JP7398089B2 - sealing device - Google Patents

Description

The present invention relates to a sealing device that is installed between an outer member and an inner member that rotates coaxially with respect to the outer member, and is constructed by combining a first member and a second member.

Examples of the above-mentioned sealing device include one in which the slinger has a double cylindrical cross-sectional shape (inverted U-shape) to improve sealing performance, as disclosed in Patent Document 1 listed below. However, since muddy water and the like can enter even through a small gap, there is a need for something that has high sealing properties and can easily drain the muddy water and the like that have entered.
Therefore, in Patent Document 1 listed below, a double cylindrical (inverted U-shaped) slinger is used to improve sealing performance, and a plurality of discharge holes are provided in the annular plate portion of the slinger. Further, Patent Document 2 listed below discloses a sealing device in which a through hole having a tapered surface is provided in a circular ring portion of a slinger.

Japanese Patent Application Publication No. 2008-196585 JP2015-206441A

However, when a discharge hole or a through hole is provided in the vicinity of the seal lip that makes elastic contact with the slinger for sealing, as disclosed in the above cited documents 1 and 2, there is no leakage to the tip of the seal lip. There is a risk that muddy water or the like may get trapped, and in this case, it is difficult to extend the life of the sealing device.

The present invention has been made in view of the above-mentioned circumstances, and provides a novel sealing device that suppresses the infiltration of muddy water, etc. into the sealing device, improves the drainage of the muddy water, etc. that has entered, and maintains sealing performance for a long time. The purpose is to

The sealing device according to the present invention is a sealing device that is installed between an outer member and an inner member that rotates coaxially with respect to the outer member, and is configured by combining a first member and a second member, The first member includes an inner cylindrical portion that is fitted into the inner member, a disk portion extending radially outward from one end of the inner cylindrical portion, and an axially extending portion extending from one end of the disk portion to the outer diameter side. the second member has a cylindrical portion on the outer diameter side extending inward, and the second member includes a core metal that is fitted into the outer member, and a lip portion that is fixed to the core metal and comes into elastic contact with the disk portion of the first member. a seal lip portion made of an elastic body having a seal lip portion, and a drainage portion is provided in the outer diameter side cylindrical portion axially inward from a portion of the lip portion that is in elastic contact with the disk portion, The outer diameter side cylindrical part of the first member is arranged so that a labyrinth part is formed between the core metal cylindrical part of the core metal fitted into the outer member, and the outer diameter side cylindrical part A space is provided between and the lip part, and the drainage part is formed so as to communicate the labyrinth part and the space .
Further, another sealing device according to the present invention is a sealing device that is installed between an outer member and an inner member that rotates coaxially with respect to the outer member, and is configured by combining a first member and a second member. The first member includes an inner cylindrical portion fitted into the inner member, a disk portion extending from one end of the inner cylindrical portion to the outer diameter side, and one end of the disk portion. and a cylindrical portion on the outer diameter side extending inward in the axial direction, and the second member has a core metal fitted to the outer member and a disk portion of the first member that is fixed to the core metal. and a seal lip portion made of an elastic body having a lip portion that comes into elastic contact with the outer diameter side cylindrical portion, and a drainage portion is provided in the axial direction of the portion of the lip portion that makes elastic contact with the disk portion. The core metal of the second member includes a core metal cylindrical portion that is fitted into the inner circumferential surface of the outer member, and a core metal disc portion that extends from one end of the core metal cylinder portion toward the inner diameter side. The seal lip portion has a base portion that covers the outer surface of the one end portion, and a labyrinth portion is formed between the outer diameter side cylindrical portion of the first member and the base portion. A space is provided between the outer diameter side cylindrical part and the lip part, and the drainage part is formed so as to communicate the space with an external space. Features.
According to the above, since the drainage part is provided in the outer diameter side cylindrical part, even if muddy water or the like intrudes into the first member, it can be discharged from the drainage part. Further, even if muddy water or the like enters from the drainage part, it is prevented that the muddy water or the like falls directly onto the part of the lip part that is in elastic contact with the disk part, and it is possible to prevent the muddy water or the like from getting caught in the tip of the lip part. That is, according to the above, it is possible to improve both sealing performance and discharge performance, and it is possible to extend the life of the sealing device.

According to the sealing device according to the present invention, it is possible to suppress the intrusion of muddy water and the like into the sealing device, improve the discharge performance of the muddy water and the like that have entered, and maintain sealing performance for a long time.

1 is a schematic vertical sectional view schematically showing an example of a bearing device to which a sealing device according to the present invention is applied. (a) is an enlarged view of the X section in FIG. 1, and is a diagram schematically showing a first embodiment of a sealing device (inner seal) according to the present invention. (b) is a partial cross-sectional perspective view of the sealing device according to the same embodiment. 3 is a schematic perspective view schematically showing a first member of the sealing device shown in FIG. 2. FIG. (a) is a diagram schematically showing a modification of the sealing device according to the first embodiment, and corresponds to an enlarged view of the X section in FIG. 1. FIG. (b) is a partial cross-sectional perspective view of the sealing device according to the modification. 5 is a schematic perspective view schematically showing the first member of the sealing device shown in FIG. 4. FIG. (a) is an enlarged view of section Y in FIG. 1, and is a diagram schematically showing a second embodiment of the sealing device (outer seal) according to the present invention. (b) is a partial cross-sectional perspective view of the sealing device according to the same embodiment. (a) is a diagram schematically showing a modification of the sealing device according to the second embodiment, and corresponds to an enlarged view of section Y in FIG. 1. (b) is a partial cross-sectional perspective view of the sealing device according to the modification. (a) is a diagram schematically showing a further modified example of the sealing device according to the second embodiment, and corresponds to an enlarged view of the Y section in FIG. 1. (b) is a partial cross-sectional perspective view of the sealing device according to the modification. 9 is a schematic perspective view schematically showing the first member of the sealing device shown in FIG. 8. FIG.

