JP2011061967A - Stepping motor control apparatus and carrier apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stepping motor control unit for reducing power consumption when a motor stops as much as possible, and to provide a carrier. <P>SOLUTION: The stepping motor control unit is provided with: a phase excited state determination means for determining the phase excitation state of the motor; a drive means driving the motor; a phase excited state changing means changing the phase excitation state of the motor by the driving means; and a current value changing means changing a value of current flowing to the motor. When the phase excitation state determination means determines that the phase excited state of the motor is that of high-power consumption when the motor stops, the phase excited state changing means changes the phase excited state of the motor to that of low power consumption. The current-value changing means changes the value of the current flowing to the motor to a current value suitable for the phase excited state of small power consumption. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a stepping control device that controls a stepping motor that uses a 1-2 phase excitation method, and a transport device that includes the stepping control device.

  In a stepping motor control device, an excitation method is used that maintains a stop position of a motor by continuously supplying a hold current to the phase at the time of stop when the stepping motor is stopped. Further, the excitation method in which the hold current continues to flow is used for the purpose of quickly converging the vibration of the motor shaft immediately after the motor operation is stopped and immediately after the power is turned on.

  In a step motor control device, a 1-2 phase excitation method in which one-phase excitation and two-phase excitation are alternately repeated is used to perform precise position control.

  In the 1-2 phase excitation method, depending on the stop position, only one phase is excited (one phase excitation state) and two phases are excited (two phase excitation state), but the hold current is stopped. Regardless of the phase excitation state of the position, it was set to a certain value. Although the power consumption differs between the one-phase excitation state and the two-phase excitation state, the hold current is set based on the phase excitation state where the power consumption is high. For this reason, in the phase excitation state with low power consumption, there existed a problem that useless electric power was consumed.

  Therefore, in Patent Document 1, in order to reduce the power consumption due to the hold current that flows when the motor using the 1-2 phase excitation method is stopped, the phase excitation state is confirmed when the motor is stopped, and the one phase excitation state is set. Further, a technique for switching the magnitude of the hold current to flow depending on whether the two-phase excitation state is present is disclosed. As a result, power consumption can be optimized, and wasteful power is not consumed in each phase excitation state.

  In order to reduce the power consumption at the time of stopping as much as possible, it is preferable that the phase excitation state with the smaller power consumption is always at the time of stopping. However, in patent document 1, the phase excitation state at the time of a stop cannot be selected.

  Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a stepping motor control device and a conveyance device that consume as little power as possible when stopped.

  In order to solve the above problems, a stepping motor control device according to the present invention includes a phase excitation state determination unit that determines a phase excitation state of a motor, a drive unit that drives the motor, and a phase excitation state of the motor that is the drive unit. Phase excitation state changing means for changing the current value flowing through the motor, and current value changing means for changing the current value flowing to the motor. When the motor is stopped, the phase excitation state of the motor is consumed by the phase excitation state determining means. When it is determined that the phase excitation state is high in power, the phase excitation state changing means changes the phase excitation state of the motor to a phase excitation state with low power consumption, and the current flowing through the motor is changed by the current value changing means. The value is changed to a current value suitable for the phase excitation state with low power consumption.

  In the stepping motor control device according to the present invention, the phase excitation state determination unit measures a current value flowing through the motor, and when the measured current value is larger than a predetermined value, the phase excitation state of the motor is It is determined that the phase excitation state has a high power consumption, and when the measured current value is smaller than a predetermined value, it is determined that the phase excitation state of the motor is a phase excitation state with a low power consumption. May be.

  In the stepping motor control device according to the present invention, the phase excitation state determination means measures the value of the current flowing through the motor when the motor is stopped, and then determines the phase excitation state of the motor by the phase excitation state change means. If the current value measured before changing the phase excitation state is greater than the current value measured after changing the phase excitation state, change the phase excitation state. When the subsequent phase excitation state is determined to be a phase excitation state with low power consumption, and the current value measured before the change of the phase excitation state is smaller than the current value measured after the change of the phase excitation state The phase excitation state after the change of the phase excitation state may be determined as the phase excitation state in which the power consumption is large.

