JP2007218366A - Seal with shaft - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a seal with a shaft having an improved service life by suppressing the wear of a third seal and preventing the intrusion of dust such as muddy water into a sealed fluid caused by the degradation of interference resulting from early wear. <P>SOLUTION: The seal with the shaft comprises a first seal 10 mounted to the shaft 2 and having a sleeve 11 on an atmosphere side A whose flange 13 extends toward the outer diameter, a second seal 20 mounted to a housing 3 and having a second seal body 25 in slide-contact with the first seal 10, a protecting ring 30 provided on the atmosphere side A at a predetermined axial space from a flange 13, and the third seal 40 mounted via a joint 41 of a rubber elastic body adhered to the flange 13 and having a resin third seal body 42 which slides in face-contact with the protecting ring 30. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a shaft-attached seal used for sealing a shaft seal portion of an agricultural machine, a construction machine or the like used in an environment where dust conditions such as muddy water on the atmosphere side are severe.

  Conventionally, the shaft seal shown in FIG. 3 is known as a shaft seal used for sealing a shaft seal portion of an agricultural machine or a construction machine used in an environment where dust conditions such as muddy water on the atmosphere side are severe. (See Patent Document 1 below). The shaft-attached seal 100 seals between the shaft 101 and the housing 102 that move relative to each other, and includes a first seal 110, a second seal 120, a protective ring 130, and a third seal 140. , And a dust seal 150.

  The first seal 110 includes a sleeve 111 having a cylindrical portion 112 extending in the axial direction and fitted to the shaft 101, a flange portion 113 extending in the outer diameter direction from the atmosphere side A end of the cylindrical portion 112, and the cylindrical portion 112. And a rubber-like elastic first seal main body 115 that is mounted on the inner peripheral side and seals between the shaft 101.

  The second seal 120 includes an outward flange portion 123 extending in the outer diameter direction from the atmospheric end A of the cylindrical portion 122 fitted to the housing 102 and an inward flange extending in the inner diameter direction from the end of the sealing fluid side B. A reinforcing ring 121 having a portion 124, and a rubber-like elastic second seal main body 125 bonded to the cylindrical portion 122 and the inward flange portion 124 of the reinforcing ring 121. The second seal body 125 extends to the sealing fluid side B, slides on the outer peripheral surface of the cylindrical portion 112 of the first seal 110, and extends to the atmosphere side A of the cylindrical portion 112 of the first seal 110. And a second seal lip 127 and a third seal lip 128 that slide on the outer peripheral surface, and a fourth seal lip 129 that extends to the atmosphere side A and slides on the end surface of the flange portion 113 of the sleeve 111 on the sealing fluid side B. A garter spring 126 a for applying a radial tension force is mounted on the outer peripheral side of the first seal lip 126.

  The protective ring 130 is provided on the atmosphere side A with a predetermined axial distance from the flange portion 113 of the sleeve 111, and the outer peripheral portion 132 of the radially extending flange portion 131 is the outward flange portion of the second seal portion 120. The flange portion 131 has a cylindrical portion 133 that extends to the sealed fluid side B. The flange portion 131 is in contact with the atmosphere side A end surface of 123 and fixed by a crimping portion 123a.

  The third seal 140 includes a third seal main body portion 145 made of a rubber-like elastic body that adheres to the flange portion 113 of the sleeve 111 and slides on the sealing fluid side B end surface of the flange portion 131 of the protective ring 130.

  The third seal body portion 145 is formed integrally with the first seal body portion 115 and has a predetermined interval in the radial direction inclined in the inner diameter direction sliding on the sealing fluid side B end surface of the flange portion 131 of the protective ring 130. The first seal lip 146 and the second seal lip 147 are provided.

  The dust seal 150 is formed integrally with the end A on the atmosphere side of the first seal main body 115, extends with an inclination in the outer diameter direction, and has a dust seal lip 155 that slides on the inner peripheral surface of the cylindrical portion 133 of the protective ring 130. Have.

  As a result, the dust seal 150 seals intrusion of dust such as muddy water from the atmosphere side A. Further, the intruded dust such as muddy water is sealed by the first seal lip 146 and the second seal lip 147 of the third seal 140. Therefore, dust such as muddy water is prevented from entering (leaking) into the sealed fluid side B.

  However, with the conventional configuration described above, the first seal lip 146 and the second seal lip 146 of the third seal 140 are caused by dust such as muddy water that has entered from the dust seal 150 when used under particularly severe conditions such as muddy water. Since the seal lip 147 is worn out early and the tightening allowance is reduced, there is a problem that intrusion of dust such as muddy water into the sealed fluid side B is recognized before the required life is reached.

  Patent Document 2 below discloses that the third seal main body is formed separately and is slid between the flange portion of the sleeve and the protective ring. However, the object and configuration are different from those of the present invention. I have to.

