JP2006214532A - Oil seal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stabilize sealability by a seal lip by correcting the displacement of a cutting part at least at the seal lip in an oil seal having the seal lip and formed in such a structure that is cut at one position on the circumference. <P>SOLUTION: In this oil seal having the seal lip 4 and the cutting par 7, a load increased part 8 in which the spring load of a garter spring 6 fitted to the seal lip 4 is increased partly on the circumference is formed on the garter spring 6, and the oil seal is fitted with the load increased part 8 aligned with the position of the cutting part 7 on the circumference. As the load increased part 8 used is a wire material 6a forming the garter spring 6 with a wire diameter d<SB>2</SB>larger than the other portions of the load increased part 8 or wire materials 6a and 6b forming the garter spring 6 double-wound at the load increased part 8. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an oil seal which is a kind of a sealing device, and more specifically, an oil having a sealing lip that is slidably in close contact with a mating member and having a cutting portion having a structure cut at one place on the circumference. It relates to the seal. The oil seal of the present invention is used, for example, as a wind power generator main shaft seal.

  Conventionally, as an oil seal for a wind power generator main shaft, an oil seal having a structure in which an annular oil seal is cut at one place on the circumference is employed in order to enable periodic repair.

  4 and 5 show an example of the oil seal 1 having this type of cutting structure, and the oil seal 1 is configured as follows.

  That is, as shown in the cross-sectional view of FIG. 4, the oil seal 1 first has a mounting portion 3 made of rubber-like elastic material that is mounted on the mounting portion 23 between the two housings 21 and 22. A seal lip 4 that is slidably in close contact with the peripheral surface of the shaft 24 that is a sliding counterpart is integrally formed on the inner peripheral side of the mounting portion 3. A mounting groove 5 is provided on the outer peripheral surface of the seal lip 4, and a garter spring 6 having a structure in which a coil spring is annularly wound to adjust the surface pressure of the seal lip 4 against the shaft 24 in the mounting groove 5. Is inserted. Further, as shown in FIG. 5A, the oil seal main body 2 including the mounting portion 3 and the seal lip 4 has a cut portion 7 having a structure in which one place on the circumference is cut. As shown in (B), the sealing property of the cutting part 7 is ensured by attaching the cut end faces 7a and 7b of the cutting part 7 to each other when mounting.

  However, since the conventional oil seal 1 has a structure in which the cut end faces 7a and 7b of the cutting portion 7 are merely attached to each other, the end faces 7a and 7b are likely to be misaligned. As a result, the contact state of the seal lip 4 with the shaft 24 becomes unstable, and there is a concern that the sealing performance of the seal lip 4 is lowered.

  As a technique related to the present invention, the applicant of the present application has previously proposed an oil seal spring in which two wires are brought into close contact with each other and spirally wound. The spring is double-wound over the entire circumference and has a configuration different from that of the present invention (Patent Document 1).

Japanese Utility Model Publication No. 2-48675

  In view of the above, the present invention has an oil seal having a seal lip and is cut at one place on the circumference, and at least the deviation of the cut portion in the seal lip can be corrected. An object of the present invention is to provide an oil seal capable of stabilizing the sealing performance by a lip.

  In order to achieve the above object, an oil seal according to claim 1 of the present invention has a seal lip that is slidably in close contact with a mating member and has a cut portion having a structure cut at one place on the circumference. The garter spring has a load increasing portion in which the spring load of the garter spring fitted to the seal lip is increased in a part of the circumference, and the load increasing portion is located at a position on the circumference of the cutting portion. It is characterized by being mounted together.

  The oil seal according to claim 2 of the present invention is the oil seal according to claim 1 described above, wherein the load increasing portion is thicker in wire diameter of the wire material forming the garter spring than other portions in the load increasing portion. It is characterized by using things.

  The oil seal according to claim 3 of the present invention is the oil seal according to claim 1 described above, wherein the load increasing portion uses a wire material forming a garter spring with a double winding at the load increasing portion. It is characterized by.

  Furthermore, the oil seal according to claim 4 of the present invention is an oil seal having a sealing lip that is slidably in close contact with a mating member, and having a cut portion having a structure cut at one place on the circumference. It has a leaf spring for correcting the shift of the cut end face in the portion, and the leaf spring is mounted according to the circumferential position of the cut portion.

