Hub unit bearing with sensor

Abstract

To provide a hub unit bearing with a sensor which prevents influence of warpage and deformation of a sensor housing part on sensor installation errors and inhibits occurrence of vibration of a sensor flange and a sensor to achieve high detection accuracy.SOLUTION: In a cap 30 with a sensor holder, a sensor housing part 54 capable of housing a sensor 70 and a nut holding part 57 which holds a nut 60 fixing a sensor flange 72 are formed protruding from a bottom plate part 53 to the inboard side. An inboard side end surface 57a of the nut holding part 57 or an inboard side end surface 60a of the nut 60 protrude to the inboard side of an inboard side end surface 54a of the sensor housing part 54. The inboard side end surface 54a of the sensor housing part 54 has slit-like recessed parts 56 extending in a radial direction. A sensor fixing member 80 is provided between the inboard side end surface 54a of the sensor housing part 54, which includes the recessed parts 56, and the sensor flange 72.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a sensor-equipped hub unit bearing used to rotatably support an automobile wheel relative to a suspension system. [Background technology]

[0002] Conventionally, there is known a wheel bearing device that rotatably supports the wheels in the suspension of an automobile, etc. Some wheel bearing devices are equipped with a rotation speed detection device that detects the rotation speed of the wheels in order to control an antilock brake system (ABS).

[0003] For example, in the bearing device 100 described in Patent Document 1, as shown in Fig. 8, the sensor support part 110 and the nut holding part 120 are formed separately from each other, and the end face 121 of the nut holding part 120 protrudes axially inward from the end face 111 of the sensor support part 110. The rotation sensor 115 is supported by the sensor support part 110, abuts against the end face 121 of the nut holding part 120 via a sensor flange 122 provided on the rotation sensor 115, and is fixed to a nut 124 held by the nut holding part 120 by a fastening bolt 123. As a result, even if the sensor support part 110 is warped or the sensor holder is deformed, the attitude of the rotation sensor 115 can be suppressed from tilting, and the influence on the reading performance of the rotation sensor 115 can be prevented. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2023-29117 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, according to the sensor-equipped wheel bearing device 100 described in Patent Document 1, one end of the sensor flange 122 for fixing the rotation sensor 115 is fixed in contact with the end face 121 of the nut holding part 120 by one fastening bolt 123, and an axial gap C is provided between the end face 111 of the sensor support part 110. That is, since the sensor flange 122 has a cantilever structure with a long radial distance L from the fastening bolt 123 to the rotation sensor 115, when the bolt vibrates due to vibration from the tire, the rotation sensor 115 is likely to move (vibrate) like a woodpecker. In addition, when the vibration occurs, the axial distance between the encoder and the sensor 115 changes continuously, which may adversely affect the reading performance of the sensor 115. In particular, in the case of the structure shown in Figure 8, a slit 113 extending to the bottom surface 110a of the sensor support part 110 is provided on the line connecting the center of the sensor insertion hole 112 and the center of the female threaded hole 124a of the nut 124, and the sensor support part 110 is formed of a pair of semi-cylindrical parts, and the sensor 115 is not held in the part of the slit 113, so that the above-mentioned vibration is easily exacerbated.

[0006] The present invention has been made in consideration of the above-mentioned problems, and its purpose is to provide a sensor-equipped hub unit bearing with high detection accuracy, which prevents the effects on sensor installation errors caused by warping of the sensor accommodating portion and deformation of the sensor holder cap, and suppresses the generation of vibrations in the sensor flange and, ultimately, the sensor. [Means for solving the problem]