JP 2000-193097 A Japanese Patent Application Laid-Open No. 08-200515

  The present invention has been made to solve the above-described problems, and the object of the present invention is to suppress the wear of the third seal and to reduce dust such as muddy water due to a decrease in tightening allowance caused by early wear. It is to prevent the leakage (intrusion) from entering the sealed fluid side, thereby improving the life of the shaft seal.

  Another object is to improve the sealing performance of the third seal in order to prevent dust such as muddy water from entering the sealed fluid side in a particularly severe environment.

  To achieve the above object, a shaft-attached seal according to claim 1 of the present invention is provided in an annular space between a shaft and a housing that move concentrically relative to each other, and seals the sealing fluid on the sealing fluid side. And a sleeve having a flange portion that is attached to the shaft and extends in the outer diameter direction on the atmosphere side, and a first seal body that seals the outer peripheral surface of the shaft. A second seal comprising a first seal provided with a portion, a reinforcing ring mounted on the housing and sliding on the first seal, and the flange portion and the axial direction. A third of a resin that is attached via a protective ring provided on the atmosphere side having a predetermined interval and a rubber-like elastic body bonded to the flange portion, and that slides in surface contact with the protective ring. A third seal having a seal body, and And it is characterized in and.

  Furthermore, the seal with a shaft according to claim 2 is the seal with a shaft according to claim 1, wherein a ring of a rubber-like elastic body having a lip shape is interposed between the third seal body portion and the coupling portion. It is characterized by having made it.

  The present invention has the following effects.

  That is, in the seal with a shaft according to claim 1 having the above-mentioned configuration, the third seal main body portion is excellent in low friction because it is formed of resin, and wears even if it slides on the protective ring in surface contact. Is suppressed. Therefore, it is possible to prevent the dust from entering the sealing fluid side by reducing the sealing performance due to the decrease in the tightening allowance due to the early wear of the third seal main body, and to prevent the dust from entering the sealing fluid side. Lifespan can be improved.

  In addition, since the third seal main body slides in contact with the protective ring in surface contact, the seal area is expanded, and since it is mounted via a rubber-like elastic joint, adequate surface pressure and followability are ensured. As a result, the sealing performance against dust such as muddy water can be improved, and thus the life of the shaft seal can be improved.

  In addition to this, the seal with a shaft according to claim 2 has a rubber-like elastic ring having a lip shape interposed between the third seal body portion and the coupling portion. Followability and compression stability can be further improved, and the sealing performance can be further improved.

  Exemplary embodiments of the present invention will be described below with reference to the drawings.

1st Embodiment FIG. 1: has shown the principal part cross section of the seal with a shaft which concerns on the 1st Example of this invention, and is comprised as follows.

  The shaft-attached seal 1 is provided in an annular space between the shaft 2 and the housing 3 which are concentrically moved relative to each other, and includes a first seal 10, a second seal 20, a protective ring 30, and the like. The third seal 40 and the dust seal 50 are provided.

  The first seal 10 extends in the axial direction and is fitted with the shaft 2, the flange portion 13 extending in the outer diameter direction from the atmosphere side A end of the inner diameter cylindrical portion 12, and the outer diameter end of the flange portion 13. A sleeve 11 having an outer diameter cylindrical portion 14 extending from the portion to the atmosphere side A, and a first seal main body portion 15 of a rubber-like elastic body that adheres to the inner peripheral side of the inner diameter cylindrical portion 12 and seals between the shaft 2 and It is equipped with.

  The second seal 20 has an outward flange portion 23 extending in the outer diameter direction from the atmospheric end A of the cylindrical portion 22 fitted in the housing 3 and an inward flange extending in the inner diameter direction from the end of the sealing fluid side B. A reinforcing ring 21 having a portion 24, and a second seal body portion 25 made of a rubber-like elastic body bonded to a cylindrical portion 22 and an inward flange portion 24 of the reinforcing ring 21 are provided. The second seal body 25 extends to the sealing fluid side B and slides on the outer peripheral surface of the inner diameter cylindrical portion 12 of the first seal 10, and the inner diameter cylindrical portion of the first seal 10 extends to the atmosphere side A. 12 and the second seal lip 27 and the third seal lip 28 provided at predetermined intervals in the axial direction sliding on the outer peripheral surface of the sleeve 12, and also extending to the atmosphere side A and the sealing fluid side of the flange portion 13 of the sleeve 11 A garter spring 26a is provided on the outer peripheral side of the first seal lip 26 to apply a compressive force in the radial direction.

