JP2005337751A - Rotation supporting apparatus with rotation angle detecting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure capable of sufficiently securing the reliability of the detection of angle of rotation and sufficiently achieving compactness in size and low costs. <P>SOLUTION: Single magnetic poles (the south pole or the north pole) having different polarities from each other are arranged in both side surfaces of a circular encoder 2 to form one of the side surfaces as a surface to be detected 13. With the encoder 2 supported at a rotating wheel not shown in Fig., the center axis of the surface to be detected 13 is inclined to the center axis of the rotating wheel. Detecting surfaces 18 and 18 of first and second sensors (magnetic detection sensors) 3 and 4 supported at a fixed wheel not shown in Fig. are each opposed to parts in the surface to be detected 13 out of phase circumferencially by 90 degrees from each other. It is possible to compute the angle of rotation of the encoder 2 by an arithmetic circuit 5 supported at the fixed wheel on the basis of output of the sensors 3 and 4. By adopting such a constitution, the objective is achieved. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The rotation support device with a rotation angle detection device according to the present invention is incorporated, for example, in a steering device of an automobile and used to detect the rotation angle of the steering shaft.

  2. Description of the Related Art An automobile steering device is configured by supporting a steering shaft with a rolling bearing such as a deep groove type ball bearing inside a circular steering column supported on the lower side of a dashboard. When the steering angle is given to the front wheels, the steering shaft is rotated based on the operation of the steering wheel.

  Conventionally, a power steering apparatus has been widely used so that the steering wheel can be operated with a light force. Some of such power steering devices detect the rotation angle of the steering shaft and adjust the assist force by a hydraulic cylinder or an electric motor based on the detection signal. Therefore, such a power steering device incorporates a rotation angle detection device for detecting the rotation angle of the steering shaft. However, if a device independent of the rolling bearing is used as this rotation angle detection device, the number of parts increases, resulting in inconvenience such as troublesome assembly work. Therefore, in order to prevent the occurrence of such inconvenience, it is preferable to use the rotation angle detection device that is configured integrally with the rolling bearing.

  Conventionally, for example, those described in Patent Documents 1 and 2 are known as a rotation support device with a rotation speed detection device in which the rotation speed detection device and the rolling bearing as described above are integrally configured. Among these, the first example of the conventional structure described in Patent Document 1 is formed by supporting an optical encoder on a rotating wheel constituting a rolling bearing and an optical sensor on a fixed wheel, and rotating together with the rotating wheel. The rotation angle of the optical encoder can be detected by the optical sensor. In the second example of the conventional structure described in Patent Document 2, a cylindrical surface (detected surface) that is eccentric with respect to the rotation center axis of the rotating wheel is formed on a part of the rotating wheel that constitutes the rolling bearing. Forming and supporting two or more position detection sensors with respect to the fixed ring in a state of being spaced apart from each other in the circumferential direction, and the radial position of the detected surface detected by each of these position detection sensors Based on the above, the rotation angle of the rotating wheel can be detected freely.

  However, in the case of the first example of the conventional structure described above, if foreign matter such as lubricant or dust adheres to the detection surface of the optical encoder, the output of the optical sensor changes, so the reliability of rotation angle detection is reduced. To do. Therefore, it is necessary to provide a protective structure for keeping the detected surface of the optical encoder clean, and it is difficult to reduce the size and cost. In the case of the second example of the conventional structure described above, if foreign matter such as lubricant or dust adheres to the surface to be detected formed on the rotating wheel, the amount of the foreign matter attached is detected by the sensors. Since the radial position of the portion changes, the reliability of the rotation angle detection decreases. Therefore, it is necessary to provide a protective structure for keeping the detected surface clean, and it is difficult to reduce the size and the cost. Furthermore, in the case of the second example of the conventional structure described above, the detected surface is formed directly on a part of the rotating wheel. For this reason, a general-purpose track ring cannot be used as the rotating wheel, and a dedicated track ring needs to be manufactured, resulting in an increase in manufacturing cost.

