Sealing gasket

Abstract

A sealing gasket (20) for a vacuum pump includes a first sealing member (22) defining a closed shape (preferably a rounded square or a rounded rectangle) and including a first surface (30), a second surface (32) opposite the first surface (30), a first inner surface (34) and a first outer surface (36) opposite the first inner surface (34), the first inner surface (34) and the first outer surface (36) are disposed between the first surface (30) and the second surface (32); a second sealing member defining a closed shape (preferably a rounded square or a rounded rectangle) and comprising a third surface (40), a fourth surface (42) opposite the third surface (40), a second inner surface (44) and a second outer surface (46) opposite the second inner surface (44), the second inner surface (44) and the second outer surface (46) are disposed between the third surface (40) and the fourth surface (42); a first longitudinal sealing member (26) connected between the first outer surface (36) and the second outer surface (46); and a second longitudinal sealing member (28) connected between the first outer surface (36) and the second outer surface (46).

Description

Technical Field

[0001] The field of the invention relates to a sealing gasket for a vacuum pump and a vacuum pump. Background Art

[0002] Rotating machines such as compressors or pumps require careful design and manufacture so that the moving parts can accurately cooperate with each other. Providing effective seals to seal the machine tends to be problematic, particularly when pressure differentials between the machine and the surrounding environment promote fluid flow (such as in a vacuum pump). It would be desirable to provide an improved seal. Summary of the invention

[0003] In one aspect, a sealing gasket for a vacuum pump is provided. The sealing gasket includes: a first sealing member, the first sealing member defines a closed shape (e.g., annular, such as a ring or a rounded square) and includes: a first surface, a second surface opposite to the first surface, a first inner surface (which may be a radial inner surface) and a first outer surface opposite to the first inner surface (which may be a radial outer surface), wherein the first inner surface and the first outer surface are arranged between the first surface and the second surface; a second sealing member, the second sealing member defines a closed shape and includes: a third surface, a fourth surface opposite to the third surface, a second inner surface (which may be a radial inner surface) and a second outer surface opposite to the second inner surface (which may be a radial outer surface), wherein the second inner surface and the second outer surface are arranged between the third surface and the fourth surface; a first longitudinal sealing member connected between the first outer surface and the second outer surface; and a second longitudinal sealing member connected between the first outer surface and the second outer surface.

[0004] The sealing gasket may also include one or more arcuate surface portions and / or one or more planar surface portions, which are arranged between one or more of the first or second sealing members and one or more of the longitudinal sealing members, and each of the one or more arcuate surface portions and / or the one or more planar surface portions is positioned at the interface between one or more of the first or second sealing members and one or more of the longitudinal sealing members.

[0005] The sealing gasket may also include one or more arcuate surface portions and / or one or more planar surface portions, which are arranged between one or more of the outer surfaces and one or more of the longitudinal sealing members and are positioned at the interface between one or more outer surfaces and one or more longitudinal sealing members.

[0006] The sealing gasket may further include a continuous arcuate surface portion at an interface between the outer surface and the longitudinal sealing member connected thereto, the continuous arcuate surface portion being arranged to provide a smooth continuous transition between the outer surface and the longitudinal sealing member connected thereto.

[0007] The sealing gasket may further include an arcuate surface portion and a discontinuity at an interface between the outer surface and the longitudinal sealing member connected thereto, the arcuate surface portion and the discontinuity being disposed between the outer surface and the longitudinal sealing member connected thereto.

[0008] The sealing gasket may also include one or more discrete planar surface portions at the interface between the outer surface and the longitudinal sealing member connected thereto, the one or more discrete planar surface portions being disposed between the outer surface and the longitudinal sealing member connected thereto. In some aspects, only one discrete planar surface portion (e.g., a chamfer) may be disposed between the outer surface and the longitudinal sealing member connected thereto. In some aspects, multiple discrete planar surface portions (i.e., multi-faceted portions) may be disposed between the outer surface and the longitudinal sealing member connected thereto.

[0009] In another aspect, a sealing gasket for a vacuum pump is provided. The sealing gasket includes: a first sealing member defining a closed shape; a second sealing member defining a closed shape; a first longitudinal sealing member connected between the first sealing member and the second sealing member; a second longitudinal sealing member connected between the first sealing member and the sealing member; and one or more arcuate surface portions and / or one or more planar surface portions, which are disposed between one or more of the sealing members and one or more of the longitudinal sealing members, and are positioned at one or more interfaces between the one or more sealing members and the one or more longitudinal sealing members.

[0010] The seal may include a continuous arcuate surface portion at the interface between the first or second sealing member and the longitudinal sealing member connected thereto, the continuous arcuate surface portion being arranged to provide a smooth continuous transition between the first or second sealing member and the longitudinal sealing member connected thereto.

[0011] In any of the foregoing aspects, the sealing gasket may be a one-piece gasket. The sealing gasket may be a molded gasket. Some or all of the sealing gaskets may have a square or rectangular cross-section. The sealing gasket may be deformable. The sealing gasket may be made of or include an elastomer.

[0012] In any of the foregoing aspects, the closed shape may be, for example, a ring, a loop, a ring or a rounded square (ie a square with rounded corners, such as a substantially square circle) or a rounded rectangle.

[0013] In any of the foregoing aspects, the first sealing member may define a rounded square, i.e. a square with rounded corners, such as a substantially square circle. The first surface may be a surface in the shape of a rounded square. The second surface may be a surface in the shape of a rounded square. The first sealing member may include a first arc segment, a second arc segment, a third arc segment, a fourth arc segment, a first substantially straight segment disposed between the first arc segment and the second arc segment, a second substantially straight segment disposed between the second arc segment and the third arc segment, a third substantially straight segment disposed between the third arc segment and the fourth arc segment, and a fourth substantially straight segment disposed between the fourth arc segment and the first arc segment. The first longitudinal sealing member may be connected to the first arc segment. The second longitudinal sealing member may be connected to the third arc segment.

[0014] In any of the foregoing aspects, the second sealing member may define a rounded square, i.e. a square with rounded corners, such as a substantially square circle. The third surface may be a surface in the shape of a rounded square. The fourth surface may be a surface in the shape of a rounded square. The second sealing member may include a fifth arc segment, a sixth arc segment, a seventh arc segment, an eighth arc segment, a fifth substantially straight segment disposed between the fifth arc segment and the sixth arc segment, a sixth substantially straight segment disposed between the sixth arc segment and the seventh arc segment, a seventh substantially straight segment disposed between the seventh arc segment and the eighth arc segment, and an eighth substantially straight segment disposed between the eighth arc segment and the fifth arc segment. The first longitudinal sealing member may be connected to the fifth arc segment. The second longitudinal sealing member may be connected to the seventh arc segment.

