JP7051311B2 - Sealing device - Google Patents

Description

The present invention relates to a sealing device for sealing between a shaft and a hole into which the shaft is inserted.

In vehicles, general-purpose machines, etc., a sealing device has been conventionally used to seal between a shaft and a hole into which the shaft is inserted in order to prevent leakage of a sealed object such as lubricating oil. .. In such a sealing device, the sealing lip is brought into contact with the shaft or an annular member attached to the shaft to seal between the shaft and the sealing device. The contact of this seal lip with the shaft for sealing is also a sliding resistance (torque resistance) with respect to the shaft. In recent years, due to the demand for low fuel consumption of vehicles and the like, the sealing device is required to reduce the sliding resistance with respect to the shaft, and it is possible to reduce the sliding resistance with respect to the shaft while maintaining or improving the sealing performance. The structure is required.

It is conceivable to increase the number of seal lips in order to improve the sealing performance of the sealing device, but increasing the number of seal lips increases the sliding resistance. On the other hand, instead of sealing by increasing the number of seal lips, a groove is provided in the slinger that the seal lip contacts, and the centrifugal force during rotation of the slinger and the pumping action of the groove make it a target to seal oil etc. together with the air on the atmosphere side. Some have improved sealing performance by sending the object to the side to be sealed. Further, the sealed object exuded from the contact portion between the seal lip and the slinger can be returned to the sealed object side by the centrifugal force during the rotation of the slinger and the pumping action of the groove. As described above, a structure for improving the sealing performance of the sealing device by the pumping action of the groove is disclosed (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2-113173

In the conventional sealing device utilizing such a pumping action, it is possible to reduce the sliding resistance while improving the sealing performance. However, in such a sealing device, when the slinger is not rotated, the sealed object may leak to the atmosphere side through the groove of the slinger.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a sealing device capable of reducing sliding resistance during rotation and preventing static leakage of a sealed object during non-rotation. There is something in it.

In order to achieve the above object, the sealing device according to the present invention is a sealing device for sealing an annular gap between a shaft and a hole into which the shaft is inserted, and is fitted into the hole. The sealing device main body is provided with a slinger attached to the shaft, and the sealing device main body is annular around the axis formed by an annular reinforcing ring around the axis and an elastic body attached to the reinforcing ring. The slinger has a flange portion which is an annular portion around the axis extending toward the outer peripheral side, and the elastic body portion has one side in the axial direction. The flange portion extending toward the flange has an end face lip that is an annular lip around the axis that contacts the other side surface in the axial direction, and the other side of the flange portion of the slinger. The surface is provided with radial grooves composed of a plurality of peaks and valleys radially provided so as to reach the outer peripheral edge from the inner peripheral side to the outer peripheral edge at regular intervals in the circumferential direction. The groove is characterized by having a variable pressing force structure in which the pressing force when the lip tip portion of the end face lip is pressed changes from the inner peripheral side toward the outer peripheral side.

In the sealing device according to one aspect of the present invention, in the variable pressing force structure, the height of the mountain portion is constant from the inner peripheral side toward the outer peripheral edge, and the height of the valley portion is inward. It has an inclined shape that approaches the mountain portion from the peripheral side toward the outer peripheral edge, and the depth of the groove formed by the mountain portion and the valley portion is directed from the inner peripheral side toward the outer peripheral edge. It is characterized by becoming shallower with it.

In the sealing device according to one aspect of the present invention, in the variable pressing force structure of the radial groove, the groove depth including the mountain portion and the valley portion is constant, and the mountain portion and the valley portion are on the inner peripheral side. The flange portion becomes thicker toward the outer peripheral edge, and the mountain portion and the valley portion protrude outward as they approach the outer peripheral edge.

In the sealing device according to one aspect of the present invention, the slinger contact portion of the end face lip that contacts the other side surface of the flange portion of the slinger is in contact with the radial groove so as to intersect. It is characterized by.

The sealing device according to one aspect of the present invention is characterized in that the radial groove is formed in a V-shaped cross section.

According to the sealing device according to the present invention, it is possible to realize a sealing device capable of reducing sliding resistance during rotation and preventing static leakage of a sealed object during non-rotation.

It is sectional drawing in the cross section along the axis x for showing the schematic structure of the sealing apparatus which concerns on 1st Embodiment of this invention. It is a partially enlarged cross-sectional view which shows the part of the cross section along the axis of the sealing apparatus which concerns on 1st Embodiment of this invention in an enlarged manner. FIG. 5 is a partially enlarged cross-sectional view of a sealing device in use in which the sealing device according to the first embodiment of the present invention is attached to a housing and a shaft inserted into a shaft hole. FIG. 3 is a perspective view showing a state in which a part of the flange portion of the slinger in the sealing device shown in FIG. 1 is viewed from the outside. It is a top view which shows the structure of the flange part of the slinger which concerns on 1st Embodiment of this invention. It is sectional drawing which shows the cross-sectional structure of the radial groove on the inner peripheral side and the outer peripheral side of the flange part (the outer peripheral side disk part) of the slinger which concerns on 1st Embodiment of this invention. It is a top view which shows the other structural example of the radial groove formed in the flange part of the slinger which concerns on 1st Embodiment of this invention. It is a schematic diagram provided for the explanation of the contact state between the end face lip and the slinger on the inner peripheral side and the outer peripheral side at the time of non-rotation in the sealing device according to the first embodiment of the present invention. It is a schematic diagram provided for the explanation of the contact state between the end face lip and the slinger on the inner peripheral side and the outer peripheral side at the time of rotation in the sealing apparatus which concerns on 1st Embodiment of this invention. FIG. 5 is an enlarged cross-sectional view showing the configuration of a slinger in a used state in which the sealing device according to the second embodiment of the present invention is attached to a housing and a shaft inserted into a shaft hole. It is a top view which shows the structure of the slinger which concerns on the 2nd Embodiment of this invention. It is a partially enlarged plan view which shows the structure of the slinger which concerns on 3rd Embodiment of this invention.