JP-A-9-297151 JP 2000-171239 A

  The rotation support device with a rotation angle detection device of the present invention realizes a structure that can sufficiently ensure the reliability of rotation angle detection and that can sufficiently achieve downsizing and cost reduction in view of the circumstances as described above. Invented accordingly.

A rotation support device with a rotation angle detection device of the present invention includes a stationary wheel, a rotation wheel, a plurality of rolling elements, an annular encoder, at least one sensor, and an arithmetic circuit.
Among these, the stationary wheel has a stationary side track on the stationary side peripheral surface, and does not rotate during use.
Further, the rotating wheel has a rotating side track on the rotating side peripheral surface opposed to the stationary side peripheral surface, and rotates during use (in addition to the rotation continuously performed in one direction, both within a predetermined angle range). Including rotation performed appropriately in the direction).
Each of the rolling elements is provided between the stationary side track and the rotation side track so as to freely roll.
The encoder is supported by the rotating wheel and has an annular detection surface.
The sensor is supported by the stationary wheel and has a detection surface opposed to a part of the detection surface in the circumferential direction.
The arithmetic circuit calculates the rotation angle of the rotating wheel based on the output of the sensor.
In particular, in the rotation support device with a rotation angle detection device of the present invention, the detected surface is a surface in which the same magnetic pole (S pole or N pole) is arranged over the entire circumference. The sensor changes the magnitude of the output in accordance with the magnitude of the detected magnetism. Furthermore, the interval between the detected surface and the detection surface changes according to the rotation angle of the encoder.

  In the case of the rotation support device with a rotation angle detection device of the present invention configured as described above, when the rotation angle of the encoder with respect to the sensor changes due to the rotation of the rotation wheel with respect to the stationary wheel, according to this rotation angle, The output of this sensor changes. Accordingly, the rotation angle of the rotating wheel can be detected by the arithmetic circuit based on the output of the sensor.

  In the case of the present invention, even if foreign matter such as lubricant or dust adheres to the detected surface of the encoder, since the foreign matter is a non-magnetic material, a magnetic field formed around the detected surface is not generated. There is no change. Therefore, the rotation angle of the rotating wheel can be accurately detected. That is, in the case of the present invention, the reliability of the rotation angle detection can be sufficiently ensured without providing a protective structure for keeping the detected surface clean. As a result, in the case of the present invention, it is possible to reduce the size and the cost because the protective structure can be omitted.

  Further, in the case of the present invention, the detected surface is not directly formed on a part of the rotating wheel, and this detected surface is provided on a part of the encoder separate from the rotating wheel. For this reason, a general-purpose track ring can be used as the rotating wheel. Therefore, the cost can be reduced also from this aspect.

When carrying out the present invention, preferably, as described in claim 2, the detection surface of the encoder is an annular plane, and the detection surface of the sensor is provided on a part of the detection surface in the circumferential direction. It is made to oppose regarding the axial direction of a stationary wheel and a rotating wheel. Further, in order to change the interval between the detected surface and the detecting surface in accordance with the rotation angle of the encoder, the center axis of the detected surface is set to the rotating wheel while the encoder is supported on the rotating wheel. It is inclined with respect to the central axis.
Alternatively, as described in claim 3, the detection surface of the encoder is a cylindrical surface, and the detection surface of the sensor is opposed to a part of the detection surface in the circumferential direction with respect to the radial direction of the stationary wheel and the rotating wheel. Let In addition, in order to change the interval between the detection surface and the detection surface according to the rotation angle of the encoder, the detection surface is used as the central axis of the rotation wheel while the encoder is supported on the rotation wheel. Eccentric.
If these structures are adopted, the structure of the present invention can be easily realized.

