JP2016063735A - Control unit of stepping motor, electronic apparatus, storage unit, robot, control method of stepping motor and control program of stepping motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control unit capable of easily calculating detection electric angle signal to reduce limitations relevant to the resolution of an encoder.SOLUTION: A control unit 1 includes: a position generation section 30 that generates a position signal Pn which includes a piece of position information of a rotor; an electric angle detection section 40 that outputs a detected electric angle signal φ which includes a piece of information of an electric angle obtained by multiplying a coefficient to the position signal Pn; and a drive section 20 that outputs an excitation current to a coil based on an amplitude signal Id including the amplitude information of the excitation current and the detected electric angle signal φ.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a stepping motor control device, an electronic device, a recording device, a robot, a stepping motor control method, and a stepping motor control program.

The stepping motor is a synchronous motor that rotates a rotor by magnetic flux generated by supplying each exciting current to a plurality of phase coils provided in a stator. Since the rotation angle of the rotor is determined according to the number of input pulses, the stepping motor is easy to perform positioning control and is often driven by open loop control.
However, during high-speed driving or overload driving, the target position of the rotor and the actual position may deviate and step out.
Therefore, in the stepping motor, feedback control based on the position of the rotor may be executed in order to prevent step-out. Patent Document 1 discloses a technique for detecting the position of a rotor using an encoder and executing feedback control.

JP 2014-96922 A

By the way, in the conventional control device, the detection resolution of the encoder is set to N times the number of periods of the electrical angle per rotation of the rotor (N is a natural number of 2 or more), and the position of the rotor detected by the encoder is set to N The electrical angle of the rotor was detected based on the remainder divided by. For this reason, there is a problem that it is necessary to execute a remainder calculation, and further, the detection resolution of the encoder is restricted by the number of cycles of the electrical angle per rotation of the rotor.
The present invention has been made in view of the above-described circumstances, and it is an object to solve the problem that the electrical angle of the rotor can be calculated with a simple calculation and the resolution limitation of the encoder is relaxed.

  In order to solve the above-described problems, a control device for a stepping motor according to an aspect of the present invention includes a stepping motor that rotates a rotor by magnetic flux generated by supplying an excitation current to a coil corresponding to each of a plurality of phases. An electrical angle detection signal including a position generation unit that generates a position signal including the detected position information of the rotor, and electrical angle information obtained by multiplying the position signal by a coefficient. And an actuator for outputting the excitation current toward the coil based on the amplitude signal including the amplitude information of the excitation current and the detection signal of the electrical angle.

  According to this aspect, since the electrical signal is generated by multiplying the position signal by the coefficient, it is not necessary to calculate the remainder by the remainder calculation, and the calculation load can be reduced. In addition, since the resolution of the position generation unit is not restricted, the degree of freedom can be expanded.

  In one aspect of the stepping motor control device described above, the driving unit is based on the speed detection unit that outputs a speed detection signal including speed information of the rotor based on the position signal, and the speed detection signal. An advance angle generation unit for generating an advance angle signal including the advance angle information, and an electrical angle command including the electrical angle information of the excitation current based on the advance angle signal and the electrical angle detection signal. And a command unit that generates a signal, and outputs the excitation current based on the amplitude signal and the electrical angle command signal.

  According to this aspect, since the electrical angle command signal is generated based on the advance angle signal and the electrical angle detection signal, it is possible to efficiently generate torque according to the detection speed. Further, since there is no restriction on the resolution of the position generator, the advance angle accuracy can be improved and the control performance of the stepping motor can be improved by using the high-resolution position generator.

  In one aspect of the stepping motor control device described above, a deviation between a signal indicating a target value of a target position of the rotor and the position signal is calculated as a position error signal, and the position error signal is calculated based on the position error signal. A speed command signal including rotor speed information is generated, a deviation between the speed command signal and the speed detection signal is calculated as a speed error signal, and the amplitude signal is calculated based on the speed error signal. Is provided. According to this aspect, since the speed detection unit for generating the advance angle and the speed detection unit for feedback-controlling the detection speed can be used together, the configuration can be simplified.

  In one aspect of the above-described stepping motor control device, the position generator preferably has a resolution of 18 bits or more. According to this aspect, the performance of feedback control can be improved. As a result, compared to the coreless motor, which is the mainstream of industrial galvano motors, it is possible to use a stepping motor that is simple in structure and inexpensive in various devices.

In one aspect of the control device for the stepping motor described above, the coefficient is K, the electrical angle period per rotation of the rotor is α, the electrical angle control resolution is β, and the resolution of the position generation unit is γ. The coefficient K is given by the following equation:
K = (α × β / γ) × (β-1)
Is preferably given by:
In this case, since the cycle number α, the electrical angle control resolution β, and the position generation unit resolution γ are fixed, the coefficient K is also fixed, and the calculation is simplified.

  Next, an electronic device according to one embodiment of the present invention includes the above-described stepping motor control device and a stepping motor. Such electronic devices include laser scanner devices, NC processing machines, 3D printers, and the like.

  Next, a recording apparatus according to an aspect of the present invention includes the above-described stepping motor control device and a stepping motor. Such a recording apparatus (image printing apparatus) corresponds to a printer, a label printing apparatus, or the like.

  Next, a robot according to an aspect of the present invention includes the above-described stepping motor control device and a stepping motor. Examples of such robots include vertical articulated robots, double-arm robots, and other multi-axis robots.

  The above-described stepping motor control device can be grasped as a stepping motor control method. This control method is a stepping motor control method for controlling a stepping motor that rotates a rotor by a magnetic flux generated by supplying an exciting current to a coil corresponding to each of a plurality of phases, and indicates the position of the rotor. Obtaining a position signal, generating an electrical angle detection signal including electrical angle information obtained by multiplying the position signal by a coefficient, and based on the amplitude signal indicating the current amplitude and the electrical angle detection signal The excitation current is output.