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

<First Embodiment>
FIG. 1 is a cross-sectional view taken along the axis x for showing a schematic configuration of the sealing device 1 according to the first embodiment of the present invention, and FIG. 2 is a cross-sectional view of the first embodiment of the present invention. It is a partially enlarged cross-sectional view which shows by enlarging a part of the cross section along the axis x of the sealing apparatus 1. FIG. FIG. 3 is a partially enlarged cross-sectional view of the sealing device according to the first embodiment of the present invention in a used state in which the sealing device is attached to a housing and a shaft inserted into a shaft hole.

The sealing device 1 according to the present embodiment is a sealing device for sealing an annular gap between a shaft and a hole into which the shaft is inserted, and is formed on the shaft and a housing in a vehicle or a general-purpose machine. This shaft is used to seal between the inserted hole (shaft hole). For example, it is used to seal an annular space between the crankshaft of an engine and a crank hole which is a shaft hole formed in a front cover, a cylinder block, and a crankcase. The object to which the sealing device 1 according to the first embodiment of the present invention is applied is not limited to the above.

Hereinafter, for convenience of explanation, the arrow a (see FIG. 1) direction (one side in the axis direction) is inside in the axis x direction, and the arrow b (see FIG. 1) direction (the other side in the axis direction) in the axis x direction. Is the outside. More specifically, the inside is the side of the space to be sealed (the side of the object to be sealed), the side of the space where the object to be sealed such as lubricating oil is present, and the outside is the side opposite to the inside. .. Further, in the direction perpendicular to the axis x (hereinafter, also referred to as “diameter direction”), the direction away from the axis x (direction of arrow c in FIG. 1) is set as the outer peripheral side, and the direction closer to the axis x (arrow d in FIG. 1). Direction) is the inner circumference side.

As shown in FIG. 1, the sealing device 1 includes a sealing device main body 2 fitted in a hole as a mounting target described later, and a slinger 3 mounted on a shaft as a mounting target described later. The sealing device main body 2 includes an annular reinforcing ring 10 around the axis x, and an annular elastic body portion 20 around the axis x formed from the elastic body attached to the reinforcing ring 10. The slinger 3 has a flange portion 31 which is an annular portion around an axis x extending toward the outer peripheral side (direction of arrow c). The elastic body portion 20 extends toward one side (inside, arrow a direction) in the axis x direction, and is in contact with the surface of the flange portion 31 on the other side (outside, arrow b direction side) in the axis direction x. It has an end face lip 21 which is an annular lip around x.

A plurality of radial grooves 33, which will be described later, are provided on the other side (outside) surface of the flange portion 31 of the slinger 3 in the circumferential direction.

Hereinafter, each configuration of the sealing device main body 2 and the slinger 3 of the sealing device 1 will be specifically described.

As shown in FIGS. 1 and 2, the reinforcing ring 10 in the sealing device main body 2 is an annular metal member centered on or substantially centered on the axis x, and the sealing device main body 2 is press-fitted into the shaft hole of the housing described later. It is formed so as to be fitted, fitted, and fitted. The reinforcing ring 10 includes, for example, a cylindrical portion 11 which is a tubular portion located on the outer peripheral side, a disk portion 12 which is a hollow disk-shaped portion extending from the outer end portion of the tubular portion 11 to the inner peripheral side, and a disk. The pyramidal ring portion 13, which is a conical cylindrical annular portion extending inward and inwardly from the inner peripheral end of the portion 12, and the inner or inner peripheral end of the pyramidal ring portion 13 to the inner peripheral side. It has a disk portion 14 which is a hollow disk-shaped portion extending in the radial direction and reaching the end on the inner peripheral side of the reinforcing ring 10. More specifically, the tubular portion 11 of the reinforcing ring 10 is located on the outer peripheral side cylindrical portion 11a, which is a cylindrical or substantially cylindrical portion located on the outer peripheral side, and on the outer and inner peripheral sides of the outer peripheral side cylindrical portion 11a. It has an inner peripheral side cylindrical portion 11b which is an extending cylindrical or substantially cylindrical portion, and a connecting portion 11c which is a portion connecting the outer peripheral side cylindrical portion 11a and the inner peripheral side cylindrical portion 11b. When the sealing device main body 2 is fitted into the shaft hole 101 of the housing 100 (FIG. 3) described later, the outer peripheral side cylindrical portion 11a of the tubular portion 11 becomes the axis x of the sealing device main body 2 and the axis of the shaft hole 101. It is fitted into the shaft hole 101 so that the two can be matched. An elastic body portion 20 is attached to the reinforcing ring 10 from substantially the outer peripheral side and the outside, and the elastic body portion 20 is reinforced by the reinforcing ring 10.

As shown in FIGS. 1 and 2, the elastic body portion 20 includes a base portion 25 which is a portion attached to an end portion on the inner peripheral side of the disk portion 14 of the reinforcing ring 10, and a tubular portion 11 of the reinforcing ring 10. It has a gasket portion 26 which is a portion attached from the outer peripheral side, and a rear cover portion 27 which is a portion attached to the reinforcing ring 10 from the outside between the base portion 25 and the gasket portion 26. .. More specifically, as shown in FIG. 2, the gasket portion 26 is attached to the inner peripheral side cylindrical portion 11b of the tubular portion 11 of the reinforcing ring 10. Further, the outer diameter of the gasket portion 26 is larger than the diameter of the inner peripheral surface 101a (see FIG. 3) that defines the shaft hole 101 described later. Therefore, when the sealing device main body 2 is fitted into the shaft hole 101 described later, the gasket portion 26 is compressed in the radial direction between the inner peripheral side cylindrical portion 11b of the reinforcing ring 10 and the shaft hole 101, and the shaft The hole 101 and the inner peripheral side cylindrical portion 11b of the reinforcing ring 10 are sealed. As a result, the space between the sealing device main body 2 and the shaft hole 101 is sealed. The outer diameter of the gasket portion 26 does not have to be larger than the diameter of the inner peripheral surface of the shaft hole 101 over the entire axis x direction, and the outer diameter is partially larger than the diameter of the inner peripheral surface of the shaft hole 101. May also be larger. For example, an annular convex portion whose tip diameter is larger than the diameter of the inner peripheral surface 101a defining the shaft hole 101 may be formed on the outer peripheral surface of the gasket portion 26.

