JP2016196928A - Sealing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing device which inhibits accumulation of foreign objects in a parallel groove.SOLUTION: A sealing device 1 includes: a reinforcement ring 10; and an elastic body part 20. The elastic body part 20 has a seal lip 21. The seal lip 21 has a lip tip part 24. The lip tip part 24 is defined by an annular sealing side surface 26 and an annular atmosphere side surface 27 which are connected with each other through a lip tip 25. The atmosphere side surface 27 includes: screw projections 30; a parallel groove 31; and discharge grooves 32. The parallel groove 31 extends in parallel to the lip tip 25 so as to form an annular shape with an axis x located at its center. The discharge grooves 32 communicate with the parallel groove 31 and extend from the parallel groove 31 toward a non-sealing object side (the atmosphere side).SELECTED DRAWING: Figure 1

Description

  The present invention relates to a sealing device, and more particularly to a sealing device used for a rotating shaft of an automobile, a general-purpose machine, or the like.

  2. Description of the Related Art Conventionally, in an engine such as a vehicle, a sealing device is used to seal between a rotating shaft and a through hole of a housing through which the rotating shaft is inserted. FIG. 5 is a cross-sectional view taken along the axis for illustrating the schematic structure of an example of a conventional sealing device. As shown in FIG. 5, the conventional sealing device 100 is formed with an elastic body portion 102 made of an elastic body integrally with a metal reinforcing ring 101. A strip 104 is formed. In the seal lip 103, on the side of the object to be sealed such as oil, a lip tip portion 105 having a wedge-shaped cross section convex toward the inner periphery is formed. The lip tip portion 105 is defined by a sealed side surface 106 that is a conical surface on the sealed object side, and an atmospheric side surface 107 that is a conical surface on the non-sealed object side (atmosphere side). Further, in the seal lip 103, a garter spring 108 for urging the lip tip 105 toward the inner periphery is attached to the outer peripheral surface facing the lip tip 105, and the lip tip 105 is attached to the lip tip 105 with respect to the rotation axis. Giving tension.

  In addition, the conventional sealing device has a pump that forms an air flow from the atmosphere side toward the object to be sealed, and pushes back the object to be sealed such as oil leaking to the atmosphere side beyond the lip tip part to the object to be sealed. Some have a plurality of screw projections arranged at equal intervals to exert an action. For example, the sealing device 100 includes a screw protrusion 109 that exerts a pump action on the atmosphere side surface 107, and the screw protrusion 109 includes a parallel screw protrusion 110 extending from the lip tip 105 a of the lip tip portion 105 and a parallel screw protrusion 110 on the atmosphere side. And a boat bottom screw projection 111 that follows. The parallel screw projection 110 extends obliquely with respect to the lip tip 105a, and the cross-sectional shape orthogonal to the extending direction is uniform over the extending direction. Further, the boat bottom screw projection 111 extends in the same direction as the parallel screw projection 110, and has a boat bottom shape whose height and width are maximized in the middle in the extending direction (for example, patents). Reference 1). Even if the wear of the lip tip 105 progresses due to the screw protrusion 109 formed of the parallel screw protrusion 110 and the boat bottom screw protrusion 111, the pumping action by the screw protrusion 109 is maintained.

  In the conventional sealing device 100 as described above, a gap is generated between the dust strip 104 and the rotating shaft due to a reduction in the interference due to wear of the dust strip 104, eccentricity of the rotating shaft, eccentric mounting, and the like. Foreign matter such as muddy water, sand, and dust may enter between the lip tip 105 and the rotating shaft from the atmosphere side through the gap. In this case, the foreign matter is carried to the lip tip 105a side, the foreign matter is caught between the lip tip 105a and the rotation shaft, and a gap is generated between the lip tip 105a and the rotation shaft, so that the sealed object is moved to the atmosphere side. Leakage may occur, and the sealing device 100 needs to be replaced or cleaned.

  For this reason, as shown in FIG. 6, a conventional sealing device includes a sealing device in which a parallel groove 121 extending in parallel with the lip tip 105a is formed on the atmospheric side surface 107 of the lip tip 105. The parallel groove 121 intersects with the screw projection 109 at the connecting portion between the parallel screw projection 110 and the boat bottom screw projection 111 and is recessed from the air side surface 107 between the adjacent screw projections 109, as in the sealing device 120, for example. . Due to the parallel grooves 121, in the sealing device 120, even if foreign matter enters between the lip tip 105 and the rotary shaft from the atmosphere due to the generation of a gap between the rotary shaft and the dust lip 104, the foreign matter is parallel. Since the foreign material enters and stays in the groove 121, the foreign matter is prevented from approaching the lip tip 105a (see, for example, Patent Document 2).

