Magnetic encoder and bearing device

Abstract

The present invention provides a magnetic encoder that allows for a larger detection surface dimension regardless of the size of the rotating member or the size of the mounting recess for the magnetic encoder. [Solution] The magnetic encoder 40 is formed on the axial end face 2d of the rotating member 2, and has a recessed groove 2e having groove walls 2ea and 2eb on both radial sides. The magnetic encoder 40 is attachable to the recessed groove 2e and is formed separately from the sealing member 18. It comprises a mounting portion 42 that is mounted in the recessed groove 2e, and a main body portion 41 connected to the mounting portion 42 and having a flange portion 41b that abuts against at least one end face 2d adjacent to the recessed groove 2e in the radial direction.

Description

Technical Field

[0001] The present invention relates to a magnetic encoder mounted on a bearing device to which a sealing device can be attached, and a bearing device provided with the magnetic encoder.

Background Art

[0002] Conventionally, various magnetic encoders that are directly mounted on the rotating member of a bearing device have been proposed. In particular, Patent Document 1 discloses a magnetic encoder fixed to a notch-shaped step portion formed at a corner of a rotating member so as to fill the space of the step portion.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problem to be Solved by the Invention

[0004] However, the magnetic encoder of Patent Document 1 has a small exposed portion facing the magnetic sensor, which may cause detection errors by the magnetic sensor. In addition, since the magnetic encoder is adhesively fixed to the notch-shaped step portion provided at the corner, it is difficult to replace.

[0005] The present invention has been proposed in consideration of such circumstances, and its object is to provide a magnetic encoder that allows the dimension of the detection surface to be increased regardless of the size of the rotating member or the size of the mounting recess of the magnetic encoder, and a bearing device provided with the magnetic encoder.

Means for Solving the Problem

[0006] To achieve the above objective, the magnetic encoder of the present invention is a magnetic encoder mounted on the rotating member in a bearing device comprising a fixed member and a rotating member that rotates coaxially with respect to the fixed member, and having a mounting space between the fixed member and the rotating member for mounting a sealing member, wherein a recessed groove having groove walls on both radial sides is formed on the axial end face of the rotating member, and the magnetic encoder is mounted on the rotating member having a mounting portion that is mountable in the recessed groove and is formed separately from the sealing member, and is mounted in the recessed groove, and a main body portion coupled to the mounting portion and having a flange portion that abuts against at least one end face adjacent to the recessed groove in the radial direction.

[0007] Furthermore, the bearing device of the present invention is characterized by comprising a fixed member, a rotating member, and a magnetic encoder as described in claim 1. [Effects of the Invention]

[0008] Because the present invention has the configuration described above, the dimensions of the sensing surface of the magnetic encoder can be increased regardless of the size of the rotating member or the size of the mounting recess for the magnetic encoder. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic cross-section end view showing an example of a vehicle bearing device equipped with a magnetic encoder according to an embodiment of the present invention. [Figure 2] (a) is a schematic enlarged view of part X1 in Figure 1, showing a cross-section end view of the seal member mounted on the bearing device and the magnetic encoder according to the first embodiment, and (b) and (c) are cross-section end views schematically showing two examples of mounting structures for magnetic encoders of other shapes according to the same embodiment. [Figure 3] (a) to (c) are schematic cross-sectional end views showing three examples of a magnetic encoder according to the second embodiment. [Figure 4] (a) to (d) are schematic cross-sectional end views showing four other examples of the magnetic encoder according to the second embodiment. [Figure 5](a) and (b) are schematic cross-sectional end views showing two other examples of the magnetic encoder according to the second embodiment. [Modes for carrying out the invention]

[0010] Embodiments of the present invention will be described below with reference to the accompanying drawings. First, we will describe the common basic configuration of the multiple magnetic encoders 40A and 40B according to the embodiment.