Further, in the elastic body portion 20, the end face lip 21 extends inwardly (in the direction of arrow a) from the substrate portion 25 in an annular shape with the axis x as the center or substantially the center, and the sealing device 1 is desired in the mounting target. The slinger contact portion 22a, which is the tip of the lip, is formed so as to come into contact with the flange portion 31 of the slinger 3 from the outside with a certain tightening allowance in the used state attached to the position. The end face lip 21 has, for example, a conical cylinder shape whose diameter increases inward (in the direction of arrow a) in the axis x direction. That is, as shown in FIGS. 1 and 2, the end face lip 21 extends diagonally with respect to the axis x from the base portion 25 to the inner side and the outer peripheral side in a cross section along the axis x (hereinafter, also simply referred to as a cross section). ing.

Further, the elastic body portion 20 has a dust strip 28 and an intermediate lip 29. The dust strip 28 is a lip extending from the base portion 25 toward the axis x, extending from the base portion 25 in an annular shape with the axis x as the center or substantially the center, and the tip portion in the state of use of the sealing device 1 described later. Is formed so as to come into contact with the slinger 3 from the outer peripheral side with a predetermined tightening allowance. The dust strip 28 has, for example, a conical cylindrical shape whose diameter is reduced toward the outside (direction of arrow b) in the axis x direction. The dust strip 28 is intended to prevent foreign matter such as dust and moisture from entering the inside of the sealing device 1 from the outside, which is the side opposite to the sealing object side, in the used state. The dust strip 28 may be formed so as not to come into contact with the slinger 3 in the state of use of the sealing device 1.

As shown in FIG. 2, the intermediate lip 29 is a lip extending inward from the base portion 25 in a substantially L-shaped cross section, and extends from the base portion 25 in an annular shape with the axis x direction as the center or the substantially center. , An annular recess that opens inward is formed between the substrate portion 25 and the substrate portion 25. The intermediate lip 29 is not in contact with the slinger 3 in the state of use of the sealing device 1. In the intermediate lip 29, when the sealed object has penetrated into the inside beyond the slinger contact portion 22a where the end face lip 21 and the slinger 3 are in contact with each other in the used state, the impregnated sealing object is on the dust strip 28 side. It is formed to prevent it from flowing out to. The intermediate lip 29 may have a conical cylindrical shape whose diameter is reduced inward in the x direction of the axis. The intermediate lip 29 may be formed so that its tip contacts the slinger 3.

As described above, the elastic body portion 20 has an end face lip 21, a base portion 25, a gasket portion 26, a rear cover portion 27, a dust strip 28, and an intermediate lip 29, and each portion is integrated. , The elastic body portion 20 is integrally formed of the same material.

The above-mentioned reinforcing ring 10 is formed of a metal material, and examples of the metal material include stainless steel and SPCC (cold rolled steel). Further, as the elastic body of the elastic body portion 20, for example, there are various rubber materials. Examples of various rubber materials are synthetic rubbers such as nitrile rubber (NBR), hydrogenated nitrile rubber (H-NBR), acrylic rubber (ACM), and fluororubber (FKM).

The reinforcing ring 10 is manufactured by, for example, press working or forging, and the elastic body portion 20 is molded by cross-linking (vulcanization) molding using a molding die. At the time of this cross-linking molding, the reinforcing ring 10 is arranged in the molding die, the elastic body portion 20 is adhered to the reinforcing ring 10 by cross-linking adhesion, and the elastic body portion 20 and the reinforcing ring 10 are integrally molded. Will be done.

The slinger 3 is an annular member attached to a shaft in the state of use of the sealing device 1 described later, and is an annular member having an axis x as a center or a substantially center. The slinger 3 has a substantially L-shaped cross section, and has a tubular portion or a substantially tubular tubular portion extending in the x-axis direction connected to the flange portion 31 and the end portion on the inner peripheral side of the flange portion 31. It has 34 and.

Specifically, the flange portion 31 extends radially from the tubular portion 34 into a hollow disk-shaped or substantially hollow disk-shaped inner peripheral side disk portion 31a and an outer peripheral side of the inner peripheral side disk portion 31a. A hollow disk-shaped or substantially hollow disk-shaped outer peripheral side disk portion 31b extending in the radial direction is connected to an outer peripheral side end portion of the inner peripheral side disk portion 31a and an inner peripheral side end portion of the outer peripheral side disk portion 31b. It has a connection portion 31c. The outer peripheral side disk portion 31b is located outside the inner peripheral side disk portion 31a in the axis x direction. The shape of the flange portion 31 is not limited to the above-mentioned shape, and may be various shapes depending on the application target. For example, the flange portion 31 does not have the inner peripheral side disk portion 31a and the connecting portion 31c, and the outer peripheral side disk portion 31b extends to the tubular portion 34 and is connected to the tubular portion 34, from the tubular portion 34. It may be a hollow disk-shaped or substantially hollow disk-shaped portion extending in the radial direction.

The lip contact portion 32, which is a portion where the slinger 3 contacts the end face lip 21, is located on the outer surface 31d, which is a surface facing the outer side of the outer peripheral side disk portion 31b in the flange portion 31. The outer side surface 31d is preferably a surface along a plane extending in the radial direction.

FIG. 4 is a perspective view showing a state in which a part of the flange portion 31 (particularly the outer peripheral side disk portion 31b) of the slinger 3 in the sealing device 1 shown in FIG. 1 is viewed from the outside. FIG. 5 is a plan view showing the configuration of the flange portion 31 (outer peripheral side disk portion 31b) of the slinger 3 according to the first embodiment of the present invention. FIG. 6 is a cross-sectional view showing a cross-sectional configuration of a radial groove on the inner peripheral side and the outer peripheral side of the flange portion 31 (outer peripheral side disk portion 31b) of the slinger 3 according to the first embodiment of the present invention. As shown in FIGS. 4 to 6, a plurality of radial grooves 33 formed of inwardly recessed recesses are formed on the outer surface 31d of the outer peripheral side disk portion 31b of the flange portion 31. Due to the presence of the plurality of radial grooves 33, when the slinger 3 rotates, the lubricating oil or the like is sealed in the region where the plurality of radial grooves 33 are provided (hereinafter, this is also referred to as a “shake-off region”). It is possible to generate a shake-off action (shake-off effect) in which the object is shaken off to the outer peripheral side by centrifugal force.

