JP2008170009A - Oil seal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To attain stabilization of sealing performance for a long period of time while attaining reduction of slide resistance and suppression of wearing in an oil seal. <P>SOLUTION: The oil seal 1 has a conical part 6 comprising an elastic body 3 obliquely extending to one side in an axial direction on an inner peripheral portion of an annular core metal 2. In the state that a shaft body 11 is penetrated through an inner periphery, a spring ring 10 is attached to an outer periphery of the conical part 6, and the conical part 6 is deflected in an arch-like shape to be contacted with the shaft body 11 making a main lip 8 and a sub-lip 9 provided on an inner peripheral surface of the conical part 6 as fulcrums respectively by the fastening force. In the state, not only the main lip 8 and the sub-lip 9 of the conical part 6 but also an area at a base end side of the conical part 6 are brought into contact with an outer peripheral surface of the shaft body 11. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an oil seal. This oil seal is suitably used, for example, particularly on the roll end side of the transport segment roll of a continuous casting machine.

  Conventionally, a transport system in a continuous casting machine has a configuration in which a plurality of segment rolls are arranged side by side in the transport direction between two parallel rails extending in the transport direction, and each segment roll has a bearing device at both ends. It is rotatably supported via.

  In this continuous casting machine, in order to cool the cast product to be manufactured, cooling water is applied during the conveying process, so this cooling water enters the inside of the bearing device that supports both ends of each segment roll. It is necessary to prevent it. Therefore, oil seals are usually attached to both ends of the bearing device (see, for example, Patent Document 1).

  A conventional oil seal for the segment roll will be described with reference to FIGS. 3 and 4. FIG. 3 is a longitudinal sectional view of the upper half showing the structure of the support portion of the segment roll, and FIG. 4 is a longitudinal sectional view of the upper half showing the oil seal on the roll end side of the segment roll.

  In the figure, reference numeral 50 denotes a segment roll, and roll necks 51 at both ends of the segment roll 50 are supported by a bearing box 53 via a bearing device 52.

  Oil seals 54 and 55 are disposed on both axial sides of the bearing device 52, respectively. In the drawing, the left oil seal 54 is called the roll end side, and the right oil seal 55 is called the roll neck side, and they are attached to the inner periphery of seal covers 56 and 57 attached to both ends of the bearing box 53, respectively.

  Conventionally, the oil seal 54 on the roll end side, in particular, has a structure in which an elastic body 59 such as synthetic rubber is attached to the outer periphery of a ring 58 having a substantially C-shape in side view as a core as shown in FIG. Yes. A conical portion 60 that extends while reducing the diameter from one axial end side to the other axial end side is provided on the inner peripheral portion of the elastic body 59, and two cross-sections are provided on the distal end side on the inner peripheral surface of the conical portion 60. Substantially triangular lips 61 and 62 are provided, and an auxiliary lip 63 is provided on the proximal end side of the inner peripheral surface of the conical portion 60.

  The inner diameter dimension of the conical portion 60 is set slightly smaller than the outer diameter dimension of the roll neck 51 of the segment roll 50, and the contact pressure of each of the lips 61 to 63 is managed by the interference of this dimension difference.

The conventional oil seal 54 prevents the lubricant such as grease inside the bearing device 52 from leaking to the outside with the main lip 61 and the sub lip 62, and from the outside to the bearing device 52 side with the auxiliary lip 63. The cooling water is prevented from entering.
Japanese Utility Model No. 60-64367 microfilm

  By the way, in the above conventional example, in order to obtain a relatively light contact pressure, the three lips 61 to 63 provided in the conical portion 60 are brought into contact with the roll neck 51 with only interference due to the size difference thereof. However, with this, as the conical portion 60 sags over time, the contact pressure of each of the lips 61 to 63 is lowered, and the followability at the time of rotation of the segment roll 50 is lowered. It is extremely easy to decrease.

