sealing device

Abstract

The present invention provides a sealing device in which the ring-shaped protrusions of the sealing device exhibit excellent performance both in the stacked state before mounting to the bearing device and after mounting to the bearing device. [Solution] The core member 20A comprises a core cylindrical portion 21, a core ring portion 22, and a seal portion 25 made of a non-magnetic elastic material. The slinger member 30A comprises a slinger cylindrical portion 31, a slinger ring portion 32, and a magnetic encoder 35 fixed to the outer surface of the slinger ring portion 32. The seal portion 25 is provided with a ring projection 27 that protrudes inclined toward the rolling element 7 so as to form a gap 41 between it and the rolling element 7.

Description

Technical Field

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[0001] The present invention relates to a sealing device with a magnetic encoder that seals an annular space having rolling elements formed between a fixed member and a rotating member in a bearing device.

Background Art

[0002] As a conventional sealing device of this type, in order to prevent products from being difficult to separate due to magnetic adhesion on the upper and lower surfaces during storage before attachment to a bearing device and stacking during shipment, non-magnetic rubber is arranged on the lower surface (inner side in the bearing device) of the core member (core metal) of the upper sealing device facing the magnetic encoder of the lower sealing device. Various such proposals have been made.

[0003] For example, in the case of Patent Document 1, an annular ridge is provided by protruding rubber on the lower surface of the core material so that the upper and lower sealing devices do not adhere too closely over a large area.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, such an annular ridge does not exhibit any particular function after the sealing device is attached to the bearing device and becomes useless when the sealing device is attached to and used in the bearing device. <​​​​

[0007] To achieve the above objective, the present invention provides a sealing device for sealing an annular space having rolling elements inside, formed between a fixed member and a rotating member in a bearing device, comprising a core member that fits into the fixed member and a slinger member that fits into the rotating member, wherein the core member comprises a core cylindrical portion that fits into the fixed member, a core ring portion extending radially from the axial inner end of the core cylindrical portion, and a seal portion made of a non-magnetic elastic material fixed to the core ring portion, wherein the slinger member comprises a slinger cylindrical portion that fits into the rotating member, a slinger ring portion extending radially from the axial outer end of the slinger cylindrical portion, and a magnetic encoder fixed to the outer surface of the slinger ring portion, and wherein the seal portion is provided with a ring projection that is inclined toward the rolling elements so as to form a gap between it and the rolling elements. [Effects of the Invention]

[0008] Because the sealing device of the present invention has the configuration described above, the ring-shaped protrusions not only prevent mutual magnetization when products are stacked together, but also provide effective functionality even after being mounted on the bearing device. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic longitudinal cross-sectional view of a bearing device including a sealing device according to an embodiment of the present invention. [Figure 2] (a) is an enlarged view of section X in Figure 1, which is a schematic cross-section end view showing a sealing device according to the first embodiment, and (b) is a schematic cross-section end view showing a state in which multiple sealing devices are stacked. [Figure 3] (a) is an enlarged view of section X in Figure 1, which is a schematic cross-section end view showing a sealing device according to the second embodiment, and (b) is a schematic cross-section end view showing a state in which multiple sealing devices are stacked. [Modes for carrying out the invention]

[0010] The sealing device 10 according to the present invention will be described below with reference to the accompanying drawings. First, the general basic configuration common to the sealing device 10 according to the following multiple embodiments will be described.

[0011] The sealing device 10 is a device for sealing an annular space 6 having rolling elements 7 inside, which is formed between the fixed member 2 and the rotating member 3 in the bearing device 1, and comprises a core member 20A that fits into the fixed member 2 and a slinger member 30A that fits into the rotating member 3.

[0012] The core member 20A comprises a core cylindrical portion 21 that fits into the fixing member 2, a core ring portion 22 that extends radially from the axial inner end of the core cylindrical portion 21, and a seal portion 25 made of a non-magnetic elastic material fixed to the core ring portion 22.

[0013] The slinger member 30A comprises a slinger cylindrical portion 31 that fits onto the rotating member 3, a slinger ring portion 32 that extends radially from the axial outer end of the slinger cylindrical portion 31, and a magnetic encoder 35 fixed to the outer surface of the slinger ring portion 32.

[0014] The sealing portion 25 is equipped with a circular ring projection 27 that protrudes inclined toward the rolling element 7 so as to form a gap 41 between it and the rolling element 7.