[0007] Therefore, the above object of the present invention can be achieved by the following configuration [1] relating to a sensor-equipped hub unit bearing. [1] An outer member having a double row outer ring raceway on an inner circumferential surface thereof; an inner member having a double row inner ring raceway on an outer circumferential surface thereof facing the double row outer ring raceway; A plurality of rolling elements are arranged to roll freely between the double row inner ring raceways and the double row outer ring raceways; a magnetic encoder fixed to an inboard end of the inner member; a cap with a sensor holder that is fitted and fixed to an inboard end of the outer member, closes an opening on the inboard side of the outer member, and holds a sensor that detects displacement of the magnetic encoder; A sensor-equipped hub unit bearing comprising: the sensor holder cap is formed integrally with a sensor accommodating portion having an accommodating hole capable of accommodating the sensor such that the sensor faces the magnetic encoder, and a nut holding portion for holding a nut for fixing a sensor flange provided on the sensor, the sensor accommodating portion and the nut holding portion being protruded from a bottom plate portion of the sensor holder cap toward the inboard side, an inboard end face of the nut holding portion or an inboard end face of a nut fixed to the nut holding portion protrudes inboard further than the inboard end face of the sensor accommodating portion, an inboard end surface of the sensor accommodating portion has at least one recess extending radially from the accommodating hole; a sensor fixing member is provided between an inboard end surface of the sensor accommodating portion, the inboard end surface including the recess, and the sensor flange; Hub unit bearing with sensor. Effect of the Invention

[0008] The sensor-equipped hub unit bearing of the present invention prevents the effects of warping of the sensor accommodating portion and deformation of the sensor holder cap on sensor installation errors, and suppresses vibrations in the sensor flange, i.e., the sensor, thereby improving the detection accuracy of the magnetic encoder. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a cross-sectional view of a sensor-equipped hub unit bearing according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a cross-sectional view of a main part of the cap to which the sensor of FIG. 1 is attached. [Diagram 3] 3(a) is an enlarged cross-sectional view of a main part of the cap shown in FIG. 1, and FIG. 3(b) is a view taken along the line III in FIG. 3(a). [Figure 4] FIG. 4(a) is an enlarged cross-sectional view of a main part of a cap according to a modification of the first embodiment, and FIG. 4(b) is a view taken along the line IV in FIG. 4(a). [Diagram 5] FIG. 5 is a cross-sectional view of a sensor-equipped hub unit bearing according to a second embodiment of the present invention. [Figure 6] 6(a) is an enlarged cross-sectional view of a main part of the cap shown in FIG. 5, and FIG. 6(b) is a view taken along the line VI in FIG. 6(a). [Figure 7] FIG. 7(a) is an enlarged cross-sectional view of a main part of a cap according to a modification of the second embodiment, and FIG. 7(b) is a view taken along the line VII in FIG. 7(a). [Figure 8] FIG. 8 is a cross-sectional view of a main portion of a conventional sensor-equipped hub unit bearing. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] [First embodiment] A sensor-equipped hub unit bearing (hereinafter also simply referred to as a hub unit bearing) according to a first embodiment of the present invention will be described in detail with reference to FIGS. 1 to 3. FIG. In relation to the hub unit bearing, throughout this specification and the claims, the "inboard side" refers to the vehicle body side of the hub unit bearing when mounted on the vehicle body, the right side in Fig. 1, and is also referred to as the inside. The "outboard side" refers to the wheel side of the hub unit bearing when mounted on the vehicle body, the left side in Fig. 1, and is also referred to as the outside.

[0011] As shown in FIG. 1, the sensor-equipped hub unit bearing 1 of this embodiment is a hub unit bearing for a driven wheel, and mainly comprises an outer ring 2 as an outer member, a hub 3 as an inner member, a number of rolling elements 4, 4, a magnetic encoder 14, and a cap 30 with a sensor holder (hereinafter also simply referred to as the cap).

[0012] The outer ring 2 has a stationary flange 7 on its outer peripheral surface and double-row (two-row) outer ring raceways 8a, 8b on its inner peripheral surface. When in use, the stationary flange 7 is fixed to a knuckle of a suspension device so that the outer ring 2 does not rotate while being supported by the suspension device.

[0013] The hub 3 is made up of a hub axle 9 and an inner ring 10 that is fitted onto the hub axle 9 and fixed by crimping, and is disposed coaxially (concentrically) with the outer ring 2 on the radially inner side of the outer ring 2.

[0014] The hub axle 9 is provided with a circular wheel mounting flange 11 that extends radially outward from a portion that protrudes axially outward from the axially outer (outboard side) opening of the outer ring 2 and is used to support and fix a wheel (driven wheel) and rotating braking members such as a disc rotor. Specifically, the wheel mounting flange 11 is provided with a plurality of insertion holes 11a, and a hub bolt 17 is serrated-fitted into each of the insertion holes 11a. Note that the plurality of insertion holes 11a in the wheel mounting flange 11 can also be made into female-threaded holes, and a hub bolt can be screwed into them to support and fix a wheel and rotating braking members such as a disc rotor.