  Further, the stepping motor control device according to the present invention has pulse counting means for counting the number of pulses input to the driving means for driving the motor, and the phase excitation state determination means is counted by the pulse counting means. The phase excitation state of the motor may be determined based on the number of pulses.

  In the stepping motor control device according to the present invention, the phase excitation state determination unit may determine the phase excitation state of the motor based on information acquired from the drive unit.

  In the stepping motor control device according to the present invention, the driving means may have means for notifying a phase excitation state of the motor.

  In the stepping motor control device according to the present invention, the driving means may have means for counting the number of pulses input to drive the motor.

  In the stepping motor control device according to the present invention, the driving means may drive the motor by a predetermined number of pulses.

  In the stepping motor control device according to the present invention, the phase excitation state changing means may change the phase excitation state of the motor by inputting odd pulses to the driving means.

  In the stepping motor control device according to the present invention, the phase excitation state changing means may change the phase excitation state of the motor by inputting a RESET signal to the driving means.

  In the stepping motor control device according to the present invention, the phase excitation state changing means may change the phase excitation state of the motor by inputting a MODE signal corresponding to the one-phase excitation mode to the driving means. good.

  In the stepping motor control device according to the present invention, the driving means drives the motor via a one-way gear, and the motor is driven by the rotation direction during normal driving of the motor and the phase excitation state changing means. The direction of rotation when changing the phase excitation state may be different.

  Further, the stepping motor control device according to the present invention may subtract the number of pulses input to start the motor next by the number of pulses input to the driving means when changing the phase excitation state. good.

  In the stepping motor control device according to the present invention, the motor may be set to a home position at a predetermined position, and when the motor is started, it may be started after returning the motor to the home position.

  The stepping motor control device according to the present invention further includes voltage value changing means for changing a voltage value applied to the motor, and the phase excitation state of the motor is consumed by the phase excitation state determining means when the motor is stopped. When it is determined that the phase excitation state has high power, the phase excitation state changing means changes the phase excitation state of the motor to a phase excitation state with low power consumption, and is applied to the motor by the voltage value changing means. The voltage value may be changed to a voltage value suitable for the phase excitation state with low power consumption.

  Moreover, the conveyance apparatus in this invention is provided with the stepping motor control apparatus in the said invention.

  According to the present invention, power consumption at the time of stoppage can be minimized.

It is a block diagram of a stepping motor control device according to an embodiment of the present invention. It is a figure explaining the phase excitation state of the stepping motor which concerns on embodiment of this invention. It is a figure which shows the whole operation | movement flow in the stepping motor control apparatus which concerns on embodiment of this invention. It is a figure which shows the processing operation at the time of determining the phase excitation state in the stepping motor control apparatus which concerns on embodiment of this invention. It is a figure which shows the processing operation at the time of determining the phase excitation state in the stepping motor control apparatus which concerns on embodiment of this invention. It is a figure which shows the processing operation at the time of determining the phase excitation state in the stepping motor control apparatus which concerns on embodiment of this invention. It is a figure explaining operation | movement of the stepping motor which concerns on embodiment of this invention. It is a figure explaining operation | movement of the stepping motor which concerns on embodiment of this invention. It is a figure which shows the processing operation at the time of determining the phase excitation state in the stepping motor control apparatus which concerns on embodiment of this invention. It is a figure which shows the processing operation at the time of changing the phase excitation state in the stepping motor control apparatus which concerns on embodiment of this invention. It is a figure explaining the control at the time of changing the phase excitation state in the stepping motor control apparatus which concerns on embodiment of this invention. It is a figure explaining the control at the time of changing the phase excitation state in the stepping motor control apparatus which concerns on embodiment of this invention. It is a figure explaining the control at the time of changing the phase excitation state in the stepping motor control apparatus which concerns on embodiment of this invention. It is a figure which shows the processing operation at the time of changing the phase excitation state in the stepping motor control apparatus which concerns on embodiment of this invention. It is a figure which shows the processing operation at the time of changing the phase excitation state in the stepping motor control apparatus which concerns on embodiment of this invention. It is a block diagram of a stepping motor control device according to an embodiment of the present invention. It is a figure which shows the whole operation | movement flow in the stepping motor control apparatus of this invention.

