JP4019537B2 - Rolling bearing with rotational speed detector - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rolling bearing with a rotational speed detection device that detects the rotational speed of a rotating member. This rolling bearing with a rotational speed detection device is used as information input means in an antilock brake system (ABS) of an automobile, for example.
[0002]
[Prior art]
Generally, in the ABS, a rotational speed detection device is attached to a hub unit of a vehicle in order to detect the rotational speed of a wheel.
[0003]
There are two types of rotational speed detection devices, so-called passive type and active type, depending on the detection form, both of which are configured by combining a pulsar ring and a sensor.
[0004]
In any of these types, pulsar rings and sensors are attached to the inner and outer rings of the bearing device provided in the hub unit. For example, when the above-described bearing device is used for inner ring rotation, the pulsar ring is attached to the inner ring side, and the sensor is attached to the outer ring side.
[0005]
By the way, conventionally, in consideration of detachability for maintenance, a palsar ring and a sensor are not directly attached to the inner and outer rings, but are indirectly attached using a support ring.
[0006]
[Problems to be solved by the invention]
In the above conventional example, since both the pulsar ring and the sensor are attached using the support ring, if either one of the two support rings is deformed at the time of attachment, the facing gap between the two becomes out of order. Therefore, there is a concern that the detection accuracy of the sensor varies.
[0007]
Moreover, since the pulsar ring is not an active component, it can be used semipermanently, but since the sensor is an active component, it can be said that there is a possibility of failure. From this, it can be said that it is not necessary to consider detachability for the pulsar ring, and use of the support ring is useless and is a cause of high cost.
[0008]
In addition, since the facing gap between the pulsar ring and the sensor is exposed to the outside, there is a risk that external foreign matter may enter the facing gap with the progress of use. It can also be done.
[0009]
In view of such circumstances, it is an object of the present invention to stabilize the detection accuracy of a sensor in a rolling bearing with a rotational speed detection device while minimizing structural waste as much as possible.
[0010]
[Means for Solving the Problems]
A rolling bearing with a rotational speed detection device according to claim 1 of the present invention includes a hub wheel including an annular plate portion to which a wheel is attached and a shaft portion, and an inner ring as a rotation-side member fitted on the outer periphery of the shaft portion. An outer ring as a non-rotating side member arranged concentrically with the hub wheel and the inner ring, a pulsar ring attached to the inner ring, and a sensor attached to the outer ring to detect rotation of the pulsar ring, A rotational speed detecting device for detecting a rotational speed of the inner ring with respect to the inner ring, and the inner ring is integrally formed with an axially outer end portion extending outwardly in the axial direction from the axially outer end portion of the outer ring. The pulsar ring is attached to an outer peripheral surface of the extension portion, and an annular support ring extending outward in the axial direction is attached to an axially outer end portion of the outer ring. To press A first cylindrical portion that is press-fitted into the inner peripheral surface of the shaft end of the outer ring, and a first cylinder that rises radially outward from the first cylindrical portion and contacts the end surface of the outer ring. An annular plate portion, a second cylindrical portion connected to the outer end of the first annular plate portion, a second annular plate portion falling radially inward from the second cylindrical portion, and an inner circumference of the second annular plate portion A third cylindrical portion that is provided on the outer side in the axial direction and faces the extension of the inner ring substantially in parallel with a required gap, and the sensor is disposed at one circumferential position of the second cylindrical portion. A sensor pocket is provided so as to be opposed to the pulsar ring, and the sensor is sandwiched and attached between the first annular plate portion and the second annular plate portion, and a third cylinder of the support ring. A sealing device is attached between the portion and the extension portion .
[0013]
In short, in the present invention, first, the support ring is used only for sensor mounting, and the pulsar ring is mounted directly on the rotation side member to be mounted without using the support ring. I am doing so. As a result, the number of component parts can be reduced. Moreover, if the attachment to the object to be attached to the pulsar ring is direct, there is no fear of deformation of the support ring that can occur in the conventional example using the support ring, so that the arrangement position of the pulsar ring can be appropriately managed, and the pulsar ring It becomes easy to manage the facing gap between the sensor and the sensor accurately and stably.