  The above-described stepping motor control device can be grasped as a stepping motor control program. This control program controls a stepping motor that rotates a rotor by magnetic flux generated by supplying an excitation current to coils corresponding to each of a plurality of phases, and a coefficient is added to a position signal indicating the position of the rotor. An electrical angle detection signal including electrical angle information obtained by multiplying the electrical angle, and an electrical signal indicating the electrical angle of the excitation current based on the amplitude signal indicating the current amplitude and the electrical angle detection signal. A corner command signal is generated.

The figure which shows one structural example of the control apparatus of the stepping motor which concerns on embodiment of this invention. Explanatory drawing for demonstrating A phase current command signal and B phase current command signal. The figure which shows the structural example of the laser scanner apparatus to which the control apparatus of the stepping motor which concerns on embodiment of this invention is applied. 1 is an external perspective view of a vertical articulated (6-axis) robot to which a stepping motor control device according to an embodiment of the present invention is applied. 1 is a front view schematically showing a configuration example 1 (image recording apparatus) of a recording apparatus to which a control device for a stepping motor according to an embodiment of the present invention is applied. FIG. 6 is a front view schematically showing a configuration example 2 (printer) of a recording apparatus to which a stepping motor control device according to an embodiment of the invention is applied.

<Embodiment>
Hereinafter, a stepping motor control device (hereinafter, simply referred to as “control device”) and a control method according to an embodiment of the present invention will be described. FIG. 1 is a diagram illustrating a configuration example of a control device according to the present embodiment.
As shown in the figure, the control device 1 according to this embodiment is a device that controls the driving of the stepping motor M. A stepping motor unit is configured by integrating the control device 1 and the stepping motor M shown in FIG.

The stepping motor M includes an A-phase stator coil (hereinafter simply referred to as “A-phase coil”), a B-phase stator coil (hereinafter simply referred to as “B-phase coil”), a rotor to which a rotating shaft is attached, Is provided.
The stepping motor M is a so-called brushless motor. That is, a predetermined excitation current is supplied to the A phase coil and the B phase coil to generate a magnetic force, and the rotor is rotated by the magnetic force.
Specifically, in the stepping motor M, the phase to be excited is switched by switching the coil through which the excitation current flows, and the rotor is rotated.

  In this embodiment, a two-phase stepping motor M composed of an A phase and a B phase is used. However, the configuration of the stepping motor M is not limited to this. For example, the number of phases of the stepping motor M is not limited to two phases, and may be single phase, three phases, four phases, five phases, or the like. Also, the type of rotor is not particularly limited, and a PM (Permanent Magnet) type, a VR (Variable Reluctance) type, an HB (Hybrid) type, or the like can be used.

The control device 1 includes a processing unit 10, a drive unit 20, a position generation unit 30, and an electrical angle detection unit 40. The position generator 30 outputs a detected position signal (position signal) Pn including actual rotor position information. More specifically, the detected position signal Pn indicates the angle of the rotor as position information. The position generation unit 30 in this example includes an encoder 31 and a position detection unit 32. For example, the encoder 31 preferably has a resolution of 18 bits or more per rotation. When the resolution is 18 bits, the encoder 31 outputs 2 ¹⁸ −1 pulses per revolution. The position detector 32 counts the pulses output from the encoder 31 and generates a detected position signal Pn. Detected position signal Pn is ^{0, 1, 2,} ... 2 18 -1, 0, 1, ... As ^such, cycling through values of ^{0 to 2} 18 -1. The resolution of the position detector 32 is determined by the encoder 31. In this example, the encoder 31 and the position detection unit 32 are separated from each other, but it goes without saying that an encoder incorporating the position detection unit therein may be used.

Next, the processing unit 10 includes a position command unit 11, subtracters 12 and 14, a position control unit 13, and a speed control unit 15. Signal) Id is generated.
The position command unit 11 outputs a signal indicating a target value of the rotor position as a position command signal Pc. The position command signal Pc indicates the target rotor angle. The subtracter 12 receives the position command signal Pc from the position command unit 11 and feeds back the detected position signal Pn. The subtractor 12 calculates a deviation between the position command signal Pc and the detected position signal Pn (in other words, a value obtained by subtracting the detected position from the target value of the rotation angle of the rotor), and outputs a position error signal Pe indicating the calculation result. To do.
The position control unit 13 calculates a target value of the angular velocity of the stepping motor M according to the position error signal Pe by performing a predetermined calculation process using a proportional gain or the like on the position error signal Pe, and calculates the target value. Is output as a speed command signal (speed command signal) Vd.

  A speed command signal Vd is input from the position controller 13 to the subtracter 14 and a detected speed signal Vn indicating the current angular speed of the rotor is fed back. The subtractor 14 calculates a deviation between the speed command signal Vd and the detected speed signal Vn (in other words, a value obtained by subtracting the detected speed Vn from the target value of the angular speed of the rotor), and a speed error signal Ve (speed error signal). Output as. The speed control unit 15 uses the speed error signal Ve input from the subtractor 14 and a predetermined coefficient such as an angular velocity proportional gain, an angular velocity integral gain, and the like, and performs predetermined calculation processing including integration to thereby excite the excitation. A signal indicating the current amplitude is generated and output as a current amplitude command signal Id.

Next, the drive unit 20 includes a speed detection unit 21, an advance angle generation unit 22, and an electrical angle command unit (command unit) 23. Based on the detected position signal Pn indicating the current angle of the rotor, the speed detector 21 generates a detected speed signal (speed detection signal) Vn indicating the current angular speed (speed information) of the rotor, the subtractor 14 and the advance angle. Output to the generator 22. Since the speed detection unit for generating the advance angle and the speed detection unit for feedback-controlling the detection speed can be used together, the configuration is simplified.
The advance angle generation unit 22 generates an advance angle signal (advance angle signal including advance angle information) degree indicating an advance angle according to the detected speed signal Vn. When the angular velocity of the rotor is increased, the rotor is advanced before the torque is generated after the current flows through the coil, so that the time during which the torque can be generated is shortened. Therefore, it is possible to generate a large torque by advancing the timing of flowing a current through the coil according to the current angular velocity of the rotor. The advance angle is specified from the above viewpoint. More specifically, the advance angle generation unit 22 may include a table that associates the detected speed with the advance angle, and may generate the advance angle by referring to the table using the detected speed signal Vn. .