  Next, an embodiment of the present invention will be described. Specifically, it has the following characteristics in the control when the stepping motor using the 1-2 phase excitation method is stopped. In short, the present invention detects the phase excitation state at the time of stop and, as a result, if the phase excitation state has a high power consumption, the current value is changed after the phase excitation state is changed to the phase excitation state with a low power consumption. It is characterized by switching. The above features will be specifically described with reference to the following drawings.

  FIG. 1 is a block diagram of a stepping motor control apparatus according to an embodiment of the present invention. Here, for example, it is assumed that the stepping motor control device uses a constant current method. A stepping motor control apparatus according to an embodiment of the present invention includes a control unit that controls the whole, a motor (stepping motor), a drive pattern table that stores motor drive pattern data, and a drive unit that drives the motor. Phase excitation state determination means for determining which phase of the motor is excited; phase excitation state variable means for switching the phase in which the motor is excited; a REF voltage setting unit for determining a current value to be supplied to the motor; The resistor Rsa is connected in series to the A phase and A / phase of the motor, and the resistor Rsb is connected in series to the B phase and B / phase.

  Here, the motor is a four-phase stepping motor. In the 1-2 phase excitation method, as shown in FIG. 2, (1) only the A phase is H level at the first step, and (2) the second step. A phase, B phase at H level, (3) B phase only at 3rd step at H level, (4) B phase at 4th step, A / phase at H level, (5) A / phase at 5th step (6) A / phase at the 6th step, B / phase at the H level, (7) Only at the b / phase at the 7th step, (8) B / phase at the 8th step, A The motor is rotated by setting each phase to H level in the order of H level and returning to (9) (1). The first, third, fifth and seventh steps are in a one-phase excitation state, and the second, fourth, sixth and eighth steps are in a two-phase excitation state.

  From the control means, based on the information in the drive pattern table, a RESET signal for initializing the drive means, a CLK signal for determining the motor operating frequency, a CW / CCW signal for selecting the motor rotation direction, and two-phase excitation A MODE signal for selecting a motor excitation method such as 1-2 phase excitation and an ENABLE signal for enabling the motor are sent to the driving means. Further, a REF signal for selecting a current value to be supplied from the control means to the motor is sent to the REF voltage setting unit. Based on the signal from the control means, the drive means rotates the motor.

  FIG. 3 is a diagram showing an overall operation flow in the stepping motor control apparatus according to the embodiment of the present invention. The operation flow will be described with reference to FIG.

  A RESET signal is input for the purpose of initializing the driving means (S101). The excitation mode is selected (S102). Here, 1-2 phase excitation is selected. When holding is performed for the purpose of maintaining the stop position before the motor operation (S103, Yes), the process proceeds to step S104. When the hold is not performed (S103, No), the process proceeds to the next step S106.

  An initial hold current value HIs of the driving means is set (S104). When the initial state is the one-phase excitation state, the current value for the one-phase excitation is set, and when the two-phase excitation state is set, the current value for the two-phase excitation is set. Whether the initial state is the one-phase excitation state or the two-phase excitation state is determined by the initial specification of the driving means 4. ENBLE is input (S105). Here, the hold is started, and a current flows to the initial phase.

  It is determined whether or not to operate the stepping motor (S106). If it does not operate (S106, No), it waits until it operates, and if it operates (S106, Yes), it proceeds to the next step S107.

  The rotation direction (CW / CCW) of the motor 2 is set (S107). A drive current value Ik is set (S108). ENABLE is input (S109). Here, when holding is performed in step S103, it is not necessary to input ENBALE again. A CLOCK having a frequency to be operated is input (S110). The stepping motor operates under the conditions set above.

  When stopping (S112), CLOCLK is stopped and it progresses to the following step S113. Here, when not holding (S113, No), ENABLE is stopped (S114), and it waits until the next operation of the stepping motor. In the case of holding (S113, Yes), the process proceeds to the next step S115.

