JP6443821B2 - Sealing device - Google Patents

Description

  The present invention relates to a sealing device, and more particularly, to a sealing device used for preventing entry of foreign matter such as rainwater and muddy water in a vehicle or the like.

  2. Description of the Related Art In a vehicle, for example, an automobile, a wheel bearing device (hereinafter also referred to as a hub bearing) that rotatably supports wheels is in an environment where it is directly exposed to foreign matter such as rainwater and muddy water. For this reason, conventionally, a sealing device is attached to the wheel bearing device in order to seal the wheel bearing device from the outside. This sealing device is intended to prevent foreign matters such as rainwater and muddy water from entering the wheel bearing device.

  FIG. 8 is a partial cross-sectional view illustrating a schematic configuration of a sealing device (hereinafter also referred to as a hub seal) attached to a conventional wheel bearing device. As shown in FIG. 8, a sealing device 100 as a conventional hub seal is configured to seal an annular space 203 between an outer ring 201 and an inner ring 202 that are relatively rotated coaxially with each other in a wheel bearing device 200. It is press-fitted between the outer ring 201 and the inner ring 202. The wheel bearing device 200 is a rolling bearing, and a rolling element (not shown) is disposed between the outer ring 201 and the inner ring 202 so that the outer ring 201 and the inner ring 202 can rotate relative to each other. The sealing device 100 suppresses foreign matter from entering the space 203.

  As shown in FIG. 8, the sealing device 100 includes an annular sealing device main body 110 fitted inside the outer ring 201 and an annular slinger 120 fitted outside the inner ring 202. The sealing device main body 110 includes an annular reinforcing ring 111 and an elastic body portion 112 made of a rubber material integrally formed so as to cover the reinforcing ring 111. The reinforcing ring 111 has a substantially L-shaped cross section along the axis, and the cylindrical portion on the outer peripheral side of the reinforcing ring 111 is liquid-tightly fitted to the inner peripheral surface of the outer ring 201. Has been. The elastic body portion 112 is formed on the inner peripheral side and the outer side of the reinforcing ring 111, and in the direction (radial direction) from the outer peripheral cylindrical portion 113 and the axial direction from the inner end of the cylindrical portion 113. And a base portion 114 extending. The base portion 114 includes two side lips 115 extending outward in the axial direction and a radial lip 116 extending in the radial direction.

  The slinger is made of metal, and the cross-sectional shape along the axis is substantially L-shaped as shown in FIG. 8. The cylindrical portion 121 is a cylindrical portion on the inner peripheral side, and the outer end of the cylindrical portion 121. And a disk-shaped disk part 122 extending radially outward from the part. In the slinger 120, the cylindrical portion 121 is liquid-tightly fitted to the outer peripheral surface of the inner ring 202. An annular encoder 123 is attached to the outer surface of the disk part 122 over the entire circumference of the disk part 122.

  As shown in FIG. 8, in the sealing device 100, the side lip 115 of the sealing device body 110 abuts against the inner surface of the disk portion 122 of the slinger 120 with a predetermined tightening margin (contact width) to form a seal portion. doing. Further, the radial lip 116 of the sealing device body 110 abuts on the outer peripheral surface of the cylindrical portion 121 of the slinger 120 with a predetermined tightening margin to form a seal portion.

  Further, as shown in FIG. 8, an outer tapered surface 117, which is an annular surface extending obliquely in the outer and outer peripheral directions, is formed at the outer end of the cylindrical portion 113 of the elastic body portion 112 of the sealing device main body 110. ing. The encoder 123 covers the outer peripheral end of the disk portion 122 of the slinger 120, and the outer peripheral end 124 of the encoder 123 has an inner side extending in parallel to the outer tapered surface 117 of the cylindrical portion 113. A tapered surface 125 is formed. The outer tapered surface 117 and the inner tapered surface 125 are opposed to each other in the radial direction to form an annular gap 101. The annular narrow gap 101 forms a labyrinth seal (see, for example, Patent Document 1).

  As described above, in the conventional sealing device 100, in addition to the side lip 115 and the radial lip 116, first, foreign matters such as rain water and muddy water enter the inside of the sealing device 100 by the labyrinth seal formed by the gap 101. Is suppressed. Even if a minute foreign matter passes through the gap 101, the seal portion formed by the side lip 115 and the radial lip 116 prevents the foreign matter from entering the wheel bearing device 200.

  FIG. 9 is a partial cross-sectional view showing a schematic configuration of another sealing device attached to a conventional wheel bearing device. As shown in FIG. 9, the conventional sealing device 130 is similar to the conventional sealing device 100 described above, in the wheel bearing device 210, an annular space between the outer ring 211 and the inner ring 212 that rotate relative to each other coaxially. 213 is press-fitted. Similar to the wheel bearing device 200, the wheel bearing device 210 is a rolling bearing. The sealing device 130 suppresses foreign matter from entering the space 213.

  As shown in FIG. 9, the sealing device 130 includes an annular sealing device main body 140 that is fitted into the outer ring 211, and an annular slinger 150 that is fitted onto the inner ring 212. The sealing device main body 140 includes an annular reinforcing ring 141 and an elastic body portion 142 made of a rubber material integrally formed so as to cover the reinforcing ring 141. The reinforcing ring 141 has a substantially L-shaped cross section along the axis, as shown in FIG. 9, and the cylindrical portion on the outer peripheral side of the reinforcing ring 141 fits the inner peripheral surface of the outer ring 211 in a liquid-tight manner. Has been. The elastic body part 142 is formed on the inner peripheral side and the outer side of the reinforcing ring 141, and includes a cylindrical cylindrical part 143 on the outer peripheral side and a base part 144 formed on the inner peripheral side of the cylindrical part 143. The base portion 144 includes a side lip 145 that extends outward in the axial direction, and a radial lip 146 that extends in the radial direction and is divided into two branches. On the outer surface of the cylindrical portion 143, a concave annular recess 147 is formed on the inner side, and on the cylindrical portion 143, a protruding protrusion 148 is formed on the inner peripheral side.