[0015] Additionally, an inner ring raceway 12a of the outboard side row (one row) is provided on a portion of the outer peripheral surface of the hub axle 9 that faces the outer ring raceway 8a of the axially outer (outboard side) row of the outer ring 2. Additionally, a small diameter step 13 is provided on an axially inner end of the outer peripheral surface of the hub axle 9 that faces the outer ring raceway 8b of the axially inner (inboard side) row of the outer ring 2. The hub axle 9 also has a crimping portion 24 that partially constitutes the outer peripheral surface of the small diameter step 13, and whose inboard end deforms radially outward to crimp and fix the inner ring 10.

[0016] An inner ring raceway 12b of the inboard side row (the other row) is provided on the outer circumferential surface of the inner ring 10. The inner ring 10 is fitted onto the small diameter step 13 of the hub axle 9 with its outboard end face abutting against the step surface of the small diameter step 13, and is fixed to the hub axle 9 by crimping a crimp portion 24 formed by deforming the inboard end of the small diameter step 13 radially outward.

[0017] The rolling elements 4, 4 are freely rollable while being held by a pair of retainers 6, 6 in the portion between the outer ring raceway 8a and the inner ring raceway 12a of the outboard row, and between the outer ring raceway 8b and the inner ring raceway 12b of the inboard row.

[0018] A seal ring 5 is supported and fixed to the outboard end of the inner peripheral surface of the outer ring 2. The seal ring 5 closes the axial outer end opening of an internal space 18 in which a plurality of rolling elements 4, 4 are provided, which is present between the inner peripheral surface of the outer ring 2 and the outer peripheral surface of the hub axle 9. The seal ring 5 comes into sliding contact with a large diameter step 20 of the outer peripheral surface of the hub axle 9, which is on the outboard side of the inner ring raceway 12a.

[0019] An annular magnetic encoder 14 is supported and fixed to the outer circumferential surface of the inboard end of the inner ring 10. The magnetic encoder 14 is composed of a support ring 26 and an encoder body 27. The support ring 26 is formed into an annular shape with an L-shaped cross section by pressing a magnetic metal plate, such as a ferritic stainless steel plate such as SUS430 or a rolled steel plate such as SPCC. The outboard portion of the support ring 26 is fitted and fixed to the outside of the inner ring 10.

[0020] The encoder body 27 is made into a circular ring shape using a permanent magnet made of a magnetic material such as ferrite powder mixed into rubber or thermoplastic resin, and is attached and fixed to the inboard side of the circular portion of the support ring 26 that is bent radially inward. The inboard side (detection surface) of the encoder body 27 is magnetized with S poles and N poles alternately and at equal pitch in the circumferential direction.

[0021] Referring also to FIG. 3, a cylindrical cap 30 with a bottom is fixed to the inboard end of the outer ring 2 to close the inboard opening of the outer ring 2.

[0022] The cap 30 has a metal core 40 and a synthetic resin cap body 50. The cap body 50 is made into a cylindrical shape with a bottom as a whole by injection molding (axial draw molding) of synthetic resin, and includes a cylindrical portion 51 for fixing the core 40, and a bottom plate portion 53 that extends from the inboard end face of the cylindrical portion 51 to the inner diameter side and closes the inboard opening of the cylindrical portion 51.

[0023] The synthetic resin material constituting the cap body 50 is, for example, a fiber-reinforced polyamide resin material obtained by compounding polyamide 66 resin with glass fiber, carbon fiber, or metal fiber as a fibrous reinforcing material. If necessary, water resistance may be further improved by appropriately adding amorphous aromatic polyamide resin (modified polyamide 6T / 6I) or low water absorption aliphatic polyamide resin (polyamide 11 resin, polyamide 12 resin, polyamide 610 resin, polyamide 612 resin) to the polyamide resin.

