JP2006105750A - Magnetic encoder and bearing device for wheel provided with same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnetic encoder which capable of securing a magnetic characteristic guarantee range, excelling in productivity during vulcanization of a rubber and reducing the number of manufacturing processes and the costs as well as excelling in productivity for mounting it in a bearing or the like, without problem of engaging another magnetic encoder during the manufacturing processes or transportation. <P>SOLUTION: The magnetic encoder 11 is constituted by fixing the encoder rubber 13 to a core 12. The core 12 is made into a cross-sectional L shape having a press-in cylindrical part 12a and a standing plate part 12b extending from one end of the cylindrical part 12a to the outer diameter side. The encoder rubber 13 is fixed to the outer side surface of the standing plate part 12b of the core 12 and is made like a ring provided with magnetic poles arranged in the circumferential direction. The inner diameter of the encoder rubber 13 is smaller than the outer diameter of the cylindrical part 12a of the core 12, by 0.12 mm or more in terms of the radius, and is made larger than the inner diameter of the cylindrical part 12a. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic encoder used in a rotation detecting device for a bearing portion that rotates relatively, and a wheel bearing device including the same, for example, a rotation detecting device that detects front and rear wheel rotational speeds in an antilock brake system of an automobile. The present invention relates to a magnetic encoder that is a component part of a bearing seal to be mounted on a magnetic field.

  2. Description of the Related Art As a magnetic encoder that is attached to a bearing-side rotating ring, a permanent magnet is fixed to a core metal (for example, Patent Document 1). In this case, the metal core is an annular body having an L-shaped cross-sectional outline composed of a cylindrical portion serving as a press-fitting portion to the rotating raceway and a standing plate portion extending radially from one end of the cylindrical portion. Is done. As the permanent magnet, for example, a ring-shaped encoder rubber obtained by kneading magnetic powder and a rubber material is used, and this encoder rubber is vulcanized and bonded to one side surface of the upright portion of the core metal. The encoder rubber is magnetized with magnetic poles arranged in the circumferential direction.

In the magnetic encoder having such a configuration, for example, in a shape in which the standing plate portion of the core metal extends from one end of the cylindrical portion to the outer diameter side, the relationship between the inner diameter of the encoder rubber and the inner and outer diameters of the core metal cylindrical portion is The following three types are set.
(1) The inner diameter of the encoder rubber is set larger than the outer diameter of the cored bar cylindrical portion (Patent Document 1).
(2) Set the inner diameter of the encoder rubber to be the same as the inner diameter of the cylindrical core part.
(3) The inner diameter of the encoder rubber is arbitrarily set between the inner diameter and the outer diameter of the cored bar cylindrical portion.
JP 2003-269476 A

  However, in the magnetic encoder in which the relationship between the inner diameter of the encoder rubber and the inner and outer diameters of the core metal cylindrical portion is set as shown in (1), the magnetic properties of the encoder rubber in the radial direction are guaranteed by the increase in the inner diameter of the encoder rubber. The range (a range in which sufficient magnetic characteristics can be obtained for detection) becomes narrow on the inner diameter side, and desired magnetic characteristics may not be ensured.

  Further, in the magnetic encoder in which the relationship between the inner diameter of the encoder rubber and the inner and outer diameters of the core metal cylindrical portion is set as shown in (2), when the encoder rubber is vulcanized and bonded to the side surface of the core metal vertical plate portion, the core metal cylinder There is a risk of encoder rubber leaking to the inner diameter side of the shaped part. If there is this leakage, it will not be possible to secure a load for the magnetic encoder to escape from the bearing rotating side race. Therefore, in this case, it is necessary to prevent the leakage by vulcanizing and bonding the encoder rubber to the core metal stand plate portion in a state in which the core metal cylindrical portion is press-fitted into the mold imitating the bearing rotating side raceway. Yes, man-hours and costs increase.