[0011] These magnetic encoders 40A and 40B are components mounted on the rotating member 2 of a bearing device 1, which comprises a fixed member 3 and a rotating member 2 that rotates coaxially with respect to the fixed member 3, and has a mounting space between the fixed member 3 and the rotating member 2 for which a sealing member 18 is attached.

[0012] A groove 2e is formed on the axial end face 2d of the rotating member 2, having groove walls 2ea and 2eb on both radial sides. The magnetic encoder 40 is attachable to the groove 2e and is formed separately from the sealing member 18. The encoder 40 comprises a mounting portion 42 that is mounted in the groove 2e, and a main body portion 41 connected to the mounting portion 42 and having a flange portion 41b that abuts against at least one end face 2d adjacent to the groove 2e in the radial direction.

[0013] Both of these magnetic encoders 40A and 40B are equipped with a flange portion 41b, which allows the detection surface of the magnetic sensor 15 to be arranged in a wide manner regardless of the width dimension (radial dimension) of the groove 2e. Therefore, the detection performance of the magnetic sensor 15 mounted opposite the magnetic encoders 40A and 40B can be improved, and detection errors can be suppressed.

[0014] Next, three examples of the magnetic encoder 40A according to the first embodiment will be described with reference to Figures 1 and 2. First, the bearing device 1 on which the magnetic encoder 40A is mounted will be described. In this bearing device 1, the outer ring member 2 rotates relative to the fixed inner ring member 3, thereby achieving coaxial rotation.

[0015] The bearing device 1 shown in Figure 1 includes an axle tube 4 through which a drive shaft 5 is inserted along the direction of the rotation axis L, and a bearing (outer ring 2b and inner ring 3a) that is fitted onto an outer peripheral step portion 4b formed on the outer periphery 4a of the axle tube 4 and rotatably supports a wheel.

[0016] Note that on the paper surfaces of Figure 1 and Figure 2, the left side is defined as the wheel side and the right side as the vehicle body side, and in the following description, one axial side is referred to as the wheel side and the other axial side as the vehicle body side. In addition, the portion indicated by the two-dot chain line in the drawing of Figure 2 is the original shape before deformation.

[0017] Figure 1 shows, as an example of the bearing device 1 to which the seal member 18 of the sealing device 11 is mounted, a bearing device that drives a wheel by a full-floating type drive shaft 5 used in heavy vehicles such as trucks and buses.

[0018] This bearing device 1 has an axle tube 4 through which the drive shaft 5 is inserted, a hub wheel 2a, an outer ring 2b, a pair of inner rings 3a, a plurality of tapered rollers 9 arranged as rolling elements, and a cage 9a that retains the tapered rollers 9. The hub wheel 2a and the outer ring 2b constitute an outer ring member 2, and the pair of inner rings 3a constitute an inner ring member 3.

[0019] The hub wheel 2a is connected to the flange 6 of the drive shaft 5 by bolts 7, and power from a differential gear (not shown) is transmitted to the hub wheel 2a. Further, the outer ring 2b is fitted inside the hub wheel 2a, and the hub wheel 2a is rotatably supported by the outer ring 2b. The outer ring 2b is fitted inside the hub wheel 2a, is formed at the wheel-side end of the outer periphery 4a of the axle tube 4, and is fitted onto the outer peripheral step portion 4b.

[0020] Specifically, the outer ring 2b is fitted into the inner peripheral surface of the hub wheel 2a, inserted until the vehicle-body-side end surface 3c of the inner ring 3a abuts against the wall surface 4c of the outer peripheral step portion 4b, and in this state, is tightened and fixed to the wheel-side end surface 3d of the inner ring 3a by an annular fixing member 8.

[0021] The outer ring 2b, the pair of inner rings 3a, and the plurality of tapered rollers 9 are made of a metal material, and the plurality of tapered rollers 9 are rollably interposed between the raceway ring 2c of the outer ring 2b and the raceway ring 3b of the inner ring 3a while being held by the cage 9a.

