JP6377335B2 - Data detection method and detection device in detection device - Google Patents

Description

  The present invention relates to a data detection method and a detection device in a detection device such as a rotary encoder.

In a rotary encoder that detects rotation of a rotating body with respect to a fixed body, for example, a magnet is provided on the rotating body side, and a magnetic sensor device (detection device) including a magnetoresistive element and a Hall element is provided on the fixed body side. Among such magnetic sensor devices, for example, in a magnetic sensor device including a magnetoresistive element, a magnetoresistive film is formed on one surface of a substrate, and two phases (A phase and B phase) constituted by the magnetoresistive film are formed. Based on the two outputs output from the bridge circuit, the angular velocity, the angular position, and the like of the rotating body are detected (for example, see Patent Document 1).

  That is, as shown in FIG. 7, since the A-phase output indicates a SIN wave and the B-phase output indicates a COS wave, the arc tangent can be obtained from the A-phase data and the B-phase data obtained at a predetermined timing. For example, the angular position of the magnet with respect to the magnetic sensor device can be obtained.

JP 2012-118000 A

  In the above rotary encoder, high reliability is required for both the A-phase data and the B-phase data. For this reason, as schematically shown in FIG. 7, a plurality of timings are set at regular intervals within the data detection period T, and A obtained at odd-numbered timings (time t1, t3, t5). Oversampling is used in which the arc tangent is obtained using the arithmetic average of the phase data and the arithmetic average of the B phase data obtained at the even-numbered timing (time t2, t4, t6).

  However, in the oversampling shown in FIG. 7, the arithmetic average of the A phase data corresponds to the data at the time t3, whereas the arithmetic average of the B phase data corresponds to the data at the time t4. There is a time lag between the arithmetic mean of the phase data and the arithmetic mean of the B phase data. Therefore, when the arc tangent is obtained from the A phase data and the B phase data, there is a problem that the angular position of the magnet with respect to the magnetic sensor device cannot be obtained with high accuracy.

  In view of the above problems, an object of the present invention is to provide a detection method and a detection device in a detection device that can increase the simultaneity of data from two detection units even when oversampling is employed. is there.

In order to solve the above-described problem, a data detection method in a detection device according to the present invention obtains first data from a first detection unit within a data detection period in which a plurality of timings are set every predetermined time. And a data acquisition step of obtaining second data from the second detection unit, a first detection value in the data detection period is determined based on the first data, and within the data detection period based on the second data A detection value determining step for determining a second detection value in the step, wherein the sum of the number of acquisition times of the first data and the number of acquisition times of the second data within the data detection period is five times in the data acquisition step. The data detection period is set continuously in the odd number of times as described above, and in the current data detection period, the first timing is the odd number of times among the plurality of times. Give chromatography data give the second data at even-numbered timing, the next of said data detection period, among said plural timings, to obtain a first data even-numbered timing, at odd-numbered timing The second data is obtained.

The detection device according to the present invention includes a first detection unit, a second detection unit, and a first data from the first detection unit within a data detection period in which a plurality of timings are set every predetermined time. A data acquisition unit for obtaining second data from the second detection unit , a first detection value in the data detection period based on the first data, and the data based on the second data A detection value determining unit that determines a second detection value within a detection period, wherein the data acquisition unit includes a sum of the number of acquisitions of the first data and the number of acquisitions of the second data within the data detection period. Is set to an odd number of times of 5 or more, and the data detection period is set continuously. In the current data detection period, the first data is stored at an odd number of times among the plurality of times. To obtain the second data at even-numbered timing, the next of said data detection period, among said plural timings, to obtain a first data even-numbered timing, the second data at odd-numbered timing It is characterized by obtaining.

  In the present invention, since the sum of the number of acquisition times of the first data and the number of acquisition times of the second data within the data detection period is 3 times or more, at least one of the first data and the second data has a plurality of times. Acquired oversampling is performed. For this reason, the reliability of data can be improved. In addition, since the sum of the number of times of acquisition of the first data and the number of times of acquisition of the second data within the data detection period is an odd number of 3 or more, the detection value is calculated using the average of the data acquired at the odd-numbered timing. In the case where the detection value is determined using the average of the data acquired at the even-numbered timing, the detection value corresponds to the central time of the data detection period. Therefore, even when oversampling is employed, the simultaneity of data from the two detection units can be increased.

