JP5925485B2 - Encoder device and signal generation method for encoder device - Google Patents

Description

  The present invention relates to an encoder device for detecting a rotation angle of a rotating body. The present invention also relates to a signal generation method of an encoder device for detecting a rotation angle of a rotating body.

  Conventionally, a magnetic encoder device for detecting a rotation angle of a rotating body is known (see, for example, Patent Document 1). The magnetic encoder device described in Patent Document 1 is provided in an AC servo motor, and is a disk-shaped magnetic recording medium fixed to the rotating shaft of the motor and a magnetic recording formed on the outer peripheral surface of the magnetic recording medium. And a magnetic sensor arranged to face the surface. The magnetic sensor includes an MR element, and a signal processing unit including a waveform shaping circuit and a multiplier circuit is connected to an output terminal of the MR element.

JP-A-9-218053

  In recent years, a user-friendly encoder device is required in the encoder device market. Accordingly, an object of the present invention is to provide an encoder device capable of improving usability. It is another object of the present invention to provide a signal generation method for an encoder device that can improve the usability of the encoder device.

  In order to solve the above problems, an encoder apparatus according to the present invention includes an encoder that outputs a position data signal for detecting a rotation angle of a rotating body, and difference value data that is a difference value of position data at a predetermined cycle. A difference value data generation unit to generate, a frequency division multiplication unit to generate frequency division multiplication data obtained by dividing or multiplying the difference value data, and an A phase signal, a B phase signal, and a Z phase signal based on the frequency division multiplication data A signal output unit that outputs, and a setting data generation unit that generates setting data for setting the number of one rotation division in the signal output unit that determines the timing at which the signal output unit outputs the Z-phase signal. When the integer is 1 or more, the frequency division / multiplication unit generates frequency division / multiplication data by dividing or multiplying the difference value data by the frequency division / multiplication ratio N / M, and the signal output unit sets the setting data therein. And frequency division When the accumulated value of the data reaches the number of divisions per rotation, the Z-phase signal is output and the accumulated value of the frequency division multiplied data is reset. As a product of the number of pulses to be output and the frequency division multiplication ratio N / M, and is an integer multiple of 4.

  In the encoder device of the present invention, the frequency division / multiplication unit generates frequency division / multiplication data obtained by dividing or multiplying the difference value data by the frequency division / multiplication ratio N / M, and the setting data generation unit is configured such that the signal output unit has a Z phase. Generates setting data for setting in the signal output unit the number of one-rotation divisions that determines the signal output timing. The signal output unit sets the setting data therein, and the accumulated value of the divided multiplication data is When the number of divisions per rotation is reached, the Z-phase signal is output and the accumulated value of the frequency division multiplied data is reset. In the encoder device according to the present invention, the number of divisions per rotation is a product of the number of pulses output as a position data signal by the encoder during one rotation of the rotating body and the frequency division ratio N / M, and It is an integer multiple of 4. Therefore, in the present invention, if the number of rotations per rotation set in the signal output unit is an integer multiple of 4, the number of rotations per rotation is converted into a position data signal by the encoder while the rotor rotates once. It is possible to set an arbitrary value according to the number of pulses to be output and the frequency division / multiplication ratio N / M. Therefore, according to the present invention, it is possible to improve the usability of the encoder device.

  In the present invention, the encoder device includes a microprocessor (Micro-Processing Unit (MPU)) having a difference value data generation unit, a frequency division multiplication unit, and a setting data generation unit, and the signal output unit includes a programmable logic device (Programmable). It is preferable that the microprocessor communicates with a programmable logic device using an SPI (Serial Peripheral Interface). If comprised in this way, it will become possible to reduce the number of the signal lines between a microprocessor and a programmable logic device, and to simplify the structure of an encoder apparatus.

  In the present invention, the transmission data sent from the microprocessor to the programmable logic device preferably includes a switching bit for switching the content of the transmission data. If comprised in this way, it will become possible to shorten the data length of the transmission data transmitted from a microprocessor to a programmable logic device, and to raise the communication speed from a microprocessor to a programmable logic device.

  In order to solve the above problem, the signal generation method of the encoder device according to the present invention is based on position data from an encoder that outputs a position data signal for detecting a rotation angle of a rotating body. , A signal generation method for an encoder device that generates a B-phase signal and a Z-phase signal, where M and N are integers equal to or greater than 1, and generates difference value data that is a difference value of position data in a predetermined cycle; Generates frequency-division multiplication data obtained by dividing or multiplying the difference value data by the frequency division multiplication ratio N / M, generates an A-phase signal and a B-phase signal based on the frequency-division multiplication data, and When the accumulated value reaches the one-rotation division number that determines the timing for outputting the Z-phase signal, the Z-phase signal is generated and the accumulated value of the frequency-division multiplication data is reset. Enko There is the product of the number and the division multiplication ratio N / M of the output pulse as a signal of the position data, and is characterized in that an integral multiple of 4.