Further, when implementing the present invention, more preferably, as described in claim 4, the encoder is disposed between the axial end surface of the stationary wheel and the axial end surface of the rotating wheel in the radial direction.
By adopting such a configuration, at least a part of the encoder can be disposed between the stationary side peripheral surface of the stationary wheel and the rotational side peripheral surface of the rotating wheel. As a result, further miniaturization can be achieved.

Moreover, when implementing this invention, More preferably, as described in claim 5, two sensors, a first sensor and a second sensor, are used as the sensors. The detection surfaces of the sensors are respectively opposed to portions of the detection target surface of the encoder that are different from each other with respect to the circumferential direction (for example, as described in claim 6, portions in which the phases in the circumferential direction are shifted from each other by 90 degrees).
By adopting such a configuration, the calculation of the rotation angle by the arithmetic circuit can be performed based on the outputs of the two sensors, so that the reliability of the rotation angle detection can be improved.

In carrying out the invention described in claims 5 to 6 described above, preferably, as described in claim 7, the arithmetic circuit is influenced by the temperature based on the outputs of the first and second sensors. It is assumed that it has a function of calculating a rotation angle corrected for.
By adopting such a configuration, the rotation angle can be accurately detected even when the magnetic force of the encoder and the sensitivity of the first and second sensors change due to temperature changes.

Moreover, when implementing this invention, More preferably, as described in claim 8, the first to fourth four sensors are used as sensors. At the same time, these four sensors are divided into two groups. In each set, the detection surfaces of the two sensors constituting the set are opposed to the portions of the detection target surface of the encoder whose circumferential phases are shifted from each other by 180 degrees. As described, the circumferential phase of each set is shifted 90 degrees from each other).
By adopting such a configuration, the calculation of the rotation angle by the arithmetic circuit can be performed based on the outputs of the four sensors, so that the reliability of the rotation angle detection can be further improved.

Further, when the inventions described in the above eighth to ninth aspects are carried out, preferably, as described in the tenth aspect, an arithmetic circuit is obtained for each of the above groups, and each of these two groups is configured. It is assumed that it has a function of calculating a rotation angle in which the influence of temperature is corrected based on the difference in output of each sensor.
By adopting such a configuration, even when the magnetic force of the encoder and the sensitivity of each sensor change due to a temperature change, the rotation angle can be detected accurately.

Further, when the present invention is carried out, it is more preferable that the arithmetic circuit is supported on the stationary wheel as described in claim 11.
By adopting such a configuration, the rotation support device with a rotation angle detection device can be handled integrally including the arithmetic circuit, and the work of assembling at the place of use can be easily performed.

Further, when the present invention is implemented, more preferably, as described in claim 12, when the rotation angle range of the rotating wheel with respect to the stationary wheel is less than 360 degrees as a use condition, the rotation angle is calculated as an arithmetic circuit. If the calculation result is output as an analog signal, and if it is 360 degrees or more, the arithmetic circuit having the function of integrating the number of rotations is used.
In this way, when the rotation angle range is less than 360 degrees, the arithmetic circuit can be made at a relatively low cost. On the other hand, when the rotation angle range is 360 degrees or more, the rotation angle of the rotating wheel can be obtained by digitally processing the sensor output and obtaining the change tendency and the integrated value of the change.

  1 to 4 show a first embodiment of the present invention corresponding to claims 1, 2, 4, 5, 6, 7, 11, and 12. The rotation support device with a rotation angle detection device of this embodiment includes a rolling bearing 1, an encoder 2, a first sensor 3 and a second sensor 4, and an arithmetic circuit 5. In the case of the present embodiment, the rolling bearing 1 is a single row deep groove type ball bearing, and has an outer ring 7 that is a stationary ring having a deep groove type outer ring raceway 6 on the inner peripheral surface, and a deep groove type on the outer peripheral surface. A plurality of inner rings 9 having inner ring raceways 8, which are rotating wheels, and are provided between the outer ring raceways 6 and the inner ring raceways 8 so as to be freely rollable while being held by a cage 10. It consists of individual balls 11.

