the manufacturing process of the gasket of FIG.

  A preferred embodiment of the present invention will be described with reference to the drawings.

  In FIG. 1, the state at the time of use of the gasket 1 which concerns on one Embodiment of this invention is shown. FIG. 2 shows a front view of the gasket 1. FIG. 3 is a cross-sectional view taken along the line AA in FIG. FIG. 4 shows a partially enlarged view of FIG.

  As shown in FIG. 1, the said gasket 1 is used for the joint part of exhaust pipes (1st piping 3 and 2nd piping 4), such as a motor vehicle, for example. When the exhaust pipe is used for a joint portion or the like, the gasket 1 is configured to seal the gap between the end of the first pipe 3 and the end of the second pipe 4 facing each other. It is interposed between the pipe 3 and the second pipe 4.

  The gasket 1 is formed in an annular shape as shown in FIGS. 1, 2, and 3. When the gasket 1 is used, the gasket 1 is attached in an externally fitted state to the end of the first pipe 3. An annular first contact portion (member to be sealed) 5 provided integrally (or separately) at the end of the second pipe and an annular first contact portion (member to be sealed) provided integrally (or separately) at the end of the second pipe 4. The two contact portions (members to be sealed) 6 are sandwiched between them.

  As exaggeratedly shown in FIG. 4, the gasket 1 is configured using a metal mesh material 11 and expanded graphite 12. The gasket 1 is formed by compression molding into a cylindrical shape (annular shape) after a long strip-shaped composite body 13 having the metal mesh material 11 and the expanded graphite 12 surrounded by the metal mesh material 11 is wound in a spiral shape. . A method for manufacturing the gasket 1 will be described later.

  In the gasket 1, the composite 13 exists so as to overlap in multiple layers in the radial direction, and the metal wire forming the metal mesh material 11 and the expanded graphite 12 are mixed. In the figure, the detailed arrangement of these metal wires and expanded graphite is omitted as appropriate.

  The gasket 1 includes a seal portion for preventing leakage of fluid from the flow path 15 in the first pipe 3 and the second pipe 4 connected to each other. In the present embodiment, the gasket 1 includes a first seal portion 21 and a second seal portion 22 as shown in FIGS. 1, 2, 3, and 4.

  The first seal portion 21 is provided at one end in the axial direction of the gasket 1 and is disposed on the radially outer side of the gasket 1. The first seal portion 21 has a first seal surface 23 that tapers toward one end surface 24 in the axial direction of the gasket 1.

  The first seal surface 23 can be in contact with the first contact portion 5 (specifically, the inclined annular facing surface 8), and the outer periphery of the composite 13 in a multiple winding state after compression molding. It is provided in the part located in the side. The first seal surface 23 is disposed between the one axial end surface 24 disposed to face the first contact portion 5 and the outer peripheral surface 25 of the gasket 1.

  In the present embodiment, the first seal surface 23 is tapered so as to gradually decrease in diameter from the outer peripheral surface 25 (center of the gasket 1 in the axial direction) toward the one end surface 24 in the axial direction. It is formed in a shape. Here, as shown in FIG. 4, the one axial end surface 24 extends linearly in the radial direction, and the outer peripheral surface 25 extends linearly in the axial direction.

  The first seal surface 23 is connected to the one end surface 24 in the axial direction at a reduced diameter side end portion 27 located on one end side in the axial direction. The diameter-reduced side end 27 of the first seal surface 23 is a curve that protrudes outward in one axial direction of the gasket 1 and radially outward in a cross section including the axial center 26 of the gasket 1. It is formed so as to exhibit a shape (R shape).

  As shown in FIG. 1, the gasket 1 is sandwiched between the first contact portion 5 and the second contact portion 6 that are close to each other in the axial direction, and the first pipe 3 and the second pipe 4. When the first seal portion 21 is pressed against the first contact portion 5 so as to be compressed and deformed, the first seal portion 23 (the opposed surface) is pressed against the first contact portion 5. 8).

  On the other hand, the second seal portion 22 is provided at the other axial end portion of the gasket 1 and is disposed on the radially outer side of the gasket 1. The second seal portion 22 has a second seal surface 28 that tapers toward the other axial end surface 29 of the gasket 1.

  The second seal surface 28 can be in contact with the second contact portion 6 (specifically, the inclined annular facing surface 9), and the outer periphery of the complex 13 in a multiple winding state after compression molding. It is provided in the part located in the side. The second seal surface 28 is disposed between the axial direction other end surface 29 disposed opposite to the second contact portion 6 and the outer peripheral surface 25 of the gasket 1.