[0022] The annular space between the outer ring member 2 and the inner ring member 3 where the tapered rollers 9 are arranged is a sealed space 10, which is defined as a space sealed by the seal member 18.

[0023] In the bearing device 1 shown in Figure 1, an annular seal member 18 is mounted at the end on the vehicle body side in the rotation axis L direction of the sealed space 10 (see part X1 in Figure 1), and another annular seal member 18A is mounted at the end on the wheel side of the sealed space 10.

[0024] The sealed space 10 is filled with a lubricant (not shown) such as grease, which allows the tapered rollers 9 to roll smoothly. The seal member 18 and the other seal member 18A have the functions of preventing the lubricant from leaking to the outside, preventing muddy water and dust from entering the sealed space 10 from the outside, and discharging the muddy water and the like that have entered.

[0025] As shown in Figure 1 and Figure 2, the seal member 18 according to the present embodiment (see part X1 in Figure 1) is mounted between the outer ring 2b and the inner ring 3a, which constitute the bearing and are opposed to each other in the radial direction, in the bearing device 1.

[0026] The seal member 18 corresponding to part X1 in Figure 1 will be described with reference to Figures 2(a) to 2(c). The seal member 18 is the main constituent material of the sealing device 11, and is configured to include two members.

[0027] The seal member 18 shown in Figure 2 includes a seal lip member 20 formed by fixing an elastic material such as a rubber material (elastic member 22) to a core bar 21 made of a metal material or a hard synthetic resin material, and a slinger 30 made of a metal material or a hard synthetic resin material.

[0028] The core metal 21 comprises a core metal disc portion 21a extending radially and a core metal cylindrical portion 21b extending toward the vehicle body from the outer diameter end of the core metal disc portion 21a. When the seal lip member 20 is mounted on the bearing device 1, the core metal cylindrical portion 21b is positioned to fit (internally fit) with respect to the outer ring member 2.

[0029] The elastic member 22 is fixed so as to cover the vehicle body side surface of the core metal 21, and comprises an elastic member disc portion 22a and an elastic member cylindrical portion 22b including a portion that wraps around the end of the core metal cylindrical portion 21b, corresponding to each part of the core metal 21, and an axial lip piece 27a and two radial lip pieces 27b are formed to protrude from the inner diameter side of the elastic member disc portion 22a.

[0030] Thus, the seal lip member 20 is formed by fixing the core metal 21 and the elastic member 22 together so that they overlap in the axial direction.

[0031] The slinger 30 is made of metal or a hard synthetic resin material and comprises a slinger cylindrical portion 31 and a slinger disc portion 32, and has a roughly L-shape. When the slinger 30 is mounted on the bearing device 1, the slinger cylindrical portion 31 is positioned to fit (externally fit) onto the inner ring member 3.

[0032] When both the seal lip member 20 and the slinger 30 are mounted on the bearing device 1, the axial lip piece 27a of the seal lip member 20 elastically contacts the inner surface of the slinger disc portion 32, and the two radial lip pieces 27b elastically contact the outer diameter surface of the slinger cylindrical portion 31. Due to the relative rotation of the outer ring member 2 and the inner ring member 3, each lip piece performs a relative sliding contact operation with respect to the target surface.

[0033] Next, the magnetic encoder 40A according to the first embodiment will be described with reference to Figures 2(a) to (c).

[0034] The magnetic encoder 40A consists of a mounting portion 42 and a main body portion 41, both made of magnetic rubber 45, and does not include a core material 46 like the magnetic encoder 40B described later in Figures 3 to 5. In other words, the magnetic encoder 40A as a whole is flexible and stretchable, and is capable of elastic deformation.

[0035] As described above, a groove 2e is formed on the axial end face 2d of the outer ring member 2 (outer ring 2b in the example of Figure 2(a)), which is the rotating member 2, and the magnetic encoder 40A is formed in a T-shape in cross-section so as to fit into the groove 2e.

