JP2014009731A - Wheel bearing device - Google Patents

Abstract

The present invention provides a wheel bearing device that improves detection accuracy and sealing performance, reduces assembly man-hours, and reduces costs.
A cup-shaped inner cap 15 is press-fitted into an inner periphery of an end portion of an outer member 2, which is formed of a nonmagnetic austenitic stainless steel plate, and has a cylindrical fitting portion 15a and a radially inward portion thereof. The disk portion 15b extends and is opposed to the magnetic encoder 14 through a slight axial clearance. The rotation speed sensor 21 is abutted on or close to the disk portion 15b, and is connected to the magnetic encoder 14 via the inner cap 15. The outer cap 16 is formed of a steel plate, and is provided with a cylindrical fitting portion 16a and a bottom portion 16c extending radially inward from the outer cap 16 and closing the opening of the outer member 2. The inner cap 15 The inner cap 15 and the outer cap 16 are fitted and integrated with each other.
[Selection] Figure 1

Description

  The present invention relates to a wheel bearing device for rotatably supporting a wheel of an automobile or the like with respect to a suspension device, and more particularly to a wheel bearing device to which a rotation speed sensor for detecting the rotation speed of a wheel is attached.

  In general, a wheel bearing device in which a wheel of an automobile is rotatably supported with respect to a suspension device and an anti-lock brake system (ABS) is controlled to detect a rotation speed of the wheel is incorporated. Are known. Conventionally, in such a wheel bearing device, a sealing device is provided between an inner member and an outer member that are in rolling contact with a rolling element, and a magnetic encoder in which magnetic poles are alternately arranged in a circumferential direction is provided as the sealing device. In addition, the rotational speed detecting device is constituted by a magnetic encoder and a rotational speed sensor that is arranged facing the magnetic encoder and detects a magnetic pole change of the magnetic encoder accompanying the rotation of the wheel.

  In general, the rotational speed sensor is attached to the knuckle after the wheel bearing device is attached to the knuckle constituting the suspension device. However, in order to eliminate the complexity of adjusting the air gap between the rotational speed sensor and the magnetic encoder and to make it more compact, a wheel bearing device to which a rotational speed sensor is also attached has recently been proposed. .

  A structure as shown in FIG. 16 is known as an example of such a wheel bearing device. This wheel bearing device is supported and fixed to a knuckle (not shown), an outer member 51 serving as a fixing member having a double row outer raceway surface 51a formed on the inner periphery, and a double row ball on the outer member 51. A hub ring 53 inserted through 52 and an inner ring 54 fitted on the hub ring 53 are included.

  One inner rolling surface (not shown) is integrally formed on the outer periphery of the hub wheel 53, and the other inner rolling surface 54 a is formed on the outer periphery of the inner ring 54. The inner ring 54 is press-fitted into a shaft-shaped small diameter step portion 53 a extending in the axial direction from the inner rolling surface of the hub ring 53. The double-row balls 52 are respectively accommodated between these rolling surfaces and are held by a cage 55 so as to be freely rollable.

  The hub wheel 53 is integrally provided with a wheel mounting flange for mounting a wheel (not shown) on the outer periphery, and a crimped portion 56 is formed by plastically deforming an end portion of the small-diameter stepped portion 53a radially outward. The inner ring 54 is fixed in the axial direction by a fastening portion 56. A cover 57 is attached to the end of the outer member 51 to prevent leakage of lubricating grease sealed inside the bearing and intrusion of rainwater, dust, or the like into the bearing from the outside.

  The cover 57 is made of a nonmagnetic metal plate such as SUS304, an austenitic stainless steel plate, an aluminum alloy, or a synthetic resin plate, and includes a bottom plate portion 58 and an outer peripheral edge of the bottom plate portion 58. And a cylindrical portion 59 bent at a right angle inward in the axial direction. In addition, an outward flange-like butting portion 60 is provided in a state of being bent at a right angle outward from the axial inner end edge of the cylindrical portion 59, and is in contact with the end face of the outer member 51.

  The bottom plate portion 58 has a flat plate portion 58 a and a bulging portion 58 b, and the flat plate portion 58 a is provided near the outer peripheral edge of the bottom plate portion 58. Further, the bulging portion 58b is provided at a central portion of the bottom plate portion 58 and is provided at a portion that is radially inward from the flat plate portion 58a, and bulges inward in the axial direction from the flat plate portion 58a. Further, the outer peripheral surface of the inner end portion of the cylindrical portion 59 is covered with a sealing material 61 having elasticity such as an elastomer such as rubber over the entire circumference.

  Such a cover 57 is supported and fixed to the outer member 51 by fixing the cylindrical portion 59 to the inner end portion in the axial direction of the outer member 51 with an interference fit. The axially outer surface of the abutting portion 60 is abutted against the inner end surface of the outer member 51 over the entire circumference, and the axially outer surface of the flat plate portion 58a is pressed into the outer periphery of the inner ring 54. It faces the detection surface of the encoder 62 in close proximity via a minute gap.

  In addition, a sensor holding plate 64 for supporting the sensor 63 is fitted and fixed to the inner end of the outer member 51 in the axial direction by an interference fit. The sensor holding plate 64 is made of a ferrous metal such as carbon steel or stainless steel, a non-ferrous metal such as an aluminum alloy, or a synthetic resin, and is configured in a petri dish as a whole. The bottom plate portion 65 has a circular flat plate shape, and a fitting tube portion 66 bent at a right angle from the outer peripheral edge of the bottom plate portion 65 in the axially outward direction. A through hole 67 is formed in a portion near the outer diameter of the bottom plate portion 65, and a mounting hole 68 is formed in a portion closer to the center than the through hole 67, and a mounting hole 68 is formed on a part of the outer surface of the bottom plate portion 65. A nut 69 is fixed to a portion surrounding the outer periphery by welding, bonding, press-fitting, caulking, or the like.

  In such a sensor holding plate 64, the fitting cylinder portion 66 is fitted on the inner end portion in the axial direction of the outer member 51, and the cover 57 abuts between the bottom plate portion 65 and the end surface of the outer member 51. The part 60 is clamped from both sides in the axial direction. Accordingly, the cover 57 is prevented from being displaced inward in the axial direction, and the cover 57 is covered from the inner side in the axial direction through the space 70.

  The magnetic encoder 62 is press-fitted into the outer periphery of the inner ring 54. On the other hand, in order to fix the sensor 63 to the sensor holding plate 64, the tip portion of the magnetic encoder 62 is inserted into the space 70 through the through hole 67 formed in the sensor holding plate 64, and the flat plate portion constituting the bottom plate portion 58. While abutting against the axially inner side surface of 58a and the mounting flange 72 abutting against the axially inner side surface of the nut 69, an insertion hole formed with the mounting flange 72 and a mounting hole 68 formed in the sensor holding plate 64. The bolt 71 inserted through the insertion hole from the inside in the axial direction is screwed into the nut 69 and further tightened.

  In this way, the cover 57 that closes the opening of the internal space 73 in which the magnetic encoder 62 is installed can be prevented from being pushed into the magnetic encoder 62 side due to the pressing of the detection portion of the sensor 63 and the like. Axial displacement can be regulated with high accuracy. Further, it is possible to prevent the cover 57 from being deformed so as to reduce the detection accuracy of the sensor 63.

  Further, when the cylindrical portion 59 constituting the cover 57 is fitted into the end portion of the outer member 51, a force directed radially inward is applied to the bottom plate portion 58, but consumed to deform the bulging portion 58b. Is done. As a result, the deformation amount of the flat plate portion 58a can be sufficiently suppressed, and the axial position of the flat plate portion 58a can be regulated with high accuracy (see, for example, Patent Document 1).