Embodiments of the present invention will be described below based on the drawings. Note that some of the detailed symbols attached to other figures are omitted from some of the figures.
The sealing devices 10 and 11 according to the present embodiment are installed between an outer member 2 and an inner member 5 that rotates coaxially with respect to the outer member 2, and are constructed by combining a first member 50 and a second member 60. It is a sealing device. The first member 50 includes an inner cylindrical portion 501 that is fitted into the inner member 5, a disk portion 502 extending toward the outer diameter from one end 501a of the inner cylindrical portion 501, and one end 502a of the disk portion 502. The outer diameter side cylindrical portion 503 extends inward in the axial direction from the outer diameter side. The second member 60 has a seal lip portion made of an elastic material and has a core metal 61 that is fitted into the outer member 2 and a lip portion 621 that is fixed to the core metal 61 and comes into elastic contact with the disk portion 502 of the first member 50. 62. The outer cylindrical portion 503 is provided with a drainage portion 51 axially inside the portion of the lip portion 621 that comes into elastic contact with the disk portion 502 .
The details will be explained below.

<First embodiment>
First, a sealing device 10 according to a first embodiment will be described with reference to FIGS. 1 to 3.
FIG. 1 shows a bearing device 1 that rotatably supports wheels (not shown) of an automobile. This bearing device 1 generally includes an outer ring 2 as an outer member, a hub ring 3, an inner ring member 4 that is fitted and integrated with the vehicle body side of the hub ring 3, the outer ring 2, the hub ring 3, and the inner ring member. 4 and two rows of rolling elements (balls) 6 interposed between them. In this example, the hub ring 3 and the inner ring member 4 constitute an inner ring 5 as an inner member. The outer ring 2 is fixed to a vehicle body (not shown) of an automobile. Further, a drive shaft 7 is coaxially spline-fitted to the hub wheel 3, and the drive shaft 7 is connected to a drive source (drive transmission unit) (not shown) via a constant velocity joint 8. The drive shaft 7 is integrated with the hub wheel 3 by a nut 9, and the hub wheel 3 is prevented from coming off from the drive shaft 7. The inner ring 5 (hub ring 3 and inner ring member 4) is rotatable around an axis L with respect to the outer ring 2, and the outer ring 2 and the inner ring 5 constitute two members that rotate relatively. An annular bearing space S is formed between the members. In the bearing space S, two rows of rolling elements 6... are held in a retainer 6a, and the bearing rings 2a of the outer ring 2, the hub ring 3, and the bearing rings 3a, 4a of the inner ring member 4 can roll. It has been intervened. The hub wheel 3 includes a flange portion, and specifically includes a cylindrical hub body 30 that serves as the base of the flange portion, and a cylindrical hub body 30 that extends radially outward from the hub body 30 via an upright base 31. It has a hub flange 32 formed therein. Then, the wheel is attached and fixed to the hub flange 32 with bolts 33 and nuts (not shown). Hereinafter, the side facing the wheels along the axis L direction (the side facing left in FIG. 1) will be referred to as the wheel side, and the side facing the vehicle body (the side facing right in FIG. 1) will be referred to as the vehicle body side.

A sealing device 10 (inner seal) is provided at both ends of the bearing device 1 along the axis L direction, specifically, between the outer ring 2 and the inner ring member 4, and a sealing device is provided between the outer ring 2 and the hub ring 3. 11 (outer seal) is installed, and both ends of the bearing space S along the axis L direction are sealed. This prevents muddy water and the like from entering the bearing space S and preventing lubricant (grease, etc.) filled in the bearing space S from leaking to the outside.

The sealing device according to this embodiment is a sealing device 10 that is mounted on the vehicle body side, as shown in FIGS. 2(a) and 2(b). The sealing device 10 is configured by combining a double cylindrical first member 50 that is fitted onto the inner ring member 4 constituting the inner ring 5 and a second member 60 that is fitted inside the outer ring 2 .

The first member 50 is formed by pressing a steel plate such as SPCC, and has a double cylindrical shape with a U-shaped cross section. The first member 50 includes an inner cylindrical portion 501 that is fitted onto the outer diameter surface 4b of the inner ring member 4, and a circle that extends toward the outer diameter from one end 501a of the inner cylindrical portion 501 on the side opposite to the bearing space S. It includes a plate portion 502 and an outer diameter side cylindrical portion 503 extending from one end 502a of the disk portion 502 toward the second member 60 along the axis L direction. The lip portion 621 of the second member 60 comes into elastic contact with the surface 502b of the disc portion 502 on the bearing space S side. Furthermore, the radial lips 622 and 623 are in elastic contact with the outer diameter surface 501b of the inner diameter side cylindrical portion 501. In FIGS. 2(a) and 2(b), the two-dot chain line portions of the lip portion 621 and the radial lips 622, 623 indicate their original shapes before elastic deformation.