  On the other hand, a spring ring called a garter spring (not shown) is attached to the concave portion 64 on the outer periphery of the conical portion 60, and the conical portion 60 may be pressed against the roll neck 51 by the tightening force of the spring ring. In this case, fluctuations in the contact pressure of the lips 61 and 62 can be suppressed regardless of the constriction of the conical portion 60. However, since the main lip 61 and the sub lip 62 are arranged near the center of the spring ring, The contact pressure of the lips 61 and 62 against the roll neck 51 becomes too large. Moreover, each lip 61, 62 has a sharp shape toward the center in the radial direction, and since the contact area with the roll neck 51 is considerably small, a lubricating oil film is difficult to be formed in the contact region. Becomes worse. Accordingly, the sliding resistance is increased and the lips 61 and 62 are easily worn. For this reason, conventionally, the above-described oil seal 54 on the roll end side is not used with a spring ring, and the above-described problems occur.

  Accordingly, an object of the present invention is to achieve long-term stabilization of sealing performance while reducing sliding resistance and suppressing wear in an oil seal.

  The oil seal according to claim 1 of the present invention has a conical portion made of an elastic body extending obliquely in one axial direction at an inner peripheral portion of the annular core metal, and a spring ring is provided in a free end region of the outer peripheral surface of the conical portion. Are fitted on the outer peripheral surface of the conical portion, and a main lip and a sub lip are provided at positions on the free end side of the inner peripheral surface of the conical portion at positions distant from the mounting region of the spring ring in the axial direction. The position where the inner diameter of the inner peripheral surface of the conical portion is maximum between the lip is set on the other side in the axial direction from the mounting region of the spring ring, and in the state where the shaft body is inserted in the inner periphery, The main lip and the sub lip are each supported as a fulcrum by the tightening force of the spring ring, and the conical part is bent like a bow, and not only the main lip and the sub lip but also the region on the proximal end side of the conical part Against The conical portion has a diameter of the conical portion at a position where the inner diameter of the inner peripheral surface of the conical portion is maximized between the main lip and the sub lip on the extended proximal end side of the conical portion. It has the part where radial direction thickness is thinner than directional thickness.

  According to a second aspect of the present invention, in the oil seal according to the second aspect of the present invention, the annular cored bar according to the first aspect has a shape including a cylindrical portion and an annular plate portion extending downward in the radial direction from one axial end of the cylindrical portion. Are arranged on the inner periphery of the cylindrical portion, and an auxiliary lip is provided in the direction opposite to the conical portion from the inner peripheral edge of the annular plate.

  According to a third aspect of the present invention, there is provided an oil seal according to the first aspect of the present invention, wherein the annular cored bar of the first aspect is provided with a cylindrical portion and an annular plate portion extending radially downward from one axial end of the cylindrical portion. An elastic body is attached to a region beyond the outer peripheral surface of the cylindrical portion and the annular plate portion side of the cylindrical portion, and a plurality of annular ridges are provided at a predetermined axial interval in a region corresponding to the outer peripheral surface of the cylindrical portion. The outer peripheral surface of the portion of the elastic body that protrudes from the cylindrical portion is formed into a tapered surface that gradually increases in diameter toward the axial end edge.

  In the present invention, the conical portion is brought into contact with the shaft body by the tightening force of the spring ring. For this reason, even if the conical portion sags with the progress of use, the contact pressure of the main lip and the sub lip provided on the conical portion with respect to the shaft body is less likely to fluctuate over a long period of time.

  In addition, since the formation position of the main lip and the sub lip is set at a position outside the mounting area of the spring ring, the tightening force of the spring ring is not easily transmitted to each lip and is dispersed. Each lip comes into relatively light contact with the shaft. Furthermore, since the contact form between the conical part and the shaft body is not a local contact of only the main lip and the sub lip, but in a surface state, the lubricant enclosed between the lips easily forms a lubricating oil film, The lubricity of each lip is improved. From these things, increase in sliding resistance and progress of wear can be suppressed.

  In addition, in the invention of claim 3, when the oil seal is attached to the case, among the elastic bodies on the outer peripheral side of the cylindrical portion of the annular core metal, the plurality of annular raised portions are elastically deformed. Therefore, the resistance at the time of fitting becomes relatively small, and it becomes possible to easily press-fit by manual operation. In the mounted state, since the plurality of annular ridges are in contact with the inner peripheral surface of the case, the sealing performance of the fitting portion is sufficient.