  The slinger 150 is made of metal, and the cross-sectional shape along the axis is substantially L-shaped as shown in FIG. 9, and a cylindrical portion 151 that is a cylindrical portion on the inner peripheral side, and an outer side of the cylindrical portion 151. And a disk-shaped disk part 152 extending radially outward from the end part. In the slinger 150, the cylindrical portion 151 is liquid-tightly fitted to the outer peripheral surface of the inner ring 212. An annular encoder 153 is attached to the outer surface of the disk portion 152 over the entire circumference of the disk portion 152, as in the sealing device 100 described above.

  The encoder 153 covers the outer peripheral end of the disk portion 152 of the slinger 150, and the outer peripheral end 154 of the encoder 153 is formed with an annular protrusion 155 that is convex inward. The projecting body 155 enters the recess 147 of the cylindrical portion 143 of the elastic body part 142, and a narrow gap extending in the axial direction between the inner peripheral surface of the projecting body 155 and the outer peripheral surface of the projecting body 148. 131 is formed. Further, a narrow gap 132 extending in the radial direction is also formed between the distal end portion of the protrusion 148 and the inner surface of the disk portion 152. These gaps 131 and 132 form a labyrinth seal.

  Further, as shown in FIG. 9, in the sealing device 130, the side lip 145 has a predetermined tightening allowance on the inner surface of the disk portion 152 of the slinger 150, and the radial lip 146 has a predetermined allowance on the outer peripheral surface of the cylindrical portion 151 of the slinger 150. The seal part is formed by abutting and holding (see, for example, Patent Document 2).

  As described above, in the conventional sealing device 130, as in the conventional sealing device 100, first, foreign substances such as rainwater and muddy water enter the sealing device 130 by the two labyrinth seals formed by the gaps 131 and 132. Infiltration is suppressed. Even if a minute foreign matter passes through the gaps 131 and 132, the seal portion formed by the side lip 145 and the radial lip 146 prevents the foreign matter from entering the wheel bearing device 200.

JP 2007-285499 A JP 2010-185465 A

  In the conventional sealing devices 100 and 130, the labyrinth seal can improve the foreign matter blocking performance to prevent foreign matter from entering the inside. However, for example, intrusion of extremely small foreign matter or the like cannot be completely prevented even by a labyrinth seal. In addition, since the gaps 101, 131, and 132 forming the labyrinth seal are very narrow, when the foreign matter passes through the labyrinth seal and enters the inside thereof, the foreign matter is discharged out of the sealing devices 100 and 130. This is difficult, and foreign substances are accumulated inside the sealing devices 100 and 130. Further, the foreign matters accumulated in the sealing devices 100 and 130 damage the sliding portions of the side lips 115 and 145 and the radial lips 116 and 146, and the sealing performance of the sealing device is reduced. Performance will be degraded. In this case, the foreign matter enters the inside of the wheel bearing devices 200 and 210, and problems such as rust occur inside the wheel bearing devices 200 and 210. As described above, the conventional sealing device has a problem that it is difficult to discharge the foreign matter that has entered the interior through the labyrinth seal.

  In the sealing device 130, since the widths of the gaps 131 and 132 are narrow, even when the sealing device main body 140 or the slinger 150 is slightly decentered, the protruding body 155 of the encoder 153 and the protruding body 148 of the elastic body portion 142 are used. However, the ridge 148 and the disk portion 152 of the slinger 150 come into contact with each other. For this reason, the sliding resistance between the sealing device main body 140 and the slinger 150 increases, and the rotational torque of the sealing device 130 increases. For this reason, troubles such as frictional heat generation and torque loss occur in the sealing device 130. Thus, in the conventional sealing device, an increase in rotational torque due to contact at the labyrinth seal portion has been a problem.

  The present invention has been made in view of the above-described problems, and the object thereof is to improve the discharge performance of foreign matter such as rainwater and muddy water that has entered the inside, and to reduce the rotational torque. It is to provide a sealing device that can be used.

  In order to achieve the above object, a sealing device according to the present invention includes an annular outer peripheral member that is rotatable relative to each other about an axis, and an annular inner peripheral member that is at least partially surrounded by the outer peripheral member. A sealing device that seals between the outer peripheral side member and the inner peripheral side member in a mechanism comprising a sealing device main body attached to the outer peripheral side member, a slinger attached to the inner peripheral side member, and the slinger A flange member having elasticity attached to the sealing device body, and the sealing device body includes an annular reinforcing ring centered on the axis, and the axis formed from an elastic body attached to the reinforcing ring. The slinger is an annular metal member centered on the axis, and the elastic body portion is at least one in contact with the slinger. The flange member is an annular member centered on the axis, and has at least one annular projecting body centered on the axis at the outer peripheral end, the projecting body comprising: An annular gap centered on the axis is formed between the elastic body portion, and the axial thickness becomes thinner as the axis moves away from the axis, and the cross-sectional area of the gap is the gap The inner side of the gap is wide and the outer side of the gap is narrow.

