Integrated seal

Abstract

To obtain an integrated seal with excellent rigidity and corrosion resistance. [Solution] The integrated seal 1 comprises an annular sealing member 2 that makes airtight contact with the outer circumferential surface of the shaft member, an annular outer member 3 that covers at least the outer circumferential surface and one axial surface 2b of the sealing member 2, and an annular inner member 4 that covers the other surface 2c of the sealing member 2 opposite to the axial surface 2b on the inner side of the outer member 3. The inner member 4 is fixed to the outer member 3, thereby fixing the sealing member 2. The sealing member 2 comprises a sealing member body 2a sandwiched between the outer member 3 and the inner member 4, and at least a pair of bifurcated lip portions 2d, 2e that extend radially inward from the inner circumferential side of the sealing member body 2a. A groove portion 6 is formed in the bifurcated portion of the pair of lip portions 2d, 2e, extending radially inward beyond the inner diameter of the outer annular portion 3a that extends radially from the outer member 3 and covers one surface 2b of the sealing member 2.

Description

Technical Field

[0001] The present invention relates to an integral seal used as a shaft seal for a vacuum pump, a compressor, an EGR valve, etc.

Background Art

[0002] As this type of integral seal, conventionally, for example, as in Patent Document 1, an integral seal having a seal member composed of one part provided with a hinge groove on the atmosphere side of the first seal lip and a wiper lip for preventing the entry of dust from the atmosphere side is known.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the integral seal as in Patent Document 1, a resin molded product having a certain degree of flexibility and rigidity is used, but its moldability and sizing property are not sufficient, so there is a risk of problems such as cracking during use.

[0005] The present invention has been made in view of such points, and its object is to obtain a highly durable integral seal excellent in moldability and sizing property.

Means for Solving the Problems

[0006] In order to achieve the above object, in this invention, the shape of the seal member is devised.

[0007] Specifically, the integral seal of the first invention is an annular seal member that is in sealing contact with the outer peripheral surface of the shaft member, and An annular outer member covering at least the outer circumferential surface and one axial side of the sealing member, The outer member comprises an annular inner member on its inner surface side, which covers the other surface of the sealing member opposite to one surface in the axial direction. The inner member is fixed to the outer member, thereby fixing the sealing member. The sealing member is A sealing member body is sandwiched between the outer member and the inner member, The sealing member body comprises at least one pair of lip portions that extend radially inward from the inner circumference and are bifurcated, A groove is formed in the crotch of the pair of lip portions, extending radially inward beyond the inner diameter of the outer annular portion that extends radially from the outer member and covers one surface of the sealing member.

[0008] According to the above configuration, grooves of appropriate depth are formed in the crotch of the pair of lip sections, making it easier to ensure moldability and shape retention, and reducing the likelihood of excessive force being applied during use, thereby suppressing the occurrence of defects such as cracking. Furthermore, by fixing the inner member to the outer member, the sealing member can be sandwiched and fixed in the axial direction to form a unit component, thus reducing the number of parts, making installation easier and saving space. Here, "sealed" refers to a state in which, when the shaft member rotates, the sealing member contacts the outer surface of the shaft member to the extent that it does not hinder the rotation, thereby suppressing the flow of fluid from one side to the other.

[0009] In the second invention, in the first invention, The inner member has an L-shaped cross-section, the inner annular portion extending radially of the inner member covers the other surface of the sealing member, and the outer peripheral surface extending axially of the inner member is in contact with the inner peripheral surface extending axially of the outer member. The sealing member body is sandwiched between the inner annular portion and the outer annular portion.

[0010] According to the above configuration, the inner member is in surface contact with the outer member and securely fixed, and the sealing member body is protected by the inner annular portion and the outer annular portion.

[0011] In the third invention, in the second invention, Of the pair of lip portions, the lip portion located on the inner annular portion side is further divided into a pair of lip portions, and the groove portion is also formed at the base of the further divided pair of lip portions.

[0012] According to the above configuration, since the lip section is divided into three parts, it can receive pressure in a divided manner compared to a configuration with two lip sections. This reduces the pressure applied to each lip section, making it less likely for excessive force to be applied to each lip section during use, thereby suppressing the occurrence of defects such as cracking.