[0015] In any of the above aspects, the first sealing member may be an annular sealing member. In any of the above aspects, the first surface may be an annular surface. In any of the above aspects, the second surface may be an annular surface.

[0016] In any of the above aspects, the second sealing member may be an annular sealing member. In any of the above aspects, the third surface may be an annular surface. In any of the above aspects, the fourth surface may be an annular surface.

[0017] In another aspect, there is provided a vacuum pump comprising: a housing stator defining at least one pumping chamber; an end piece mountable at either end of the housing stator; and a sealing gasket as described in any preceding aspect.

[0018] A sealing gasket may be disposed in one or more sealing grooves formed in one or more of the housing stators and / or in one or more of the end pieces.

[0019] The first sealing member may be disposed in a first sealing groove. The first sealing groove may define a closed shape selected from a closed shape group consisting of a ring, a circle, an oval, an ellipse, a stadium, a rounded square, a rounded rectangle, a rounded polygon, and a square circle. The first sealing groove may be defined in an end portion of the housing stator and / or in an end member. The first arc segment may be disposed in a first substantially straight portion of the first sealing groove. The second arc segment may be disposed in a second substantially straight portion of the first sealing groove. The third arc segment may be disposed in a third substantially straight portion of the first sealing groove. The fourth arc segment may be disposed in a fourth substantially straight portion of the first sealing groove. The first substantially straight segment may be disposed in a first arc segment of the first sealing groove. The second substantially straight segment may be disposed in a second arc segment of the first sealing groove. The third substantially straight segment may be disposed in a third arc segment of the first sealing groove. The fourth substantially straight segment may be disposed in a fourth arc segment of the first sealing groove.

[0020] The second sealing member may be disposed in a second sealing groove. The second sealing groove may define a closed shape selected from a closed shape group consisting of a ring, a circle, an oval, an ellipse, a stadium, a rounded square, a rounded rectangle, a rounded polygon, and a square circle. The second sealing groove may be defined in an end portion of the housing stator and / or in an end member. The fifth arc segment may be disposed in a first substantially straight portion of the second sealing groove. The sixth arc segment may be disposed in a second substantially straight portion of the second sealing groove. The seventh arc segment may be disposed in a third substantially straight portion of the second sealing groove. The eighth arc segment may be disposed in a fourth substantially straight portion of the second sealing groove. The fifth substantially straight segment may be disposed in a first arc segment of the second sealing groove. The sixth substantially straight segment may be disposed in a second arc segment of the second sealing groove. The seventh substantially straight segment may be disposed in a third arc segment of the second sealing groove. The eighth substantially straight segment may be disposed in a fourth arc segment of the second sealing groove.

[0021] In another aspect, a housing stator for a vacuum pump is provided. The housing stator comprises: a first sealing groove arranged along a joining surface of the housing stator, the joining surface being used to receive another housing stator, thereby defining at least one pumping chamber; and a second sealing groove arranged in an end surface of the housing stator, the end surface being used to receive an end component; wherein the first and second sealing grooves are connected at an edge of the housing stator via a transition groove portion, the transition groove portion comprising one or more arcuate surface portions and / or one or more planar surface portions.

[0022] The first and second sealing grooves may be connected at an edge of the housing stator via a multi-faceted transition groove portion including a plurality of planar surface portions.

[0023] The first and second sealing grooves may be connected at an edge of the housing stator via a chamfered transition groove portion including only a single planar surface portion.

[0024] The first and second sealing grooves may be connected at an edge of the housing stator via a continuous transition groove portion including only a continuous arcuate surface portion.

[0025] The first and second sealing grooves may be connected at an edge of the housing stator via a transition groove portion including an arcuate surface portion and a discontinuity. The discontinuity may be provided between the arcuate surface portion and either the first or second sealing groove.

[0026] The first and second sealing grooves may be connected at an edge of the housing stator via a transition groove portion including an arcuate surface portion and a planar surface portion. The planar surface portion may be disposed between the arcuate surface portion and either the first or second sealing groove.

[0027] The first and second sealing grooves may be connected at an edge of the housing stator via a transition groove portion including an arcuate surface portion and two planar surface portions. Each planar surface portion may be disposed between the arcuate surface portion and a corresponding one of the first and second sealing grooves.

[0028] In another aspect, a housing stator for a vacuum pump is provided. The housing stator comprises: a connecting surface of the housing stator, the connecting surface being used to receive another housing stator, thereby defining at least one pumping chamber; a sealing groove provided in an end surface of the housing stator, the end surface being used to receive an end component; and a transition groove portion provided between the connecting surface and the sealing groove at an edge of the housing stator, the transition groove portion comprising one or more arcuate surface portions and / or one or more planar surface portions.

[0029] The transition groove portion may be a multi-faceted transition groove portion including a plurality of planar surface portions.

[0030] The transition groove portion may be a chamfered transition groove portion including only a single planar surface portion.

[0031] The transition groove portion may be a continuous transition groove portion including only a continuous arcuate surface portion.

[0032] The transition groove portion may include an arcuate surface portion and a discontinuity. The discontinuity may be disposed between the arcuate surface portion and either the sealing groove or the joining surface.

[0033] The transition groove portion may include an arcuate surface portion and a planar surface portion. The planar surface portion may be disposed between the arcuate surface portion and either the sealing groove or the joining surface.

[0034] The transition groove portion may include an arcuate surface portion and two planar surface portions. Each planar surface portion may be disposed between the arcuate surface portion and a corresponding one of the sealing groove and the joining surface.