  As in the oil seal according to claim 1 of the present invention having the above-described configuration, the garter spring is provided with a load increasing portion in which the spring load of the garter spring fitted to the seal lip is partially increased on the circumference, When this load increasing portion is mounted in accordance with the circumferential position of the cutting portion, it becomes possible to increase the surface pressure against the shaft of the seal lip at the portion where the load increasing portion is mounted, that is, the cutting portion. Therefore, the contact state of the seal lip with respect to the shaft can be stabilized.

  In addition, as means for providing the load increasing portion on a part of the circumference of the garter spring in this way, as described in claim 2, the wire diameter of the wire forming the garter spring is larger than that of other portions in the load increasing portion. It is preferable to use a thicker one or use a double-wound wire rod forming the garter spring at the load increasing portion.

  Further, as in the oil seal according to claim 4 of the present invention having the above-described configuration, a leaf spring for correcting the deviation of the cut end face in the cutting portion is prepared, and this leaf spring is aligned with the circumferential position of the cutting portion. When attached, the displacement of the cut end face can be forcibly corrected, and thus the contact state of the seal lip with the shaft can be stabilized.

  The present invention has the following effects.

  That is, in the oil seal according to the first, second, or third aspect of the present invention having the above-described configuration, the load increasing portion in which the spring load of the garter spring fitted to the seal lip is increased in part on the circumference is provided with the garter. Since it is provided in the spring and this load increasing portion is mounted according to the circumferential position of the cutting portion, the surface pressure with respect to the shaft of the seal lip in the cutting portion to which this load increasing portion is mounted is increased. The deviation of the cut portion in the seal lip can be corrected, and the contact state of the seal lip with the shaft can be stabilized. Therefore, an oil seal that can stabilize the sealing performance by the seal lip can be provided as intended.

  In the oil seal according to claim 4 of the present invention having the above-described configuration, a leaf spring for correcting the deviation of the cut end face in the cutting portion is prepared, and the leaf spring is aligned with the circumferential position of the cutting portion. Since it is mounted, it is possible to forcibly correct the deviation of the cut end face, thereby stabilizing the contact state of the seal lip with the shaft. Therefore, an oil seal capable of stabilizing the sealing performance by the seal lip can be provided as intended.

  The present invention includes the following embodiments.

Related to Claims 1, 2, and 3 ...
Constitution
The load is increased only for a part of the spring to be attached to the lip portion of the oil seal having a structure where one place on the circumference is cut, and it is used according to the position of the cut portion. The following example is given as a technique for increasing the load only in part.
(1) Use a thick wire.
(2) A double-strike structure is adopted.
effect
By using a portion with an increased load provided on a part of the spring as the cutting portion, it becomes possible to increase the surface pressure only at the cutting portion, and the contact state on the lip axis of the cutting portion is stabilized.

Related to claim 4
Constitution
A plate spring is attached to the cut portion of the oil seal having a structure where one place on the circumference is cut, and the displacement of the cut surface is forcibly corrected. The leaf spring is attached only to the portion straddling the cut portion.
effect
By attaching a leaf spring to the cutting part of the oil seal with a structure cut at one place on the circumference, it is possible to forcibly correct the deviation of the cut surface and maintain a more stable sealing performance than the current situation, Built-in workability is also good because it prevents displacement by one-touch mounting of a leaf spring.

  Next, embodiments of the present invention will be described with reference to the drawings. The first embodiment relates to claims 1 and 2, the second embodiment relates to claim 3, and the third embodiment relates to claim 4.

First embodiment ...
FIG. 1 shows an oil seal 1 according to a first embodiment of the present invention. This oil seal 1 has a garter spring (also simply referred to as a spring) 6 provided with a load increasing portion 8 described in FIG. It is characterized by a point. The oil seal 1 is used as an oil seal for a wind power generator main shaft, and is configured as follows.

  That is, first, an oil seal main body 2 integrally formed with a seal lip 4 slidably in close contact with a peripheral surface of a shaft which is a sliding counterpart is provided on the inner peripheral side of the mounting portion 3 to be mounted on the mounting portion of the housing. As shown in FIG. 1 (A), the oil seal main body 2 has a cutting portion 7 having a structure cut at one place on the circumference thereof, and further, as shown in FIG. 1 (B). Further, a garter spring 6 having a structure in which a coil spring is wound in an annular shape for adjusting the surface pressure of the seal lip 4 with respect to the shaft is fitted in the mounting groove 5 (FIG. 2) provided on the outer peripheral surface of the seal lip 4. Has been. The oil seal body 2 is integrally formed of a rubber-like elastic material such as nitrile rubber.