  In the present embodiment, the second seal surface 28 tapers so as to gradually reduce the diameter from the outer peripheral surface 25 (center of the gasket 1 in the axial direction) toward the other axial end surface 29. It is formed in a shape. Here, as shown in FIG. 4, the other axial end surface 29 is formed to extend linearly in the radial direction.

  The second seal surface 28 is connected to the other axial end surface 29 at a reduced diameter side end 30 located on the other axial end side. The diameter-reduced side end portion 30 of the second seal surface 28 is a curve that protrudes outward in the axial direction other side and radially outward of the gasket 1 in a cross section including the axial center 26 of the gasket 1. It is formed so as to exhibit a shape (R shape).

  As shown in FIG. 1, when the gasket 1 is used for a joint portion of the first pipe 3 and the second pipe 4, the second seal portion 22 is compressed to the second contact portion 6. By being pressed so as to be deformed, the second seal surface 28 is brought into pressure contact with the second contact portion 6 (the opposed surface 9).

  As shown in FIG. 4, the gasket 1 has a cross-sectional shape in which the composite 13 in a bent state by the compression molding described above overlaps in the radial direction of the gasket 1. In the gasket 1, at least one of the composites 13 includes a bent portion 16 that is bent at an acute angle in the radial direction.

  In the present embodiment, the composite 13 includes an inner peripheral composite 13A, a plurality of intermediate composites 13B, and an outer peripheral composite 13C. The inner peripheral side composite 13A, the plurality of intermediate composites 13B, and the outer peripheral side composite 13C are stacked in this order from the radially inner peripheral side to the outer peripheral side of the gasket 1.

  The plurality of intermediate composite bodies 13B are bent at a different degree of bending from the adjacent composite bodies 13, and include a bent portion protruding inward in the radial direction at an intermediate portion in the axial direction. At least one of the plurality of intermediate composites 13 is bent in a V-shaped cross section at an intermediate portion in the axial direction so that the bent portion becomes the bent portion 16.

  The bent portion 16 has inclined surfaces 17 and 18 that face each other. The bent portion 16 has an angle formed by the inclined surfaces 17 and 18 so that the inclined surfaces 17 and 18 are brought close to each other (or brought into contact with each other) at a predetermined interval in a cross section including the axis 26 of the gasket 1. It is formed to have an acute angle shape.

  Moreover, the said bending part 16 is formed in the symmetrical shape in the axial center direction of the said gasket 1 in this embodiment. The bent portion 16 is disposed at the central portion in the axial center direction of the gasket 1 so as to exist at a substantially equidistant position from each of the first seal portion 21 and the second seal portion 22.

  With this configuration, when the gasket 1 is attached to the end of the first pipe 3 so as to be sandwiched between the first contact portion 5 and the second contact portion 6, the composite body 13, the contact surface pressure when the first seal portion 21 comes into contact with the opposed surface 8 at the first seal surface 23 by utilizing the repulsive force caused by the bending of the composite including the bent portion, and It is possible to increase the contact surface pressure when the second seal portion 22 comes into contact with the facing surface 9 at the second seal surface 28. Therefore, high sealing performance can be secured for the first seal portion 21 and the second seal portion 22.

  In the present embodiment, the first seal portion 21 has the first seal surface 23 that tapers toward one end surface in the axial direction when the gasket 1 is manufactured (a compression molding step described later). And the compression molding of the said composite body 13 is performed so that the said 2nd seal | sticker part 22 may have the 2nd seal | sticker surface 28 tapering toward the axial center direction other end surface side. Thereby, the cross-sectional shape is formed.

  With such a configuration, according to the gasket 1, the contact surface pressure between the first seal portion 21 and the facing surface 8 can be further increased. Moreover, the contact surface pressure between the second seal portion 22 and the facing surface 9 can be further increased. As a result, the sealing performance of the first seal portion 21 and the second seal portion 22 can be improved.

  In the present embodiment, as shown in FIGS. 2, 3, and 4, the first seal portion 21 has a first protrusion that protrudes outside the gasket 1 in addition to the first seal surface 23. A portion 31 is provided. The first seal portion 21 is configured to exhibit a sealing function using the first seal surface 23 and the first projecting portion 31.