[0024] The core bar 40 is made of metal such as stainless steel plate or rolled steel plate, has an L-shaped cross section, and is formed into an annular shape as a whole. An inboard side portion of the core bar 40 is joined and fixed to a cylindrical portion 51. That is, a flange portion 41 provided so as to be bent radially outward from the inboard side end of the core bar 40 is molded and fixed inside the cylindrical portion 51 of the cap body 50. An outboard side portion of the core bar 40 is press-fitted into the inboard side end of the inner peripheral surface of the outer ring 2 via a part of the cylindrical portion 51 formed on the outer peripheral surface of the core bar 40.

[0025] The bottom plate portion 53 is configured to be generally disc-shaped as a whole. A sensor accommodating portion 54 and a nut holding portion 57 are formed on an inboard end surface 53a of the bottom plate portion 53 so as to protrude toward the inboard side. As shown in Fig. 3(b), the sensor accommodating portion 54 and the nut holding portion 57 are integrated and formed into a generally oval shape in a side view. The inboard end surface 54a of the sensor accommodating portion 54 and the inboard end surface 57a of the nut holding portion 57 are at the same height.

[0026] A substantially cylindrical accommodation hole 55 capable of accommodating the sensor 70 is provided penetrating the sensor accommodation portion 54 in the axial direction, facing the encoder body 27 of the magnetic encoder 14. The inner diameter dimension of the accommodation hole 55 is slightly larger than the outer diameter dimension of the sensor 70. This prevents the sensor accommodation portion 54 from being warped or the cap 30 from being deformed, thereby preventing the mounting position of the sensor 70 from being affected, and prevents the reading performance of the magnetic encoder 14 by the sensor 70 from being affected.

[0027] An insert nut 60 is molded and fixed to the nut holding portion 57. The insert nut 60 has an internal thread 61 formed on its inner circumferential surface. An inboard end face 60a of the insert nut 60 protrudes inboard further than the inboard end face 54a of the sensor accommodating portion 54. That is, a step C is provided between the inboard end face 60a of the insert nut 60 and the inboard end face 54a of the sensor accommodating portion 54 (see FIG. 3).

[0028] Furthermore, the inboard end surface 54a of the sensor accommodating portion 54 is provided with a plurality of (six in FIG. 3) slit-shaped recesses 56 that extend radially from the accommodating hole 55 as a center and penetrate in the radial direction. The recesses 56 are formed to avoid the line connecting the center of the accommodating hole 55 and the center of the insert nut 60. The recesses 56 are intended to discharge excess portions of a sealing member (sealant) 80 that serves as a sensor fixing member and is applied to fix a sensor 70 (described later) to the sensor accommodating portion 54. In addition, the slit-shaped recess 56 in this embodiment is formed in the inboard end face 54a of the sensor accommodating portion 54 in order to discharge the excess portion of the sealing member 80, and does not need to be formed deep in the axial direction, and the depth of the recess 56 is, for example, 1 / 3 or less of the axial depth of the accommodating hole 55.

[0029] The sensor 70 includes a sensor body 71 and a sensor flange 72 fixed approximately perpendicular to the sensor body 71. The sensor 70 is attached to the sensor accommodating portion 54 by applying a sealing material 80 to the inner corner between the sensor body 71 and the outboard end face 72a of the sensor flange 72, inserting the sensor body 71 into the accommodating hole 55, and screwing a bolt 75 inserted into a bolt hole 73 provided at one end of the sensor flange 72 into the female thread 61 of the insert nut 60 to fix the sensor 70 in place.

[0030] As a result, the sealing material 80 applied to the sensor 70 fills the gap (step) C between the inboard end face 54a of the sensor accommodating portion 54, including the recess 56, and the outboard end face 72a of the sensor flange 72, and part of it also fills the gap between the sensor main body 71 and the accommodating hole 55.

[0031] Then, excess sealing member 80 flows radially within recess 56 and is discharged to the outside. Sealing member 80 hardens into a rubber-like state over time, and is not affected even if sensor accommodating portion 54 warps or cap 30 deforms, and serves as a sensor fixing member to fix sensor 70 to sensor accommodating portion 54 without being affected by this, i.e., without applying any load to sensor 70. Furthermore, since the sealing member 80 has elasticity when hardened, it acts to absorb vibrations of the sensor flange 72 even if the sensor flange 72 comes into contact with the sealing member 80 due to vibrations from the tire.

