JP2008025845A - Bearing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent deformation of an inner ring to eliminate influence of caulking upon bearing accuracy by increasing rigidity of the inner ring. <P>SOLUTION: In this bearing device, a diagonally contact rolling bearing 2 is mounted on an outer periphery of a shaft body 1 having a caulking cylindrical part 3a at a shaft end, and the caulking cylindrical part of the shaft body is radially bent outward and is caulked to an end face of an opposite counter bore side end part of the inner ring 21 of the rolling bearing to prevent the rolling bearing from coming off and apply a pre-load to the bearing. In the caulking part, a swollen part 21c which has an outside diameter larger than a rolling element pitch circular diameter and smaller than an inner diameter of a counter bore of an outer ring is formed on an opposite counter bore side shoulder part of the inner ring, the counter bore side of the swollen part is in non-contact with the rolling element, and a pulser ring is mounted on the swollen part. The pulser ring, which includes a cylindrical part fitted to the outside diameter surface of the swollen part and a magnetic pole formation surface radially extending outward from the opposite counter bore side end part of the cylindrical part is formed to have an L-shaped section, and the inside diameter of the magnetic pole formation surface is smaller than the outside diameter of the swollen part and larger than the outer peripheral edge of the caulking part. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a bearing device such as a vehicle hub unit attached to a vehicle such as an automobile.

  An example of the structure of a vehicle hub unit as a conventional bearing device of this type is shown in FIG.

  The illustrated vehicle hub unit B includes a hub wheel 1 and a double-row outward angular ball bearing 2. The hub wheel 1 has an annular plate portion 11 and a shaft portion 12. A wheel (not shown) is attached to the annular plate portion 11 (see Patent Document 1).

  The shaft end of the shaft portion 12 has a structure of a caulking portion 3 formed by rolling caulking. An angular ball bearing 2 is fixed to the outer periphery of the shaft portion 12.

  The angular ball bearing 2 has an inner ring 21, an outer ring 22, a plurality of balls 23, and two crown-shaped cages 24, and the required preload (compressive stress) is obtained by pressing the inner ring 21 from the caulking portion 3. It is given and is kept from coming off.

  Such retaining and preloading for the angular ball bearing 2 are performed in place of tightening the shaft end of the shaft portion 12 with a nut so far, in order to reduce the weight and reduce the number of parts. Yes.

  Here, the caulking cylindrical portion 3a indicated by the phantom line in the drawing is constituted by the shaft end of the shaft portion 12, and is bent radially outward by the rolling of the caulking tool 90 and is angular. The ball bearing 2 is caulked to the end face of the inner ring 21 to form a caulking portion 3.

In addition, as the aforementioned caulking form, a rolling caulking apparatus C as shown in FIG. 9 is used. That is, the caulking tool 90 is tilted by a required angle θ with respect to the caulking cylindrical portion 3a at the shaft end of the shaft portion 12 of the hub wheel, and the caulking tool 90 is rolled by rotating the rotating shaft 91. The caulking cylindrical portion 3a is plastically deformed outward in the radial direction, and this plastically deformed portion is pressed against the outer end surface of the inner ring 21 as the caulking portion 3.
JP-A-10-332723

  In the case of this hub unit B, since the caulking force is applied to the inner ring 21 during the caulking, not only does the race of the inner ring 21 deform distorted and its roundness tends to decrease, and the bearing accuracy decreases. In addition, a circumferential tensile stress is applied to the race of the inner ring 21, which adversely affects the fatigue life of the angular ball bearing 2.

  Therefore, the applicant of the present application has considered that the thickness of the entire inner ring is set to be thick so as to be hard to be deformed by caulking to increase its rigidity.

  In this way, when increasing the overall thickness of the inner ring, we examined the case where the inner diameter of the inner ring was reduced to increase the thickness, but the shaft diameter of the shaft portion was reduced and the strength of the shaft portion was reduced. It was determined that it was impossible to implement.

  Accordingly, an object of the present invention is to increase the rigidity of the inner ring and make it difficult to deform the inner ring so that caulking does not affect the bearing accuracy.

  Another object of the present invention is to make it difficult to deform the inner ring without increasing the strength of the shaft portion against caulking by increasing the rigidity of the inner ring.