[0015] Next, the basic configuration of the bearing device 1 to which the sealing devices 10 and 11 are attached will be described based on Figure 1. In this specification, as shown in Figure 1, the side facing the wheel (not shown) along the rotation axis L direction (hereinafter abbreviated as the axial direction) (the side facing left in Figure 1) is called the wheel side, and the side facing the vehicle body (not shown) (the side facing right in Figure 1) is called the vehicle body side.

[0016] In the bearing device 1 of FIG. 1, an outer ring member 2 is fixed to a vehicle body (not shown), two rows of rolling elements 7 are arranged on the inner side in the radial direction thereof, and further, a hub ring 3b and an inner ring 3a are supported rotatably about the axis inside thereof. The hub ring 3b has a hub flange 3c, and a driving wheel (not shown) is attached to the hub flange 3c by bolts 3d and nuts (not shown).

[0017] Further, a drive shaft 4 is coaxially spline-fitted to the hub ring 3b, and the drive shaft 4 is connected to a drive source (not shown) via a constant velocity joint 5. The drive shaft 4 is integrated with the hub ring 3b by a nut 4a, and the removal of the drive shaft 4 from the hub ring 3b is prevented.

[0018] The inner ring member 3 is constituted by the hub ring 3b and the inner ring 3a. This inner ring member 3 is capable of relative rotation about the rotation axis L with respect to the outer ring member 2. Between this inner ring member 3 and the outer ring member 2, the rolling elements 7 are interposed in a state of being held by a retainer 7a.

[0019] Thus, two members that rotate relatively are constituted by the outer ring member 2 and the inner ring member 3, and an annular space 6, which is a space portion including the interposed portion of the rolling elements 7, is formed between these two members. This annular space 6 is a bearing space and is a sealed space. In the present embodiment, the inner ring member 3 is a rotating member and the outer ring member 2 is a fixed member.

[0020] A sealing device 10 is attached to the end on the vehicle body side in the axial direction of the annular space 6. Also, another sealing device 11 is attached to the end on the wheel side of the annular space 6. By attaching the sealing devices 10 and 11 to both ends respectively in this way, both ends along the axial direction of the annular space 6 are sealed.

[0021] The annular space 6 is filled with a lubricant such as grease (not shown), whereby the rolling of the rolling elements 7 is made smooth. The sealing devices 10 and 11 have the function of preventing external leakage of this lubricant and preventing the intrusion of muddy water and dust from the outside into the annular space 6, and the function of discharging the intruded muddy water and the like.

[0022] Further, an annular magnetic encoder 35 (ring magnet) (see FIG. 2) is arranged on the vehicle body side surface of the slinger member 30A of the sealing device 10 mounted on the vehicle body side, and a magnetic sensor 15 is installed on the vehicle body at a position facing the magnetic encoder 35.

[0023] The magnetic encoder 35 is an elastic member formed integrally with the slinger main body 30 of the slinger member 30A to be described later, obtained by kneading magnetic powder into a rubber material, and having a large number of N poles and S poles alternately magnetized along its circumferential direction. The magnetic sensor 15 detects a magnetic change accompanying the rotation of the magnetic encoder 35. That is, the magnetic sensor 15 and the magnetic encoder 35 constitute a rotation detection mechanism of the wheel (inner wheel member 3), and an anti-lock braking system is constituted.

[0024] Next, the details of the sealing device 10 according to the first embodiment will be described with reference to FIGS. 2(a) and 2(b).

[0025] The slinger member 30A includes a slinger main body 30 made of metal and the above-described magnetic encoder 35.

[0026] The slinger body 30 comprises a slinger cylindrical portion 31 that fits onto the inner ring member 3, a slinger ring portion 32 extending radially outward from the axially outer end of the slinger cylindrical portion 31 (the outer side of the bearing device 1, the vehicle body side in Figure 1; the same applies hereinafter), and another slinger cylindrical portion 33 extending axially inward from the radially outer end of the slinger ring portion 32 (the inner side of the bearing device 1, the wheel side in Figure 1; the same applies hereinafter). Hereafter, the fitting slinger cylindrical portion 31 will be referred to as the first cylindrical portion 31, and the other slinger cylindrical portion 33 will be referred to as the second cylindrical portion 33. The slinger body 30 may be made of a hard synthetic resin material.

[0027] The magnetic encoder 35 is fixed to the slinger ring portion 32 and the second cylindrical portion 33 so as to cover substantially the entire outer surface of both the slinger ring portion 32 and the second cylindrical portion 33. The magnetic sensor 15 is positioned to face the portion of the magnetic encoder 35 corresponding to the slinger ring portion 32 (see Figure 1).