  In the signal generation method of the encoder device according to the present invention, the difference value data that is the difference value of the position data is generated at a predetermined cycle, and the frequency division multiplied data obtained by dividing or multiplying the difference value data by the frequency division multiplication ratio N / M. And the accumulated value of the divided multiplied data is reset while the Z-phase signal is generated and the accumulated value of the divided multiplied data is reset. In the present invention, the number of divisions per rotation is the product of the number of pulses output as a position data signal by the encoder during one rotation of the rotating body and the frequency division multiplication ratio N / M, and 4 It is an integer multiple. Therefore, in the signal generation method of the present invention, if the number of divisions per revolution is an integral multiple of 4, this number of divisions per revolution is output by the encoder as a position data signal while the rotating body makes one revolution. It is possible to set an arbitrary value in accordance with the number of sigma and the frequency division multiplication ratio N / M. Therefore, if the signal generation method of the present invention is used, the usability of the encoder device can be improved.

  As described above, according to the present invention, it is possible to improve the usability of the encoder device. Further, if the signal generation method for an encoder apparatus according to the present invention is used, the usability of the encoder apparatus can be improved.

It is a block diagram for demonstrating schematic structure of the encoder apparatus concerning embodiment of this invention. It is the schematic for demonstrating schematic structure of the encoder shown in FIG. It is a figure for demonstrating an example of the communication format of the transmission data sent to the signal output part from the signal processing part shown in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Configuration of encoder device)
FIG. 1 is a block diagram for explaining a schematic configuration of an encoder apparatus 1 according to an embodiment of the present invention. FIG. 2 is a schematic diagram for explaining a schematic configuration of the encoder 2 shown in FIG. FIG. 3 is a diagram for explaining an example of a communication format of transmission data sent from the signal processing unit 3 to the signal output unit 4 shown in FIG.

  The encoder device 1 of the present embodiment is a device for detecting the rotation angle (rotation position) of a rotating body, and specifically, for example, a device for detecting the rotation angle of a rotor of a servo motor. As shown in FIG. 1, the encoder device 1 includes an encoder 2, a signal processing unit 3 that processes a signal output from the encoder 2, and an A phase signal, B based on a signal output from the signal processing unit 3. And a signal output unit 4 for outputting a phase signal and a Z-phase signal. The signal processing unit 3 is connected to the output side of the encoder 2, and the signal output unit 4 is connected to the output side of the signal processing unit 3. The output side of the signal output unit 4 is connected to a higher-level control unit that controls the servo motor.

  The encoder 2 is an absolute encoder (absolute value encoder). Further, the encoder 2 of this embodiment is a magnetic encoder, and as shown in FIG. 2, a sensor magnet 8 fixed to a rotating shaft 7 constituting a rotor of a servo motor and a sensor magnet 8 are arranged opposite to each other. The magnetoresistive element 9 and the Hall element 10 are provided.

  The sensor magnet 8 is a permanent magnet formed in a disk shape. On the surface of the sensor magnet 8 facing the magnetoresistive element 9 and the Hall element 10, one N pole and one S pole are formed in the circumferential direction. The magnetoresistive element 9 is arranged so that the center of the sensor magnet 8 and the center of the magnetoresistive element 9 substantially coincide when viewed from the axial direction of the rotating shaft 7. The magnetoresistive element 9 is formed with a magnetoresistive pattern arranged in a direction substantially orthogonal to each other. The hall elements 10 are arranged at positions shifted from each other by 90 ° with respect to the center of the sensor magnet 8 when viewed from the axial direction of the rotary shaft 7.

  The magnetoresistive element 9 is connected to a CPU (Central Processing Unit) 12 through a pair of amplifier circuits 11. The hall element 10 is connected to the CPU 12 via the amplifier circuit 13. An output interface (not shown) is connected to the CPU 12.

  The encoder 2 outputs a position data signal indicating a rotation angle within a range of one rotation (360 °) of the rotating body (rotor) to the signal processing unit 3 based on the detection result of the magnetoresistive element 9. . The resolution of the encoder 2 of this embodiment is 12 bits or 14 bits. When the resolution of the encoder 2 is 12 bits, the number of pulses output as a position data signal by the encoder 2 during one rotation of the rotating body is 4096, and the resolution of the encoder 2 is 14 bits. The number of pulses that the encoder 2 outputs as a position data signal during one rotation of the rotating body is 16384.

