JP4443252B2 - Bearing with rotation sensor - Google Patents

Description

  The present invention relates to a bearing with a rotation sensor, which is formed by mounting a rotation sensor on a rolling bearing and used for various devices.

A conventionally known bearing with a rotation sensor is a bearing having a large sensor installation space such as a deep groove ball bearing or the like (for example, Patent Document 1).
A general configuration of a bearing with a rotation sensor is shown in FIG. In the figure, a rotation sensor bearing 20 is a rolling bearing 21 including an inner ring 22, an outer ring 23, a rolling element 24, and a cage 25, in which a rotation sensor 31 is installed. The rotation sensor 31 is configured by mounting an annular magnetic encoder 26 on an inner ring 22 that is a rotation-side raceway, and mounting a magnetic sensor 27 on an outer ring 23 that is a fixed-side raceway so as to face the magnetic encoder 26. ing. As the magnetic sensor 27, a Hall element or a Hall IC is used. The magnetic encoder 26 is made of, for example, a rubber magnet and has N poles and S poles alternately magnetized in the circumferential direction as shown in FIG.

  As shown in FIG. 6, the magnetic sensor 27 is resin-molded while being inserted into the resin case 28, and is fixed to the outer ring 23 by fitting the resin case 28 to the outer ring 23 via the metal case 29. ing. As shown in FIG. 7, the magnetic sensor 27 includes two sensors 27a and 27b arranged so that the output phase difference (electrical angle) is 90 °. By configuring the rotation sensor 31 in this way, the magnetic sensor 27 detects a magnetic change of the magnetic encoder 26 as the inner ring 22 rotates, and the detection signal is an incremental signal whose phase is shifted by 90 ° as shown in FIG. Rotation pulse signal. From this signal, the rotation speed and rotation direction of the inner ring 22 can be known.

The rotation sensor-equipped bearing configured as described above has features such as being small in size, requiring no assembly adjustment, and being robust.
JP 2002-40037 A

  However, there is no example of a conventional bearing with a rotation sensor that is applied to a thin bearing, particularly a needle bearing, in which it is difficult to secure a sensor installation space. In the bearing 20 with the rotation sensor described above with reference to FIG. 6, the magnetic sensor 27 and the magnetic encoder 26 are mounted on the fixed-side raceway ring 23 and the rotation-side raceway ring 22 through various interposition members, so that it is thin like a needle bearing. A rolling bearing cannot secure a sensor space for mounting the magnetic sensor 27 and the magnetic encoder 26, and is difficult to apply.

  An object of the present invention is to provide a bearing with a rotation sensor that can be applied to a thin rolling bearing such as a needle bearing.

Bearing assembly sensor of the invention includes a stationary side raceway ring, and the rolling body, in a rolling bearing and a cage for holding the rolling elements, the rolling bearing consists of a needle bearing, the stationary bearing ring The rolling element is made to be rollable with a shell-type outer ring made of a pressed product of a steel plate, with the outer diameter surface of the rotating shaft, which is a rotating side member incorporating the rolling bearing, and the inner diameter surface of the fixed-side bearing ring as the raceway surface. , before Symbol detector provided inside the axial direction than the end surface of the fixed bearing ring, in the rotary shaft, the detector and the position opposed to the center of rotation around the center of the concentric of the stationary side raceway ring A rotor serving as a rotation detected portion of a rotating eccentric ring or a multipolar cam-shaped ring is disposed , the detector is a winding type detector, and the retainer and the detector are arranged on an inner diameter surface of the fixed-side raceway ring. Located between and the winding of the detector It is provided with a protective member formed of a ring-shaped plate member to prevent contact with the retainer.
According to this configuration, since the rotation detection part is a rotor of an eccentric ring or a multipolar cam-shaped ring, the rotation detector constituted by the rotor and the detector can have a small radial dimension. Therefore, the detector can be arranged on the inner side in the axial direction from the end face of the fixed-side bearing ring and can be directly attached to the inner or outer periphery of the bearing ring, and an interposition member for attachment is not necessary. As a result, the rotation detector can be further miniaturized. Therefore, it can be applied to a thin rolling bearing such as a needle bearing.

In the present invention, the inner diameter side end of the shaft受径direction before Symbol detector may as located on the outer diameter side than the outer diameter of the rotatable member to the rolling elements roll along the outer periphery.
In this configuration, since the inner diameter side end of the detector is located on the outer diameter side of the outer diameter of the rotation side member, the detector does not interfere with the rotation side member when the bearing is incorporated into the rotation side member. . Therefore, the rotation sensor-equipped bearing can be easily incorporated into the rotation side member.

Before Symbol detector Ru detector der winding type. High detection accuracy can be obtained with a winding type detector.