Further, the sum of the number of acquisition times of the first data and the number of acquisition times of the second data within the data detection period is 5 times or more . For this reason, since oversampling is performed on both the first data and the second data, the reliability of the data can be improved. Further, in the data detection period of this time, the first data is obtained at an odd number of times, the second data is obtained at an even number of times, and the first data is obtained at an even number of times in the next data detection period, The second data is obtained at an odd number of times. For this reason, the data acquisition at the odd number is one more than the data acquisition at the even number, but since the data acquisition at the odd number and the data acquisition at the even number are interchanged, the number of acquisitions of the first data And the number of acquired second data can be made equal.

In the present invention, the first detector continuously outputs the first analog data, the second detector continuously outputs the second analog data, and the first analog data and the second analog data are output. A / D converter that alternately converts digital data into digital data, and in the data acquisition step, the A / D converter converts the first analog data into digital data as the first data , A configuration may be employed in which the second data is a result of converting the second analog data into digital data. According to this configuration, oversampling can be realized by one A / D converter, and the simultaneity of data from the two detection units is high.

  In the present invention, in the detection value determination step, for example, the first detection value is determined by an arithmetic average of the first data, and the second detection value is determined by an arithmetic average of the second data.

  In the present invention, in the detection value determination step, the first data is added to calculate the first detection value, the second data is added to calculate the second detection value, and the first data is calculated. At least one of the calculation of the detection value and the calculation of the second detection value performs weighted addition by multiplying the center of the data detection period by a symmetric coefficient on the front side and the rear side, thereby obtaining the first detection value. It is preferable that the bit length matches the bit length of the second detection value. In this case, as the coefficient, it is preferable to perform weighted addition by multiplying data obtained at a time close to the center of the data detection period by a larger coefficient than data obtained at a time far from the center of the data detection period. . According to such a configuration, the first detection value and the second detection value can be determined without using division. Therefore, the data processing load can be reduced, and the processing speed can be increased. In addition, since the bit length of the first detection value and the bit length of the second detection value are matched by performing weighted addition, an operation using the first detection value and the second detection value can be easily performed. Can do.

  In this case, the coefficient is preferably a power of 2. According to such a configuration, since bit shift is sufficient, it is not necessary to perform multiplication. Therefore, the data processing load can be reduced, and the processing speed can be increased.

  In the present invention, for example, the first detector is a first magnetoresistive film of a magnetoresistive element, the second detector is a second magnetoresistive film of the magnetoresistive element, and the first magnetoresistive film. Outputs the first analog data consisting of a SIN wave based on the magnetic field change from the magnet rotating relative to the magnetoresistive element, and the second magnetoresistive film is based on the magnetic field change from the magnet. Output the second analog data comprising COS waves, and after the detection value determining step, the angle of the magnet with respect to the magnetoresistive element based on the first detection value and an arctangent corresponding to the second detection value A configuration for calculating the position can be employed.

  In the present invention, the plurality of timings are set for each time obtained by dividing the data detection period by the sum of the number of acquisitions of the first data and the number of acquisitions of the second data within the data detection period. It is preferable. According to this configuration, the number of data acquisitions within the data detection period can be maximized.

  In the present invention, since the sum of the number of acquisition times of the first data and the number of acquisition times of the second data within the data detection period is 3 times or more, at least one of the first data and the second data has a plurality of times. Acquired oversampling is performed. For this reason, the reliability of data can be improved. In addition, since the sum of the number of times of acquisition of the first data and the number of times of acquisition of the second data within the data detection period is an odd number of 3 or more, the detection value is calculated using the average of the data acquired at the odd-numbered timing. In the case where the detection value is determined using the average of the data acquired at the even-numbered timing, the detection value corresponds to the central time of the data detection period. Therefore, even when oversampling is employed, the simultaneity of data from the two detection units can be increased.