  The encoder 2 is formed in a ring shape by a material (magnetic rubber) in which a powder of a ferromagnetic material such as ferrite is mixed in rubber, and is magnetized in the axial direction. The direction of magnetization is the same for the encoder 2 as a whole. Accordingly, single magnetic poles (S poles or N poles) having different polarities are disposed over the entire surface on both side surfaces of the encoder 2 in the axial direction. Such an encoder 2 is supported on one end portion (the right end portion in FIG. 1) of the inner ring 9 through a cored bar 12. The core metal 12 is formed in an annular shape as a whole by subjecting a magnetic metal plate such as a mild steel plate such as SPCC to a pressing process. The outer peripheral surface and one axial side surface (left side surface in FIG. 1) of the encoder 2 are attached and fixed to a holding portion having an L-shaped cross section provided in the outer half portion.

  In particular, in the case of the present embodiment, as shown in an exaggerated manner in FIG. 2 with the encoder 2 supported on one end portion of the inner ring 9 (through the core metal 12) as described above, the encoder 2 { The center axis X of the detected surface (the right side surface in FIGS. 1 and 2) 13} of the encoder 2 is inclined with respect to the center axis Y of the inner ring 9 by a predetermined angle α (for example, α = 1 to 2 degrees). I am letting. Furthermore, in the case of the present embodiment, by restricting the dimension of the encoder 2 in the radial direction, the encoder 2 is connected to one end surface of the outer ring 7 (right end surface in FIG. 1) and the inner ring 9 in the radial direction. It can be arranged between the first end face (the right end face in FIG. 1). Thereby, in the case of the present embodiment, as shown in FIG. 1, the axial half of the encoder 2 (the left half in FIG. 1) is separated from the inner peripheral surface of the outer ring 7 and the outer periphery of the inner ring 9. It is made to approach between the surfaces to reduce the size in the axial direction.

  In addition, each of the first and second sensors 3 and 4 has a magnetic detection element such as a Hall element or a magnetoresistive element that changes the output magnitude according to the magnitude of the detected magnetism. The magnetic detection elements of the sensors 3 and 4 are of the same type. Each of the first and second sensors 3 and 4 is supported on one end portion of the outer ring 7 via a support ring 14. The support ring 14 is formed in an annular shape by pressing a metal plate or the like, and has a cylindrical portion 15 and a flange portion 16 protruding radially outward from an intermediate portion of the cylindrical portion 15. And an annular portion 17 bent at a right angle inward in the radial direction from the leading edge (the right edge in FIG. 1) of the cylindrical portion 15. Then, the base half (the left half in FIG. 1) of the cylindrical portion 15 is fitted into one end portion of the outer ring 7 by an interference fit, and the side surface of the flange portion 16 is abutted against one end surface of the outer ring 7. In this way, axial positioning is achieved.

  The first and second sensors 3 and 4 are respectively fixed to the inner side surface (left side surface in FIG. 1) of the annular ring portion 17 with an adhesive or the like. In this state, as shown in FIG. 3, the detection surfaces (left side surface in FIG. 1, back side surface in FIG. 3) 18 and 18 of the first and second sensors 3 and 4 are respectively connected to the encoder 2. The detected surface 13 is opposed to a portion whose phases in the circumferential direction are shifted from each other by 90 degrees. At the same time, the detection surfaces 18 and 18 are arranged in the same virtual plane orthogonal to the central axis Y of the inner ring 9. Thereby, in the case of a present Example, the space | interval of the to-be-detected surface 13 of the said encoder 2 and the detection surfaces 18 and 18 of said 1st, 2nd sensors 3 and 4 is made into these 1st, 2nd each sensor 3, 4 is different from each other. At the same time, the interval between the detection surface 13 and the detection surfaces 18 and 18 is changed in accordance with the rotation angle of the encoder 2.