  The protective ring 30 is provided on the atmosphere side A with a predetermined axial distance from the flange portion 13 of the sleeve 11, and a protective first flange portion 31 extending in the radial direction, and an outer diameter end of the first protective flange portion 31. A protective outer diameter cylindrical portion 32 extending from the portion to the sealed fluid side B, a protective second flange portion 33 extending from the protective outer diameter cylindrical portion 32 in the outer diameter direction, and a sealed fluid from the inner diameter side end of the protective first flange portion 31. And a protective inner diameter cylindrical portion 34 extending to the side B. The protective second flange portion 33 abuts on the atmosphere-side A end surface of the outward flange portion 23 of the second seal 20 and is fixed by crimping at the crimping portion 23a.

  The dust seal 50 is integrally formed with the atmosphere-side A end of the first seal main body 15, extends in an inclined direction in the outer diameter direction, and slides on the inner peripheral surface of the protective inner diameter cylindrical portion 34 of the protective ring 30. 51.

  The third seal 40 is bonded to the atmosphere-side end surface of the flange portion 13 of the sleeve 11 and is joined to the atmosphere-side A of the coupling portion 41 with a rubber-like elastic coupling portion 41 formed integrally with the first seal main body portion 15. A third seal body 42 is provided.

  The third seal main body 42 has a rectangular cross section formed of resin Teflon (registered trademark), the sealing fluid side B end surface is mounted and fixed to the coupling portion 41, and the atmosphere side A end surface is protected. It mounts | wears with the sealing fluid side B end surface of the protection 1st flange part 31 of the ring 30 so that it may slide by surface contact.

  In the shaft-equipped seal 1 having the above-described configuration, the third seal main body portion 42 is formed of Teflon (registered trademark), which is a resin, so that it has excellent low friction and seals the protective first flange portion 31 of the protective ring 30. Abrasion is suppressed even if the fluid side B end surface slides in surface contact. Accordingly, it is possible to prevent the dust from entering the sealing fluid side B by reducing the sealing performance against the dust such as muddy water due to the reduction of the tightening allowance due to the early wear of the third seal main body portion 42, and the shaft It becomes possible to improve the lifetime of the attached seal 1.

  Further, since the third seal main body 42 slides on the protective first flange portion 31 in surface contact, the seal area is increased, and the third seal main body portion 42 is mounted through the rubber-like elastic coupling portion 41, so that it has an appropriate surface. The pressure and followability are ensured, and the sealing performance against dust such as muddy water can be improved. Therefore, the life of the shaft seal 1 can be improved.

2nd Embodiment FIG. 2: has shown the principal part cross section of the seal | sticker 1 with a shaft which concerns on the 2nd Example of this invention. In the second embodiment, the third seal 40 is different from the first embodiment in that a rubber-like elastic ring 43 having a lip shape 44 is interposed between the third seal main body portion 42 and the coupling portion 41. Different.

  Therefore, in the second embodiment, in addition to the same effect as in the first embodiment, in addition to this, a ring 43 of a rubber-like elastic body made of a lip shape 44 is provided with the third seal main body portion 42 and the coupling portion 41. Therefore, the followability and compression stability of the third seal body 42 made of Teflon (registered trademark) can be obtained.

1 is a partial cross-sectional view of a shaft seal according to a first embodiment of the present invention. Partial sectional view of a shaft-mounted seal according to a second embodiment of the present invention Partial sectional view of a shaft-mounted seal according to a conventional example

Explanation of symbols

1 seal with shaft 2 shaft 3 housing 10 first seal 11 sleeve 12, 14, 22, 32, 34 cylindrical portion 13, 23, 24, 31, 33 flange portion 15, 25, 42 seal body portion 20 second seal 21 reinforcement Ring 23a Caulking part 26, 27, 28, 29, 51 Seal lip 26a Garter spring 30 Protective ring 40 Third seal 41 Coupling part 43 Ring 44 Lip shape 50 Dust seal A Atmosphere side B Sealed fluid side

Claims (2)

Provided in an annular space between the shaft and the housing that move concentrically relative to each other, seals the sealing fluid on the sealing fluid side, and seals dust such as muddy water on the atmosphere side,
A first seal provided with a sleeve having a flange portion attached to the shaft and extending in the outer diameter direction on the atmosphere side; and a first seal body portion for sealing the outer peripheral surface of the shaft;
A second seal that is mounted on the housing and includes a reinforcing ring and a second seal body that slides on the first seal;
A protective ring provided on the atmosphere side having a predetermined interval in the axial direction with the flange portion,
A third seal provided with a third seal body portion of resin that is mounted through a coupling portion of a rubber-like elastic body that is bonded to the flange portion, and that slides in surface contact with the protective ring;
A seal with a shaft characterized by comprising:   2. The shaft-attached seal according to claim 1, wherein a ring of a rubber-like elastic body having a lip shape is interposed between the third seal body portion and the coupling portion.

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