It is explanatory drawing of the rotary encoder to which this invention is applied. It is explanatory drawing of the electrical connection structure of the magnetoresistive film | membrane of the magnetoresistive element used for the rotary encoder to which this invention is applied. It is explanatory drawing which shows the principle of the rotary encoder to which this invention is applied. It is a flowchart which shows the data detection method implemented with the rotary encoder to which this invention is applied. It is explanatory drawing which shows typically the content of the oversampling implemented with the rotary encoder to which this invention is applied. It is explanatory drawing which shows the effect which implemented oversampling in the rotary encoder to which this invention is applied. It is explanatory drawing which shows the content of the oversampling which concerns on a reference example typically.

  Hereinafter, a rotary encoder will be mainly described as a detection device to which the present invention is applied with reference to the drawings. In the rotary encoder, when detecting the rotation of the rotating body relative to the fixed body, the fixed body is provided with a magnet, the rotating body is provided with a magnetoresistive element, and the fixed body is provided with a magnetoresistive element. Any of the configurations in which the magnet is provided may be adopted. However, in the following description, the description will focus on the configuration in which the magnetic sensor device is provided in the fixed body and the magnet is provided in the rotating body.

[Schematic configuration of rotary encoder]
FIG. 1 is an explanatory diagram of a rotary encoder 1 to which the present invention is applied. FIG. 2 is an explanatory diagram of an electrical connection structure of the magnetoresistive films 41 to 44 of the magnetoresistive element 4 used in the rotary encoder 1 to which the present invention is applied. FIG. 3 is an explanatory diagram showing the principle of the rotary encoder 1 to which the present invention is applied. FIGS. 3 (a) and 3 (b) are explanatory diagrams of signals output from the magnetoresistive element 4, and the signals and It is explanatory drawing which shows the relationship with the angular position (electrical angle) of the rotary body.

  A rotary encoder 1 shown in FIG. 1 is a device that magnetically detects rotation around an axis (rotation axis) of a rotating body 2 with respect to a fixed body (not shown) by a magnetic sensor device 10, and the fixed body is a motor. The rotating body 2 is fixed to a frame or the like of the device, and is used in a state of being connected to a rotation output shaft or the like of the motor device. On the side of the rotating body 2, a magnet 20 is held that directs the magnetized surface 21 in which the N pole and the S pole are magnetized one by one in the circumferential direction to one side in the rotation axis direction L. It rotates around the rotation axis integrally with the rotating body 2.

  On the fixed body side, there is a magnetic sensor device 10 including the magnetoresistive element 4 facing the magnetized surface 21 of the magnet 20 on one side in the rotation axis direction L, a control unit 90 that performs processing to be described later, and the like. Is provided. In addition, the magnetic sensor device 10 includes a first hall element 61 and a second hall element 62 located at a position that is shifted by 90 ° in the circumferential direction with respect to the first hall element 61 at a position facing the magnet 20. And.

  The magnetoresistive element 4 includes a substrate 40 and a two-phase magnetoresistive film having a phase difference of 90 ° with respect to the phase of the magnet 20 (A-phase (SIN) magnetoresistive film (first detection unit 4a), and And a B-phase (COS) magnetoresistive film (second detection unit 4b). In the magnetoresistive element 4, the first detector 4 a (A phase magnetoresistive film) detects + A phase (SIN +) magnetoresistive film 43 (first magnetic resistance film) that detects the movement of the rotating body 2 with a phase difference of 180 °. Resistance film) and a -A phase (SIN-) magnetoresistive film 41 (first magnetoresistive film), and the second detector 4b (B phase magnetoresistive film) has a phase difference of 180 °. A + B phase (COS +) magnetoresistive film 44 (second magnetoresistive film) and a −B phase (COS−) magnetoresistive film 42 (second magnetoresistive film) for detecting the movement of the rotating body 2 are provided. . The magnetoresistive films 41 to 44 of the magnetoresistive element 4 having such a configuration rotate in such a manner that the direction changes in the in-plane direction of the magnetized surface 21 with a magnetic field strength equal to or higher than the saturation sensitivity region of the resistance value of each of the magnetoresistive films 41 to 44. Detect magnetic field.

