JP6534574B2 - Sealing device - Google Patents

Description

  The present invention relates to a sealing device according to sealing technology. The sealing device of the present invention is used for an oil air out lubrication type bearing that supports a roll neck portion in a continuous casting machine.

  Conventionally, as shown in FIG. 5 and FIG. 6, in the bearing 51 for rotatably supporting the roll neck portion 50 in the continuous casting machine, foreign matter of the bearing outside O (cooling water used in the casting process and A sealing device 61 having a structure in which the seal lip 62 is slidably brought into contact with the shaft side circumferential surface 54 so that the resulting scale, etc., (not shown) does not enter the bearing interior I is used.

  Then, in order to lubricate the bearing 51, spray oil is supplied to the inside I of the bearing from the oil / air supply passage 55 provided in the housing 52 together with air (air), and the seal lip 62 is pushed open by the supply pressure. By discharging the oil air of the part to the bearing outside O (the direction of discharge is indicated by the arrow D in FIG. 6), the foreign matter can be reliably prevented from entering the inside I of the bearing and the bearing function is maintained. (See Patent Document 1).

Utility model registration No. 3175048 gazette JP 2005-133885 A

  5 and 6, the control of the pressure (internal pressure) inside the bearing I is performed by the tightening force of the seal lip 62 against the shaft side circumferential surface 54, and the seal lip 62 is tightened to a certain level or more. Power is needed.

  However, it is difficult to maintain the internal pressure stably for a long time due to wear and eccentricity of the seal lip 62 and the shaft side circumferential surface 54, and when the lip inset and lip stiffness are increased to improve the sealing performance, the oil is inversely proportional to this. Since the air dischargeability is lowered, there is a problem that when designing the sealing device 61, it is difficult to achieve both the sealability against external foreign matter and the oil air dischargeability for internal bearing lubrication.

  Further, according to the techniques of FIG. 5 and FIG. 6, the discharge location of the oil air from the seal lip 62 is also affected by the eccentricity etc., and the seal lip 62 has one point where the contact of the seal lip 62 is weakest. There is also a problem that the discharge amount of oil air is insufficient.

  In order to solve the above problems, the invention described in claim 1 of Patent Document 1 has an axial groove 56 crossing the contact area of the seal lip 62 on the shaft side peripheral surface 54, as shown in FIG. A plurality of bearings are provided circumferentially, and oil air is discharged from the bearing inside I to the bearing outside O via the axial groove 56 (the direction of discharge is indicated by the arrow D in FIG. 7).

  However, this invention has room for further improvement in the following points.

  That is, as described above, providing a plurality of axial grooves 56 circumferentially on the shaft-side circumferential surface 54 means adding grooves to parts on the bearing 51 other than the sealing device 61 provided with the seal lip 62. Become. Therefore, it is desirable to solve the above problem only by the configuration of the sealing device 61 without adding grooves to the parts on the bearing 51 other than the sealing device 61.

  In addition, as shown in FIG. 8 as another prior art to the present invention, even with the temperature rise accompanying the operation of the bearing, there is provided a sealing device provided with a sealing device which exhibits stable sealing performance over a long period of time In order to provide a bearing and to achieve this purpose, the sealing device 71 comprises a rubber seal body 72, which comprises a radially extending disc 73 and a disc 73 And the dust lip 75 extending from the inner diameter end of the disc portion 73 to the opposite side of the main lip 74, and axially penetrating the disc portion 73. A technology has been developed in which a slit 76 is provided and a dust lip 75 is provided with a rib 76 (see Patent Document 2).

  However, when the closed space 77 enclosed by the main lip 74, the dust lip 75, and the shaft side circumferential surface 54 becomes negative pressure, the technique of FIG. 8 introduces atmospheric pressure (air) into the space 77. In order to operate the rib 76 as a fulcrum of the insulator, the dust lip 75 is operated to open the sliding portion of the dust lip 75, whereby the atmospheric pressure (air) flows from the bearing outside O into the space 77 (inflow direction is 8 (indicated by arrow E) in FIG.