  The magnetic encoder in which the relationship between the inner diameter of the encoder rubber and the inner and outer diameters of the cored bar cylindrical portion is set as shown in (3) has the following problems. That is, this type of magnetic encoder is generally handled in a state where a plurality of magnetic encoders 31 are stacked as shown in FIG. 9 in the manufacturing process, transportation, and bearing assembly process. At this time, if the inner diameter of the encoder rubber is arbitrarily set between the inner diameter and the outer diameter of the cylindrical core portion as in (3) above, the inner diameter of the encoder rubber 33 of the upper magnetic encoder 31 in FIG. The outer diameter surface of the cylindrical portion 32a of the cored bar 32 of the lower magnetic encoder 31 may bite into the end surface. When such bite occurs, in the bearing assembly process, the magnetic encoders 31 must be manually removed from the stacked magnetic encoder group one by one and supplied to the bearing, which increases the productivity of incorporation into the bearing. descend.

  The purpose of the present invention is to ensure the guaranteed range of magnetic properties, to improve the productivity during rubber vulcanization, to reduce the number of manufacturing steps and costs, and to eliminate the problem of biting into other magnetic encoders during the manufacturing process and transportation. An object of the present invention is to provide a magnetic encoder excellent in productivity built into a bearing and the like, and a wheel bearing device including the same.

A first magnetic encoder according to the present invention includes an L-shaped cored bar having a cylindrical part for press-fitting and a vertical plate part extending from one end of the cylindrical part to the outer diameter side, and the vertical plate of the cored bar. In a magnetic encoder composed of a ring-shaped encoder rubber fixed to the outer side surface of the section and provided with magnetic poles arranged in the circumferential direction, the inner diameter dimension of the encoder rubber is the outer diameter dimension of the cylindrical section of the cored bar. The radius is smaller than 0.12 mm and larger than the inner diameter of the cylindrical portion.
According to this configuration, it is possible to ensure the guaranteed range of magnetic properties, reduce manufacturing man-hours and costs, and prevent deterioration of productivity in the bearing.
Since the inner diameter dimension of the encoder rubber is smaller than the outer diameter dimension of the cored bar cylindrical portion, it is possible to widen the radial magnetic property guarantee range of the encoder rubber and easily secure desired magnetic characteristics.
Since the inner diameter of the encoder rubber is larger than the inner diameter of the core metal cylindrical portion, when the encoder rubber is vulcanized and bonded to the side surface of the core metal stand plate portion, the encoder rubber is attached to the inner surface of the core metal cylindrical portion. There is no risk of leakage, and there is no need for a process of vulcanizing and bonding the encoder rubber in a state in which the core metal cylindrical portion is press-fitted into the mold, thereby making it possible to reduce manufacturing man-hours and costs.
Also, since the inner diameter of the encoder rubber is 0.12 mm or more smaller than the outer diameter of the cylindrical cored bar, multiple magnetic encoders are stacked in the manufacturing process, transportation, and bearing assembly process. In the case of handling in the state, it is possible to avoid the outer diameter surface of the cylindrical portion of the core metal of the lower magnetic encoder from biting into the inner diameter end surface of the encoder rubber of the upper magnetic encoder. Since there is no such bite, there is no need to manually remove magnetic encoders one by one from the stacked magnetic encoder group and supply them to the bearing in the bearing assembly process. Decline can be prevented.
According to the test, the ease of occurrence of the bite depends on the difference in radius regardless of the inner diameter of the encoder rubber, and the radius between the inner diameter of the encoder rubber and the outer diameter of the cored bar cylindrical portion. If the difference is smaller than 0.12 mm, the above biting is likely to occur, but if it is larger than 0.12 mm, it is confirmed that the biting is difficult to occur.