[0013] In the fourth invention, in the first invention, Of the pair of lip portions, the lip portion located on the outer annular portion side constitutes a dust lip that prevents dust from entering.

[0014] According to the above configuration, even in usage situations where a dust lip is required, the sealing member is integrated with the dust lip, resulting in a single-piece seal that reduces the number of parts and suppresses the occurrence of defects such as cracking.

[0015] In the fifth invention, in any one of the first inventions, Of the pair of lip portions, the lip portion on the outer annular portion side has its tip bent toward the inner annular portion side, similar to the lip portion on the inner annular portion side.

[0016] According to the above configuration, the pair of lip portions can be housed between the outer member and the inner member, thus protecting the sealing member during transport and making it easier to handle. Furthermore, it is advantageous that the pair of lip portions can absorb the pressure when the fluid pressure on the side where the pair of lip portions are bent is high.

[0017] In the sixth invention, in any one of the first to fifth inventions, the inner member covers the other surface of the seal member body via an annular gasket, and the inner diameter of the gasket is not less than the inner diameter of the bottom surface of the groove portion of the pair of lip portions.

[0018] According to the above configuration, without adversely affecting the shape of the gasket formed by the seal member, the movable range is increased, and leakage (internal leakage) passing between the inner member and the seal member can be prevented.

[0019] In the seventh invention, in any one of the first to fifth inventions, the outer member covers one surface of the seal member body via an annular gasket, and the inner diameter of the gasket is not less than the inner diameter of the bottom surface of the groove portion of the pair of lip portions.

[0020] According to the above configuration, without adversely affecting the shape of the gasket formed by the seal member, leakage (internal leakage) passing between the outer member and the seal member can be prevented.

Effect of the Invention

[0021] As described above, according to the present invention, an integral seal excellent in formability, setting property, and durability can be obtained.

Brief Description of the Drawings

[0022] [Figure 1A] It is a cross-sectional view showing an integral seal according to an embodiment of the present invention. [Figure 1B] It is a perspective view showing an integral seal with a part broken away. [Figure 1C] It is a cross-sectional view showing an integral seal according to an embodiment of the present invention when inserted into a shaft member. [Figure 2]This is a cross-sectional view corresponding to Figure 1A showing an integrated seal according to a modified example of the present invention. [Figure 3] This is a cross-sectional view corresponding to Figure 1A showing an integrated seal according to a modified example 2 of the embodiment of the present invention. [Figure 4] This is a cross-sectional view corresponding to Figure 1A showing an integrated seal according to a modified example 3 of the present invention. [Figure 5] This is a cross-sectional view corresponding to Figure 1A showing an integrated seal according to a modified example 4 of the embodiment of the present invention. [Figure 6] This is a cross-sectional view corresponding to Figure 1A showing an integrated seal according to a modified example 5 of the present invention. [Figure 7] This is a cross-sectional view corresponding to Figure 1A showing an integrated seal according to a modified example 6 of the present invention. [Figure 8] This is a cross-sectional view corresponding to Figure 1A showing an integrated seal according to a modified example 7 of the embodiment of the present invention. [Figure 9] This is a cross-sectional view corresponding to Figure 1A showing an integrated seal according to a modified example 8 of the embodiment of the present invention. [Modes for carrying out the invention]

[0023] Embodiments of the present invention will be described below with reference to the drawings.

[0024] Figures 1A to 1C show an integrated seal 1 according to an embodiment of the present invention, which comprises an annular sealing member 2 that tightly contacts the outer circumferential surface of a shaft member (not shown) having a circular cross-section. The sealing member 2 is made of a resin material such as nylon, polyethylene, or polytetrafluoroethylene (PTFE), which is chemically stable and has excellent heat resistance and chemical resistance, or a rubber material.

[0025] The integrated seal 1 also includes an annular outer member 3 that covers the outer circumferential surface and one axial surface 2b of the seal member 2. This outer member 3 is, for example, an annular shape formed by bending both axial ends, and is preferably made of a metal such as a stainless steel plate or cold-rolled steel plate. For parts of the outer member 3 that require corrosion resistance, a highly corrosion-resistant material such as a stainless steel plate is suitable, but in some cases, it may not be made of a metal material as long as it is a rigid body that can be bent. The outer member 3 includes an outer-side annular portion 3a that extends radially and covers one surface 2b of the seal member 2.