  The encoder 2 outputs a multi-rotation data signal indicating how many times the rotating body has rotated from a predetermined origin position to the signal processing unit 3 based on the detection result of the Hall element 10. Furthermore, the encoder 2 outputs a signal indicating an error state of the encoder 2 toward the signal processing unit 3. The encoder 2 communicates with the signal processing unit 3 through an SPI (Serial Peripheral Interface). The encoder 2 communicates with the signal processing unit 3 at a constant communication cycle. That is, the signal processing unit 3 acquires position data, multi-rotation data, and the like at a constant cycle.

  The signal processing unit 3 is a microprocessor (MPU). The signal processing unit 3 includes an encoder input interface unit 16, a position data processing unit 17, a frequency division multiplication unit 18, a setting data generation unit 19, and an encoder output interface unit 20 as functions thereof. The encoder input interface unit 16 is connected to the output side of the encoder 2, the position data processing unit 17 is connected to the output side of the encoder input interface unit 16, and the frequency division multiplication unit 18 is connected to the output side of the position data processing unit 17. It is connected to the. The encoder output interface unit 20 is connected to the output side of the frequency division / multiplication unit 18 and the output side of the setting data generation unit 19. The output side of the encoder output interface unit 20 is connected to the input side of the signal output unit 4.

  The position data processing unit 17 generates difference value data that is a difference value of position data input from the encoder 2 via the encoder input interface unit 16 at a constant cycle. In the present embodiment, difference value data that is a difference value between position data acquired every communication cycle between the encoder 2 and the signal processing unit 3 and position data acquired last time is generated. The position data processing unit 17 of the present embodiment is a difference value data generation unit that generates difference value data that is a difference value of position data at a predetermined cycle.

  The frequency division / multiplication unit 18 generates frequency division / multiplication data obtained by dividing or multiplying the difference value data output from the position data processing unit 17. Specifically, when M and N are integers equal to or greater than 1, the frequency division / multiplication unit 18 generates frequency division / multiplication data obtained by dividing or multiplying the difference value data by the frequency division / multiplication ratio N / M.

  The setting data generation unit 19 determines the timing at which the signal output unit 4 outputs the Z-phase signal. The number of one-rotation division (that is, the number of pulses (edges) of the A-phase signal during one rotation of the rotating body Setting data for setting the signal output unit 4 to the sum of the number of pulses (edges). The number of divisions per rotation is the product of the number of pulses output as a position data signal by the encoder 2 and the division / multiplication ratio N / M during one rotation of the rotating body. Here, the division multiplication ratio N / M is set so that the number of divisions per rotation is an integral multiple of four. The phase of the A phase signal and the phase of the B phase signal are shifted by 90 °, and one period of the A phase signal or the B phase signal corresponds to 4 pulses, so that the number of divisions per rotation is an integral multiple of 4. This is because it is necessary to set the division / multiplication ratio N / M.

  The signal processing unit 3 outputs the divided multiplication data toward the signal output unit 4. Further, the signal processing unit 3 outputs setting data for setting the number of rotation divisions to the signal output unit 4 toward the signal output unit 4. Further, the signal processing unit 3 outputs reset data for resetting the accumulated value of the frequency-division multiplied data in the signal output unit 4, and outputs of the A phase signal, the B phase signal, and the Z phase signal from the signal output unit 4. Output permission data for permission is output toward the signal output unit 4.

  The communication format of transmission data sent from the signal processing unit 3 to the signal output unit 4 is set as shown in FIG. 3, for example. In this embodiment, the word length of the transmission data is 11 bits. The most significant bit (first bit) SR10 of the transmission data is a switching bit for switching whether the signal processing unit 3 transmits the frequency division multiplied data or the setting data. That is, the transmission data includes a switching bit for switching the content of the transmission data.

  When the frequency division multiplied data is transmitted (when the first bit SR10 = 0), the second bit SR9 is accumulated in the signal output unit 4 as shown in FIG. 3A. This is a bit for reset data for resetting the value, and when the accumulated value of the frequency division multiplied data in the signal output unit 4 is not reset, the second bit SR9 becomes “0”, and the signal output unit 4 When resetting the accumulated value of the frequency-division multiplied data, the second bit SR9 is “1”. The third bit SR8 is a bit for output permission data for permitting the output of the A phase signal, the B phase signal and the Z phase signal from the signal output unit 4, and the A phase signal from the signal output unit 4 When the output of the B phase signal and the Z phase signal is permitted, the third bit SR8 becomes “0”, and the output of the A phase signal, the B phase signal and the Z phase signal from the signal output unit 4 is not permitted. In this case, the third bit SR8 is “1”.