The second magnetic encoder of the present invention is reverse to the first magnetic encoder. That is, the magnetic encoder includes a press-fitted cylindrical portion and an inverted L-shaped cored bar having a vertical plate extending from one end of the cylindrical part toward the inner diameter side, and an outer side of the vertical plate of the cored bar. In the magnetic encoder composed of a ring-shaped encoder rubber fixed to the side surface of the ring and provided with magnetic poles arranged in the circumferential direction, the outer diameter dimension of the encoder rubber is larger than the inner diameter dimension of the cylindrical portion of the core metal. And larger than 0.12 mm and smaller than the outer diameter of the cylindrical portion.
According to this configuration, similarly to the first magnetic encoder, it is possible to ensure a guaranteed range of magnetic characteristics, to reduce manufacturing man-hours and costs, and to prevent a reduction in productivity built into the bearing.
That is, since the outer diameter dimension of the encoder rubber is larger than the inner diameter dimension of the cored bar cylindrical portion, the radial magnetic property guarantee range in the encoder rubber can be widened, and desired magnetic characteristics can be easily secured.
Since the outer diameter of the encoder rubber is smaller than the outer diameter of the cored bar cylindrical part, when the encoder rubber is vulcanized and bonded to the side of the cored bar stand, the outer diameter of the cored bar cylindrical part There is no risk of the encoder rubber leaking to the side, and a process of performing vulcanization and adhesion of the encoder rubber in a state where the core metal cylindrical portion is press-fitted into the mold becomes unnecessary, and the number of manufacturing steps and costs can be reduced.
In addition, the outer diameter of the encoder rubber is larger than the inner diameter of the cylindrical core by 0.12 mm or more, so multiple magnetic encoders are stacked in the manufacturing process, transportation, and bearing assembly process. In the case of handling in the state, it can be avoided that the inner diameter surface of the cylindrical portion of the lower core of the magnetic encoder bites into the outer diameter end surface of the encoder rubber of the upper magnetic encoder. Since there is no such bite, there is no need to manually remove magnetic encoders one by one from the stacked magnetic encoder group and supply them to the bearing in the bearing assembly process. Decline can be prevented.

A seal with a magnetic encoder according to the present invention includes the first or second magnetic encoder according to the present invention and a seal member facing the inside of the magnetic encoder. The seal member includes a seal core and the seal core. An elastic body fixed to gold, and the elastic body has a plurality of seal lips that are in contact with the peripheral surface of the cylindrical portion and the side surface of the upright plate portion of the core of the magnetic encoder, and the magnetic encoder Is attached to one member which rotates relatively, and the sealing member is attached to the other member.
According to this configuration, since the magnetic encoder of the rotation detection device is also used as a component of the seal, a high sealing function can be provided without increasing the number of parts.

The wheel bearing device of the present invention includes an outer member having a double-row raceway surface on the inner periphery, an inner member having a raceway surface facing these raceway surfaces, and a double-row interposed between the opposing raceway surfaces. A wheel bearing comprising a rolling element and rotatably supporting a wheel with respect to a vehicle body, wherein the first magnetic encoder of the present invention is attached to the outer periphery of the inner member by press-fitting, or the second of the present invention A magnetic encoder is attached to the inner periphery of the outer member by press fitting, or a seal with a magnetic encoder according to the present invention is attached by press-fitting the encoder core and the seal core to the inner member or the outer member, respectively. Is.
According to this configuration, the magnetic encoder can be easily incorporated, and an excellent rotation detection function can be obtained by ensuring the guaranteed range of magnetic characteristics of the magnetic encoder of the present invention.

A first magnetic encoder according to the present invention includes an L-shaped cored bar having a cylindrical part for press-fitting and a vertical plate part extending from one end of the cylindrical part to the outer diameter side, and the vertical plate of the cored bar. In a magnetic encoder composed of a ring-shaped encoder rubber fixed to the outer side surface of the section and provided with magnetic poles arranged in the circumferential direction, the inner diameter dimension of the encoder rubber is larger than the outer diameter dimension of the cylindrical portion of the core metal. Because the radius is smaller than 0.12mm and larger than the inner diameter of the cylindrical part, the magnetic property guarantee range can be secured, the productivity at the time of rubber vulcanization is excellent, and the man-hours and costs can be reduced. There is no problem of biting in with other magnetic encoders during the process and transportation, and it is possible to improve the productivity of incorporation into bearings.
A second magnetic encoder according to the present invention includes a press-fitted cylindrical portion and a vertical L-shaped core bar having a vertical plate portion extending from one end of the cylindrical portion toward the inner diameter side, and the vertical plate of the core bar. In a magnetic encoder composed of a ring-shaped encoder rubber fixed to the outer side surface of the section and provided with magnetic poles arranged in the circumferential direction, the inner diameter dimension of the encoder rubber is larger than the outer diameter dimension of the cylindrical portion of the core metal. Because the radius is smaller than 0.12mm and larger than the inner diameter of the cylindrical part, the magnetic property guarantee range can be secured, the productivity at the time of rubber vulcanization is excellent, and the man-hours and costs can be reduced. There is no problem of biting in with other magnetic encoders during the process and transportation, and it is possible to improve the productivity of incorporation into bearings.

