JP2007247708A - Seal with shaft - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the amount of dust to be sealed by a third seal, to suppress wear of the third seal to be worn by sealing dust, and to prevent dust from intruding into a sealing fluid side due to reduction of tightening allowance caused by early wear so as to improve the service life of a seal with a shaft. <P>SOLUTION: The seal with the shaft is provided with: a first seal 10 provided with a sleeve 11 having a flange part 13 mounted on the shaft 2 and extending in the direction of outside diameter on an atmosphere side A; a second seal 20 provided with a reinforcing ring 21 and a second seal main body part 25 coming into slide-contact with the first seal 10; a first protection ring 30 and a second protection ring 40 fixed on the reinforcing ring 21, having a predetermined interval in the axial direction among the flange part 13 and them, and provided on the atmosphere side A; a third seal 50 provided with a third seal main body part 55 adhering to the flange part 13 and sliding on the first protection ring 30; and a fourth seal 70 provided with a resin-made fourth seal main body part 71 nipped and held by the first protection ring 30 and the second protection ring 40 and sliding in a face contact with the shaft 2. <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 above-described conventional configuration, when the use conditions such as muddy water are used under particularly severe environments, the dust seal 150 cannot sufficiently seal, and a large amount of muddy water or the like that has passed through the dust seal 150. The first seal lip 146 and the second seal lip 147 of the third seal 140 are quickly worn out to reduce the tightening allowance, and dust such as muddy water moves to the sealed fluid side B before the required life is reached. A problem with intrusion was observed.

  In Patent Document 2 below, the third seal main body is molded from a separate resin, and is slid between the sleeve flange and the protective ring to improve the wear resistance of the third seal main body. However, the object and the configuration are different from those of the present invention.

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 reduce the amount of dust sealed with the third seal and wear the third seal by sealing the dust. In other words, it is possible to prevent the dust such as muddy water from entering (leaking) into the sealed fluid side due to a decrease in the tightening allowance due to the early wear, thereby improving the life of the shaft seal.

  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 including a first seal provided with a portion, a reinforcing ring mounted on the housing and sliding on the first seal, and fixed to the reinforcing ring. A first protective ring and a second protective ring provided on the atmosphere side with a predetermined axial distance from the flange part, and a third seal body part that adheres to the flange part and slides on the first protective ring. A third seal provided, the first protective ring and the first It is characterized in that and a fourth seal with the fourth seal body portion of resin is sandwiched between the protective rings to slide in surface contact with the shaft.

  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 connected to the cylindrical portion of the fourth seal body portion and the second protective ring. It is characterized by being interposed between the two.

  The present invention has the following effects.

  That is, in the seal with a shaft according to claim 1 having the above-described configuration, the fourth seal body portion sandwiched between the first protection ring and the second protection ring located on the atmosphere side slides in surface contact with the shaft. In addition, since dust such as muddy water on the atmosphere side enters the seal, the amount of dust sealed by the third seal is reduced, and the wear of the third seal main body due to sealing the dust is suppressed. be able to. Therefore, it is possible to prevent the dust from entering the sealing fluid side by reducing the sealing performance due to the lowering of the tightening allowance due to the early wear of the third seal body part, and to prevent the dust from entering the sealing fluid side. Can be improved.

  In addition, the fourth seal body is molded with resin, so it has excellent low friction properties and good wear resistance, so there is no deterioration in sealability due to wear, and it slides on the shaft in surface contact, so the seal area Therefore, the sealing performance against dust such as muddy water is good even at the end of life, and the amount of dust sealed with the third seal can be reduced.

  Furthermore, in addition to this, the shaft seal according to claim 2 has a rubber-like elastic ring having a lip shape interposed between the fourth seal body portion and the cylindrical portion of the second protective ring. Even when the shaft fluctuates, the followability and compression stability of the fourth seal body with respect to the shaft can be improved, and the sealing performance of the fourth seal can be 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, and a first protective ring. 30, a second protective ring 40, a third seal 50, a dust seal 60, and a fourth seal 70.

  The first seal 10 includes a sleeve 11 having a cylindrical portion 12 extending in the axial direction and fitted to the shaft 2, and a flange portion 13 extending in the outer diameter direction from an end portion on the atmosphere side A of the cylindrical portion 12, and the cylindrical portion 12. And a first elastic seal body 15 made of a rubber-like elastic body that adheres to the inner diameter side of the inner surface and seals between the shaft 2.

  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 main body 25 extends to the sealing fluid side B, slides on the outer peripheral surface of the cylindrical portion 12 of the first seal 10, and extends to the atmosphere side A of the cylindrical portion 12 of the first seal 10. 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, and the end surface of the sealing fluid side B of the flange portion 13 of the sleeve 11 extending to the atmosphere side A 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 first 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 extends in the radial direction from the first protective flange portion 31 and the first protective flange portion 31. A first protective outer peripheral portion 32 that is in contact with the atmosphere side A end surface of the outward flange portion 23 of the second seal 20 from the inner diameter side end portion of the first protective flange portion 31 to the sealed fluid side B. The first protective cylindrical portion 33 extends.