On the outer surface 31d of the flange portion 31 (outer peripheral side disk portion 31b), the radial groove 33 has an inner peripheral edge 31n on the inner peripheral side of the lip contact portion 32 and an outer peripheral edge on the outer peripheral side of the lip contact portion 32. It is provided radially so as to reach 31e. In particular, the radial groove 33 extends linearly from the inner peripheral edge 31n to the outer peripheral edge 31e. In this case, since the slinger contact portion 22a of the end face lip 21 is contacted at a position where it crosses and crosses a plurality of radial grooves 33, it is always located in the shake-off region.

Specifically, on the outer surface 31d of the flange portion 31, the inner peripheral edge 31n on the inner peripheral side of the lip contact portion 32 reaches the outer peripheral edge 31e on the outer peripheral side of the lip contact portion 32. , A plurality of mountain portions 33y extending linearly and radially at regular intervals in the circumferential direction are formed. Further, on the outer surface 31d of the flange portion 31, it is located at the center between a plurality of mountain portions 33y adjacent to each other, and in a state of reaching the outer peripheral edge 31e from the inner peripheral edge 31n, a straight line is formed at regular intervals in the circumferential direction. A plurality of valleys 33t extending radially at the target are formed.

In this case, the mountain portion 33y functions as a mountain portion in both one radial groove 33 and the adjacent radial groove 33 adjacent thereto. Further, one valley portion 33t is provided for each radial groove 33. That is, the radial groove 33 is composed of two peaks 33y and one valley 33t. In this case, 12 radial grooves 33 are provided in the circumferential direction. However, the present invention is not limited to this, and the mountain portion 33y of the radial groove 33 may have two mountain portions 33y for each radial groove 33, and the number of the radial grooves 33 may be such that the shaking action is exerted. Depending on the number, it may be more than 12 or less.

Here, the heights of the inner peripheral side and the outer peripheral side of the mountain portion 33y are substantially the same as the outer surface 31d of the flange portion 31 and are constant. Specifically, the mountain portion 33y is formed at the same height from the inner peripheral edge 31n to the outer peripheral edge 31e. Therefore, the mountain portion 33y of the radial groove 33 and the outer surface 31d of the flange portion 31 are flush with each other. However, the height of the mountain portion 33y may be slightly lower or slightly higher than the outer surface 31d of the flange portion 31 as long as it is constant from the inner peripheral edge 31n toward the outer peripheral edge 31e. good.

On the other hand, the heights of the inner peripheral side and the outer peripheral side of the valley portion 33t are changing. The height of the inner peripheral side of the valley portion 33t is formed to be significantly lower than the height of the inner peripheral side of the mountain portion 33y, and the height of the outer peripheral side of the valley portion 33t is higher than the height of the outer peripheral side of the mountain portion 33y. Is also formed slightly lower. Specifically, the height of the valley portion 33t gradually increases from the inner peripheral edge 31n to the outer peripheral edge 31e until the outer peripheral edge 31e is reached from the inner peripheral edge 31n toward the outer peripheral edge 31e. There is. The vicinity of the inner peripheral edge 31n of the valley portion 33t is the lowest, and the vicinity of the outer peripheral edge 31e of the valley portion 33t is the highest.

That is, the height of the valley portion 33t gradually increases from the inner peripheral edge 31n toward the outer peripheral edge 31e, and has an inclination approaching the height of the mountain portion 33y. However, the height of the outer peripheral edge 31e of the valley portion 33t is slightly lower than that of the outer peripheral edge 31e of the mountain portion 33y.

As described above, in the radial groove 33, the height of the mountain portion 33y is constant from the inner peripheral edge 31n on the inner peripheral side toward the outer peripheral edge 31e, and the height of the valley 33t is constant from the inner peripheral edge 31n. It has an inclined shape that approaches the mountain portion 33y toward the outer peripheral edge 31e. That is, the radial groove 33 has a concave shape in which the groove depth gradually becomes shallower from the inner peripheral edge 31n toward the outer peripheral edge 31e. Therefore, in the radial groove 33, the pressing force for pressing the slinger contact portion 22a of the end face lip 21 against the peak portion 33y and the valley portion 33t of the radial groove 33 is directed toward the outer peripheral side of the radial groove 33 rather than the inner peripheral side. It forms a variable pressing force structure that becomes stronger with it.

As shown in FIGS. 6A and 6B, the radial groove 33 has a width W1 between the mountain portions 33y due to two mountain portions 33y adjacent to each other and one valley portion 33t located at the center thereof. It has a substantially V-shaped cross section. Further, when the inner angle forming the V shape of the radial groove 33 is defined as the inner angle α, and the inner angle α1n near the inner peripheral edge 31n and the inner angle α1e near the outer peripheral edge 31e, the inner angle α1n is about 175 degrees. It may be about 178 degrees, and the internal angle α1e may be about 178 degrees to 179.5 degrees. In any case, it is at least 170 degrees or more and less than 180 degrees, and α1n> α1e is satisfied. good. However, the cross-sectional shape of the radial groove 33 is not limited to the V shape, and may be, for example, a substantially U shape.

The mountain portion 33y and the valley portion 33t of the radial groove 33 are axial lines from the inner peripheral side to the outer peripheral side (in a direction perpendicular to the axis x) on the outer surface 31d of the flange portion 31 (outer peripheral side disk portion 31b). It extends radially around x, but is not limited to this. FIG. 7 is a plan view showing another configuration example of the radial groove 33 formed in the flange portion 31 of the slinger 3 according to the first embodiment of the present invention. As shown in FIG. 7 (A), assuming that the radial groove 33 exists parallel to the tangent line (not shown) to the inner peripheral edge 31n of the flange portion 31, the radial groove is formed from the radial groove 33. If the angle of inclination when 33 gradually rises in the direction perpendicular to the tangent line is defined as the inclination angle β, the radial groove 33 linearly heads from the inner peripheral side to the outer peripheral side at an arbitrary inclination angle β. May be formed. However, the case where the inclination angle β is 0 degree is excluded because the radial groove 33 does not extend radially from the inner peripheral side to the outer peripheral side. Here, when the inclination angle β of the radial groove 33 is less than 90 degrees perpendicular to the tangent line, a so-called pumping action occurs in addition to the shaking-off action due to the centrifugal force.