[0036] The magnetic rubber 45 constituting the magnetic encoder 40A is a ring-shaped magnet made of magnetic rubber 45 formed by kneading magnetic powder into a rubber material. The magnetic encoder 40A is a ring-shaped magnet in which many N poles and S poles are alternately magnetized along its circumferential direction, and a magnetic sensor 15 (see Figure 1) positioned opposite the main body 41 of the magnetic encoder 40 acts to detect magnetic changes accompanying the rotation of the ring-shaped magnet.

[0037] The magnetic encoder 40A can be detachably attached to the groove 2e of its mounting portion 42. Alternatively, the magnetic encoder 40A may be fixed to the groove 2e with an adhesive or the like.

[0038] Since the magnetic encoder 40A is elastic, it is desirable that the mounting portion 42 be fitted into the groove 2e by press-fitting to ensure a tighter fit and prevent it from coming loose. As shown in the figure, it is desirable that the magnetic encoder 40A be mounted so that not only does the flange portion 41b of the main body portion 41 abut or tightly adhere to the outer surface of the outer ring 2b, but the end face of the mounting portion 42 abuts or tightly adheres to the groove bottom 2ec of the groove 2e.

[0039] Furthermore, since the magnetic encoder 40A is expandable and contractible, the diameter of the magnetic encoder 40A may be made smaller than the diameter of the groove 2e to allow it to be mounted in an externally fitted state when extended, in order to ensure a more secure attachment. In this case, a gap may be created between the groove wall 2ea, which is not the mating surface, and the mounting portion 42.

[0040] Furthermore, the fitting of the mounting portion 42 into the groove 2e does not necessarily have to be press-fit; if it has low elasticity, it may be fitted (internal fitting) into the groove wall 2ea on the outer diameter side of the groove 2e. In these cases, a gap may be created between the groove wall 2eb, groove bottom 2ec, which is not the fitting surface, and the mounting portion 42.

[0041] This magnetic encoder 40A has flanges 41b on both radial sides in a T-shape, so that the detection surface for the magnetic sensor 15 can be made wider regardless of the width dimension (radial dimension) of the groove 2e.

[0042] Furthermore, as shown in Figures 2(b) and 2(c), a mounting structure may be provided in which a retaining projection 42b is provided on the contact surface 42a of the recessed groove 2e of the mounting portion 42 with respect to the groove wall 2ea, and an engaging groove 2ed is provided on the groove wall 2ea of ​​the recessed groove 2e. With such a mounting structure, the retaining projection 42b engages with the engaging groove 2ed, thereby preventing the magnetic encoder 40A from coming loose or falling out.

[0043] In Figure 2(b), both the retaining projection 42b and the engagement groove 2ed are semicircular in cross-sectional view, and there is a projection 2ee on the opening side of the engagement groove 2ed. Therefore, the mounted magnetic encoder 40A will not easily come off unless force is applied. The retaining projection 42b is semicircular, and its convex curved surface serves as a curved surface for mounting and detachment guidance, so mounting and detachment (attaching and detaching) is possible if force is applied.

[0044] In Figure 2(c), the retaining projection 42b protrudes midway through the axial direction of the mounting portion 42, and a guide surface 42ba is formed by sloping downward toward the axially inward direction of the mounting portion 42, while a locking surface 42bb is formed on the axially outward side, substantially parallel to the surface of the groove bottom 2ec. On the other hand, the engagement groove 2ed is a rectangular groove in cross-section, and its depth dimension is greater than the protruding dimension of the retaining projection 42b.

[0045] Due to this shape, the mounting portion 42 can be easily attached to the groove 2e by the guide surface 42ba, while the mounting portion 42 cannot be easily attached or detached because the locking surface 42bb locks with the protrusion 2ee. Furthermore, due to the locking between the locking surface 42bb and the protrusion 2ee, there is virtually no possibility of the magnetic encoder 40A coming loose or falling off unintentionally.