The second member 60 includes a core metal 61 that is fitted into the outer ring 2 and a rubber seal lip portion 62 that is fixed to the core metal 61. Specifically, the core metal 61 has a substantially L-shaped cross section, and includes a cylindrical core portion 611 that is fitted into the inner peripheral surface 2b of the outer ring 2 on the vehicle body side, and a bearing space of the cylindrical core portion 611. It includes an inward flange 612 extending radially inward from the S-side end 611a. The seal lip portion 62 is made of a rubber material, and includes a base portion 620 that is integrally fixed to the core bar 61 by vulcanization molding, one lip portion 621 extending from the base portion 620, and two radial lips 622, 623. Equipped with. The base 620 wraps around the inner peripheral edge 612b from a part of the surface 612a of the inward flange 612 on the bearing space S side of the core metal 61, and covers the entire surface of the surface 612c of the inward flange 612 on the side opposite to the bearing space S. It is fixedly integrated with the core metal 61 as shown in FIG. Further, the base portion 620 covers the entire inner diameter surface 611b of the cored metal cylindrical portion 611, and extends around the end portion 611c on the opposite side from the bearing space S to reach the outer diameter surface 611d of the cored metal cylindrical portion 611. It is fixed and integrated with gold 61. The portion of the base 620 that reaches the outer diameter surface 611d of the core metal cylindrical portion 611 is an annular protrusion 624 that protrudes toward the outer diameter side. , is formed so as to be interposed in a compressed state between the inner circumferential surface 2b of the outer ring 2 and the outer circumferential surface 611d of the cored metal cylindrical portion 611. The interposition of the annular protrusion 624 in a compressed state between the outer ring 2 and the cylindrical core 611 prevents muddy water or the like from entering the fitting portion between the outer ring 2 and the cylindrical core 611 . This prevents rust from forming in the fitting portion between the outer ring 2 and the cylindrical core metal portion 611, and also prevents muddy water and the like from entering into the bearing space S from the fitting portion. The two-dot chain line portion of the annular protrusion 624 shows its original shape before compression.

A drainage portion 51 is provided in the outer diameter side cylindrical portion 503 of the first member 50 on the inner side in the axis L direction (on the bearing space S side) of the elastic contact portion 621b of the lip portion 621 with respect to the disk portion 502. The drainage section 51 is provided to function to drain muddy water or the like that has entered the sealing device 10. As shown in FIGS. 2(b) and 3, the drainage portion 51 is provided in a notch shape at one location of the outer diameter side cylindrical portion 503, but is not limited to this, and is provided at intervals in the circumferential direction. You may provide more than one. The dimensions of the drainage section 51 are also not particularly limited, but if the drainage section 51 is too large, the drainage performance will improve, but the sealing performance will deteriorate. If the drainage portion 51 is too small, the sealing performance will be improved, but the drainage performance will be reduced. Therefore, for example, the dimension D1 of the drainage portion 51 may be 0.1 mm to 10 mm, and the dimension D2 may be 0.1 mm to 10 mm. In the example of FIG. 2(a), the dimension D1 is approximately twice the dimension D3.

The drainage section 51 is provided so that when the bearing device 1 rotates and the muddy water etc. is moved to a lower position where it is likely to be discharged, the drainage can be quickly drained from the opening. It may become an entry point for etc. Therefore, as described above, the drainage portion 51 is provided inside the elastic contact portion 621b of the lip portion 621 with respect to the disk portion 502 in the axis L direction (on the bearing space S side). The dimension D3 from the surface 502b of the disc portion 502 on the bearing space S side to the drainage portion 51 (see FIG. 2(a)) is not particularly limited, but is set to 0.5 mm or more. According to this, even if muddy water or the like enters from the drainage part 51, the muddy water or the like is prevented from falling directly onto the elastic contact part 621b of the lip part 621 with respect to the disc part 502, and the muddy water or the like is prevented from falling directly onto the elastic contact part 621b of the lip part 621. can prevent muddy water, etc. from getting stuck in the container.

The outer diameter side cylindrical portion 503 provided with the drainage portion 51 is arranged so that a first labyrinth portion R1 is formed between the outer diameter side cylindrical portion 503 and the core metal cylindrical portion 611 of the core metal 61 that is fitted into the outer ring 2 . The end portion 503a of the outer diameter side cylindrical portion 503 of the first member 50 is arranged so that a second labyrinth portion R2 is formed between the end portion 503a and the base portion 620 fixed to the inward flange portion 612 of the core metal 61. These first labyrinth portion R1 and second labyrinth portion R2 are gaps, and are assembled between the outer ring 2 and the inner ring member 4 so that the first member 50 and the second member 60 do not contact each other. A space 20 is provided between the outer diameter side cylindrical portion 503 and the lip portion 621, and the drainage portion 51 is formed so as to communicate the first labyrinth portion R1 and the space 20. The space portion 20 has a pocket shape surrounded by the outer diameter side cylindrical portion 503, the disk portion 502, the lip portion 621, and the base portion 620.