As shown in FIG. 7B, instead of the linear groove 33 extending linearly, a plurality of radial grooves 43 extending in a spiral shape from the inner peripheral side to the outer peripheral side may be used. good. Also in this case, due to the presence of the plurality of radial grooves 43, when the flange portion 31 (outer peripheral side disk portion 31b) of the slinger 3 rotates in the axial rotation direction (counterclockwise direction in the drawing), the plurality of radial grooves 43 are also present. It is possible to generate a pumping action in addition to the shaking-off action in the area where the is provided. The radial groove 43 is not limited to a spiral shape, but may be a curved line such as a circular shape. In this case, since it is considered that the shake-off action and the pump action occur in the region where the plurality of radial grooves 43 are provided, it is also referred to as a shake-off pump region below.

The radial groove 43 swirls in the flange portion 31 (outer peripheral side disk portion 31b) from the inner peripheral edge 31n on the inner peripheral side of the lip contact portion 32 to the outer peripheral edge 31e on the outer peripheral side of the lip contact portion 32. It is provided in a radial pattern so that it can be reached by a curved curve. That is, the radial groove 43 extends in the centripetal direction with respect to the axial rotation direction (counterclockwise direction in the figure). Also in this case, since the slinger contact portion 22a of the end face lip 21 is contacted at a position where it crosses and crosses the plurality of radial grooves 43, it is located in the shake-off pump region.

Specifically, in the radial groove 43, the flange portion 31 (outer peripheral side disk portion 31b) has an inner peripheral edge 31n on the inner peripheral side of the lip contact portion 32 and an outer peripheral side on the outer peripheral side of the lip contact portion 32. In the state of reaching the edge 31e, a plurality of mountain portions 43y extending radially in a curve at regular intervals in the circumferential direction are formed. Further, the outer peripheral side disk portion 31b of the flange portion 31 is located at the center between a plurality of mountain portions 43y adjacent to each other, and reaches the outer peripheral edge 31e from the inner peripheral edge 31n at regular intervals in the circumferential direction. A plurality of valleys 43t extending radially in a curved line are formed. Here, the curvatures of the mountain portion 43y and the valley portion 43t gradually increase at the same ratio from the inner peripheral side to the outer peripheral side, and the groove width of the radial groove 43 expands toward the outer peripheral side rather than the inner peripheral side. ing. However, the present invention is not limited to this, and the groove width of the radial groove 43 may be constant without expanding toward the outer peripheral side rather than the inner peripheral side.

In this case as well, 12 radial grooves 43 are provided in the circumferential direction, but the number is not limited to 12 and more than 12 depending on the degree to which the radial grooves 43 exert the shaking-off action and the pumping action. May be good or less. The radial groove 43 has a substantially V-shaped cross section like the radial groove 33, and the internal angles α1n and α1e thereof are the same as those of the radial groove 33.

Further, in the slinger 3, as shown in FIG. 2, the tubular portion 34 has a cylindrical portion 35 which is a cylindrical or substantially cylindrical portion at least partially, and the cylindrical portion 35 is fitted to a shaft. It is formed so that it can be worn. That is, the inner diameter of the cylindrical portion 35 is smaller than the diameter of the outer peripheral surface of the shaft 102 so that the cylindrical portion 35 can be tightened and fitted to the shaft 102. The slinger 3 is not limited to the one that is fixed by the cylindrical portion 35 being fastened and fitted to the shaft 102, and may be one that is adhered to and fixed to the shaft 102 in the tubular portion 34, and other known fixing. It may be fixed to the shaft 102 by a method. The tubular portion 34 may be entirely formed by the cylindrical portion 35.

The slinger 3 is made of a metal material as a base material, for example, SPCC (cold rolled steel) is used as a base material, and SPCC is treated with a phosphate film to prevent rust. .. As the phosphate film treatment, for example, there is a zinc phosphate film treatment. The slinger 3 with high rust prevention performance can suppress the generation of rust on the lip contact portion 32 of the flange portion 31 which is a sliding portion with respect to the end face lip 21, and prolongs the sealing function and sealing performance of the end face lip 21. Can be maintained. Further, it is possible to suppress the change in the shape of the radial groove 33 due to the occurrence of rust, and it is possible to suppress the reduction of the shake-off effect exerted by the radial groove 33. As the base material of the slinger 3, another metal having excellent rust resistance and rust resistance, such as stainless steel, may be used. Further, the rust preventive treatment of the base material of the slinger 3 may be another treatment such as metal plating.

Next, the operation of the sealing device 1 having the above-mentioned configuration will be described. As shown in FIG. 3, the housing 100 is, for example, an engine front cover or a cylinder block and a crankcase, and the shaft hole 101 is a crank hole formed in the front cover or the cylinder block and the crankcase. Further, the shaft 102 is, for example, a crankshaft.

As shown in FIG. 3, in the state of use of the sealing device 1, the sealing device main body 2 is press-fitted into the shaft hole 101 and fitted into the shaft hole 101, and the slinger 3 is tightly fitted to the shaft 102 and fitted to the shaft 102. It is attached to. More specifically, the outer peripheral side cylindrical portion 11a of the reinforcing ring 10 comes into contact with the inner peripheral surface 101a of the shaft hole 101 to align the axis of the sealing device main body 2 with respect to the shaft hole 101, and the elastic body portion. The gasket portion 26 of 20 is radially compressed between the inner peripheral surface 101a of the shaft hole 101 and the inner peripheral side cylindrical portion 11b of the reinforcing ring 10, and the gasket portion 26 is brought into close contact with the inner peripheral surface 101a of the shaft hole 101. Therefore, the sealing device main body 2 and the shaft hole 101 are sealed. Further, the cylindrical portion 35 of the slinger 3 is press-fitted into the shaft 102, the inner peripheral surface 35a of the cylindrical portion 35 is in close contact with the outer peripheral surface 102a of the shaft 102, and the slinger 3 is fixed to the shaft 102.

In the state of use of the sealing device 1, the end face lip 21 of the elastic body portion 20 is the flange portion 31 (outer peripheral side disk portion 31b) of the slinger 3 at the slinger contact portion 22a which is a portion of the inner peripheral surface 22 on the tip end 21a side. The relative position in the axis x direction between the sealing device main body 2 and the slinger 3 is determined so as to come into contact with the lip contact portion 32 which is a portion of the outer surface 31d of the above. Further, the dust strip 28 is in contact with the tubular portion 34 of the slinger 3 from the outer peripheral side at the tip end side portion. The dust strip 28 is in contact with, for example, the outer peripheral surface 35b of the cylindrical portion 35 of the slinger 3.