The electrical angle command unit 23 generates the electrical angle command signal θ based on the detected electrical angle signal (electrical angle detection signal) φ including the current electrical angle information and the advance angle signal degree. The detected electrical angle signal φ is generated by multiplying the detected position signal Pn by a coefficient K in the electrical angle detector 40. Here, when the number of electrical angle periods per rotation of the rotor is α, the control resolution of the electrical angle is β, and the detection resolution of the encoder is γ, the coefficient K is given by Equation 1 and the detected electrical angle signal (electrical Angle) φ is given by Equation 2.
K = (α × β / γ) × (β−1) Equation 1
φ = K × Pn Equation 2

For example, the electrical angle period α per rotation of the rotor is 50, the electrical angle control resolution β is 2 ⁸ (8 bits), the encoder detection resolution γ is 2 ²⁰ (20 bits), and the detection position signal Pn Assume that the detection position shown is 3000. In this case, the detected electrical angle signal φ is calculated by Equation 3.
^{φ = 3000 × (50 × 2} 8/2 20) × (2 8 -1) ... Equation 3

In the conventional control device, the detection resolution γ of the encoder is set to a natural number N times the cycle number α, and the detected electrical angle signal φ is calculated based on the remainder R obtained by dividing the detection position indicated by the detection position signal Pn by N. It was calculated. This method has a disadvantage in that it is necessary to perform a remainder operation and that the detection resolution γ of the encoder is limited by the number of periods α.
On the other hand, according to the present embodiment described above, the number of periods α, the electrical angle control resolution β, and the encoder detection resolution γ, which are elements of the coefficient K, are all known. Therefore, the coefficient K can be calculated and stored in advance, and the detected electrical angle signal φ can be calculated only by multiplication. Moreover, there is an advantage that the detection resolution γ of the encoder can be determined regardless of the cycle number α.

Next, when exciting the electrical angle 90 degrees ahead, the electrical angle command unit 23 sets the rotational direction CW when the rotor rotates in the forward direction to “1” and the rotational direction CW when the rotor rotates in the reverse direction. Is “−1”, the electrical angle command signal θ is calculated according to the following equations 4 and 5.
When CW = 1 θ = φ + degree + 90 ... Equation 4
In case of CW = −1 θ = φ + degree−90 Equation 5
Thus, since the electrical angle command signal θ is generated based on the advance angle signal degree and the detected electrical angle signal φ, it is possible to efficiently generate torque according to the detected speed signal Vn. Further, since the resolution of the position generation unit 30 is not restricted, the accuracy of the advance angle signal degree can be improved by using the high-resolution position generation unit 30, and the control performance of the stepping motor M can be improved. it can.

Furthermore, the drive unit 20 includes an A-phase current command unit 24, a B-phase current command unit 25, an A-phase drive unit 26, and a B-phase drive unit 27.
The A-phase current command unit 24 generates an A-phase current command signal Ida indicating the magnitude of the A-phase excitation current Ia to be applied to the A-phase coil based on the current amplitude command signal Id and the electrical angle command signal θ. The B-phase current command unit 25 generates a B-phase current command signal Idb indicating the magnitude of the B-phase excitation current Ib to be applied to the B-phase coil based on the current amplitude command signal Id and the electrical angle command signal θ.
More specifically, as shown in FIG. 2, the A-phase current command signal Ida is given by Equation 6 and the B-phase current command signal Idb is given by Equation 7.
Ida = Id × sin θ: Formula 6
Idb = Id × cos θ (Formula 7)

  The A-phase drive unit 26 shown in FIG. 1 generates an A-phase excitation current Ia so as to have the magnitude indicated by the A-phase current command signal Ida, and supplies it to the A-phase coil of the stepping motor M. The B-phase drive unit 27 generates a B-phase excitation current Ib so as to have the magnitude indicated by the B-phase current command signal Idb, and supplies it to the B-phase coil of the stepping motor M. The A-phase drive unit 26 may detect the magnitude of the A-phase excitation current Ia and perform feedback control so that the detected value approaches the A-phase current command signal Ida. This also applies to the B-phase drive unit 27.

  As described above, according to the control device 1 according to the present embodiment, the high-resolution encoder 31 can be freely used regardless of the cycle number α, and compared with the coreless motor that is the mainstream of industrial galvano motors. Thus, a simple and inexpensive stepping motor can be used for various devices.

<Electronic equipment>
<Laser scanner device>
Next, a laser scanner device as an example of an electronic apparatus to which the control device 1 and the stepping motor M described above are applied will be described. FIG. 3 is a diagram illustrating a configuration example of the laser scanner device 7 to which the stepping motor control device 1 and the stepping motor M according to the above-described embodiment are applied. The laser scanner device 7 can be used for cutting out printed materials such as labels. In the description of the laser scanner device 7, the above-described stepping motor M will be described as stepping motors 3A, 3B, 3C.
The laser scanner device 7 as an electronic device controls the laser oscillator 401, the first lens 403, the second lens 405, the first mirror 407, the second mirror 409, the stepping motor 3A, and the stepping motor 3A. A control device 1A, a control device 1B that controls the stepping motor 3B and the stepping motor 3B, and a control device 1C that controls the stepping motor 3C and the stepping motor 3C are provided.
The workpiece 415 is wound up by the transport body 413 while being sent out by the rotation of the transport body 411.