  As described above, when the oil seal 1 having a structure cut at one place on the circumference has a structure in which the cut end faces 7a and 7b of the cut portion 7 are merely attached to each other, the cut end faces 7a and 7b are displaced from each other. It is easy to occur, and it is feared that the displacement reaches the seal lip 4 and the contact state of the seal lip 4 with the shaft becomes unstable. In this embodiment, the following measures are taken against this concern. Yes.

  That is, in the garter spring 6 having a structure in which the coil spring is wound in an annular shape, the spring load for tightening the seal lip 4 is usually uniform over the entire circumference. A load increasing portion 8 increased at a part on the circumference is provided at a part on the circumference of the garter spring 6, and the load increasing portion 8 is aligned with the position on the circumference of the cutting portion 7 to form a seal lip. 4 is fitted on the outer periphery. In FIG. 1 (B), in the annular garter spring 6, a portion having a constant circumferential length L indicated by dots in the figure is defined as the load increasing portion 8, and this load increasing portion. The garter spring 6 is fitted to the seal lip 4 so that 8 is disposed across the cutting portion 7 in the circumferential direction.

  In the load increasing portion 8, the spring load is increased as follows.

That is, the garter spring 6 made of structure wound with the coil spring in an annular, as shown in the comparative example of FIG. 2 (A), the diameter d ₁ of the wire 6a is uniform over the entire circumference where There is usually desirable, particularly in the embodiment, as shown in FIG. 2 (B), set thicker than the wire diameter d ₁ of the wire 6a wire diameter d ₂ of the wire 6a of the load increasing portion 8 at other sites (D ₂ > d ₁ ), whereby the spring load for tightening the seal lip 4 is locally increased in part on the circumference.

Therefore, the load increasing portion 8 in which the spring load is increased in this way is provided on a part of the circumference of the garter spring 6, and the load increasing portion 8 is mounted in accordance with the circumferential position of the cutting portion 7. Then, the surface pressure with respect to the shaft of the seal lip 4 in the cutting portion 7 to which the load increasing portion 8 is attached increases, and as a result, the displacement of the cutting portion 7 in the seal lip 4 is corrected. The contact state with respect to is stabilized. Therefore, according to the intended purpose of the present invention, it is possible to provide the oil seal 1 that can stabilize the sealing performance by the seal lip 4. Incidentally, the wire diameter d ₁ of the wire 6a in the other sites are normal thickness provided with a (conventional general thickness), wire diameter d ₂ of the wire 6a of the load increasing portion 8 is formed thicker than this ing.

Second embodiment ...
The load increasing portion 8 provided on the garter spring 6 in the first embodiment may be as follows.

  That is, in the garter spring 6 having a structure in which the coil spring is wound in an annular shape, as shown in the comparative example of FIG. 2 (A), the wire 6a is usually wound around the entire circumference. However, in this embodiment, particularly, as shown in FIG. 2C, the wire has a double-winding structure indicated by reference numerals 6a and 6b only in the load increasing portion 8, and thereby the seal lip 4 The spring load for tightening is locally increased in part on the circumference. As shown in the drawing, the double winding structure is such that the second wire 6b is wound around the outer periphery of the first wire 6a over the entire circumference, as described in Patent Document 1 above. Alternatively, the two wires 6a and 6b may be in close contact with each other and spirally wound. Incidentally, the wire diameter of the first wire 6a over the entire circumference has a normal thickness (conventional general thickness), and a part of the second wire 6b on the circumference has the same thickness. However, the thickness is not particularly limited. Further, the material of the wire 6b is not particularly limited.

Third embodiment ...
FIG. 3 shows an oil seal 1 according to a third embodiment of the present invention. This oil seal 1 has a leaf spring 9 for correcting the displacement of the cut end faces 7a and 7b in the cut portion 7. FIG. It has characteristics. The oil seal 1 is used as an oil seal for a wind power generator main shaft, and is configured as follows.

  That is, first, an oil seal main body 2 integrally formed with a seal lip 4 slidably in close contact with a peripheral surface of a shaft which is a sliding counterpart is provided on the inner peripheral side of the mounting portion 3 to be mounted on the mounting portion of the housing. The oil seal main body 2 has a cut portion 7 having a structure cut at one place on the circumference thereof, and a mounting lip 5 provided on the outer peripheral surface of the seal lip 4 has a seal lip for the shaft. A garter spring 6 having a structure in which a coil spring is wound in an annular shape for adjusting the surface pressure of 4 is fitted. The oil seal body 2 is integrally formed of a rubber-like elastic material such as nitrile rubber.