[0035] In another aspect, a vacuum pump is provided, comprising: a housing stator defining at least one pumping chamber; an end piece capable of being mounted at either end of the housing stator; and a sealing gasket disposed between the housing stator and the end piece. One or more of the housing stators are housing stators according to any of the preceding aspects. For example, both of the housing stators may be according to one (e.g., different) of the preceding aspects. The sealing gasket may be according to any of the preceding aspects. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0037] Figure 1 is a schematic diagram (not to scale) showing a housing of a vacuum pump;

[0038] Figure 2 is a schematic diagram of a sealing gasket (not to scale);

[0039] Figure 3 is another schematic diagram of a sealing gasket (not to scale);

[0040] Figure 4 is a process flow diagram illustrating certain steps of a method of incorporating a sealing gasket into a housing;

[0041] Figure 5 is a schematic diagram (not to scale) showing a sealing gasket incorporated into a housing;

[0042] Figure 6a -c is a schematic diagram (not to scale) showing further details of the sealing gasket incorporated into the housing near the T-joint;

[0043] Figure 7a and 7b is a schematic diagram (not to scale) showing a portion of an alternative housing stator for the housing;

[0044] Figure 8a and 8b is a schematic diagram (not to scale) showing a portion of an alternative housing stator for the housing;

[0045] Figure 9a and 9b is a schematic diagram (not to scale) showing a portion of an alternative housing stator for the housing;

[0046] Fig.10a and 10b is a schematic diagram (not to scale) showing a portion of an alternative housing stator for the housing;

[0047] Fig.11a and 11b is a schematic diagram (not to scale) showing a portion of an alternative housing stator for the housing;

[0048] Fig.12a and 12b is a schematic diagram (not to scale) showing a portion of an alternative housing stator for the housing;

[0049] Fig.13 is a schematic diagram (not to scale) showing an alternative mold cavity for a sealing gasket;

[0050] Fig.14 is a schematic diagram (not to scale) showing an alternative mold cavity for a sealing gasket;

[0051] Fig.15 is a schematic top view of another sealing gasket (not to scale);

[0052] Fig.16 is a perspective schematic view (not to scale) of the other sealing liner; and

[0053] Fig.17 is a schematic diagram (not to scale) showing a portion of the further sealing gasket which is disposed in a sealing groove formed in a housing stator of a casing. DETAILED DESCRIPTION

[0054] According to one embodiment, Figure 11 is a schematic diagram (not to scale) showing a housing 10 of a vacuum pump. The housing 10 includes a pair of housing stators 12, 14 and a pair of end plates 16, 18. The housing stators 12, 14 define recesses that receive components of the vacuum pump. The housing stators 12, 14 are brought together to hold the components in those recesses. The end plates 16, 18 are then used to hold the housing stators 12, 14. This provides a particularly convenient assembly of the vacuum pump.

[0055] In other words, the housing 10 of the vacuum pump may be formed of a plurality of parts, including the casings 12, 14 and the end plates 16, 18, which need to be sealed during assembly. Figure 1 In the arrangement shown in FIG. 1 , the stator is formed by bringing two housing parts or shells 12 , 14 together and then retaining the housing parts or shells 12 , 14 between the pair of end plates 16 , 18 .

[0056] As will be explained in more detail below, in this embodiment, in order to adequately seal the housing stators 12, 14 together, one or more (e.g., two) longitudinal seals are positioned along the joining surfaces of the housing stators 12, 14. Also, in order to ensure adequate sealing between the housing stators 12, 14 and the respective end plates 16, 18, a pair of annular seals are positioned between the end plates 16, 18 and the housing stators 12, 14.

[0057] According to one embodiment, Figure 2 is a schematic diagram (not to scale) of a sealing gasket used to seal the housing 10 .

[0058] The sealing gasket 20 includes a first generally annular sealing member 22 , a second generally annular sealing member 24 , a first longitudinal sealing member 26 , and a second longitudinal sealing member 28 .

[0059] The first annular sealing member 22 includes a first annular surface 30, a second annular surface 32 opposite the first annular surface 30, a first radially inner surface 34, and a first radially outer surface 36 opposite the first radially inner surface 34. The first radially inner surface 34 and the first radially outer surface 36 are disposed between the first annular surface 30 and the second annular surface 32.

[0060] The second annular sealing member 24 includes a third annular surface 40, a fourth annular surface 42 opposite the third annular surface 40, a second radially inner surface 44, and a second radially outer surface 46 opposite the second radially inner surface 44. The second radially inner surface 44 and the second radially outer surface 46 are disposed between the third annular surface 40 and the fourth annular surface 42.

[0061] The first longitudinal seal member 26 is connected or attached between the first radially outer surface 36 (of the first annular seal member 22 ) and the second radially outer surface 46 (of the second annular seal member 24 ).

[0062] The second longitudinal seal member 28 is connected or attached between the first radially outer surface 36 (of the first annular seal member 22 ) and the second radially outer surface 46 (of the second annular seal member 24 ).

[0063] The second longitudinal sealing member 28 is arranged opposite to the first longitudinal sealing member 26. That is, the second longitudinal sealing member 28 is connected to the first and second annular sealing members 22, 24 and is on a side of the first and second annular sealing members 22, 24 opposite to the side on which the first longitudinal sealing member 26 is connected to the first and second annular sealing members 22, 24.

[0064] The first annular sealing member 22 is an annular sealing member having a square or rectangular cross section.

[0065] The second annular sealing member 24 is an annular sealing member and has a square or rectangular cross section.

[0066] The first longitudinal sealing member 26 may be an O-ring cord. The first longitudinal sealing member 26 has a square or rectangular cross-section.

[0067] The second longitudinal sealing member 28 may be an O-ring rope. The second longitudinal sealing member 28 has a square or rectangular cross-section.

[0068] In this embodiment, the sealing gasket 20 is a continuous, one-piece sealing gasket.

[0069] In this embodiment, the sealing gasket includes arcuate surface portions 48a-d at the interface between the annular sealing members 22, 24 and the longitudinal sealing members 26, 28. In particular, at the interface between the first annular sealing member 22 and the first longitudinal sealing member 26, there is an arcuate surface portion 48a between the first radially outer surface 36 and the first longitudinal sealing member 26. And, at the interface between the first annular sealing member 22 and the second longitudinal sealing member 28, there is an arcuate surface portion 48b between the first radially outer surface 36 and the second longitudinal sealing member 28. And, at the interface between the second annular sealing member 24 and the first longitudinal sealing member 26, there is an arcuate surface portion 48c between the second radially outer surface 46 and the first longitudinal sealing member 26. And, at the interface between the second annular sealing member 24 and the second longitudinal sealing member 28, there is an arcuate surface portion 48d between the second radially outer surface 46 and the second longitudinal sealing member 28.

[0070] In this embodiment, the arcuate surface portions 48a-d tend to make the radially outer surfaces 36, 46 of the annular seal members 22, 24 continuous with the surfaces of the longitudinal seal members 26, 28. There is a smooth, continuous transition between the radially outer surfaces 36, 46 of the annular seal members 22, 24 and the longitudinal seal members 26, 28. The arcuate surface portions 48a-d smooth the transition between the radially outer surfaces 36, 46 of the annular seal members 22, 24 and the longitudinal seal members 26, 28 and further provide a continuous transition therebetween.

