JP2017223528A - Torque detecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a torque detecting device which does not require mechanical adjustment at initial setting, has a simple structure, and can stably detect torque.SOLUTION: A torque detecting device 1 has an outer ring 2 and an inner ring 3 which can rotate mutually, and detects torque acting between the outer ring 2 and the inner ring 3. An elastic member 4 is provided, which directly or indirectly couples the outer ring 2 and the inner ring 3, and deforms according to the rotation displacement of the outer ring 2 and the inner ring 3. An angle sensor 40 detects rotation angles of the outer ring 2 and the inner ring 3. Torque calculating means 10 calculates torque from a detection value of the angle sensor 40.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a torque detection device used for detecting torque applied to a shaft, and more particularly to a technique for detecting torque applied to a joint or the like of an industrial robot.

  Patent Document 1 discloses a torque detection device that detects torque applied to a joint portion of an industrial robot. In this torque detection device, an outer ring and an inner ring are connected by a plurality of elastic beams, and a displacement is generated between a pair of inner ring protruding pieces and an outer ring that are arranged to protrude from the inner ring to the outer ring on the diameter side. The amount is measured by two displacement sensors, and the shaft torque acting on the inner and outer rings is detected from the two measured displacement amounts.

Japanese Patent No. 3136816

  The torque detection device disclosed in Patent Document 1 measures a displacement amount generated between a pair of inner ring projecting pieces and an outer ring with two displacement sensors, and thus a pair of inner ring projecting pieces in an initial setting. It is difficult to adjust the mechanical clearance between the outer ring and the outer ring. Further, Patent Document 1 does not describe a method for calculating torque from the values of two displacement sensors, but processing such as estimating the rotational displacement amount between the outer ring and the inner ring from the values of the two displacement sensors. Therefore, it is considered that the processing circuit becomes complicated.

  An object of the present invention is to provide a torque detection device that does not require mechanical adjustment at the time of initial setting and is capable of stable torque detection with a simple mechanism.

  A torque detection device according to the present invention includes an outer ring and an inner ring that are rotatable relative to each other, and detects torque acting between the outer ring and the inner ring, wherein the outer ring and the inner ring are directly or indirectly connected. An elastic member that is connected and deforms according to rotational displacement between the outer ring and the inner ring, an angle sensor that detects a rotation angle between the outer ring and the inner ring, and a torque calculation that calculates the torque from the detected value of the angle sensor And means 10.

  According to this configuration, when torque is applied between the outer ring and the inner ring, the elastic member connecting the outer ring and the inner ring is deformed, and rotational displacement is generated between the outer ring and the inner ring. The angle of this rotational displacement is detected by an angle sensor, and torque calculation means 10 calculates torque from the detected value. As described above, since the rotational displacement between the outer ring and the inner ring is directly detected, processing such as estimating the rotational displacement amount between the outer ring and the inner ring by using the values of the two displacement sensors as in the prior art is unnecessary. Can be simplified. In addition, since a minute rotational displacement between the outer ring and the inner ring is measured and converted into torque, mechanical adjustment after mounting the angle sensor is unnecessary.

In this invention, the angle sensor is provided on one of the outer ring and the inner ring and the magnetic poles are arranged in a circumferential direction, and the magnetic field of the magnetic encoder is provided on the other of the outer ring and the inner ring. The structure which has a magnetic sensor to detect may be sufficient.
When the angle sensor has a magnetic encoder and a magnetic sensor, the rotational displacement angle information is detected as a digital value, so that there is no output offset like an analog signal and stable torque output is possible.

When the angle sensor has a configuration including a magnetic encoder and a magnetic sensor, the magnetic encoder has at least one row of magnetic encoder tracks in which N poles and S poles are alternately magnetized,
The angle sensor is a high frequency obtained by electrically multiplying the angle of one pole pair of the N pole and the S pole of the magnetic encoder track from the magnetic signal output by the magnetic sensor due to the rotational displacement between the magnetic encoder and the magnetic sensor. A multiplying circuit 61 that generates a resolution pulse signal and a counter 62 that counts the pulse signal generated by the multiplying circuit 61 and sends the counted angle information to the torque calculation means 10 may be provided.
With this configuration, the rotation angle between the outer ring and the inner ring can be detected with high resolution, so that the torque acting between the outer ring and the inner ring can be accurately detected.