  The bearing device according to the present invention is provided with an oblique contact type rolling bearing attached to an outer periphery of a shaft body having a caulking cylindrical portion at a shaft end, and bending the caulking cylindrical portion of the shaft body radially outward. A bearing device that forms a caulking portion by caulking the end face of the bearing inner ring on the counter-counter side, and that prevents the rolling bearing from being pulled out and applies a preload. A bulging portion is formed on the shoulder on the counter-bore side of the inner ring that is smaller than the moving body pitch circle diameter, and the outer diameter is larger than the rolling element pitch circle diameter and smaller than the inner diameter of the counter bore of the outer ring. The counterbore side is not in contact with the rolling element, and a pulsar ring is attached to the bulging portion, and the pulsar ring includes a cylindrical portion attached to an outer diameter surface of the bulging portion, and an anti-counter bore of the cylindrical portion. Side edge Is formed in L-shaped cross section consisting of only extending pole forming surface Luo radially inwardly, the inner diameter of the magnetic pole forming surface is greater than the outer peripheral edge of the smaller caulking portion than the outer diameter of the bulging portion.

  According to the present invention, the anti-counter bore side shoulder of the inner ring bulges radially outward with respect to the standard specification product, and the radial thickness of the anti-counter bore side end is increased. Since the volume of the bore end increases and the section modulus increases, the rigidity of the counter counter bore end increases.

  Then, when the caulking tool is rolled and the caulking cylindrical portion is bent and deformed radially outward and caulked against the end face of the inner ring on the counter-counter side, the caulking force is applied to the end of the inner ring on the counter-bore side. However, the counter-counter-bore side end portion is highly rigid so that it is not deformed by caulking. Therefore, the raceway side portion of the inner ring is not deformed by caulking, and therefore the roundness of the raceway is maintained and the bearing accuracy is maintained.

  Also, since the counter-bore side end is not deformed by caulking, the inner ring raceway is not subjected to circumferential tensile stress by caulking, and as a result, bearing fatigue is reduced by caulking and the life is shortened. There is nothing.

  Further, according to the present invention, since the thickness of the entire inner ring is not set thick, there is no need to reduce the inner diameter of the inner ring, and therefore there is no need to reduce the shaft diameter, and the shaft strength is maintained. Thus, the inner ring can be crimped without deforming it.

  Further, according to the present invention, since the outer diameter of the counter counter-bore side end is larger than the rolling element pitch circle diameter and smaller than the inner diameter of the outer counter bore, the anti-counter bore is not degraded without reducing the rolling performance of the rolling element. The rigidity of the side end can be improved.

  In the present invention, even if the centrifugal force accompanying the rotation of the inner ring acts on the pulsar ring, the pulsar ring does not change the facing distance from the electromagnetic sensor, so that a rotation detection device with high rotation detection accuracy can be obtained.

  In this case, even if the radial clearance between the counter-bore end of the inner ring and the counter-bore of the outer ring is reduced by the bulging portion, the pulsar ring is provided on the axial outer end surface of the bulging portion. It is preferable that a rotation detecting device with high rotation detection accuracy can be obtained while improving the rigidity of the counter-bore side end without deteriorating the rolling performance of the moving body and easily securing the installation space of the rotation detecting device. It becomes a structure.

  As described above, in the bearing device of the present invention, the radial thickness of the end portion on the counter-counter side is increased, so that the inner ring has increased rigidity on the end portion on the counter-counter side. Therefore, for example, when the caulking tool is rolled and the caulking cylindrical portion is bent and deformed radially outward and caulked against the end face of the inner ring on the counter-counter side, the caulking force is applied to the end of the inner ring on the counter-bore side. The counter-bore side end is not deformed by caulking because the rigidity is large, and therefore the inner ring raceway side portion is not deformed by caulking, and the roundness of the trajectory is maintained, Bearing accuracy is maintained.

  Also, since the counter-bore side end is not deformed by caulking, the inner ring raceway is not subjected to circumferential tensile stress by caulking, and as a result, bearing fatigue is reduced by caulking and the life is shortened. There is nothing.

  Further, according to the present invention, since the wall thickness of the entire inner ring is not set thick, it is not necessary to reduce the inner diameter of the inner ring, and therefore it is not necessary to reduce the shaft diameter of the shaft part. Caulking can be carried out without deforming the inner ring while being held.

  Hereinafter, details of the present invention will be described based on embodiments shown in the drawings.