According to the above configuration, during operation of the bearing device 1, the first labyrinth portion R1 along the axis L direction and the second labyrinth portion R2 along the radial direction and the centrifugal action accompanying the axial rotation of the inner ring 5 interact. As a result, entry of muddy water containing dust into the sealing device 10 from the outside is suppressed. However, since the first labyrinth portion R1 and the second labyrinth portion R2 are gaps, it is not possible to completely prevent muddy water from entering, and some muddy water and the like will enter the sealing device 10. The muddy water and the like that have entered the sealing device 10 reach the space 20. Even if the muddy water and the like that have entered the space 20 are small, they gradually accumulate in the space 20. Since the inner ring 5 has a pocket shape, a pumping action is activated as the inner ring 5 rotates, and attempts to push the muddy water etc. that have entered into the drain part 51 back. When the drainage part 51 comes to a position where muddy water and the like can be easily discharged due to the rotation of the inner ring member 4, the muddy water and the like can be quickly discharged through the drainage part 51. Therefore, both sealing performance and discharge performance can be improved, and the life of the sealing device 10 can be extended.

<Modified example>
4 and 5 show a sealing device 10A as a modification of the same embodiment. This modified example is different from the example of the sealing device 10 shown in FIGS. 2 and 3 according to the first embodiment in that it includes a magnetic encoder 40, and that the drainage part 51 is not in the shape of a notch but in a cylindrical part on the outer diameter side. The difference is that a plurality of holes penetrating through 503 are provided. Furthermore, the configuration of the seal lip portion 62 is also different. Since the other configurations are the same as in the above example, common parts are given the same reference numerals and explanations of their functions and effects will be omitted.

A magnetic encoder 40 for rotation detection is fixedly and integrally provided on the vehicle body side surface 502c of the disc portion 502 of the sealing device 10A. The magnetic encoder 40 is integrally formed by vulcanization molding on the vehicle body side surface 502c of the disc portion 502 and the surface on the first labyrinth portion R1 side of the outer diameter side cylindrical portion 503, and is made of a rubber material containing magnetic powder, etc. N poles and S poles are magnetized alternately and at equal intervals in the circumferential direction. A magnetic sensor 12 is installed on the vehicle body (not shown) so as to face the magnetized surface 40a of the magnetic encoder 40, and the magnetic sensor 12 and the magnetic encoder 40 constitute a rotation detection mechanism for the inner ring 5 (wheel). Ru.

The seal lip portion 62 of the sealing device 10A includes two axial lips, specifically, a lip portion 621 extending from the base portion 620 and a disc lip portion 621 extending from the base portion 620 similarly to the lip portion 621. A side lip 625 is provided that slides into contact with the surface 502b of the portion 502 on the bearing space S side. It also differs from the sealing device 10 of FIG. 2 in that there is only one radial lip 623.

This modification differs from the sealing device 10 in that the drainage portion 51 is a penetrating hole. The drainage part 51 is formed by penetrating a part of the magnetic encoder 40 and the outer diameter side cylindrical part 503, and the drainage part 51 is located inside (in the axis L direction) of the elastic contact part 621b of the lip part 621 with respect to the disc part 502. (bearing space S side). The dimension D3 from the bearing space S side surface 502b of the disc portion 502 to the drainage portion 51 (see FIG. 4(a)) is not particularly limited, but is set to 0.5 mm or more. In the example of FIG. 4(a), the dimension D1 is approximately one third of the dimension D3.

A plurality of drainage portions 51 may be provided at intervals in the circumferential direction of the outer diameter side cylindrical portion 503. In this modification, approximately rectangular drainage portions 51 are provided at two locations 180° different from each other in the outer diameter side cylindrical portion 503. A shaped drainage section 51 is provided. The shape of the drainage portion 51 is not particularly limited to the illustrated example, and may be circular, elliptical, diamond-shaped, or the like. Further, the dimensions are not particularly limited, but for example, the dimension D1 may be 0.1 mm to 10 mm, and the dimension D2 may be 0.1 mm to 10 mm. If a plurality of drainage parts 51 are provided in this way, the drainage effect can be improved.

Also in this example, when the inner ring 5 is incorporated into the bearing device 1 shown in FIG. Infiltration of muddy water, etc. is suppressed, and even if muddy water, etc. enters, it can be quickly discharged by the drainage portion 51, which is the same effect as the above-described sealing device 10. Further, in the case of the sealing device 10A shown in this modification, as muddy water, etc. accumulates, dust contained in the muddy water, etc. is bitten by the elastic contact portion 621b of the lip portion 621 against the surface 502b of the disk portion 502 on the bearing space S side. The distal end portion 621a of the lip portion 621 may be worn due to the elastic sliding contact caused by the rotation of the inner ring 5. However, the sealing device 10A is provided with two axial lips, and the other side lip 625 located on the inner diameter side of the lip portion 621 comes into elastic contact with the surface 502b of the disc portion 502 on the bearing space S side. Even if the distal end portion 621a is worn out and muddy water or the like passes through the elastic contact portion of the lip portion 621 with the disk portion 502, the side lip 625 prevents further infiltration. Thereby, the sealing function of the sealing device 10A can be maintained for a long time.