JP 2010-180912 A

  In such a conventional wheel bearing device, among the cover 57 and the sensor holding plate 64 attached to the end of the outer member 51, the cover 57 attached to the inside is press-fitted into the inner peripheral surface of the end, The sensor holding plate 64 attached to the outside is press-fitted into the outer peripheral surface of the end portion. In this case, since the sensor holding plate 64 is an external fitting type, when the fitting member 66 is press-fitted into the outer member 51, the opening of the fitting cylinder portion 66 expands in a trumpet shape and the fixing force becomes weak, and the outer member 51 vibrates. There was a possibility that it would come out when a large load was applied and deformation occurred.

  In order to secure a predetermined air gap, it is necessary to position and fix the cover 57 and the sensor holding plate 64 to the outer member 51 with high accuracy. This increases assembly man-hours and becomes a factor that hinders cost reduction.

  The present invention has been made in view of such conventional problems, and provides a wheel bearing device that improves detection accuracy and sealing performance and reduces the number of assembly steps to reduce costs. Objective.

  In order to achieve such an object, the invention according to claim 1 of the present invention includes an outer member in which a double row outer rolling surface is integrally formed on the inner periphery, and a wheel for attaching a wheel to one end. A hub ring integrally having a mounting flange and formed with a small-diameter step portion extending in the axial direction on the outer periphery, and at least one inner ring press-fitted into the small-diameter step portion of the hub ring. An inner member in which a double row of inner rolling surfaces facing the outer rolling surface is formed, and a double row of rolling members housed between the outer member and the inner member so as to roll freely. A moving body, a pulsar ring that is externally fitted to the inner ring, and whose characteristics are alternately changed at equal intervals in the circumferential direction; and an opening on the outer side of the annular space formed in the outer member and the inner member. A seal for sealing and an end of the outer member on the inner side are fitted into the annular space. An inner cap having a sealing member for sealing the opening on the inner side, and a cup-shaped outer cap to which a rotational speed sensor is attached in a radially outer portion, and the rotational speed sensor is attached to the pulsar ring. In the wheel bearing device opposed to each other through the axial air gap, a cup-shaped inner cap is press-fitted into the inner periphery of the inner side end of the outer member through a predetermined shimiro, and the inner cap is nonmagnetic. A cylindrical fitting portion that is formed from an austenitic stainless steel plate and is press-fitted into the inner periphery of the inner side end of the outer member, and extends radially inward from the fitting portion, with a slight axial direction in the pulsar ring. There is a disk part facing each other through a gap, and the rotational speed sensor is abutted or brought close to the disk part, and is opposed to the pulsar ring via the inner cap. With the said outer cap is formed from a steel sheet, in a state polymerized to the inner cap, is press-fitted over a predetermined Interference in the peripheral edge portion of the outer member of the inner side of the inner cap. Here, the superposed state indicates that the inner cap and the outer cap are fitted together and integrated with each other, and are pressed into the inner periphery of the end of the outer member.

  In this way, the pulsar ring that is externally fitted to the inner ring and whose characteristics are alternately changed at equal intervals in the circumferential direction and the opening on the outer side of the annular space formed in the outer member and the inner member are sealed. A rotation speed sensor on the inner side end of the outer member, an inner cap provided with a sealing member for sealing the inner side opening of the annular space, and a radially outer portion. In a wheel bearing device having a cup-shaped outer cap to be mounted and a rotational speed sensor facing a pulsar ring via a predetermined axial air gap, a cup-shaped inner side on the inner periphery of the inner side end of the outer member A cylindrical fitting portion in which a cap is press-fitted through a predetermined shimoshiro, and this inner cap is formed of a nonmagnetic austenitic stainless steel plate and is press-fitted into the inner periphery of the inner side end of the outer member. The disk portion extends radially inward from the fitting portion and faces the pulsar ring through a slight axial clearance, and a rotational speed sensor is abutted or brought close to the disk portion, and the inner cap is The outer cap is formed from a steel plate and is superimposed on the inner cap, and is press-fitted through a predetermined shimoshiro to the inner periphery of the outer member on the inner side of the inner cap. Therefore, while improving detection accuracy and sealing performance, both caps can be press-fitted in a single press-fitting operation, and it is possible to provide a wheel bearing device that reduces assembly man-hours and reduces costs. .

  According to a second aspect of the present invention, the outer cap includes a cylindrical fitting portion that is press-fitted into the inner periphery of the inner side end of the outer member, and a radially inner portion from the fitting portion. A bottom portion that closes the opening on the inner side of the outer member, and a fitting insertion hole is formed at a horizontal position corresponding to the pulsar ring on the bottom portion, and the rotational speed sensor is mounted in the fitting insertion hole. Thus, the positioning accuracy of the rotational speed sensor can be improved by increasing the rigidity, and the rotational speed sensor and pulsar ring can be used even when the outer member and the inner member are relatively inclined due to a lateral load from the wheel. Fluctuations in the air gap can be suppressed, and stable detection accuracy can be obtained.

  According to a third aspect of the present invention, a step portion is formed at the opening end portion of the fitting portion of the outer cap, and the step portion and the fitting portion of the inner cap are set to a predetermined width dimension. If the opening end of the fitting portion of the inner cap is press-fitted until it abuts against the wall surface of the stepped portion, the air gap between the rotational speed sensor mounted in the fitting insertion hole of the outer cap and the pulsar ring is accurate. In addition to being able to set well, deformation at the time of press-fitting can be prevented even if the plate thickness of the inner cap is set small.

  According to a fourth aspect of the present invention, the fitting portion of the inner cap and the fitting portion of the outer cap are set to a predetermined width dimension, and the fitting of the inner cap to the fitting portion of the outer cap is performed. If the fitting part is fitted inside and the end surface of this fitting part is press-fitted until it abuts against the bottom part of the outer cap, the air gap between the rotation speed sensor and the pulsar ring that is fitted in the fitting hole of the outer cap In addition to being able to set with high accuracy, deformation at the time of press-fitting can be prevented even if the plate thickness of the inner cap is set small.

  According to a fifth aspect of the present invention, the fitting portion of the inner cap and the fitting portion of the outer cap are set to a predetermined width dimension, and the fitting of the outer cap is fitted into the fitting portion of the inner cap. If the fitting part is fitted inside and the end surface of this fitting part is press-fitted until it abuts against the disk part of the inner cap, the air between the rotational speed sensor and the pulsar ring that is fitted in the fitting hole of the outer cap The gap can be set with high accuracy, and deformation at the time of press-fitting can be prevented even if the plate thickness of the inner cap is set small.

  Further, as in the invention of claim 6, the outer cap includes a flange portion that overlaps and extends radially outward from the fitting portion, and is in close contact with an inner end face of the outer member, Press fitting until the fitting portion of the inner cap and the fitting portion of the outer cap are set to a predetermined width dimension, and the opening end of the fitting portion of the inner cap abuts the side surface of the flange portion of the outer cap In addition, if the side surface of the flange portion is press-fitted until it abuts against the end surface of the outer member, the air gap between the rotation speed sensor and the pulsar ring mounted in the insertion hole of the outer cap is accurately set. In addition, deformation at the time of press-fitting can be prevented even if the plate thickness of the inner cap is set small.

  Further, as in the invention described in claim 7, if the plate thickness of the inner cap is set to be thinner than the plate thickness of the outer cap, the air gap can be set small, and the detection accuracy is improved. While being able to raise, the sealing performance of a bearing space can be improved.

  Further, as in the eighth aspect of the invention, an inner fitting surface is formed on the inner periphery of the end portion of the outer member, and an outer fitting surface is formed on the inner side of the inner fitting surface via a step. The inner fitting surface and the outer fitting surface are simultaneously ground with the double-row outer rolling surface by a general-purpose grindstone, and the inner cap is press-fitted into the inner fitting surface. If the outer cap is press-fitted, the accuracy of roundness and roughness of each mating surface will be improved, and the mating will be stable and the mating area will be increased, so a stable mating force can be obtained and simultaneous grinding As a result, the number of processing steps can be reduced, and the cost can be reduced. In addition, it is possible to improve the assembly workability by minimizing the press-fitting stroke of the inner cap, and to prevent the inner cap from being deformed in the press-fitting process.