[0028] The core member 20A is formed by fixing and integrating a sealing portion 25 made of an elastic material such as rubber to a core body 20 made of metal. The core body 20 includes a core cylindrical portion 21 that fits into the outer ring member 2, and a core ring portion 22 that extends radially inward from the axial inner end of the core cylindrical portion 21. The core body 20 may be made of a hard synthetic resin material. The sealing portion 25 may be made of an elastic, soft synthetic resin material.

[0029] The cylindrical core portion 21 is formed thinner than the rest by cutting out the radial outer diameter side of its axial outer end 21a (open end). The ring portion 22 of the core has a step 22b formed in the middle of its radial direction so that its radial inner end 22a side approaches the axial outer side.

[0030] The seal portion 25 comprises a seal body portion 25a fixed to the entire surface of the inner corner between the core cylindrical portion 21 and the core ring portion 22, a first lip piece 25b that constitutes an axial lip, and a second lip piece 25c that constitutes a radial lip.

[0031] The seal body portion 25a is fixed to the core ring portion 22 at its radial inner end 22a, wrapping around to the axial inner surface of the core ring portion 22 and including a step 22b, and is also fixed to the core cylindrical portion 21 at its axial outer end 21a, wrapping around to the radial outer surface. The portion of the seal body portion 25a that wraps around to the axial inner surface of the core ring portion 22 is called the inner surface portion 25aa of the seal body.

[0032] The first lip piece 25b protrudes inclined toward the slinger ring portion 32 from the core ring portion 22 side so that its diameter increases and it is directed outward in the axial direction, while the second lip piece 25c protrudes inclined toward the first cylindrical portion 31 from the core ring portion 22 side so that its diameter decreases and it is directed inward in the axial direction.

[0033] Both the first lip piece 25b and the second lip piece 25c have the function of suppressing the inflow of muddy water from outside the sealing device 10 into the annular space 6, and suppressing the discharge of grease from the annular space 6 to outside the bearing device 1.

[0034] As shown in Figure 2(a), when the sealing device 10 is mounted in the annular space 6 of the bearing device 1, the first lip piece 25b elastically contacts the axial inner surface of the slinger ring portion 32, while the second lip piece 25c elastically contacts the outer diameter surface of the first cylindrical portion 31. The diagram of the first lip piece 25b shown by the dashed line is a diagram of the state before elastic deformation.

[0035] As the rotating member 3 rotates in the bearing device 1, the slinger member 30A and the core member 20A are in a relative rotational relationship, and the first lip piece 25b and the second lip piece 25c slide against their respective surfaces. However, at least one of the first lip piece 25b and the second lip piece 25c may not be in contact with the surface.

[0036] The seal portion 25 is further provided with a ring-shaped projection 27 that protrudes axially inward from a protruding base 27a midway along the radial direction of the inner surface portion 25aa of the seal body. A continuous, textured surface 27c (indicated by the thick line in Figure 2(a)) is formed on the end face of the tip portion 27b of the ring-shaped projection 27 and on the inner diameter surface near the tip portion 27b, which will be described later along with the explanation of Figure 2(b).

[0037] This ring-shaped projection 27 protrudes inclined toward the rolling element 7 from the inner surface portion 25aa of the seal body, with a diameter that is larger and directed inward in the axial direction. In short, the ring-shaped projection 27 has a hollow frustoconical shape with the end on the open side (rolling element 7 side) widening radially.

[0038] When the sealing device 10 is mounted on the bearing device 1, the ring-shaped projection 27 is close to the rolling element 7, and a gap 41 is formed between the ring-shaped projection 27 and the rolling element 7. This gap 41 is set so that the distance between the tip 27b of the ring-shaped projection 27 and the surface of the rolling element 7 is a minute distance, in order to prevent the grease (lubricant) distributed around the rolling element 7 from flowing out to the sealing device 10. In this way, the ring-shaped projection 27 acts as a labyrinth seal.

[0039] The distance between the tip 27b of the ring projection 27 and the surface of the rolling element 7 is preferably 0.1 mm or more and 0.5 mm or less, but of course, it is not limited to this value.