(Embodiment 1)
1 to 3 relate to a vehicle hub unit which is an example of a bearing device according to Embodiment 1 of the present invention. FIG. 1 illustrates a longitudinal side surface of the hub unit in a state before caulking by a caulking cylindrical portion 3a. FIG. 2 is a longitudinal sectional side view of the hub unit in a state after caulking by the caulking cylindrical portion 3a, and FIG. 3 is an enlarged view of a main part of FIG.

  In the figure, A indicates the entire vehicle hub unit as a bearing device, 1 is a hub wheel as a shaft body, 2 is a double-row outward angular ball bearing as a rolling bearing, and 3a is a shaft of the hub wheel 1. It is the cylindrical part for caulking provided at the end. The caulking cylindrical portion 3a shown in FIG. 1 is bent radially outward to become the caulking portion 3 shown in FIG.

  The hub wheel 1 has an annular plate portion 11 and a shaft portion 12 on which a double-row outward angular ball bearing 2 as an example of an oblique contact type rolling bearing is mounted. Note that the present invention is not limited to the angular contact ball bearing 2 as an oblique contact type rolling bearing, and may be anything as long as it is an oblique contact type rolling bearing. For example, rolling bearings such as counter bore ball bearings, single row angular contact ball bearings, and double row tapered roller bearings are included.

  The angular ball bearing 2 includes an inner ring 21 having a single race that is externally fitted to a small-diameter outer peripheral surface of a shaft portion 12, a single outer ring 22 having two rows of raceway grooves, and rolling elements arranged in two rows. As a plurality of balls 23 and two crown-shaped cages 24, and the large-diameter outer peripheral surface of the shaft portion 12 of the hub wheel 1 is used as one inner ring. As the inner ring 21, the inner ring of a general single row angular contact ball bearing is used as it is. A radially outward flange 25 is provided on the outer periphery of the outer ring 22 and is attached to an axle case (not shown) through the flange 25 in a non-rotating manner.

  In FIG. 2, reference numeral 30 denotes a lid.

  In short, the above-described vehicle hub unit A has an angular ball bearing 2 attached to the outer periphery of a hub wheel 1 having a caulking cylindrical portion 3a at the shaft end, and the caulking cylindrical portion 3a is bent radially outward. The ball bearing 2 is caulked against the end face of the counter-bore side end portion 21a of the inner ring 21 to prevent the angular ball bearing 2 from coming off and to apply a preload.

  The configuration featured in the first embodiment is that the counter-bore side shoulder 21b of the inner ring 21 bulges out in a non-contact state with respect to the ball 23 radially outward with respect to the standard specification product. That is, the radial thickness of the counter counterbore side end portion 21a is enlarged by the protruding portion 21c.

  Further, in the configuration further characterized in the first embodiment, the outer diameter D0 of the counter-bore side end portion 21a whose radial thickness is increased as described above is preferably the pitch circle diameter ( PCD) is larger than D1 and smaller than the inner diameter D2 of the counter bore 22a of the outer ring 22.

  Here, the standard specification product is defined as the height of the shoulder portion of the inner ring being not less than the minimum height required for preventing the rolling element from climbing and not more than the pitch circle diameter of the rolling element.

  In the vehicle hub unit A having the above-described configuration, the counter-counter-bore side end portion 21a is enlarged in thickness in the radial direction by the bulging portion 22a, and its rigidity is increased.

  Therefore, when the caulking tool is rolled and the caulking cylindrical portion 3a of FIG. 1 is bent and deformed radially outward and caulked against the end face of the counter-bore side end portion 21a of the inner ring 21, the caulking force is applied to the inner ring 21. Even if it is applied to the counter-counter bore side end 21a, the counter-counter bore end 21a is not rigidly deformed by caulking because it has high rigidity as described above.

The outer diameter of the counter counter side end 21a is D0, and the pitch circle diameter P.sub. C. D. Is D1 and the inner diameter of the counter bore 22a of the outer ring 22 is D2, the above magnitude relationship is D1 ≦ D0 ≦ D2, but a more preferable range is 0.15 in increasing the rigidity of the counter-bore side end. ≦ (D0−D1) / (D2−D1) ≦ 0.75
It is.

  The material of the inner ring 21 is preferably a high carbon chromium bearing steel according to JIS standards, but the material is not limited to this.

  Therefore, the caulking does not affect the raceway side portion of the inner ring 21 and the raceway is not deformed by caulking, so that the roundness of the raceway is maintained and the bearing accuracy is maintained.