The arithmetic circuit 5 calculates the rotation angle of the encoder 2 based on the outputs of the first and second sensors 3 and 4. Such an arithmetic circuit 5 is fixed to a portion of the inner surface of the circular ring portion 17 that is separated from the first and second sensors 3 and 4 with an adhesive or the like. As a result, the arithmetic circuit 5 can be handled integrally with the rolling bearing 1. In this state, the arithmetic circuit 5 can receive the outputs of the first and second sensors 3 and 4 through the wires 20 and 21 as shown in FIG.
In the case of the illustrated example, the other end (left end in FIG. 1) opening of the rolling element installation space constituting the rolling bearing 1 is closed by a shield plate 22.

  When the rotation support device with a rotation angle detection device of the present embodiment configured as described above is used, the outer ring 7 constituting the rolling bearing 1 is internally fitted and supported on a fixed portion such as a steering column, and the inner ring 9 is also supported. It is externally supported by a rotating shaft such as a steering shaft. In particular, in the case of the present embodiment, when the outer ring 7 is internally fitted and supported on the fixed portion, the tip half of the pin 23 (the portion protruding from the outer peripheral surface) planted on the outer peripheral surface of the outer ring 7. ) Is engaged with an engaged portion such as a slit formed in the fixed portion. This prevents the outer ring 7 supporting the first and second sensors 3 and 4 from rotating with respect to the fixed portion, and the circumference of the first and second sensors 3 and 4. A reference position for the direction is determined.

  In this state, when the encoder 2 supported on the inner ring 9 rotates together with the rotation shaft, the outputs of the first and second sensors 3 and 4 change according to the rotation angle of the encoder 2, respectively. That is, in this embodiment, as shown in FIG. 4, a pair of sinusoidal signals whose phases are shifted by 90 degrees are obtained as the outputs of the first and second sensors 3 and 4. . Therefore, in the case of the present embodiment, based on the outputs of the first and second sensors 3 and 4, the arithmetic circuit 5 causes the encoder 2 to rotate (rotation angle of the rotating shaft with respect to the housing). Is calculated.

  When the present invention is implemented, the rotation angle of the encoder 2 as described above can be calculated based only on the output of one of the first and second sensors 3 and 4. . However, when the rotation angle of the encoder 2 is calculated based on only the output of one of the sensors in this way, the magnetic force of the encoder 2 and the sensitivity of the first and second sensors 3 and 4 are affected by the influence of temperature change. If the angle changes, the rotation angle may not be detected accurately. Therefore, in the case of the present embodiment, by calculating the rotation angle of the encoder 2 based on the outputs of both the sensors 3 and 4 as described above, the influence of the temperature change is corrected, and the rotation angle is calculated. It is designed so that it can be detected accurately. For this purpose, the arithmetic circuit 5 specifically outputs the output (sin wave) of the first sensor 3 indicated by the solid line a in FIG. 4 and the output (cos) of the second sensor 4 indicated by the broken line b in FIG. The rotation angle θ of the encoder 2 is calculated by calculating sin θ / cos θ = tan θ and further calculating the inverse function of tan θ.

  Then, the calculation result of the rotation angle θ as described above is sent from the arithmetic circuit 5 to a controller constituting the target device such as a power steering device. When the present embodiment is implemented, it is preferable that the calculation circuit 5 calculate the rotation angle θ when the rotation angle range of the inner ring 9 with respect to the outer ring 7 is less than 360 degrees. Use the one that outputs the result as an analog signal. On the other hand, when the angle is equal to or greater than 360 degrees, the arithmetic circuit 5 that outputs the calculation result of the rotation angle θ and the integration result of the number of rotations is used. In this way, when the rotation angle θ is less than 360 degrees, the arithmetic circuit 5 can be configured at low cost. On the other hand, when the rotation angle θ is 360 degrees or more, not only the rotation angle of the inner ring 9 but also the number of rotations is obtained.