  In the sealing device according to an aspect of the present invention, the protrusion protrudes most in a direction away from the axis in a portion on the side opposite to the object to be sealed in the axial direction.

  In the sealing device according to one aspect of the present invention, the elastic body portion includes at least one step portion corresponding to the at least one protrusion, and the step portion is centered on the axis of the elastic body portion. An annular step and an annular surface continuing to the step on the side opposite to the object to be sealed are formed, and spaced from the projecting body in a direction away from the axis. It is arrange | positioned facing the said protrusion.

  In the sealing device according to an aspect of the present invention, the surface formed by the stepped portion is a tapered surface that increases in diameter toward the side opposite to the object to be sealed.

  In the sealing device according to an aspect of the present invention, at least one of the protrusions and at least one of the stepped portions extend over the same range in the axial direction and face each other.

  In the sealing device according to an aspect of the present invention, at least one of the protrusions is shifted toward the object to be sealed in the axial direction and faces at least one of the stepped portions.

  The sealing device according to an aspect of the present invention includes a plurality of the protrusions, a plurality of the step portions, and the protrusions and the step portions are connected in the axial direction.

  In the sealing device according to the present invention, the protrusion of the annular flange member attached to the slinger forms a gap between the elastic body portion and a labyrinth seal is formed. The cross-sectional area is wide on the inner side and narrow on the outer side. For this reason, since a cross-sectional area is narrow from the outside, it is possible to make it difficult for foreign matter such as rainwater and muddy water to enter from the outside. Further, since the gap is wide from the inside through the gap, the foreign matter that has entered the inside can be easily discharged to the outside by the centrifugal force generated by the rotation of the sealing device. As described above, according to the sealing device of the present invention, it is possible to improve the discharge performance of foreign matters such as rainwater and muddy water that have entered the inside.

  In addition, the flange of the flange member has a thickness in the axial direction that becomes thinner in a direction away from the axis, and the protrusion has a tapered shape toward the outer peripheral side. For this reason, even when the sealing member main body and the slinger are eccentric and the ridge body contacts the elastic body portion, the contact surface pressure in the elastic body portion generated by the contact of the ridge body with the elastic body portion is reduced. The rotational torque of the sealing device can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows schematic structure of the sealing device which concerns on the 1st Embodiment of this invention, FIG.1 (a) is sectional drawing in the cross section along the axis line of a sealing device, FIG.1 (b) It is an expanded sectional view of the sealing device shown to Fig.1 (a). FIG. 2 is an enlarged view for enlarging and showing the vicinity of an outer peripheral end portion of a flange member in FIG. 1 and an outer end portion of a cylindrical portion of an elastic body portion. It is a fragmentary sectional view for showing the use condition of the sealing device which concerns on the 1st Embodiment of this invention shown in FIG. FIG. 2 is an enlarged view for enlarging and showing the vicinity of a gap of the sealing device in order to explain the function of the sealing device shown in FIG. 1. FIG. 4 is a view for showing a state in which an outer ring or an inner ring is eccentric in the wheel bearing device shown in FIG. 3. It is an expanded sectional view for showing the modification of the mode of the crevice in the sealing device concerning a 1st embodiment of the present invention. It is an expanded sectional view for showing a schematic structure of a sealing device concerning a 2nd embodiment of the present invention. It is a fragmentary sectional view for showing a schematic structure of the conventional sealing device attached to the bearing device for wheels. It is a fragmentary sectional view for showing schematic structure of the other conventional sealing device attached to the bearing device for wheels.

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

  FIG. 1 is a diagram illustrating a schematic configuration of a sealing device according to a first embodiment of the present invention, and FIG. 1A is a cross-sectional view taken along the axis of the sealing device, and FIG. b) is an enlarged sectional view of the sealing device shown in FIG.

  As shown in FIG. 1A, a sealing device 1 according to a first embodiment of the present invention includes an annular sealing device body 10 centered on an axis x and an annular slinger 20 centered on the axis x. With. The slinger 20 is disposed on the inner peripheral side of the sealing device body 10 so as to face the sealing device body 10. The sealing device 1 seals an annular space between two members that can rotate relative to each other about an axis x.

  The sealing device body 10 includes an elastic body portion 11 made of an annular elastic body centered on the axis x and an annular metal reinforcing ring 12 centered on the axis x. The elastic body portion 11 is integrally attached to the reinforcing ring 12. Examples of the elastic body of the elastic body portion 11 include various rubber materials, such as nitrile rubber (NBR), hydrogenated nitrile rubber (H-NBR), acrylic rubber (ACM), fluorine rubber (FKM), and the like. It is rubber. Examples of the metal material of the reinforcing ring 12 include stainless steel and SPCC (cold rolled steel).

  As shown in FIGS. 1 (a) and 1 (b), the elastic body portion 11 has a cylindrical cylindrical portion 13 centering on the axis x extending on the outer peripheral side, and an inner periphery from the inner end of the cylindrical portion 13. And a base portion 14 extending in the direction. Here, for convenience of explanation, the outer side is the direction of the arrow a (see FIG. 1A) in the axis x direction, and the inner side is the direction of the arrow b (see FIG. 1A) in the axis x direction. That is, the inner side is a direction (sealing target side) facing a region where the sealed object is present in use, and the outer side is a direction facing a region where foreign matter is present as described later. 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. 1A) is the outer peripheral side, and the direction approaches the axis x (FIG. 1). The direction of arrow d in FIG.