[0040] As shown in Figure 2(a), the annular ridge 27 divides the internal space 6a between the sealing device 10 and the rolling element 7 within the annular space 6 into space A and space B. In other words, excess grease and grease that tries to separate from the rolling element 7 are partially collected in space A by the annular ridge 27, thereby suppressing the outflow of grease to the sealing device 10 side and even to the outside of the bearing device 1. In short, space A can serve as a grease relief space.

[0041] The ring-shaped protrusion 27 acts as a labyrinth seal in this way, but even in the stacked state of multiple sealing devices 10 as shown in Figure 2(b), for example during storage or transport before being installed in the bearing device 1, the following effects are achieved.

[0042] In Figure 2(b), the sealing device 10, with the core member 20A and the slinger member 30A assembled, is stacked with the core member 20A positioned at the bottom. The lower sealing device 10 in the figure is placed on the installation surface S.

[0043] When the sealing devices 10 are stacked in this manner, the upper sealing device 10 and the lower sealing device 10 are in contact, with the ring-shaped projection 27 of the upper sealing device 10 and the magnetic encoder 35 of the lower sealing device 10 being in contact. However, parts other than the ring-shaped projection 27 and the magnetic encoder 35 are not in contact with each other.

[0044] The ring-shaped projection 27 has a tapered shape with its diameter widening downwards, forming an overall flattened hollow frustum. In particular, the projection base 27a and tip 27b are inclined to such an extent that their radial positions do not overlap.

[0045] Therefore, when the sealing devices 10 are stacked, the ring-shaped protrusions 27 made of elastic material are subjected to gravity and elastic deformation, causing the outer diameter surface portion 27d to be concave and compressed in the vertical direction, resulting in an overall flatter shape. In this way, the end face of the tip portion 27b of the ring-shaped protrusions 27 and the inner diameter surface nearby thereto come into contact with the surface of the mating magnetic encoder 35.

[0046] In this way, the ring-shaped projection 27 of the upper sealing device 10 comes into contact with the magnetic encoder 35 of the lower sealing device. On the other hand, other parts do not come into contact with each other. Moreover, since the ring-shaped projection 27 is made of a non-magnetic elastic material, the upper and lower sealing devices 10 do not become magnetically attached even when in contact with the magnetic encoder 35, and therefore each sealing device 10 can be easily handled.

[0047] Furthermore, due to the elastic deformation of the ring-shaped projection 27 as described above, a wider area consisting of the tip portion 27b and its nearby inner diameter surface comes into contact with the surface of the magnetic encoder 35. This allows the lower sealing device 10 to be pressed over a wider area, suppressing separation and lateral displacement between them. In particular, since the rubber materials are in contact with each other, lateral displacement is unlikely to occur.

[0048] Furthermore, because the ring-shaped projection 27 has a wider portion, including its tip 27b and the inner diameter surface nearby, that contacts the surface of the magnetic encoder 35, there is a risk of blocking due to excessive contact between the sealing devices 10. However, as shown in Figure 2(b), continuous irregularities 27c (shown by thick lines and cross-hatching) are formed on the tip 27b and the inner diameter surface nearby, which can suppress a strong contact relationship with the magnetic encoder 35.

[0049] In short, the contact between the rubber materials makes it less likely for the sealing devices 10 to shift laterally, while the continuous irregularities 27c on the contact surface make it easy to separate the sealing devices 10 in the vertical direction.

[0050] The continuous grooves 27c may be provided on the surface of the magnetic encoder 35 of the mating sealing device 10, either in place of or in addition to the ring-shaped protrusions 27.

[0051] Furthermore, the ring-shaped projection 27 changes to a flatter state due to the indentation of the outer diameter surface portion 27d caused by elastic deformation based on its frustoconical shape, and the radial outward movement of the tip portion 27b. This suppresses the need for the sealing device 10 to become significantly bulkier in the stacking direction when stacked.

[0052] In order for the ring-shaped projection 27 to function effectively when the sealing devices 10 are stacked as described above, it goes without saying that the ring-shaped projection 27 must be formed such that the radial position of the tip portion 27b of the ring-shaped projection 27 falls within the range of the magnetic encoder 35.

[0053] Specifically, assuming that the magnetic encoder 35 is positioned on both outer surfaces of the corners between the slinger ring portion 32 and the second cylindrical portion 33, it is desirable that the radial position of the tip portion 27b of the ring projection 27 be on the inner side of the radial position of the inner surface of the second cylindrical portion 33 (see, for example, the dashed line in Figure 2(a)). In particular, it goes without saying that it is necessary to consider that the ring projection 27 (outer surface portion 27d) will elastically deform and the diameter at the tip portion 27b will increase.