  In addition, as in the ninth aspect of the invention, an elastic member made of synthetic rubber is integrally joined to the joint portion between the fitting portion of the inner cap and the fitting portion of the outer cap by vulcanization adhesion. If the member is elastically deformed and pressure-bonded to the fitting surface of the outer member and is in close contact with the fitting portion of the inner cap, the airtightness of the fitting portion of the inner cap can be improved.

  The wheel bearing device according to the present invention integrally has an outer member integrally formed with a double row outer rolling surface on the inner periphery, and a wheel mounting flange for mounting the wheel on one end, and on the outer periphery. A hub wheel formed with a small-diameter step portion extending in the axial direction, and at least one inner ring press-fitted into the small-diameter step portion of the hub ring, and a double row of the double row facing the outer rolling surface of the double row on the outer periphery. An inner member in which an inner rolling surface is formed, a double-row rolling element housed in a freely rolling manner between the respective rolling surfaces of the outer member and the inner member, and an outer fit to the inner ring, Pulsar rings whose characteristics are alternately changed at equal intervals in the circumferential direction, a seal that seals the outer side opening of the annular space formed in the outer member and the inner member, and the outer member A sealing member that is fitted to the inner side end and seals the inner side opening. An inner cap and a cup-shaped outer cap to which a rotational speed sensor is mounted on a radially outer portion, and the rotational speed sensor is opposed to the pulsar ring via a predetermined axial air gap. In the bearing device, a cup-shaped inner cap is press-fitted through a predetermined scissors on the inner periphery of the inner side end of the outer member, the inner cap is formed of a nonmagnetic austenitic stainless steel plate, and the outer member A cylindrical fitting portion that is press-fitted into the inner periphery of the inner side end portion, and a disk portion that extends radially inward from the fitting portion and faces the pulsar ring via a slight axial clearance, The rotational speed sensor is abutted or brought close to the disc part, and is arranged to face the pulsar ring via the inner cap, and the outer cap is made of steel plate. In the state of being formed and superposed on the inner cap, the inner end of the inner cap is press-fitted into the inner periphery of the end of the outer member via a predetermined shimeiro, thereby improving detection accuracy and sealing performance. Both the caps can be press-fitted in a single press-fitting operation, and the wheel bearing device can be provided in which the number of assembling steps is reduced and the cost is reduced.

It is a longitudinal section showing a 1st embodiment of a bearing device for wheels concerning the present invention. It is a principal part enlarged view which shows the detection part of FIG. It is a perspective view which shows the state which unitized the inner cap and the outer cap of FIG. It is a principal part enlarged view which shows the drain part of FIG. It is explanatory drawing which shows the grinding method of the outer member of the wheel bearing apparatus which concerns on this invention. It is explanatory drawing which shows the assembly method of the wheel bearing apparatus which concerns on this invention. (A) is explanatory drawing which shows the assembly method of the pulsar ring of FIG. 6, (b) is explanatory drawing which shows the modification of (a). It is explanatory drawing which shows the assembly method of the inner side cap and outer side cap of FIG. (A) is explanatory drawing which shows the assembly method of the inner side cap and outer side cap of FIG. 11, (b) is explanatory drawing which shows the modification of (a). It is a longitudinal cross-sectional view which shows 2nd Embodiment of the wheel bearing apparatus which concerns on this invention. It is a principal part enlarged view which shows the detection part of FIG. It is a longitudinal cross-sectional view which shows 3rd Embodiment of the wheel bearing apparatus which concerns on this invention. It is a principal part enlarged view which shows the detection part of FIG. It is a longitudinal cross-sectional view which shows 4th Embodiment of the wheel bearing apparatus which concerns on this invention. It is a principal part enlarged view which shows the detection part of FIG. It is a principal part enlarged view which shows the conventional wheel bearing apparatus.

  An outer member integrally having a vehicle body mounting flange to be attached to the vehicle body on the outer periphery, a double row outer rolling surface formed integrally on the inner periphery, and a wheel mounting flange for mounting a wheel on one end A hub wheel integrally formed and having an inner rolling surface facing one of the outer rolling surfaces of the double row on the outer periphery, and a small-diameter step portion extending in the axial direction from the inner rolling surface, and the hub wheel An inner member formed of an inner ring press-fitted into a small-diameter step portion and formed with an inner rolling surface facing the other of the double row outer rolling surfaces, and the rolling of each of the outer member and the inner member. A double row rolling element housed between the surfaces so as to roll freely, a magnetic encoder externally fitted to the inner ring, and an outer side opening of the annular space formed in the outer member and the inner member are sealed. And a seal that fits on the inner side end of the outer member, An inner cap having a sealing member for sealing the opening on the inner side, and a cup-shaped outer cap to which a rotational speed sensor is mounted on the radially outer portion, the rotational speed sensor being attached to the magnetic encoder In a wheel bearing device that faces a predetermined axial air gap, a cup-shaped inner cap is press-fitted through a predetermined shimiro to the inner periphery of the inner side end of the outer member. A cylindrical fitting portion that is formed by press working from a magnetic austenitic stainless steel plate and is press-fitted into the inner periphery of the inner side end of the outer member, and extends radially inward from the fitting portion. The encoder is provided with a disk part facing the slight gap in the axial direction, and the rotational speed sensor is abutted or brought close to the disk part, A cylindrical fitting portion that is disposed opposite to the magnetic encoder, the outer cap is formed by pressing from a steel plate, and is press-fitted into the inner periphery of the inner side end of the outer member, and the fitting portion A bottom portion that extends inward in the radial direction and closes the opening on the inner side of the outer member and is overlapped with the inner cap, and is predetermined on the inner periphery of the end of the outer member on the inner side of the inner cap. It is press-fitted through a shimeshiro.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing a first embodiment of a wheel bearing device according to the present invention, FIG. 2 is an enlarged view of a main part showing a detection unit of FIG. 1, and FIG. 3 is an inner cap of FIG. 4 is a perspective view showing a state in which the outer cap is unitized, FIG. 4 is an enlarged view of a main part showing the drain part of FIG. 1, and FIG. 5 is an explanation showing a grinding method of the outer member of the wheel bearing device according to the present invention. FIGS. 6 and 6 are explanatory views showing a method of assembling the wheel bearing device according to the present invention, FIG. 7A is an explanatory view showing the method of assembling the pulsar ring of FIG. 6, and FIG. FIG. 8 is an explanatory view showing a method for assembling the inner cap and the outer cap in FIG. 6, and FIG. 9 (a) is a method for assembling the inner cap and the outer cap in FIG. Explanatory drawing shown, (b) is explanatory drawing which shows the modification of (a). In the following description, the side closer to the outer side of the vehicle when assembled to the vehicle is referred to as the outer side (left side in FIG. 1), and the side closer to the center is referred to as the inner side (right side in FIG. 1).

  This wheel bearing device is called the third generation on the driven wheel side, and is a double row rolling element (ball) accommodated between the inner member 1 and the outer member 2 and between the members 1 and 2 so as to roll freely. 3 and 3. The inner member 1 includes a hub ring 4 and an inner ring 5 press-fitted into the hub ring 4 through a predetermined shimiro.

  The hub wheel 4 integrally has a wheel mounting flange 6 for mounting a wheel (not shown) at an end portion on the outer side, and has one (outer side) inner rolling surface 4a on the outer periphery and the inner rolling surface. A small diameter step 4b extending in the axial direction from the surface 4a is formed. Hub bolts 6a are planted on the wheel mounting flange 6 at equal intervals in the circumferential direction.

  The inner ring 5 is formed with the other (inner side) inner raceway surface 5a on the outer periphery and is press-fitted into the small-diameter stepped portion 4b of the hub wheel 4 to form a back-to-back type double row angular contact ball bearing. The end portion of 4b is fixed in the axial direction in a normal state to which a predetermined bearing preload is applied by a caulking portion 4c formed by plastic deformation. Thereby, weight reduction and size reduction can be achieved. The inner ring 5 and the rolling elements 3 and 3 are made of high carbon chrome steel such as SUJ2, and are hardened in the range of 58 to 64 HRC up to the core part by quenching.