Japanese Patent No. 3278349 Japanese Patent No. 5637172

  In the sealing device 120 having the parallel grooves 121, further intrusion of the foreign matter that has entered into the lip tip 105 a side can be suppressed by the parallel groove 121, but the foreign matter accumulates in the parallel grooves 121. If accumulation of foreign matter in the parallel groove 121 can be suppressed, a foreign matter entry space can be left in the parallel groove 121, and further penetration of the foreign matter that has entered the lip tip 105a side is suppressed. The action of the parallel grooves 121 can be maintained semipermanently.

  For this reason, in the conventional sealing device 120, it has been desired to be able to suppress the accumulation of foreign matters in the parallel grooves 121.

  This invention is made | formed in view of the above-mentioned subject, The objective is to provide the sealing device which can suppress accumulation of the foreign material in a parallel groove | channel.

  In order to achieve the above object, a sealing device according to the present invention comprises an annular reinforcing ring centering on an axis, a seal lip and a dust lip, and is formed of an elastic body attached to the reinforcing ring. An annular elastic body portion centered on the axis, and the sealing lip has an annular sealing side face on the sealing object side and an annular sealing face side on the non-sealing object side connected via a lip tip. A lip tip portion convex toward the inner peripheral side, which is defined by an atmospheric side surface, and the lip tip portion forms a parallel groove and an air flow toward the sealed object side on the atmospheric side surface. A plurality of threaded protrusions and at least one discharge groove, wherein the parallel groove is a groove extending annularly from the air side surface and extending parallel to the tip of the lip; The protrusion is the tip of the lip A protrusion protruding from the air side surface extending obliquely from the lip end, extending beyond the parallel groove from the tip of the lip, and the plurality of screw protrusions arranged in parallel to each other at equal intervals, the discharge groove Is a groove that is recessed from the air side surface and that communicates with the parallel groove and extends from the parallel groove toward the unsealed object.

  In the sealing device according to an aspect of the present invention, the discharge groove extends from the parallel groove toward the unsealed object between the adjacent screw protrusions.

  In the sealing device according to an aspect of the present invention, the discharge groove extends obliquely to the opposite side of the screw protrusion with respect to the lip tip.

  In the sealing device according to one aspect of the present invention, the discharge groove extends from a portion where the screw protrusion and the parallel groove that form an obtuse angle between the adjacent screw protrusion and the lip tip intersect each other. ing.

  In the sealing device according to one aspect of the present invention, the screw protrusion includes a parallel screw protrusion having a uniform cross-sectional shape perpendicular to an extending direction of the screw protrusion, and a height from the atmospheric side surface of the screw protrusion. A boat bottom-shaped boat bottom screw projection that gradually changes along the extending direction, wherein the boat bottom screw projection is connected to the parallel screw projection on the sealing object side of the boat bottom screw projection. doing.

  According to the sealing device according to the present invention, it is possible to suppress the accumulation of foreign matters in the parallel grooves.