  A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows an example of a wheel bearing device provided with the magnetic encoder of this embodiment. This wheel bearing device 10 is of the third generation type, and includes an outer member 1 having double-row raceway surfaces 1a on the inner periphery, and an inner member 2 having raceway surfaces 2a facing these raceway surfaces 1a. And double row rolling elements 3 interposed between the opposed raceway surfaces 1a and 2a, and seals 8 and 9 at both ends for sealing the annular space between the inner and outer members 2 and 1. The seal 9 at one end has a magnetic encoder 11. The rolling element 3 consists of a ball or a roller, and a ball is used in this example.

  This wheel bearing device 10 is a double-row rolling bearing, more specifically, a double-row angular contact ball bearing. The inner member 2 includes a hub ring 5 and an inner ring 6 fitted to the outer periphery of the shaft portion. Thus, the raceway surfaces 2 a and 2 a of the rolling element rows are formed on the outer circumferences of the hub ring 5 and the inner ring 6, respectively. The hub wheel 5 has a wheel mounting flange portion 5 a on the outer periphery thereof, and a wheel (not shown) is attached to the flange portion 5 a with a bolt 7. The outer member 1 is attached to a housing (not shown) made of a knuckle or the like in the suspension device via the outer peripheral flange portion 1b. The rolling elements 3 are held by a holder 4 for each row.

  FIG. 2 shows an enlarged view of the seal 9 with a magnetic encoder. The seal 9 includes a magnetic encoder 11 and a seal member 14, and the magnetic encoder 11 or its core metal 12 serves as a slinger. The magnetic encoder 11 is attached to the rotating member of the outer member 1 and the inner member 2, and the seal member 14 is attached to the fixed member. In this example, since the inner member 2 is the rotation side and the outer member 1 is the fixed side, the magnetic encoder 11 is attached to the inner ring 6 of the inner member 2 and the seal member 14 is attached to the outer member 1. .

  The magnetic encoder 11 includes a cored bar 12 and an encoder rubber 13 fixed to the cored bar 12. The metal core 12 is a metal ring body having an L-shaped cross section having a cylindrical portion 12a for press-fitting and a standing plate portion 12b extending from one end of the cylindrical portion 12a to the outer diameter side. The magnetic encoder 11 is attached to the inner member 2 by press-fitting the shaped portion 12 a into the outer diameter surface of the inner ring 6 of the inner member 2. The encoder rubber 13 is a ring-shaped member obtained by kneading magnetic powder and a rubber material. The encoder rubber 13 is a side surface opposite to the protruding side of the cylindrical portion 12a of the standing plate portion 12b of the core metal 12 (facing the bearing outside). The magnetic poles aligned in the circumferential direction are magnetized. A rotation detection device for detecting the wheel rotation speed is configured by arranging a magnetic sensor 17 as shown in FIG. 2 so as to face the encoder rubber 13 in the magnetic encoder 11.

As shown in FIG. 3, the inner diameter φEi encoder rubber 13 is smaller than the outer diameter [phi] C _o of the core cylindrical portion 12a, the difference Δ is the radius 0.12mm or more. Also, the inner diameter φEi of the encoder rubber 13 is slightly larger than the inner diameter φC _i of the cored bar cylindrical portion 12a. The encoder rubber 13 has a hardness of 80 to 100 points (durometer hardness). The plate | board thickness of the metal core 12 is constant over the whole cylindrical part 12a and the standing board part 12b, and is 0.5 mm-0.7 mm.