  Therefore, when the present invention and this technology of FIG. 8 are compared, the air flow directions are opposite to each other (in the present invention, the air flows out from the inside of the bearing to the outside of the bearing, in contrast to the technology of FIG. Then, air flows from the bearing outside O toward the space 77), a protrusion provided on the inner circumferential surface of the seal lip in the present invention, and a rib provided on the inner circumferential surface of the dust lip 75 in the technique of FIG. Compared with 76, its function is different.

  In view of the above points, the present invention can achieve both the sealing property against external foreign matter and the oil air discharge property for internal bearing lubrication with only the configuration of the sealing device, and secure the oil air discharge amount sufficiently. It aims to provide a sealing device that can also be used.

In order to achieve the above object, the present invention adopts the following means.
That is, it is a sealing device which makes the seal lip slidably contact the shaft side peripheral surface so that foreign matter outside the bearing does not intrude into the bearing, wherein the seal lip supplies oil air to the inside of the bearing to carry out the inside of the bearing In the sealing device having a structure in which the oil / air is discharged to the outside of the bearing by being pushed open by the pressure when the pressure of the seal reaches a predetermined value, the bearing inner side of the lip sliding portion on the inner circumferential surface of the seal lip A plurality of projections are provided circumferentially at the positions of the projections, and the projections slidably contact the shaft side peripheral surface, and the contact surface pressure of the lip sliding portion against the shaft side peripheral surface is the projection By setting the portion on the corresponding circumferential portion smaller than the other portions, it is possible to exert the function of specifying the portion to be pushed open by the supply pressure of the oil air to the portion on the circumferential portion. Special To (claim 1).

  In the sealing device of the present invention having the above configuration, a plurality of projections are provided circumferentially on the inner side of the lip sliding portion on the inner peripheral surface of the seal lip on the inner side of the bearing. By slidably contacting the surface, the contact surface pressure of the lip sliding portion with respect to the shaft side circumferential surface is set smaller at one portion on the circumference corresponding to the protrusion portion than at the other portion. Therefore, since the contact pressure is set relatively small at a part of the circumference corresponding to the projection and the contact pressure is set relatively high at the other parts, the same size is applied to these parts. When pressure (internal pressure) is applied, a situation occurs in which only a part of the former on the circumference corresponding to the protrusion is pushed open by the pressure. Therefore, even if the tightening force of the seal lip is set large in order to secure the sealing property against external foreign matter, oil air can be reliably discharged at a portion on the circumference corresponding to the projection, so the external foreign matter It is possible to achieve both the sealability against the above and the oil / air exhaustability for internal bearing lubrication. In addition, since a plurality of protrusions are provided on the circumference and oil air is simultaneously discharged from a plurality of locations on the circumference in accordance with this, it is possible to secure a sufficient oil-air discharge amount.

  The protrusions may be provided such that the protrusions are arranged one by one in the circumferential direction at equal intervals, but a plurality of protrusions may be provided as one set of two protrusions arranged in the circumferential direction. A plurality of sets of protrusions may be arranged at equal intervals in the circumferential direction. In this case, in each set, a valley between two protrusions arranged in the circumferential direction is used as an oil air discharge path. It is possible to use it. In the present invention, as described above, since the circumferential position where the protrusion is provided and the contact surface pressure against the shaft side circumferential surface are set small, the circumferential position of the easily openable portion coincides with the circumference. If one part is provided, oil air will flow in a form that bypasses the protrusion. On the other hand, when the projections are provided in a set of two, the oil air flows in the valley between the projections, and after leaving the valley, if it flows in the axial direction as it is, the oil air contacts the circumferential surface of the shaft Since the surface pressure is set to a small value and thus reaches the easy-to-open area, oil air can flow without bypassing the projection (claim 2).

  As described above, according to the present invention, it is possible to achieve both the sealability against external foreign matter and the oil-air dischargeability for internal bearing lubrication with only the configuration of the sealing device, and also the oil-air discharge amount. It can be secured enough.