[0032] Generally, the resin sensor accommodating portion 54 and sealing member 80 do not adhere or are difficult to adhere to, but when the sealing member 80 hardens not only into the gap C between the sensor flange 72 and the inboard end face 54a of the sensor accommodating portion 54, but also into the recess 56, the hardened convex portion within the recess 56 engages with the recess 56, and the sensor 70 is securely fixed to the sensor accommodating portion 54.

[0033] In the above embodiment, since the sealing member 80, which has hardened into a rubber-like material, has a sealing function, the accommodating hole 55 is a through hole. However, the function of the sealing member 80 can be specialized to fixing the sensor 70 by making the accommodating hole 55 a bottomed hole or by forming an O-ring groove in the sensor body 71 or the accommodating hole 55 and attaching an O-ring thereto.

[0034] As described above, the sensor-equipped hub unit bearing 1 of this embodiment prevents the effects of warping of the sensor accommodating portion 54 and deformation of the cap 30 on sensor installation errors, and by fixing the sensor 70 to the sensor accommodating portion 54 with the sealing member 80, the generation of vibrations in the sensor 70 can be suppressed, improving the reading and detection accuracy of the magnetic encoder 14. In particular, since the recess 56 is located at a position other than on the line connecting the center of the sensor accommodating portion 54 and the center of the nut holding portion 57, vibration of the sensor flange 72, i.e., the sensor 70, can be further suppressed, improving the detection accuracy of the sensor 70.

[0035] [Modification of the first embodiment] FIG. 4(a) is an enlarged cross-sectional view of a main portion of a cap of a sensor-equipped hub unit bearing according to a modified example of the first embodiment, and FIG. 4(b) is a view taken along the line IV in FIG. 4(a). 4(a) and 4(b), cap 30 of sensor-equipped hub unit bearing 1 of this modified example has sensor accommodating portion 54 and nut retaining portion 57 formed integrally so as to be continuous via constricted portion 58, and is formed in the shape of a figure 8 in side view. In this modified example as well, inboard end face 54a of sensor accommodating portion 54 and inboard end face 57a of nut retaining portion 57 are at the same height.

[0036] The inboard end face 60a of the insert nut 60 fixed by molding to the nut holding portion 57 protrudes inboard further than the inboard end face 54a of the sensor accommodating portion 54. In other words, there is a step C between the inboard end face 60a of the insert nut 60 and the inboard end face 54a of the sensor accommodating portion 54.

[0037] By connecting the sensor accommodating portion 54 and the nut holding portion 57 with the narrowed portion 58 to form an 8 shape in a side view, the length of each recess 56 is shortened and made approximately the same length, in particular the length of the recesses 56a, 56b extending diagonally downward from the center of the accommodating hole 55 toward the center of the insert nut 60 is shortened, which promotes the discharge of excess sealing member 80. As a result, the hardened sealing member 80 is formed uniformly in the circumferential direction, and the sensor 70 can be stably fixed to the sensor accommodating portion 54.

[0038] In addition, by providing a constricted portion 58 at the connection between the sensor accommodating portion 54 and the nut holding portion 57, the thickness of each portion (especially the connection between the sensor accommodating portion 54 and the nut holding portion 57) is made uniform, which prevents the occurrence of sink marks during injection molding and thereby prevents deformation of the sensor accommodating portion 54. Other configurations and operations are similar to those of the sensor-equipped hub unit bearing 1 of the first embodiment.

[0039] [Second embodiment] Next, a sensor-equipped hub unit bearing according to a second embodiment will be described with reference to Figs. 5, 6(a) and 6(b). In the sensor-equipped hub unit bearing 1 of this embodiment, the inboard end face 57a of the nut retaining portion 57 is formed to protrude further inboard than the inboard end face 54a of the sensor accommodating portion 54. In other words, there is a step C between the inboard end face 57a of the nut retaining portion 57 and the inboard end face 54a of the sensor accommodating portion 54. Since the sensor accommodating portion 54 and the nut retaining portion 57 are molded using a single molding die, the dimensions of the step C can be stably formed.

[0040] In this embodiment, the inboard end face 60a of the insert nut 60 is mold-fixed at the same height as the inboard end face 57a of the nut holding portion 57. The height of the inboard end face 60a of the insert nut 60 does not need to be particularly limited, and the inboard end face 60a may protrude from or be recessed into the inboard end face 57a of the nut holding portion 57.