  The hub wheel 4 is made of medium and high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and includes an inner rolling surface 4a and an inner side of a wheel mounting flange 6 serving as a seal land portion of a seal 8 described later. The surface hardness is hardened to a range of 58 to 64 HRC by induction hardening from the base 6b to the small diameter step 4b. Note that the crimped portion 4c has a raw surface hardness after forging. Thereby, it has sufficient mechanical strength with respect to the rotational bending load applied to the wheel mounting flange 6, the fretting resistance of the small-diameter step portion 4b serving as the fitting portion of the inner ring 5 is improved, and the minute There is no occurrence of cracks and the like, and the plastic working of the caulking portion 4c can be performed smoothly.

  The outer member 2 integrally has a vehicle body mounting flange 2b to be attached to the knuckle 9 on the outer periphery, and a cylindrical pilot portion 2c fitted to the knuckle 9 is formed on the inner side of the vehicle body mounting flange 2b. The outer outer rolling surface 2a facing the inner rolling surface 4a of the hub wheel 4 and the inner outer rolling surface 2a facing the inner rolling surface 5a of the inner ring 5 are integrally formed on the inner periphery. ing. Double-row rolling elements 3 and 3 are accommodated between these rolling surfaces and are held by the cages 7 and 7 so as to be freely rollable. A seal 8 is attached to the opening on the outer side of the annular space formed between the outer member 2 and the inner member 1, and an inner cap 15 described later is attached to the opening on the inner side. This prevents the grease sealed inside the bearing from leaking to the outside and prevents rainwater and dust from entering the bearing from the outside.

  The outer member 2 is formed of medium and high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and at least the double row outer rolling surfaces 2a and 2a have a surface hardness of 58 to 64 HRC by induction hardening. Has been cured.

  The seal 8 is constituted by an integral seal composed of a cored bar 10 press-fitted into the inner periphery of the outer end of the outer member 2 and a seal member 11 integrally joined to the cored bar 10 by vulcanization adhesion. ing. The metal core 10 has a substantially L-shaped cross section by press working from an austenitic stainless steel plate (JIS standard SUS304 type or the like) or a cold rolled steel plate (JIS standard SPCC type or the like).

  On the other hand, the seal member 11 is made of a synthetic rubber such as NBR (acrylonitrile-butadiene rubber), and extends in a radially outward direction, and is in contact with a side lip 11a that slidably contacts the outer peripheral surface of the base portion 6b via a predetermined axial squeeze The dust lip 11b and a grease lip 11c extending inward in the radial direction and in sliding contact with the outer peripheral surface of the base portion 6b via a predetermined radial shimiro are provided. And the sealing member 11 wraps around and joins so that the outer surface of the metal core 10 may be covered, and what is called a half metal structure is comprised. Thereby, airtightness can be improved and the inside of a bearing can be protected.

  In addition to the exemplified NBR, the material of the seal member 11 includes, for example, HNBR (hydrogenated acrylonitrile butadiene rubber), EPDM (ethylene propylene rubber), etc. having excellent heat resistance, and heat resistance and chemical resistance. Examples thereof include ACM (polyacrylic rubber), FKM (fluororubber), and silicon rubber, which are excellent in the above.

  In addition, although the wheel bearing apparatus comprised by the double row angular contact ball bearing which used the ball for the rolling elements 3 and 3 was illustrated here, it is not restricted to this but is comprised by the double row tapered roller bearing using a tapered roller It may be what was done.

  In the present embodiment, the pulsar ring 12 is press-fitted into the outer periphery of the inner ring 5. As shown in an enlarged view in FIG. 2, the pulsar ring 12 includes a support ring 13 formed in an annular shape and a magnetic encoder 14 integrally joined to the side surface of the support ring 13 by vulcanization adhesion or the like. ing. This magnetic encoder 14 is a rotary encoder for detecting the rotational speed of a wheel by mixing magnetic powder such as ferrite in an elastomer such as rubber and magnetizing magnetic poles N and S alternately in the circumferential direction.

  The support ring 13 is formed into a substantially L-shaped cross section by pressing from a ferromagnetic steel plate, for example, a ferritic stainless steel plate (JIS standard SUS430 series or the like) or a rust-proof cold-rolled steel plate. And a standing plate portion 13b extending radially outward from the cylindrical portion 13a. The magnetic encoder 14 is joined to the inner side surface of the upright plate portion 13b.

  Here, the inner cap 15 is attached to the outer member 2 to close the opening on the inner side of the outer member 2. The inner cap 15 has corrosion resistance and is formed into a cup shape by pressing from a non-magnetic austenitic stainless steel plate so as not to adversely affect the sensing performance of the rotational speed sensor 21 described later. A cylindrical fitting portion 15a that is press-fitted into the inner periphery of the inner side end of the inner portion of the inner side of the fitting portion 15a extends radially inward from the end portion of the fitting portion 15a, and faces the magnetic encoder 14 through a slight axial clearance. A disc portion 15b and a bottom portion 15d for closing the opening on the inner side of the outer member 2 via a bent portion 15c bulging from the disc portion 15b to the outer side are provided.

  In this embodiment, an outer cap (outer cap) 16 is further press-fitted and fixed to the inner side of the inner cap 15. Specifically, an outer fitting surface 20 is formed on the opening side (inner side) of the inner fitting surface 19 of the outer member 2 via a predetermined step 19 a, and the outer cap 16 is connected to the outer fitting surface 20. It is press-fitted through a predetermined scissors. The inner cap 15 is integrated with the outer cap 16 in advance.

  The outer cap 16 is formed into a cup shape from a cold-rolled steel plate by pressing, and has a cylindrical fitting portion 16a that is press-fitted into the outer fitting surface 20 of the outer member 2, and a radially outer portion from the fitting portion 16a. And a bottom portion 16c extending from the flange portion 16b to be in close contact with the inner end face 2d of the outer member 2 and a bottom portion 16c for closing the opening portion on the inner side of the outer member 2 from the flange portion 16b. .

  A step portion 16aa is formed at the opening end portion of the fitting portion 16a of the outer cap 16, and the opening end portion 15aa of the fitting portion 15a of the inner cap 15 is fitted to the step portion 16aa. In this case, the fitting portion 15a and the step portion 16aa of the inner cap 15 are set to a predetermined width dimension, and the opening end portion 15aa of the fitting portion 15a of the inner cap 15 is press-fitted until it abuts against the wall surface of the step portion 16aa. Thus, the air gap between the rotation speed sensor 21 mounted in the insertion hole 17 of the outer cap 16 and the magnetic encoder 14 can be set with high accuracy, and the inner cap 15 has a thickness greater than the plate thickness t2 of the outer cap 16. Even when the plate thickness t1 is set small, deformation at the time of press-fitting can be prevented.

  And the elastic member 18 which consists of synthetic rubbers, such as NBR, is integrally joined to this joined part by vulcanization adhesion. The elastic member 18 includes an annular protrusion 18 a that protrudes radially outward from the outer diameter of the fitting portion 16 a of the outer cap 16, and is in close contact with the outer diameter of the fitting portion 15 a of the overlapped inner cap 15. Then, the outer fitting surface 20 of the outer member 2 is regulated to Ra1 μm or less by grinding finish, and the annular protrusion 18a is elastically deformed to the outer fitting surface 20 of the outer member 2 when the outer cap 16 is fitted. The inner cap 15 has a half metal structure to improve the airtightness of the fitting portion 15a.

  An insertion hole 17 is formed in a horizontal position corresponding to the magnetic encoder 14 in the bottom portion 16 c of the outer cap 16, and a rotation speed sensor 21 described later is inserted into the insertion insertion hole 17. Thus, since the outer cap 16 includes the flange portion 16b that is in close contact with the end surface 2d of the outer member 2, the rigidity can be increased and the positioning accuracy of the rotational speed sensor can be improved, and the insertion hole 17 can be provided. If it is formed in a horizontal position and the rotation speed sensor 21 is mounted in the fitting insertion hole 17, it can rotate even when the outer member 2 and the inner member 1 are relatively inclined due to a lateral load from the wheel. The fluctuation of the air gap between the speed sensor 21 and the magnetic encoder 14 can be suppressed, and stable detection accuracy can be obtained.