  A hold current HIa is set (S115). Normally, the hold current HIa when holding is smaller than the drive current Ik when the load is operating, so that the value of the current flowing to the motor is set low for the purpose of reducing power consumption. In this case, since there is a time when it is unknown whether the one-phase excitation state or the two-phase excitation state, a current value that does not step out in either case is set. In general, when the same current value is set, the torque is lower in the one-phase excitation state than in the two-phase excitation state, so the current value in the one-phase excitation state is set. Note that, under the same conditions, regarding the power consumption, the one-phase excitation state is lower than the two-phase excitation state.

  It is confirmed whether or not the one-phase excitation state is present (S116). Here, how to confirm the phase excitation state, that is, the phase excitation state determination flow will be described later.

  In the case of the one-phase excitation state (S116, Yes), the process proceeds to the next step S117. In the case of the two-phase excitation state (S116, No), the process proceeds to the phase excitation state variable flow, and the phase excitation state is changed to the one-phase excitation state. The current value is also changed to the current value for the one-phase excitation state (S118), and the process proceeds to step S117. The phase excitation state variable flow will be described later.

  When canceling the hold (S117, Yes), ENABLE is stopped (S108), and the process proceeds to step S106. As a result, the hold is released. When the hold is not released (S117, No), the process proceeds to step S106.

  In this flow, it is described that the one-phase excitation state consumes less power and the torque is smaller than the two-phase excitation state. However, the stepping motor in which the condition is reversed, that is, the one-phase excitation state When driving a stepping motor that consumes more power than the two-phase excitation state, it is confirmed in step 116 whether it is a two-phase excitation state, not a one-phase excitation state. If the current value for two-phase excitation is changed, and the two-phase excitation state is not set, the phase excitation state may be changed to the two-phase excitation state and changed to the current value for two-phase excitation.

  In this flow, the initial stage of the driving means is described as one-phase excitation. However, when the initial stage is two-phase excitation, the phase excitation state variable flow is performed after step S103 to change the phase excitation state after the variable. A suitable current value may be set. Furthermore, this flow is an example of the processing operation in the present embodiment, and it is conceivable that the current value is switched while the stepping motor is driven.

  FIG. 4 is a diagram illustrating a processing operation when the phase excitation state is determined in the stepping motor control apparatus according to the embodiment of the present invention. That is, FIG. 4 is a diagram showing a phase excitation state determination flow in step S116 of FIG.

  First, the current value of the tapping motor is detected (S201). Specifically, the voltage values at Rsa and Rsb in FIG. 1 may be measured to calculate the sum of current values (Rsa and Rsb). Next, the current value detected in S201 is compared with a predetermined value (S202). When the detected value is smaller than the predetermined value (S202, Yes), it is determined that the phase excitation state is the one-phase excitation state (S203). When the detected value is larger than the predetermined value (S202, No), it is determined that the phase excitation state is the two-phase excitation state (S204).

  The predetermined value here may be a value between the current value flowing when the two-phase excitation state is set and the current value flowing when the one-phase excitation state is set, but a value around the middle is desirable in consideration of variation. This flow shows a case where the power consumption in the one-phase excitation state is larger than the power consumption in the two-phase excitation state. In the opposite case, the above determination is also reversed.

  FIG. 5 is a diagram illustrating a processing operation when the phase excitation state is determined in the stepping motor control device according to the embodiment of the present invention. That is, FIG. 5 is a diagram showing a phase excitation state determination flow in step S116 of FIG.

First, the current value Ia of the stepping motor 2 is detected (S301). The phase excitation state is changed (S302). The current value Ib after the phase excitation state change is detected (S303). Ia and Ib are compared, and if Ia is large (S304, Yes), it is determined that the phase excitation state is the one-phase excitation state (S305),
When it is smaller (S304, No), it is determined that the phase excitation state is the two-phase excitation state (S306).

  This flow shows a case where the power consumption in the two-phase excitation state is larger than the power consumption in the one-phase excitation state. In the opposite case, the above determination is also reversed.