[0041] Furthermore, a plurality of slit-shaped recesses 56 are formed radially from the center of the accommodating hole 55 on the inboard end face 54a of the sensor accommodating portion 54. The recesses 56 are formed to avoid the line connecting the center of the accommodating hole 55 and the center of the nut holding portion 57, and the lengths of the recesses 56 are approximately the same. By making the lengths of the recesses 56 uniform, as in the modified example of the first embodiment, the sealing member 80 is formed uniformly in the circumferential direction, and the sensor 70 can be stably fixed to the sensor accommodating portion 54.

[0042] [Modification of the second embodiment] 7, in the sensor-equipped hub unit bearing 1 of this modified example, the sensor accommodating portion 54 and the nut retaining portion 57 are formed in a substantially cylindrical shape and protrude on the inboard side independently from the inboard side end face 53a of the bottom plate portion 53. Also, the inboard side end face 57a of the nut retaining portion 57 protrudes on the inboard side from the inboard side end face 54a of the sensor accommodating portion 54 by a step C.

[0043] By forming the sensor accommodating portion 54 and the nut holding portion 57 as independent, generally cylindrical shapes, the lengths of the multiple recesses 56 formed in the inboard end face 54a of the sensor accommodating portion 54 become generally the same, and the sealing member 80 is formed uniformly in the circumferential direction, allowing the sensor 70 to be stably fixed to the sensor accommodating portion 54. In addition, the wall thickness of each portion becomes uniform, preventing sink marks during injection molding.

[0044] The present invention is not limited to the above-described embodiments and modifications, but can be modified and improved as appropriate.

[0045] As described above, the present specification discloses the following: (1) an outer member having a double row outer ring raceway on an inner circumferential surface thereof; an inner member having a double row inner ring raceway on an outer circumferential surface thereof facing the double row outer ring raceway; A plurality of rolling elements are arranged to roll freely between the double row inner ring raceways and the double row outer ring raceways; a magnetic encoder fixed to an inboard end of the inner member; a cap with a sensor holder that is fitted and fixed to an inboard end of the outer member, closes an opening on the inboard side of the outer member, and holds a sensor that detects displacement of the magnetic encoder; A sensor-equipped hub unit bearing comprising: the sensor holder cap is formed integrally with a sensor accommodating portion having an accommodating hole capable of accommodating the sensor such that the sensor faces the magnetic encoder, and a nut holding portion for holding a nut for fixing a sensor flange provided on the sensor, the sensor accommodating portion and the nut holding portion being protruded from a bottom plate portion of the sensor holder cap toward the inboard side, an inboard end face of the nut holding portion or an inboard end face of a nut fixed to the nut holding portion protrudes inboard further than the inboard end face of the sensor accommodating portion, an inboard end surface of the sensor accommodating portion has at least one recess extending radially from the accommodating hole; a sensor fixing member is provided between an inboard end surface of the sensor accommodating portion, the inboard end surface including the recess, and the sensor flange; Hub unit bearing with sensor. This configuration prevents the effects of warping of the sensor accommodating portion and deformation of the sensor holder cap on sensor installation errors, and also suppresses vibrations of the sensor flange, i.e., the sensor, improving the detection accuracy of the sensor.

[0046] (2) The recess is located at a position other than on a line connecting the center of the sensor accommodating portion and the center of the nut holding portion. The sensor-equipped hub unit bearing according to (1). According to this configuration, the occurrence of vibrations in the sensor flange, i.e., the sensor, can be further suppressed, improving the detection accuracy of the sensor.

[0047] (3) The sensor fixing member is a sealing member that is inserted between the inboard end surface of the sensor accommodating portion, including the recess, and the sensor flange, and hardens into a rubber-like sealing member. The sensor-equipped hub unit bearing according to (1). According to this configuration, the sensor can be fixed to the sensor containing portion by the hardened sealing member without being affected by warping or deformation of the sensor containing portion. (4) The receiving hole of the sensor receiving portion is formed to have a diameter larger than an outer circumferential surface of the sensor, The sealing member is disposed between the receiving hole and an outer circumferential surface of the sensor. The sensor-equipped hub unit bearing according to (3). According to this configuration, the occurrence of vibrations in the sensor flange, i.e., the sensor, can be further suppressed, improving the detection accuracy of the sensor.