  In FIG. 2, the seal member 14 includes a seal metal core 15 and an elastic body 16 vulcanized and bonded to the seal metal core 15. The seal core 15 is a metal ring having an inverted L-shaped cross section having a cylindrical portion 15a for press-fitting and a standing plate portion 15b extending from one end of the cylindrical portion 15a to the inner diameter side. The cylindrical portion 15 a is attached to the outer member 1 by press-fitting and fitting to the inner diameter surface of the outer member 1. The seal member 14 integrally includes a side lip 16a that is in sliding contact with the cored bar upright portion 12b of the magnetic encoder 11 and radial lips 16b and 16c that are in sliding contact with the cylindrical cored portion 12a. The lips 16 a to 16 c are provided as a part of the elastic body 16 that is vulcanized and bonded to the seal core 15. The seal member 14 is configured such that an elastic body 16 is held in a fitting portion between the seal core 15 and the outer member 1. That is, the elastic body 16 has a tip cover portion 16d that covers from the inner diameter surface of the cylindrical portion 15a of the seal metal core 15 to the outer diameter of the tip portion. It is interposed in the fitting part with the member 1. The cylindrical portion 15a of the seal core 15 and the core plate upright portion 12b of the magnetic encoder 11 are opposed to each other with a slight radial gap, and the labyrinth seal 18 is configured by the gap.

  According to the wheel bearing device 10 having this configuration, the rotation of the inner member 2 rotating together with the wheel is detected by the magnetic sensor 17 via the magnetic encoder 11 attached to the inner member 2, and the wheel rotation speed is detected. Is done.

The magnetic encoder 11, as shown in FIG. 3, the inner diameter .phi.E _i of encoders rubber 13, small or 0.12mm radius than the outer diameter [phi] C _o of the core cylindrical portion 12a, and the core metal cylinder Since it is larger than the inner diameter dimension φC _i of the shaped portion 12a, it is possible to ensure a guaranteed range of magnetic properties, reduce manufacturing man-hours / costs, and prevent deterioration of productivity in the bearing. That is, the inner diameter .phi.E _i of the encoder rubber 13, is smaller than the outer diameter [phi] C _o of the core cylindrical portion 12a, sufficient magnetic characteristics can be obtained in the magnetic properties guaranteed range (detection of radial direction of the encoder rubber 13 Range) can be widened and desired magnetic properties can be easily secured.
Since the inner diameter dimension φE _i of the encoder rubber 13 is larger than the inner diameter dimension φC _i of the core metal cylindrical portion 12a, when the encoder rubber 13 is vulcanized and bonded to the side surface of the core metal vertical plate portion 12b, the core metal There is no risk of the encoder rubber 13 leaking to the inner diameter surface side of the cylindrical portion 12a, and the process of performing vulcanization adhesion of the encoder rubber 13 with the core metal cylindrical portion 12a being press-fitted into the mold becomes unnecessary. Can be reduced.

Further, the inner diameter .phi.E _i of encoders rubber 13, since than the outer diameter [phi] C _o of the core cylindrical portion 12a, the difference Δ is such that the radius 0.12mm or more, and smaller, prepared When handling a plurality of magnetic encoders 11 in a stacked state as shown in FIG. 4 in the process, transportation, and bearing assembly process, the core bar of the lower magnetic encoder 11 is placed on the inner diameter end surface of the encoder rubber 13 of the upper magnetic encoder 11. It is possible to avoid the outer diameter surface of the cylindrical portion 12a from biting in. Since there is no such bite, there is no need to manually remove the magnetic encoder 11 one by one from the stacked magnetic encoder group and supply it to the bearing in the bearing assembly process. Can be prevented. Specifically, incorporation into the wheel bearing device 10 can be easily performed.

The value that the difference Δ is 0.12 mm or more is a value that is confirmed by a test as a minimum dimension that can reliably bite. As a result of the test, even if the diameter of the magnetic encoder 11 is different, if the above difference Δ is the same, the biting prevention property does not change. In any case, the minimum dimension of the difference Δ that can reliably bite is It was 0.12 mm. The difference Δ is preferably as large as possible to prevent biting. However, the extent to be larger than the inner diameter [phi] C _i of the inner diameter .phi.E _i metal core cylindrical portion 12a is that the difference is 0.1mm or more in radius, the metal core inner diameter side at the time of the vulcanization It is preferable from the viewpoint of preventing leakage of rubber material.

  Further, the magnetic encoder-equipped seal 9 having the above-described configuration can have a high sealing function without increasing the number of parts because the magnetic encoder 11 of the rotation detecting device is also used as a component of the seal 9.