Further, when the angle sensor has a configuration including a magnetic encoder and a magnetic sensor, the magnetic encoder has a double-row magnetic encoder track in which N poles and S poles are alternately magnetized with different numbers of pole pairs. And the magnetic sensor has a plurality of detection units that respectively detect magnetic fields of the double-row magnetic encoder tracks,
The angle sensor detects a phase difference between magnetic signals output from the plurality of detection units of the magnetic sensor by rotational displacement between the magnetic encoder and the magnetic sensor, and the phase difference detection unit. An absolute angle calculation unit 52 that calculates the absolute angle of the rotational displacement based on the phase difference detected in 51, and a transmission unit 54 that sends the absolute angle information of the absolute angle calculation unit 52 to the torque calculation means 10. May be.
With this configuration, a double-row magnetic encoder track having a different number of magnetic pole pairs and a plurality of detection units of the magnetic sensor rotate relative to each other, thereby causing a phase shift between detection signals of the plurality of detection units. This phase difference is detected by the phase difference detection unit 51, and the absolute angle of the rotational displacement between the outer ring and the inner ring is calculated by the absolute angle calculation unit 52 based on the phase difference. The calculated absolute angle information is sent to the torque calculation means 10 by the transmission unit 54. Since the absolute angle between the outer ring and the inner ring is converted into torque, accurate torque can be obtained.

In this invention, the range in which the angle of the magnetic encoder can be detected may be a part of the circumference.
Since the outer ring and the inner ring are connected by an elastic member and only slightly rotate with each other, there is no problem even if the range in which the angle of the magnetic encoder can be detected is a part of the circumference.

In the present invention, the outer ring and the inner ring may be an outer ring and an inner ring of a bearing, respectively, and the angle sensor may be provided integrally with the bearing, and the bearing and the angle sensor may constitute a bearing with an angle sensor.
Thereby, a torque detection apparatus can be comprised using the existing shaft with an angle.

  A torque detection device according to the present invention includes an outer ring and an inner ring that are rotatable relative to each other, and detects torque acting between the outer ring and the inner ring, wherein the outer ring and the inner ring are directly or indirectly connected. An elastic member that is connected and deforms according to rotational displacement between the outer ring and the inner ring, an angle sensor that detects a rotation angle between the outer ring and the inner ring, and a torque calculation that calculates the torque from the detected value of the angle sensor Therefore, mechanical adjustment at the time of initial setting is unnecessary, and stable torque detection is possible with a simple mechanism.

It is sectional drawing fractured | ruptured in the plane which passes along the axial center of the mechanism part of the torque detection apparatus concerning one Embodiment of this invention. It is II-II sectional drawing of FIG. It is a figure which shows the magnetization pattern of the magnetic encoder of the torque detection apparatus, and shows the state seen from the III-III cross section of FIG. It shows a configuration of an angle sensor of the torque detection device. It is a figure which shows the relationship between the magnetization pattern of the magnetic encoder track | truck, and the magnetic signal which a magnetic sensor outputs. It is a block diagram of the torque calculation means of the torque detection device. It is sectional drawing fractured | ruptured in the plane which passes along the axial center of the mechanism part of the torque detection apparatus concerning different embodiment of this invention. It is VIII-VIII sectional drawing of FIG. It is a figure which shows the magnetization pattern of each magnetic encoder track | truck of the magnetic encoder of the same torque detection apparatus, and shows the state seen from the IX-IX cross section of FIG. It is sectional drawing fractured | ruptured in the plane which passes along the axial center of the mechanism part of the torque detection apparatus concerning further different embodiment of this invention. It is a XI arrow line view of FIG. It is sectional drawing fractured | ruptured in the plane which passes along the axial center of the mechanism part of the torque detection apparatus concerning further different embodiment of this invention. It is XIII-XIII sectional drawing of FIG. It is a figure which shows the magnetization pattern of the magnetic encoder of a different angle sensor. It is a structure of the angle sensor of FIG.

An embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view taken along a plane passing through the axis of a mechanism portion of a torque detector according to an embodiment of the present invention, and FIG. The torque detection device 1 includes a mechanism unit 1a and a processing circuit 1b. The processing circuit 1 b includes an angle calculation unit 50 and a torque calculation unit 10. The angle calculation means 50 and the torque calculation means 10 are each configured by mounting a microcomputer and an electronic circuit on a circuit board, or are constituted by a personal computer. The processing circuit 1b may be provided in the mechanism unit 1a or may be provided outside connected by wiring. Details of the processing circuit 1b will be described later.

  The mechanism unit 1 a includes an outer ring 2 and an inner ring 3. An inner diameter surface 2a of the outer ring 2 and an outer diameter surface 3a of the inner ring 3 are in slidable contact with each other in the circumferential direction, and the outer ring 2 and the inner ring 3 are rotatable relative to each other. As shown in FIG. 2, the outer ring 2 and the inner ring 3 are connected by a plurality of elastic members 4. In the illustrated example, four elastic members 4 are arranged at equal intervals in the circumferential direction. Both ends of each elastic member 4 are inserted into the mounting groove 2b of the outer ring 2 and the mounting groove 3b of the inner ring 3, respectively. The mounting groove 2b of the outer ring 2 is at the bottom of the notch 2c formed in the inner diameter surface 2a of the outer ring 2, and the mounting groove 3b of the inner ring 3 is notched 3c formed in the outer diameter surface 3a of the inner ring 3. At the bottom. For this reason, the center part of the elastic member 4 located in the notches 2c and 3c is not in contact with the outer ring 2 and the inner ring 3, and the deformation of the elastic member 4 is not obstructed.

  The elastic member 4 may be any member that can be elastically deformed (has flexibility), and may be, for example, a leaf spring or rubber. Further, the circumferential thickness of the elastic member 4 and the circumferential widths of the mounting groove 2b of the outer ring 2 and the mounting groove 3b of the inner ring 3 depend on the torque that is expected to be input to the torque detection device 1. Set as appropriate.

  As shown in FIG. 1, the outer ring 2 has a collar-shaped shoulder 2d extending toward the inner diameter side at one end in the axial direction, and the side surface of the shoulder 2d (the end surface in the axial direction of the shoulder 2d) One end face 3e is in contact. A lid 5 is attached to the other end of the outer ring 2 in the axial direction, and the end surface 5a of the lid 5 presses the step surface 3f of the inner ring 3 in the axial direction so that the inner ring 3 does not come off in the axial direction. . The side surface of the shoulder portion 2d of the outer ring 2, the end surface 3e of the inner ring 3, the end surface 5a of the lid 5, and the step surface 3f of the inner ring 3 are respectively similar to the inner diameter surface 2a of the outer ring 2 and the outer diameter surface 3a of the inner ring 3. It is slidable.

  Each of the sliding surfaces may be coated with a sliding material having good sliding characteristics, such as a fluororesin. Further, instead of coating the sliding surface with the sliding material, a bearing (not shown) may be interposed between the surfaces of the outer ring 2 and the inner ring 3 that are rotationally displaced from each other.

  1 and 2, a magnetic sensor 6 is provided on the inner diameter surface 2 a of the outer ring 2. The magnetic sensor 6 is mounted on a substrate 7 fixed to the inner diameter surface 2 a of the outer ring 2. The magnetic sensor 6 has two detectors 6a and 6b (FIG. 1) arranged in the axial direction.