Although the means for determining the phase excitation state by the current detection method is described in FIGS. 4 and 5, other methods for determining the phase excitation state by detecting the current are also conceivable. For example, a two-phase excitation state may be determined if current flows in both Rsa and Rsb during excitation, and a one-phase excitation state may be determined if only one of them is excited.

  FIG. 6 is a diagram illustrating a processing operation when the phase excitation state is determined in the stepping motor control apparatus according to the embodiment of the present invention. That is, FIG. 6 is a diagram showing a phase excitation state determination flow in step S116 of FIG. In order to perform this processing operation, the stepping motor control device is provided with pulse counting means for counting pulses when the stepping motor operates.

  The number of pulse counts during the stepping motor operation, that is, from the initial time to the end of operation is acquired (S401). It is confirmed whether the count number is 2n + 1 (odd number) (S402). If it is not 2n + 1 (odd number) (S402, Yes), it is determined that the phase excitation state is the one-phase excitation state (S403). If 2n + 1 (odd number) (No in S402), it is determined that the phase excitation state is the two-phase excitation state (S404).

  In the 1-2 phase excitation, since the 1 phase excitation state and the 2 phase excitation state are repeated in order, it can be determined whether or not it is the same as the initial phase excitation state by checking whether it is an odd number or not. it can. When the initial state is the one-phase excitation state and the pulse count after the operation is an odd number, the state after the operation is a two-phase excitation state. That is, the above flow is a flow when the initial state is the one-phase excitation state, and if the initial state is the two-phase excitation state, the determination opposite to the above flow is performed.

  FIG. 7 is a diagram for explaining the operation of the stepping motor according to the embodiment of the present invention.

When the stepping motor takes a load and rises to the target speed as fast as possible, if the speed is above the self-starting range, that is, the speed range where the motor can start rotating, the target speed A method of gradually increasing from a lower speed is used. This method is called through-up. Similarly, the method of gradually decreasing the speed is called through-down. In general, the step-up motor control apparatus often uses this through-up / down control, and the through-up / down table (number of speed VS pulses) is stored in advance in the memory area of the control apparatus.

  A series of operations in FIG. 7 will be described. (1) First, through-up is performed using a predetermined through-up table (speed VS pulse number). For example, the speed is increased to the target speed with 100 pulses. (2) A constant speed operation is performed until a trigger such as a sensor is turned on. The number of pulses at this time depends on the ON timing of the sensor. (3) Through-down according to the through-down table. For example, use 150 pulses and gradually decrease the speed.

  At this time, since the number of pulses required for the through-down is determined in advance, the count number is determined before the stop is reached. In the above example, 150 pulses are used. That is, in the above example, the number of counts until the sensor is stopped when the sensor is ON is determined as 150 pulses.

  In this way, by using a predetermined number of pulses and counting the pulses, the number of pulses is known before the stepping motor completely stops, so it is possible to perform control to optimize the current value almost simultaneously with the stop. it can. For this reason, it is not necessary to pass a current to determine the phase excitation state, and wasteful power consumption can be reduced.

  In the 1-2 phase excitation method, there are 8 steps as shown in FIG. A means for notifying the driving means when it comes to each excitation step is provided in the driving means. When notified, the pulse count can be initialized without losing the phase excitation information by initializing the count value of the pulse count means.

  FIG. 8 is a diagram for explaining the operation of the stepping motor according to the embodiment of the present invention.

  A series of operations in FIG. 8 will be described. (1) First, through-up is performed using a predetermined through-up table. For example, the speed is increased to the target speed with 100 pulses. (2) An operation corresponding to a predetermined number of pulses is performed. For example, it operates for 300 pulses. (3) Through-down according to a predetermined through-down table. For example, use 150 pulses and gradually decrease the speed. At this time, since the necessary number of pulses (100 + 300 + 150 pulses) required from the start to the stop of the motor is determined in advance, the count number is determined before the stop.

  By doing so, since the number of pulses necessary for driving is known before driving the stepping motor, it is possible to determine the phase excitation state at the time of stopping without counting pulses. In addition, since it is not necessary to count the number of pulses, the current value can be set to an optimum value without incurring complicated processing.