  In the case of the rotation support device with the rotation angle detecting device of the present embodiment configured and operated as described above, even if a lubricant such as grease or foreign matter such as dust adheres to the detected surface 13 of the encoder 2, these Since the foreign matter is a non-magnetic material, the magnetic field formed around the detected surface 13 does not change. Therefore, the rotation angle of the encoder 2 can be accurately detected. That is, in the case of the present embodiment, the reliability of rotation angle detection can be sufficiently ensured without providing a protective structure for keeping the detected surface 13 clean. As a result, in the case of the present embodiment, it is possible to reduce the size and the cost because the protective structure can be omitted. Further, in the case of the present embodiment, the detected surface 13 is not directly formed on a part of the inner ring 9, but the detected surface 13 is formed on a part of the encoder 2 separate from the inner ring 9. doing. For this reason, a general-purpose track ring can be used as the inner ring 9. Therefore, the cost can be reduced also from this point.

  Next, FIGS. 5 to 7 show a second embodiment of the present invention corresponding to claims 1, 3, 4, 5, 6, 7, 11, and 12. In the case of the present embodiment, the encoder 2a is magnetized in the radial direction, and the direction of the magnetization in the radial direction is the same over the entire circumference. Therefore, single magnetic poles (S pole or N pole) having different polarities are arranged over the entire circumference on both the inner and outer circumferential surfaces of the encoder 2a. In the case of the present embodiment, the encoder 2a is supported on one end of the inner ring 9 (through the metal core 12a), as shown in FIG. The center axis X of the surface (outer peripheral surface) 13a} is shifted parallel to the center axis Y of the inner ring 9 by δ. That is, the encoder 2a is eccentric with respect to the inner ring 9.

  In the case of this embodiment, the first and second sensors 3 and 4 are attached and fixed to the inner peripheral surface of the cylindrical portion 15 constituting the support ring 14 fitted and fixed to one end of the outer ring 7a. . In this state, as shown in FIG. 7, the detection surfaces 18 and 18 of the first and second sensors 3 and 4 have a phase in the circumferential direction of the detection surface 13a of the encoder 2a. It is made to oppose the part which mutually shifted | deviated 90 degree | times. At the same time, the detection surfaces 18 and 18 are arranged so as to be in contact with a single virtual cylindrical surface centered on the central axis Y of the inner ring 9. Thereby, also in the case of the present embodiment, the distance between the detected surface 13a of the encoder 2a and the detection surfaces 18 and 18 of the first and second sensors 3 and 4 is set to the first and second sensors 3 respectively. 4 are different from each other. At the same time, the distance between the detection surface 13a and the detection surfaces 18, 18 is changed in accordance with the rotation angle of the encoder 2a. In the case of the present embodiment, the outer ring 7a has a ball 24 on the outer peripheral surface instead of the pin 23 (see FIG. 1) as a member for engaging with an engaged portion such as a slit formed in the housing. Have been planted.

  Also in the case of the rotation support device with the rotation angle detection device of the present embodiment configured as described above, when the encoder 2a supported on the inner ring 9 rotates together with the rotation shaft, the outputs of the first and second sensors 3 and 4 are output. Changes in accordance with the rotation angle of the encoder 2a. That is, also in the present embodiment, a pair of sinusoidal signals as shown in FIG. 4 are obtained as outputs of the first and second sensors 3 and 4. Therefore, also in the case of the present embodiment, as in the case of the above-described first embodiment, an arithmetic circuit (not shown) supported on the inner surface of the support ring 14 based on the outputs of the first and second sensors 3 and 4. The rotation angle of the encoder 2a can be calculated accurately. In particular, in the case of the present embodiment, the encoder 2a and the first and second sensors 3 and 4 are arranged so as to overlap each other in the radial direction. Compared to the structure of the first embodiment described above, the axial size can be reduced. The configuration and operation of the other parts are the same as in the case of the first embodiment.