  A magnetic encoder 8 is provided in a recess 3d formed on the outer diameter surface 3a of the inner ring 3 so as to face the magnetic sensor 6 in the radial direction and extend in the circumferential direction. The magnetic encoder 8 has a first magnetic encoder track 8a (FIG. 1) and a second magnetic encoder track 8b (FIG. 1) arranged in the axial direction. The magnetic encoder 8 has an arc shape and is provided only in a part of the circumference. Since the outer ring 2 and the inner ring 3 are connected by an elastic member 4 and only slightly rotate with each other, there is no problem even if the range in which the angle of the magnetic encoder 8 can be detected is a part of the circumference.

  The magnetic field of the first magnetic encoder track 8a is detected by the detection unit 6a of the magnetic sensor 6, and the magnetic field of the second magnetic encoder track 8b is detected by the detection unit 6b of the magnetic sensor 6. As shown in FIG. 4, the magnetic sensor 6 and the magnetic encoder 8 constitute an angle detector 40a. Further, the angle detection unit 40a and the angle calculation means 50 of the processing circuit 1b constitute an angle sensor 40 that detects the rotation angle between the outer ring 2 and the inner ring 3.

  1 and 2, a key 9 is provided on the outer diameter surface of the inner ring 3, and a key groove 2 e having a wider width in the circumferential direction than the key 9 is formed on the inner diameter surface 2 a of the outer ring 2. . Thereby, the rotation range of the inner ring 3 with respect to the outer ring 2 is limited to the range of the difference between the circumferential width of the key groove 2 e and the circumferential width of the key 9.

  FIG. 3 shows the magnetization patterns of the magnetic encoder tracks 8a and 8b of the magnetic encoder 8 as seen from the III-III cross section of FIG. The first and second magnetic encoder tracks 8a and 8b are alternately magnetized with N and S poles, respectively. The number of magnetic poles of both magnetic encoder tracks 8a and 8b are different from each other. In the example of FIG. 3, the first magnetic encoder track 8a has a larger number of magnetic poles than the second magnetic encoder track 8b. For example, assuming that the magnetic encoder 8 exists in a range of 360 degrees, the number of magnetic poles of the first magnetic encoder track 8a is 32 pole pairs, and the number of magnetic poles of the second magnetic encoder track 8b is 31 pole pairs. It is said that.

  FIG. 4 is a block diagram showing the configuration of the angle sensor 40 angle calculation means 50. Magnetic signals (see FIGS. 5A and 5B) output from the detection units 6a and 6b of the magnetic sensor 6 are sent to the angle calculation means circuit 50. For example, as described above, when the number of magnetic poles per circumference is 32 pole pairs in the first magnetic encoder track 8a and 31 pole pairs in the second magnetic encoder track 8b, the magnetic sensor 6 and the magnetic encoder 8 are When relatively rotated, a phase difference corresponding to one magnetic pole pair per rotation (see FIG. 5C) occurs. This phase difference is detected by the phase difference detector 51, and the absolute angle calculator 52 calculates the absolute angle of the rotational displacement based on the phase difference. The obtained absolute angle information is sent to the torque calculation means 10 described later by the transmission unit 53. High-resolution absolute angle information can be obtained by electrically multiplying the magnetic signals output from the detectors 6a and 6b by a multiplier circuit (not shown).

  FIG. 6 is a block diagram of the torque calculation means 10. In the torque calculation means 10, the torque calculation unit 13 acts between the outer ring 2 and the inner ring 3 based on the absolute angle information sent from the angle sensor 40 and the information recorded in the correction table 12. Calculate the torque. The correction table 12 records the relationship between the rotation angle of the outer ring 2 and the inner ring 3 and the torque. The torque value calculated by the torque calculation unit 13 is output to the outside via the output unit 14. The output unit 14 outputs the torque value to the outside with an output specification selected from PWM output, serial communication, or the like.