Principal part sectional view of the sealing device according to the embodiment of the present invention Sectional drawing which shows the action | operation of the seal lip and protrusion in the same sealing device Explanatory drawing which shows the action | operation of the seal lip and protrusion in the same sealing device Explanatory drawing which shows the oil air discharge location in the same sealing device Principal part sectional view of the bearing which mounts the sealing device Principal part sectional view of sealing device according to prior art Principal part sectional view of sealing device according to prior art Principal part sectional view of sealing device according to prior art

The present invention includes the following embodiments.
(1) Since it is sufficient to make the scale difficult to bite in order to suppress the reduction in the lip interference and the wear, projections are equally distributed circumferentially around the lip tip of the oil seal.
(2) The oil seal used in the oil-air bearing is characterized in that the lip is provided with the equally distributed projections for discharging the supplied air.
(3) The discharge of air is controlled by the height of projections and the equal distribution number through the projections.
(4) With the above-described shape, the number of air discharge points increases, and the amount of air discharge increases, and it becomes difficult to bite the scale into the lip, so it is possible to reduce lip abrasion due to the scale and reduction in margin.
(5) The rubber lip does not have to be considered for the air discharge property, so it is easy to incorporate a design (increasing the interference or increasing the rigidity, etc.) to enhance the prevention of the intrusion of water and scale from the outside. I can expect it.
(6) Even if the above method is adopted, the parts configuration and assembly process are equivalent, and there is no increase in cost.

  Next, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 shows a cross section of an essential part of a sealing device 1 according to an embodiment of the present invention. The sealing device 1 according to the embodiment is used for an oil air out lubrication type bearing 51 that supports a roll neck portion in a continuous casting machine. Further, the sealing device 1 is a sealing device which slidably contacts the seal lips 14 and 34 with the circumferential surface (shaft side circumferential surface) 54 of the shaft 53 so that foreign matter on the bearing exterior O does not intrude into the bearing interior I. The seal lips 14 and 34 supply oil air (not shown) to the bearing inside I and are pushed open by the pressure when the pressure inside the bearing I reaches a predetermined value. It is designed to discharge to O. The shaft 53 is a roll shaft in a continuous casting machine, or a component of a shaft or a bearing such as a sleeve mounted on the outer periphery of the roll shaft main body.

  As the entire configuration of the sealing device 1, a first ring (main ring) 11 fitted to the inner periphery of the bearing housing 52 is provided, and a second ring (second ring) 31 fitted to the first ring 11 Is provided.

  The first ring 11 extends radially inward from a cylindrical fitting portion 12 fitted to the inner periphery of the bearing housing 52 and an end portion of one of the fitting portions 12 in the axial direction (side I of the bearing). The flange-like lip holding portion 13 provided and the seal lip 14 held by the lip holding portion 13 are integrally provided. The seal lip 14 is disposed so as to face the bearing outer O side from the base end portion 14a to the tip end portion 14b to seal external foreign matter, and the lip sliding portion 14c set on the inner peripheral portion of the lip tip end 14b It slidably contacts the shaft side circumferential surface 54 over the entire circumference.

  Further, as the component parts, the first ring 11 is formed on a metal ring (core metal) 15 integrally formed with the flange portion 15b integrally formed radially inward from an axial end of the cylindrical portion 15a, and the metal ring 15 An outer peripheral rubber portion which is adhered (crosslinked) to the outer peripheral surface of the cylindrical portion 15a by the rubber elastic body 16 and which is in close contact with the inner peripheral surface of the bearing housing 52. 17, an end rubber portion 18 attached to the end of the cylindrical portion 15a and in close contact with the end face of the bearing housing 52, an inner peripheral rubber portion 19 attached to the inner peripheral surface of the cylindrical portion 15a, and a flange The end face rubber portion 20 attached to the end face of the portion 15b and the seal lip 14 are integrally formed.

  On the other hand, the second ring 31 is a cylindrical fitting portion 32 fitted on the inner periphery of the fitting portion 12 of the first ring 11 and the other end (the bearing outer O side) of the fitting portion 32 in the axial direction A flange-like lip holding portion 33 provided radially inward from the portion and a seal lip 34 held by the lip holding portion 33 are integrally provided. The seal lip 34 is disposed so as to face the bearing outer O side from the base end portion 34a to the tip end portion 34b in order to seal external foreign matter, and the lip sliding portion 34c set on the inner peripheral portion of the lip tip end 34b It slidably contacts the shaft side circumferential surface 54 over the entire circumference.