  When the laser oscillator 401 oscillates the laser beam, the laser beam is incident on the first lens 403 and refracted, and is incident on the second lens 405. The second lens 405 emits the incident light so that it converges to one point on the workpiece 415. Light emitted from the second lens 405 is reflected by the first mirror 407 and the second mirror 409 and enters the workpiece 415.

  The first lens 403 is held by a first holding member (not shown) so as to be movable in the moving direction (X-axis direction) of the workpiece 415 by the transport bodies 411 and 413. Then, the driving force of the stepping motor 3A controlled by the control device 1A is transmitted to a holding member (not shown) by a first driving force transmission mechanism (not shown), and the first lens 403 moves.

The first mirror 407 is held by a second holding member (not shown) so as to be rotatable in a predetermined direction. Then, the driving force of the stepping motor 3B controlled by the control device 1B is transmitted to the second holding member (not shown) by the second driving force transmission mechanism (not shown), and the first mirror 407 rotates. By this rotation, the incident angle and the emission angle of the light incident on the first mirror 407 are changed.
The second mirror 409 is held by a third holding member (not shown) so as to be rotatable in a predetermined direction. Then, the driving force of the stepping motor 3C controlled by the control device 1C is transmitted to a third holding member (not shown) by a third driving force transmission mechanism (not shown), and the second mirror 409 rotates. By this rotation, the incident angle and the emission angle of the light incident on the second mirror 409 are changed.

  Then, by controlling the stepping motors 3A, 3B, and 3C by the control devices 1A, 1B, and 1C, it is possible to irradiate a desired position on the workpiece 415 with a laser beam. Thereby, as shown in FIG. 3, a laser beam can be irradiated on the to-be-processed line 500 which shows the scheduled position of a laser processing. In the figure, a line denoted by reference numeral 501 indicates a processed position after being irradiated with laser light.

  According to the laser scanner device 7 described above, the stepping motors 3A, 3B, 3C for controlling the irradiation position of the laser beam and the control devices 1A, 1B, 1C thereof can be used at low cost while maintaining the rotation accuracy. . That is, the stepping motors 3A, 3B, 3C and their control devices 1A, 1B, 1C can freely use the high-resolution encoder 31 (see FIG. 1) regardless of the cycle number α. Compared to the mainstream coreless motor, the structure is simple and inexpensive. Therefore, the laser scanner device 7 can be provided at low cost while maintaining the irradiation position accuracy of the laser beam.

  As described above, the laser scanner device is exemplified as the electronic device including the control device 1 and the stepping motor M. However, an NC processing machine, a 3D printer, and the like are also a kind of electronic device, and have the same effects as described above.

<Robot>
Next, a robot to which the control device 1 and the stepping motor M described above are applied will be described. As an example of the robot, a vertical articulated robot (six axes) is shown below, but the robot is not limited to these, and may be a double-arm robot or other multi-axis robot. In the description of the robot 8, the above-described stepping motor M will be described as stepping motors 3E, 3F, 3G, 3H, 3I, and 3J.

The robot 8 shown in FIG. 4 is a vertical articulated robot. Such a robot 8 includes a base 81, four arms 82, 83, 84, 85, and a wrist 86, which are sequentially connected.
The base 81 is fixed to a floor surface (not shown) with bolts or the like, for example. The arm 82 is connected to the upper end portion of the base 81 in a posture inclined with respect to the horizontal direction, and the arm 82 can rotate about a rotation axis along the vertical direction with respect to the base 81. It has become. In the base 81, a stepping motor 3E that rotates the arm 82 and a control device 1E that controls the stepping motor 3E are arranged.

  An arm 83 is connected to the distal end portion of the arm 82, and the arm 83 is rotatable about a rotation axis along the horizontal direction with respect to the arm 82. Further, in the arm 83, a stepping motor 3F that rotates the arm 83 with respect to the arm 82 and a control device 1F that controls the stepping motor 3F are installed.

  An arm 84 is connected to the tip of the arm 83, and the arm 84 can rotate about a rotation axis along the horizontal direction with respect to the arm 83. Also, in the arm 84, a stepping motor 3G that rotates the arm 84 with respect to the arm 83 and a control device 1G that controls the stepping motor 3G are installed.

  An arm 85 is connected to the distal end portion of the arm 84, and the arm 85 can be rotated around a rotation axis along the central axis of the arm 84 with respect to the arm 84. Also, in the arm 85, a stepping motor 3H that rotates the arm 85 with respect to the arm 84 and a control device 1H that controls the stepping motor 3H are installed.

  A wrist 86 is connected to the tip of the arm 85. The wrist 86 includes a ring-shaped support ring 861 connected to the arm 85, and a cylindrical wrist body 862 supported at the tip of the support ring 861. The front end surface of the wrist body 862 is a flat surface, and is, for example, a mounting surface on which a manipulator that holds a precision device such as a wristwatch is mounted.

  The support ring 861 can be rotated around a rotation axis along the horizontal direction with respect to the arm 85. The wrist main body 862 is rotatable about a rotation axis along the central axis of the wrist main body 862 with respect to the support ring 861. Further, in the arm 85, a stepping motor 3I that rotates the support ring 861 relative to the arm 85, a control device 1I that controls the stepping motor 3I, and a stepping that rotates the wrist body 862 relative to the support ring 861. A control device 1J for controlling the motor 3J and the stepping motor 3J is arranged. The driving forces of the stepping motors 3I and 3J are transmitted to the support ring 861 and the wrist body 862 by a driving force transmission mechanism (not shown), respectively.

  According to the robot 8 described above, the stepping motors 3E, 3F, 3G, 3H, 3I, and 3J for controlling the rotational positions of the four arms 82, 83, 84, and 85 and the wrist 86, and the control device thereof. 1E, 1F, 1G, 1H, 1I, and 1J can be used at low cost while maintaining rotational accuracy. That is, the stepping motors 3E, 3F, 3G, 3H, 3I, 3J and their control devices 1E, 1F, 1G, 1H, 1I, 1J are free to use the high-resolution encoder 31 (see FIG. 1) regardless of the cycle number α. Compared with the coreless motor which is the mainstream of industrial galvano motors, the structure can be simple and inexpensive. Therefore, the robot 8 can be provided at low cost while maintaining high positional accuracy.