<Second embodiment>
Next, referring to FIG. 6, a sealing device 11 according to a second embodiment will be described. The same reference numerals are given to parts common to those in the above example, and explanations of their functions and effects will be omitted.
The sealing device 11 shown in FIGS. 6(a) and 6(b) is a sealing device mounted on the wheel side. The sealing device 11 is configured by combining a double cylindrical first member 50 that is fitted onto the hub body 30 and a second member 60 that is fitted inside the outer ring 2 . The hub ring body 30 is a part of the hub ring 3 that constitutes the inner ring 5, and the hub ring body 30 constitutes the base of the flange portion.

The first member 50 includes an inner cylindrical portion 511 that is fitted onto the outer circumferential surface 30a of the hub ring body 30, and a circle that extends toward the outer diameter from an end 511a of the inner cylindrical portion 511 on the side opposite to the bearing space S. It includes a plate portion 512 and an outer diameter side cylindrical portion 513 extending from one end 512a of the disk portion 512 toward the second member 60 along the axis L direction. The lip portion 626 and side lip 627 of the second member 60 come into elastic contact with the surface 512b of the disc portion 512 on the bearing space S side. Furthermore, the radial lip 628 comes into elastic contact with the outer diameter surface 511b of the inner diameter side cylindrical portion 511. In FIGS. 6A and 6B, the two-dot chain line portions of the lip portion 626, side lip 627, and radial lip 628 show their original shapes before elastic deformation.

The core metal 61 of the second member 60 has a substantially L-shaped cross section, and includes a cylindrical core portion 601 that is fitted into the inner peripheral surface 2c of the outer ring 2 on the wheel side, and a hub flange of the cylindrical core portion 601. An inclined part 603 is bent and formed to be inclined inward from an end 601a on the hub flange 32 side, and an inward flange part 602 is formed to extend inward from an end 603a of the inclined part 603 on the hub flange 32 side. Be prepared. The seal lip portion 62 includes a base portion 620 that is integrally fixed to the core metal 61 by vulcanization molding, a lip portion 626 that is two axial lips extending from the base portion 620, a side lip 627, and one radial lip. 628. The base 620 extends around the inner circumferential edge 602b from a part of the surface 602a of the core metal 61 on the bearing space S side of the inward flange 602, and extends from the side of the inward flange 602 opposite to the bearing space S (i.e., the side of the hub flange 32). ) is integrally fixed to the core metal 61 so as to cover the entire surface 602c. Further, the base portion 620 is formed to cover the surface 603b of the inclined portion 603 on the hub flange 32 side, and the portion that covers the inclined portion 603 is formed thicker than the other portion. A portion covering this inclined portion 603 is provided with an annular protrusion 629 that protrudes toward the inner circumferential surface 2c of the outer ring 2 on the wheel side. This annular protrusion 629 is formed so as to be interposed in a compressed state between the inner circumferential surface 2c and the inclined portion 603 when the core metal 61 is fitted into the outer ring 2. By interposing the annular protrusion 629 in a compressed state between the outer ring 2 and the inclined portion 603, muddy water or the like is prevented from entering the fitting portion of the outer ring 2 and the cored metal cylindrical portion 601. This prevents rust from forming in the fitting portion between the outer ring 2 and the core metal cylindrical portion 601, and also prevents muddy water and the like from entering into the bearing space S from the fitting portion. The two-dot chain line portion of the annular protrusion 629 shows its original shape before compression.

A drainage portion 51 is provided in the outer diameter side cylindrical portion 513 of the first member 50 on the inner side in the axis L direction (on the bearing space S side) of the elastic contact portion 626b of the lip portion 626 with respect to the disk portion 512. The drainage portion 51 is provided in the shape of a notch at one location of the outer diameter side cylindrical portion 513, but is not limited to this, and as shown in FIGS. 4 and 5, a plurality of drainage portions are provided at intervals in the circumferential direction. It may be provided. The shape and dimensions of the drainage section 51 are not particularly limited, but for example, the dimension D1 may be 0.1 mm to 10 mm, and the opening dimension (not shown) of the drainage section 51 may be 0.1 mm to 10 mm. In the example of FIG. 6(a), the dimension D1 is approximately one third of the dimension D3.

As described above, the drainage portion 51 is provided inside the elastic contact portion 626b of the lip portion 626 with respect to the disc portion 512 in the axis L direction (on the bearing space S side). The dimension D3 from the bearing space S side surface 512b of the disc portion 512 to the drainage portion 51 (see FIG. 6(a)) is not particularly limited, but is set to 0.5 mm or more. According to this, even if muddy water or the like enters from the drainage part 51 as in the example of the first embodiment, the muddy water or the like is prevented from falling directly onto the elastic contact portion 626b of the lip part 626 with respect to the disc part 512, It is possible to prevent muddy water or the like from getting caught in the elastic contact portion 626b of the lip portion 626.

As shown in FIG. 6(a), the end portion 513a of the outer diameter side cylindrical portion 513 of the first member 50 is arranged so that a labyrinth portion R3 is formed between the end portion 513a and the base portion 620 fixed to the core bar 61. Ru. The labyrinth portion R3 is a gap, and is assembled between the outer ring 2 and the hub ring 3 so that the first member 50 and the second member 60 do not come into contact with each other. Specifically, the end portion 513a is assembled at the position of the end surface 2e of the outer ring 2 on the hub flange 32 side, and the base portion 620 is assembled so as not to protrude from the position of the end surface 2e. A space 20 is provided between the outer diameter side cylindrical portion 513 and the lip portion 626, and the drainage portion 51 is formed so as to communicate the space 20 with the external space. The space portion 20 has a pocket shape surrounded by the outer diameter side cylindrical portion 513, the disk portion 512, the lip portion 626, and the base portion 620.