As described above, in the state of use of the sealing device 1, the end face lip 21 is slidably in contact with the lip contact portion 32 of the flange portion 31 at the slinger contact portion 22a, and the end face lip 21 and the slinger 3 are in slinger contact. To prevent the sealed object such as lubricating oil from seeping out into the sandwiching space S, which is the space between the flange portion 31 and the end face lip 21 from the sealed object side beyond the contact portion 22a and the lip contact portion 32. There is. Further, in the dust strip 28, the tubular portion 34 of the slinger 3 is slidably in contact with the tubular portion 34 to prevent foreign matter from entering from the outside to the inside.

Further, in the state of use of the sealing device 1, the plurality of radial grooves 33 formed on the outer surface 31d of the flange portion 31 (outer peripheral side disk portion 31b) of the slinger 3 are shaken when the shaft 102 (slinger 3) is rotated. Brings a cutting action. That is, due to the rotation of the slinger 3 (shaft 102), in the sandwiching space S between the flange portion 31 and the end face lip 21, the swinging action of the plurality of radial grooves 33 in the region near the slinger contact portion 22a and the lip contact portion 32. Occurs.

Due to this shake-off action, even when the sealed object seeps out from the sealed object side into the sandwiching space S, the exuded sealed object exceeds the slinger contact portion 22a and the lip contact portion 32 from the sandwiching space S. Is returned to the sealed object side. As described above, the swaying action generated by the plurality of radial grooves 33 formed in the flange portion 31 of the slinger 3 suppresses the exudation of the sealed object into the sandwiching space S.

FIG. 8 is a schematic diagram for explaining the contact state between the end face lip 21 and the slinger 3 on the inner peripheral side and the outer peripheral side in the sealing device 1 according to the first embodiment of the present invention. As shown in FIGS. 8A and 8B, when the end face lip 21 is pressed against the outer surface 31d of the flange portion 31 with a predetermined tightening margin in the sealing device 1 when the slinger 3 is not rotating. The slinger contact portion 22a of the end face lip 21 is elastically deformed so as to follow the shape of the V-shaped cross section formed by the peak portion 33y and the valley portion 33t of the radial groove 33, and a close contact state with the lip contact portion 32 is formed. To.

By the way, in the radial groove 33, the groove depth is deeper on the inner peripheral side and shallower on the outer peripheral side, but when the slinger 3 is not rotated, FIGS. 8A and 8A and ( As shown in B), the slinger contact portion 22a of the end face lip 21 is in close contact with both the inner peripheral side and the outer peripheral side of the mountain portion 33y and the valley portion 33t.

Therefore, when the slinger 3 is not rotated, the slinger contact portion 22a of the end face lip 21 and the lip contact portion 32 of the flange portion 31 are in close contact with each other, so that the object to be sealed seeps out into the sandwiching space S. Can be prevented and static leakage can be suppressed. In particular, the radial groove 33 has a shallower groove on the outer peripheral side than the lip contact portion 32 of the flange portion 31, and the slinger contact portion 22a of the end face lip 21 has a V-shaped cross section of the radial groove 33 than the region on the inner peripheral side. Since it is easy to follow the shape of and adhere to each other, it is possible to improve the effect of static leakage at the time of non-rotation.

Here, due to various other factors such as the tightening allowance of the end face lip 21, the internal angles α1n and α1e of the radial groove 33, and the material of the end face lip 21, the slinger contact portion 22a of the end face lip 21 and the lip contact portion 32 of the flange portion 31 Since the state of close contact with and is changed, it is premised that the conditions for close contact with a predetermined tightening allowance are satisfied.

Therefore, when the slinger 3 is not rotated, the contact surface between the slinger contact portion 22a of the end face lip 21 and the lip contact portion 32 of the flange portion 31 is maintained in close contact with each other. Can be prevented from seeping out into the sandwiched space S, and by extension, the sealed object can be prevented from leaking from the dust strip 28 to the atmosphere side from the narrow space S. That is, in the sealing device 1, the sealing performance at the time of non-rotation can be maintained.

On the other hand, as shown in FIGS. 9A and 9B, in the sealing device 1, when the slinger 3 is rotated (including the idling rotation state), the end face lip is caused by the rotation of the flange portion 31 (outer peripheral side disk portion 31b). The slinger contact portion 22a of 21 cannot follow the shape of the V-shaped cross section of the radial groove 33, and the end face lip 21 is separated in the direction of the arrow on both the inner peripheral side and the outer peripheral side of the mountain portion 33y and the valley portion 33t. It floats up.

However, when the flange portion 31 (outer peripheral side disk portion 31b) is rotated, a shake-off action is performed by the plurality of radial grooves 33, so that the sealed object exuding from the sealed object side into the narrow space S has a shake-off region. It will be returned to the sealed object side by the shaking action of. In this case, since the slinger contact portion 22a of the end face lip 21 is separated from the lip contact portion 32 of the flange portion 31 (outer peripheral side disk portion 31b), the sliding resistance is significantly reduced and the torque is reduced. Can be done. That is, in the sealing device 1, it is possible to realize low torque while maintaining the sealing performance during rotation.

Further, when the slinger 3 is rotated, the peripheral speed of the mountain portion 33y and the valley portion 33t is higher than the peripheral speed of the inner peripheral side, so that the end face lip 21 is formed from the peak portion 33y and the valley portion 33t on the outer peripheral side. Since it floats easily, it is possible to further reduce the torque while maintaining the sealing performance.

As described above, according to the sealing device 1 according to the first embodiment of the present invention, the exudation of the sealed object during rotation is suppressed, the sliding resistance during rotation is reduced, and the sliding resistance during rotation is reduced. It is possible to prevent static leakage of the sealed object during rotation.

<Second embodiment>
Hereinafter, a second embodiment of the present invention will be described. In the second embodiment, as shown in FIG. 10, the radial groove 53 provided in the flange portion 31 of the slinger 3 and the outer peripheral end edge 31e of the flange portion 31 are outward toward the outer peripheral edge 31e. It is characterized by having an outer peripheral side disk portion 31bb provided so as to gradually protrude (protrude).