[0014]
Further, as in claim 2, if a sealing device is provided between the outer end of the support ring used for sensor attachment and the extension of the rotation side member to be attached to the pulsar ring, the sensor and pulsar ring The opposing gap can be concealed from the outside, and external foreign matter can be prevented from entering the opposing gap.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
The details of the present invention will be described based on embodiments shown in the drawings.
[0016]
1 to 3 show an embodiment of the present invention. 1 is an exploded perspective view of the rotational speed detection device, FIG. 2 is a longitudinal sectional view showing a hub unit equipped with the rotational speed detection device of FIG. 1, and FIG. 3 is an enlarged view around the rotational speed detection device of FIG. It is.
[0017]
First, the structure of the hub unit illustrated as a use object of the rolling bearing with a rotational speed detection apparatus of this invention is demonstrated. 2 and 3, 1 is a hub unit, 2 is a drive axle of an automobile, and 3 is an axle case of the automobile.
[0018]
The hub unit 1 is of a type that is attached to a drive axle 2 of an automobile, and includes a hub wheel 4 and a bearing device 5.
[0019]
The hub wheel 4 includes an annular plate portion 4a to which a wheel (not shown) is attached, and a shaft portion 4b in which the drive axle 2 is spline-fitted to the shaft center portion. A bearing device 5 is externally mounted on the outer peripheral surface of the shaft portion 4 b of the hub wheel 4.
[0020]
The bearing device 5 is composed of a double-row outward angular ball bearing that uses the outer peripheral surface of the shaft portion 4b of the hub wheel 4 as one inner ring, and is a single-row inner ring 5a that is press-fitted and fitted to the outer periphery of the shaft portion 4b. A single outer ring 5b having two rows of raceway grooves, a plurality of balls 5c arranged in two rows, and two crown-shaped cages 5d and 5d. A radially outward flange 5e is provided on the outer periphery of the outer ring 5b, and is fixed to the axle case 3 via the flange 5e. That is, the bearing device 5 is used in a form in which the outer ring 5b is not rotated and the inner ring 5a is rotated.
[0021]
The rotational speed detection device 6 according to the present invention is attached to one shaft end portion of the bearing device 5 of such a hub unit 1.
[0022]
The rotational speed detection device 6 includes a pulsar ring 10 and a sensor 20, and in this embodiment, a so-called active type is adopted.
[0023]
The pulsar ring 10 includes a cylindrical plastic magnet 11 provided with magnetic poles having different polarities alternately in the circumferential direction, and a base 12 made of a nonmagnetic material integrally polymerized on the inner circumferential side thereof. This plastic magnet 11 is a well-known one, but the required angle region in the circumferential direction is alternately set to an S pole using a synthetic metal injection molded product mixed with magnetic powder or a magnetic metal material such as sintered ferrite as a base material. It is manufactured by magnetizing the N pole.
[0024]
The sensor 20 is a known Hall IC. Although not shown in detail, the Hall IC has a structure in which an IC chip is molded with a protective cover made of synthetic resin. In this embodiment, the protective cover of the sensor 20 is connected to a rectangular main body 21 in which an IC chip is embedded, and is connected to the main body 21 in a state of facing the main body 21 through a required gap substantially in parallel. It has a structure including a U-shaped locking piece 22 and is formed to be substantially U-shaped when viewed from the side. The sensor 20 has an IC chip embedded so that the lower surface of the main body 21 is the sensor surface. And the convex part 23 is provided in the required position of the inner surface of the latching piece 22, and the cord wire 24 is pulled out from the upper surface of the main-body part 21. As shown in FIG.