  According to the first to third aspects of the present invention, the shaft portion of the main lip and the sub lip is brought into contact with the shaft body with the tightening force of the spring ring, regardless of the sag with the use of the cone portion. Can be stably maintained over a long period of time.

  Further, since the main lip and the sub lip are brought into relatively light contact with the shaft body by dispersing the tightening force of the spring ring, sliding resistance can be reduced and wear can be suppressed. Moreover, since a relatively wide area of the conical portion is brought into contact in a surface state rather than a local contact of only the main lip and the sub lip, a lubricating oil film is easily formed at the contact portion, and each lip Lubricity is improved. This also contributes greatly to reducing the above-mentioned sliding resistance and suppressing wear.

  In particular, in the invention of claim 3, when the oil seal is mounted, the entire elastic body on the outer peripheral side of the cylindrical portion of the annular cored bar is not brought into contact with the case, but a plurality of elastic bodies are formed on the elastic body. Since the annular ridges are brought into contact with each other, the resistance when the oil seal is mounted can be made relatively small, and can be easily press-fitted by manual operation.

  Moreover, in the mounted state, the plurality of annular ridges are in contact with the inner peripheral surface of the case, so that the sealing performance of this fitting portion is sufficient.

  Thus, in the oil seal of the present invention, sliding resistance can be reduced and wear can be suppressed, and long-term stabilization of the sealing performance can be achieved.

  The details of the present invention will be described based on the embodiments shown in FIGS.

  1 and 2 relate to one embodiment of the present invention. FIG. 1 is a longitudinal sectional view of an upper half of a single oil seal, and FIG. 2 is a longitudinal sectional view showing a use state of the oil seal.

  In the figure, 1 indicates the entire oil seal, 2 is a metal annular cored bar, and 3 is an elastic body such as synthetic rubber.

  The annular cored bar 2 includes a cylindrical portion 4 and an annular plate portion 5 extending radially downward from one axial end side of the cylindrical portion 4, and is formed in a substantially inverted L shape in cross section.

  The elastic body 3 is attached over the inner peripheral edge of the annular plate portion 5 from the outer peripheral surface of the cylindrical portion 4 of the annular core metal 2. The elastic body 3 on the inner peripheral side of the annular plate portion 5 includes a conical portion 6 that extends while being reduced in diameter from the inner peripheral end of the annular plate portion 5 to one end side in the axial direction, and an axial direction from the inner peripheral end of the annular plate portion 5. And an auxiliary lip 7 that extends while being reduced in diameter toward the end side.

  On the inner peripheral surface of the conical portion 6, a main lip 8 is provided on the distal end side, and a sub lip 9 is provided on the proximal end side of the main lip 8. A spring ring 10 called a so-called garter spring is mounted on the outer periphery of the conical portion 6, and the main lip 8 and the sub lip 9 are attached to the rotating shaft 11 disposed on the inner peripheral side by the tightening force of the spring ring 10. It can be pressed.

  The auxiliary lip 7 is set to have an inner diameter dimension slightly smaller than an outer diameter dimension of the rotating shaft 11, and is brought into contact with the rotating shaft 11 due to the interference of the dimensional difference.

  In the oil seal 1, the main lip 8 and the sub lip 9 prevent the entrance of cooling water from the outside, and the auxiliary lip 7 prevents the lubricant such as grease inside the object to be sealed from leaking to the outside. It has become.

  By the way, the elastic body 3 on the outer peripheral side of the cylindrical portion 4 of the annular core metal 2 is for facilitating the fitting when attaching to the case 12 in the region A corresponding to the free end side on the outer peripheral surface of the cylindrical portion 4. A small-diameter guide surface 13 is provided, and a plurality of (three in the figure) annular ridges 14 arranged in the axial direction are provided in the region B corresponding to the intermediate portion on the outer peripheral surface of the cylindrical portion 4, and the cylindrical portion A projecting portion 15 is provided in a region beyond the four annular plate portions 5. The outer peripheral surface of the projecting portion 15 is formed as a tapered surface 16 whose diameter increases in the projecting direction. That is, the elastic body 3 on the outer peripheral side of the cylindrical portion 4 is not brought into contact with the entire inner peripheral surface of the case 12, but a plurality of the annular raised portions 14 and a part of the tapered surface 16 of the projecting portion 15 are brought into contact with each other. Thus, the fitting margin is set to be relatively small so that the oil seal 1 can be easily press-fitted into the case 12 by hand, and the sealing property of the fitting portion with the case 12 is sufficient. I can do it.