Explain the test results. The following two types of tests (Test 1 and Test 2) were performed.
(Test 1)
In the magnetic encoder 11 described in conjunction with FIG. 3, the inner diameter .phi.E _i of the encoder rubber 13 as shown in Table 1, and the difference (radius step between the outer diameter [phi] C _o of the inner diameter .phi.E _i and the core cylindrical portion 12a ) A plurality of samples were classified into three types (specifications A, B, and C) having different Δs. The encoder rubber 13 has a hardness in the range of 80 to 100 points. The plate thickness of the cored bar 12 is 0.5 to 0.7 mm.
The test method is as follows. When the magnetic encoder 11 is transported in a stacked manner as shown in FIG. 4 and handled in the manufacturing process, the inner end face of the encoder rubber 13 of the upper magnetic encoder 11 is placed on the core metal cylindrical portion of the lower magnetic encoder 11. It was set as the method of observing the ease of generating that the outer diameter surface of 12a bites.
Of the numerical range indicating the radial step Δ in the table, 0.12 indicating the upper limit is less than 0.12.

  As a result of this test, as shown in the table, no biting occurred in any of the specification B classifications (examples where the radial step Δ was as large as 0.17 to 0.18 mm). The comparative example (specifications A and C) having a small step Δ of 0.11 to 0.12 mm had bite.

(Test 2)
Tests were performed on magnetic encoders 11 having different radial steps Δ as shown in Table 2 by the same test method as Test 1. Each magnetic encoder 11 serving as a specimen in this case has the same size, shape and material except that the radial step Δ is different.

As shown in Table 2, it was found that each example having a radial step Δ of 0.11 or less is likely to bite, but each example having a radial step Δ of 0.125 or more is less likely to bite. From this result, it can be seen that if the radial step Δ is 0.12 or more, the bite is unlikely to occur.
From the results of Test 1 and Test 2, regardless of the diameter size of the magnetic encoder 11, if the radial step Δ is 0.12 or more, it is difficult for bite to occur, but if it is less than 0.12, bite is likely to occur. I understand.

  Another embodiment of the present invention will be described with reference to FIGS. FIG. 5 shows an example of a wheel bearing device provided with the magnetic encoder of this embodiment. This wheel bearing device 10A is of the second generation type, and the inner member 2 is composed of a pair of split inner rings 2A and 2B, and a fixed axle is fitted to the inner diameter surfaces of these inner rings 2A and 2B. . That is, the inner member 2 is a fixed member. A raceway surface 2a of each rolling element row is formed on the inner rings 2A and 2B. On the other hand, the outer member 1 is a member on the rotation side, and is composed of a bearing outer ring that also serves as an integral hub wheel, and has a wheel mounting flange portion 1c on the outer periphery, and a wheel ( A bolt 7 is attached. The outer member 1 has the raceway surface 1a facing the double-row raceway surface 2a of the inner member 2, the double-row rolling elements 3 are interposed between the raceway surfaces 1a and 2a facing each other, and the inner and outer members 2 , 1 is provided with the seals 8 and 9A at both ends for sealing the annular space, as in the case of the wheel bearing device 10 of FIG. The seal 9A in this case also has a magnetic encoder 21.

  FIG. 6 shows an enlarged view of the seal 9A with a magnetic encoder. This seal 9A is composed of a magnetic encoder 21 and a seal member 24, and the magnetic encoder 21 or its core 22 is a slinger. The magnetic encoder 21 is attached to the rotating member of the outer member 1 and the inner member 2, and the seal member 24 is attached to the fixed member. In this example, since the outer member 1 is the rotation side and the inner member 2 is the fixed side, the magnetic encoder 21 is attached to the outer member 1, and the seal member 24 is attached to the inner member 2.

  The magnetic encoder 21 includes a cored bar 22 and an encoder rubber 23 fixed to the cored bar 22. The cored bar 22 is a metal ring having an inverted L-shaped cross section having a cylindrical portion 22a for press-fitting and a standing plate portion 22b extending from one end of the cylindrical portion 22a to the inner diameter side. The magnetic encoder 21 is attached to the outer member 1 by press-fitting the shaped portion 22 a into the inner diameter surface of the outer member 1. The encoder rubber 23 is a ring-shaped member obtained by kneading magnetic powder and a rubber material, and the side surface (surface facing the outside of the bearing) opposite to the protruding side of the cylindrical portion 22a of the upright plate portion 22b of the cored bar 22. The magnetic poles aligned in the circumferential direction are magnetized. The rotation sensor for detecting the wheel rotation speed is configured by arranging the magnetic sensor 17 as shown in FIG. 6 so as to face the encoder rubber 23 in the magnetic encoder 21.