  The base portion 14 includes side lips 15 and 16 that extend outward and a radial lip 17 that extends radially inward. The side lips 15, 16 are provided on the outer peripheral side of the radial lip 17, and the side lip 15 is provided on the outer peripheral side of the side lip 16. As shown in FIG. 1A, the side lips 15 and 16 extend while being inclined with respect to the direction of the axis x. For example, the side lips 15 and 16 extend in a direction inclined from the direction of the axis x to the outer peripheral side. In the shape of a conical cylinder whose diameter increases toward the outside. As shown in FIG. 1 (a), the radial lip 17 extends while being inclined with respect to the axis x direction. For example, the radial lip 17 extends in a direction inclined toward the inner peripheral side from the axis x direction. It has a conical cylindrical shape that decreases in diameter toward the inside.

  The reinforcing ring 12 has a substantially L-shaped cross section (hereinafter also simply referred to as “cross section”) along the axis x, and a cylindrical outer peripheral portion 12a centering on the axis x and the outer peripheral portion 12a. And a disk-shaped disk part 12b centering on the axis x extending in the inner circumferential direction from the inner end part. An elastic body portion 11 is attached to the reinforcing ring 12 from the inner peripheral side and the outer side, and the elastic body portion 11 is reinforced. Specifically, the cylindrical portion 13 of the elastic body portion 11 is attached to the outer peripheral portion 12a of the reinforcing ring 12 from the inner peripheral side, and as shown in FIG. 1B, the outer end of the outer peripheral portion 12a. The part is covered with and embedded in the cylindrical part 13. Further, the base portion 14 of the elastic body portion 11 is attached to the disc portion 12b of the reinforcing ring 12 from the outside, and as shown in FIG. 1B, the end portion on the inner peripheral side of the disc portion 12b is Covered and embedded in the base portion 14.

  The reinforcing ring 12 is manufactured by, for example, pressing or forging, and the elastic body portion 11 is formed by cross-linking (vulcanization) molding using a molding die. At the time of this cross-linking molding, the reinforcing ring 12 is disposed in the mold, the elastic body portion 11 is bonded to the reinforcing ring 12 by vulcanization adhesion, and the elastic body portion 11 is molded integrally with the reinforcing ring 12. Is done.

  The slinger 20 is a member made of metal, for example, stainless steel, and is a plate-like annular member centered on the axis x. The slinger 20 has a cylindrical cylindrical portion 21 centered on the axis x on the inner peripheral side, and a disk-shaped disc portion 22 centered on the axis x extending from the outer end of the cylindrical portion 21 to the outer peripheral side. Is provided.

  As shown in FIG. 1B, the base portion 14 of the elastic body portion 11 of the sealing device body 10 is disposed so as to face the slinger 20. Specifically, the side lips 15 and 16 abut on the inner surface of the disk portion 22 of the slinger 20 with a predetermined tightening allowance (contact width) at the tip portion to form a seal portion. Further, the radial lip 17 abuts against the outer peripheral surface of the cylindrical portion 21 of the slinger 20 with a predetermined tightening margin at the distal end portion to form a seal portion.

  Further, the sealing device 1 includes a flange member 30. The flange member 30 is an annular member centered on the axis x, and is, for example, a disk-shaped member. Specifically, as shown in FIGS. 1A and 1B, the flange member 30 includes a disk portion 31 that is a disk-shaped portion and a disk portion that is an end portion on the outer peripheral side of the flange member 30. 31 and an outer peripheral end portion 32 connected to the outer peripheral end portion. The flange member 30 is attached to the slinger 20 so as to cover the disk portion 22 of the slinger 20 from the outside. Specifically, the disk portion 31 of the flange member 30 covers an outer surface 22 a that is an outer surface of the disk portion 22, and the outer peripheral end portion 32 of the flange member 30 is an outer peripheral end portion of the disk portion 22. The outer peripheral end 22b is covered. In the flange member 30, the disk part 31 and the outer peripheral end part 32 are integrally formed from the same elastic material.

  In the present embodiment, the disk portion 31 forms an encoder. Specifically, the disk portion 31 is formed of a permanent magnet such as a rubber magnet or a plastic magnet, and is magnetized so that N and S poles appear alternately at equal angular intervals in the circumferential direction. The disk part 31 as an encoder constitutes a rotational speed measuring device in cooperation with a magnetic sensor (not shown).

  And as shown in FIG.1 (b), the outer peripheral end part 32 of the flange member 30 has opposed the outer end part 13a which is a part of the outer end of the cylindrical part 13 of the elastic body part 11 in radial direction. A gap 2 is formed between the outer peripheral end portion 32 and the outer end portion 13a.

  FIG. 2 is an enlarged view for enlarging and showing the vicinity of the outer peripheral end portion 32 of the flange member 30 and the outer end portion 13 a of the cylindrical portion 13 of the elastic body portion 11.

  As shown in FIG. 2, in the flange member 30, the outer peripheral end portion 32 includes a plurality of annular protrusions on the outer periphery thereof. In the present embodiment, the outer peripheral end portion 32 has three ridges including a first ridge 33, a second ridge 34, and a third ridge 35. The first, second, and third protrusions 33, 34, and 35 are the third protrusion 35, the second protrusion 34, and the first protrusion in the direction of the axis x from the inside to the outside. They are arranged in the order of 33. The first protrusion 33, the second protrusion 34, and the third protrusion 35 define the outer peripheral end surface of the flange member 30.