  Further, since the counter-counter bore side end portion 21a is not deformed by caulking, the caulking does not apply a circumferential tensile stress to the race of the inner ring 21, and as a result, the bearing fatigue is reduced by caulking and the service life is reduced. It will not be shortened.

  Further, since the inner ring 21 is not set to have a large thickness, the inner diameter of the inner ring 21 is not reduced, that is, the shaft diameter of the hub wheel 1 does not need to be reduced. The inner ring 21 can be crimped without being deformed.

  The above-described first embodiment is not limited to a vehicle hub unit that is a combination of the hub wheel 1 and the angular ball bearing 2, and the hub wheel or the like is used as a shaft and an oblique contact such as an angular ball bearing or the like. The present invention can also be applied to a bearing device in which a type of rolling bearing is disposed on the outer periphery of the shaft portion of the shaft body.

(Embodiment 2)
4 to 6 relate to a second embodiment of the present invention, FIG. 4 is a longitudinal side view of a bearing device according to the second embodiment, and FIG. 5 is a partially exploded perspective view of a rotation detection device provided in the bearing device of FIG. FIG. 6 is an enlarged view of a main part of the bearing device shown in FIG. FIG. 7 is an enlarged view of a main part of a conventional bearing device for comparison with the second embodiment.

  4 to 6, the same reference numerals are given to the portions corresponding to those in FIGS. 1 to 3, and description of the portions related to the same reference numerals is omitted.

  The configuration characterized in the second embodiment is that a rotation detection device 40 for detecting the rotation speed of the wheel is provided.

  In other words, the rotation detection device 40 included in the bearing device of the second embodiment is used when, for example, information input means in an automobile ABS (anti-lock brake system) or other data regarding the rotation state of the wheel is required.

  The rotation detection device 40 includes a pulsar ring 41, an electromagnetic sensor 42, and a control unit 43.

  The pulsar ring 41 is attached to the outer end surface in the axial direction of an annular bulging portion 21c provided at the counter-bore side end portion 21a of the inner ring 21 of the angular ball bearing 2 which is a rotating portion of the bearing device A.

  The electromagnetic sensor 42 is attached to the lid 30 which is a non-rotating part of the bearing device A.

  The control unit 43 is attached to the electromagnetic sensor 42 via wiring and includes a microcomputer or the like, and calculates the rotational speed of the wheel from the output signal of the electromagnetic sensor 42 and performs various controls.

  In the bearing device A of the second embodiment, a wheel (not shown) is attached to the outer surface of the annular plate portion 11 of the hub wheel 1, so that the rotational speed of the wheel corresponds to the rotational speed of the pulsar ring 41. Therefore, the magnetic change of the pulsar ring 41 corresponds to the rotational speed of the wheel.

  Specifically, as shown in FIG. 5, the pulsar ring 41 is configured by a ring body configured by alternately arranging N magnetic poles and S magnetic poles in the circumferential direction and including a magnetic pole forming surface, and the electromagnetic sensor 42 includes The sensor surface is disposed to face the magnetic pole forming surface of the pulsar ring 41 in the axial direction, and an electromagnetic signal having a frequency corresponding to the alternating proximity period of the N and S magnetic poles of the pulsar ring 41 is output to the control unit 43. Can be done.

  In the control unit 43, data such as the rotational speed of the wheel is calculated from the frequency of the electromagnetic signal.

  The rotation detection device 40 according to the second embodiment and the conventional rotation detection device 40a will be described with reference to FIGS. FIG. 6 shows a rotation detection device 40 according to the second embodiment, and FIG. 7 shows a conventional rotation detection device 40a.

  In the case of the rotation detecting device 40 according to the second embodiment, the essential part of which is shown in FIG. 6, the counter-bore side end 21a of the inner ring 21 of the angular ball bearing 2 is bulged in the radial direction by the bulging portion 21c. The axially outer end surface of the bulging portion 21c provides a wide installation space for the pulsar ring 41. Therefore, the pulsar ring 41 can be installed on the outer end surface in the axial direction of the bulging portion 21c, and the electromagnetic sensor 42 can be installed facing this in the axial direction.