  Next, FIG. 8 shows Embodiment 3 of the present invention corresponding to claims 1, 2, 3, 4, 8, 9, 10, 11, 12. The overall structure of the rotation support device with the rotation angle detection device of the present embodiment is substantially the same as that of the first embodiment described above except for the structure of the sensor and the arithmetic circuit. In the case of the present embodiment, first to fourth four sensors 25 to 28 are used as sensors. The detection surfaces of the sensors 25 to 28 are made to face each other in the axial direction at equal circumferential positions on the detected surface (side surface) of the encoder 2. Then, the first sensor 25 and the third sensor 27, which are positioned opposite to each other in the radial direction (the phases of the circumferential arrangement are shifted from each other by 180 degrees), are combined into one set. The output difference can be calculated by the first arithmetic circuit 29. Similarly, the second sensor 26 and the fourth sensor 28 that are located on the opposite sides with respect to the radial direction are set as one set, and the output difference between the two sensors 26 and 28 can be calculated by the second arithmetic circuit 30. I have to. A pair of output differences calculated by the first and second arithmetic circuits 29 and 30 are input to the third arithmetic circuit 31. In the case of the present embodiment, the pair of output differences are made to correspond to the pair of waveforms (sensor outputs a and b) shown in FIG. The rotation angle θ of the encoder 2 is calculated by the same calculation method as in the first embodiment.

  In the case of the present embodiment in which the rotation angle θ is calculated in this way, even if the output of each of the sensors 25 to 28 changes due to the influence of temperature change, the waveforms (sensor outputs a and b) shown in FIG. The center of each waveform (the center of the sensor output value) does not drift only by changing the amplitude of. For this reason, the origin position of the rotation angle (and further the number of rotations) can be obtained with high accuracy. Therefore, in the case of the present embodiment, not only the detection of the relative angle shown in the above-described Embodiments 1 and 2, but also when the sensor is turned on under the influence of the temperature change, It is possible to calculate the position accurately. As a result, the reliability of rotation angle detection can be improved.

  In the case of carrying out the present invention, the rolling bearing is not limited to the single row deep groove type ball bearing shown in the first and second embodiments, and various rolling bearings can be employed. Further, the encoder is not limited to an annular one having the same thickness dimension between the detected surface and the back surface thereof as shown in the first and second embodiments. The output of the sensor can be changed according to the rotation angle of the encoder, such as an annular one whose thickness dimension is changed periodically in the circumferential direction (for example, 360 degrees as one cycle) or an elliptical one. As long as it can be used, various shapes can be adopted.

FIG. 2 is a half sectional view showing Example 1 of the present invention. The perspective view of an encoder which shows the arrangement | positioning relationship between a rolling bearing and an encoder. The schematic diagram seen from the right side of FIG. 1 which shows the arrangement | positioning relationship between an encoder and each 1st, 2nd sensor. The figure which shows the output of each 1st, 2nd sensor. Sectional drawing which shows the half part which shows Example 2 of this invention. The perspective view of an encoder which shows the arrangement | positioning relationship between a rolling bearing and an encoder. FIG. 6 is a schematic diagram showing the positional relationship between the encoder and the first and second sensors, as viewed from the right side of FIG. 5. The figure similar to FIG. 3 which shows Example 3 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rolling bearing 2, 2a Encoder 3 1st sensor 4 2nd sensor 5 Arithmetic circuit 6 Outer ring track 7, 7a Outer ring 8 Inner ring track 9 Inner ring 10 Cage 11 Ball 12, 12a Core metal 13, 13a Detected surface 14 Support ring 15 Cylindrical part 16 collar part 17 annular part 18 detection surface 20 wiring 21 wiring 22 shield plate 23 pin 24 ball 25 first sensor 26 second sensor 27 third sensor 28 fourth sensor 29 first arithmetic circuit 30 second arithmetic circuit 31 Third arithmetic circuit