  Specifically, the first projecting portion 31 is provided in a portion located on the outermost periphery of the composite 13 in a multiple winding state after compression molding. The first protrusion 31 is disposed between the first seal surface 23 and the outer peripheral surface 25 of the gasket 1 and is formed so as to be continuous with the first seal surface 23 and the outer peripheral surface 25.

  The first protruding portion 31 is formed to protrude in a direction intersecting with the first seal surface 23. In the present embodiment, the first protruding portion 31 is formed in a pointed shape so as to protrude radially outward from the first seal surface 23 and to protrude in one axial direction from the outer peripheral surface 25. Yes.

  When the gasket 1 is sandwiched between the first contact portion 5 and the second contact portion 6, the first seal portion 21 is pressed against the facing surface 8 of the first contact portion 5, The first seal portion 23 and the first protrusion 31 are in pressure contact with the first contact portion 5 while being compressed and deformed radially inward of the gasket 1 so that the one protrusion 31 is crushed. .

  With such a configuration, when the first seal portion 21 is brought into pressure contact with the first contact portion 5 (the facing surface 8) in order to exert a sealing function, the facing surface 8 is crushed while the first projecting portion 31 is crushed. At the same time, the first seal surface 23 can be brought into contact with the facing surface 8, and the first seal portion 21 can be brought into contact with the first contact portion 5 with a higher contact surface pressure. It becomes. Therefore, the sealing performance of the first seal portion 21 can be improved.

  Further, in the present embodiment, as shown in FIGS. 3 and 4, the second seal portion 22 includes a second projecting portion 32 projecting outside the gasket 1 in addition to the second seal surface 28. Have. The second protrusion 32 is configured to exhibit a sealing function using the second seal surface 28 and the second protrusion 32.

  Specifically, the second projecting portion 32 is provided in a portion located on the outermost periphery of the composite 13 in a multiple winding state after compression molding. The second protrusion 32 is disposed between the second seal surface 28 and the outer peripheral surface 25 of the gasket 1 and is formed so as to be continuous with the second seal surface 28 and the outer peripheral surface 25.

  The second projecting portion 32 is formed so as to project in a direction intersecting with the second seal surface 28. In the present embodiment, the second projecting portion 32 is formed in a pointed shape so as to project radially outward from the second seal surface 28 and project from the outer peripheral surface 25 to the other axial direction. Yes.

  When the gasket 1 is sandwiched between the first contact portion 5 and the second contact portion 6, the second seal portion 22 is pressed against the facing surface 9 of the second contact portion 6, 2 The second seal portion 28 and the second protrusion 32 are pressed against the second contact portion 6 while being compressed and deformed radially inward of the gasket 1 so that the protrusion 32 is crushed. .

  With this configuration, when the second seal portion 22 is brought into pressure contact with the second contact portion 6 (the facing surface 9) in order to exert a sealing function, the facing surface 9 is crushed while the second projecting portion 32 is crushed. At the same time, the second seal surface 28 can be brought into contact with the facing surface 9, and the second seal portion 22 can be brought into contact with the second contact portion 6 with a higher contact surface pressure. It becomes. Therefore, the sealing performance of the second seal portion 22 can be enhanced.

  In the present embodiment, as shown in FIGS. 2, 3, and 4, a first chamfered portion 36 is provided between the one axial end surface 24 of the gasket 1 and the inner peripheral surface 35 of the gasket 1. Is formed. The first chamfered portion 36 has an inclined surface that gradually increases in diameter from the inner peripheral surface 35 side toward the one axial end surface 24, and is provided over the entire circumference of the gasket 1.

  In this embodiment, as shown in FIGS. 3 and 4, a second chamfered portion 37 is formed between the other axial end surface 29 of the gasket 1 and the inner peripheral surface 35 of the gasket 1. The second chamfered portion 37 has an inclined surface that gradually increases in diameter from the inner peripheral surface 35 side toward the other axial end surface 29, and is provided over the entire circumference of the gasket 1.

  In the present embodiment, as shown in FIGS. 3 and 4, the gasket 1 is formed in a symmetrical shape in the axial direction. That is, in the gasket 1, the first seal portion 21 and the second seal portion 22, the first chamfered portion 36, and the second chamfered portion 37 are symmetrical in the axial direction. In addition, the bent portion 16 of the composite 13 has a symmetrical shape in the axial direction.

  With such a configuration, when the gasket 1 is attached to the end of the first pipe 3, it becomes easy to exhibit high sealing performance regardless of the orientation of the gasket 1. Therefore, when attaching to the first pipe 3 and the second pipe 4, it is not necessary to consider the orientation of the gasket 1, so workability can be improved.