  As shown in FIG. 2, the first protrusion 33 is an annular protrusion that is convex in the outer circumferential direction, and includes a hollow disk-shaped end surface 33 a that is a hollow disk-shaped surface centered on the axis x, and an axis It is defined by a conical cylindrical tapered surface 33b centering on x. The taper surface 33 b is a curved surface that is concave in the direction toward the axis line x that increases in diameter toward the outside in the direction of the axis line x, and is an inner lower end 33 c that is the innermost end of the lowermost portion of the first protrusion 33. To the tip 33d which is the tip of the first protrusion 33. Moreover, the hollow disk-shaped end surface 33a is a surface orthogonal to the axis line x. Thus, the 1st protrusion 33 protrudes most in the direction away from the axis x in the outer part in the axis line x direction (tip 33c), and is provided with the pointed part.

  The second protrusion 34 has the same shape as the first protrusion 33, and the height thereof is different from that of the first protrusion 33 and is lower than that of the first protrusion 33. ing. That is, as shown in FIG. 2, the second protrusion 34 includes a hollow disk-shaped end surface 34a similar to the hollow disk-shaped end surface 33a, and a tapered surface 34b similar to the tapered surface 33b. The tapered surface 34b is a curved surface that is concave in the direction toward the axis x that increases in diameter toward the outside in the axial direction, and is an inner lower end that is the innermost end of the lowermost portion of the second protrusion 34. 34 c extends from the tip 34 d which is the tip of the second protrusion 34. Moreover, the hollow disk-shaped end surface 34a is a surface orthogonal to the axis line x. As described above, the distance from the axis x of the tip 34d is shorter than the distance from the axis x of the tip 33d.

  The third protrusion 35 has the same shape as the first and second protrusions 33 and 34, and the height thereof is lower than that of the second protrusion 34. That is, as shown in FIG. 2, the third protrusion 35 is defined by a hollow disk-shaped end surface 35a similar to the hollow disk-shaped end surfaces 33a and 34a and a tapered surface 35b similar to the tapered surfaces 33b and 34b. Has been. The tapered surface 35b is a curved surface that is concave in the direction toward the axis x that increases in diameter toward the outside in the axial direction, and from the inner lower end 35c that is the innermost end of the lowermost portion of the third protrusion 35. , And extends over the tip 35d, which is the tip of the third protrusion 35. As described above, the distance from the axis x of the tip 35d is shorter than the distance from the axis x of the tip 34d.

  Thus, the 1st protrusion body 33, the 2nd protrusion body 34, and the 3rd protrusion body 35 have the thin tip part, and become a shape which is easy to elastically deform.

  As shown in FIG. 2, the hollow disc-shaped end surface 33 a of the first protrusion 33 forms a part of the outer surface of the flange member 30. A hollow disc-like end surface 34a of the second protrusion 34 extends from the inner lower end 33c of the first protrusion 33, and the third protrusion 34c extends from the inner lower end 34c of the second protrusion 34. 35 hollow disk-shaped end surfaces 35a extend. The inner lower end 35 c of the third protrusion 35 is connected to the inner end face of the outer peripheral end portion 32 of the flange member 30.

  As shown in FIG. 2, the outer end portion 13 a of the cylindrical portion 13 of the elastic body portion 11 includes a plurality of annular step portions on the inner periphery thereof. In the present embodiment, the outer end portion 13a has two step portions, ie, a first step portion 18 and a second step portion 19. The first and second stepped portions 18 and 19 are arranged in the order of the second stepped portion 19 and the first stepped portion 18 from the inner side to the outer side in the axis x direction. The first step portion 18 and the second step portion 19 define an inner peripheral end surface of the outer end portion 13 a of the tubular portion 13.

  As shown in FIG. 2, the first step portion 18 includes a step 18 a that forms one step recessed toward the outer peripheral side from the inner side toward the outer side in the axis x direction over the entire circumference of the outer end portion 13 a. A surface 18b that is an annular surface extending outward from the step 18a is formed. The surface 18b is a tapered surface that increases in diameter toward the outside in the direction of the axis x. In the first stepped portion 18, a step 18a starts from an inner end 18c that is an inner end, and a surface 18b ends at an outer end 18d that is an outer end.

  The second step portion 19 has the same shape as the first step portion 18 as shown in FIG. That is, the second step portion 19 includes a step 19a similar to the step 18a and a surface 19b similar to the surface 18b. The step 19a starts from the inner end 19c, which is the inner end, and forms a step that is recessed toward the outer periphery over the entire circumference of the outer end portion 13a. The surface 19b is a tapered surface that increases in diameter toward the outside in the direction of the axis x, and ends at an outer end 19d that is an outer end.

  As shown in FIG. 2, the outer end 18d of the first step portion 18 is connected to the outer end surface of the outer end portion 13a. The second step portion 19 is connected to the inner end 18c of the first step portion 18 at the outer end 19d. The second stepped portion 19 is connected to a tapered surface 13c formed on the inner peripheral surface 13b of the cylindrical portion 13 at the inner end 19c. The taper surface 13c is a surface that increases in diameter toward the outside in the direction of the axis x.

  The first protrusions 33 are opposed to the first step portion 18 with a gap in the radial direction. Specifically, the 1st protrusion 33 and the 1st level | step-difference part 18 have spread over the same range in the axis line x direction, and have mutually opposed. That is, the inner lower end 33c of the first protrusion 33 and the inner end 18c of the first step portion 18 are located on the same straight line orthogonal to the axis x. Further, the tip 33d of the first protrusion 33 and the outer end 18d of the first step 18 are located on the same straight line perpendicular to the axis x.

  Similarly to the relative position between the first protrusion 33 and the first step 18 described above, the second protrusion 34 is spaced apart from the second step 19 in the radial direction. Specifically, the second protrusion 34 and the second stepped portion 19 are spread over the same range in the axis x direction and face each other.