Claims (12)

  A stationary wheel that has a stationary side track on the stationary side circumferential surface and does not rotate during use; a rotating wheel that has a rotational side track on the rotational side circumferential surface facing the stationary side circumferential surface and rotates during use; and A plurality of rolling elements provided between the stationary side track and the rotating side track so as to roll freely, an annular encoder supported by the rotating wheel and having an annular detection surface, and the stationary wheel And at least one sensor that is supported so that its detection surface faces a part of the detected surface in the circumferential direction, and an arithmetic circuit that calculates the rotation angle of the rotating wheel based on the output of the sensor. A rotation support device with a rotation angle detection device, wherein the surface to be detected is a surface in which the same magnetic pole is arranged over the entire circumference, and the sensor outputs a magnitude corresponding to the magnitude of the detected magnetism. The distance between the detected surface and the detection surface is Rotational angle detecting apparatus with rotary supporting device, characterized in that changes according to the rotation angle of the encoder.   The detection surface of the encoder is an annular plane, and the detection surface of the sensor is opposed to a part of the detection surface in the circumferential direction with respect to the axial direction of the stationary wheel and the rotating wheel. In order to change the distance from the detection surface according to the rotation angle of the encoder, the center axis of the detection surface is inclined with respect to the center axis of the rotation wheel while the encoder is supported on the rotation wheel. The rotation support device with a rotation angle detection device according to claim 1.   The detection surface of the encoder is a cylindrical surface, and the detection surface of the sensor is opposed to a part of the detection surface in the circumferential direction with respect to the radial direction of the stationary wheel and the rotating wheel. The surface to be detected is decentered with respect to the central axis of the rotating wheel in a state where the encoder is supported by the rotating wheel in order to change the distance from the surface according to the rotation angle of the encoder. Item 2. A rotation support device with a rotation angle detection device according to Item 1.   The rotation support device with a rotation angle detection device according to any one of claims 1 to 3, wherein the encoder is disposed between the axial end surface of the stationary wheel and the axial end surface of the rotating wheel with respect to the radial direction.   Two sensors, a first sensor and a second sensor, are used as sensors, and the detection surfaces of the first and second sensors are opposed to different portions of the detected surface of the encoder in the circumferential direction. The rotation support device with a rotation angle detection device according to any one of claims 1 to 4.   In the detected surface of the encoder, the phase difference between the portion facing the detection surface of the first sensor and the portion facing the detection surface of the second sensor in the circumferential direction is 90 degrees. The rotation support device with the described rotation angle detection device.   The rotation support device with a rotation angle detection device according to any one of claims 5 to 6, wherein the arithmetic circuit has a function of calculating a rotation angle in which the influence of temperature is corrected based on outputs of the first and second sensors. .   As the sensors, first to fourth four sensors are used, and these four sensors are divided into two sets, and each set has a detection surface of two sensors constituting its own set. The rotation support device with a rotation angle detection device according to any one of claims 1 to 4, wherein the rotation detection device is opposed to a portion of the detection target surface of the encoder whose phase in the circumferential direction is shifted by 180 degrees.   The rotation support device with a rotation angle detection device according to claim 8, wherein phases in the circumferential direction of each set are shifted from each other by 90 degrees.   The arithmetic circuit has a function of calculating a rotation angle obtained by correcting the influence of temperature based on a difference between outputs of two sensors constituting each set obtained for each set. A rotation support device with a rotation angle detection device as described above.   The rotation support device with a rotation angle detection device according to claim 1, wherein the arithmetic circuit is supported by a stationary wheel.   As a usage condition, when the rotation angle range of the rotating wheel with respect to the stationary wheel is less than 360 degrees, a calculation circuit that outputs the calculation result of the rotation angle as an analog signal is used. The rotation support device with a rotation angle detection device according to any one of claims 1 to 11, wherein a device having a function of integrating the number of rotations is used as the arithmetic circuit.

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