It is a fragmentary sectional view in the section which meets an axis line x for showing a schematic structure of a sealing device concerning an embodiment of the invention. It is the elements on larger scale of the sealing device which expands and shows the lip front-end | tip part of the sealing device shown in FIG. FIG. 3 is a view for illustrating the shape of a screw protrusion in the sealing device shown in FIG. 1, and FIG. 3A is an enlarged view of the screw protrusion when the screw protrusion is viewed along a direction extending along the air side surface and orthogonal to the direction. FIG. 3B is a cross-sectional view in a cross section orthogonal to the extending direction of the parallel screw protrusion of the screw protrusion, and FIG. 3C is a cross-sectional view in a cross section orthogonal to the extending direction of the boat bottom screw protrusion of the screw protrusion. is there. It is a figure for illustrating the shape of the discharge groove in the sealing device shown in FIG. 1, and is a cross-sectional view in a cross section orthogonal to the extending direction of the discharge groove. It is sectional drawing in the cross section which follows the axis line for showing the schematic structure of an example of the conventional sealing device. It is sectional drawing in the cross section in alignment with the axis line for showing the schematic structure of another example of the conventional sealing device.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a partial cross-sectional view in a cross section along an axis x for showing a schematic configuration of a sealing device 1 according to an embodiment of the present invention. A sealing device 1 according to an embodiment of the present invention is used for sealing between a rotating shaft and a member having a through hole through which the rotating shaft is inserted in an automobile, a general-purpose machine, or the like. In order to seal between the crankshaft and the front cover. Hereinafter, for convenience of explanation, the direction of the arrow a (see FIG. 1) in the direction of the axis x is the outside, and the direction of the arrow b (see FIG. 1) in the direction of the axis x is the inside. More specifically, the outer side is the side of the non-sealing object, and is the atmosphere side that prevents the sealing object from being present, and the inner side is the side of the sealing object and is a sealing object such as oil. It is the side facing. Further, in a direction perpendicular to the axis x (hereinafter also referred to as “radial direction”), the direction away from the axis x (the direction of arrow c in FIG. 1) is the outer peripheral side, and the direction approaching the axis x (the arrow d in FIG. 1). Direction) is the inner circumference.

  As shown in FIG. 1, the sealing device 1 includes an annular metal reinforcing ring 10 centered on the axis x, and an elastic body portion 20 made of an annular elastic body centered on the axis x. The elastic body portion 20 is integrally attached to the reinforcing ring 10. Examples of the metal material of the reinforcing ring 10 include stainless steel and SPCC (cold rolled steel). Examples of the elastic body of the elastic body portion 20 include various rubber materials. Examples of the various rubber materials include synthetic rubbers such as nitrile rubber (NBR), hydrogenated nitrile rubber (H-NBR), acrylic rubber (ACM), and fluorine rubber (FKM).

  The reinforcing ring 10 is manufactured by, for example, pressing or forging, and the elastic body portion 20 is formed by cross-linking (vulcanization) molding using a molding die. At the time of this cross-linking molding, the reinforcing ring 10 is disposed in the mold, the elastic body portion 20 is bonded to the reinforcing ring 10 by cross-linking adhesion, and the elastic body portion 20 is formed integrally with the reinforcing ring 10. The

  For example, as shown in FIG. 1, the reinforcing ring 10 has a substantially L-shaped cross section, a cylindrical portion 11 that is a cylindrical portion extending in the axis x direction, and an outer end portion of the cylindrical portion 11. And a flange portion 12 that is a hollow disk-shaped portion that expands toward the inner peripheral side.

  The elastic body portion 20 is attached to the reinforcing ring 10, and in the present embodiment, the elastic body portion 20 is formed integrally with the reinforcing ring 10 so as to cover the reinforcing ring 10 from the outside and the outer peripheral side. The elastic body portion 20 includes a seal lip 21, a dust lip 22, and a lip waist portion 23. As shown in FIG. 1, the lip waist portion 23 is a portion of the elastic body portion 20 that is located in the vicinity of the end portion on the inner peripheral side of the flange portion 12 of the reinforcing ring 10, and the seal lip 21 extends from the lip waist portion 23. It is a portion extending inward and is disposed to face the cylindrical portion 11 of the reinforcing ring 10. The dust lip 22 extends outward from the lip waist 23 toward the axis x.

  The seal lip 21 has a wedge-shaped annular lip front end portion 24 having a cross-sectional shape along the axis x (hereinafter also referred to as a cross-sectional shape) convex toward the inner peripheral side at the inner end. . The lip tip 24 is connected via a lip tip 25 to an annular sealing side 26 on the sealed object side (inner side) and an annular atmospheric side surface 27 on the non-sealed object side (outer side or atmospheric side). It is defined by. The sealing side surface 26 is a conical tapered surface that increases in diameter toward the inner side in the axis x direction, and the atmospheric side surface 27 increases in a conical surface taper that increases in diameter toward the outer side in the axis x direction. Surface. The sealing side surface 26 and the atmospheric side surface 27 intersect with each other on the small diameter side, and a lip tip 25 is formed at the intersecting portion. The lip tip 25 draws a circle centered on the axis x on a plane orthogonal to the axis x, and is located on the innermost peripheral side of the lip tip 24. The lip tip 24 is formed so that, in use, the lip tip 25 and the vicinity thereof are in close contact with the outer peripheral surface of a rotating shaft (not shown) so that the rotating shaft is inserted. It is designed to seal.