[0071] The sealing gasket 20 is made of a deformable or flexible material, such as an elastomeric material (e.g., fluoroelastomer (FKM / FPM) or perfluoroelastomer (FFKM)) or silicon, so that the sealing gasket 20 is deformable or flexible. Therefore, the sealing gasket 20 can be deformed into a desired shape or configuration suitable for use as a seal for the housing 10.

[0072] Figure 3 is a schematic diagram (not to scale) showing the sealing gasket 20 which has been deformed into a configuration suitable for sealing the housing 10 .

[0073] In this configuration, the annular sealing members 22, 24 are square annular members with arcuate corners. The configuration has major faces (which are the first radial inner surface 34 and the first radial outer surface 36 of the first annular sealing member 22 and the second radial inner surface 44 and the second radial outer surface 46 of the second annular sealing member 24), which, in use, abut the major faces of the end plates 16, 18 and the adjacent faces of the housing stators 12, 14. In this example, the annular sealing members 22, 24 have substantially planar axial outer faces, which are provided by the first radial inner surface 34 and the second radial inner surface 44, respectively. The annular sealing members 22, 24 have substantially planar axial inner faces, which are provided by the first radial outer surface 36 and the second radial outer surface 46, respectively. The longitudinal sealing member 26 is connected between the facing axial inner faces of the annular sealing members 22, 24 (i.e., between the first radial outer surface 36 and the second radial outer surface 46). The annular sealing members 22, 24 have substantially constant thickness.

[0074] Figure 4 is a process flow diagram illustrating certain steps (s40-s48) of a method of fitting, installing or incorporating a sealing gasket 20 into a housing 10.

[0075] Figure 5 Schematic diagram (not to scale) showing the incorporation of the sealing gasket 20 into the housing 10 to facilitate understanding Figure 4 process.

[0076] At step s40 , a housing stator 14 is provided into which components of a vacuum pump (not shown) may be assembled.

[0077] At step s42, the sealing gasket 20 is positioned relative to the housing stator 14 so that the first and second longitudinal sealing members 26, 28 are positioned along the joint surface of the housing stator 14, typically in sealing grooves extending along the joint surface of the housing stator 14. This may be as shown in FIG. Figure 5 Described in.

[0078] At step s44 , the housing stator 12 is brought into close contact with the longitudinal sealing members 26 , 28 .

[0079] Reference Figure 5 , the housing stator 12 can be moved toward the connecting surface of the housing stator 14 onto the longitudinal sealing members 26, 28, such as Figure 5 Indicated by arrow and reference numeral 50.

[0080] At step s46, the housing stators 12, 14 are clamped together, which causes the longitudinal sealing members 26, 28 to compress.

[0081] Therefore, after step s46, the annular sealing members 22, 24 tend to extend or protrude axially from the axial ends of the housing stators 12, 14 that are assembled together.

[0082] At step s48, the end plates 16, 18 are brought together so that the annular seals 26, 28 are compressed in the axial (ie longitudinal) direction.

[0083] The annular sealing members 22 , 24 may be positioned in annular sealing grooves positioned in the housing stators 12 , 14 and / or the end plates 16 , 18 .

[0084] Reference Figure 5 , the end plate 18 is shown to have been moved to the first annular sealing member 22 at the first end of the assembled housing stators 12, 14. The end plate 16 can be moved to the second annular sealing member 24 at the second end (opposite to the first end) of the assembled housing stators 12, 14, as shown. Figure 5 Indicated by arrow and reference numeral 52.

[0085] Thus, a method of fitting, installing or incorporating a sealing gasket 20 into a housing 10 is provided.

[0086] Vacuum pumps having an axial split along the stator typically require seals at each end of the split, known as a T-junction. Embodiments provide a sealing gasket, such as a one-piece elastomeric gasket, for providing a T-junction sealing arrangement for a metal, plated, or coated clam pump.

[0087] Figure 6a -c is a schematic diagram (not to scale) showing further details of the sealing gasket 20 incorporated into the housing 10 in the vicinity of the T-junction. Figure 6a Only one of the T-joints is depicted in FIG. 1-c, but a person skilled in the art will appreciate that corresponding or similar features may be present at the location of the other T-joints of the assembly and in the other housing stator 12.

[0088] In particular, Figure 6a A sealing gasket 20 is shown incorporated into the housing 10 adjacent the T-joint. Figure 6b The T-junction vicinity (i.e. Figure 6a The same area of ​​the housing stator 14 is omitted with the sealing gasket 20 . Figure 6c Shows Figure 6b 1 is a side cross-sectional view of the portion of the housing stator 14 shown in FIG.

[0089] In this embodiment, the housing stator 14 includes a first sealing groove 60 extending along the (upper) joining surface of the housing stator 14 and a second sealing groove 62 extending across the end surface of the housing stator 14 .

[0090] In this embodiment, the sealing gasket 20 is arranged so that the longitudinal sealing member (in this case, the first longitudinal sealing member 26) is positioned in the first sealing groove 60, and so that the annular sealing member (in this case, the second annular sealing member 24) is positioned in the second sealing groove 62.

[0091] like Figure 6b and 6c As shown in FIG. 1 , in this embodiment, the housing stator 14 includes an arcuate surface portion 64 at the interface between the first sealing groove 60 and the second sealing groove 62. The arcuate surface portion 64 of this embodiment can be regarded as a transition groove portion between the first sealing groove 60 and the second sealing groove 62.

[0092] In this embodiment, the arcuate surface portion 64 tends to make the concave surfaces (eg, flat bottoms) of the sealing grooves 60, 62 continuous with each other. There is a smooth, continuous transition between the first and second sealing grooves 60, 62. The arcuate surface portion 64 provides a smooth, continuous transition between the sealing grooves 60, 62.

[0093] Preferably, the arcuate surface portion 64 between the sealing grooves 60, 62 is complementary to or coincides with the corresponding arcuate surface portions 48a-d of the sealing gasket 20. This tends to provide improved contact between the sealing gasket and the housing 10, and therefore provides an improved seal.

[0094] Advantageously, the rounded or arcuate edge / surface 64 between the gasket groove (i.e., the first seal groove 60) and the annular seal groove (i.e., the second seal groove 62) tends to allow the sealing gasket to deform or flow around the edge without losing reliable contact with the sealing surface. The arrangement tends to withstand all compression conditions. In addition, the arcuate surfaces 64, 48a-d tend to eliminate sharp edges and create a single continuous tool path for the gasket and the annular seal groove. The sealing gasket 20 tends to be self-aligning regardless of the depth of the groove.

[0095] The sealing gasket is intended to be easily installed into the housing or vacuum pump.