As shown in FIG. 7, the outer diameter dimension φE _O of the encoder rubber 23 is larger than the inner diameter dimension φC _i of the cored bar cylindrical portion 22a, the difference Δ is 0.12 mm or more in radius, and the cored bar cylinder is smaller than the outer diameter [phi] C _o of Jo portion 22a.

  The seal member 24 includes a seal core 25 and an elastic body 26 vulcanized and bonded to the seal core 25. The seal metal core 25 is a metal ring having an L-shaped cross section having a cylindrical portion 25a for press-fitting and a standing plate portion 25b extending from one end of the cylindrical portion 25a to the outer diameter side. The cylindrical portion 25 a is attached to the inner member 2 by press fitting into the outer diameter surface of the inner member 2. The seal member 24 integrally includes a side lip 26a that is in sliding contact with the core metal upright plate portion 22b of the magnetic encoder 21 and radial lips 26b and 26c that are in sliding contact with the cylindrical core portion 22a. The lips 26 a to 26 c are provided as a part of the elastic body 26 that is vulcanized and bonded to the seal core 25. The seal metal core 25 has an elastic body 26 held in a fitting portion with the inner member 2. That is, the elastic body 26 has a tip cover portion 26d that covers from the outer diameter surface of the cylindrical portion 25a of the seal metal core 25 to the inner diameter of the tip portion, and this tip cover portion 26d It is interposed in the fitting portion with the member 2. The cylindrical portion 25a of the seal core 25 and the core plate upright portion 22b of the magnetic encoder 21 are opposed to each other with a slight radial gap, and the labyrinth seal 18A is configured by the gap.

  In the wheel bearing device 10A having this configuration, the rotation of the outer member 1 that rotates together with the wheel is detected by the magnetic sensor 17 via the magnetic encoder 21 attached to the outer member 1, and the wheel rotation speed is detected. The

As shown in FIG. 7, the magnetic encoder 21 has an outer diameter dimension φE _o of the encoder rubber 23 larger than the inner diameter dimension φC _i of the cored bar cylindrical portion 22a by a radius of 0.12 mm or more, and the cored bar cylinder is made smaller than the outer diameter [phi] C _o of Jo portion 22a, ensuring the magnetic properties guaranteed range, the reduction of manufacturing steps, cost, thereby enabling incorporation productivity of preventing deterioration in the bearing. That is, since the outer diameter dimension φE _o of the encoder rubber 23 is larger than the inner diameter dimension φC _i of the cored bar cylindrical portion 22a, the radial magnetic property guarantee range in the encoder rubber 23 (a magnetic characteristic sufficient for detection is obtained). Range) can be widened and desired magnetic properties can be easily secured.
Further, the outer diameter .phi.E _o encoder rubber 23, is made smaller than the outer diameter [phi] C _o of the core cylindrical portion 22a, when the encoder rubber 23 on the side surface of the core metal standing portion 22b to wear vulcanization The encoder rubber 23 does not leak to the outer diameter surface side of the cored bar cylindrical portion 22a, and the process of performing vulcanization adhesion of the encoder rubber 23 in a state where the cored bar cylindrical portion 22a is press-fitted into the mold is unnecessary. Manufacturing man-hours and costs can be reduced.
Further, since the outer diameter dimension φE _o of the encoder rubber 23 is larger than the inner diameter dimension φC _i of the cored bar cylindrical portion 22a by a radius of 0.12 mm or more, in the manufacturing process, transportation, and bearing assembly process, 8, when the plurality of magnetic encoders 21 are handled in a stacked state, the inner diameter surface of the cored bar cylindrical portion 22 a of the lower magnetic encoder 21 bites into the outer diameter end surface of the encoder rubber 23 of the upper magnetic encoder 21. Can be avoided reliably. Since there is no such bite, there is no need to manually remove the magnetic encoder 21 one by one from the stacked magnetic encoder group and supply it to the bearing in the bearing assembly process. Can be prevented. Specifically, it can be easily incorporated into the wheel bearing device 10A.