  In the first detection unit 4a, the + A-phase magnetoresistive film 43 and the -A-phase magnetoresistive film 41 constitute a bridge circuit shown in FIG. 2A, and one end thereof is the A-phase power supply terminal VccA. The other end is connected to the ground terminal GNDA for A phase. An output terminal + A from which the + A phase is output is provided at the midpoint position of the + A phase magnetoresistive film 43, and an output from which the −A phase is output at the midpoint position of the −A phase magnetoresistive film 41. Terminal -A is provided. In the second detection unit 4b, the + B-phase magnetoresistive film 44 and the -B-phase magnetoresistive film 42 are similar to the + A-phase magnetoresistive film 44 and the -A-phase magnetoresistive film 41 in FIG. ), One end is connected to the B-phase power supply terminal VccB, and the other end is connected to the B-phase ground terminal GNDB. An output terminal + B from which the + B phase is output is provided at the midpoint position of the + B phase magnetoresistive film 44, and an output from which the −B phase is output at the midpoint position of the −B phase magnetoresistive film 42. Terminal -B is provided. In FIG. 2, for convenience, the A-phase power supply terminal VccA and the B-phase power supply terminal VccB are shown, but the A-phase power supply terminal VccA and the B-phase power supply terminal VccB are common. May be. For convenience, FIG. 2 shows the A-phase ground terminal GNDA and the B-phase ground terminal GNDB, but the A-phase ground terminal GNDA and the B-phase ground terminal GNDB are common. May be.

  In the magnetic sensor device 10 and the rotary encoder 1 of this embodiment, the first detection unit 4a and the second detection unit 4b of the magnetoresistive element 4 are output from the amplification circuits 91a and 91b and the amplification circuits 91a and 91b. An A / D converter 93 that converts first analog data SIN and second analog data COS into first data DSIN and second data DCOS obtained by digital conversion, and a CPU that performs various arithmetic processes on the first data DSIN and second data DCOS A control unit 90 including an (arithmetic circuit) and the like is configured. The first Hall element 61 and the second Hall element 62 are provided with amplifier circuits 92a and 92b and an A / D converter 94.

In the rotary encoder 1 having such a configuration, as shown in FIG. 3A, when the rotating body 2 makes one revolution, the magnet 20 also makes one revolution. Therefore, from the magnetoresistive element 4, the first analog data SIN and the second Analog data COS is output for two cycles. Therefore, after the first analog data SIN and the second analog data COS are amplified by the amplifier circuits 91a and 91b, the A / D converter 93 converts the first data DSIN and the second data DCOS into digital data, and the control unit 90 When output, the Lissajous diagram shown in FIG. 3B can be obtained. Further, if the arc tangent (θ = TAN ⁻¹ (SIN / COS)) is obtained from the first data DSIN and the second data DCOS, the angular position θ of the rotation output shaft can be obtained. In the present embodiment, the first Hall element 61 and the second Hall element 62 are arranged at a position shifted by 90 ° from the center of the magnet 20. For this reason, depending on the combination of the outputs of the first Hall element 61 and the second Hall element 62, the current position is output in two periods of the first analog data SIN and the second analog data COS. You can see where it is located. Accordingly, the rotary encoder 1 generates absolute angular position information of the rotating body 2 based on the detection result of the magnetoresistive element 4, the detection result of the first Hall element 61, and the detection result of the second Hall element 62. The absolute operation can be performed.

(Data detection)
FIG. 4 is a flowchart showing a data detection method implemented by the rotary encoder 1 to which the present invention is applied. FIG. 5 is an explanatory diagram schematically showing the contents of oversampling performed by the rotary encoder 1 to which the present invention is applied.

  In the rotary encoder 1 of the present embodiment, when obtaining the first data DSIN and the second data DCOS, oversampling described below is performed for the purpose of improving data reliability. Further, for the purpose of enhancing the simultaneity of the first data DSIN and the second data DCOS, the timing for acquiring the first data DSIN and the second data DCOS is set as follows.