According to the above configuration, while the bearing device 1 is in operation, the labyrinth portion R3 and the centrifugal action accompanying the shaft rotation of the inner ring 5 work together to prevent muddy water containing dust from flowing into the sealing device 11 from the external space. Infiltration is suppressed. However, since the labyrinth portion R3 is a gap, it is not possible to completely prevent muddy water from entering, and some muddy water and the like will enter the sealing device 11. The muddy water and the like that have entered the sealing device 11 reach the space 20, and even if it is a small amount, the muddy water and the like that have entered the space 20 are gradually accumulated in the space 20. However, since this space 20 has a pocket shape, a pumping action is activated as the inner ring 5 rotates, and attempts to push the muddy water etc. that have entered into the space 20 back toward the drainage portion 51 side. When the drainage part 51 comes to a position where muddy water and the like can be easily discharged due to the rotation of the inner ring 5, the muddy water and the like can be quickly discharged through the drainage part 51.
In addition, the sealing device 11 is configured such that as muddy water or the like accumulates, dust contained in the muddy water or the like gets caught in a portion 626b of the lip portion 626 that is in elastic contact with the surface 512b of the disc portion 512 on the bearing space S side. The tip portion 626a of the lip portion 626 may wear out due to the elastic sliding contact caused by rotation. However, similar to the modified sealing device 10A shown in FIG. Because of the elastic contact, even if the distal end portion 626a of the lip portion 626 is worn out and muddy water or the like passes through the portion of the lip portion 626 that is in elastic contact with the disc portion 512, the side lip 627 prevents further infiltration. Therefore, both sealing performance and discharge performance can be improved, and the life of the sealing device 11 can be extended.

<Modification 1>
FIG. 7 shows a sealing device 11A as a modification of the same embodiment. Modified example 1 described here differs from the example of the sealing device 11 shown in FIG. 6 according to the second embodiment in that the first member 50 is further radially outward than the outer circumferential surface 2d of the outer ring 2 on the wheel side. The difference is that the labyrinth portion R4 is arranged so that a labyrinth portion R4 is formed between it and 2d. The shape of the second member 60 is also different. Since the other configurations are the same as in the above example, common parts are given the same reference numerals and explanations of their functions and effects will be omitted.

The first member 50 of the sealing device 11A includes an inner cylindrical portion 511, a disk portion 512, and an outer cylindrical portion 513, and the outer cylindrical portion 513 has an outer diameter further than the outer circumferential surface 2d of the outer ring 2. It is formed to be located on the side. Therefore, since the disk portion 512 is naturally formed to extend further to the outer diameter side than the outer circumferential surface 2d of the outer ring 2, the disk portion 512 has a larger area than the disk portion 512 shown in FIG. 6(a). Further, an end portion 513a of the outer diameter side cylindrical portion 513 is formed to extend to a position covering the end surface 2e of the outer ring 2 on the hub flange 32 side. The lip portion 626 and the side lip 627 of the second member 60 are in elastic contact with the surface 512b of the disc portion 512 on the bearing space S side, and the radial lip 628 is in elastic contact with the outer diameter surface 511b of the inner diameter side cylindrical portion 511.

The core metal 61 of the second member 60 includes a core metal cylindrical portion 601 that is fitted into the inner circumferential surface 2c of the outer ring 2 on the wheel side, and an end portion 601b of the core metal cylindrical portion 601 on the bearing space S side toward the inner diameter side. An extending and bent inclined part 603, an inward flange part 602 formed to extend inward from an end 603a of the inclined part 603 on the hub flange 32 side, and an end of the cored metal cylindrical part 601 on the hub flange 32 side. An outward flange portion 604 is provided that extends from the portion 601a toward the outer diameter side. The outward flange 604 is fitted along the end surface 2e of the outer ring 2. The seal lip portion 62 includes a base portion 620 that is integrally fixed to the core metal 61 by vulcanization molding, a lip portion 626 that is two axial lips extending from the base portion 620, a side lip 627, and one radial lip. 628. The base 620 wraps around the inner peripheral edge 602b from a part of the surface 602a of the inward flange 602 on the bearing space S side of the core bar 61, and covers the entire surface of the surface 602c of the inward flange 602 on the side opposite to the bearing space S. , is provided so as to be interposed between the inclined portion 603 and the core metal cylindrical portion 601, and is fixed and integrated with the core metal 61 so as to cover the entire surface 604b of the outward flange portion 604 on the hub flange 32 side. . Further, the base 620 wraps around the surface 604a of the outward flange 604 on the end surface 2e side of the outer ring 2, and that portion is provided with an annular protrusion 629 that protrudes toward the end surface 2e. This annular protrusion 629 is formed so as to be interposed in a compressed state between the outward flange 604 and the end surface 2e when the core metal 61 is fitted into the outer ring 2. The annular protrusion 629 prevents muddy water, etc. from entering the fitting portion between the outer ring 2 and the core bar 61, thereby preventing rust, and also prevents muddy water, etc. from entering into the bearing space S from this fitting portion. is prevented.