  Further, a garter spring 28 is fitted on the outer peripheral portion side of the seal lip 21 so as to face the lip tip portion 24, and the garter spring 28 has a lip tip portion 24 of the seal lip 21 in the inner circumference in the radial direction. The lip tip 24 is biased to the side to give a predetermined amount of pressing force to the rotating shaft.

  The dust lip 22 is a portion extending from the lip waist 23 and extends in the direction of the outer side and the inner peripheral side. The dust lip 22 prevents entry of foreign matter such as muddy water, sand, and dust in the direction of the lip tip 24 in use.

  The elastic body portion 20 includes a fitting portion 29. The fitting portion 29 covers the flange portion 12 of the reinforcing ring 10 from the outside and covers the cylindrical portion 11 of the reinforcing ring 10 from the outer peripheral side. The fitting portion 29 is compressed in the radial direction between the through hole and the cylindrical portion 11 of the reinforcing ring 10 when the sealing device 1 is press-fitted into a through hole of a member (not shown) through which the rotation shaft is inserted. The thickness in the radial direction is set so that a predetermined amount of fitting force, which is a force directed outward in the radial direction, is generated.

  The lip tip 24 of the sealing device 1 includes a plurality of screw projections 30, parallel grooves 31, and at least one discharge groove 32 on the atmospheric side surface 27. The plurality of screw protrusions 30 are provided so as to be able to form an airflow toward the object to be sealed (inner side). The parallel grooves 31 and the discharge grooves 32 are configured so that foreign matters such as muddy water, sand, and dust can 25 is provided to suppress the proximity to 25. FIG. 2 is a partially enlarged view of the sealing device 1 showing the lip tip 24 of the sealing device 1 in an enlarged manner.

  As shown in FIG. 2, the screw protrusion 30 is a protrusion that protrudes from the atmospheric side surface 27 toward the inner peripheral side, and extends obliquely with respect to the lip tip 25 spirally on the atmospheric side surface 27. Further, the plurality of screw protrusions 30 are arranged at equal intervals w in the circumferential direction on the atmospheric air side surface 27, and as will be described later, from the lip tip 25 over the parallel groove 31 to the atmospheric side. It extends. The screw protrusion 30 is inclined on the atmosphere side surface 27 in the direction opposite to the sliding direction of the rotating shaft (the direction of the arrow R in FIG. 2) with respect to the lip tip 25, and the atmosphere side is accompanied by the rotation of the rotating shaft. It has a shape that can generate a pumping action by generating an air flow from the (outside) toward the sealed object side (inside). That is, the sealing device 1 is for right rotation, and the rotation shaft rotates right as viewed from the outside to the inside. The sealing device according to the embodiment of the present invention is not limited to the one for the rotating shaft that rotates to the right, but may have a structure for the rotating shaft that rotates to the left.

  Specifically, as shown in FIG. 2, the screw protrusion 30 includes a parallel screw protrusion 33, which is a portion of a protrusion having a uniform cross-sectional shape orthogonal to the extending direction of the screw protrusion 30, and a height from the atmospheric side surface 27. And a boat bottom screw projection 34 which is a portion projecting in a boat bottom shape that gradually changes along the extending direction of the screw projection 30.

  FIG. 3 is a view for illustrating the shape of the screw protrusion 30, and FIG. 3A is an enlarged view of the screw protrusion 30 when the screw protrusion 30 is viewed along the direction extending in the atmosphere side surface 27 and perpendicular to the direction. 3B is a cross-sectional view in a cross section orthogonal to the extending direction of the parallel screw protrusion 33 of the screw protrusion 30, and FIG. 3C is orthogonal to the extending direction of the boat bottom screw protrusion 34 of the screw protrusion 30. It is sectional drawing in a cross section.

  As shown in FIG. 3A, in the screw protrusion 30, the parallel screw protrusion 33 is a protrusion portion extending from the lip tip 25 toward the atmosphere side, and the height h1 from the atmosphere side surface 27 extends in the extending direction. It is uniform. Further, the parallel screw protrusion 33 has a uniform cross-sectional shape in the cross-section orthogonal to the extending direction, and the cross-sectional shape is not particularly limited, and is, for example, rectangular, substantially rectangular, triangular, or It is an approximate triangle. In the present embodiment, as shown in FIG. 3B, the cross-sectional shape in the cross section orthogonal to the extending direction of the parallel screw protrusions 33 is a triangle, and the tip is provided on the inner peripheral side.