  As described above, the vertical articulated robot is exemplified as the robot 8 including the control device 1 and the stepping motor M. However, a double-arm robot, other multi-axis robots, and the like are also a kind of robot, and have the same effects as described above. .

<Modification>
The stepping motor control device, the control method, and the robot have been described based on the illustrated embodiment. However, the present invention is not limited to this, and the configuration of each unit is an arbitrary function having the same function. It can be replaced with the configuration of In addition, any other component may be added to the present invention. For example, the following modifications may be included in the present invention.

<Modification 1>
In the embodiment and the application example described above, a part of the processing unit 10 and the driving unit 20 excluding the A-phase driving unit 26 and the B-phase driving unit 27, a part of or all of the position detecting unit 32 and the electrical angle detecting unit 40. It may be realized by the CPU executing the control program. In this case, the control program causes the CPU to function as each component. More specifically, the control program controls a stepping motor that rotates a rotor by a magnetic flux generated by supplying an exciting current to a coil corresponding to each of a plurality of phases. , A detection position signal Pn indicating the position of the rotor is multiplied by a coefficient K to function as a position generation unit 30 that generates a detection electric angle signal φ indicating the current electric angle, and a current amplitude command signal Id indicating the amplitude of the current; Based on the detected electrical angle signal φ, the electrical angle command unit 23 is configured to generate an electrical angle command signal θ indicating the electrical angle of the excitation current to be applied to the coil corresponding to each of the plurality of phases.

<Modification 2>
In the embodiment and the application example described above, the drive unit 20 generates the A-phase excitation current Ia and the B-phase excitation current Ib based on the current amplitude command signal Id, the detected electrical angle signal φ, and the detected position signal Pn. The present invention is not limited to this, and each excitation current may be generated based on the current amplitude command signal Id and the detected electrical angle signal φ. In this case, the advance angle generation unit 22 is not essential. That is, the electrical angle command signal θ may be generated without considering the advance angle signal degree.

<Recording device>
Hereinafter, an example of a recording apparatus including the laser scanner device 7 to which the control device 1 and the stepping motor 3 described above are applied will be described. In the following description, components similar to those of the laser scanner device 7 described above are denoted by the same reference numerals, and the description thereof may be simplified or omitted. In the following drawings, the scale of each layer and each member is shown different from the actual scale so that each layer and each member can be recognized.

<Configuration Example 1 of Recording Apparatus>
First, an image recording apparatus 100 that is a label printing apparatus including a drum-like platen will be described as a configuration example 1 of a recording apparatus including a laser scanner device 7 to which the control device 1 and the stepping motor 3 described above are applied. FIG. 5 is a front view schematically showing the image recording apparatus 100 including the laser scanner device 7 to which the stepping motor control device 1 and the stepping motor 3 according to the embodiment described above are applied.

  As shown in FIG. 5, in the image recording apparatus 100, a single sheet S (web) whose both ends are wound around a feeding shaft 120 and a winding shaft 140 in a roll shape as a recording medium is formed between the feeding shaft 120 and the winding shaft. The sheet S is stretched between the take-up shafts 140, and the sheet S is conveyed from the feeding shaft 120 to the take-up shaft 140 along the thus-carrying conveyance path Sc. The image recording apparatus 100 is configured to record (form) an image on the sheet S by discharging functional liquid onto the sheet S conveyed along the conveyance path Sc. The sheet S is not particularly limited. A paper structure, a film system, or the like, or a multilayer structure in which these layers are bonded together via an adhesive (for example, a base material of a seal piece) can be applied. For example, paper-based materials include high-quality paper, cast paper, art paper, and coated paper, and film-based materials include synthetic paper, PET (Polyethylene terephthalate), and PP (Polypropylene).

  The image recording apparatus 100 includes, as a schematic configuration, a feeding unit 102 that feeds out a sheet S from a feeding shaft 120, a processing unit 103 that records an image on the sheet S fed out from the feeding unit 102, A laser scanner device 7 that cuts out the recorded sheet S and a winding unit 104 that winds the sheet S around a winding shaft 140 are configured. In the following description, among both surfaces of the sheet S, the surface on which an image is recorded may be referred to as the front surface, and the opposite surface may be referred to as the back surface.

  The feeding unit 102 includes a feeding shaft 120 around which the end of the sheet S is wound, and a driven roller 121 around which the sheet S drawn from the feeding shaft 120 is wound. The feeding shaft 120 supports the end of the sheet S by winding it with the surface of the sheet S facing outward. Then, when the feeding shaft 120 rotates clockwise in FIG. 5, the sheet S wound around the feeding shaft 120 is fed to the process unit 103 via the driven roller 121. Incidentally, the sheet S is wound around the feeding shaft 120 via a core tube (not shown) that is detachable from the feeding shaft 120. Therefore, when the sheet S of the feeding shaft 120 is used up, a new core tube around which the roll-shaped sheet S is wound can be mounted on the feeding shaft 120 and the sheet S of the feeding shaft 120 can be replaced. It has become.

  The process unit 103 supports the sheet S fed from the feeding unit 102 with a platen drum 130 as a support unit, and the recording head 151 and the like disposed in a head unit 115 disposed along the outer peripheral surface of the platen drum 130. Thus, an appropriate process is performed to record an image on the sheet S.