[0048] (5) The sensor accommodating portion and the nut holding portion are integrally formed so as to be continuous with each other via a constricted portion. A sensor-equipped hub unit bearing according to (1) or (2). With this configuration, the length of each recess can be made short and approximately the same, and the hardened sensor fixing member can be made uniform in the circumferential direction, allowing the sensor to be stably fixed to the sensor accommodating portion. Also, the thickness of the sensor accommodating portion can be made uniform, preventing sink marks during injection molding.

[0049] (6) The sensor accommodating portion and the nut holding portion protrude from the inboard end surface of the bottom plate portion to the inboard side independently of each other. A sensor-equipped hub unit bearing according to (1) or (2). With this configuration, the lengths of the recesses can be made short and approximately the same, and the hardened sensor fixing member can be made uniform in the circumferential direction, allowing the sensor to be stably fixed to the sensor accommodating portion. Also, the thickness of the sensor accommodating portion can be made uniform, preventing sink marks during injection molding. [Explanation of symbols]

[0050] 1. Hub unit bearing with sensor 2 Outer ring (outer component) 3 Hub (inner part) 4 Rolling elements 8a, 8b Outer raceway 9 Hub axle (inner part) 10 Inner ring (inner component) 12a, 12b Inner raceway 14 Magnetic Encoder 30 Cap with sensor holder (cap) 53 Bottom plate part 53a Inboard end face 54 Sensor housing 54a Inboard end face 55 Receiving hole 56, 56a Slit-shaped recess 57 Nut holder 57a Inboard end face 58 Neck 60 Insert nut (nut) 60a Inboard end face 70 Sensors 72 Sensor flange 80 Sealing member (sensor fixing member)

Claims

1. an outer member having a double row outer ring raceway on an inner circumferential surface; an inner member having a double row inner ring raceway on an outer circumferential surface thereof facing the double row outer ring raceway; A plurality of rolling elements are arranged to roll freely between the double row inner ring raceways and the double row outer ring raceways; a magnetic encoder fixed to an inboard end of the inner member; a cap with a sensor holder that is fitted and fixed to an inboard end of the outer member, closes an opening on the inboard side of the outer member, and holds a sensor that detects a displacement of the magnetic encoder; A sensor-equipped hub unit bearing comprising: the sensor holder cap is formed integrally with a sensor accommodating portion having an accommodating hole capable of accommodating the sensor such that the sensor faces the magnetic encoder, and a nut holding portion for holding a nut for fixing a sensor flange provided on the sensor, the sensor accommodating portion and the nut holding portion being protruded from a bottom plate portion of the sensor holder cap toward the inboard side, an inboard end face of the nut holding portion or an inboard end face of a nut fixed to the nut holding portion protrudes inboard further than the inboard end face of the sensor accommodating portion, an inboard end surface of the sensor accommodating portion has at least one recess extending radially from the accommodating hole; a sensor fixing member is provided between an inboard end surface of the sensor accommodating portion, the inboard end surface including the recess, and the sensor flange; Hub unit bearing with sensor.

2. The recess is located at a position other than on a line connecting the center of the sensor accommodating portion and the center of the nut holding portion. The sensor-equipped hub unit bearing according to claim 1.

3. the sensor fixing member is a sealing member that is inserted between the inboard end surface of the sensor accommodating portion, including the recess, and the sensor flange, and hardens into a rubber-like sealing member; The sensor-equipped hub unit bearing according to claim 1.

4. The receiving hole of the sensor receiving portion is formed to have a diameter larger than an outer circumferential surface of the sensor, The sealing member is disposed between the receiving hole and an outer circumferential surface of the sensor. The sensor-equipped hub unit bearing according to claim 3.

5. The sensor accommodating portion and the nut holding portion are integrally formed so as to be continuous with each other via a constricted portion. The sensor-equipped hub unit bearing according to claim 1 or 2.

6. The sensor accommodating portion and the nut holding portion protrude from the inboard end surface of the bottom plate portion to the inboard side independently of each other. The sensor-equipped hub unit bearing according to claim 1 or 2.

Images