  In the case of the rotation detection device 40 of the second embodiment having the above-described configuration, even if a centrifugal force accompanying the rotation of the inner ring 22 acts on the pulsar ring 41, the magnetic pole forming surface of the pulsar ring 41 is not displaced in the axial direction. The spacing between the sensor 42 and the sensor surface never changes. Therefore, the output of the electromagnetic sensor 42 for detecting the alternating proximity period of each magnetic pole from the pulsar ring 41 corresponds to the rotational speed of the wheel accurately, and the rotation detection accuracy can be made high.

  On the other hand, in the case of the conventional rotation detecting device 40a whose main part is shown in FIG. 7, since the bulging portion 21c is not provided, the pulsar ring 41 is extended in the axial direction, while the electromagnetic sensor is disposed on the axially outer end surface of the outer ring 22. 42, and the pulsar ring 41 and the electromagnetic sensor 42 are configured to face each other in the radial direction. Therefore, when the centrifugal force accompanying the rotation of the inner ring 22 acts on the pulsar ring 41, the pulsar ring 41 bends inward and outward in the radial direction as shown by the phantom line, and the distance between the electromagnetic sensor 42 and the electromagnetic sensor 42 is kept constant. It becomes difficult. Thus, if the facing distance between the pulsar ring 41 and the electromagnetic sensor 42 is changed, the rotation cannot be detected with high accuracy.

  In addition, although the rotation detection apparatus 40 of Embodiment 2 is comprised by the combination of the pulsar ring 41 and the electromagnetic sensor 42 in order to detect rotation of a wheel with a magnetic change, it is not limited to such a combination. .

  Further, the pulsar ring 41 of the above-described embodiment 2 has N and S magnetic poles alternately arranged in the circumferential direction on the magnetic pole forming surface, or a plurality of windows in the circumferential direction are formed at regular intervals or at regular rules. On the other hand, the electromagnetic sensor 42 is configured by a permanent magnet so as to generate and output a signal corresponding to an electromagnetic change in the circumferential direction accompanying the rotation of the pulsar ring 41. It is also possible to output a signal that changes the frequency of the electromagnetic sensing signal in accordance with the rotational speed of the motor, and to input the signal to the control unit 43 so that the control unit 43 detects the rotational speed from this signal.

Vertical side view of the vehicle hub unit according to the first embodiment of the present invention before caulking Vertical side view of the vehicle hub unit according to the first embodiment of the present invention after caulking The principal part enlarged view of Embodiment 1 shown by FIG. Vertical side view of a vehicle hub unit according to a second embodiment of the present invention The partial exploded perspective view of the rotation detection apparatus with which the hub unit for vehicles of Embodiment 2 is provided Main part enlarged view of Embodiment 2 Fig. 6 is an enlarged view of a main part corresponding to Fig. 6. Vertical side view of a conventional vehicle hub unit Process drawing for explaining the caulking form of the caulking portion of FIG.

Explanation of symbols

A Vehicle hub unit 1 Hub wheel (shaft body)
12 Shaft part of hub wheel 2 Double row outward angular contact ball bearing (rolling bearing)
3 Caulking portion 3a Caulking cylinder portion 21 Inner ring 21a Inner ring 21 counter-counter side end 21b Inner ring 21 counter-counter side shoulder 21c Anti-counter bore end 21a bulging portion 22 Outer ring 22a Outer ring 22 counter bore 23 balls (rolling elements)
40 Rotation detector 41 Pulsar ring 42 Electromagnetic sensor

Claims (1)

An oblique contact type rolling bearing is attached to the outer periphery of a shaft body having a caulking cylindrical portion at the shaft end, and the caulking cylindrical portion of the shaft body is bent radially outwardly to counter-bore the inner ring of the rolling bearing. A bearing device that forms a caulked portion by caulking to an end face of a side end portion, and performs retaining and preloading for a rolling bearing,
The caulking portion has an outer peripheral edge diameter smaller than the rolling element pitch circle diameter,
On the shoulder on the counter-bore side of the inner ring, a bulging portion is formed whose outer diameter is larger than the rolling element pitch circle diameter and smaller than the inner diameter of the counter-bore of the outer ring,
The counterbore side of the bulging part is not in contact with the rolling element, and a pulsar ring is attached to the bulging part,
The pulsar ring is formed in an L-shaped cross section including a cylindrical portion attached to the outer diameter surface of the bulging portion, and a magnetic pole forming surface extending only radially inward from the counter counterbore side end portion of the cylindrical portion,
An inner diameter of the magnetic pole forming surface is smaller than an outer diameter of the bulging portion and larger than an outer peripheral edge of the caulking portion.

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