For example, when the number of magnetic poles per circumference is 32 pole pairs in the first magnetic encoder track 8a and 31 pole pairs in the second magnetic encoder track 8b, the angular resolution of the magnetic sensor 6 is about 16 bits to 18 bits. can get. If tentatively 1 resolution per revolution 18 bits, the amount of change in the angular difference of the outer ring 2 and the inner ring 3 are once if any 728 pulses ^(218/360) is obtained. Since the output signal is a digital signal, the output offset is suppressed due to environmental changes.

  The torque detection device 1 has the above-described configuration and operates as follows. That is, when torque is applied between the outer ring 2 and the inner ring 3, the elastic member 4 connecting the outer ring 2 and the inner ring 3 is deformed, and rotational displacement occurs between the outer ring 2 and the inner ring 3. The angle of this rotational displacement is detected by the angle sensor 40, and the torque calculation means 10 calculates the torque from the detected value.

  That is, the torque detection device 1 detects the amount of bending of the elastic member 4 as an absolute angle change between the outer ring 2 and the inner ring 3, and converts the angle into torque. The relationship between the amount of change in angle between the outer ring 2 and the inner ring 3 and the torque varies depending on the rigidity of the elastic member 4. Although the amount of change in angle is generally minute, since the absolute angle can be detected with high resolution, it is possible to detect torque with high accuracy and little temperature drift.

  As described above, since the rotational displacement between the outer ring 2 and the inner ring 3 is directly detected by the angle sensor 40, there is no need to convert the displacement other than the rotation into the rotational displacement as in the case of obtaining the torque from the displacement other than the rotation. Yes, the processing circuit 1b can be simplified. Further, since a minute rotational displacement between the outer ring 2 and the inner ring 3 is measured and converted into torque, mechanical adjustment after mounting the angle sensor 40 is necessary. Furthermore, in the case of this embodiment, since the absolute angle between the outer ring 2 and the inner ring 3 is converted into torque, accurate torque can be obtained.

  In this embodiment, an example is shown in which an angle sensor capable of detecting an absolute angle of one rotation is used as the magnetic angle sensor 40, but a rotation angle range of 90 degrees or 180 degrees is detected by an absolute angle. Possible sensors may be used. For example, a resolver having a shaft angle multiplier of 2 or 4 (2X, 4X corresponds to this).

  FIG. 7 is a cross-sectional view taken along a plane passing through the axis of the mechanism of the torque detector according to a different embodiment of the present invention, and FIG. 8 is a cross-sectional view taken along the line VIII-VIII. The torque detector 15 is an axial type in which the magnetic encoder 8 faces the magnetic sensor 6 in the axial direction. FIG. 9 shows magnetization patterns of the magnetic encoder tracks 8a and 8b of the magnetic encoder 8 as seen from the IX-IX cross section of FIG. In the example shown in the figure, the magnetic encoder 8 is provided for one turn in the circumferential direction, but the magnetic encoder 8 is limited to only a necessary range in the circumferential direction as in the case of FIGS. It is good also as a sector shape. Other than that, it is the same structure as the torque detection apparatus 1 of FIG. 1, FIG. 2, and the same effect | action and effect as the torque detection apparatus 1 of FIG. 1, FIG. 2 are acquired.

  FIG. 10 is a cross-sectional view taken along a plane passing through the axial center of the mechanism portion of the torque detection device according to still another embodiment of the present invention, and FIG. The torque detector 16 includes a bearing 17 with an angle sensor as an angle detector.

  The bearing 17 with an angle sensor includes a bearing 23 and an angle sensor 40. The bearing 23 includes an inner ring 18 that is a rotating wheel, an outer ring 19 that is a fixed ring, a rolling element 20, a cage 21, and a seal 22. The angle sensor 40 includes the magnetic encoder 24, the magnetic sensor 6, and the angle calculation means 50 (FIG. 4).