  FIG. 9 is a diagram illustrating a processing operation when the phase excitation state is determined in the stepping motor control device according to the embodiment of the present invention. That is, FIG. 9 is a diagram showing a phase excitation state determination flow in step S116 of FIG. The flow of FIG. 9 is a flow in the case where the phase excitation state can be grasped by the driving means by the method described above.

  The phase excitation state is acquired from the drive means (S501). It is confirmed whether or not the acquired phase excitation state is a one-phase excitation state (S502). When it is in the one-phase excitation state (S502, Yes), it is determined that the phase excitation state is the one-phase excitation state (S503). When it is in the two-phase excitation state (S502, No), it is determined that the phase excitation state is the two-phase excitation state (S504).

  By doing in this way, it can set to an optimal electric current value, without causing a complicated process.

  FIG. 10 is a diagram illustrating a processing operation when the phase excitation state is changed in the stepping motor control apparatus according to the embodiment of the present invention. That is, FIG. 10 is a diagram showing a phase excitation state variable flow in step S118 of FIG.

  A 2n + 1 (odd number) pulse is input (S601). That is, in the 1-2 phase excitation method, since the 1 phase excitation state and the 2 phase excitation state are repeated in order, the phase excitation state can be changed by inputting 2n + 1 pulses.

  FIG. 11 is a diagram illustrating control when changing the phase excitation state in the stepping motor control device according to the embodiment of the present invention.

  When the stepping motor 1 rotates, the one-way gear 6 meshed with the motor gear 5 also rotates. When the motor gear 5 rotates counterclockwise and the one-way gear 6 rotates clockwise, the one-way clutch 7 attached to the one-way gear 6 does not operate, so that the shaft 8 that serves as the rotation shaft of the one-way gear 6 is operated. Does not rotate.

  Conversely, when the motor gear 5 rotates clockwise and the one-way gear 6 rotates counterclockwise, the one-way clutch 7 operates to transmit the rotation of the one-way gear 6 to the shaft 8, so that the shaft 8 rotates.

When changing the phase excitation state, 2n + 1 pulses are input after setting the motor gear 5 to rotate counterclockwise. In a normal operation other than the operation of changing the phase excitation state, the motor gear 5 is set to rotate clockwise.

  Without the above configuration, if 2n + 1 pulses are applied, the original intended stop position will be shifted by 2n + 1 pulses. However, by performing the above configuration, the operation is originally intended. The phase excitation state can be changed without impairing the stop position.

  FIG. 12 is a view for explaining control when changing the phase excitation state in the stepping motor control apparatus according to the embodiment of the present invention.

  In order to change the phase excitation state, 2n + 1 pulses are input (S701). The number Pa of pulses at the next activation is acquired from the drive pattern table (S702). The number of pulses (2n + 1) input in step S701 is subtracted from the number of pulses Pa acquired in step S702 (S703). The number of pulses calculated in step S703 is set in the drive pattern table (S704).

  In order to change the phase excitation state every time when the stepping motor is repeatedly operated / stopped, if 2n + 1 pulses are input, an error of (2n + 1 pulses) × number of operations will be accumulated. By performing the − (2n + 1) pulse at the next drive, it becomes possible to prevent the accumulation of errors.

  FIG. 13 is a diagram for explaining control when changing the phase excitation state in the stepping motor control apparatus according to the embodiment of the present invention.

  When the stepping motor 1 rotates, the sheet 3 mounted on the drive shaft of the stepping motor 1 rotates. The sheet 3 is provided with a projection 4 so that the sensor 2 can detect the projection 4 when the sheet 3 is rotated. The position where the protrusion 4 is detected is set as the home position of the stepping motor 1, and when 2n + 1 pulses are input to change the phase excitation state, the operation returns to the home position before the next drive.

  When 2n + 1 pulses are generated by the phase excitation state variable means, the stop is made at a position shifted by 2n + 1 pulses from the originally intended stop position. However, depending on the stop position, other members (not shown) are adversely affected. there is a possibility. As described above, by performing the home position operation, it is possible to move to a position where there is no adverse effect.