In order to realize such a method, in the rotary encoder 1 of the present embodiment, as shown in FIG. 1, the A / D converter 93 obtains the first data DSIN from the first analog data SIN, and from the second analog data COS. A timing control unit 95 that controls the timing of obtaining the second data DCOS is provided. The control unit 90 also includes a first detection value determination unit 97a (detection value determination unit) that determines the first detection value ESIN in the current data detection period based on the plurality of first data DSIN obtained by oversampling. And a second detection value determination unit 97b (detection value determination unit) that determines the second detection value ECOS within the current data detection period based on the second data DCOS. Further, the control unit 90 uses the first detection value ESIN and the second detection value ECOS to calculate an arc tangent (θ = TAN ⁻¹ (ESIN / ECOS)) in the current data detection period; The current data detection period of the rotating body 2 based on the calculation result of the arc tangent (θ = TAN ⁻¹ (ESIN / ECOS)), the detection result of the first Hall element 61, and the detection result of the second Hall element 62 And a position determining unit 96 for determining the absolute angle position at. Here, the timing control unit 95 may employ either a configuration provided inside the control unit 90 or a configuration provided outside the control unit 90, but in this embodiment, the timing control unit 95 It is provided inside the control unit 90. The timing control unit 95 sets conditions based on a command from the external command unit 99. The control unit 90 is composed of a microcomputer, and performs processing described with reference to FIGS. 4 and 5 based on a program stored in advance in a memory (not shown).

(Data acquisition step S10)
In this embodiment, as shown in FIG. 4, in the rotary encoder 1, when the data detection period T is reached by the first control pulse P1 (see FIG. 5), the following data acquisition step S10 starts. First, in step S1, the total number N of data acquisitions is set based on the content previously instructed from the external command unit 99, and in step S2, the variable n is set to 1. The total number N of data acquisition is set as an odd number of 3 or more, preferably an odd number of 5 or more. In this embodiment, for simplification of description, it is assumed that the total number N of data acquisition is set to 5. For this reason, in the present embodiment, the first data DSIN from the first detector 4a is generated at a total of five times at regular intervals based on the control pulse P2 (see FIG. 5) in one data detection period T. And acquisition of the second data DCOS from the second detection unit 4b.

  Next, in step S3, it is determined whether the variable n is an odd number. In this determination, when it is determined that the variable n is an odd number (time t1 in FIG. 5), in step S4, the A / D converter 93 determines from the first analog data SIN output from the first detection unit 4a. First data DSIN (first first data DSIN1) is acquired. In step S5, 1 is added to the variable n (n = 2), and in step S7, it is determined whether the variable n is N. If it is determined in step S7 that the variable n is not N, the process returns to step S3.

  Next, in step S3, it is determined whether the variable n is an odd number. In this determination, when it is determined that the variable n is not an odd number (time t2 in FIG. 5), in step S6, the A / D converter 93 starts from the second analog data COS output from the second detection unit 4b. Two data DCOS (first second data DCOS1) is acquired. Then, after adding 1 to the variable n in step S5, it is determined whether or not the variable n is N in step S7. If it is determined in step S7 that the variable n is not N, the process returns to step S3.

  Next, when it is determined in step S3 that the variable n is an odd number (time t3 in FIG. 5), the A / D converter 93 is output from the first detection unit 4a in step S4. The first data DSIN (second first data DSIN2) is obtained from the first analog data SIN. In step S5, after adding 1 to the variable n (n = 3), it is determined in step S7 whether the variable n is N or not. If it is determined in step S7 that the variable n is not N, the process returns to step S3.

  Next, when it is determined in step S3 that the variable n is not an odd number (time t4 in FIG. 5), in step S6, the A / D converter 93 outputs the second output from the second detection unit 4b. The second data DCOS (second second data DCOS2) is acquired from the two analog data COS. In step S5, 1 is added to the variable n (n = 4), and in step S7, it is determined whether the variable n is N. If it is determined in step S7 that the variable n is not N, the process returns to step S3.

  Next, when it is determined in step S3 that the variable n is an odd number (time t5 in FIG. 5), in step S4, the A / D converter 93 is output from the first detection unit 4a. First data DSIN (third first data DSIN3) is obtained from the first analog data SIN. In step S5, 1 is added to the variable n (n = 5), and in step S7, it is determined whether the variable n is N.