[0025]
The pulsar ring 10 is directly attached to the outer peripheral surface of the shaft end of the inner ring 5a of the bearing device 5, and the sensor 20 is required in the circumferential direction of the pulsar ring 10 with respect to the shaft end of the outer ring 5b of the bearing device 5. It is indirectly attached to the position via the support ring 40 in a state of being opposed to the radial direction in a non-contact manner.
[0026]
In the case of such a mounting form, the support ring 40 protrudes from the shaft end of the outer ring 5 b of the bearing device 5, so that the sensor 20 attached to the support ring 40 directly contacts the inner ring 5 a of the bearing device 5. In order to oppose the pulsar ring 10 to be attached in the radial direction, in this embodiment, the axial end of the inner ring 5a of the bearing device 5 to which the pulsar ring 10 is attached is axially considered in consideration of the overhanging dimension of the support ring 40. The pulsar ring 10 is directly attached to the outer peripheral surface of the extension portion 5f. As an example of a method for attaching the pulsar ring 10, two layers of the base material 12 and the base 12 that can be the plastic magnet 11 are attached to the outer peripheral surface of the extension portion 5f of the inner ring 5a by baking. Thus, the S pole and the N pole are alternately magnetized in the required circumferential region of the base material that can be the plastic magnet 11. Thus, if the pulsar ring 10 is directly attached to the outer peripheral surface of the inner ring 5a having high shape accuracy, the pulsar ring 10 is positioned with high accuracy in the radial direction. However, it is necessary to manage the position in the axial direction when baking the pulsar ring 10 against the inner ring 5a.
[0027]
The support ring 40 is made of an annular iron plate that is press-formed in a plurality of stages. The support ring 40 includes a first cylindrical portion 41 that is press-fitted to the inner peripheral surface of the shaft end of the outer ring 5 b of the bearing device 5, and a first annular plate portion that rises radially outward from the first cylindrical portion 41. 42, a second cylindrical portion 43 connected to the outer end of the first annular plate portion 42, a second annular plate portion 44 falling radially inward from the second cylindrical portion 43, and a second annular plate portion 44. And a third cylindrical portion 45 facing the extension portion 5f of the inner ring 5a of the bearing device 5 substantially in parallel with a required gap. A sensor pocket 46 having an opening penetrating inward and outward in the radial direction is provided at one place in the circumferential direction of the second cylindrical portion 43, and the second annular plate portion 44 is in the same phase position as the sensor pocket 46. Is provided with a rectangular engagement hole 47 penetrating inward and outward in the axial direction. The opening shape of the engagement hole 47 is set so that the convex portion 23 of the sensor 20 is engaged.
[0028]
Next, a procedure for attaching the sensor 20 to the support ring 40 will be described. That is, the main body 21 of the sensor 20 is inserted into the sensor pocket 46 of the support ring 40 from the radial direction, and the main body 21 of the sensor 20 is inserted into the first and second annular plate portions 42 and 44 of the support ring 40. In the meantime, the locking piece 22 of the sensor 20 is placed outside the second annular plate portion 44, and the sensor 20 is continuously pressed to engage the convex portion 23 of the locking piece 22 with the support ring 40. What is necessary is just to engage with the hole 47. In such a state, since the main body portion 21 of the sensor 20 is sandwiched between the first and second annular plate portions 42 and 44 of the support ring body 40, the posture of the sensor 20 becomes stable, and the sensor 20 The engaging piece 22 is hooked on the second annular plate portion 44 and the convex portion 23 of the sensor 20 is engaged with the engaging hole 47 of the support ring 40, so that the sensor 20 does not need to be easily detached. become. With such an attachment configuration, the sensor 20 is positioned with high accuracy in the axial direction, the radial direction, and the circumferential direction.