[0096] Advantageously, the sealing gaskets described herein tend to be relatively easy to produce or manufacture compared to conventional sealing assemblies. For example, the sealing gaskets tend to be relatively easy to produce via molding. For example, the sealing gaskets can be molded in a mold as a one-piece, substantially planar or flat article (e.g., Figure 2 and previously described in more detail above), and then deformed or manipulated into a desired shape or configuration (e.g., as Figure 3 and described in more detail previously above). Molding can be performed using a mold tool that includes a first portion that includes a recess that is the desired shape of the sealing gasket; a substantially planar second portion can be placed over the recess in the first portion to define a mold cavity in which the sealing gasket can be formed. Advantageously, a sealing gasket formed in this manner tends to have no parting line (where two different sides of the mold meet). Therefore, the likelihood of the sealing gasket separating tends to be greatly reduced. In addition, any mold flash that appears on the molded sealing gasket tends to be confined to non-critical areas of the sealing gasket, such as when Figure 2 When the sealing liner is oriented in the direction of the upper surface, it extends outwardly from the upper surface of the sealing liner. This tends to improve the durability and stability of the sealing liner.

[0097] Conventionally, when the compression of the gasket and the annular seal is unbalanced, the T-joint sealing surfaces may separate. Such separation may result in leakage and may occur during assembly or due to thermal expansion of the seal. Also conventionally, sharp edges on the ends of the gasket grooves are difficult to manufacture and may cut the annular seal, resulting in leakage. Also, conventional complex gasket profiles of current designs may have irregular deformations that may result in leakage. The methods and apparatus described above advantageously tend to address these problems.

[0098] Advantageously, the substantially constant or uniform cross-section of the sealing gasket described above tends to result in reduced deformation, thereby making the T-seal more resistant to a wide range of compression and reducing leakage.

[0099] The sealing gaskets described above tend to facilitate the use of T-seals for higher temperatures, for example up to 300°C.

[0100] The sealing gasket can be designed to be slightly shorter than the longitudinal slot (ie the gasket slot) in the housing stator so that it has lower tension during assembly. This tends to make the sealing gasket self-locating regardless of the depth of the annular groove.

[0101] The width / thickness of the sealing liner can be constant in the T-seal area, which tends to result in reduced deformation. This tends to make the T-seal more tolerant of a wide compression range, which reduces leakage. The width / thickness of the sealing liner can also be a constant width throughout the entire sealing liner.

[0102] Advantageously, the seal can be formed in a manner such that the sides of the seal are in one plane (i.e. Figure 2 The sealing gasket is molded in a (in a) configuration. This tends to obtain a continuous sealing surface from the side wall of the mold tool without any parting lines, which ensures high integrity of the sealing surface. The shape of such a one-piece seal tends to be reconfigurable to fit the sealing housing using only bending and without the need to twist any section of the seal.

[0103] It will be appreciated that the cord and pad may have different shapes or thicknesses to suit the arrangement of the housing.

[0104] In the above embodiments, the sealing gasket is a continuous one-piece sealing gasket. However, in other embodiments, the sealing gasket includes a plurality of separate parts that are joined together. The plurality of parts can be joined together by any joining means or methods, such as using an adhesive, fusing or via an interference fit.

[0105] In the above embodiments, the sealing gasket has a substantially constant cross-section over its portion. However, in other embodiments, the sealing gasket has a non-constant cross-section.

[0106] In the above embodiments, the sealing gaskets have a square or rectangular cross-section. However, in other embodiments, some or all of the sealing gaskets have an alternative cross-section other than square or rectangular, such as circular, triangular, oval, etc.

[0107] In the above embodiments, the sealing gasket may be made of an elastomer. In some embodiments, the sealing gasket may be made of a different, deformable material, such as metal.

[0108] Although the major faces of the sealing gaskets in the above embodiments are substantially planar, it will be appreciated that they may be of any shape suitable for engagement with the major faces of the end plates and the adjacent faces of the housing stator.

[0109] In the above embodiments, the sealing gasket includes an arcuate surface portion at the interface between the annular sealing member and the longitudinal sealing member. These arcuate surface portions provide a continuous transition between the annular sealing member and the longitudinal sealing member. Similarly, one or both of the housing stators include an arcuate surface portion between the longitudinal gasket sealing groove and the annular sealing groove. However, in other embodiments, the interface between the annular sealing member and the longitudinal sealing member and / or the interface between the stator sealing grooves in the stator parts is not arcuate and / or is not continuous.

[0110] As a first example, Figure 7a and 7b A housing stator 12 , 14 is shown according to an alternative embodiment.

[0111] In this embodiment, the housing stator 14 includes an arcuate surface portion 70 at the interface between the first seal groove 60 and the second seal groove 62. The arcuate surface portion 70 provides a degree of continuity between the concave surfaces (eg, flat bottoms) of the seal grooves 60,62.

[0112] And in this embodiment, the housing stator 12 includes a sealing groove 72 at its end surface for receiving an annular sealing member. When the housing stators 12, 14 are assembled together, the sealing grooves 62 and 72 form an annular sealing groove for receiving the annular sealing members 22, 24 of the sealing gasket 20. The sealing groove 72 includes an arcuate surface portion 74 at the interface between the sealing groove 72 and the connecting surface of the housing stator 12 (i.e., the surface of the housing stator 12 connected to the housing stator 14 / the surface facing the housing stator 14). In addition, a discontinuity or edge 76 is provided between the arcuate surface portion 74 and the connecting surface of the housing stator 12. Such a discontinuity or edge 76 tends to facilitate or enable the omission of a sealing groove in the connecting surface of the housing stator 12. Therefore, it tends to facilitate the manufacture of the housing stator 12.

[0113] The discontinuity or edge 76 tends to provide improved contact between the sealing gasket 20 and the housing 10 and, therefore, provides an improved seal.

[0114] As a second example, Figure 8a and Figure 8b The housing stators 12 and 14 are shown according to another alternative embodiment.

[0115] In this embodiment, the housing stator 14 includes a multi-faceted portion 80 at the interface between the first seal groove 60 and the second seal groove 62. In this embodiment, a plurality of discrete surfaces are provided between the first seal groove 60 and the second seal groove 62. Thus, the first and second seal grooves 60, 62 are distinct from each other and are discrete rather than continuous. Although in this example, the multi-faceted portion 80 includes three distinct surfaces, those skilled in the art will appreciate that the multi-faceted portion 80 may include a different number of facets or surfaces, such as more or less than three.