In the present invention, the width of the rotor facing the detector may be larger than the yoke width of the detector.
If the rotor width is larger than the yoke width, it is possible to prevent the output of the rotation sensor from changing even if relative movement of the rotor and the yoke in the axial direction occurs.

In the present invention, the rotor comprising a rotating portion to be detected before Symbol eccentrics or multipole cam profile wheels may as fit in the inner diameter side of the outer circle of the rotary-side member to which the rolling elements roll along the outer periphery.
If the rotor fits inside the outer diameter circle of the rotation side member, the rotor does not interfere with the bearing when the bearing is incorporated into the rotation side member, so it is easy to incorporate the rotation sensor bearing into the rotation side member. Can be done.

In the present invention, the rolling elements may be arranged in two rows, and the detector may be provided between the rolling members in both rows.
When the detector is disposed between the two rows of rolling elements, the radial load acting on the raceway can be applied to both rows of rolling elements without deviation.

Shall have a cage for pre retain Kiten body, the detector and the winding-type detector, the inner surface of the stationary side raceway ring, positioned between said detector and said retainer, A protective member made of a ring-shaped plate material for preventing the winding of the detector from coming into contact with the cage is provided.
While the cage is axially movable, more protective member provided on the inner surface of the stationary side raceway ring, the winding of the detector is prevented from contacting the cage, allows protection of the detector .

  When the protective member is provided, the detector and the protective member may be attached to the stationary race as an integral part. Integration reduces the number of parts and assembly man-hours.

Bearing assembly sensor of the invention includes a stationary side raceway ring, and the rolling body, in a rolling bearing and a cage for holding the rolling elements, the rolling bearing consists of a needle bearing, the stationary bearing ring The rolling element is made to be rollable with a shell-type outer ring made of a pressed product of a steel plate, with the outer diameter surface of the rotating shaft, which is a rotating side member incorporating the rolling bearing, and the inner diameter surface of the fixed-side bearing ring as the raceway surface. , before Symbol detector provided inside the axial direction than the end surface of the fixed bearing ring, in the rotary shaft, the detector and the position opposed to the center of rotation around the center of the concentric of the stationary side raceway ring A rotor serving as a rotation detected portion of a rotating eccentric ring or a multipolar cam-shaped ring is disposed , the detector is a winding type detector, and the retainer and the detector are arranged on an inner diameter surface of the fixed-side raceway ring. Located between and the winding of the detector Since a protective member comprising a ring-shaped plate member to prevent contact with the retainer, mounting of the rotation sensor is ready to thin rolling bearing such as a needle bearing.

  A first embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1A, this bearing with a rotation sensor is provided with a rotation sensor 11 in a rolling bearing 1 provided with an outer ring 2 and a plurality of rolling elements 3 serving as fixed raceways. The rolling bearing 1 is a needle bearing. The outer ring 2 is made of a shell type, that is, a pressed product of a steel plate. The rolling element 3 is a needle roller. The plurality of rollers 3 are assembled so as not to be separated into pockets 4a provided at a plurality of locations in the circumferential direction of the cage 4. The outer ring 2 has flanges 5 and 6 on both sides. The roller 3 is allowed to roll with the outer diameter surface 10a of the rotating shaft 10 and the inner diameter surface 2a of the outer ring 2 as a raceway surface as the rotation side member into which the rolling bearing 1 is incorporated. The rotation sensor 11 includes a detector 12 provided on the inner side in the axial direction from the end face of the outer ring 2, that is, one flange portion 5, and a rotor 13 provided at a position facing the detector 12 of the rotation shaft 10. It consists of.

  The detector 12 is of a radial type and comprises a winding type detector. A cross-sectional view taken along line AA in FIG. 1A is shown in FIG. As shown in the figure, a plurality of teeth arranged in the circumferential direction are formed as a yoke 15 on the inner peripheral side of the annular magnetic body 14, and this yoke 15 is wound around the yoke 15 and serves as excitation and detection. The detector 12 is composed of the detection coil 16. The outer diameter dimension of the detector 12, that is, the outer diameter dimension of the magnetic body 14 is substantially the same as the inner diameter dimension of the outer ring 2, and this detector 12 is formed before the flange portion 5 at one end of the outer ring 2 is bent. Further, the magnetic body 14 is fixed to the outer ring 2 by press-fitting the magnetic body 14 into the inner surface 2 a of the outer ring 2. After the detector 12 is fixed, one end of the outer ring 2 is bent to form the flange portion 5. The inner diameter of the detector 12, that is, the inner diameter of the yoke 15 is larger than the outer diameter of the rotating shaft 10 which is the inner diameter of the rolling bearing 1, and is detected when the rolling bearing 1 is incorporated into the rotating shaft 10. The device 12 does not interfere with the rotating shaft 10.