[0029]
After the sensor 20 is attached to the support ring 40 in this way, when the support ring 40 is attached so as to be along the shaft end of the outer ring 5 b of the bearing device 5, the sensor surface of the sensor 20 becomes the bearing device 5. The pulsar ring 10 attached to the inner ring 5a faces the pulsar ring 10 from the radial direction through a required gap. Since the opposing gap between the pulsar ring 10 and the sensor 20 in this state can be positioned and attached with high accuracy as described above, it can be managed with high accuracy. The sensor 20 may be attached before or after the support ring 40 is mounted on the bearing device 5.
[0030]
Thereafter, the sealing device 50 is mounted between the third cylindrical portion 45 of the support ring 40 and the extension portion 5f of the inner ring 5a of the bearing device 5. The sealing device 50 has a structure in which a seal member 51 and a slinger 52 are combined, and the seal member 51 is distributed and press-fitted to the support ring 40 side and the slinger 52 is distributed to the inner ring 5a side of the bearing device 5 respectively. It has become so. Thus, if the sealing device 50 is provided outside the sensor 20 in the support ring 40, the facing gap between the pulsar ring 10 and the sensor 20 can be concealed from the outside, and foreign matter intrudes from the outside into the facing gap. Can be prevented.
[0031]
In order to remove the sensor 20 from the support ring 40, an operator bends the locking piece 22 of the sensor 20, and the convex portion 23 of the locking piece 22 is removed from the engagement hole 47 of the support ring 40. Just pull it out and pull it out.
[0032]
Next, the operation of the active type rotational speed detection device 6 will be described.
[0033]
When the pulsar ring 10 rotates synchronously with the rotation of the hub wheel 4, each magnetic pole of the pulsar ring 10 sequentially faces the non-rotating sensor 20. Here, since the direction of the magnetic field (lines of magnetic force) generated between the plurality of pairs of magnetic poles of the pulsar ring 10 is alternately reversed in the circumferential direction, the direction of the magnetic field passing through the sensor 20 with the rotation of the pulsar ring 10 is Inverts sequentially with a period according to the rotation speed. Therefore, the sensor 20 detects the above-described periodic reversal of the direction of the magnetic field, and outputs a pulse signal having a frequency corresponding to the rotational speed of the pulsar ring 10. This pulse signal is input to an ABS signal processing circuit (not shown). The hub wheel 4 is based on the pulse signal input from the sensor 20 and information such as the diameter of the wheel input in advance by the signal processing circuit. It is designed to recognize the rotational speed of the wheels attached to the.
[0034]
As described above, only the sensor 20 is attached using the support ring 40, and the pulsar ring 10 is directly attached to the inner ring 5a to be attached without using the support ring as in the prior art. Therefore, it is possible to simplify the configuration and contribute to the cost reduction, and it is possible to prevent the relative position between the pulsar ring 10 and the sensor 20 from being misaligned so that the detection accuracy by the sensor 20 can be maintained with high accuracy. Become.
[0035]
Moreover, in the above-described embodiment, the opposing gap between the pulsar ring 10 and the sensor 20 is concealed from the outside by providing the sealing device 50 outside the sensor 20 in the support ring 40. Intrusion of foreign matter can be prevented, and the detection accuracy of the sensor 20 can be maintained high over a long period of time.
[0036]
Further, in the above embodiment, considering the case where the inner ring 5a of the bearing device 5 to which the pulsar ring 10 is attached is made of a magnetic material, the pulsar ring 10 is composed of a plastic magnet 11 and a base 12 made of a nonmagnetic material. By doing so, the inner ring 5 a is prevented from being magnetized by the plastic magnet 11. Incidentally, if the inner ring 5a is magnetized, the metal wear powder inside the bearing adheres to the raceway groove of the inner ring 5a and is easily caught between the ball 5c and the inner ring 5a, thereby hindering the rolling characteristics of the ball 5c. There is concern about becoming. Such a problem can be avoided by using the pulsar ring 10 as described above.
[0037]
In addition, this invention is not limited only to the said embodiment, Various application and deformation | transformation can be considered.