(Detection value determination process)
If it is determined in step S7 that the variable n is N, a detection value determining step is performed in step S8. In the detection value determination step, the first detection value determination unit 97a shown in FIG. 1 calculates the first detection value ESIN in the current data detection period T based on the first data DSIN (first data DSIN1, DSIN2, DSIN3). The second detection value determination unit 97b shown in FIG. 1 determines the second detection value ECOS based on the second data DCOS (second data DCOS1, DCOS2). For example, the first detection value determination unit 97a determines the arithmetic average of the first data DSIN1, DSIN2, and DSIN3 as the first detection value ESIN in the current data detection period T, and the second detection value determination unit 97b The arithmetic average of the two data DCOS1 and DCOS2 is determined as the second detection value ECOS in the current data detection period T.

(Calculation process)
Next, in step S9, an arctangent (θ = TAN ⁻¹ (ESIN / ECOS)) in the current data detection period is obtained using the first detection value ESIN and the second detection value ECOS. As a result, the position determination unit 96 shown in FIG. 1 calculates the arc tangent (θ = TAN ⁻¹ (ESIN / ECOS)), the detection result in the first Hall element 61, and the detection in the second Hall element 62. Based on the result, the absolute angular position of the rotating body 2 in the current data detection period T is determined. Then, the variable n is set to 0, the total number N of data acquisition is initialized to 0, and the current data detection period T ends.

  Thereafter, when the next data detection period T is reached by the first control pulse P1 (see FIG. 5), the same operation is repeated.

(Main effects of this form)
FIG. 6 is an explanatory diagram showing the effect of oversampling in the rotary encoder 1 to which the present invention is applied.

  As described above, in the rotary encoder 1 of the present embodiment, since the sum of the number of acquisition times of the first data DSIN and the number of acquisition times of the second data DCOS within the data detection period T is three times or more, the first data DSIN and At least one of the second data DCOS is oversampled to acquire a plurality of times. For this reason, the reliability of data can be improved. In particular, in this embodiment, since the sum of the number of acquisition times of the first data DSIN and the second data DCOS within the data detection period T is 5 times or more, both the first data DSIN and the second data DCOS are multiple times. Oversampling is performed to obtain the data. For this reason, the reliability of data can be improved. For example, when the first data DSIN and the second data DCOS are acquired in a state where the magnet 20 is stopped, when the oversampling is not performed, the data variation is large as shown in FIG. When the sum of the number of acquisition times of one data DSIN and the number of acquisition times of the second data DCOS is 5 or more, the data variation is small.

  In this embodiment, since the sum of the number of acquisition times of the first data DSIN and the number of acquisition times of the second data DCOS is an odd number of 3 or more, the arithmetic average of the first data DSIN acquired at the odd-numbered timing is calculated. When the first detection value ESIN is determined using the arithmetic mean of the second data acquired at the even-numbered timing, the first detection value ESIN and the second detection value ECOS are determined. Corresponds to the time t3 at the center of the data detection period T. Therefore, even when oversampling is employed, the simultaneity of the first detection value ESIN and the second detection value ECOS can be increased.

  In this embodiment, the plurality of times are set for each time obtained by dividing the data detection period by the sum of the number of acquisitions of the first data DSIN and the number of acquisitions of the second data DCOS within the data detection period T. . For this reason, the number of data acquisitions within the data detection period T can be maximized.

(Example of improved detection value determination method)
In the above embodiment, in the detection value determination step, the first detection value ESIN and the second detection value ECOS are determined using the arithmetic mean, but the first detection value ESIN is calculated by adding the first data DSIN. The second detection value ECOS may be calculated by adding the second data DCOS . In this case, at least one of the calculation of the first detection value ESIN and the calculation of the second detection value ECOS is performed by performing weighted addition by multiplying the center of the data detection period T by a coefficient symmetric on the front side and the rear side, The bit length of the first detection value ESIN is matched with the bit length of the second detection value ECOS. Further, as a coefficient, a first addition is performed by multiplying data obtained at a time close to the center of the data detection period T by a larger coefficient than data obtained at a time far from the center of the data detection period T. The bit length of the detection value is matched with the bit length of the second detection value.

  According to such a configuration, the first detection value ESIN and the second detection value ECOS can be determined without using division. Therefore, the data processing load can be reduced, and the processing speed can be increased. Further, in order to make the bit length of the first detection value ESIN and the bit length of the second detection value ECOS coincide by performing weighted addition, an operation using the first detection value ESIN and the second detection value ECOS is performed. It can be done easily.