  The platen drum 130 is a cylindrical drum that is rotatably supported around a drum shaft 130s by a support mechanism (not shown), and winds the sheet S conveyed from the feeding unit 102 to the winding unit 104 from the back side. It is hung. The platen drum 130 supports the sheet S from the back side while receiving the frictional force between the plate S and rotating in the conveyance direction Ds of the sheet S. Incidentally, the process unit 103 is provided with driven rollers 133 and 134 that fold back the sheet S on both sides of the winding part around the platen drum 130. Among these, the driven roller 133 wraps the surface of the sheet S between the driven roller 121 and the platen drum 130 and folds the sheet S. On the other hand, the driven roller 134 wraps the surface of the sheet S between the platen drum 130 and the driven roller 141 and folds the sheet S. In this manner, by folding the sheet S on the upstream and downstream sides in the transport direction Ds with respect to the platen drum 130, the length of the winding portion Ra of the sheet S around the platen drum 130 can be secured long. Note that an edge sensor Se that detects an end of the other driven roller 131 or the sheet S in the width direction may be disposed between the driven roller 121 and the driven roller 133. Further, another driven roller 132 may be disposed between the driven roller 134 and the driven roller 141.

  The process unit 103 includes a head unit 115, and a recording head 151 is disposed in the head unit 115. In this embodiment, a plurality of recording heads 151 corresponding to different colors are provided, for example, four recording heads 151 corresponding to yellow, cyan, magenta, and black are provided. Each recording head 151 is opposed to the surface of the sheet S wound around the platen drum 130 with a slight clearance (platen gap), and discharges the corresponding color functional liquid from the nozzles by an ink jet method. . Then, each recording head 151 discharges the functional liquid onto the sheet S conveyed in the conveyance direction Ds, whereby a color image is formed on the surface of the sheet S.

  In the present embodiment, UV (ultraviolet) ink (photocurable ink) that is cured by irradiating with ultraviolet rays (light) is used as the functional liquid. Therefore, the head unit 115 of the process unit 103 is provided with a first UV light source 161 (light irradiation unit) in order to temporarily cure the UV ink and fix it to the sheet S. A first UV light source 161 for temporary curing is disposed between each of the plurality of recording heads 151. That is, the first UV light source 161 cures (temporarily cures) the UV ink to such an extent that the shape of the UV ink does not collapse by irradiating weak ultraviolet rays. On the other hand, a second UV light source 162 as a curing unit for main curing is provided on the downstream side in the transport direction Ds with respect to the plurality of recording heads 151 (head units 115). That is, the second UV light source 162 completely cures (mainly cures) the UV ink by irradiating ultraviolet rays stronger than the first UV light source 161. By performing the temporary curing and the main curing in this manner, the color image formed by the plurality of recording heads 151 can be fixed on the surface of the sheet S.

The laser scanner device 7 is provided so as to partially cut out or divide the sheet S on which an image is recorded. The configuration of the laser scanner device 7 is the same as the configuration described above (see FIG. 3), and thus detailed description thereof is omitted.
The laser light oscillated by the laser oscillator 401 of the laser scanner device 7 includes a first lens 403 whose position is controlled by the stepping motor 3A, and a first mirror 407 whose rotational position (angle) is controlled by the stepping motors 3B and 3C. And the sheet S, which is a workpiece, is irradiated through the second mirror 409 and the like. Thus, the irradiation position of the laser beam LA irradiated to the sheet S is controlled by the stepping motors 3A, 3B, 3C, and can be irradiated to a desired position on the sheet S. In the sheet S, the portion irradiated with the laser beam LA is melted and partially cut out or divided.

  In addition, the part cut out or divided by the laser beam LA may be discharged and stored in the storage unit by a discharge unit (not shown) after the melting, or the winding shaft is held on the base material by the adhesive of the sheet S 140 may be conveyed.

  Further, in this configuration, the example in which the sheet S is cut out or divided after the image is recorded by fusing using the laser scanner device 7 is not limited to this. It may be configured to cut out or divide the position.

  According to the image recording apparatus 100 described above, the stepping motors 3A, 3B, 3C for controlling the irradiation position of the laser beam LA and the control apparatuses 1A, 1B, 1C can be used at low cost while maintaining the rotation accuracy. it can. That is, the stepping motors 3A, 3B, 3C and their control devices 1A, 1B, 1C can freely use the high-resolution encoder 31 (see FIG. 1) regardless of the cycle number α. Compared to the mainstream coreless motor, the structure is simple and inexpensive. Therefore, the image recording apparatus 100 can be provided at low cost while performing cutting and dividing with high positional accuracy.

<Configuration Example 2 of Recording Apparatus>
Next, a printer (recording apparatus) 211 having a flat platen will be described as a configuration example 2 of a recording apparatus having the laser scanner device 7 to which the control device 1 and the stepping motor 3 described above are applied. FIG. 6 is a front view schematically showing a printer 211 including a laser scanner device 7 to which the stepping motor control device 1 and the stepping motor 3 according to the embodiment described above are applied.

As shown in FIG. 6, the printer (recording apparatus) 211 employs an inkjet system that ejects liquid onto a sheet S from a plurality of recording heads (liquid ejection heads) as a printing system. The printing process is performed while sequentially feeding one sheet S (web) wound in a roll shape, and the printed sheet S is again wound in a roll shape. Since the sheet S is the same as that of the above-described configuration example 1, description thereof is omitted here.
In the present embodiment, an XYZ orthogonal coordinate system is set in which the width direction of the sheet S in the horizontal plane is the X direction, the conveyance direction of the sheet S orthogonal to the X direction is the Y direction, and the vertical direction is the Z direction.

  The printer 211 includes a main body unit 214 that executes a printing process, a feeding unit 213 that supplies the sheet S to the main body unit 214, and a winding unit 215 that winds up the sheet S discharged from the main body unit 214. Yes.

  The main body 214 includes a main body case 216, the feeding section 213 is installed on the upstream side (−Y side) of the main body case 216 in the transport direction, and the winding section 215 is downstream in the transport direction of the main body case 216 (+ Y side). Is installed. The feed unit 213 is connected to the medium supply unit 216a provided on the side wall 216A on the upstream side (-Y side) of the main body case 216, while the medium provided on the side wall 216B on the downstream side (+ Y side) in the transport direction. A winding unit 215 is connected to the discharge unit 216b.