[0026] The integrated seal 1 includes an annular inner member 4 on the inner surface side of the outer member 3, covering the other surface 2c of the seal member 2 opposite to the axial surface 2b. This inner member 4 is preferably made of a metal such as stainless steel or cold-rolled steel, but may be made of a rigid material that can be bent. For areas requiring corrosion resistance, highly corrosion-resistant materials such as stainless steel are suitable.

[0027] The inner annular portion 4a of the inner member 4 and the opposite end 4c on the axial side are fixed by, for example, pressing them against the opposite end 3c on the axial side of the outer annular portion 3a of the outer member 3, but they may also be crimped together. By fixing the inner member 4 to the outer member 3 in this way, the seal member 2 is fixed as a result.

[0028] In this embodiment, the inner member 4 covers the other surface 2c of the sealing member body 2a, which has a rectangular cross-section, via an annular gasket 5. The gasket 5 may be made of the same material as the sealing member 2, but a more flexible rubber material that is more easily compressed than the sealing member 2 is preferable.

[0029] The inner member 4 has an L-shaped cross-section, and the radially extending inner annular portion 4a of the inner member 4 covers the other surface 2c of the seal member 2. The axially extending outer peripheral surface 4b of the inner member 4 is in contact with the axially extending inner peripheral surface 3b of the outer member 3, and the seal member body 2a is sandwiched between the inner annular portion 4a and the outer annular portion 3a.

[0030] The sealing member 2 comprises at least one pair of lip portions 2d and 2e that extend radially inward from the inner circumference of the sealing member body 2a, which has a rectangular cross-section, and are bifurcated.

[0031] Of the pair of lip portions 2d and 2e, the lip portion 2d located on the outer annular portion 3a side constitutes a dust lip that prevents dust from entering.

[0032] Furthermore, grooves 6 are formed in the crotch portions of the pair of lip portions 2d and 2e, extending radially further inward than the inner diameter of the outer annular portion 3a.

[0033] As shown in Figure 1C, when the integrated seal 1 is inserted into a cylindrical or cylindrical shaft member 10, the pair of lip portions 2d and 2e deform in a direction that separates them from each other, thereby achieving sealing performance.

[0034] The inner diameter of the gasket 5 is greater than or equal to the inner diameter of the bottom surface of the groove 6 of the pair of lip portions 2d and 2e.

[0035] As described above, in this embodiment, a groove 6 of an appropriate depth is formed in the crotch of the pair of lip portions 2d and 2e, which makes it easier to ensure the moldability and shapeability of the resin sealing member 2, and reduces the likelihood of excessive force being applied during use, thereby suppressing the occurrence of defects such as cracking.

[0036] Furthermore, by fixing the inner member 4 to the outer member 3, the seal member 2 can be sandwiched and fixed in the axial direction to form a unit component, thus reducing the number of parts, making installation easier and saving space. In particular, in this embodiment, since one lip portion 2d constitutes a dust lip, an integrated seal 1 can be obtained that suppresses the intrusion of dust, reduces the number of parts, and suppresses the occurrence of defects such as cracking.

[0037] In this embodiment, the inner member 4 is in surface contact with the outer member 3 and is securely fixed, allowing the two to firmly hold and protect the seal member body 2a.

[0038] In this embodiment, the inner diameter of the gasket 5 is made larger than the inner diameter of the groove 6, so that leakage (internal leakage) passing between the inner member 4 and the seal member 2 can be prevented without adversely affecting the shape of the seal member 2.

[0039] Therefore, according to the present invention, a highly durable, one-piece seal 1 with excellent moldability and shape retention can be obtained.

[0040] -Experimental Variation 1- Figure 2 shows a modified example 1 of the present invention, which is an integrated shaft seal 101, and differs from the above embodiment in that the shape of the lip portion 102d on the outer annular portion 3a side of the seal member 102 is different. In each modified example, the same reference numerals are used for the same parts as in Figures 1A and 1B, and their detailed descriptions are omitted.

[0041] In this modified example, the lip portion 102d has a longer tip and a thicker plate thickness than the lip portion 2d in the above embodiment. Rather than functioning as a dust lip, this lip portion 102d works in cooperation with the lip portion 2e on the inner annular portion 4a side to improve sealing performance.