  A magnetic encoder 24 that is a rotating element is attached to the outer diameter surface of the end portion of the inner ring 18. The magnetic encoder 24 includes a cored bar 25 and a double-row magnetic encoder track 26 having two rows of magnetic encoder tracks 26a and 26b. The two rows of magnetic encoder tracks 26a and 26b are alternately magnetized with N and S poles, respectively.

  One end of a metal ring 27 is fitted to the inner diameter surface of the end portion of the outer ring 19, and an annular sensor housing 28 made of resin is attached to the metal ring 27. A printed circuit board 29 on which the magnetic sensor 6 is mounted is attached inside the sensor housing 28. The magnetic sensor 6 is connected to the angle calculation means 50 (see FIG. 4), and the angle calculation means 50 is connected to the torque calculation means 10 (see FIG. 6). The angle calculation means 50 and the torque calculation means 10 may be provided in the sensor housing 28 or may be provided outside the bearing 17 with the angle sensor.

  The outer ring 19 of the bearing 23 is assembled in the inner diameter hole 30b in a state of being in contact with the shoulder portion 30a of the housing 30, and the bearing cover 31 is fastened to the housing 30 with a bolt (not shown). It is integrated. Further, the shaft 32 is press-fitted and fixed in the inner diameter hole 18 a of the inner ring 18, and the inner ring 18 and the shaft 32 are integrated.

  One end 32 a of the shaft 32 and the housing 30 are joined via a plurality of elastic members 4. Both ends of the elastic member 4 are fixed to an axial groove 32b provided on the outer diameter surface of the end portion of the shaft 32 and an axial groove 30c provided on the inner diameter surface of the end portion of the housing 30 by press-fitting or adhesive. Is done. One end of the elastic member 4 may be slidable along the axial groove 32b or 30c as long as it can restrain the rattling in the circumferential direction. By connecting the shaft 32 and the housing 30 via the elastic member 4 in this way, the inner ring 18 and the outer ring 19 of the bearing 23 are indirectly connected via the elastic member 4.

  When torque is applied to the shaft 32, the elastic member 4 is deformed and the shaft 32 rotates slightly. The angle is detected by the angle sensor 40, and the torque is detected by the torque calculation means 10 (see FIG. 6) converting the angle information into torque. If the output of the bearing 17 with the angle sensor is set to zero degrees while no load torque is applied and the elastic member 4 is not bent, offset correction at the time of torque conversion can be omitted.

  FIG. 12 is a sectional view taken along a plane passing through the axis of a torque detector according to still another embodiment of the present invention, and FIG. 13 is an XIII-XIII sectional view thereof. In the torque detection device 33, the housing 30 and the shaft 32 are connected using an elastic member unit 36. As shown in FIG. 13, the elastic member unit 36 includes an outer diameter ring 34 fixed to the end face of the housing 30 (FIG. 12), an inner diameter ring 35 fixed to the end portion of the shaft 32 (FIG. 12), It comprises a plurality of elastic members 4 that connect the outer diameter ring 34 and the inner diameter ring 35. The housing 30 and the outer diameter ring 34 are fixed, and the shaft 32 and the inner diameter ring 35 are fixed using a bolt (not shown) or the like. Other than this, the configuration is the same as that of the torque detection device 16 of FIGS.

  The torque detectors 1, 15, 16, 33 of the above embodiments detect the amount of bending of the elastic member 4 as an absolute angle change between the outer rings 2, 19 and the inner rings 3, 18, and convert the angle into torque. Even without the absolute angle detection function, the rotation angle can be grasped and the torque calculated by counting high-resolution pulse outputs (90-phase phase difference A-phase and B-phase outputs) with a counter (reversible counter). Is also possible.

  FIG. 14 shows an example of a magnetic encoder and a magnetic sensor that output a high-resolution pulse signal. The magnetic encoder 8 is formed with a single-row magnetic encoder track 8a in which N poles and S poles are alternately magnetized. The magnetic sensor 6 electrically multiplies the magnetic signal obtained from the N pole and the S pole, and outputs a high resolution pulse signal.