  The rotor 13 serves as a rotation detected portion detected by the detector 12, and is located at a position facing the detector 12 on the outer periphery of the rotation shaft 10 (center O of the rotation shaft 10). ) And an eccentric ring that rotates around the center of rotation. That is, the rotor 13 that is an eccentric ring has an eccentric machining surface centered on a position O1 slightly deviated from the center O of the rotating shaft 10 at a position facing the detector 12 of the outer diameter surface 10a of the rotating shaft 10. Is. The rotor 13 is machined so that the rollers 3 fit on the inner peripheral side of the outer diameter circle of the rotating shaft 10 rolling on the outer periphery, and the rotor 13 is obstructed when the rolling bearing 1 is assembled into the rotating shaft 10. Never become. Further, the axial width W of the rotor 13 is sufficiently longer than the width Y of the yoke 15. Thereby, even if the outer ring 2 moves in the axial direction, the output of the rotation sensor 11 is prevented from changing.

  Further, a substrate 17 for collectively processing the wiring of the detection coil 16 is fixed to the side surface of the detector 12 that faces the outer ring flange 5. The substrate 17 is connected to an external electric processing circuit through a lead wire 19. It should be noted that the wiring may be directly drawn out without using the substrate 17.

  Between the retainer 4 and the detector 12, a protective member 18 fixed to the inner diameter surface 2a of the outer ring 2 is disposed. The protection member 18 is made of a ring-shaped plate material. The retainer 4 is movable in the axial direction, but the protection coil 18 is interposed between the retainer 4 and the detector 12 in this manner, so that the detection coil 16 of the detector 12 contacts the retainer 4. Is reliably prevented. Although the protection member 18 and the detector 12 are separated here, the protection member 18 may be formed integrally with the detector 12.

  According to the bearing with the rotation sensor having this configuration, an AC voltage of, for example, about 10 KHz is applied to the detection coil 16 when the rotation sensor 11 is operated. When the rotating shaft 10 rotates, the air gap between the yoke 15 and the rotor 13 constituting the detector 12, that is, the magnetic resistance of the detection coil 16 changes, and each rotation of the rotating shaft 10 has a sinusoidal shape for one cycle and is 90 ° relative to each other. The detection coil 16 is subjected to a winding process so that the detection coil 16 obtains two signals having a phase difference. By electrically processing this signal, the absolute position of the rotating shaft 10 can be detected with high resolution. The electrical processing here is the same as the well-known resolver conversion processing.

  As described above, in the bearing with the rotation sensor, the detector 12 is provided on the inner side in the axial direction from the flange portion 5 of the outer ring 2 that is the stationary side race ring, and the center of the outer ring 2 is located at a position facing the detector 12. Since the rotor 13 serving as the rotation detected portion of the eccentric wheel rotating around the rotation center concentric with the (center O of the rotation shaft 10) is disposed, even if the rolling bearing 1 is a thin needle bearing, the rotation sensor 11 The installation space can be easily secured, and the rotation sensor 11 can be assembled without difficulty.

  FIG. 2 is a cross-sectional view showing another embodiment of the present invention. In this embodiment, in the bearing with a rotation sensor of FIG. 1, the rotor 10 which is a rotation detected portion is a multipolar cam-shaped ring in which a plurality of convex portions are arranged in the circumferential direction. Here, the rotor 10 is a three-pole cam-shaped wheel. As a result, the change in the air gap between the yoke 15 of the detector 12 and the rotor 10 changes by three periods per rotation of the rotating shaft 10, and the resolution and position accuracy of rotation detection are further improved. Other configurations are the same as those of the first embodiment shown in FIG.

  FIG. 3 is a longitudinal sectional view showing still another embodiment of the present invention. This embodiment shows an example in which the rolling bearing 1 is a needle bearing in which rolling elements 3 are arranged in two rows in the bearing with a rotation sensor of FIG. The detector 12 is provided between the rollers 3 in both rows. Further, the protection member 18 is provided on both side surfaces of the detector 12. Other configurations are the same as those of the first embodiment shown in FIG.

FIG. 4 is a longitudinal sectional view showing a reference proposal example of the present invention. This reference proposal example shows an example in which the bearing with the rotation sensor shown in FIG. 1 is applied when the rolling bearing 1A is a needle bearing with an inner ring. In this example, the rolling bearing 1 </ b> A is a needle bearing having an inner ring 7 that is a rotating side raceway, in addition to the outer ring 2 that is a stationary side raceway and the rolling element 3. The outer diameter surface 7a of the inner ring 7 becomes a raceway surface of the roller 3 that is a rolling element. In addition, the rotor 13 </ b> A serving as a rotation detected portion is formed of an eccentric ring integrally formed at a position facing the detector 12 on the outer periphery of the inner ring 7. The rotor 13A composed of the eccentric ring rotates around the rotation center concentric with the center O of the outer ring 2 (also the center of the inner ring 7). The rotor 13A may be a multipolar cam-shaped wheel. Also in the case of this reference proposal example, the movement of the cage 4 in the axial direction is restricted by the protective member 18, but this is not restrictive, and the detector 12 has a structure in which the detection coil 16 and the cage 4 do not contact each other. Thus, the protection member 18 may be omitted. As shown in FIG. 1, the outer ring 2 may not have the flange 5 as shown in FIG. 1, and the protective member 18 and the detector 4 are fixed to the outer ring 2 by being press-fitted into the inner diameter surface 2a of the outer ring 2 from one end. Is done. Other configurations are the same as those of the first embodiment shown in FIG.