  Further, a fixing nut 23 is fixed to a perforation 22 formed on the center side of the outer cap 16 by a diameter-enlarging process at the end. The fixing nut 23 is caulked and fixed to the bearing inner side (outer side) of the bottom portion 16 c of the outer cap 16. In addition to this, the fixing nut 23 may be fixed by, for example, welding, adhesion, press-fitting, or the like. And the rotational speed sensor 21 inserted by the insertion hole 17 of the outer side cap 16 is being fixed by fastening the attachment bolt 25 to the fixing nut 23 via the attachment member 24 (refer FIG. 1). Thus, in this embodiment, since the fixing nut 23 is fixed to the bearing inner side of the bottom portion 16c of the outer cap 16, the fixing nut 23 is pulled into the inner surface of the bottom portion 16b by fastening the mounting bolt 25, Dropping off can be prevented only by simply tightening the fixing nut 23.

  The rotation speed sensor 21 is an IC incorporating a magnetic detection element such as a Hall element, a magnetoresistive element (MR element) or the like that changes characteristics according to the flow direction of magnetic flux and a waveform shaping circuit that adjusts the output waveform of the magnetic detection element. The anti-lock brake system of the motor vehicle which consists of these etc. and detects the rotational speed of a wheel and controls the rotation speed is comprised. The rotational speed sensor 21 is inserted until it abuts on or approaches the disc portion 15b of the inner cap 15. As a result, a desired air gap can be obtained, the complicated air gap adjustment can be omitted, and the assembly workability can be improved, and the elastic member 18 made of synthetic rubber is integrally joined to the joint portion with the outer cap 16. Therefore, it is possible to provide a wheel bearing device that can reliably seal the inside of the bearing while maintaining hermeticity and improve the sealing performance.

  Further, when the inner cap 15 and the outer cap 16 are press-fitted into a simple cylindrical fitting surface, not only the press-fitting stroke of the inner cap 15 is increased and the assembling workability is lowered, but the thin inner cap 15 is also inserted in the press-fitting process. There is a risk of deformation. In this embodiment, since the outer fitting surface 20 is formed on the inner side of the inner fitting surface 19 via the step 19a, the press-fit stroke of the inner cap 15 is minimized and the assembly workability is improved. The deformation of the inner cap 15 in the press-fitting process can be prevented, and the reliability of the product can be improved.

  The outer cap 16 is formed from a stainless steel or iron steel plate by press working, and the iron steel plate is subsequently formed with a rust preventive film on the entire surface by cationic electrodeposition coating. The cationic electrodeposition coating is an anionic electrodeposition coating in which the product side is energized with the product side as the negative electrode while the positive electrode is energized with the product side as the positive electrode. Also good. This anion-type electrodeposition coating has the characteristics that the coating color stability and baking temperature can be set low, but this type of outer cap 16 is a powerful coating with excellent rust prevention and adhesion. Cationic electrodeposition coating made of an epoxy resin system or the like that can form a film is preferred.

  In the present embodiment, zinc phosphate treatment is applied as a base treatment (pretreatment) for cationic electrodeposition coating. Since the surface of the steel material as a raw material is roughened by a chemical reaction by this zinc phosphate treatment, the bite of the paint is improved and the adhesion is improved. Further, a sealer treatment may be performed after the zinc phosphate treatment. This sealer is a kind of metal surface treatment agent, for example, a so-called chemical conversion treatment in which a chemical conversion film can be formed by performing immersion for a short time of about 30 seconds to 2 minutes, or spray treatment. Excellent film adhesion can be secured, and a protective film of the material can be formed, and a strong rust prevention function and conductivity can be exhibited. In other words, the zinc phosphate treatment is applied as a base treatment for the cationic electrodeposition coating, and the sealer treatment is performed thereon to smooth the fine surface of the zinc phosphate coating, thereby causing the air during paint electrodeposition. Can be prevented. If air is involved, surface defects such as craters (uneven surfaces such as irregularities) may occur in the coating film, which is not preferable.

  Thus, in this embodiment, a rust preventive film made of cationic electrodeposition coating is formed on the contact portion of the outer cap 16 with the outer member 2, and zinc phosphate treatment is used as a base treatment for the cationic electrodeposition coating. As the coating is applied, the adhesion of the paint is improved, and the rust preventive film is not easily peeled off when being pressed into the outer member 2, and the smooth surface can be maintained by filling in the minute irregularities of the fitting surface. At the same time, the fitting portion 16a of the outer cap 16 can be prevented from rusting over a long period of time, and the outer fitting surface 20 is in close contact with the outer fitting surface 20 to prevent rusting of the outer fitting surface 20. Can be prevented.

  A vulcanized adhesive is applied in advance to the outer cap 16 before the cationic electrodeposition coating. In this case, only the contact portion between the outer fitting surface 20 of the outer member 2 and the end surface 2d on the inner side is applied. Instead of coating, by applying a vulcanized adhesive to the entire surface of the outer cap 16, the solidified vulcanized adhesive becomes a resin film, and good airtightness can be obtained.

  The plate thickness t1 of the inner cap 15 is set to be thinner than the plate thickness t2 of the outer cap 16. Specifically, the plate thickness t2 of the inner cap 15 is set to 0.2 to 1.0 mm while the plate thickness t2 of the outer cap 16 is set to 1.0 to 1.5 mm. As a result, the air gap can be set small, and the detection accuracy can be increased. Further, the weight can be reduced, and the workability can be improved to reduce the cost. If the plate thickness t1 is less than 0.2 mm, it is difficult to accurately shape the shape of the inner cap 15, and if it exceeds 1.0 mm, the air gap becomes large and desired magnetic characteristics can be obtained. This cannot be done and the detection accuracy is reduced.

  In the present embodiment, as shown in FIG. 3, the drain 26 is formed on the radially outer side of the bottom portion 16 c of the outer cap 16. The drain 26 is formed in the bulging portion 27 on the side close to the road surface of the fitting portion 16a and the bottom portion 16c. The bulging portion 27 is formed to protrude from the bottom portion 16c to the inner side by a predetermined dimension L. As shown in an enlarged view in FIG. 4, the bulging portion 27 is effective when the knuckle 9 is not flush with the end surface 2 d of the outer member 2 but protrudes toward the inner side. That is, by forming the drain 26 through the bulging portion 27 of the outer cap 16 in the radial direction, even if foreign matter such as rainwater enters the outer cap 16 from the outside, it flows into the bulging portion 27 portion. The foreign matter can easily and effectively be discharged outside without being blocked by the knuckle 9.

  Next, a method for grinding the outer member 2 will be described with reference to FIG. In the turning process, the outer member 2 includes a double row outer rolling surfaces 2a and 2a, an inner fitting surface 19 into which an inner cap (not shown) is press-fitted to an inner end, and the inner fitting. An outer fitting surface 20 into which the outer cap 16 is press-fitted through a predetermined step 19a is formed on the inner side of the mating surface 19 with a predetermined grinding allowance. Then, after the heat treatment step by induction hardening, in the grinding step, the double-row outer rolling surfaces 2a and 2a, and the inner fitting surface 19 and the outer fitting surface 20 are simultaneously ground by the overall grindstone 29.

  In the grinding process, the centering shoe 30 is slidably contacted at two circumferential positions of the pilot portion 2c formed on the inner side end portion of the outer member 2, and the outer side end surface 2e of the outer member 2 is contacted. The backing plate 31 is rotated in an abutted state, and the general-purpose grindstone 29 is rotated in a certain direction to form a desired shape and size. Note that the general-purpose grindstone 29 is previously formed into a desired shape and size by a rotary dresser (not shown), and is positioned with the outer member 2 while being fixed to the quill 32 of the spindle.