  At that time, the power is a power of 2. According to such a configuration, since bit shift is sufficient, it is not necessary to perform multiplication. Therefore, the data processing load can be reduced, and the processing speed can be increased.

  For example, when the first detection value ESIN is calculated by adding the first data DSIN, a value obtained by adding a value obtained by multiplying the following coefficients is set as the first detection value ESIN.

Coefficient (2 ⁰ ) x first data DSIN1
Coefficient (2 ¹ ) x 1st data DSIN2
Coefficient (2 ⁰ ) x 1st data DSIN3
On the other hand, when the second data DCOS is added to calculate the second detection value ECOS, a value obtained by adding a value obtained by multiplying the following coefficients is set as the second detection value ECOS.

Coefficient (2 ¹ ) x 2nd data DCOS1
Coefficient (2 ¹ ) x 2nd data DCOS2
When the sum of the number of acquisition times of the first data DSIN and the number of acquisition times of the second data DCOS is nine times, a total of five first data DSIN1 to DSIN5 and a total of four second data DCOS1 to COS4 are obtained. The coefficient may be set as in the following conditions 1, 2, and 3 to determine the first detection value ESIN and the second detection value ECOS.

Condition 1
First detection value ESIN
Coefficient (2 ⁰ ) x first data DSIN1
Coefficient (2 ¹ ) x 1st data DSIN2
Coefficient (2 ¹ ) x 1st data DSIN3
Coefficient (2 ¹ ) x 1st data DSIN4
Coefficient (2 ⁰ ) x 1st data DSIN5
Second detection value ECOS
Coefficient (2 ¹ ) x 2nd data DCOS1
Coefficient (2 ¹ ) x 2nd data DCOS2
Coefficient (2 ¹ ) x 2nd data DCOS3
Coefficient (2 ¹ ) x 2nd data DCOS4
Condition 2
First detection value ESIN
Coefficient (2 ⁰ ) x first data DSIN1
Coefficient (2 ⁰ ) x first data DSIN2
Coefficient (2 ¹ ) x 1st data DSIN3
Coefficient (2 ⁰ ) x 1st data DSIN4
Coefficient (2 ⁰ ) x 1st data DSIN5
Second detection value ECOS
Coefficient (2 ⁰ ) x second data DCOS1
Coefficient (2 ¹ ) x 2nd data DCOS2
Coefficient (2 ¹ ) x 2nd data DCOS3
Coefficient (2 ⁰ ) x 2nd data DCOS4
Condition 3
First detection value ESIN
Coefficient (2 ⁰ ) x first data DSIN1
Coefficient (2 ⁰ ) x first data DSIN2
Coefficient (2 ¹ ) x 1st data DSIN3
Coefficient (2 ⁰ ) x 1st data DSIN4
Coefficient (2 ⁰ ) x 1st data DSIN5
Second detection value ECOS
Coefficient (2 ¹ ) x 2nd data DCOS1
Coefficient (2 ⁰ ) x second data DCOS2
Coefficient (2 ⁰ ) x second data DCOS3
Coefficient (2 ¹ ) x 2nd data DCOS4

(Other embodiments)
The conditions in the timing control unit 95 are switched from the external command unit 99 or the like shown in FIG. 1, and in the current data detection period T, the first data DSIN is obtained at an odd number of times among a plurality of times, and the even number of times. In the next data detection period T, the second data DCOS may be obtained at an odd-numbered timing and the first data DSIN may be obtained at an even-numbered time. The odd number of times of data acquisition is one more than the even number of times of data acquisition. However, according to this configuration, the odd number of times of data acquisition and the even number of times of data acquisition are interchanged. The number of acquisitions of DSIN and the number of acquisitions of the second data DCOS can be made equal.

(Other examples of detection device)
In the above embodiment, the rotary encoder 1 has been exemplified. However, in the detection apparatus having two detection units, the present invention may be applied to other sensor apparatuses and the like as long as the apparatus alternately acquires data. .