  Further, when the frequency division multiplied data is transmitted, the fourth bit SR7 is a bit for determining the plus / minus of the frequency division multiplied data, and the rotating body is rotating in the positive direction, and the frequency division multiplication is performed. When the data is positive, the fourth bit SR7 is “0”, the rotating body is rotating in the reverse direction, and when the frequency-division multiplication data is negative, the fourth bit SR7 is “1”. It becomes. Further, the fifth bit SR6 to the eleventh bit SR0 are bits for frequency division multiplied data.

  Further, when setting data for setting the number of rotations per rotation to the signal output unit 4 is transmitted (when the first bit SR10 = 1), the word length of the number of rotations per rotation in this embodiment is 16 bits. In this case, as shown in FIG. 3B, the second bit SR9 is a bit for selecting a set digit for the number of rotation divisions. When the lower 8 bits of the 16 bits are set, the second bit SR9 is “0”, and when the upper 8 bits are set, the second bit SR9 is “1”. Also, the fourth bit SR7 to the eleventh bit SR0 are bits for setting the number of rotation divisions. When setting data is transmitted, the third bit SR4 is not used.

  The signal processing unit 3 communicates with the signal output unit 4 by SPI. The signal processing unit 3 communicates with the signal output unit 4 at a constant communication cycle. Specifically, communication is performed at the same communication cycle as the communication cycle between the encoder 2 and the signal processing unit 3.

  The signal output unit 4 is a programmable logic device. Specifically, the signal output unit 4 of the present embodiment is a complex programmable logic device (CPLD). The signal output unit 4 is mounted on the same circuit board on which the signal processing unit 3 is mounted. The signal output unit 4 may be a field programmable gate array (FPGA).

  The signal output unit 4 sets the setting data output from the signal processing unit 3 therein. That is, the signal output unit 4 sets the number of rotation divisions to the value input from the signal processing unit 3. Further, the signal output unit 4 generates and outputs an A-phase signal and a B-phase signal based on the frequency division multiplied data. In addition, when the accumulated value of the divided multiplied data reaches the number of one rotation division, the signal output unit 4 generates and outputs a Z-phase signal and resets (clears) the accumulated value of the divided multiplied data.

  In the encoder apparatus 1 configured as described above, the signal processing unit 3 sets the frequency division / multiplication ratio N / M and sets the number of rotation divisions to the signal output unit 4 at the initial operation such as when the power is turned on. Setting data to be generated is output to the signal output unit 4. The signal output unit 4 sets the setting data output from the signal processing unit 3 therein. Further, the signal processing unit 3 sets an initial position of the rotating body.

  Further, during normal operation of the encoder apparatus 1, the signal processing unit 3 generates difference value data, generates frequency division multiplied data, and outputs the generated frequency division multiplied data to the signal output unit 4. The signal output unit 4 outputs an A-phase signal and a B-phase signal based on the frequency-division multiplication data, and outputs a Z-phase signal and frequency division when the accumulated value of the frequency-division multiplication data reaches the number of divisions per rotation. Reset the accumulated value of multiplication data.

(Main effects of this form)
As described above, in this embodiment, the one-rotation division number that determines the timing at which the signal output unit 4 outputs the Z-phase signal is the number of pulses that the encoder 2 outputs as a position data signal while the rotor rotates once. It is the product of the number and the frequency division / multiplication ratio N / M. In the present embodiment, the setting data generation unit 19 generates setting data for setting the number of rotation divisions in the signal output unit 4, and the signal output unit 4 sets this setting data internally. Therefore, in this embodiment, if the number of one-rotation divisions set in the signal output unit 4 is an integer multiple of four, this one-rotation division number is calculated by the encoder 2 while the rotating body makes one rotation. It is possible to set an arbitrary value according to the number of pulses output as a signal and the frequency division / multiplication ratio N / M. For example, the number of rotation divisions can be set to 10,000 or 360. Therefore, in this embodiment, the usability of the encoder device 1 can be improved.

  In this embodiment, the signal processing unit 3 communicates with the signal output unit 4 by SPI. Therefore, in this embodiment, the number of signal lines between the signal processing unit 3 and the signal output unit 4 can be reduced, and the configuration of the encoder device 1 can be simplified. In this embodiment, the transmission data sent from the signal processing unit 3 to the signal output unit 4 includes a switching bit (specifically, the first bit SR10) for switching the content of the transmission data. It is possible to shorten the data length of transmission data sent from the signal processing unit 3 to the signal output unit 4 and increase the communication speed from the signal processing unit 3 to the signal output unit 4.