[0046] Alternatively, a mounting structure may be used in which a mounting part 42 with a retaining projection 42b, as shown in Figures 2(b) and 2(c), is attached to a recessed groove 2e in which an engagement groove 2ed is not formed in the groove wall 2ea, as shown in Figure 2(a). When the mounting part 42 is attached to the recessed groove 2e, the retaining projection 42b deforms and elastically contacts the groove wall 2ea, thereby suppressing the natural detachment or falling out of the magnetic encoder 40A.

[0047] The retaining projection 42b may be continuous in the circumferential direction, or it may be discontinuous in the circumferential direction, for example, hemispherical. Furthermore, the retaining projection 42b may be provided on the radial outer surface of the mounting portion 42, as shown in Figures 2(b) and 2(c), on the radial inner surface, or on both sides.

[0048] Next, several examples of the magnetic encoder 40B according to the second embodiment will be described with reference to Figures 3 to 5. Each of these magnetic encoders 40B has an annular core material 46 made of metal, with magnetic rubber 45 fixed to the core material 46, and, like the one in Figure 1, has a mounting portion 42 and a main body portion 41 with a flange portion 41b. These can be molded by insert molding.

[0049] In all of the magnetic encoders 40B shown in Figures 3 to 5, the core material 46 is arranged to span from the mounting portion 42 to the main body portion 41, and the outer axial portion, that is, the surface portion 41a facing the magnetic sensor 15, is formed of magnetic rubber 45. The shape and dimensions of the groove 2e and the axial projection dimension of the main body portion 41 are the same for all examples in Figures 3 to 5.

[0050] Furthermore, the radial projection dimension of the flange portion 41b in the main body portion 41 is the same for Figures 3(a) to (c), Figures 4(a) and (b), and Figure 5(a) and (b), while the projection dimension in Figure 4(c) and (d) is larger than that of the others.

[0051] The core material 46 may be made of a hard synthetic resin material, and for example, the magnetic encoder 40B may be molded by two-color molding. Also, for example, the magnetic encoder 40B in Figures 3(b) and 3(c) may be formed by forming the core material 46 and the magnetic rubber 45 separately and then bonding them together.

[0052] Thus, since the magnetic encoder 40B is constructed including an annular core material 46, it is easy to maintain its annular shape, and therefore easy to install into the groove 2e. In particular, because the mounting portion 42 includes the core material 46, deformation of the mounting portion 42 can be suppressed when installing into the groove 2e, allowing for smooth installation.

[0053] Furthermore, since the core material 46 extends from the mounting portion 42 to the main body portion 41, separation of the main body portion 41 and the mounting portion 42 can be suppressed. For example, the main body portion 41 exposed on the surface after mounting the magnetic encoder 40B can be prevented from falling off.

[0054] Next, we will sequentially describe the three examples shown in Figure 3, the four examples shown in Figure 4, and the two examples shown in Figure 5, which are included in this embodiment.

[0055] In all of the magnetic encoders 40B shown in Figures 3(a) to 3(c), the overall cross-sectional shape is such that the radial centerline is the dashed line in the figure of the mounting portion 42 (see Figures 3(a) to 3(c)), and not only the external shape but also the internal structure is symmetrical in the radial direction between the outer and inner parts.

[0056] In the magnetic encoder 40B shown in Figure 3(a), a core material 46 with a rectangular cross-section is positioned in the center in the radial direction, with its long side extending from the mounting portion 42 to the main body portion 41 (it is housed inside), and magnetic rubber 45 is arranged around its entire circumference. In short, the core material 46 is not exposed at all in the circumferential direction and is covered by the magnetic rubber 45.