  FIG. 14 is a diagram showing a processing operation when changing the phase excitation state in the stepping motor control apparatus according to the embodiment of the present invention. That is, FIG. 14 is a diagram showing a phase excitation state variable flow in step S118 of FIG.

  A RESET signal is input (S801). That is, the driving means with low power consumption is used in the initial phase excitation state, and the driving means is initialized when changing the phase excitation state. This is a method that can be performed when a phase excitation state with low power consumption is set as the initial phase excitation state.

  FIG. 15 is a diagram illustrating a processing operation when the phase excitation state is changed in the stepping motor control device according to the embodiment of the present invention. That is, FIG. 15 is a diagram showing a phase excitation state variable flow in step S118 of FIG.

  Switch to the one-phase excitation mode (S901). That is, when changing the phase excitation state, the one-phase excitation mode (MODE signal) provided in the driving means is used to switch to the one-phase excitation state.

  FIG. 16 is a block diagram of the stepping motor control apparatus according to the embodiment of the present invention. In the configuration of FIG. 16, unlike the configuration of FIG. 1, the control unit sends a REF signal for selecting a drive voltage to be applied to the motor to the drive voltage setting unit instead of a current value to be supplied to the motor.

  FIG. 17 is a diagram showing an overall operation flow in the stepping motor control apparatus of the present invention. The flow in FIG. 17 is different from the flow in FIG. 2 in steps S1104, S1108, and S1115.

  In step S1104, unlike the step S104 in FIG. 2, the initial hold voltage value HVs of the driving means is set. When the initial state is the one-phase excitation state, the voltage value for the one-phase excitation is set, and when the two-phase excitation state is set, the voltage value for the two-phase excitation is set.

  In step S1108, unlike step S108 in FIG. 2, a drive voltage value Vk is set.

  In step S1115, unlike step S115 of FIG. 2, a hold voltage value HVa is set. Usually, the hold voltage value HVa at the time of holding is smaller than the drive voltage value Vk at the time of operation with a large load, so the voltage value applied to the motor is set low for the purpose of reducing power consumption. Here, since there is a time when it is unknown whether the one-phase excitation state or the two-phase excitation state, a voltage value that does not step out in either case is set. Generally, when the same voltage value is set, since the torque is lower in the one-phase excitation state than in the two-phase excitation state, the voltage value in the one-phase excitation state is set. Note that, under the same conditions, regarding the power consumption, the one-phase excitation state is lower than the two-phase excitation state.

  The present invention has been described above by the preferred embodiments of the present invention. While the invention has been described with reference to specific embodiments thereof, various modifications and changes can be made to these embodiments without departing from the broader spirit and scope of the invention as defined in the claims. is there.

  For example, the processing operation in the above-described embodiment can be executed by hardware, software, or a combined configuration of both.

  When processing by software is executed, the program is loaded from a ROM (Read Only Memory) storing a program recording a processing sequence to a memory (RAM) in a computer incorporated in dedicated hardware. The program can be read and executed, or the program can be installed and executed on a general-purpose computer capable of executing various processes.

  For example, the program can be recorded in advance on a hard disk or ROM as a recording medium. Alternatively, the program is stored on a removable recording medium such as a magnetic disk such as a floppy (registered trademark) disk, an optical disk such as a CD (Compact Disc) or DVD (Digital Versatile Disc), or a magneto-optical disk such as an MO (Magneto Optical) disk. It is possible to store (record) temporarily or permanently.

  Such a removable recording medium can be provided as so-called package software.

  The program is installed on the computer from the above-described removable recording medium, transferred wirelessly from the download site to the computer, or transferred to the computer via a network such as a LAN (Local Area Network) or the Internet. On the other hand, the computer can receive the transferred program and install it on a recording medium such as a built-in hard disk.

  In addition to being executed in time series in accordance with the processing operations described in the above embodiment, the processing capability of the apparatus that executes the processing, or a configuration to execute in parallel or individually as necessary Is also possible.

  In addition, the system described in the above embodiment can be configured to have a logical set configuration of a plurality of devices or to mix the functions of each device.