  In this embodiment, the conical portion 6 is designed to have a relatively light contact pressure with respect to the rotating shaft 11 even though the conical portion 6 is fastened by the spring ring 10.

  This is realized by the positional relationship between the main lip 8 and the sub lip 9 and the spring ring 10 in the conical portion 6. In other words, the main lip 8 and the sub lip 9 are respectively provided at positions on the free end side of the inner peripheral surface of the conical portion 6 that are out of the mounting region of the spring ring 10 in the axial direction. The main lip 8 is closer to the distal end side of the cone portion 6 than the axially distal end position of the spring ring 10, and the sub lip 9 is closer to the proximal end side of the cone portion 6 than the axially proximal end position of the spring ring 10. Is arranged. Thus, since both the main lip 8 and the sub lip 9 are separated as much as possible in the axial direction from the center of the tightening load by the spring ring 10, the tightening force of the spring ring 10 is applied to the main lip 8 and the sub lip 9. The main lip 8 and the sub lip 9 are respectively fulcrums and the conical portion 6 is bent in a bow shape. The region on the 6 base end side comes into contact with the outer peripheral surface of the rotating shaft 11. By such a contact form, the contact pressure with respect to the rotating shaft 11 of each lip | rip 8,9 can be made light.

  As described above, when the widest possible range of the inner peripheral surface of the conical portion 6 is brought into contact with the rotating shaft 11, the contact angles of the main lip 8 and the sub lip 9 are preferably set as follows. That is, the outer contact angle α1 of the main lip 8 with respect to the rotating shaft 11 is set to 70 to 80 degrees, preferably 75 degrees, and the inner contact angle β1 is set to 8 to 9 degrees, preferably 8.5 degrees. The outer contact angle α2 of the sub lip 9 with respect to the rotating shaft 11 is set to 40 to 50 degrees, preferably 45 degrees, and the inner contact angle β2 is set to 5 to 7 degrees, preferably 6 degrees. If the main lip 8 and the sub lip 9 have such a shape, they can easily come into contact with the rotating shaft 11 on the surface. For this reason, since the lubricant enclosed between the lips easily forms a lubricating oil film, the lubricity of each of the lips 8 and 9 is improved, and the increase in sliding resistance and the progress of wear can be suppressed. Moreover, since the outer contact angle α1 of the main lip 8 is set to be extremely larger than before, the effect of preventing external water and foreign matter from being caught between the rotary shaft 11 and the tip of the main lip 8 is achieved. Becomes stronger.

  The oil seal 1 described above is used, for example, on the roll end side of the segment roll 50 of the continuous casting machine shown in FIG. In addition, the state which used the oil seal 1 of the said embodiment for the roll end side is shown in FIG.

  The oil seal 1 is press-fitted and fitted in a state where the free end side of the cylindrical portion 4 of the annular core metal 2 is disposed at the back of the case 12 corresponding to the seal cover 56. Conventionally, the oil seal on the roll end side of the segment roll 50 of the continuous casting machine is strongly required to be manually installed. Therefore, the oil seal 1 of this embodiment also accepts the request. It has become.

  That is, first, the small-diameter guide surface 13 of the elastic body 3 on the outer peripheral side of the cylindrical portion 4 of the oil seal 1 is inserted into the opening side of the case 12 and gradually pushed. The annular ridge 14 of the elastic body 3 is crushed during this pushing process, but since the mass to be elastically deformed is small, it can be mounted with relatively little resistance. By the way, in the case of an oil seal as exemplified in the conventional example, the outer peripheral surface of the elastic body is flat and has a required fitting interference, so that the mass to be elastically deformed is large and press-fitted. Although the resistance tends to be excessive, the C-shaped ring is compressed in the radial direction at the time of press-fitting to allow deformation of the elastic body, so that the press-fitting can be performed manually with relatively little resistance. However, in this conventional example, when the annular cored bar is used without using the C-shaped ring, the press-fitting resistance is increased, so that it is difficult to mount manually, and it is necessary to use some kind of jig. In short, in the oil seal 1 according to this embodiment, the shape of the outer peripheral surface of the elastic body 3 on the outer peripheral side is devised so that it can be mounted manually while ensuring the sealing performance of the fitting portion.