  Similarly to the relative position between the first protrusion 33 and the first stepped portion 18 described above, the third protrusion 35 is a tapered surface of the inner peripheral surface 13b of the cylindrical portion 13 in the radial direction. Specifically, the third protrusion 35 and the tapered surface 13c are spread over the same range in the direction of the axis x and face each other.

  Thus, the 1st protrusion body 33 and the 2nd protrusion body 34, the 1st level | step-difference part 18, and the 2nd level | step-difference part 19 mutually oppose, and incline to an outer peripheral side from the axis line x direction. The gap 2 is formed. In the gap 2, the first protrusion 33 and the first step 18 form a space 3 between the second protrusion 34 and the second step 19. A space 4 is formed between them.

  Further, each of the spaces 3 and 4 has a cross-sectional area by a cross section orthogonal to the axis x that is wide on the inner side and narrower on the outer side. Similarly, since the gap 2 is located on the inner side of the space 4, the cross-sectional area is wider on the inner side, and the outer side of the space 3 is located on the outer side, so that the outer side is narrower. .

  As described above, in the sealing device 1, a seal portion by a labyrinth seal is formed in the gap 2, and a seal portion is formed by abutting the side lips 15, 16 and the radial lip 17 on the slinger 20. ing. In the foreign material intrusion path, seal portions are formed in the order of the gap 2 (labyrinth seal), the side lip 15, the side lip 16, and the radial lip 17 from the upstream.

  Next, the usage state of the sealing device 1 according to the first embodiment of the present invention will be described. FIG. 3 is a partial cross-sectional view for illustrating a use state of the sealing device 1 according to the first embodiment of the present invention. In this Embodiment, the sealing device 1 shall be used for the wheel bearing apparatus which supports a wheel rotatably in vehicles, for example, a motor vehicle.

  As shown in FIG. 3, the sealing device 1 is attached to the wheel bearing device 40 so that foreign matter such as rainwater and muddy water does not enter the inside of the wheel bearing device 40 from the outside. In the wheel bearing device 40, an inner ring 42, which will be described later, can rotate, and the outer ring 41 cannot rotate.

  The wheel bearing device 40 is a conventionally known wheel bearing device, and is an outer ring 41 as an annular outer peripheral member and an inner ring 42 as an annular inner peripheral member, which are coaxially rotatable relative to each other about the axis x. With. The inner ring 42 is at least partially surrounded by the outer ring 41 with an annular space 43. Further, a plurality of rolling elements 44 are annularly arranged between the outer ring 41 and the inner ring 42, and the rolling elements 44 are held by a cage (not shown). The wheel bearing device 40 may have a plurality of rows of rolling elements 44 arranged in an annular shape. The space 43 is filled with grease for lubricating the rolling elements 44.

  The sealing device 1 is fitted between the outer ring 41 and the inner ring 42 at the outer end, and seals the space 43 from the outside. Here, the outside is a portion covered with the atmosphere, and the inside is a portion in the space 43 sealed by the sealing device 1. Similarly to FIG. 1, the inner side is the direction of the arrow a in the direction of the axis x, and the outer side is the direction of the arrow b in the axis x.

  Specifically, in the sealing device body 10, the cylindrical portion 13 of the elastic body portion 11 and the outer peripheral portion 12 a of the reinforcing ring 12 are fitted into the outer ring 41 and fixed to the outer ring 41. The outer peripheral surfaces of the cylindrical portion 13 and the outer peripheral portion 12 a are in liquid-tight contact with an inner peripheral surface 41 a that is an inner peripheral surface of the outer ring 41.

  Further, the slinger 20 is fixed to the inner ring 42 with the cylindrical portion 21 fitted on the inner ring 42. The inner peripheral surface of the cylindrical portion 21 is in liquid-tight contact with an outer peripheral surface 42 a that is an outer peripheral surface of the inner ring 42.

  Next, the function of the sealing device 1 will be described. FIG. 4 is an enlarged view for enlarging and showing the vicinity of the gap 2 of the sealing device 1 in order to explain the function of the sealing device 1.

  As shown in FIG. 4, a narrow gap 2 is formed in the sealing device 1, and a labyrinth seal is formed to prevent intrusion of foreign matters such as rainwater and muddy water into the inside. However, a very small foreign substance or the like may enter the gap 2. A solid arrow line I is a line indicating a foreign substance intrusion route.

  As shown in FIG. 4, in the sealing device 1, in the gap 2, a space 3 is formed by the first protruding body 33 and the first stepped portion 18, and the second protruding body 34 and the second stepped portion are formed. A space 4 is formed by the portion 19, and each of the spaces 3 and 4 has a large sectional area on the inner side and a smaller sectional area on the outer side. For this reason, each space 3 and 4 has a narrow gap from the outside, so that it is difficult for foreign matter such as rainwater and muddy water to enter from the outside. Can be easily discharged to the outside by the centrifugal force generated by the rotation of the sealing device 1.

  Moreover, in each space 3 and 4, as shown by the arrow line I, the foreign matter enters along the surfaces 18b and 19b of the step portions 18 and 19, and collides with the steps 18a and 19a. Then, the foreign matter proceeds in the inner circumferential direction and stays on the tapered surfaces 33b and 34b.