  Next, a method for manufacturing the gasket 1 will be described.

  The manufacturing method of the gasket 1 includes a material preparation process, a complex forming process, a complex flattening process, a cylindrical body forming process, and a compression molding process. And a process is advanced in this order.

  In the material preparation step, a metal mesh material 41 and an expanded graphite tape 42 as shown in FIG. 5 are prepared. The metal mesh material 41 forms the metal mesh material 11 of the gasket 1 after manufacture, and the expanded graphite tape 42 forms the expanded graphite 12 of the gasket 1.

  The metal mesh material 41 is formed by knitting metal wires 43 by a predetermined knitting method such as knit knitting. In the present embodiment, the metal mesh material 41 is formed in a horizontally long cylindrical shape whose longitudinal direction is the axial direction (longitudinal direction).

  As the metal wire 43, a metal wire having a predetermined wire diameter (thickness) is employed. For example, the metal wire 43 is a stainless steel wire having a diameter of about 0.1 to 0.3 mm (preferably 0.15 mm).

  The expanded graphite tape 42 has a width dimension comparable to the width dimension of the metal mesh material 41 in the longitudinal direction. The expanded graphite tape 42 also has a predetermined width dimension in the short direction and a predetermined thickness dimension in the thickness direction so that the expanded graphite tape 42 can be inserted into the cylindrical metal mesh material 41. .

  Here, the expanded graphite as the material to be prepared in the material preparation step is expanded graphite (expanded graphite tape) formed in a tape shape as shown in FIG. 5, but instead of this, it is a strip or wire. It may be expanded graphite cut into a shape (narrow width), or may be granular expanded graphite.

  In the composite forming step, as shown in FIG. 5, the expanded graphite tape 42 is formed so that a long strip-shaped composite 13 in which the expanded graphite tape 42 is surrounded by the metal mesh material 41 is formed. The metal mesh material 41 is disposed around.

  In the complex flattening step, the complex 13 is formed flat. As a result, the composite 13 is made into a flat long rectangular shape in which the metal wire 43 of the metal mesh material 41 is stuck to the surface of the expanded graphite tape 42.

  In the tubular body forming step, as shown in FIG. 6, the composite body 13 is formed so that a spirally wound tubular body 46 in a multiple winding state in which the short side direction of the composite body 13 is the axial direction is formed. Wound in a spiral. The number of windings at this time is appropriately set according to the required thickness for the gasket 1 to be manufactured.

  In the compression molding step, the spiral wound cylindrical body 46 is compression molded in the axial direction. For example, as shown in FIG. 7, the composite 13 is folded in the axial direction using a fixed mold 51 corresponding to the shape of the gasket 1 and a movable mold 52 that can be moved forward and backward with respect to the fixed mold 51. The compression molding process is performed as described above.

  That is, first, the spirally wound tubular body 46 is installed between the inner fixed mold 53 and the outer fixed mold 54 while being externally fitted to the inner fixed mold 53 in the fixed mold 51. Then, the movable mold 52 is moved in the direction of the arrow 56 and pushed between the inner fixed mold 53 and the outer fixed mold 54. Thus, the spirally wound tubular body 46 is compression-molded in the axial direction and the radial direction.

  By the completion of the compression molding step, the gasket 1 including the first seal portion 21 and the second seal portion 22 can be obtained. Then, in the obtained gasket 1, the composite 13 exists in the form of being folded in the axial direction so as to have the bent portion 16 as described above.

DESCRIPTION OF SYMBOLS 1 Gasket 11 Metal mesh material 12 Expanded graphite 13 Composite 16 Bending part 21 1st seal part 22 2nd seal part 23 1st seal surface 28 2nd seal surface 31 1st protrusion part 32 2nd protrusion part

Claims (2)

A gasket formed by compression molding into a cylindrical shape after a strip-shaped composite having a metal mesh material and expanded graphite surrounded by the metal mesh material is spirally wound,
A first seal portion disposed at one axial end portion and a second seal portion disposed at the other axial end portion;
The composite in the bent state has a cross-sectional shape overlapping in the radial direction,
At least one of the composites includes a bent portion that is bent at an acute angle in the radial direction.   The first seal portion has a first seal surface that tapers toward the one axial end side, and the second seal portion tapers toward the other axial end side. The gasket according to claim 1, wherein the cross-sectional shape is formed by performing compression molding of the composite so as to have.

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