  As shown in FIG. 3A, in the screw projection 30, the boat bottom screw projection 34 is a projection portion extending from the end of the parallel screw projection 33 on the atmosphere side toward the atmosphere side. Is not uniform over the extending direction but gradually changes. Specifically, the height of the boat bottom screw projection 34 from the atmospheric side surface 27 is such that the height h1 of the parallel screw projection 33 is equal to the height h1 of the connection screw 35 where the boat bottom screw projection 34 is connected to the parallel screw projection 33. And gradually increases toward the atmosphere side, and becomes a height h2 at a predetermined position p1 from the connection portion 35 toward the atmosphere side, which is the maximum height. Then, the height from the atmospheric side surface 27 of the boat bottom screw projection 34 gradually decreases from the height h2 toward the atmospheric side from the position p1, and a predetermined position from the connecting portion 35 toward the atmospheric side. It becomes zero at p2. Further, the boat bottom screw projection 34 has a cross-sectional shape similar to the extending direction in a cross section orthogonal to the extending direction, and the area of the cross-sectional shape gradually increases from the connecting portion 35 toward the atmosphere side. , And becomes maximum at the position p1, and gradually decreases from the position p1 toward the atmosphere side. The cross-sectional shape in the cross section orthogonal to the extending direction of the boat bottom screw protrusion 34 is not particularly limited, and is, for example, a rectangle, a substantially rectangular shape, a triangular shape, or a substantially triangular shape. In the present embodiment, as shown in FIG. 3C, the cross-sectional shape in the cross section orthogonal to the extending direction of the boat bottom screw projection 34 is a triangle, and has a sharp tip on the inner peripheral side. Thus, the boat bottom screw projection 34 is a boat-bottomed projection.

  Thus, in the screw protrusion 30, the boat bottom screw protrusion 34 following the parallel screw protrusion 33 on the atmosphere side gradually increases from the connection portion 35 to the position p1 toward the atmosphere side, and then gradually decreases from the position p1. Since it has a boat bottom shape, even when the lip tip 24 is worn and the parallel screw projection 33 is worn away, the boat bottom screw projection 34 is in contact with the rotating shaft and maintains the pump action. can do.

  As shown in FIG. 2, the parallel groove 31 is a groove that is recessed from the atmospheric side surface 27 to the outer peripheral side and extends in an annular shape around the axis line x on the atmospheric side surface 27. The parallel groove 31 extends parallel to the lip tip 25. The cross-sectional shape in the cross section orthogonal to the extending direction of the parallel grooves 31 is not particularly limited, and is, for example, a rectangle, a substantially rectangular shape, a triangular shape, or a substantially triangular shape.

  Further, as shown in FIG. 3A, the parallel groove 31 passes on the atmospheric side surface 27 so as to pass through the position of the connection portion 35 where the parallel screw projection 33 and the boat bottom screw projection 34 are connected to each other in the screw projection 30. It extends. That is, the parallel groove 31 extends to the atmospheric side surface 27 so as to intersect with the screw projection 30 at the connection portion (connection portion 35) between the parallel screw projection 33 and the boat bottom screw projection 34.

  As shown in FIG. 2, the discharge groove 32 is recessed from the atmospheric side surface 27, communicates with the parallel groove 31, and extends from the parallel groove 31 toward the unsealed object side (atmosphere side). It is the groove | channel formed in. Moreover, the cross-sectional shape in the cross section orthogonal to the extending direction of the discharge groove 32 is not particularly limited, and is, for example, a rectangle, a substantially rectangular shape, a triangular shape, or a substantially triangular shape. The sealing device 1 according to the present embodiment has a plurality of discharge grooves 32, and each discharge groove 32 is provided between adjacent screw protrusions 30.