  When the inner ring 41 rotates and the slinger 20 and the flange member 30 rotate, the centrifugal force in the radial direction acts on the foreign matter staying on or accumulating on the tapered surfaces 33b and 34b, as indicated by the dotted arrow line O. In addition, the foreign matter moves in the direction of the surfaces 18b and 19b and is discharged to the outside along the surfaces 18b and 19b. Further, since the surfaces 18b and 19b are inclined surfaces extending in the outer peripheral direction as described above, the foreign matter biased in the direction of the surfaces 18b and 19b by the centrifugal force is caused by the surfaces 18b and 19b. Is urged outward along the line. For this reason, the staying foreign matter is easily discharged to the outside by centrifugal force.

  The gap 2 has two continuous spaces 3 and 4. For this reason, the invading foreign matter loses momentum of ingress in stages due to retention in the spaces 3 and 4. For this reason, it can be made more difficult for a foreign material to pass through the gap 2, and the blocking performance of the foreign material by the gap 2 can be further improved.

  In the wheel bearing device 40, when the outer ring 41 or the inner ring 42 is eccentric, the first protrusion 33 and the first step 18, and the second protrusion 34 and the second step are provided. The parts 19 come into contact with each other. FIG. 5 is a diagram for illustrating a state in which the outer ring 41 or the inner ring 42 is eccentric in the wheel bearing device 40. From this eccentricity, as shown in FIG. 5, the tip 33d of the first protrusion 33 is on the surface 18b of the first step 18 and the tip 34d of the second protrusion 34 is the second step 19. Each of the surfaces 19b is contacted. Further, the tip 35d of the third protrusion 35 is in contact with the tapered surface 13c. Here, the first, second, and third protrusions 33, 34, and 35 have thin tip portions and are easily elastically deformed. Therefore, even if the first and second protrusions 33 and 34 are in contact with the first and second step portions 18 and 19, and the third protrusion 35 is in contact with the tapered surface 13c, the first and second protrusions 33 and 34 are in contact with each other. The contact surface pressure applied to the step portions 18 and 19 and the tapered surface 13c is small. As a result, the first protrusion 33 and the first step portion 18, the second protrusion 34 and the second step portion 19, and the third protrusion 35 and the tapered surface 13 c are formed. Even when they contact each other, the frictional resistance generated on the contact surface can be reduced, and the rotational torque of the sealing device 1 can be reduced.

  As described above, according to the sealing device 1 according to the first embodiment of the present invention, it is possible to improve the discharge performance of foreign matters such as rainwater and muddy water that have entered the inside, and the sealing device at the time of eccentricity. 1 can be reduced. For this reason, durability of the wheel bearing device can be improved.

  Next, a modification of the aspect of the gap 2 in the sealing device 1 according to the first embodiment of the present invention will be described. FIG. 6 is an enlarged cross-sectional view for showing a modification of the mode of the gap 2 in the sealing device 1 according to the first embodiment of the present invention. In this modification, as shown in FIG. 6, between the first protrusion 33 and the first step 18, and between the second protrusion 34 and the second step 19. Further, the relative positional relationship between the third protrusion 35 and the tapered surface 13c is different from that of the sealing device 1 according to the first embodiment of the present invention.

  In the present modification, as shown in FIG. 6, the first protrusion 33 has a distal end 33 d in the line direction orthogonal to the axis line x and the step 18 a of the surface 18 b of the first step portion 18 and the outer end. It is arrange | positioned so as to oppose the position between 18d. Similarly, the second protrusion 34 has a tip 34d facing the position between the step 19a of the surface 19b of the second step 19 and the outer end 19d in the direction perpendicular to the axis x. It is arranged to do. Similarly, the third protrusion 35 has a tip 35d at the inner end and the outer end of the tapered surface 13c (the inner end 19c of the second step portion 19) in the direction perpendicular to the axis x. It arrange | positions so that the position between may be opposed. That is, as compared with the first embodiment, the first and second protrusions 33 and 34 and the third protrusion 35 are formed on the first and second step portions 18 and 19 and the tapered surface 13c. It is moved relatively inward.

  With this configuration, as shown in FIG. 6, in each stepped portion 18, 19, the steps 18 a, 19 a are opposed to the tapered surfaces 33 b, 34 b of the projecting bodies 33, 34 in the radial direction. For this reason, the foreign matter (arrow line I) that has entered the chambers 3 and 4 and collided with the steps 18a and 19a stays in a wide range of the tapered surfaces 33b and 34b. Accordingly, foreign substances can be easily retained in the chambers 3 and 4.

  Next, a sealing device 50 according to a second embodiment of the present invention will be described. FIG. 7 is an enlarged cross-sectional view for illustrating a schematic configuration of a sealing device 50 according to the second embodiment of the present invention. The sealing device 50 according to the second embodiment of the present invention differs from the sealing device 1 according to the first embodiment of the present invention only in the configuration of the flange member 30. Hereinafter, the same or similar components as those of the sealing device 1 according to the first embodiment of the present invention will be denoted by the same reference numerals, description thereof will be omitted, and only different parts will be described.

  As shown in FIG. 7, the sealing device 50 according to the second embodiment of the present invention includes a flange member 51 attached to the slinger 20, similarly to the sealing device 1. Unlike the flange member 30 of the sealing device 1, the flange member 51 does not include the disk portion 31 and is formed only from the outer peripheral end portion 32. That is, the sealing device 50 according to the present embodiment does not have an encoder function. Like the flange member 30, the flange member 51 includes a first protrusion 33, a second protrusion 34, and a third protrusion 35, and an outer peripheral end of the slinger 20 on the inner peripheral side. It is fixed to the part 22b. The flange member 51 is formed of an elastic material such as various rubber materials, for example, a synthetic rubber such as nitrile rubber (NBR), hydrogenated nitrile rubber (H-NBR), acrylic rubber (ACM), or fluorine rubber (FKM). Yes.