[0054] Next, the details of the sealing device 10 according to the second embodiment will be described with reference to Figures 3(a) and 3(b).

[0055] Compared to the sealing device in Figure 2, the slinger member 30A of this sealing device has the same configuration and shape, and the core body 20 of the core member 20A has the same configuration and shape. Furthermore, the sealing portion 25, specifically the sealing body 25a, the first lip piece 25b, and the second lip piece 25c, has the same configuration and shape as those in Figure 2. Therefore, a detailed explanation of these components will be omitted.

[0056] The circular ring projection 27 of the sealing device 10 differs in shape from the circular ring projection 27 of the sealing device 10 in Figure 2. The circular ring projection 27 in Figure 3 protrudes inclined toward the rolling element 7 from a protruding base 27a midway along the radial direction of the inner surface portion 25aa of the seal body, with a smaller diameter and directed inward in the axial direction. In short, the circular ring projection 27 has a shape that narrows radially at the end on the open side (rolling element 7 side).

[0057] Similar to that in Figure 2, the ring-shaped projection 27 is close to the rolling element 7 when the sealing device 10 is mounted on the bearing device 1, and a gap 41 is formed between the ring-shaped projection 27 and the rolling element 7. This gap 41 is set so that the distance between the tip of the ring-shaped projection 27 and the surface of the rolling element 7 is a minute, in order to prevent the grease (lubricant) distributed around the rolling element 7 from flowing out to the sealing device 10. In this way, the ring-shaped projection 27 acts as a labyrinth seal.

[0058] The distance between the tip 27b of the ring projection 27 and the surface of the rolling element 7 is preferably 0.1 mm or more and 0.5 mm or less, but of course, it is not limited to this value.

[0059] As shown in Figure 3(a), the annular ridge 27 divides the internal space 6a between the sealing device 10 and the rolling element 7 within the annular space 6 into space C and space D. In other words, excess grease and grease that tends to move away from the rolling element 7 are mostly collected in space C by the annular ridge 27, thereby suppressing the outflow of grease to the sealing device 10 side and even to the outside of the bearing device 1. In short, space C can serve as a grease relief space.

[0060] Furthermore, since space C is larger than space A formed by the ring-shaped protrusion 27 of the sealing device 10 in Figure 2, it is possible to store more grease, further suppressing grease leakage.

[0061] Furthermore, as shown in Figure 3(a), the ring-shaped projection 27 is close to and approximately parallel to the second lip piece 25c, and therefore acts as a double grease lip together with the second lip piece 25c. By creating a double lip in this way, the second lip piece 25c can be made non-contact with the slinger body 30, thereby reducing torque.

[0062] The ring-shaped protrusions 27 act as labyrinth seals in this manner, but even in the stacked state shown in Figure 3(b) before mounting to the bearing device 1, although the inclination direction is different, the same function and effect as in Figure 2 can be expected. The explanation of the stacked state will be omitted.

[0063] The ring-shaped projection 27 has a tapered shape with its diameter narrowing downwards, forming an overall flattened hollow frustum. In particular, the projection base 27a and tip 27b are inclined to such an extent that their radial positions do not overlap.

[0064] Therefore, when the sealing devices 10 are stacked, the ring-shaped protrusions 27 made of elastic material are subjected to gravity and elastic deformation, causing the outer diameter surface portion 27d to bulge outward and compress in the vertical direction, resulting in an overall flatter shape. In this way, the end face of the tip portion 27b of the ring-shaped protrusions 27 and the nearby outer diameter surface come into contact with the surface of the mating magnetic encoder 35.

[0065] Thus, the ring-shaped projection 27 of the upper sealing device 10 comes into contact with the magnetic encoder 35 of the lower sealing device. However, other parts do not come into contact with each other. Moreover, since the ring-shaped projection 27 is made of a non-magnetic elastic material, the upper and lower sealing devices 10 do not become magnetically attached even when in contact with the magnetic encoder 35, and therefore each sealing device 10 can be easily handled.

[0066] Furthermore, due to the elastic deformation of the ring-shaped projection 27 as described above, a wider area consisting of the tip portion 27b and its surrounding outer diameter surface comes into contact with the surface of the magnetic encoder 35. This allows the lower sealing device 10 to be pressed over a wider area, suppressing separation and lateral displacement between them. In particular, since the rubber materials are in contact with each other, lateral displacement is unlikely to occur.