[0038]
(1) In the above embodiment, the pulsar ring 10 has a two-layer structure of the plastic magnet 11 and the base 12. However, when the member to be attached to the pulsar ring 10 is a nonmagnetic material, the pulsar ring 10 is replaced with the plastic magnet 11. It is possible to have a single layer structure.
[0039]
(2) In the above embodiment, the configuration of the sealing device 50 disposed at the outer end of the support ring 40 may be of any form, and some may not use this sealing device 50. It is included in the present invention. If the sealing device 50 is not used, although not shown, the inner peripheral edge of the second annular plate portion 44 of the support ring 40 is extended toward the inner ring 5a to form a non-contact sealed portion, or the second annular plate portion A rubber lip may be provided on the extended edge of 44 so as to be in contact with the inner ring 5a.
[0040]
(3) In the above embodiment, the rotational speed detection device 6 is used for the hub unit 1 for a driving axle of an automobile, but it is also used for a well-known driven axle hub unit (not shown). Can do.
[0041]
(4) Although the Hall element is used as the sensor 20 in the above embodiment, a magnetoresistive element can be used.
[0042]
【The invention's effect】
In the rolling bearing with a rotational speed detection device according to the invention of claim 1 , only the sensor is attached using the support ring, and the support ring is not used on the rotation side member to which the pulsar ring is attached. Because it can be directly attached to the sensor, the structure can be simplified and the cost can be reduced. In addition, it is possible to prevent the pulsar ring from being displaced and to prevent the gap between the pulsar ring and the sensor. The detection accuracy by the sensor can be maintained with high accuracy such as being able to be optimized.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view showing a rotational speed detection device according to an embodiment of the present invention. FIG. 2 is a longitudinal sectional view showing a hub unit equipped with the rotational speed detection device of FIG. Enlarged view around the detector [Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Hub unit 2 Drive axle 3 Axle case 4 Hub wheel of hub unit 5 Bearing device 5a of hub unit Inner ring of bearing device (equivalent to rotation side member)
5b Outer ring of bearing device (equivalent to non-rotating side member)
6 Rotational Speed Detection Device 10 Pulsar Ring 20 of Rotational Speed Detection Device Sensor 21 of Rotational Speed Detection Device Sensor Body 40 Support Ring 46 Sensor Ring Sensor Pocket

Claims (1)

A hub wheel comprising an annular plate portion to which the wheel is attached and a shaft portion;
An inner ring as a rotation side member fitted on the outer periphery of the shaft portion;
An outer ring as a non-rotating side member arranged concentrically with the hub wheel and the inner ring,
A pulsar ring attached to the inner ring and a sensor attached to the outer ring for detecting the rotation of the pulsar ring, and a rotational speed detecting device for detecting the rotational speed of the inner ring with respect to the outer ring,
The inner ring is integrally formed with an extension portion extending outward in the axial direction from the outer end portion in the axial direction of the outer ring at the outer end portion in the axial direction,
The pulsar ring is attached to the outer peripheral surface of the extension part,
An annular support ring extending outward in the axial direction is attached to the axially outer end of the outer ring,
The support ring is made of an annular iron plate press-molded in a plurality of stages, and rises radially outward from the first cylindrical portion that is press-fitted into the inner peripheral surface of the shaft end of the outer ring. A first annular plate portion that is in contact with an end face of the outer ring; a second cylindrical portion that is connected to the outer end of the first annular plate portion; and a second annular plate that falls radially inward from the second cylindrical portion. And a third cylindrical portion that is provided on the outer side in the axial direction of the inner circumference of the second annular plate portion and faces the extension portion of the inner ring substantially in parallel with a required gap therebetween,
A sensor pocket to which the sensor is mounted so as to face the pulsar ring is provided at one place in the circumferential direction of the second cylindrical portion,
The sensor is mounted sandwiched between the first annular plate portion and the second annular plate portion,
A rolling bearing with a rotational speed detection device , wherein a sealing device is attached between the third cylindrical portion of the support ring and the extension portion .

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