[0116] Such a faceted portion 80 tends to be relatively easy to manufacture, for example by machining.

[0117] Equivalent faceted portions may be provided in the opposing housing stator 12 .

[0118] As a third example, Figure 9a and 9b A housing stator 12 , 14 according to yet another alternative embodiment is shown.

[0119] In this embodiment, the housing stator 14 includes only a single planar surface portion 90 at the interface between the first seal groove 60 and the second seal groove 62. The single planar surface portion 90 can be considered a chamfer or chamfer transition between the first seal groove 60 and the second seal groove 62. The first and second seal grooves 60, 62 are distinct from each other and are discrete rather than continuous.

[0120] Such a single planar surface portion 90 tends to be relatively easy to manufacture, for example by machining.

[0121] An identical single planar surface portion may be provided in the opposing housing stator 12 .

[0122] As a fourth example, Fig.10a and Fig.10b A housing stator 12 , 14 is shown according to another alternative embodiment.

[0123] In this embodiment, the housing stator 14 includes a multi-faceted portion 100 at the interface between the first sealing groove 60 and the second sealing groove 62. In this embodiment, a plurality of discrete surfaces are provided between the first sealing groove 60 and the second sealing groove 62. Thus, the first and second sealing grooves 60, 62 are distinguished from each other and are discrete rather than continuous. Although in this example, the multi-faceted portion 100 includes four distinct surfaces, it will be appreciated by those skilled in the art that the multi-faceted portion 100 may include a different number of facets or surfaces, such as more or less than four. By having more facets, the multi-faceted portion 100 may approximate an arcuate surface while being easier to manufacture.

[0124] Such a faceted portion 80 tends to be relatively easy to manufacture, for example by machining.

[0125] Equivalent faceted portions may be provided in the opposing housing stator 12 .

[0126] As a fifth example, Fig.11a and Fig.11b A housing stator 12 , 14 is shown according to an alternative embodiment.

[0127] In this embodiment, the housing stator 14 includes an arcuate surface portion 110 and a planar surface portion 112 at the interface between the first seal groove 60 and the second seal groove 62. The arcuate surface portion 70 provides a degree of continuity between the concave surfaces (e.g., flat bottoms) of the seal grooves 60 and 62. The planar surface portion 112 is disposed between the arcuate surface portion 110 and the first seal groove 60.

[0128] And in this embodiment, the housing stator 12 may include a sealing groove for receiving an annular sealing member at its end surface. This sealing groove includes an arc surface portion 114 and a plane surface portion 116 at the interface between the sealing groove and the connecting surface of the housing stator 12. The plane surface portion 116 is provided between the arc surface portion 114 and the connecting surface of the housing stator 12.

[0129] The use of one or both planar surface portions 112, 116 may provide improved contact between the sealing gasket 20 and the housing 10, and therefore provide an improved seal.

[0130] As a sixth example, Fig.12a and 12b A housing stator 12 , 14 is shown according to an alternative embodiment.

[0131] In this embodiment, the housing stator 14 includes an arcuate surface portion 120 and two planar surface portions 122, 124 at the interface between the first seal groove 60 and the second seal groove 62. The arcuate surface portion 120 provides a degree of continuity between the concave surfaces (e.g., flat bottoms) of the seal grooves 60 and 62. The first planar surface portion 122 is disposed between the arcuate surface portion 120 and the first seal groove 60. The second planar surface portion 124 is disposed between the arcuate surface portion 120 and the second seal groove 62.

[0132] And in this embodiment, the housing stator 12 may include a sealing groove for receiving an annular sealing member at its end surface. This sealing groove includes an arc surface portion 126 and two plane surface portions 127, 128 at the interface between the sealing groove and the connecting surface of the housing stator 12. The plane surface portion 127 is provided between the arc surface portion 126 and the connecting surface of the housing stator 12. The plane surface portion 128 is provided between the arc surface portion 126 and the sealing groove at the end surface of the housing stator 12.

[0133] The use of one or more of the planar surface portions 122, 124, 127, 128 may provide improved contact between the sealing gasket 20 and the housing 10, and therefore provide an improved seal.

[0134] In the above embodiments, the sealing gasket may be manufactured by molding as a one-piece, substantially planar or flat article, such as Figure 2 However, in other embodiments, the sealing gasket may be manufactured in a different manner, for example, by molding as a one-piece, substantially planar or flat article, such as Fig.13 (See single-piece, substantially planar or flat liner 130) or Fig.14 (See the one-piece, substantially planar or flat pad 140).

[0135] In some embodiments, the sealing gasket comprises an annular sealing member which, in use, seals against the end plate. However, these sealing members may have shapes other than strictly annular. The sealing member defines a closed shape and may define a closed shape other than a ring, such as a ring, annular, elliptical, oval, rounded square or rounded rectangle (i.e. a square or rectangle with rounded corners), spherical or rounded polygonal.

[0136] Embodiments will now be described in which the sealing member which seals against the end plate in use defines a rounded square, ie a substantially square-shaped, shape.

[0137] Fig.15 and 16 is a schematic diagram (not to scale) of another sealing gasket 150 for sealing the housing 10 according to one embodiment.

[0138] The sealing gasket 150 includes a first sealing member 151 , a second annular sealing member 152 , a first longitudinal sealing member 153 , and a second longitudinal sealing member 154 .

[0139] The first sealing member 151 defines a closed shape. In particular, in this embodiment, the first sealing member 151 defines a rounded square, ie a square with rounded corners, or a substantially squared circle.

[0140] The first sealing member 151 includes a first rounded square surface 161, a second rounded square surface 162 opposite to the first rounded square surface 161, a first inner surface 163, and a first outer surface 164 opposite to the first inner surface 163. The first inner surface 163 and the first outer surface 164 are disposed between the first rounded square surface 161 and the second rounded square surface 162.

[0141] The first sealing member 151 includes a first arc segment 165a, a second arc segment 165b, a third arc segment 165c, a fourth arc segment 165d, a first substantially straight segment 166a disposed between the first arc segment 165a and the second arc segment 165b, a second substantially straight segment 166b disposed between the second arc segment 165b and the third arc segment 165c, a third substantially straight segment 166c disposed between the third arc segment 165c and the fourth arc segment 165d, and a fourth substantially straight segment 166d disposed between the fourth arc segment 165d and the first arc segment 165a. The first longitudinal sealing member 153 is connected to the first arc segment 165a. The second longitudinal sealing member 154 is connected to the third arc segment 165c.

[0142] The second sealing member 152 defines a closed shape. In particular, in this embodiment, the second sealing member 152 defines a rounded square, ie, a square with rounded corners, or a substantially squared circle.