[0057] In the magnetic encoder 40B shown in Figures 3(b) and 3(c), the core material 46 is arranged so as to be in contact with the outer ring 2b. Specifically, the fitting surface that contacts the inner surface of the groove 2e is exposed, and the core material 46 is arranged in the area including this fitting surface and in the area including the surface of the flange portion 41b on the mounting portion 42 side.

[0058] The core material 46 is generally T-shaped, with flange pieces 46b on both radial sides. In Figure 3(b), a groove 46a is formed on the outer surface in the axial direction, and a T-shaped magnetic rubber 45 having a protrusion 45a is fixed to the outer surface including the groove 46a. On the other hand, in Figure 3(c), there is no groove on the outer surface in the axial direction, and the magnetic rubber 45 is fixed to the outer plane of the T-shaped core material 46.

[0059] These magnetic encoders 40B have a symmetrical shape between their radial outer and inner portions, making them stable and resistant to deformation. Furthermore, the core material 46 and magnetic rubber 45 in Figures 3(a) and 3(b) are less likely to separate. In particular, the one in Figure 3(a) poses almost no risk of the two materials separating.

[0060] Furthermore, as mentioned above, the structures shown in Figures 3(b) and 3(c) may consist of a core material 46 and magnetic rubber 45 that are individually formed, or the core material 46 and magnetic rubber 45 may be bonded together with an adhesive. In particular, the structure shown in Figure 3(b), in which the core material 46 has concave ridges 46a and the magnetic rubber 45 has convex ridges 45a, forms a strong bonding relationship.

[0061] In all of the magnetic encoders 40B shown in Figures 4(a) to 4(d), a core material 46 is positioned radially on the outside or inside of the mounting portion 42, and the core material 46 has an exposed fitting surface that contacts the inner surface of the groove 2e. The core material 46 is provided with a flange piece 46b that extends to the flange portion 41b of the main body portion 41 and is roughly L-shaped.

[0062] In the magnetic encoder 40B shown in Figure 4(a), the core material 46 is covered with magnetic rubber 45 on all surfaces except for the groove bottom 2ec of the groove 2e, the groove wall 2ea on the outer diameter side, and the end face 2d of the rotating member 2 on the vehicle body side. The mounting portion 42 is shaped so that its entire radial length fits into the groove, and it consists of layers of core material 46 and magnetic rubber 45 from the outer diameter side. The main body portion 41 has a flange portion 41b only on the outer diameter side, and a flange piece 46b of the core material 46, which is continuous from the mounting portion 42 side, is arranged on a part of the flange portion 41b on the mounting portion 42 side.

[0063] The magnetic encoder 40B in Figure 4(b) is radially symmetrical to that in Figure 4(a). In other words, the magnetic encoder 40B is mounted in the groove 2e such that the approximately L-shaped core material 46 contacts the groove wall 2eb on the inner diameter side of the groove 2e.

[0064] In the magnetic encoder 40B shown in Figure 4(c), the core material 46 is covered with magnetic rubber 45 on all surfaces except the groove bottom 2ec of the groove 2e, the groove wall 2ea on the outer diameter side, the surface that contacts the end face 2d of the rotating member 2 on the vehicle body side, and the inner diameter side surface. The mounting portion 42 is shaped so that the core material 46 is mounted in the groove 2e, and the main body portion 41 has a flange portion 41b only on the outer diameter side, and a flange piece 46b of the core material 46 that is continuous from the mounting portion 42 side is arranged on a part of the flange portion 41b on the mounting portion 42 side. In addition, the inner diameter side surface of the core material 46 is exposed when fitted into the groove 2e.

[0065] The magnetic encoder 40B in Figure 4(d) is radially symmetrical to that in Figure 4(c). In other words, the magnetic encoder 40B is mounted in the groove 2e such that the approximately L-shaped core material 46 contacts the groove wall 2eb on the inner diameter side of the groove 2e.