FIG. 5 is a longitudinal sectional view showing another reference proposal example of the present invention. Similarly to the case of FIG. 4, this reference proposal example shows an example in which the configuration of the bearing with the rotation sensor of FIG. 1 is applied to the case where the rolling bearing 1A is a needle bearing with an inner ring. The rotor 13 </ b> B serving as a rotation detected part is formed by press-fitting an eccentric ring made of a magnetic material into a thin part 7 b formed at a position facing the detector 12 on the outer periphery of the inner ring 7. The outer diameter surface of the inner ring thin portion 7 b is concentric with the center O of the inner ring 7. The rotor 13B may be a multipolar cam-shaped wheel. Other configurations are the same as those of the first embodiment shown in FIG.

In each of the above-described embodiments, the case where the present invention is applied to the rolling bearing 1 without a seal has been described. However, even in the case of a rolling bearing in which seals are provided on both inner sides of the outer ring 2 that is a stationary raceway, The bearing with a rotation sensor of the invention can be similarly applied. The present invention can also be applied when the fixed-side race is an inner ring.

(A) is a longitudinal cross-sectional view of the bearing with a rotation sensor which concerns on 1st Embodiment of this invention, (B) is the cross-sectional view. It is a cross-sectional view of a bearing with a rotation sensor according to another embodiment of the present invention. It is a cross-sectional view of a bearing with a rotation sensor according to still another embodiment of the present invention. It is a cross-sectional view of a bearing with a rotation sensor according to a reference proposal example of the present invention. It is a cross-sectional view of a bearing with a rotation sensor according to another reference proposal example of the present invention. It is a longitudinal cross-sectional view of a prior art example. It is a partial front view which shows the structure of the rotation sensor in the prior art example. It is an output waveform diagram of the same rotation sensor.

Explanation of symbols

1, 1A ... Rolling bearing 2 ... Outer ring (fixed raceway ring)
3 ... Roller (rolling element)
10 ... Rotating shaft (rotating side member)
DESCRIPTION OF SYMBOLS 12 ... Detector 13, 13A, 13B ... Rotor 15 ... Yoke 16 ... Detection coil 18 ... Protective member O ... Center of stationary-side bearing ring

Claims (7)

A fixed bearing ring, and rolling elements in a rolling bearing and a cage for holding the rolling elements, the rolling bearing consists of a needle bearing, shell type comprising the stationary bearing ring from steel stampings and of the outer ring, the rolling element inside diameter surface of the outer diameter surface and the stationary side raceway ring of the rotary shaft as the rotational-side member incorporating the rolling bearing as a track surface is freely rolling, the end face of the front Symbol stationary side raceway ring provided detector inside the axial direction than, in the rotary shaft, the detector and the position opposed to the eccentric wheel or multipole cam-shaped rotating around the rotational center and the center of the concentric of the stationary side raceway ring A rotor serving as a rotation detected portion of the ring, the detector is a winding type detector, and is positioned between the retainer and the detector on the inner diameter surface of the fixed-side raceway ring, Prevent the detector windings from contacting the cage Bearing with a rotation sensor having a protective member comprising a ring-shaped plate member. The bearing with a rotation sensor according to claim 1, wherein the rotor serving as the rotation detected portion is a multipolar cam-shaped ring in which a plurality of convex portions are arranged in a circumferential direction. Oite to claim 1 or claim 2, as the inner diameter side end of the shaft受径direction before Symbol detector, which is located on the outer diameter side than the outer diameter of the rotatable member to the rolling elements roll along the outer periphery Bearing with rotation sensor. Oite to any one of claims 1 to 3, wherein the width of said rotor facing the detector, the detector ones and the bearing with a rotation sensor is larger than the yoke width. Oite to any one of claims 1 to 3, polarized Kokorowa or multipole cam profile wheel rotor rotation the detected portion of the outer diameter of the rotatable member to the rolling elements roll along the outer periphery Bearing with rotation sensor that fits inside the inner diameter of the circle. Oite to any one of claims 1 to 3, arranged rolling elements in two rows, bearing with a rotation sensor provided with the detector during the rolling elements in both rows. Any Oite one of claims 1 to 6, bearing with a rotation sensor attached to the stationary side raceway ring and the protective member and the detector are integrally formed.

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