DESCRIPTION OF SYMBOLS 1 ... Rotary encoder 2 Rotating body 4 Magnetoresistive element 4a First detector 4b Second detector 41, 43 Magnetoresistive film (first magnetoresistive film)
42, 44 .. Magnetoresistive film (second magnetoresistive film)
90 ·· Control unit 93 · · A / D converter 95 · · Timing control unit 96 · · Position determination unit 98 · · Calculation unit SIN · · first analog data COS · · second analog data DSIN · · first data DCOS・ ・ Second data ESIN ・ ・ First detection value ECOS ・ ・ Second detection value

Claims (9)

A data acquisition step of obtaining first data from the first detection unit and obtaining second data from the second detection unit within a data detection period in which a plurality of timings are set every predetermined time;
A detection value determining step of determining a first detection value in the data detection period based on the first data and determining a second detection value in the data detection period based on the second data;
Have
In the data acquisition step, the sum of the number of acquisitions of the first data and the number of acquisitions of the second data within the data detection period is an odd number of 5 or more,
The data detection period is set continuously,
In the data detection period this time, the first data is obtained at an odd-numbered timing among the plurality of timings, and the second data is obtained at an even-numbered timing ,
In the next said data detection period, among said plural timings, to obtain a first data even-numbered timing, the data detection method in the detection apparatus characterized by obtaining said second data at odd-numbered timing . The first detector continuously outputs the first analog data, and the second detector continuously outputs the second analog data,
An A / D converter that alternately converts the first analog data and the second analog data into digital data is provided,
In the data acquisition step, a result of converting the first analog data into digital data by the A / D converter is used as the first data, and a result of converting the second analog data into digital data is used as the second data. The data detection method in the detection apparatus of Claim 1 characterized by the above-mentioned.   2. The detection value determining step, wherein the first detection value is determined by an arithmetic average of the first data, and the second detection value is determined by an arithmetic average of the second data. Or a data detection method in the detection device according to 2; In the detection value determining step, the first data is added to calculate the first detection value, the second data is added to calculate the second detection value,
At least one of the calculation of the first detection value and the calculation of the second detection value is performed by performing a weighted addition by multiplying a center of the data detection period by a symmetric coefficient on the front side and the rear side. The data detection method in the detection device according to claim 1, wherein a bit length of a detection value is matched with a bit length of the second detection value.   The weighted addition obtained by multiplying data obtained at a time close to the center of the data detection period by a larger coefficient than data obtained at a time far from the center of the data detection period is performed as the coefficient. Item 5. A data detection method in the detection device according to Item 4.   The data detection method in the detection apparatus according to claim 4, wherein the coefficient is a power of two. The first detector is a first magnetoresistive film of a magnetoresistive element;
The second detection unit is a second magnetoresistive film of the magnetoresistive element;
The first magnetoresistive film outputs the first analog data including a SIN wave based on a magnetic field change from a magnet that rotates relative to the magnetoresistive element,
The second magnetoresistive film outputs the second analog data composed of COS waves based on a magnetic field change from the magnet,
3. The angular position of the magnet with respect to the magnetoresistive element is calculated after the detection value determining step based on an arc tangent corresponding to the first detection value and the second detection value. Data detection method in the detection apparatus.   The plurality of times are set for each time obtained by dividing the data detection period by the sum of the number of acquisitions of the first data and the number of acquisitions of the second data within the data detection period. The data detection method in the detection apparatus as described in any one of Claim 1 thru | or 7. A first detection unit;
A second detection unit;
A data acquisition unit that obtains first data from the first detection unit and obtains second data from the second detection unit within a data detection period in which a plurality of timings are set every predetermined time; and
A detection value determining unit that determines a first detection value in the data detection period based on the first data and determines a second detection value in the data detection period based on the second data;
Have
In the data acquisition unit, a sum of the number of acquisition times of the first data and the number of acquisition times of the second data within the data detection period is set to an odd number of times of 5 or more,
The data detection period is set continuously,
In the data detection period this time, the first data is obtained at an odd-numbered timing among the plurality of timings, and the second data is obtained at an even-numbered timing ,
In the next said data detection period, said among the plural timings, to obtain a first data even-numbered timing detecting device characterized by obtaining said second data at odd-numbered timing.

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