[0143] The second sealing member 152 includes a third rounded square surface 171, a fourth rounded square surface 172 opposite to the third rounded square surface 171, a second inner surface 173, and a second outer surface 174 opposite to the second inner surface 173. The second inner surface 173 and the second outer surface 174 are disposed between the third rounded square surface 171 and the fourth rounded square surface 172.

[0144] The second sealing member 152 includes a fifth arc segment 175a, a sixth arc segment 175b, a seventh arc segment 175c, an eighth arc segment 175d, a fifth substantially straight segment 176a disposed between the fifth arc segment 175a and the sixth arc segment 175b, a sixth substantially straight segment 176b disposed between the sixth arc segment 175b and the seventh arc segment 175c, a seventh substantially straight segment 176c disposed between the seventh arc segment 175c and the eighth arc segment 175d, and an eighth substantially straight segment 176d disposed between the eighth arc segment 175d and the fifth arc segment 175a. The first longitudinal sealing member 153 is connected to the fifth arc segment 175a. The second longitudinal sealing member 154 is connected to the seventh arc segment 175c.

[0145] The first longitudinal sealing member 153 is connected or attached between the first outer surface 164 (of the first sealing member 151 ) and the second outer surface 174 (of the second sealing member 152 ).

[0146] The second longitudinal sealing member 154 is connected or attached between the first outer surface 164 (of the first sealing member 151 ) and the second outer surface 174 (of the second sealing member 152 ).

[0147] The second longitudinal sealing member 154 is arranged opposite to the first longitudinal sealing member 153. That is, the second longitudinal sealing member 154 is connected to the first and second sealing members 151, 152 and is on a side of the first and second sealing members 151, 152 opposite to the side on which the first longitudinal sealing member 153 is connected to the first and second sealing members 151, 152.

[0148] The first sealing member 151 has a square or rectangular cross section. The second sealing member 152 has a square or rectangular cross section.

[0149] The first longitudinal sealing member 153 may be an O-ring cord.The first longitudinal sealing member 153 may have a square or rectangular cross-section.

[0150] The second longitudinal sealing member 154 may be an O-ring cord. The second longitudinal sealing member 154 may have a square or rectangular cross-section.

[0151] In this embodiment, the sealing gasket 150 is a continuous, one-piece sealing gasket.

[0152] In this embodiment, the sealing gasket 150 includes arcuate surface portions 180a-d at the interface between the rounded square sealing members 151, 152 and the longitudinal sealing members 153, 154. These can be compared with those previously described above with reference to Figure 2 The arcuate surface portions 48a-d described in greater detail are similar or identical.

[0153] The sealing gasket 150 is made of a deformable or flexible material, such as an elastomeric material (e.g., fluoroelastomer (FKM / FPM) or perfluoroelastomer (FFKM)) or silicon, so that the sealing gasket 150 is deformable or flexible. Therefore, the sealing gasket 150 can be deformed into a desired shape or configuration suitable for use as a seal for the housing 10.

[0154] The sealing gasket 150 may be installed into the housing 10, for example as previously described above with reference to Figure 4In this way, the first and second longitudinal sealing members 153, 154 can be arranged to be sealingly engaged with the housing stators 12, 14, which can be clamped together to compress the longitudinal sealing members 153, 154. And, the rounded square sealing members 151, 152 can be positioned in a closed-shaped sealing groove located in the housing stators 12, 14 and / or the end plates 16, 18. The sealing groove can have any suitable closed shape, such as a ring, a circle, an oval, an ellipse, a stadium shape, a rounded square, a square circle, a rounded rectangle, a rounded polygon, etc.

[0155] Fig.17 1 is a schematic diagram (not to scale) showing a first sealing member 151 fitted into a closed-shaped sealing groove 177 positioned in the housing stator 12, 14. In this embodiment, the sealing groove 177 defines a rounded square or rounded rectangle. In this embodiment, the second sealing member 152 can be fitted into a substantially identical closed-shaped sealing groove 177 at the opposite end of the housing stator 12, 14.

[0156] In this embodiment, the arcuate sections 165a - d of the first sealing member 151 are positioned in corresponding substantially straight portions of the sealing groove 177 . Also, the substantially straight sections 166a - d of the first sealing member 151 are positioned in corresponding arcuate portions of the sealing groove 177 .

[0157] In particular, the first arc segment 165a is arranged in the first substantially straight portion 178a of the sealing groove 177, the second arc segment 165b is arranged in the second substantially straight portion 178b of the sealing groove 177, the third arc segment 165c is arranged in the third substantially straight portion 178c of the sealing groove 177, the fourth arc segment 165d is arranged in the fourth substantially straight portion 178d of the sealing groove 177, the first substantially straight segment 166a is arranged in the first arc portion 179a of the sealing groove 177, the second substantially straight segment 166b is arranged in the second arc portion 179b of the sealing groove 177, the third substantially straight segment 166c is arranged in the third arc portion 179c of the sealing groove 177, and the fourth substantially straight segment 166d is arranged in the fourth arc portion 179d of the sealing groove 177.

[0158] As described above, the substantially rounded square sealing member is positioned in the rounded square sealing groove so that the arcuate section of the rounded square sealing member is positioned in the substantially straight section of the sealing groove, and the substantially straight section of the sealing member is positioned in the arcuate section of the sealing groove 177. This advantageously tends to reduce stress in the rounded square sealing member. In particular, compared to sealing members of other shapes, the compound bending and / or distortion when the sealing member is installed in the sealing groove tends to be reduced. This tends to improve the life of the seal. In addition, the retention of the sealing member in the sealing groove tends to be improved. For example, the reduced distortion and / or compound bending of the sealing member tends to reduce the sealing member from twisting out of the sealing groove.

[0159] Although an illustrative embodiment of the present invention has been disclosed herein in detail with reference to the accompanying drawings, it is understood that the invention is not limited to this precise embodiment and that various changes and modifications may be made thereto by those skilled in the art without departing from the scope of the invention as defined by the appended claims and their equivalents.