Also in this modification, the drainage portion 51 is provided inside the elastic contact portion 626b of the lip portion 626 with respect to the disc portion 512 in the axis L direction (on the bearing space S side), and the drainage portion 51 is provided in the outer diameter side cylindrical portion. It is provided in one place of 513 in the shape of a notch. In the example shown in FIG. 7A, the dimension D1 is approximately half the dimension D3, and the opening is provided so as not to be located closer to the hub flange 32 than the end surface 2e. This makes it possible to prevent muddy water or the like that has entered from the drainage section 51 from attacking the tip 626a of the lip section 626.
Note that, as described above, a plurality of drainage portions 51 may be provided at intervals in the circumferential direction.

As shown in FIG. 7A, the outer diameter side cylindrical portion 513 of the first member 50 is arranged so that a labyrinth portion R4 is formed between the outer peripheral surface 2d of the outer ring 2 and the end portion 620a of the base portion 620. be done. The labyrinth portion R4 is a gap and is assembled between the outer ring 2 and the hub ring 3 so that the first member 50 and the second member 60 other than the seal lip portion 62 do not come into contact with each other. Specifically, the end portion 513a is assembled so as not to contact the outer peripheral surface 2d of the outer ring 2, and the base portion 620 is assembled so as not to protrude from the outer peripheral surface 2d. A space 20 is provided between the outer diameter side cylindrical portion 513 and the lip portion 626, and the drainage portion 51 is formed so as to communicate the space 20 with the external space. The space portion 20 has a pocket shape surrounded by the outer diameter side cylindrical portion 513, the disk portion 512, the lip portion 626, and the base portion 620.

Even with the above configuration, during operation of the bearing device 1, the labyrinth portion R4 and the centrifugal action accompanying the shaft rotation of the inner ring 5 work together to prevent muddy water containing dust from entering the sealing device 11A from the external space. is suppressed. When the drainage part 51 comes to a position where muddy water etc. can be easily discharged due to the rotation of the inner ring 5, the muddy water etc. can be quickly discharged through the drainage part 51.The effect is similar to that of FIG. 6(a), but In particular, the sealing device 11A shown in the modified example can have a longer distance from the labyrinth portion R4 and the space portion 20 to the lip portion 626 than the sealing device 11 shown in FIG. can be expected to have the effect of suppressing infiltration.

<Modification 2>
8 and 9 show a sealing device 11B as a modification of the same embodiment. Modified example 2 described here has the same configuration of the second member 60 as the example of the sealing device 11 shown in FIG. 6 according to the second embodiment, but differs in the configuration of the first member 50. Particularly different in that the first member 50 is arranged further on the outer diameter side than the wheel-side outer circumferential surface 2d of the outer ring 2 and so that labyrinth parts R5 and R6 are formed between the stepped outer circumferential surface 2d. . Since the other configurations are the same as in the above example, common parts are given the same reference numerals and explanations of their functions and effects will be omitted.

The first member 50 of the sealing device 11B includes an inner diameter side cylindrical part 511, a disk part 512, and an outer diameter side cylindrical part 513, and the outer diameter side cylindrical part 513 has an outer diameter further than the outer circumferential surface 2d of the outer ring 2. It is formed to be located on the side. The outer diameter side cylindrical portion 513 is formed to extend from the fitting portion 32a of the disc portion 512 of the hub flange 32 toward the wall portion 2f forming a stepped shape formed on the outer ring 2. Therefore, the outer diameter side cylindrical portion 513 naturally has a larger area than the outer diameter side cylindrical portion 513 shown in FIGS. 6(a) and 7(a). Further, the outer diameter side cylindrical portion 513 is disposed so as to cover the outer circumferential surface 2d of the outer ring 2, and its end portion 513a is disposed to face the wall portion 2f, and there is a gap between the end portion 513a and the wall portion 2f. becomes the labyrinth portion R5.

Also in this modification, the drainage portion 51 is provided inside the elastic contact portion 626b of the lip portion 626 with respect to the disk portion 512 in the axis L direction (on the bearing space S side). As shown in FIGS. 8 and 9, the drainage portion 51 is a hole penetrating the outer diameter side cylindrical portion 513, and is provided in a circular shape. The size of the drainage portion 51 (dimension D1) is approximately one-third the size of the outer diameter side cylindrical portion 513, and is provided so that the opening portion is not located closer to the hub flange 32 than the position of the end surface 2e. ing. As shown in FIG. 9, a plurality of drainage portions 51 are provided at intervals in the circumferential direction.

As shown in FIG. 8(a), in addition to the labyrinth portion R5, the outer diameter side cylindrical portion 513 of the first member 50 has a labyrinth portion R6 that is long in the axis L direction between it and the outer peripheral surface 2d of the outer ring 2. The first member 50 and the second member 60 other than the seal lip portion 62 are assembled between the outer ring 2 and the hub ring 3 so that they do not come into contact with each other. A space 20 is provided between the outer diameter side cylindrical portion 513 and the lip portion 626, and the drainage portion 51 is formed so as to communicate the space 20 with the external space. The space portion 20 has a pocket shape surrounded by the outer diameter side cylindrical portion 513, the disk portion 512, the lip portion 626, and the base portion 620.