  In a state where the oil seal 1 is mounted, not only the main lip 8 and the sub lip 9 of the conical portion 6 but also a wide region including the vicinity of the outer periphery of the segment roll 50 as the rotating shaft 11 is due to the tightening force of the spring ring 10. It will come into contact with the surface. In addition, the contact pressure of the main lip 8 and the sub lip 9 with respect to the segment roll 50 is relatively light. Therefore, reduction of sliding resistance and suppression of wear can be achieved. Although it is inevitable that the conical portion 6 sags over time, the spring ring 10 is forcibly brought into contact with the segment roll 50 so that the relatively light contact state can be maintained over a long period of time. Thus, the sealing performance can be kept stable.

  Further, the auxiliary lip 7 prevents external leakage of the lubricant existing in the bearing device 52.

  As described above, the oil seal 1 of the present invention can be easily attached by manual operation, and can exhibit a sufficient sealing property at a fitting part with the case 12 and a contact part with the rotating shaft 11. ing.

  In addition, this invention is not limited only to the said embodiment, Various application and deformation | transformation can be considered. For example, in the said embodiment, although the example used for the segment roll of a continuous casting machine is given, the use object is not specifically limited.

The longitudinal cross-sectional view of the upper half of the oil seal single body of one Embodiment of this invention Fig. 1 is a vertical sectional view of the upper half showing the usage state of the oil seal of Fig. 1 Vertical section of the upper half showing the support part of the segment roll of a typical continuous casting machine Vertical section of the upper half showing the oil seal on the roll end side of a conventional segment roll

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Oil seal 2 Annular core 3 Elastic body 4 Cylindrical part of annular core metal 5 Annular plate part of annular core metal 6 Conical part of elastic body 7 Auxiliary lip 8 Main lip 9 Sub lip 10 Spring ring

Claims (3)

An oil seal having a conical portion made of an elastic body extending obliquely toward one side in the axial direction on the inner peripheral portion of the annular core bar,
A spring ring is externally fitted to the free end side region of the outer peripheral surface of the conical portion,
A main lip and a sub lip are respectively provided at positions on the free end side of the inner peripheral surface of the conical portion at positions distant from the mounting area of the spring ring in the axial direction.
The position where the inner diameter of the inner peripheral surface of the conical portion is maximum between the main lip and the sub lip is set on the other side in the axial direction from the mounting region of the spring ring,
In the state where the shaft body is inserted in the inner periphery, the main lip and the sub lip become the fulcrum by the tightening force of the spring ring, and the conical portion is bent like a bow. The region on the base end side is also brought into contact with the outer peripheral surface of the shaft body,
The conical portion has a radial thickness that is larger than a radial thickness of the conical portion at a position where the inner diameter of the inner peripheral surface of the conical portion is maximized between the main lip and the sub lip on the extending proximal end side. Has a thin part,
An oil seal characterized by that. The oil seal according to claim 1,
The annular core bar has a cylindrical portion and a shape including an annular plate portion extending downward in the radial direction from one axial end of the cylindrical portion,
The conical portion is disposed on the inner periphery of the cylindrical portion, and an auxiliary lip is provided in the direction opposite to the conical portion from the inner peripheral edge of the annular plate.
An oil seal characterized by that. The oil seal according to claim 1,
The annular core bar has a cylindrical portion and a shape including an annular plate portion extending downward in the radial direction from one axial end of the cylindrical portion,
The elastic body is attached to the outer peripheral surface of the cylindrical portion and the region beyond the cylindrical plate side of the cylindrical portion,
In this elastic body, a plurality of annular ridges are provided in the region corresponding to the outer peripheral surface of the cylindrical portion at a required interval in the axial direction, and the outer peripheral surface of the portion protruding from the cylindrical portion in the elastic body is the end in the axial direction. It is formed on a tapered surface that gradually expands toward the edge side,
An oil seal characterized by that.

Images