  In the present embodiment, the inner fitting surface 19 and the outer fitting surface 20 are ground together with the double-row outer rolling surfaces 2a, 2a by the overall grindstone 29. Accuracy such as circularity and roughness is improved, and the fitting portion is stabilized and the fitting area is increased, so that a stable fitting force can be obtained and the airtightness of the fitting portion is increased. Further, the number of processing steps can be reduced by simultaneous grinding, and the cost can be reduced.

  Next, a method for assembling the wheel bearing device will be described with reference to FIGS. As shown in FIG. 6, the wheel bearing device is placed on a cradle (not shown) with the wheel bearing device in the vertical type, that is, with the shaft center being vertical and the hub wheel 4 being downward in the figure. The pulsar ring 12 is press-fitted into the outer diameter of the inner ring 5 from the inner opening side of the outer member 2, and the inner cap 15 and the outer cap 16 are inserted into the inner fitting surface 19 and the outer fitting surface of the outer member 2. Press fit into 20. In this case, the inner cap 15 and the outer cap 16 are previously united (integrated) by fitting the opening end portion 15aa of the fitting portion 15a of the inner cap 15 into the step portion 16aa of the fitting portion 16a of the outer cap 16 in advance. In this unitized state, it is press-fitted into the outer member 2. Hereinafter, the assembly method of the pulsar ring 12 and the unitized inner cap 15 and outer cap 16 will be described in detail with reference to FIGS.

  As shown in FIG. 7A, the assembly of the pulsar ring 12 to the bearing device is performed by placing the wheel bearing device vertically and placing it on the cradle 28, and positioning and fixing the guide jig 33 on the end face of the inner ring 5. To do. The guide jig 33 has a flat shaft shape on the outer periphery, an annular groove 33a for accommodating the caulking portion 4c is formed at one end, and a tapered surface for centering the pulsar ring 12 on the outer periphery of the other end. 33b is formed.

  The guide jig 33 is a pilot formed at the outer side end of the hub wheel 4 while using the outer side surface 6c of the wheel mounting flange 6 or the outer side end surface of the hub wheel 4 as a reference surface in the axial direction. The part 6d is used as a reference plane in the radial direction.

  Next, the pulsar ring 12 is placed on the tapered surface 33 b of the guide jig 33, and the pulsar ring 12 is press-fitted to a predetermined position by the press-fitting jig 34. The press-fitting jig 34 has a cup shape, and a press-fitting portion 34 a that presses the pulsar ring 12 is protruded at one end, and the other end is a flat pressing surface with reference to the end surface 2 d on the inner side of the outer member 2. 34b and a locking surface 34d that contacts the inner side end surface 2d of the outer member 2 are formed, and a press device is disposed on the pressing surface 34b to press-fit the pulsar ring 12 until the locking surface 34d contacts the end surface 2d. In this case, the inner periphery of the recess 34c of the press-fitting jig 34 is set to an inner diameter that is inserted into the outer diameter of the guide jig 33 through a slight guide clearance, and the depth of the recess 34c is set to the locking surface 34d. Is set so that a clearance is formed so that the height of the guide jig 33 does not come into contact with the end face 2d. In other words, the axial position of the pulsar ring 12 is positioned with reference to the end surface 2 d on the inner side of the outer member 2.

  Further, as shown in FIG. 7B, the locking surface 34d 'of the press-fitting jig 34' is brought into contact with the side surface 2f on the inner side of the vehicle body mounting flange 2b of the outer member 2 so that the pulsar ring 12 is positioned in the axial direction. May be regulated.

  Next, assembling the inner cap and the outer cap into the bearing device, as shown in FIG. 8, in the case of the outer cap 16 with the flange portion 16b (in the case of the first embodiment of the present invention), the outer member. The unit of the inner cap 15 and the outer cap 16 unitized into the two inner fitting surfaces 19 and the outer fitting surfaces 20 is press-fitted. In this case, the outer cap 16 is pressed by the press-fitting jig 35, but a concave portion 35 a for guiding the outer periphery of the outer cap 16 is formed at one end of the press-fitting jig 35, and the locking surface 35 d at the end is formed. Positioning is completed by pressing the flange portion 16b until it abuts against the flange portion 16b of the outer cap 16 and its side surface abuts against the inner end surface 2d of the outer member 2. In the case of the outer cap 42 with the flange portion 16b (in the case of the fourth embodiment of the present invention), the inner cap unitized on the inner fitting surface 19 and the outer fitting surface 20 of the outer member 2 is used. After the units 38 and the outer cap 42 are press-fitted, positioning is completed by the same assembly as described above.

  On the other hand, as shown in FIG. 9A, in the case of the outer cap 37 without the flange portion 16b (in the case of the second embodiment of the present invention), the press-fitting jig 35 'has a cup shape and has an outer end at one end. A recess 35 a ′ that guides the outer periphery of the cap 37 and presses the outer cap 37 is formed, and the depth of the recess 35 a ′ is set for the axial positioning of the outer cap 37. It is pressed and positioned so as to contact the end surface 2d on the inner side, or, as shown in FIG. 9B, the locking surface 35d "of the press-fitting jig 35" is the side surface on the inner side of the vehicle body mounting flange 2b. Positioning is completed by pressing so as to abut against 2f. Since the axial position of the pulsar ring 12 and the axial position of the outer cap 37 are press-fitted on the same reference plane, the variation in distance between the magnetic encoder 14 of the pulsar ring 12 and the bottom 16c, which is the mounting surface of the rotational speed sensor 21 of the outer cap 37, varies. The variation in the air cap between the rotation speed sensor 21 and the magnetic encoder 14 can be reduced. Further, in the case of the outer cap 39 without the flange portion 16b (in the case of the third embodiment of the present invention), the same positioning as described above is possible.

  As described above, in the first to fourth embodiments, when the inner caps 15, 36, and 38 and the outer caps 16, 37, 39, and 42 are press-fitted, they are previously unitized, and in this state, the outer member 2 is attached to the outer member 2. Since the press-fitting method is adopted, both caps can be press-fitted in one press-fitting operation, the number of assembling steps can be reduced by half, and the cost can be reduced, and the flanges 16b of the outer caps 16, 42 can be achieved. Can be brought into contact with the end face 2d of the outer member 2, or the press fitting jig 35 can be brought into contact with the end face 2d of the outer member 2 or the side face 2f on the inner side of the vehicle body mounting flange 2b. It is not necessary and can be positioned and fixed accurately and easily.

  FIG. 10 is a longitudinal sectional view showing a second embodiment of the wheel bearing device according to the present invention, and FIG. 11 is an enlarged view of a main part showing the detection unit of FIG. Note that this embodiment basically differs from the above-described embodiment (FIG. 1) only in the configuration of both caps, and the same reference numerals are given to the same parts or parts having the same functions or parts having the same functions. Detailed description is omitted.

  This wheel bearing device is called the third generation on the driven wheel side, and is a double row rolling element 3, 3 accommodated between the inner member 1, the outer member 2, and both members 1, 2 so as to roll freely. And. In the present embodiment, the pulsar ring 12 is press-fitted into the outer periphery of the inner ring 5, and the inner cap 36 and the outer cap 37 are attached to the outer member 2 to close the opening on the inner side of the outer member 2.

  The inner cap 36 is formed into a cup shape by press working from a non-magnetic austenitic stainless steel plate having corrosion resistance, and is press-fitted into the inner fitting surface 19 of the outer member 2 as shown in an enlarged view in FIG. A cylindrical fitting portion 36a, a disc portion 15b extending radially inward from one end portion of the fitting portion 36a and facing the magnetic encoder 14 through a slight axial clearance, and the disc portion A bottom portion 15d that closes the opening on the inner side of the outer member 2 via a bent portion 15c that bulges from the outer side to the outer side is provided.