With the above configuration, while the bearing device 1 is in operation, the labyrinth portions R5 and R6 and the centrifugal action accompanying the shaft rotation of the inner ring 5 combine to cause muddy water containing dust to flow from the external space into the sealing device 11B. Infiltration is suppressed. When the drainage part 51 comes to a position where muddy water etc. can be easily discharged due to the rotation of the inner ring 5, the muddy water etc. can be quickly discharged through the drainage part 51.The effect is similar to that shown in FIG. 6(a) etc. In particular, the sealing device 11B shown in the modified example has a sealing structure that covers not only the labyrinth portion R5 but also the distance from the labyrinth portion R6 to the lip portion 626 via the space portion 20 as shown in FIGS. 6(a) and 7(a). It can be longer than the devices 11 and 11A, and can be expected to be more effective in suppressing the infiltration of muddy water and the like.

The configurations of the sealing devices 10, 10A, 11, 11A, and 11B according to the above embodiments are not limited to the illustrated examples. Further, the configuration, shape, number, etc. of the first member 50, second member 60, magnetic encoder 40, seal lip portion 62, etc. are not limited to those in each of the above embodiments. For example, the second member 60 shown in FIG. 8(a) may be replaced with the second member 60 shown in FIG. 7(a). Furthermore, in the above embodiment, an example was described in which the sealing device according to the present invention is applied to a bearing device for an automobile, but the present invention is not limited to this. A sealing device installed between two members can be preferably applied to bearing devices in other industrial fields. Moreover, even if it is a bearing device for an automobile, it is not limited to the bearing device shown in FIG. 1, but may be a bearing device of other forms. Further, the shapes of the core bar 61 and the seal lip portion 62 fixed thereto are not limited to those shown in the drawings, and the shape of the fit between the core bar 61 and the outer ring 2 and the fit between the first member 50 and the inner ring 5 are The form etc. are not limited to the illustrated example. Further, the shape of the lip portion 626 and the like can be changed as appropriate depending on the required specifications. The labyrinth structure is not limited to the illustrated example. For example, in the inner seal shown in FIG. 2, etc., the outer diameter side cylindrical portion 503 is is arranged further radially outward from the outer circumferential surface of the outer ring 2 so that a labyrinth portion is formed between the outer circumferential surface, and the drainage portion 51 is formed to communicate the labyrinth portion with the external space. You can also use it as

2 Outer ring (outer member)
5 Inner ring (inner member)
10,10A Sealing device (inner seal)
11, 11A, 11B Sealing device (outer seal)
50 First member 501, 511 Inner diameter side cylindrical part 502, 512 Disk part 503, 513 Outer diameter side cylindrical part 40 Annular encoder 503a, 513a End part 60 Second member 61 Core metal 62 Seal lip part R1 First labyrinth part R2 2nd labyrinth part R3 to R6 Labyrinth part L axis

Claims (5)

A sealing device installed between an outer member and an inner member that rotates coaxially with respect to the outer member, and configured by combining a first member and a second member,
The first member includes an inner cylindrical portion that is fitted into the inner member, a disk portion extending radially outward from one end of the inner cylindrical portion, and an axially extending portion extending from one end of the disk portion to the outer diameter side. It has an outer diameter side cylindrical part extending inward,
The second member includes a core metal fitted to the outer member, and a seal lip portion made of an elastic body and having a lip portion that is fixed to the core metal and comes into elastic contact with the disk portion of the first member. death,
A drainage portion is provided in the outer diameter side cylindrical portion at an axially inner side of a portion of the lip portion that is in elastic contact with the disk portion,
The outer diameter side cylindrical portion of the first member is arranged so that a labyrinth portion is formed between the core metal cylindrical portion of the core metal fitted inside the outer member,
A space is provided between the outer diameter side cylindrical part and the lip part,
The sealing device is characterized in that the drainage section is formed to communicate the labyrinth section and the space section . A sealing device installed between an outer member and an inner member that rotates coaxially with respect to the outer member, and configured by combining a first member and a second member,
The first member includes an inner cylindrical portion that is fitted into the inner member, a disk portion extending radially outward from one end of the inner cylindrical portion, and an axially extending portion extending from one end of the disk portion to the outer diameter side. It has an outer diameter side cylindrical part extending inward,
The second member includes a core metal fitted to the outer member, and a seal lip portion made of an elastic body and having a lip portion that is fixed to the core metal and comes into elastic contact with the disk portion of the first member. death,
A drainage portion is provided in the outer diameter side cylindrical portion at an axially inner side of a portion of the lip portion that is in elastic contact with the disk portion,
The core metal of the second member has a core metal cylindrical part that fits into the inner peripheral surface of the outer member, and a core metal disc part that extends from one end of the core metal cylinder part toward the inner diameter side. , the seal lip portion has a base portion that covers the outer surface of the one end portion,
The outer diameter side cylindrical part of the first member is arranged so that a labyrinth part is formed between it and the base part,
A space is provided between the outer diameter side cylindrical part and the lip part,
The sealing device is characterized in that the drainage section is formed so as to communicate the space section with an external space . In claim 1 or claim 2,
The inner member has a flange portion,
A sealing device characterized in that the inner cylindrical portion is fitted into a base portion of the flange portion . In any one of claims 1 to 3,
A sealing device characterized in that a plurality of the drainage portions are provided at intervals in the circumferential direction . In any one of claims 1 to 4,
The sealing device is characterized in that the drainage portion has a hole or notch shape passing through the outer diameter side cylindrical portion .

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