  Further, the second ring 31 is attached to the metal ring 35 and the metal ring 35 integrally formed with the flange portion 35b integrally directed radially inward from the other axial end of the cylindrical portion 35a as its component parts. And a rubber-like elastic body 36, and the seal lip 34 is formed by the rubber-like elastic body 36.

  The protrusion 21 is provided on the inner peripheral surface of the seal lip 14 of the first ring 11, that is, the cross-sectional substantially wedge shape at a position on the bearing inside I side than the lip sliding portion 14 c in the inner peripheral surface of the seal lip 14 A plurality of projections 21 having the same size (e.g., eight equal intervals) are provided on the circumference. Similarly, the projection 41 is provided on the inner peripheral surface of the seal lip 34 of the second ring 31, that is, at a position closer to the bearing inside I than the lip sliding portion 34c on the inner peripheral surface of the seal lip 34. A plurality of protrusions 41 having a substantially wedge shape in cross section are provided circumferentially in a plurality (for example, eight).

  The protrusions 21 and 41 slidably contact the shaft side circumferential surface 54, and the contact surface pressure of the lip sliding portions 14 c and 34 c with respect to the shaft side circumferential surface 54 corresponds to the circumference corresponding to the protrusions 21 and 41. By setting the upper part (projected part corresponding part) 14d and 34d smaller than the other parts, the function to identify the part which is pushed open by the supply pressure of oil air to the projected corresponding part 14d and 34d is exhibited. . “Corresponding to the protrusions 21 and 41” means that the circumferential positions of the protrusion corresponding portions 14 d and 34 d are the same as the circumferential positions of the protrusions 21 and 41. The contact surface pressure set to the protrusion corresponding portions 14d and 34d may have zero magnitude.

  Further, each of the protrusions 21 and 41 has a pair of two protrusions 21A, 21B, 41A and 41B arranged in the circumferential direction, and the plurality of protrusions 21A, 21B, 41A and 41B are equally distributed on the circumference. (For example, 8 equal parts, and thus 16 protrusions are provided), and oil air is supplied to the bearing inside I and the pressure inside the bearing I reaches a predetermined value. Oil air from the bearing inside I axially straight toward the lip sliding portions 14c and 34c via the valleys 22 and 42 between the two projections 21A, 21B, 41A and 41B arranged in the circumferential direction from the bearing inside I It is set to flow (the direction of flow is indicated by arrow F in FIG. 1).

  In the sealing device 1 configured as described above, the seal lips 14, 34 can initially slide on the shaft side circumferential surface 54 over the entire circumference as shown in FIG. 2 (A). When oil-air is supplied to the bearing interior I and the pressure P in the bearing interior I reaches a predetermined value, as shown in FIG. Only the protrusion corresponding portions 14d and 34d are pushed open and the seal lip sliding portions 14c and 34c are separated from the shaft side circumferential surface 54 only on the protrusions corresponding portions 14d and 34d on the circumference, and the circle A part of the circumferential gap c is formed. Therefore, as shown in FIG. 3, a part of the oil air is discharged from the radial gap c toward the bearing outer side O (the discharge direction is shown by the arrow G in FIG. 3) to blow away the foreign matter h.

  In the sealing device 1 configured as described above, as described above, a plurality of circumferential projections 21 and 41 are provided at positions closer to the bearing inside I than the lip sliding portions 14c and 34c on the inner peripheral surfaces of the sealing lips 14 and 34. The projections 21 and 41 slidably contact the shaft side circumferential surface 54, and the contact surface pressure of the lip sliding portions 14c and 34c with respect to the shaft side circumferential surface 54 is determined by the projection corresponding portions 14d and 34d. By setting the area smaller than the area of the lower part, oil air is supplied to the inside of the bearing I in order to exhibit the function of specifying the parts which can be pushed open by the supply pressure of the oil air to the projection corresponding parts 14d, 34d. When the pressure reaches a predetermined value, the portions other than the protrusion corresponding portions 14d and 34d remain in contact with the shaft side circumferential surface 54, and only the protrusion corresponding portions 14d and 34d are pushed open by the pressure. . Therefore, even if the tightening force of the seal lips 14 and 34 is set large in order to secure the sealing property against the external foreign matter, the oil air can be reliably discharged at the protrusion corresponding portions 14 d and 34 d, so the seal against the external foreign matter It is possible to achieve both oil resistance and oil-air dischargeability for internal bearing lubrication.