The flange portion 31 of the slinger 3 according to the second embodiment of the present invention has the same basic function as the flange portion 31 of the slinger 3 according to the first embodiment of the present invention, but has the same basic function as the outer peripheral disk. It has an outer peripheral side disk portion 31bb having a shape different from that of the portion 31b.

Also in this case, due to the presence of the plurality of radial grooves 53, when the slinger 3 (outer peripheral side disk portion 31bb) rotates in the axial rotation direction (counterclockwise direction in the figure), the plurality of radial grooves 53 are provided. It is possible to generate a shake-off action in the shake-off region.

As shown in FIG. 11, in the flange portion 31 (outer peripheral side disk portion 31bb), the radial groove 53 is located on the outer peripheral side of the lip contact portion 32 from the inner peripheral end edge 31n on the inner peripheral side of the lip contact portion 32. It is provided radially so as to reach the outer peripheral edge 31e in a straight line. Also in this case, since the slinger contact portion 22a of the end face lip 21 is contacted at a position where it crosses and crosses the plurality of radial grooves 53, it is located in the shakeout region.

The flange portion 31 (outer peripheral side disk portion 31bb) has an outer inclined surface 31dd that gradually protrudes outward from the inner peripheral edge 31n of the radial groove 53 toward the outer peripheral edge 31e on the outer surface 31d. A radial groove 53 is formed on the outer inclined surface 31dd.

In this case, the thickness t2 of the flange portion 31 (outer peripheral side disk portion 31bb) near the outer peripheral edge 31e is larger than the thickness t1 of the flange portion 31 (outer peripheral side disk portion 31bb) near the inner peripheral edge 31n. It is thick and satisfies the relationship of thickness t2> thickness t1. That is, the thickness of the outer inclined surface 31dd of the flange portion 31 on which the radial groove 53 is formed gradually increases from the inner peripheral edge 31n toward the outer peripheral edge 31e, and has an inclined shape having a predetermined angle. There is.

Specifically, on the outer inclined surface 31dd of the flange portion 31 (outer peripheral side disk portion 31bb), from the inner peripheral end edge 31n on the inner peripheral side of the lip contact portion 32 to the outer periphery on the outer peripheral side of the lip contact portion 32. In the state of reaching the edge 31e, a plurality of mountain portions 53y extending linearly and radially at regular intervals in the circumferential direction are formed. The mountain portion 53y is higher than the outer inclined surface 31dd, and its height remains constant and extends.

Further, the outer inclined surface 31dd of the flange portion 31 (outer peripheral side disk portion 31bb) is located at the center between a plurality of mountain portions 53y adjacent to each other, and reaches the outer peripheral edge 31e from the inner peripheral edge 31n. , A plurality of valley portions 53t extending linearly and radially at regular intervals in the circumferential direction are formed. The valley portion 53t extends at the same height as the outer inclined surface 31dd of the outer peripheral side disk portion 31bb. However, the present invention is not limited to this, and the valley portion 53t may be slightly higher or slightly lower than the outer inclined surface 31dd, and the point is the same from the inner peripheral edge 31n to the outer peripheral edge 31e. It suffices to extend at the same height.

As described above, the radial groove 53 is composed of a plurality of mountain portions 53y and valley portions 53t provided on the outer inclined surface 31dd. That is, the radial groove 53 has a constant groove depth on both the inner peripheral edge 31n side and the outer peripheral edge 31e side, but since it is provided on the outer inclined surface 31dd, the portion on the outer peripheral edge 31e side is provided. It protrudes outward from the portion on the inner peripheral edge 31n side and is in a state of approaching the slinger contact portion 22a of the end face lip 21.

In this case, the mountain portion 53y functions as a mountain portion in both one radial groove 53 and the adjacent radial groove 53 adjacent thereto. Further, one valley portion 53t is provided for each radial groove 53. That is, the radial groove 53 is composed of two mountain portions 53y and one valley portion 53t. In this case, 12 radial grooves 53 are provided in the circumferential direction. However, the present invention is not limited to this, and the mountain portion 53y of the radial groove 53 may have two mountain portions 53y for each radial groove 53, and the number of the radial grooves 53 may be such that the shaking action is exerted. Depending on the number, it may be more than 12 or less.

The radial groove 53 has a cross-sectional shape having a substantially V-shaped cross section due to two mountain portions 53y adjacent to each other and one valley portion 53t located at the center thereof. The internal angle α forming the V-shape of the radial groove 53 may be about 175 degrees to 179.5 degrees, and may be at least 170 degrees or more and less than 180 degrees. However, the cross-sectional shape of the radial groove 53 is not limited to the V shape, and may be, for example, a substantially U shape.

As described above, the radial groove 53 has a constant groove depth from the inner peripheral edge 31n toward the outer peripheral edge 31e, but since it is provided on the outer inclined surface 31dd, the portion on the outer peripheral edge 31e side is inside. It has a concave shape that protrudes outward from the portion on the peripheral edge 31n side and is close to the slinger contact portion 22a of the end face lip 21. Therefore, in the radial groove 53, the pressing force for pressing the slinger contact portion 22a of the end face lip 21 against the mountain portion 53y and the valley portion 53t becomes stronger toward the outer peripheral side than the inner peripheral side of the radial groove 53. It forms a variable pressing force structure.

According to the second embodiment of the present invention, exudation of the sealed object during rotation is suppressed, sliding resistance during rotation is reduced, and static leakage of the sealed object during non-rotation is achieved. Can be prevented.

<Third embodiment>
Next, a third embodiment of the present invention will be described. In the third embodiment, as shown in FIG. 12, the radial groove 53 provided in the flange portion 31 of the slinger 3 in the second embodiment is the same, but the radial groove 53 is the slinger 3. The difference is that the flange portion 31 (outer peripheral side disk portion 31b) is provided on the flat outer surface 31d, and the flange portion 31 (outer peripheral side disk portion 31b) is slightly inclined toward the outside.

In this case, the flange portion 31 (outer peripheral side disk portion 31b) has a constant thickness from the inner peripheral side toward the outer peripheral side, but the outer peripheral side disk portion 31b is slightly inclined toward the outside. There is. For this reason, the portion of the radial groove 53 on the outer peripheral edge 31e side protrudes outward from the portion on the inner peripheral edge 31n side, and is in a state of approaching the slinger contact portion 22a of the end face lip 21.