1 Stepping motor (motor)
2 Sensor 3 Seat 4 Projection 5 Motor Gear 6 One Way Gear 7 One Way Clutch 8 Shaft

Japanese Patent Laid-Open No. 11-127598

Claims (16)

Phase excitation state determination means for determining the phase excitation state of the motor;
Drive means for driving the motor;
Phase excitation state changing means for changing the phase excitation state of the motor by the driving means;
Current value changing means for changing a current value flowing through the motor,
When the motor is stopped, when the phase excitation state of the motor is determined to be a phase excitation state with high power consumption by the phase excitation state determination means, the phase excitation state of the motor is consumed by the phase excitation state change means. A stepping motor control device characterized by changing to a phase excitation state with low power and changing the current value flowing through the motor to a current value suitable for the phase excitation state with low power consumption by the current value changing means.   The phase excitation state determination means measures a current value flowing through the motor, and when the measured current value is larger than a predetermined value, the phase excitation state of the motor is a phase excitation state with a large power consumption. 2. The stepping motor according to claim 1, wherein when the measured current value is smaller than a predetermined value, the phase excitation state of the motor is determined to be a phase excitation state with low power consumption. Control device.   The phase excitation state determination means measures a current value flowing through the motor when the motor is stopped, and then changes a phase excitation state of the motor by the phase excitation state change means and measures a current value flowing through the motor. When the current value measured before the change of the phase excitation state is larger than the current value measured after the change of the phase excitation state, the power consumption is small in the phase excitation state after the change of the phase excitation state. If the current value measured before the phase excitation state change is smaller than the current value measured after the phase excitation state change, the phase excitation after the phase excitation state change is determined. The stepping motor control device according to claim 1, wherein the state is determined to be a phase excitation state in which the power consumption is large. Pulse counting means for counting the number of pulses input to the driving means for driving the motor;
2. The stepping motor control device according to claim 1, wherein the phase excitation state determination unit determines the phase excitation state of the motor based on the number of pulses counted by the pulse count unit.   The stepping motor control device according to claim 1, wherein the phase excitation state determination unit determines a phase excitation state of the motor based on information acquired from the driving unit.   6. The stepping motor control device according to claim 5, wherein the driving means includes means for notifying a phase excitation state of the motor.   6. The stepping motor control apparatus according to claim 5, wherein the driving means includes means for counting the number of pulses input to drive the motor.   6. The stepping motor control apparatus according to claim 5, wherein the driving unit drives the motor by a predetermined number of pulses.   9. The stepping motor control device according to claim 1, wherein the phase excitation state changing unit changes the phase excitation state of the motor by inputting an odd number of pulses to the driving unit. .   9. The stepping motor control device according to claim 1, wherein the phase excitation state changing unit changes a phase excitation state of the motor by inputting a RESET signal to the driving unit. .   9. The phase excitation state changing means changes the phase excitation state of the motor by inputting a MODE signal corresponding to a one-phase excitation mode to the driving means. 10. Stepping motor control device described in 1. The drive means drives the motor via a one-way gear,
The rotation direction when the motor is normally driven and the rotation direction when the phase excitation state of the motor is changed by the phase excitation state changing means are different from each other. The stepping motor control device described.   10. The stepping motor control device according to claim 9, wherein the number of pulses input to start the motor is subtracted by the number of pulses input to the driving means when changing the phase excitation state. . The motor has a predetermined position as a home position,
The stepping motor control device according to any one of claims 1 to 13, wherein when starting the motor, the motor is started after returning the motor to the home position. Voltage value changing means for changing the voltage value applied to the motor;
When the motor is stopped, when the phase excitation state determining unit determines that the phase excitation state of the motor is a phase excitation state with high power consumption, the phase excitation state changing unit consumes the phase excitation state of the motor. 2. The phase excitation state with low power is changed, and the voltage value applied to the motor by the voltage value changing means is changed to a voltage value suitable for the phase excitation state with low power consumption. The stepping motor control device according to any one of 14.   A conveyance apparatus provided with the stepping motor control apparatus of any one of Claim 1 to 15.

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