  The amount of oil air discharged is the height (rise height from the inner circumferential surface of the lip) and the width (circumferential width), the number of installation (equal number) of the protrusions 21 and 41, and the protrusions 21 and 41 and a seal Adjustment can be performed by changing the distance (axial distance) or the like from the lip sliding portions 14c and 34c.

  In addition, since a plurality of protrusions 21 and 41 are provided on the circumference to simultaneously discharge the oil air from a plurality of locations on the circumference, a sufficient oil-air discharge amount can be secured. 41 are provided in eight equal arrangements (16 pieces), and as shown in FIG. 4, the oil air is discharged simultaneously from the eight protrusion corresponding parts 14d and 34d on the circumference, so the oil air discharge amount is sufficient. It can be secured.

  Further, since the projections 21 and 41 are provided as a set of two projections 21A, 21B, 41A and 41B aligned in the circumferential direction, a portion of the oil air is circumferentially distributed from the inside I of the bearing. It is set to flow toward the lip sliding parts 14c and 34c via the valleys 22 and 42 between two juxtaposed projections 21A, 21B, 41A and 41B, and the flow direction is in the axial direction. It is straight. Therefore, a part of the oil air can reach the lip sliding parts 14c and 34c without bypassing the protrusions 21 and 41, so that the flow of the oil air can be made smooth.

  Moreover, according to the sealing device 1 of the above-mentioned configuration, it is not necessary to provide an axial groove on the shaft side peripheral surface 54, and it is not necessary to add groove processing to parts on the bearing other than the sealing device 1. Therefore, the above-mentioned effect can be acquired only by the composition of sealing device 1.

DESCRIPTION OF SYMBOLS 1 Sealing device 11 1st ring 12, 32 fitting part 13, 33 lip holding part 14, 34 seal lip 14a, 34a lip base end part 14b, 34b lip tip part 14c, 34c lip sliding part 14d, 34d projection part correspondence Part 15, 35 Metal ring 15a, 35a Tubular part 15b, 35b Flange part 16, 36 Rubber like elastic body 17 Outer peripheral rubber part 18 Tip rubber part 19 Inner peripheral rubber part 20 End surface rubber part 21, 21A, 21B, 41, 41A , 41 B Protrusions 22, 42 Valley 31 second ring 52 Bearing housing 53 Rotating shaft 54 Shaft side circumferential surface I Bearing inside O bearing outside

Claims (2)

A sealing device for slidingly contacting a seal lip with an axial side circumferential surface so that foreign matter outside the bearing does not intrude into the bearing, wherein the seal lip supplies oil air to the inside of the bearing to pressure the inside of the bearing In the sealing device of the structure of discharging the oil air to the outside of the bearing by being pushed open by the pressure when the pressure reaches a predetermined value,
A plurality of projections are provided circumferentially at positions on the inner side of the bearing relative to the lip sliding portion on the inner peripheral surface of the seal lip,
The protrusion is slidably in contact with the shaft side circumferential surface, and the contact surface pressure of the lip sliding portion with respect to the shaft side circumferential surface is a circumferential portion corresponding to the protrusion. The sealing device is characterized in that it is set smaller than the portion so as to specify a portion which is pushed and opened by the supply pressure of the oil air to a portion on the circumference. In the sealing device according to claim 1,
The protrusions are provided with a plurality of sets of protrusions, with two protrusions arranged in the circumferential direction as one set.
When the pressure inside the bearing reaches a predetermined value by supplying the oil air inside the bearing, a part of the oil air passes from the inside of the bearing via the valley portion between the two protruding portions arranged in the circumferential direction. And a sealing device characterized in that it flows toward the lip sliding portion.

Images