  On the other hand, the outer cap 37 is formed into a cup shape from a stainless steel or iron steel plate by pressing, and the outer fitting surface 20 of the outer member 2 is subsequently subjected to rust prevention treatment. And a bottom portion 16c extending radially inward from one end of the fitting portion 37a and closing the opening on the inner side of the outer member 2. The front end portion of the fitting portion 37a includes an elastic member 18 that is bonded or vulcanized, and includes an annular protrusion 18a that protrudes radially outward from the outer diameter of the fitting portion 16a of the outer cap 37. Is in close contact with the fitting portion 36 a of the inner cap 36.

  In the present embodiment, the fitting portion 36a of the inner cap 36 is previously fitted into the fitting portion 37a of the outer cap 37 to form a unit. In this case, the fitting portion 36a of the inner cap 36 and the fitting portion 37a of the outer cap 37 are set to a predetermined width dimension, and the opening end portion of the fitting portion 36a of the inner cap 36 is opposed to the bottom portion 16c of the outer cap 37. By press-fitting until they match, the air gap between the rotation speed sensor 21 and the magnetic encoder 14 mounted in the insertion hole 17 of the outer cap 37 can be accurately set.

  In the present embodiment, the fitting portion 36 a of the inner cap 36 is previously fitted into the fitting portion 37 a of the outer cap 37 to form a unit, and the fitting portion 37 a of the outer cap 37 is the outer fitting surface of the outer member 2. Therefore, even when the plate thickness t1 of the inner cap 36 is set smaller than the plate thickness t2 of the outer cap 37, deformation during press-fitting can be prevented.

  FIG. 12 is a longitudinal sectional view showing a third embodiment of the wheel bearing device according to the present invention, and FIG. 13 is an enlarged view of a main part showing the detection unit of FIG. Note that this embodiment basically differs from the above-described embodiment (FIG. 10) only in the configuration of both caps, and the same reference numerals are given to other parts and parts having the same function or the same function. Detailed description is omitted.

  This wheel bearing device is called the third generation on the driven wheel side, and is a double row rolling element 3, 3 accommodated between the inner member 1, the outer member 2, and both members 1, 2 so as to roll freely. And. In the present embodiment, the pulsar ring 12 is press-fitted into the outer periphery of the inner ring 5, and the inner cap 38 and the outer cap 39 are attached to the outer member 2 to close the inner-side opening of the outer member 2.

  The inner cap 38 is formed into a cup shape by pressing from a non-magnetic austenitic stainless steel plate having corrosion resistance, and is press-fitted into the fitting surface 40 of the outer member 2 as shown in an enlarged view in FIG. A cylindrical fitting portion 38a, a disc portion 15b extending radially inward from one end portion of the fitting portion 38a and facing the magnetic encoder 14 through a slight axial clearance, and the disc portion 15b A bottom portion 15d for closing the opening on the inner side of the outer member 2 through a bent portion 15c bulging from the outer side to the outer side.

  On the other hand, the outer cap 39 is formed into a cup shape from a stainless steel or iron steel plate by press working (the iron steel plate is subsequently subjected to rust prevention treatment) and press-fitted into the fitting portion 38a of the inner cap 38. And a bottom portion 16c that extends radially inward from one end portion of the fitting portion 39a and closes the opening on the inner side of the outer member 2.

  In the present embodiment, the fitting portion 39a of the outer cap 39 is previously fitted into the fitting portion 38a of the inner cap 38 to form a unit. In this case, the fitting portion 38a of the inner cap 38 and the fitting portion 39a of the outer cap 39 are set to a predetermined width dimension, and the opening end of the fitting portion 39a of the outer cap 39 is used as the disk portion 15b of the inner cap 38. The air gap between the rotational speed sensor 21 mounted in the insertion hole 17 of the outer cap 39 and the magnetic encoder 14 can be set with high accuracy and the plate thickness of the inner cap 38 can be set. Even when t1 is set smaller than the plate thickness t2 of the outer cap 39, deformation at the time of press-fitting can be prevented.

  An elastic member 41 made of synthetic rubber such as NBR is integrally joined to a joint portion of the fitting portion 38a of the inner cap 38 and the fitting portion 39a of the outer cap 39 by vulcanization adhesion. The elastic member 41 protrudes radially outward from the outer diameter of the fitting portion 38a of the inner cap 38, and is elastically deformed and crimped to the fitting surface 40 of the outer member 2 when the inner cap 38 is fitted. A metal structure is used to improve the sealing performance of the fitting portion 38a of the inner cap 38.

  In the present embodiment, the fitting portion 39a of the outer cap 39 is previously fitted into the fitting portion 38a of the inner cap 38 to form a unit, and the fitting portion 38a of the inner cap 38 is fitted to the fitting surface 40 of the outer member 2. Since the fitting width of both caps 38, 39 can be increased, the cap rigidity can be increased even if the plate thickness t1 of the inner cap 38 is set smaller than the plate thickness t2 of the outer cap 39, Deformation during press-fitting can be prevented.

  FIG. 14 is a longitudinal sectional view showing a fourth embodiment of the wheel bearing device according to the present invention, and FIG. 15 is an enlarged view of a main part showing the detection unit of FIG. Note that this embodiment is basically different from the above-described embodiment (FIG. 12) only in the configuration of the outer cap, and the same reference numerals are given to the same parts or parts having the same function or the same parts. Detailed description is omitted.

  This wheel bearing device is called the third generation on the driven wheel side, and is a double row rolling element 3, 3 accommodated between the inner member 1, the outer member 2, and both members 1, 2 so as to roll freely. And. In the present embodiment, the pulsar ring 12 is press-fitted into the outer periphery of the inner ring 5, and the inner cap 38 and the outer cap 42 are attached to the outer member 2 to close the inner side opening of the outer member 2.

  As shown in an enlarged view in FIG. 15, the inner cap 38 includes a fitting cylindrical fitting portion 38a that is press-fitted into the fitting surface 40 of the outer member 2, and the outer cap 42 is provided in the fitting portion 38a. The fitting part 42a is internally fitted.

  The outer cap 42 is formed into a cup shape from a stainless steel or iron steel plate by press working (the iron steel plate is subsequently subjected to rust prevention treatment), and a cylindrical fitting portion 42a. A flange portion 16b that overlaps and extends radially outward from one end portion of the joint portion 42a and is in close contact with the inner end surface 2d of the outer member 2, a flange portion 16b, and a radially inward portion from the flange portion 16b And a bottom portion 16 c that closes the opening on the inner side of the outer member 2.

  In the present embodiment, the fitting portion 42a of the outer cap 42 is previously fitted into the fitting portion 38a of the inner cap 38 to form a unit. In this case, the fitting portion 38a of the inner cap 38 and the fitting portion 42a of the outer cap 42 are set to a predetermined width dimension, and the opening end portion of the fitting portion 38a of the inner cap 38 is connected to the flange portion 16b of the outer cap 42. The rotational speed sensor 21 mounted in the insertion hole 17 of the outer cap 42 is press-fitted until it abuts against the side surface, and the side surface of the flange 16b is abutted until it abuts against the end surface 2d of the outer member 2. The air gap with the magnetic encoder 14 can be set with high accuracy.

  Further, an elastic member 43 made of synthetic rubber such as NBR is integrally joined to a joint portion of the fitting portion 38a of the inner cap 38 and the fitting portion 42a of the outer cap 42 by vulcanization adhesion. The elastic member 43 protrudes radially outward from the outer diameter of the fitting portion 42a of the outer cap 42, and is elastically deformed and crimped to the fitting portion 38a of the inner cap 38 when fitted to the inner cap 38. The tightness of the fitting part is improved. Further, an elastic member 44 made of synthetic rubber such as NBR is integrally joined to a contact portion between the flange portion 16b of the outer cap 42 and the outer member 2 by vulcanization adhesion. Thereby, the sealing performance of the inner cap 38 can be improved and the inside of the bearing can be protected.