[0042] Even in such cases, the effect of the groove 6 makes it possible to obtain a highly durable, integrated seal 101 with excellent moldability and shape retention. This integrated seal 101 is suitable for sealing different liquids on the lip portion 2e side and the lip portion 102d.

[0043] -Variation 2- Figure 3 shows a modified example 2 of the present invention, which differs from the above embodiment in that the shape of the lip portion 202d on the outer annular portion 3a side of the sealing member 202 is different.

[0044] Although the lip portion 202d of this modified example does not extend as far as in the first modified example, even in this case, the groove portion 6 allows for the creation of a highly durable, integrated seal 201 with excellent moldability and shape retention.

[0045] -Variation 3- Figure 4 shows a shaft-integrated seal 301 according to a modified example 3 of the present invention, which differs from the above embodiment in that the shape of the lip portion 302d on the outer annular portion 3a side of the seal member 302 is different.

[0046] In this modified example, the lip portion 302d constitutes a dust lip, and a cutback portion 302e is formed in the part covered by the outer annular portion 3a, with a portion of it being cut out. The thickness is reduced by this cutback portion 302e, making the lip portion 302d more flexible at the cutback portion 302e. This reduces the reaction force on the lip portion 302d, which has the advantage of making it less prone to wear.

[0047] -Variation 4- Figure 5 shows a shaft-integrated seal 401 according to a modified example 4 of the present invention, in which the axial thickness of the seal member body 402a in the seal member 402 is thicker than that of the earlier embodiment. Accordingly, the width of the groove 6 is also widened. By widening the width of the groove 6, heat is less likely to accumulate when the pair of lip portions 2d and 2e generate heat due to frictional heat.

[0048] As can be seen from this modified example, for instance, the side wall of the groove 6 is composed of the root end portions of the pair of lip portions 2d and 2e, but it may be thicker than the root end portions of the pair of lip portions 2d and 2e.

[0049] -Variation 5- Figure 6 shows a shaft-integrated seal 501 according to modified example 5 of the present invention, which differs from modified example 4 shown in Figure 5 in that the lip portion 502d on the outer annular portion 3a side of the seal member 502 faces the inner annular portion 4a side.

[0050] As shown in Figure 6, in this modified example, of the pair of lip portions 502d and 2e, the lip portion 502d on the outer annular portion 3a side has its tip bent toward the inner annular portion 4a side, similar to the lip portion 2e on the inner annular portion 4a side.

[0051] In this modified example, the pair of lip portions 502d and 2e can be housed between the outer member 3 and the inner member 4, thus protecting the sealing member 2 during transport and making it easier to handle. Furthermore, when the pressure on the inner annular portion 4a is high, the pair of lip portions 502d and 2e can share the pressure, which is an advantage.

[0052] -Variation 6- Figure 7 shows a shaft-integrated seal 601 according to modification 6 of the embodiment of the present invention, which differs from modification 4 in that the shape of the lip portion 602d on the outer annular portion 3a side of the seal member 602 is different. In addition, a gasket 5 is not provided in this modification.

[0053] In this modified example, the sealing member body 602a is wide, similar to the modified example 4 shown in Figure 5, and the lip portion 602d is a normal sealing lip, unlike the lip portion 402d which serves as a dust lip in modified example 4. Even in this case, the effect of the groove portion 6 makes it possible to obtain a highly durable, integrated seal 601 with excellent moldability and shape retention.

[0054] -Variation 7- Figure 8 shows a shaft-integrated seal 701 according to modified example 7 of the embodiment of the present invention, which differs from modified example 5 shown in Figure 6 in that one of the pair of lip portions is further divided into two.

[0055] The sealing member body 702a of this modified example is also wide, similar to modified example 5. Of the pair of lip portions 702d and 702e, the lip portion 702e on the inner annular portion 4a side is further divided into a pair of lip portions 702e and 702f, and groove portions 6 are also formed at the base of the further divided pair of lip portions 702e and 702f.

[0056] In this modified version, since the lip portion is divided into three parts, excessive force is less likely to be applied to each lip portion 702d, 702e, and 702f during use, thereby suppressing the occurrence of defects such as cracking. Also, since all three lip portions 702d, 702e, and 702f face the inner annular portion 4a, it is suitable when the pressure on the inner annular portion 4a side is high.