  As described above, when the oil seal 1 having a structure cut at one place on the circumference has a structure in which the cut end faces 7a and 7b of the cut portion 7 are merely attached to each other, the cut end faces 7a and 7b are displaced from each other. It is easy to occur, and there is a concern that the displacement reaches the seal lip 4 and the contact state of the seal lip 4 with the shaft becomes unstable. In contrast, in this embodiment, the following measures are taken.

  That is, a plate spring 9 is provided to correct the deviation of the cut end faces 7a and 7b in the cut portion 7, and the plate spring 9 is fitted to the outer periphery of the seal lip 4 in accordance with the circumferential position of the cut portion 7. It is worn. The leaf spring 9 is disposed so as to straddle the cutting portion 7 in the circumferential direction.

  Further, the leaf spring 9 integrally includes a bullet portion 9 a fitted to the inner peripheral surface of the mounting portion 3 and a bullet portion 9 b fitted to the outer peripheral surface of the seal lip 4. The seal lip 4 is pressed against the peripheral surface of the shaft by a spring load caused by a spring action to open an opening angle of the “<” shape.

  Therefore, when the leaf spring 9 that presses the seal lip 4 against the circumferential surface of the shaft is mounted in accordance with the circumferential position of the cutting portion 7 in this way, the displacement of the cutting end surfaces 7a and 7b of the cutting portion 7 is forced. This corrects and stabilizes the contact state of the seal lip 4 with the shaft. Therefore, according to the intended purpose of the present invention, it is possible to provide the oil seal 1 that can stabilize the sealing performance by the seal lip 4.

  In addition, since the work of assembling the leaf spring 9 having a cross-section “<” shape between the seal lip 4 and the mounting portion 3 can be performed with one touch, the workability of assembling is good.

1A and 1B are views showing an oil seal according to a first embodiment of the present invention, in which FIG. 1A is a front view showing a single state of the oil seal body, and FIG. 1B is a garter spring fitted to the oil seal body. Front view showing the condition FIG. 2A is a diagram illustrating a structure of a garter spring, FIG. 2A is an explanatory diagram of a garter spring provided in an oil seal according to a comparative example, and FIG. 2B is a diagram of a garter spring provided in an oil seal according to a first embodiment. FIG. 2C is an explanatory view of a garter spring provided in the oil seal according to the second embodiment. FIGS. 3A and 3B are views showing an oil seal according to a third embodiment of the present invention, in which FIG. 3A is a front view of an essential part of the oil seal, and FIG. 3B is a perspective view of an essential part of the oil seal. Sectional view showing the general structure of an oil seal FIGS. 5A and 5B are views showing an oil seal according to a conventional example, in which FIG. 5A is a front view showing a single state of the oil seal body, and FIG. 5B is a front view showing a state where a garter spring is fitted to the oil seal body. Figure

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Oil seal 2 Oil seal main body 3 Mounting part 4 Seal lip 5 Mounting groove 6 Garter spring 6a, 6b Wire 7 Cutting part 7a, 7b Cutting end face 8 Load increasing part 9 Leaf spring 9a, 9b Bullet piece 21, 22 Housing 23 Mounting part 24 axes

Claims (4)

In the oil seal (1) having a sealing lip (4) slidably in contact with the mating member and having a cutting part (7) having a structure cut at one place on the circumference,
The garter spring (6) has a load increasing portion (8) in which the spring load of the garter spring (6) fitted to the seal lip (4) is increased in part on the circumference, and the load increasing portion The oil seal according to claim 8, wherein the oil seal is mounted in accordance with a circumferential position of the cutting portion (7). The oil seal of claim 1.
The load increasing part (8) is characterized in that the wire diameter (d ₂ ) of the wire (6a) forming the garter spring (6) is thicker than other parts in the load increasing part (8). And oil seal. The oil seal of claim 1.
The load increasing portion (8) is an oil seal characterized in that the wire rods (6a) (6b) forming the garter spring (6) are double wound in the load increasing portion (8). In the oil seal (1) having a sealing lip (4) slidably in contact with the mating member and having a cutting part (7) having a structure cut at one place on the circumference,
It has a leaf spring (9) for correcting the deviation of the cut end faces (7a) and (7b) in the cut portion (7), and the leaf spring (9) is positioned on the circumference of the cut portion (7). An oil seal characterized by being fitted together.

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