  More specifically, the discharge groove 32 is directed in a direction perpendicular to the lip tip 25 or in a direction opposite to the direction in which the screw protrusion 30 is inclined with respect to the lip tip 25 from the direction perpendicular to the lip tip 25. It extends to. In the present embodiment, as shown in FIG. 2, the discharge groove 32 is inclined with respect to the lip tip 25 in a direction opposite to the direction in which the screw protrusion 30 is inclined with respect to the lip tip 25. Further, the discharge groove 32 is formed between the screw protrusions 30 adjacent to each other on the air side surface 27, and of the two screw protrusions 30, the screw protrusion 30 (sliding of the rotating shaft) forms an obtuse angle with the lip tip 25. The screw protrusion 30 on the opposite side of the direction R) extends from a portion where the parallel groove 31 intersects (intersection 36). The discharge groove 32 extends on the atmosphere side surface 27 to the end of the atmosphere side surface 27 on the atmosphere side. Moreover, as shown in FIG. 4, the cross-sectional shape in the cross section orthogonal to the extension direction of the discharge groove 32 is a triangle.

  As described above, the discharge groove 32 connects the parallel groove 31 to a space on the atmosphere side with respect to the atmosphere side surface 27 in each space between the screw protrusions 30 adjacent to each other on the atmosphere side surface 27. In addition, the discharge groove | channel 32 is not provided in all between the mutually adjacent screw projections 30, and may be provided in any one or every other. The discharge groove 32 preferably extends in a direction perpendicular to the lip tip 25. Further, the connection position of the discharge groove 32 with the parallel groove 31 is not limited to the intersection 36.

  Hereinafter, the operation of the discharge groove 32 and the parallel groove 31 will be described.

  A gap is generated between the dust lip 22 and the rotary shaft due to a reduction in the interference of the dust lip 22 due to wear of the dust lip 22, eccentricity of the rotary shaft, eccentricity with respect to the rotary shaft when the sealing device 1 is attached, etc. Foreign matter may enter between the lip tip 24 and the rotating shaft from the atmosphere side through this gap. Even when the foreign matter has entered in this way, as described above, the parallel groove 31 has a groove extending between the adjacent screw protrusions 30 at a position away from the lip tip 25 to the atmosphere side on the atmosphere side surface 27. Therefore, when the foreign matter that has entered approaches the lip tip 25 further, the foreign matter enters the parallel groove 31. For this reason, it can suppress that a foreign material passes the parallel groove | channel 31, and approaches the lip tip 25, a foreign material bites between the lip tip 25 and the rotating shaft, and a gap is generated between the lip tip 25 and the rotating shaft. Thus, leakage of the sealing object to the atmosphere side is suppressed.

  As described above, the foreign matter that has entered enters the parallel groove 31, and the foreign matter is accumulated in the parallel groove 31. As the foreign matter continues to enter, the parallel groove 31 is eventually filled with the foreign matter, and the foreign matter is accumulated on the air side surface 27 or approaches the lip tip 25. As the foreign matter accumulates on the air side surface 27, the accumulated foreign matter interferes with the rotation shaft and lifts the lip tip 24 from the rotation shaft, and a gap is generated between the lip tip 25 and the rotation shaft. Leakage of sealed objects occurs. On the other hand, when the foreign matter approaches the lip tip 25, as described above, the foreign matter is caught between the lip tip 25 and the rotary shaft, and a gap is generated between the lip tip 25 and the rotary shaft, thereby sealing the lip tip 25. The object leaks to the atmosphere side.

  Here, in the sealing device 1, the discharge groove 32 connects the parallel groove 31 to a space on the atmosphere side with respect to the atmosphere side surface 27. For this reason, the foreign matter that has entered or accumulated in the parallel groove 31 can move to the atmosphere side from the atmosphere side surface 27 via the discharge groove 32, and the discharge groove 32 removes the foreign matter in the parallel groove 31. It can be discharged to the atmosphere side. Further, when the rotating shaft rotates, the screw protrusion 30 exhibits a pump action, and generates an air flow from the atmosphere side toward the sealed object side. Due to this airflow, a force is generated in the discharge groove 32 in the sliding direction R of the rotating shaft, and the foreign matter in the discharge groove 32 can be moved along the discharge groove 32 by the force of the airflow. The foreign matter can be pressed along the discharge groove 32 by the force of the airflow, and the foreign matter in the parallel groove 31 can be pushed out to the atmosphere side through the discharge groove 32.

  Thus, in the sealing device 1, since the discharge groove 32 communicates with the parallel groove 31, the foreign matter that has entered the parallel groove 31 can be pushed out to the atmosphere side from the lip tip portion 24. Further, the ability of the air flow generated by the pump action produced by the screw protrusion 30 to improve the discharge capability of the foreign matter in the parallel groove 31 by the discharge groove 32 can be improved.