[0057] -Variation 8- Figure 9 shows a modified example 8 of the present invention, which is an integrated shaft seal 801, and differs from modified example 7 shown in Figure 8 in that the shape of the lip portion 802d on the outer annular portion 3a side is different.

[0058] In this modified example, the lip portion 802d functions as a dust lip. Even in this case, the effect of the groove portion 6 makes it possible to obtain a highly durable, integrated seal 801 with excellent moldability and shape retention.

[0059] The embodiments described above are essentially preferred examples and are not intended to limit the scope of the present invention, its applications, or uses.

[0060] For example, the gasket 5 provided in the above embodiment does not necessarily need to be provided in examples other than the modified example 6. Although not shown, the outer member 3 may cover one surface 2b of the seal member body 2a via the annular gasket 5. In this case as well, it is desirable that the inner diameter of the gasket 5 is greater than or equal to the inner diameter of the bottom surface of the groove 6 of the pair of lip portions 2d, 2e. Even in such a case, the gasket 5 can prevent leakage (internal leakage) passing between the outer member 3 and the seal member 2 without adversely affecting the shape of the seal member 2.

[0061] Furthermore, although the surface of each lip portion is flat in the above embodiment, grooves or the like may be machined into the surface. [Explanation of Symbols]

[0062] 1. Integrated seal 2 sealing member 2a Sealing member body 2b side 2c other side 2d, 2e Lip section 3 Outer members 3a Outer annular section 3b Inner surface 3c Opposite end 4 Inner components 4a Inner annular section 4b Outer surface 4c Opposite end 5 Gasket 6 grooves 10 Shaft member 101 Integrated Seal 102 Sealing member 102d Lip section 201 Integrated Seal 202 Sealing component 202d Lip section 301 Integrated Seal 302 Sealing component 302d Lip section 302e Cutback section 401 Integrated Seal 402 Sealing component 402a Sealing component body 402d Lip section 501 Integrated Seal 502 Sealing component 502d Lip section 601 Integrated Seal 602 Sealing component 602a Sealing component body 602d Lip section 701 Integrated Seal 702 Sealing component 702a Sealing component body 702d, 702e, 702f Lip section 801 Integrated Seal 802d Lip section

Claims

1. An annular sealing member that makes airtight contact with the outer surface of the shaft member, An annular outer member covering at least the outer circumferential surface and one axial side of the sealing member, The outer member comprises an annular inner member on its inner surface side, which covers the other surface of the sealing member opposite to one surface in the axial direction. The inner member is fixed to the outer member, thereby fixing the sealing member. The sealing member is A sealing member body is sandwiched between the outer member and the inner member, The sealing member body comprises at least one pair of lip portions that extend radially inward from the inner circumference and are bifurcated, A groove is formed in the crotch of the pair of lip portions, extending radially inward beyond the inner diameter of the outer annular portion that extends radially from the outer member and covers one surface of the sealing member. A one-piece seal characterized by the following features.

2. The inner member has an L-shaped cross-section, the inner annular portion extending radially of the inner member covers the other surface of the sealing member, and the outer peripheral surface extending axially of the inner member is in contact with the inner peripheral surface extending axially of the outer member. The sealing member body is sandwiched between the inner annular portion and the outer annular portion. The integrated seal according to feature 1.

3. Of the pair of lip portions, the lip portion on the inner annular portion side is further divided into a pair of lip portions, and the groove portion is also formed at the base of the further divided pair of lip portions. The integrated seal according to feature 2.

4. Of the pair of lip portions, the lip portion located on the outer annular portion side constitutes a dust lip that prevents dust from entering. The integrated seal according to feature 1.

5. Of the pair of lip portions, the lip portion on the outer annular portion side has its tip bent toward the inner annular portion, similar to the lip portion on the inner annular portion side. The integrated seal according to feature 2.

6. The inner member covers the other side of the sealing member body via an annular gasket. The inner diameter of the gasket is greater than or equal to the inner diameter of the bottom surface of the groove of the pair of lip portions. An integrated seal according to any one of features 1 to 5.

7. The outer member covers one surface of the sealing member body via an annular gasket. The inner diameter of the gasket is greater than or equal to the inner diameter of the bottom surface of the groove of the pair of lip portions. An integrated seal according to any one of features 1 to 5.

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