  The feeding unit 213 includes a support plate 217 attached to a lower portion of the side wall 216A of the main body case 216, a winding shaft 218 provided on the support plate 217, and a feeding table 219 connected to the medium supply unit 216a of the main body case 216. , And a relay roller 220 provided at the tip of the feeding table 219. A sheet S wound around the winding shaft 218 in a roll shape is rotatably supported. The sheet S fed from the roll is wound around the relay roller 220 and converted to the upper surface of the feeding table 219, and is conveyed along the upper surface of the feeding table 219 to the medium supply unit 216a.

  The winding unit 215 includes a winding frame 241, a relay roller 242 and a winding drive shaft 243 provided on the winding frame 241. The sheet S discharged from the medium discharge unit 216b is wound around the relay roller 242 and guided to the winding drive shaft 243, and is wound into a roll shape by the rotational driving of the winding drive shaft 243.

  A plate-like base 221 is installed horizontally in the main body case 216 of the main body 214, and the main body case is partitioned into two spaces by the base 221. A space above the base 221 is a printing chamber 222 that performs a printing process on the sheet S. The printing chamber 222 includes a platen (medium support unit) 228 fixed on the base 221, a recording head (recording processing unit) 236 provided above the platen 228, and a carriage 235 a that supports the recording head 236. Two guide shafts 235 that support the carriage 235a, a valve unit 237, and a laser scanner device 7 that cuts out the sheet S are provided. The two guide shafts 235 are arranged parallel to each other along the transport direction (Y direction), and the carriage 235a is configured to be reciprocally movable in the transport direction.

  The platen 228 includes a box-shaped support base 228a whose upper surface is open, and a mounting plate 228b attached to the opening of the support base 228a. The support base 228a is fixed on the base 221. The interior surrounded by the support base 228a and the mounting plate 228b is a negative pressure chamber. The sheet S is placed on the support surface of the placement plate 228b (the medium support surface that is the upper surface in the + X axis direction in the drawing).

  The mounting plate 228b has a number of suction holes (not shown) penetrating the mounting plate 228b in the thickness direction, and is formed on one side wall of the support base 228a (in this embodiment, the side wall on the −Y side). An exhaust port (not shown) penetrating the side wall is formed. A suction fan (not shown) is connected to the exhaust port. By the suction of the suction fan, a suction force is applied to the sheet S through a large number of suction holes, and the sheet S can be attracted to the support surface of the mounting plate 228b and flattened.

A supply conveyance system including a plurality of conveyance rollers is provided on the upstream side (−Y side) of the platen 228 in the conveyance direction. The supply conveyance system is provided in the vicinity of the first conveyance roller pair 225 provided in the printing chamber 222 in the vicinity of the platen 228, the relay roller 224 provided in the lower space of the main body case 216, and the medium supply unit 216a. Relay roller 223.
The first transport roller pair 225 includes a first drive roller 225a and a first driven roller 225b.

  In the supply conveyance system, the sheet S carried into the main body case 216 from the feeding unit 213 via the medium supply unit 216a is wound from below on the first drive roller 225a via the relay rollers 223 and 224, and Nipped by one transport roller pair 225. Then, with the rotation of the first drive roller 225a driven by a first transport motor (not shown), the first transport roller pair 225 is fed horizontally onto the support surface of the platen 228.

On the other hand, a discharge conveyance system including a plurality of conveyance rollers is provided on the downstream side (+ Y side) of the platen 228 in the conveyance direction. The discharge conveyance system includes a second conveyance roller pair 233 provided on the side opposite to the first conveyance roller pair 225 with respect to the platen 228, a reverse roller 238 and a relay roller 239 provided in a space on the lower side of the main body case 216. And a feed roller 240 provided in the vicinity of the medium discharge portion 216b.
The second transport roller pair 233 includes a second drive roller 233a and a second driven roller 233b. Since the second driven roller 233b is disposed on the printing surface side (upper surface side) of the sheet S, the edge portion in the width direction (X direction) of the sheet S is used in order to avoid damage to the printed image. It is good also as a structure which contact | abuts only to.

  In the discharge conveyance system, the second conveyance roller pair 233 having nipped the sheet S carries out the sheet S from the platen 228 along with the rotation of the second drive roller 233a driven by a second conveyance motor (not shown). The sheet S fed out from the second transport roller pair 233 is transported to the feed roller 240 via the reverse roller 238 and the relay roller 239, and is fed out to the take-up unit 215 via the medium discharge unit 216b by the feed roller 240. .

  In the case of this embodiment, the plurality of recording heads 236 are attached to the carriage 235a via head attachment plates (not shown). The head mounting plate is configured to be movable in the medium width direction (X direction) on the carriage 235a. The position of the head mounting plate can be controlled, and by moving the head mounting plate in the medium width direction (X direction), the plurality of recording heads 236 can be integrated into a line feed operation. The recording heads 236 are arranged on the head mounting plate so as to be arranged at regular intervals in the medium width direction so that adjacent recording heads 236 are alternately arranged in two stages in the medium transport direction (Y direction).

  The plurality of recording heads 236 are connected to the valve unit 237 via ink supply tubes (not shown). The valve unit 237 is provided on the inner wall of the main body case 216 in the printing chamber 222 and is connected to an ink tank (ink storage unit) (not shown). The valve unit 237 supplies the ink supplied from the ink tank to the recording head 236 while temporarily storing the ink.

  On the lower surface (nozzle formation surface) of the recording head 236, a large number of ink discharge nozzles are arranged in the medium width direction (X direction). The recording head 236 ejects ink supplied from the valve unit 237 from the ink discharge nozzle toward the sheet S on the platen 228 to perform printing. Note that the recording head 236 may have a plurality of ink ejection nozzle arrays. In this case, when performing color printing of 4 colors or 6 colors, if ink is assigned to each ink discharge nozzle row for each color type, a single recording head 236 can eject a plurality of colors of ink. Become.