  Also in the sealing device 50 having the above-described configuration, the same effect as the sealing device 1 can be obtained.

  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, the shapes of the elastic body portion 11, the reinforcing ring 12, the slinger 20, and the like are not limited to the above-described shapes.

  Moreover, the shape of the 1st, 2nd, 3rd protrusion 33,34,35 is not restricted to the said shape. For example, the first, second, and third protrusions 33, 34, and 35 do not have a tapered surface, but are formed of a cylindrical surface and an annular protrusion that protrudes in the outer circumferential direction located outside the cylindrical surface. May be. Moreover, this protrusion may have a pointed end, and may be a circumferential surface with a flat tip.

  Moreover, the shape of the 1st, 2nd level | step-difference parts 18 and 19 is not restricted to the said shape. For example, the first and second stepped portions 18 and 19 may have cylindrical surfaces 18a and 19a extending in the axis x direction. Further, in place of the tapered surface 13c of the inner peripheral surface 13b of the cylindrical portion 13, a stepped portion similar to the first and second stepped portions 18 and 19 may be provided.

  Further, the flange members 30 and 51 may have only one protrusion body, and the elastic body portion 11 may have only one step portion, and the flange members 30 and 51 protrude. There may be three or more strips, and the elastic body portion 11 may have three or more step portions.

  Further, in the sealing device 1 according to the present embodiment, the disk portion 31 of the flange member 30 includes the encoder. However, the function applicable to the disk portion 31 is not limited to the encoder.

  In addition, the sealing devices 1 and 50 according to the present embodiment are applied to the wheel bearing device, but the application target of the sealing device according to the present invention is not limited to this, and the present invention exhibits. The present invention is applicable to all configurations that can utilize the effect.

1, 50, 100, 130 Sealing device 2, 101, 131, 132 Gap 10, 110, 140 Sealing device body 11, 112, 142 Elastic body portion 12, 111, 141 Reinforcement ring 12a Outer peripheral portion 12b Disk portion 13, 113, 143 Cylindrical portion 13a Outer end portion 13b Inner peripheral surface 13c Tapered surfaces 14, 114, 144 Base portions 15, 16, 115, 145 Side lips 17, 116, 146 Radial lip 18 First step portions 18a, 19a Step steps 18b, 19b Surface 18c, 19c Inner end 18d, 19d Outer end 19 Second stepped portion 20, 120, 150 Slinger 21, 121, 151 Cylindrical portion 22, 122, 152 Disc portion 22a Outer side surface 22b Outer end portion 30, 51 Flange member 31 Disc portion 32 Outer peripheral end portion 33 First protrusions 33a, 34a, 35a Hollow disc-like end 33b, 34b, 35b Tapered surfaces 33c, 34c, 35c Inner lower end 33d, 34d, 35d Tip 34 Second projecting body 35 Third projecting body 40, 200, 210 Wheel bearing device 41, 201, 211 Outer ring 41a Inner peripheral surface 42, 202, 212 Inner ring 42a Outer peripheral surface 43, 203, 213 Space 44 Rolling body 117 Outer tapered surface 123, 153 Encoder 124, 154 End 125 Inner tapered surface 147 Recessed portion 148, 155 Protruding body x axis

Claims (6)

Between the outer peripheral member and the inner peripheral member in a mechanism comprising an annular outer peripheral member rotatable relative to each other about the axis and an annular inner peripheral member at least partially surrounded by the outer peripheral member A sealing device for sealing,
A sealing device body attached to the outer peripheral member;
A slinger attached to the inner circumferential member;
A flange member having elasticity attached to the slinger,
The sealing device body includes an annular reinforcing ring centered on the axis, and an annular elastic body portion centered on the axis formed from an elastic body attached to the reinforcing ring,
The slinger is an annular metal member centered on the axis,
The elastic body portion includes at least one seal lip that contacts the slinger,
The flange member is an annular member centered on the axis, and includes at least one annular projecting body centering on the axis at an outer peripheral end, and the projecting body includes the elastic body portion. An annular gap centering on the axis is formed between the thickness of the gap and the thickness in the axial direction decreases as the distance from the axis increases. The gap has a wider cross-sectional area on the inner side of the gap. the external side of the gap has a narrow Kuna',
The elastic body portion includes at least one step portion corresponding to the at least one protrusion, and the step portion is an annular step in the axial direction centered on the axis line in the elastic body portion. And an annular surface that continues to the step on the side opposite to the object to be sealed, and is disposed opposite the ridge body with a space from the ridge body in a direction away from the axis. sealing device characterized in that is.   2. The sealing device according to claim 1, wherein the protruding body protrudes most in a direction away from the axis at a portion opposite to the object to be sealed in the axial direction. 3. The sealing device according to claim 1, wherein the surface formed by the stepped portion is a tapered surface having a diameter increasing toward a side opposite to a sealing object side. At least bracts of at least one said step portion of said projection member, any one of claims 1 to 3, characterized in that said are directly facing each other has spread over the same range in the axial direction The sealing device as described. At least one of the projection body is sealed object side deviation according to any one of claims 1 to 3, characterized in that opposite the at least one of said step portion in the axial direction Sealing device. The sealing according to any one of claims 1 to 5 , wherein a plurality of the protrusions are provided, a plurality of the step parts are provided, and the protrusions and the step parts are respectively connected in the axial direction. apparatus.

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