(Other embodiments)
The above-described embodiment is an example of a preferred embodiment of the present invention, but is not limited to this, and various modifications can be made without departing from the scope of the present invention.

  In the above-described form, the signal output unit 4 is a CPLD and is an electronic component different from the signal processing unit 3 that is an MPU. In addition, for example, the signal output unit 4 may constitute a part of the signal processing unit 3. That is, the signal processing unit 3 may have the function of the signal output unit 4 to output the A phase signal, the B phase signal, and the Z phase signal from the signal processing unit 3.

  In the embodiment described above, the signal processing unit 3 communicates with the signal output unit 4 through SPI, but the signal processing unit 3 may communicate with the signal output unit 4 through parallel communication. In the above-described form, the transmission data sent from the signal processing unit 3 to the signal output unit 4 includes a switching bit. For example, the signal processing unit 3 communicates with the signal output unit 4 in parallel communication. Alternatively, the transmission data may have a longer word length so that the transmission data does not include a switching bit.

  In the embodiment described above, the encoder 2 is an absolute encoder, but the encoder 2 may be an incremental encoder. In the above-described embodiment, the encoder 2 is a magnetic encoder. The encoder 2 is, for example, a slit plate in which a light emitting element and a light receiving element, and a slit that transmits light from the light emitting element to the light receiving element are formed. May be a photoelectric encoder. Further, the encoder 2 may be an encoder other than a magnetic type or a photoelectric type.

DESCRIPTION OF SYMBOLS 1 Encoder apparatus 2 Encoder 3 Signal processing part (microprocessor)
4 signal output part (programmable logic device)
17 Position data processing unit (difference value data generation unit)
18 Divider / Multiplier 19 Setting data generator SR10 Switching bit

Claims (4)

An encoder that outputs a position data signal for detecting the rotation angle of the rotating body, a difference value data generation unit that generates difference value data that is a difference value of the position data in a predetermined cycle, and the difference value data A frequency division / multiplication unit that generates frequency division / multiplication frequency division data, a signal output unit that outputs an A phase signal, a B phase signal, and a Z phase signal based on the frequency division multiplication data, and the signal output unit, A setting data generation unit that generates setting data for setting the number of one rotation division for determining the timing of outputting the Z-phase signal in the signal output unit;
When M and N are integers of 1 or more,
The frequency division / multiplication unit generates the frequency division / multiplication data obtained by dividing or multiplying the difference value data by a frequency division / multiplication ratio N / M,
The signal output unit sets the setting data therein and outputs the Z-phase signal and accumulates the divided multiplied data when the accumulated value of the divided multiplied data reaches the one rotation division number. Reset the value,
The one-rotation division number is a product of the number of pulses output by the encoder as the position data signal and the division / multiplication ratio N / M during one rotation of the rotating body, and an integer of 4 An encoder device characterized by being doubled. A microprocessor (Micro-Processing Unit (MPU)) having the difference value data generation unit, the frequency division multiplication unit, and the setting data generation unit;
The signal output unit is a programmable logic device (Programmable Logic Device (PLD)),
The encoder apparatus according to claim 1, wherein the microprocessor communicates with the programmable logic device by an SPI (Serial Peripheral Interface).   The encoder apparatus according to claim 2, wherein the transmission data sent from the microprocessor to the programmable logic device includes a switching bit for switching the content of the transmission data. A signal generation method for an encoder apparatus that generates an A-phase signal, a B-phase signal, and a Z-phase signal based on the position data from an encoder that outputs a position data signal for detecting a rotation angle of a rotating body. ,
When M and N are integers of 1 or more,
Generating difference value data that is a difference value of the position data in a predetermined cycle;
Generate frequency division / multiplication data obtained by dividing or multiplying the difference value data by a frequency division / multiplication ratio N / M,
When the A-phase signal and the B-phase signal are generated based on the frequency-division multiplied data, and the accumulated value of the frequency-division multiplied data reaches the number of one rotation division that determines the timing for outputting the Z-phase signal, Generating a Z-phase signal and resetting the accumulated value of the frequency division multiplied data;
The one-rotation division number is a product of the number of pulses output by the encoder as the position data signal and the division / multiplication ratio N / M during one rotation of the rotating body, and an integer of 4 A method for generating a signal of an encoder device, wherein the signal is doubled.

Images