  A laser scanner device 7 is provided in the main body case 216 of the main body 214. The laser scanner device 7 is provided on the downstream side (Y side) from the ink ejection position described above. The laser scanner device 7 is provided so as to partially cut out or divide the sheet S on which an image is recorded. The configuration of the laser scanner device 7 is the same as the configuration described above (see FIG. 3), and thus detailed description thereof is omitted.

  The laser light oscillated by the laser oscillator 401 of the laser scanner device 7 includes a first lens 403 whose position is controlled by the stepping motor 3A, and a first mirror 407 whose rotational position (angle) is controlled by the stepping motors 3B and 3C. And the sheet S, which is a workpiece, is irradiated through the second mirror 409 and the like. Thus, the irradiation position of the laser beam LA irradiated to the sheet S is controlled by the stepping motors 3A, 3B, 3C, and can be irradiated to a desired position on the sheet S. In the sheet S, the portion irradiated with the laser beam LA is melted and partially cut out or divided.

  In addition, the part cut out or divided by the laser beam LA may be discharged and stored in a storage unit by a discharge unit (not shown) after melting, or wound while being held on the base material by the adhesive of the sheet S. It may be conveyed to the part 215.

  Further, in the present configuration, the example in which the sheet S is cut out or divided after the image by ink ejection is recorded by fusing using the laser scanner device 7 is not limited thereto, but the image is recorded. A configuration in which a desired position is cut out or divided may be used.

  According to the above-described printer (recording device) 211, the stepping motors 3A, 3B, and 3C for controlling the irradiation position of the laser beam LA and the control devices 1A, 1B, and 1C (see FIG. 3) maintain the rotation accuracy. However, it can be used inexpensively. That is, the stepping motors 3A, 3B, 3C and their control devices 1A, 1B, 1C can freely use the high-resolution encoder 31 (see FIG. 1) regardless of the cycle number α. Compared to the mainstream coreless motor, the structure is simple and inexpensive. Therefore, the printer (recording apparatus) 211 can be provided at a low cost while performing cutting and dividing with high positional accuracy.

  As described above, the stepping motor control device, the control method, the electronic device, the robot, the recording device, and the control program have been described based on the illustrated embodiments, configuration examples, and modifications. However, the present invention is not limited thereto. Instead, the configuration of each part can be replaced with any configuration having the same function. In addition, any other component may be added to the present invention.

DESCRIPTION OF SYMBOLS 1 ... Control apparatus, M ... Stepping motor, 10 ... Processing part, 20 ... Drive part, 21 ... Speed detection part, 22 ... Advance angle generation part, 23 ... Electrical angle command part, 30 ... Position generation part, 31 ... Encoder, 32: Position detecting unit, Pc: Position command signal, Pn: Detected position signal, Pe ... Position error signal, Vd ... Speed command signal, Vn ... Detection speed signal, Ve ... Speed error signal, Id ... Current amplitude command signal, degree ... Advance angle signal, φ ... Detection electrical angle signal, θ ... Electrical angle command signal, Ida ... A phase current command signal, Idb ... B phase current command signal, Ia ... A phase current, Ib ... B phase current.

Claims (10)

A stepping motor control device that rotates a rotor by magnetic flux generated by supplying an excitation current to a coil corresponding to each of a plurality of phases,
A position generation unit that generates a position signal including the detected position information of the rotor;
An electrical angle detector that outputs electrical angle detection signals, including electrical angle information obtained by multiplying the position signal by a coefficient;
Based on an amplitude signal including amplitude information of the excitation current and the detection signal of the electrical angle, a drive unit that outputs the excitation current toward the coil;
Stepping motor control device. The drive unit is
A speed detector that outputs a speed detection signal including speed information of the rotor based on the position signal;
An advance angle generation unit that generates an advance angle signal, including advance angle information based on the speed detection signal;
A command unit that generates an electrical angle command signal including electrical angle information of the excitation current based on the advance angle signal and the electrical angle detection signal;
The stepping motor control device according to claim 1, wherein the excitation current is output based on the amplitude signal and the electrical angle command signal.   Calculating a deviation between a signal indicating a target value of a target position of the rotor and the position signal as a position error signal, and including a speed command signal including speed information of the rotor based on the position error signal; 3. A processing unit that generates and calculates a deviation between the speed command signal and the speed detection signal as a speed error signal, and generates the amplitude signal based on the speed error signal. Stepper motor control device.   The stepping motor control device according to claim 1, wherein the position generation unit has a resolution of 18 bits or more. When the coefficient is K, the number of electrical angle periods per rotation of the rotor is α, the electrical angle control resolution is β, and the resolution of the position generation unit is γ,
The coefficient K is the following equation:
K = (α × β / γ) × (β-1)
The stepping motor control device according to claim 1, wherein the stepping motor control device is given by: A stepping motor control device according to any one of claims 1 to 5,
Stepper motor,
Electronic equipment comprising. A stepping motor control device according to any one of claims 1 to 5,
Stepper motor,
A recording apparatus comprising: A stepping motor control device according to any one of claims 1 to 5,
Stepper motor,
Robot equipped with. A stepping motor control method for controlling a stepping motor that rotates a rotor by magnetic flux generated by supplying an exciting current to a coil corresponding to each of a plurality of phases,
Obtaining a position signal indicating the position of the rotor;
Generating an electrical angle detection signal including electrical angle information obtained by multiplying the position signal by a coefficient;
A stepping motor control method for outputting the excitation current based on an amplitude signal indicating an amplitude of a current and a detection signal of the electrical angle. Generating an electrical angle detection signal including electrical angle information obtained by multiplying a position signal indicating the position of the rotor by a coefficient;
A stepping motor control program for generating an electrical angle command signal indicating an electrical angle of the excitation current based on an amplitude signal indicating an amplitude of the current and an electrical angle detection signal.

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