[0066] Comparing the magnetic encoder 40B in Figure 4(a) and the magnetic encoder 40B in Figure 4(c), it is desirable that the core material 46 in the mounting portion 42 be fitted (internally fitted) into the groove wall 2ea on the outer diameter side in both cases. In the case of Figure 4(a), since the mounting portion 42 contains magnetic rubber 45, internal fitting is not necessary, and the mounting structure may be such that the entire mounting portion 42 is press-fitted into the groove 2e. In the case of Figure 4(c), internal fitting of the core material 46 is essential.

[0067] Similarly, in the case of Figure 4(b), the core material 46 does not necessarily have to be externally fitted into the groove wall 2eb on the inner diameter side; the entire mounting portion 42 may be press-fitted into the groove 2e. In the case of Figure 4(c), external fitting of the core material 46 is essential.

[0068] The components shown in Figures 4(a) and 4(b) can be mounted by fitting them into the inner diameter groove wall 2ea or the outer diameter groove wall 2eb of the recessed groove 2e, thus maintaining a stable mounting state. Furthermore, the components shown in Figures 4(c) and 4(d) require less core material 46 and magnetic rubber 45, thus reducing manufacturing costs.

[0069] The magnetic encoder 40B in Figures 5(a) and 5(b) has the same external shape as that in Figures 4(a) and 4(b), but the position and shape of the core material 46 differ from those in Figures 4(a) and 4(b). In Figure 5(a), the core material 46, which has a rectangular cross-section, is positioned on the inner diameter side, while in Figure 5(b), the core material 46, which has a rectangular cross-section, is positioned on the outer diameter side.

[0070] Therefore, in the case of Figure 5(a), it is desirable that the core material 46 in the mounting portion 42 is fitted (externally fitted) into the inner diameter groove wall 2eb, and in the case of Figure 5(b), it is desirable that the core material 46 in the mounting portion 42 is fitted (internally fitted) into the outer diameter groove wall 2ea. However, these do not necessarily have to be externally fitted or internally fitted; the entire mounting portion 42 may be press-fitted into the recessed groove 2e.

[0071] Comparing the above examples, in the three examples of Figure 3, since the flange portion 41b is formed on both radial sides, the radial width dimension of the magnetic encoder 40B can be increased regardless of the radial width dimension of the groove 2e, and a sufficient magnetic flux density can be obtained for detection by the magnetic sensor 15.

[0072] Furthermore, by increasing the radial projection of the flange portion 41b of the magnetic encoder 40B, the radial dimension of the main body portion 41 can be increased, thereby also increasing the magnetic flux density. Therefore, even if the flange portion 41b is formed on only one radial side (Figures 4(a) to (d), Figures 5(a) and (b)), the magnetic flux density can be increased depending on the dimensions.

[0073] In particular, in the cases shown in Figures 4(c) and 4(d), the radial dimension of the mounting portion 42 is small, and the flange portion 41b is formed on only one side. However, by making the radial projection dimension of the flange portion 41b larger than that of Figures 4(a) and 4(b), the radial width dimension of the magnetic encoder 40B is not reduced.

[0074] Furthermore, in Figures 3(a), 4(a)(b), and 5(a)(b), the mounting portion 42 is mounted so that the magnetic rubber 45 contacts the groove 2e. Since the mounting portion 42 does not need to be mounted to the groove 2e by fitting (internal or external) the core material 46, the allowable range of error in the diameter of the mounting portion 42 can be increased compared to the case where only the core material 46 is mounted to the groove 2e (Figures 3(b)(c), 4(c)(d)).

[0075] As described above, the magnetic encoder 40B including the core material 46 may be formed to include core material 46 of various cross-sectional shapes, and may also include core material 46 of various other cross-sectional shapes.