  The second protection ring 40 is provided on the atmosphere side A with a predetermined axial distance from the first protection flange portion 31 of the first protection ring 30, and extends in the radial direction. A second protective cylindrical portion 42 extending from the outer diameter side end of the protective flange portion 41 toward the sealed fluid side B, and a second protective outer periphery extending in the outer diameter direction from the sealed fluid side B end of the second protective cylindrical portion 42 Part 43.

  The sealing target side B end surface of the first protective outer peripheral portion 32 of the first protective ring 30 abuts on the atmospheric side A end surface of the outward flange portion 23 of the second seal 20, and the atmospheric side A end surface of the first protective outer peripheral portion 32. The sealing target side B end surface of the second protective outer peripheral portion 43 of the second protective ring 40 abuts, and the first protective outer peripheral portion 32 and the second protective outer peripheral portion 43 are caulked on the outward flange portion 23 of the second seal 20. The first protective ring 30 and the second protective ring 40 are attached at a predetermined interval in the axial direction by being caulked and fixed by the portion 23a.

  The third seal 50 includes a rubber-like elastic third seal main body 55 bonded to the flange portion 13 of the sleeve 11.

  The third seal main body 55 is formed integrally with the first seal main body 15, and is inclined in the radial direction in the inner diameter direction sliding on the sealing fluid side B end surface of the first protective flange portion 31 of the first protective ring 30. A first seal lip 56 and a second seal lip 57 are provided at a predetermined interval.

  The dust seal 60 is integrally formed with the third seal body 55 at the atmosphere side A end of the first seal body 15 and extends in an inclined direction in the outer diameter direction, and the first protection cylinder 33 of the first protection ring 30. And a dust seal lip 65 that slides on the inner peripheral surface of the.

  The fourth seal 70 includes a fourth seal body 71 that is sandwiched between the first protective flange 31 of the first protective ring 30 and the second protective flange 41 of the second protective ring 40.

  The fourth seal body 71 has a rectangular cross section formed of resin Teflon (registered trademark), and the inner peripheral surface 74 slides on the outer peripheral surface of the shaft 2 in surface contact. ing.

  In the seal with shaft 1 having the above-described configuration, the fourth seal body 71 is sandwiched between the first protection ring 30 and the second protection ring 40 and slides on the outer peripheral surface of the shaft 2 in surface contact. Since dust such as muddy water is sealed, the amount of dust passing through the dust seal 60 and sealed by the third seal 50 is reduced, and wear of the third seal main body 55 due to sealing of dust can be suppressed. Therefore, it is possible to prevent the tightening allowance due to the early wear of the third seal main body 55 from being reduced, and to prevent the sealing performance from being lowered. It becomes possible to prevent intrusion into the side B, and it is possible to improve the life of the shaft seal 1.

  Further, the fourth seal body 71 is formed of Teflon (registered trademark), which is a resin, so that it is excellent in low friction and wear is suppressed, so that the sealing performance is not deteriorated and the shaft 2 is in surface contact. Since it slides, the sealing area is large, and the sealing performance against dust such as muddy water is good even at the end of the life, and the amount of dust sealed by the third seal 50 can be reduced.

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, in the fourth seal 70, a rubber-like elastic ring having a lip shape 73 between the fourth seal body 71 and the inner diameter side end face of the second protective cylindrical portion 42 of the second protective ring 40 is used. The difference from the first embodiment is that 72 is interposed.

  Therefore, in the second embodiment, in addition to the same effect as the first embodiment, in addition to this, a ring 72 of a rubber-like elastic body made of a lip shape 73 is provided with the fourth seal body 71 and the second protective ring. 40, and the second protective cylindrical portion 42 is intervened. Therefore, even when the shaft 2 fluctuates, the followability and compression of the fourth seal main body portion 71 made of Teflon (registered trademark) with respect to the shaft 2 are compressed. Stability 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 shaft seal 2 shaft 3 housing 10 first seal 11 sleeve 12, 22, 33, 42 cylindrical portion 13, 23, 24, 31, 41 flange portion 15, 25, 55, 71 seal body portion 20 second seal 21 reinforcement Ring 23a Caulking portion 26, 27, 28, 29, 56, 57, 65 Seal lip 26a Garter spring 30 First protective ring 32, 43 Outer peripheral portion 40 Second protective ring 50 Third seal 60 Dust seal 70 Fourth seal 72 Ring 73 Lip shape 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 first protective ring and a second protective ring fixed to the reinforcing ring and provided on the atmosphere side with a predetermined interval in the axial direction from the flange portion;
A third seal provided with a third seal main body that adheres to the flange and slides on the first protective ring;
A fourth seal provided with a fourth seal body portion made of resin that is sandwiched between the first protective ring and the second protective ring and slides in surface contact with the shaft;
A seal with a shaft characterized by comprising:   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 fourth seal main body portion and the cylindrical portion of the second protective ring. Seal with shaft to be used.

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