  Further, the discharge groove 32 is connected to the parallel groove 31 at the intersection 36 located on the upstream side of the airflow between the screw protrusions 30 adjacent to each other. For this reason, the force of the airflow can be used more effectively for discharging the foreign matter in the parallel groove 31, and the discharge capability of the foreign matter in the parallel groove 31 by the discharge groove 32 can be further improved.

  As described above, according to the sealing device 1 according to the embodiment of the present invention, the foreign matter that has entered the parallel groove 31 can be discharged to the atmosphere side via the discharge groove 32. Accumulation of foreign matter on the surface can be suppressed.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments of the present invention, and includes all aspects included in the concept and claims of the present invention. In addition, the configurations may be appropriately combined as appropriate so as to achieve at least part of the problems and effects described above. For example, the shape, material, arrangement, size, and the like of each component in the above embodiment can be appropriately changed according to the specific usage mode of the present invention.

  Specifically, as long as it has the discharge groove 32 as described above, the reinforcing ring 10 and the elastic body portion 20 may have other forms. The discharge groove 32 extends the atmosphere side surface 27 over the entire area between the parallel groove 31 and the end on the atmosphere side. However, the discharge groove 32 moves the atmosphere side surface 27 from the parallel groove 31 to the atmosphere side. The air side surface 27 may extend partway. Even in this case, the foreign matter can be kept away from the lip tip 25.

  Further, the sealing device 1 according to the present embodiment is applied to an automobile engine, but the application target of the sealing device according to the present invention is not limited to this, and other vehicles, general-purpose machines, The present invention is applicable to all configurations that can utilize the effects of the present invention, such as a rotating shaft of an industrial machine or the like.

1, 100, 120 Sealing device 10, 101 Reinforcement ring 11 Cylindrical part 12 Flange part 20, 102 Elastic body part 21, 103 Seal lip 22, 104 Dustrip 23 Lip waist part 24, 105 Lip tip part 25, 105a Lip tip 26, 106 Sealing side surface 27, 107 Atmospheric side surface 28, 108 Garter spring 29 Fitting portion 30, 109 Screw projection 31, 121 Parallel groove 32 Discharge groove 33, 110 Parallel screw projection 34, 111 Ship bottom screw projection 35 Connection portion 36 Crossing portion h1 , H2 Height p1, p2 Position R Sliding direction w Interval x Axis

Claims (5)

An annular reinforcing ring centered on the axis;
A seal lip and a dust lip, and an annular elastic body centered on the axis formed from an elastic body, attached to the reinforcing ring,
The sealing lip is defined by an annular sealing side face on the side of the sealed object connected via a lip tip and an annular atmospheric side face on the side of the non-sealing object, toward the inner peripheral side. With a convex lip tip,
The lip tip includes a parallel groove, a plurality of screw protrusions that allow airflow toward the sealed object, and at least one discharge groove on the air side surface,
The parallel groove is a groove that is recessed in an annular shape from the atmosphere side surface and extends in parallel to the lip tip,
The screw protrusion is a protrusion protruding from the air side surface extending obliquely with respect to the lip tip, and extends from the lip tip beyond the parallel groove, and the plurality of screw protrusions are equidistant from each other in parallel. Are arranged in
The sealing device according to claim 1, wherein the discharge groove is a groove that is recessed from the air side surface and that extends from the parallel groove toward the non-sealing object side in communication with the parallel groove.   The sealing device according to claim 1, wherein the discharge groove extends from the parallel groove toward the non-sealing object between the screw protrusions adjacent to each other.   The sealing device according to claim 1, wherein the discharge groove extends obliquely to the opposite side of the screw protrusion with respect to the lip tip.   The discharge groove extends from a portion where the screw protrusion and the parallel groove that form an obtuse angle with the lip tip between the adjacent screw protrusions intersect with each other. 4. The sealing device according to any one of items 3. The screw protrusions are parallel screw protrusions having a uniform cross-sectional shape orthogonal to the extending direction of the screw protrusions, and a boat bottom shape whose height from the atmospheric side gradually changes along the extending direction of the screw protrusions. The ship bottom screw projection is connected to the parallel screw projection on the sealing object side of the boat bottom screw projection. The sealing device according to any one of claims 1 to 4.

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