  In addition, although each said embodiment demonstrated about the case where it applied to the magnetic encoder with which a wheel bearing apparatus is equipped, the magnetic encoder of this invention is a magnetic encoder attached to common rolling bearings, such as a deep groove ball bearing, The present invention can also be applied to magnetic encoders attached to other rotating members.

It is sectional drawing of the wheel bearing apparatus provided with the magnetic encoder concerning 1st Embodiment of this invention. It is an expanded sectional view of the seal | sticker which uses the magnetic encoder as a component. It is explanatory drawing which shows each dimensional relationship in the magnetic encoder. It is sectional drawing which shows the stacked state of the same magnetic encoder. It is sectional drawing of the wheel bearing apparatus provided with the magnetic encoder concerning other embodiment of this invention. It is an expanded sectional view of the seal | sticker which uses the magnetic encoder as a component. It is explanatory drawing which shows each dimensional relationship in the magnetic encoder. It is sectional drawing which shows the stacked state of the same magnetic encoder. It is sectional drawing which shows the lamination | stacking state of the conventional magnetic encoder.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Outer member 1a ... Raceway surface 2 ... Inner member 2a ... Raceway surface 3 ... Rolling elements 9, 9A ... Seal 10,10A with a magnetic encoder ... Wheel bearing device 11 ... Magnetic encoder 12 ... Core metal 12a ... Cylindrical shape Part 12b ... Standing plate part 13 ... Encoder rubber 14 ... Sealing member 15 ... Sealing core 15a ... Cylindrical part 15b ... Standing plate part 16 ... Elastic body 16a ... Side lips 16b, 16c ... Radial lip 21 ... Magnetic encoder 22 ... Core Gold 22a ... Cylindrical portion 22b ... Vertical plate portion 23 ... Encoder rubber 24 ... Seal member 25 ... Seal core 25a ... Cylindrical portion 25b ... Vertical plate portion 26 ... Elastic body 26a ... Side lips 26b, 26c ... Radial lip

Claims (4)

  A metal core having an L-shaped cross section having a cylindrical portion for press-fitting and a vertical plate portion extending from one end of the cylindrical portion to the outer diameter side, and a circular shape fixed to the outer side surface of the vertical plate portion of the metal core In a magnetic encoder comprising a ring-shaped encoder rubber provided with magnetic poles arranged in the circumferential direction, the inner diameter dimension of the encoder rubber is smaller than the outer diameter dimension of the cylindrical portion of the core metal by 0.12 mm or more in radius, A magnetic encoder characterized in that it is larger than the inner diameter of the cylindrical portion.   A cylindrical part for press-fitting, and a core bar having an inverted L-shaped cross section having a standing plate part extending from one end of the cylindrical part to the inner diameter side, and a circle fixed to the outer side surface of the standing plate part of the core metal In a magnetic encoder composed of a ring-shaped encoder rubber provided with magnetic poles arranged in the circumferential direction, the outer diameter of the encoder rubber is 0.12 mm or more larger in radius than the inner diameter of the cylindrical portion of the core metal, The magnetic encoder is smaller than the outer diameter of the cylindrical portion.   A magnetic encoder according to claim 1 or 2 and a seal member facing the inside of the magnetic encoder, wherein the seal member includes a seal metal core and an elastic body fixed to the seal metal core. The elastic body has a plurality of seal lips that are in contact with the circumferential surface of the cylindrical portion of the core bar and the side surface of the upright plate portion of the magnetic encoder, and the magnetic encoder is attached to one member that rotates relatively. And a seal with a magnetic encoder, wherein the seal member is attached to the other member. An outer member having a double-row raceway surface on the inner periphery, an inner member having a raceway surface facing these raceway surfaces, and a double-row rolling element interposed between the opposing raceway surfaces, In the wheel bearing that supports the wheel rotatably,
The magnetic encoder according to claim 1 is attached to the outer periphery of the inner member by press-fitting, or the magnetic encoder according to claim 2 is attached to the inner periphery of the outer member by press-fitting, or the seal with a magnetic encoder according to claim 3. A wheel bearing device in which the encoder core and the seal core are pressed into the inner member or the outer member, respectively.

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