[0076] The multiple embodiments described above are examples in which the rotating member 2 to which the magnetic encoders 40A and 40B are attached is an outer ring member 2, but they can also be applied to examples in which the rotating member 2 is an inner ring member 3. In the case of the bearing device 1 in which the outer ring member 2 is the rotating member 2, the diameter dimensions of the magnetic encoders 40A and 40B naturally become larger, so the pole width in the circumferential direction also becomes larger, and the detection accuracy by the magnetic sensor 15 is improved.

[0077] Furthermore, in the above embodiment, the magnetic encoders 40A and 40B are mounted in grooves 2e provided on the outer ring 2b of the outer ring member 2. However, the grooves 2e may also be provided on the end face 2aa (see Figure 1) of the hub ring 2a of the outer ring member 2, and the magnetic encoders 40A and 40B may be mounted in these grooves 2e.

[0078] Furthermore, since the magnetic encoders 40A and 40B described above are designed to be mounted on grooves 2e provided in the rotating member 2, it is sufficient to match the dimensions of the grooves 2e with the dimensions of the mounting portion 42 of the magnetic encoders 40A and 40B, thus allowing them to be applied to various bearing devices 1.

[0079] As described above, the magnetic encoders 40A and 40B can be mounted in various positions as long as a groove 2e is provided on the rotating member 2, thus improving the degree of freedom in the mounting positions of the magnetic encoders 40A and 40B and the magnetic sensor 15.

[0080] The configurations and shapes of the magnetic encoders 40A and 40B described above according to multiple embodiments are merely examples, and it goes without saying that configurations and shapes other than those shown in the figures can be changed as appropriate.

[0081] The magnetic encoders 40A and 40B described above are positioned as components of a sealing device 11, attached to the sealing member 18 in a separate state, or as components of a bearing device 1, attached to the outer ring member 2. [Explanation of Symbols]

[0082] 1. Bearing device 2. Rotating member (outer ring member) 2a Hub wheel 2aa End face of hub wheel 2b Outer ring 2d End face on the vehicle body side (axial direction) 2e Concave groove 2ea (outer diameter side) groove wall 2eb (inner diameter side) groove wall 2ec groove bottom 2ed engagement groove 3. Fixing member (inner ring member) 3a Inner ring 10 Sealed space 11 Sealing device 15 Magnetic Sensor 18 sealing member 20 Seal lip member 21 Mandrel 21a Core metal disc section 21b Core metal cylinder 22 Elastic members 22a Elastic member disc portion 22b Elastic member cylindrical part 27 Lip section 30 Slinger 31 Slinger cylindrical section 32 Slinger disc section 40A, 40B Magnetic Encoder 41 Main body 41a Surface part 41b Tsubabe 42 Mounting part 42a Contact surface 42b Retaining projection 45 Magnetic rubber 46 Core material

Claims

1. A magnetic encoder mounted on the rotating member in a bearing device comprising a fixed member and a rotating member that rotates coaxially with respect to the fixed member, wherein the bearing device has a mounting space between the fixed member and the rotating member for which a sealing member is attached, A groove is formed on the axial end face of the rotating member, having groove walls on both radial sides. A magnetic encoder characterized by comprising: a mounting portion that can be attached to the groove and is formed separately from the sealing member, and which is mounted in the groove; and a main body portion that is connected to the mounting portion and has a flange portion that abuts against at least one end face adjacent to the groove in the radial direction.

2. In claim 1, The magnetic encoder is characterized in that the mounting portion is shaped so that its axial end face abuts against the bottom of the groove.

3. In claim 1, A magnetic encoder characterized in that a retaining projection is formed on the contact surface of the mounting portion with the groove wall of the recessed groove.

4. In claim 1, A magnetic encoder characterized in that both the mounting portion and the main body portion are made of magnetic rubber.

5. In claim 1, A magnetic encoder characterized in that a core material is arranged from the mounting portion to the main body portion, and magnetic rubber is arranged on at least the outer side of the core material in the axial direction.

6. A bearing device comprising a fixed member, a rotating member, and a magnetic encoder as described in claim 1.

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