[0067] Furthermore, as with Figure 2, it is desirable to provide continuous irregularities 27c (shown by thick lines and cross-hatching) on ​​the tip portion 27b and its surrounding outer diameter surface in order to suppress blocking caused by the sealing devices 10 being too tightly attached to each other.

[0068] Furthermore, the ring-shaped projection 27 changes to a flatter state due to the bulging of the outer diameter surface portion 27d (concave on the inner diameter surface) due to elastic deformation based on the frustoconical shape, and the radial movement of the tip portion 27b toward the inner diameter, thereby suppressing the bulkiness when the sealing devices 10 are stacked.

[0069] Furthermore, the ring-shaped projection 27 of the sealing device 10 in Figure 3 has its protruding base 27a positioned radially inward compared to that in Figure 2, and has a frustoconical shape that narrows downward. Additionally, the area of ​​the region enclosed by the circle that contacts the lower sealing device 10 is smaller, so the one in Figure 2 offers better stability when stacked.

[0070] In the sealing device 10 of Figure 3, as in Figure 2, it goes without saying that in order for the ring-shaped projection 27 to function effectively when the sealing devices 10 are stacked as described above, the ring-shaped projection 27 must be formed such that the radial position of the tip portion 27b of the ring-shaped projection 27 falls within the range of the magnetic encoder 35.

[0071] Specifically, assuming that the magnetic encoder 35 is positioned on both outer surfaces of the corners between the slinger ring portion 32 and the second cylindrical portion 33, it is desirable that the radial position of the tip portion 27b of the ring projection 27 be on the outer diameter side of the radial position of the outer diameter surface of the first cylindrical portion 31 (see, for example, the dashed line in Figure 2(a)). In particular, it goes without saying that it is necessary to consider that the ring projection 27 (outer diameter surface portion 27d) will elastically deform and the diameter at the tip portion 27b will decrease.

[0072] In the embodiments described above, a sealing device 10 was illustrated in which the fixed member 2 is an outer ring member and the rotating member 3 is an inner ring member. However, the present invention can also be applied to a device in which the fixed member 2 is an inner ring member and the rotating member 3 is an outer ring member.

[0073] The sealing device 10 described above is merely an example, and other designs are also acceptable. Furthermore, it goes without saying that the overall shape of the sealing device 10 can be modified as appropriate from a design perspective. [Explanation of Symbols]

[0074] 1. Bearing device 2. Fixing member (outer ring member) 3. Rotating member (inner ring member) 3a Inner ring 6. Ring-shaped space (sealed space) 6a Interior space 7 Rolling element 10 Sealing device 11. Sealing devices (other sealing devices) 15 Magnetic Sensor 20A Core material 20 Core Body 21 Core cylindrical part 22 Core ring part 25 Seal part 25a Seal body 25aa Inner surface of the seal body 25b First lip piece 25c Second lip piece (grease lip) 27 Circular protrusion 27a Protruding base 27b Tip 27c Continuous uneven surface 27d Outer diameter surface 30A Slinger component 30 Slinger body 31. Slinger cylindrical section (first cylindrical section) 32 Slinger ring section 33 Other slinger cylindrical parts (second cylindrical part) 35 Magnetic Encoder 41 gap

Claims

1. A sealing device for sealing an annular space containing rolling elements, formed between a fixed member and a rotating member in a bearing device, The system comprises a core member that fits into the fixed member and a slinger member that fits into the rotating member, The core member comprises a core cylindrical portion that fits into the fixing member, a core ring portion extending radially from the axial inner end of the core cylindrical portion, and a seal portion made of a non-magnetic elastic material fixed to the core ring portion. The slinger member comprises a slinger cylindrical portion that fits onto the rotating member, a slinger ring portion extending radially from the axial outer end of the slinger cylindrical portion, and a magnetic encoder fixed to the outer surface of the slinger ring portion. The sealing device is characterized in that the sealing portion has a circular ring projection that is inclined toward the rolling element so as to form a gap between it and the rolling element.

2. In claim 1, The aforementioned ring ridge is characterized in that a continuous uneven surface is formed on the axial inner surface of the bearing device.

3. In claim 1, The magnetic encoder is a sealing device characterized in that continuous irregularities are formed on the axial outer surface of the bearing device.

4. In claim 1, The sealing device is characterized in that the ring-shaped projection has a shape in which the open end widens radially.

5. In claim 1, The aforementioned ring-shaped projection is characterized in that the end on the open side is tapered in the radial direction.

Images