In this way, the flange portion 31 (outer peripheral side disk portion 31b) gradually inclines outward from the inner peripheral side toward the outer peripheral side, and the outer surface 31d is outward as it goes toward the outer peripheral side rather than the inner peripheral side. As a result, the portion of the radial groove 53 on the outer peripheral edge 31e side protrudes outward from the portion on the inner peripheral edge 31n side, and is in a state of approaching the slinger contact portion 22a of the end face lip 21. ing.

As described above, the radial groove 53 has a constant groove depth from the inner peripheral edge 31n to the outer peripheral edge 31e, but the outer surface 31d protrudes outward as it goes toward the outer peripheral side rather than the inner peripheral side. Therefore, the portion on the outer peripheral edge 31e side protrudes outward from the portion on the inner peripheral edge 31n side, and has a concave shape in a state of approaching the slinger contact portion 22a of the end face lip 21. Therefore, in the radial groove 53 provided in the flange portion 31 (outer peripheral side disk portion 31b) of the slinger 3 inclined in this way, the pressing force for pressing the slinger contact portion 22a of the end face lip 21 against the peak portion 53y and the valley portion 53t. Formes a variable pressing force structure that becomes stronger toward the outer peripheral side of the radial groove 53 than the inner peripheral side.

Therefore, according to the third embodiment of the present invention, the exudation of the sealed object during rotation is suppressed, the sliding resistance during rotation is reduced, and the sealed object during non-rotation is reduced. It is possible to prevent static leakage.

<Other embodiments>
In the first to third embodiments described above, the case where the radial grooves 33 and 53 extending linearly are targeted has been described, but the present invention is not limited to this, and the inner peripheral edge 31n is used. As long as it reaches the outer peripheral edge 31e radially, it may be a radial groove extending in various other shapes such as a wave shape and a zigzag shape.

Further, in the first to third embodiments described above, in the sealing device 1, the elastic body portion 20 has a dust strip 28 and an intermediate lip 29, but the elastic body portion 20 has a data. It may not have the strip 28 and the intermediate lip 29, and may have only one of the dust strip 28 and the intermediate lip 29.

Further, the sealing device 1 according to the first to third embodiments is applied to the crank hole of the engine, but the application target of the sealing device according to the present invention is not limited to this. The present invention is applicable to all configurations that can utilize the effects of the present invention, such as vehicles, general-purpose machines, and industrial machines.

1 ... Sealing device, 2 ... Sealing device body, 3 ... Slinger, 10 ... Reinforcing ring, 11 ... Cylindrical part, 11a ... Outer peripheral side cylindrical part, 11b ... Inner peripheral side cylindrical part, 11c ... Connection part, 12, 14 ... Disk part, 13 ... Cylinder ring part, 20 ... Elastic body part, 21 ... End face lip, 21a ... Tip, 21b ... Root, 22 ... Inner peripheral surface, 22a ... ... Slinger contact part, 25 ... Base part, 26 ... Gasket part, 27 ... Rear cover part, 28 ... Dustrip, 29 ... Intermediate lip, 31 ... Flange part, 31a ... Inner circumference side disk part , 31b ... Outer peripheral disk part, 31c ... Connection part, 31d ... Outer surface, 32 ... Lip contact part, 33, 53 ... Radial groove, 34 ... Cylindrical part, 35 ... Cylindrical part, 35a ... ... Inner peripheral surface, 35b ... Outer peripheral surface, 100 ... Housing, 101 ... Shaft hole, 101a ... Inner peripheral surface, 102 ... Axis, 102a ... Outer peripheral surface, S ... Sandwich space, x ... Axis line ..

Claims (5)

A sealing device for sealing an annular gap between a shaft and a hole into which the shaft is inserted.
The sealing device body fitted in the hole and
Equipped with a slinger attached to the shaft
The sealing device main body has an annular reinforcing ring around the axis and an annular elastic body portion around the axis formed from the elastic body attached to the reinforcing ring.
The slinger has a flange portion which is an annular portion around the axis extending toward the outer peripheral side.
The elastic body portion has an end face lip, which is an annular lip around the axis, extending toward one side in the axial direction and in contact with the surface on the other side in the axial direction on the flange portion.
On the other side surface of the flange portion of the slinger, a plurality of mountain portions and a plurality of mountain portions radially provided so as to reach the outer peripheral edge on the outer peripheral side from the inner peripheral side at regular intervals in the circumferential direction. A radial groove is formed , which is composed of a valley portion and whose groove width is gradually widened from the inner peripheral side of the flange portion toward the outer peripheral edge of the outer peripheral side .
When the end face lip is pressed against the flange portion when the slinger is not rotating, the slinger contact portion of the end face lip is elastically deformed so as to follow the shape of the radial groove, and the slinger contact portion and the radial portion are formed. The groove comes into contact with each other, and a close contact state between the end face lip and the flange portion is formed.
The radial groove has a sealing device having a variable pressing force structure in which the pressing force when the lip tip portion of the end face lip is pressed is changed from the inner peripheral side to the outer peripheral side. .. In the variable pressing force structure, the height of the mountain portion is constant from the inner peripheral side toward the outer peripheral edge, and the height of the valley is constant from the inner peripheral side toward the outer peripheral edge. The present invention is characterized in that it has an inclined shape approaching the mountain portion, and the depth of the groove formed by the mountain portion and the valley portion becomes shallower from the inner peripheral side toward the outer peripheral edge. The sealing device according to 1. In the variable pressing force structure of the radial groove, the groove depth including the mountain portion and the valley portion is constant, and the mountain portion and the valley portion are said to be directed from the inner peripheral side toward the outer peripheral edge. The sealing device according to claim 1, wherein the thickness of the flange portion is increased, and the mountain portion and the valley portion are projected toward the other side in the axial direction as they approach the outer peripheral edge. Any of claims 1 to 3, wherein the slinger contact portion of the end face lip, which is in contact with the other side surface of the flange portion of the slinger, is in contact so as to intersect the radial groove. The sealing device according to the first paragraph. The sealing device according to any one of claims 1 to 4, wherein the radial groove is formed in a V-shaped cross section.

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