[0160] List of Reference Numerals

[0161] 10- Shell

[0162] 12, 14-Casing stator

[0163] 16, 18-End plate

[0164] 20-Sealing gasket

[0165] 22-First annular sealing member

[0166] 24-Second annular sealing member

[0167] 26-First longitudinal sealing member

[0168] 28-Second longitudinal sealing member

[0169] 30-first annular surface

[0170] 32-Second annular surface

[0171] 34-first radial inner surface

[0172] 36- first radial outer surface

[0173] 40-third annular surface

[0174] 42-Fourth annular surface

[0175] 44- second radial inner surface

[0176] 46- second radial outer surface

[0177] 48a-d-arc surface portion

[0178] s40-s48-method steps

[0179] 50, 52-Direction

[0180] 60-First sealing groove

[0181] 62-Second sealing groove

[0182] 64-Curved surface part

[0183] 70-Curved surface part

[0184] 72-Seal groove

[0185] 74 – curved surface section

[0186] 76-Discontinuity

[0187] 80-Multi-faceted section

[0188] 90-plane surface section

[0189] 100-Multi-faceted section

[0190] 110-Curved surface part

[0191] 112- plane surface part

[0192] 114-Curved surface part

[0193] 116- plane surface part

[0194] 120-Curved surface part

[0195] 122, 124- plane surface part

[0196] 126-Curved surface part

[0197] 127, 128- plane surface part

[0198] 130, 140-Sealing gasket

[0199] 150-Sealing Gasket

[0200] 151-first sealing member

[0201] 152-Second sealing member

[0202] 153-first longitudinal sealing member

[0203] 154-Second longitudinal sealing member

[0204] 161-First rounded square surface

[0205] 162-Second rounded square surface

[0206] 163-first inner surface

[0207] 164-first outer surface

[0208] 165a-d-arc section

[0209] 166a-d-straight section

[0210] 171-Third rounded square surface

[0211] 172-Fourth rounded square surface

[0212] 173- Second inner surface

[0213] 174- second outer surface

[0214] 175a-d-arc section

[0215] 176a-d-straight section

[0216] 177-Seal groove

[0217] 178a-d - straight part of seal groove

[0218] 179a-d-arc section of sealing groove

[0219] 180a-d-arc surface part

Claims

1. A sealing gasket for a vacuum pump, the sealing gasket comprising: A first sealing member defining a closed shape comprises: a first surface; a second surface opposite to the first surface; a first inner surface; and a first outer surface opposite to the first inner surface, wherein the first inner surface and the first outer surface are disposed between the first surface and the second surface; A second sealing member defining a closed shape comprises: third surface; a fourth surface opposite to the third annular surface; a second inner surface; and a second outer surface opposite to the second inner surface, wherein the second inner surface and the second outer surface are disposed between the third surface and the fourth surface; a first longitudinal sealing member connected between the first outer surface and the second outer surface; and A second longitudinal sealing member is connected between the first outer surface and the second outer surface.

2. The sealing gasket according to claim 1, wherein: The first sealing member defines a rounded square or a rounded rectangle; The first surface is a surface in the shape of a rounded square or a rounded rectangle; and The second surface is a surface in the shape of a rounded square or a rounded rectangle.

3. The sealing gasket according to claim 2, wherein: The first sealing member comprises: a first arc section; a second arc section; The third arc section; the fourth arc segment; a first substantially straight section disposed between the first arcuate section and the second arcuate section; a second substantially straight section disposed between the second arcuate section and the third arcuate section; a third substantially straight section disposed between the third arcuate section and the fourth arcuate section; and a fourth substantially straight section disposed between the fourth arcuate section and the first arcuate section; wherein The first longitudinal sealing member is connected to the first arcuate segment; and The second longitudinal sealing member is connected to the third arcuate segment.

4. A sealing gasket as claimed in any preceding claim, wherein: The second sealing member defines a rounded square or a rounded rectangle; The third surface is a surface in the shape of a rounded square or a rounded rectangle; and The fourth surface is a surface in the shape of a rounded square or a rounded rectangle.

5. The sealing gasket according to claim 4, wherein: The second sealing member includes the fifth arc segment; the sixth arc segment; seventh arc segment; the eighth arc segment; a fifth substantially straight section disposed between the fifth arcuate section and the sixth arcuate section; a sixth substantially straight segment disposed between the sixth arcuate segment and the seventh arcuate segment; a seventh substantially straight segment disposed between the seventh arcuate segment and the eighth arcuate segment; and an eighth substantially straight segment disposed between the eighth arcuate segment and the fifth arcuate segment; in The first longitudinal sealing member is connected to the fifth arcuate segment; and The second longitudinal sealing member is connected to the seventh arcuate segment.

6. A sealing gasket as claimed in any preceding claim, wherein: The sealing gasket is a one-piece gasket.

7. A sealing gasket as claimed in any preceding claim, wherein: The sealing gasket is a molded gasket.

8. A sealing gasket as claimed in any preceding claim, wherein: Some or all of the sealing gaskets may have a square or rectangular cross-section.

9. A sealing gasket as claimed in any preceding claim, wherein: The sealing gasket is deformable.

10. A sealing gasket as claimed in any preceding claim, wherein: The sealing gasket is an elastomer.

11. A vacuum pump comprising: a housing stator defining at least one pumping chamber; an end piece mountable at either end of the housing stator; as well as A sealing gasket as claimed in any preceding claim.

12. The vacuum pump of claim 11, wherein: The sealing gasket is according to claim 3 or any claim dependent on claim 3; The first sealing member is disposed in the first sealing groove; The first arcuate segment is disposed in a first substantially straight portion of the first sealing groove; The second arcuate segment is disposed in a second substantially straight portion of the first sealing groove; The third arcuate segment is disposed in a third substantially straight portion of the first sealing groove; The fourth arcuate segment is disposed in a fourth substantially straight portion of the first sealing groove; The first substantially straight section is disposed in a first arcuate portion of the first sealing groove; The second substantially straight section is disposed in a second arcuate portion of the first sealing groove; The third substantially straight section is disposed in a third arcuate portion of the first sealing groove; and The fourth substantially straight section is disposed in a fourth arcuate portion of the first sealing groove.

13. A vacuum pump according to claim 11 or 12, wherein: The sealing gasket is according to claim 5 or any claim dependent on claim 5; The second sealing member is disposed in the second sealing groove; The fifth arcuate segment is disposed in a first substantially straight portion of the second sealing groove; The sixth arcuate segment is disposed in a second substantially straight portion of the second sealing groove; The seventh arcuate segment is disposed in a third substantially straight portion of the second sealing groove; The eighth arcuate segment is disposed in a fourth substantially straight portion of the second sealing groove; The fifth substantially straight section is disposed in the first arcuate portion of the second sealing groove; The sixth substantially straight section is disposed in a second arcuate portion of the second sealing groove; The seventh substantially straight section is disposed in a third arcuate portion of the second sealing groove; and The eighth substantially straight section is disposed in a fourth arcuate portion of the second sealing groove.

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