  As shown in FIG. 15, the angle detector 40 a including the magnetic encoder 8 and the magnetic sensor 6 constitutes the angle sensor 40 together with the angle calculation means 60. The angle detection means 60 electrically multiplies the magnetic signal sent from the magnetic sensor 6 by the multiplication circuit 61 to the angle of one pole pair of the N pole and the S pole of the magnetic encoder track 8a, and provides a high resolution pulse signal. Is generated. For example, if the width of one pole pair of N pole and S pole is 2.54 mm and the distance between the pole pairs is multiplied by 4096 divisions, a position signal with a high resolution of 0.625 μm per pulse can be obtained. The generated pulse signal is counted by the counter 37 to obtain angle information. In this case, the counter 37 may be reset in a state where no torque is applied. The angle information obtained here is converted into torque using the torque detection means 10 similar to that in FIG.

  As mentioned above, although the form for implementing this invention based on the Example was demonstrated, embodiment disclosed here is an illustration and restrictive at no points. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1,15,16,33 ... Torque detection apparatus 2, 19 ... Outer ring 3, 18 ... Inner ring 4 ... Elastic member 6 ... Magnetic sensor 6a, 6b ... Detection part 8 ... Magnetic encoder 8a, 8b ... Magnetic encoder track 10 ... Torque calculation Means 17 ... Bearing 40 with angle sensor ... Angle sensor 51 ... Phase difference detection unit 52 ... Absolute angle calculation unit 53 ... Transmission unit 61 ... Multiplication circuit 62 ... Counter

Claims (6)

A torque detecting device that has an outer ring and an inner ring that are rotatable relative to each other, and detects torque acting between the outer ring and the inner ring,
An elastic member that connects the outer ring and the inner ring directly or indirectly and deforms according to rotational displacement between the outer ring and the inner ring, an angle sensor that detects a rotation angle between the outer ring and the inner ring, and the angle sensor And a torque calculating means for calculating the torque from the detected value.   2. The torque detection device according to claim 1, wherein the angle sensor is provided on one of the outer ring and the inner ring, and a magnetic encoder in which magnetic poles are arranged in a circumferential direction, and one of the outer ring and the inner ring. And a magnetic sensor for detecting a magnetic field of the magnetic encoder. 3. The torque detector according to claim 2, wherein the magnetic encoder has at least one row of magnetic encoder tracks in which N and S poles are alternately magnetized.
The angle sensor is a high voltage obtained by electrically multiplying the angle of one pole pair of the N pole and the S pole of the magnetic encoder track from a magnetic signal output by the magnetic sensor due to a rotational displacement between the magnetic encoder and the magnetic sensor. A torque detector comprising: a multiplying circuit for generating a resolution pulse signal; and a counter for counting the pulse signals generated by the multiplying circuit and sending the counted angle information to the torque calculating means. 3. The torque detector according to claim 2, wherein the magnetic encoder has a double-row magnetic encoder track in which N poles and S poles are alternately magnetized with different numbers of magnetic pole pairs, and the magnetic sensor. Has a plurality of detectors for detecting the magnetic fields of the double-row magnetic encoder tracks,
The angle sensor includes: a phase difference detection unit that detects a phase difference between magnetic signals output from the plurality of detection units of the magnetic sensor according to rotational displacement between the magnetic encoder and the magnetic sensor; and the phase difference detection unit. A torque detection apparatus comprising: an absolute angle calculation unit that calculates an absolute angle of the rotational displacement based on the detected phase difference; and a transmission unit that sends absolute angle information of the absolute angle calculation unit to the torque calculation unit.   5. The torque detection device according to claim 3, wherein a range in which the angle of the magnetic encoder can be detected is a part of a circumference.   The torque detection device according to any one of claims 1 to 5, wherein the outer ring and the inner ring are an outer ring and an inner ring of a bearing, respectively, and the angle sensor is provided integrally with the bearing. A torque detection device that constitutes a bearing with an angle sensor together with the angle sensor.

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