  In the present embodiment, the fitting portion 42 a of the outer cap 42 is previously fitted into the fitting portion 38 a of the inner cap 38 to form a unit, and the fitting portion 38 a of the inner cap 38 is fitted to the fitting surface 40 of the outer member 2. Therefore, even when the plate thickness t1 of the inner cap 38 is set to be smaller than the plate thickness t2 of the outer cap 42, the cap rigidity can be increased and deformation during press-fitting can be prevented.

  The embodiment of the present invention has been described above, but the present invention is not limited to such an embodiment, and is merely an example, and various modifications can be made without departing from the scope of the present invention. Of course, the scope of the present invention is indicated by the description of the scope of claims, and further, the equivalent meanings described in the scope of claims and all modifications within the scope of the scope of the present invention are included. Including.

  The wheel bearing device according to the present invention can be applied to an inner ring rotating type wheel bearing device of any structure such as a driven wheel and a rolling element of a ball, a tapered roller or the like.

DESCRIPTION OF SYMBOLS 1 Inner member 2 Outer member 2a Outer rolling surface 2b Car body mounting flange 2c Pilot part 2d Outer member inner side end surface 2e Outer member outer side end surface 2f Car body mounting flange inner side side surface 3 Rolling element 4 Hub wheel 4a, 5a Inner rolling surface 4b Small diameter step 4c Caulking part 5 Inner ring 6 Wheel mounting flange 6a Hub bolt 6b Wheel mounting flange inner side base 6c Wheel mounting flange outer side surface 6d Hub wheel pilot section 7 Cage 8 Seal 9 Knuckle 10 Core 11 Seal member 11a Side lip 11b Dustrip 11c Grease lip 12 Pulsar ring 13 Support ring 13a Cylindrical portion 13b Standing plate portion 14 Magnetic encoder 15, 36, 38 Inner caps 15a, 16a, 36a, 37a, 38a, 39a, 42a Fitting part 15b Disk part 15c Curved portion 15d Bottom portion 15aa Open end portion 16aa of fitting portion of inner cap Step portion 16, 37, 39, 42 of fitting portion of outer cap Outer cap 16b Hook portion 16c Bottom portion 17 Insertion holes 18, 41, 43, 44 Elastic member 18a Annular projection 19 Inner fitting surface 19a Step 20 Outer fitting surface 21 Rotational speed sensor 22 Perforation 23 Fixing nut 24 Mounting member 25 Mounting bolt 26 Drain 27 Swelling portion 28 Receiving base 29 Total grindstone 30 Shoe 31 Backing plate 32 Quill 33 Guide jig 33a Annular groove 33b Tapered surface 34, 34 ', 35, 35', 35 "Press-fit jig 34a Press-fit portion 34b, 35b Press surface 34c, 35a, 35a 'Recess 34d, 34d', 35d, 35d ', 35d "Locking surface 40 Fitting surface 51 Outer member 51a Outer rolling surface 52 Ball 53 Hub wheel 53a Small diameter step 4 Inner ring 54a Inner rolling surface 55 Cage 56 Caulking portion 57 Cover 58 Bottom plate portion 58a Flat plate portion 58b Swelling portion 59 Cylindrical portion 60 Abutting portion 61 Sealing material 62 Magnetic encoder 63 Sensor 64 Sensor holding plate 65 Bottom plate portion 66 Fitting Joint tube portion 67 Through hole 68 Mounting hole 69 Nut 70 Space 71 Bolt 72 Mounting flange 73 Internal space L Amount of protrusion from the bottom of the bulging portion t1 Thickness of inner cap t2 Thickness of outer cap

Claims (9)

An outer member in which a double row outer rolling surface is integrally formed on the inner periphery;
A hub wheel integrally having a wheel mounting flange for mounting a wheel at one end, and having a small-diameter step portion extending in the axial direction on the outer periphery, and at least one inner ring press-fitted into the small-diameter step portion of the hub ring; An inner member in which a double row inner rolling surface facing the outer rolling surface of the double row is formed on the outer periphery,
A double row rolling element accommodated in a freely rolling manner between the rolling surfaces of the outer member and the inner member;
Pulsar ring that is externally fitted to the inner ring, and the characteristics are changed alternately and at equal intervals in the circumferential direction;
A seal that seals the opening on the outer side of the annular space formed in the outer member and the inner member;
An inner cap that is fitted to the inner side end of the outer member and includes a sealing member for sealing the inner side opening of the annular space, and a rotational speed sensor is attached to the radially outer portion. A cup-shaped outer cap
In the wheel bearing device in which the rotational speed sensor is opposed to the pulsar ring via a predetermined axial air gap,
A cup-shaped inner cap is press-fitted into the inner periphery of the inner side end of the outer member via a predetermined shimeiro, and the inner cap is formed of a nonmagnetic austenitic stainless steel plate. A cylindrical fitting portion that is press-fitted into the inner periphery of the end portion, and a disk portion that extends radially inward from the fitting portion and faces the pulsar ring via a slight axial clearance. The rotational speed sensor is abutted or approached, and is disposed opposite the pulsar ring via the inner cap,
A wheel characterized in that the outer cap is formed of a steel plate and is press-fitted into the inner periphery of the end of the outer member on the inner side of the inner cap via a predetermined shimiro while being superposed on the inner cap. Bearing device.   A cylindrical fitting portion in which the outer cap is press-fitted into the inner periphery of the inner side end of the outer member, and an inner opening of the outer member that extends radially inward from the fitting portion. 2. The wheel bearing device according to claim 1, further comprising: a bottom portion that closes the shaft, wherein a fitting insertion hole is formed at a horizontal position corresponding to the pulsar ring of the bottom portion, and the rotation speed sensor is mounted in the fitting insertion hole.   A step portion is formed at an opening end portion of the fitting portion of the outer cap, the step portion and the fitting portion of the inner cap are set to a predetermined width dimension, and the opening end portion of the fitting portion of the inner cap is formed. The wheel bearing device according to claim 2, wherein the wheel bearing device is press-fitted until abutting against a wall surface of the stepped portion.   The fitting portion of the inner cap and the fitting portion of the outer cap are set to a predetermined width dimension, and the fitting portion of the inner cap is fitted into the fitting portion of the outer cap, and the end surface of the fitting portion The wheel bearing device according to claim 2, wherein the wheel is press-fitted until it hits the bottom of the outer cap.   The fitting portion of the inner cap and the fitting portion of the outer cap are set to a predetermined width dimension, and the fitting portion of the outer cap is fitted into the fitting portion of the inner cap, and the end surface of the fitting portion The wheel bearing device according to claim 2, wherein the wheel is press-fitted until it hits the disc portion of the inner cap.   The outer cap includes a flange portion that overlaps and extends radially outward from the fitting portion and is in close contact with the inner end surface of the outer member, and the fitting portion of the inner cap and the fitting of the outer cap The joint portion is set to a predetermined width dimension, and is press-fitted until the opening end portion of the fitting portion of the inner cap abuts the side surface of the flange portion of the outer cap, and the side surface of the flange portion is the outer side. The wheel bearing device according to claim 2, wherein the wheel bearing device is press-fitted until it abuts against an end face of the member.   The wheel bearing device according to any one of claims 1 to 6, wherein a plate thickness of the inner cap is set to be thinner than a plate thickness of the outer cap.   An inner fitting surface is formed on the inner periphery of the end of the outer member, and an outer fitting surface is formed on the inner side of the inner fitting surface via a step, and the inner fitting surface and the outer fitting surface are combined. 2. The grinding wheel and the double row outer rolling surface are simultaneously ground by a mold grindstone, the inner cap is press-fitted into the inner fitting surface, and the outer cap is press-fitted into the outer fitting surface. Wheel bearing device.   An elastic member made of synthetic rubber is integrally joined to a joint portion between the fitting portion of the inner cap and the fitting portion of the outer cap by vulcanization adhesion, and this elastic member is elastically deformed to the fitting surface of the outer member. The wheel bearing device according to claim 1, wherein the wheel bearing device is in close contact with the fitting portion of the inner cap.

Images