JP2017073861A - Drive control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease the number of wires between a control device and a drive unit.SOLUTION: A control device 3 comprises: a first DC power supply 31 for supplying a direct current power with a first polarity; and a second DC power supply 32 for supplying a direct current power with a second polarity opposite to the first polarity; an electric power supply changeover unit 33 for connecting either of the power supplies to power lines 5A, 5B; and a signal transmitting/receiving circuit 34 for transmitting a signal by turning on/off an electric path which passes through the power lines 5A, 5B while the second DC power supply 32 is connected to the power lines 5A, 5B and receiving the signal by detecting the on/off status of the electric path. A motor-operated valve drive device 2 comprises: an electric motor 20 for driving a motor-operated valve 1; a power supply unit 23 for supplying the direct current power with the first polarity to the electric motor 20; and a signal transmitting/receiving circuit 24 for transmitting a signal by turning on/off an electric path which passes through the power lines 5A, 5B while the direct current power with the second polarity is connected to the power lines 5A, 5B and receiving the signal by detecting the on/off status of the electric path.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a system for controlling the operation of a drive target. An example of the driving target may be a motor operated valve. “Electric valve” refers to a valve driven by an electric actuator. The electric actuator is a drive unit that operates by supplying electric power, and typical examples thereof include an electric motor and an electromagnetic solenoid. The valve is a device that is interposed in a flow path for transporting fluid, and that opens and closes the flow path and adjusts its opening. Typical examples of the valve include a butterfly valve and a ball valve. Typical examples of fluid are liquid, gas, powder and the like.

  In one usage form of the motor-operated valve, the operation of the motor-operated valve driving device that drives the motor-operated valve is controlled by a control device that is arranged separately from the motor-operated valve. The electric valve driving device includes, for example, an electric motor as an electric actuator for operating the electric valve, a full-close limit switch that detects full-close of the electric valve, and a full-open limit switch that detects full-open of the electric valve. . In addition, the electric valve driving device may include a valve position detector for detecting the opening degree of the electric valve. The control device supplies power to the motor-operated valve driving device via a power line. The electric actuator is operated by this electric power, and the electric valve is driven in the opening direction or the closing direction. In order to monitor the operating state of the motor-operated valve, a state signal indicating the state of the fully-closed limit switch and the fully-open limit switch is transmitted from the motor-operated valve driving device to the control device via a signal line. In the case where the valve position detector is provided, a detection signal (a signal indicating the valve opening degree) of the valve position detector is further transmitted from the electric valve driving device to the control device via a signal line.

  Accordingly, the wiring between the control device and the motor-operated valve driving device includes the power line, the first signal line for transmitting the state signal of the fully closed limit switch, the second signal line for transmitting the state signal of the fully opened limit switch, and the valve position. A third signal line for transmitting the detection signal of the detection signal is included. These wirings are routed between the control device and the motor-operated valve driving device in a state in which mutual insulation is ensured, mutual interference is avoided, and damage from the outside is avoided. Depending on the application, since it is necessary to accommodate the wiring in the pipe, it is also necessary to lay the pipe between the control device and the electric valve drive device.

Japanese Patent Laid-Open No. 08-215330 JP 2005-293121 A

  As described above, the wiring between the control device and the electric valve drive device includes the first and second signal lines in addition to the power line, and further includes the third signal line when the valve position needs to be detected. . For this reason, since the number of wires between the control device and the motor-operated valve driving device is large, the cost of the wiring material is high and a great deal of labor is required for the wiring work. In addition, when it is necessary to ensure the insulation state between the wirings and avoid interference, the work is added. When laying piping for accommodating wiring, if the number of wiring is large, it is necessary to lay piping having a large diameter corresponding to the number of wires, which requires material cost and labor accordingly.

This problem also occurs in a system that controls an object to be driven other than the electric valve.
Accordingly, one object of the present invention is to provide a drive control system capable of reducing the number of wires between the control device and the drive device, thereby simplifying the configuration for controlling the drive target. It is to be.

  The present invention provides a drive control system including a drive device that drives a drive target, a control device that controls the drive device, and a power line that supplies DC power from the control device to the drive device. The control device includes: a first DC power source that supplies DC power of a first polarity to the power line; and a second DC power source that supplies DC power of a second polarity opposite to the first polarity to the power line. A power switching unit that connects one of the first DC power source and the second DC power source to the power line, and a current path that passes through the power line during a period in which the second DC power source is connected to the power line. A signal is received by detecting on / off of a current path passing through the power line during a period in which the second DC power supply is connected to the power line, and a control unit side transmission unit that transmits / receives a signal by turning on / off The control device side receiving unit is operated, and the control device side transmitting unit is operated and a signal received by the control device side receiving unit is acquired during a period in which the second DC power source is connected to the power line. It includes a controller-side communication control unit. The drive device includes: an electric actuator that drives the drive target; an actuator control unit that controls the electric actuator; a power supply unit that supplies DC power of the first polarity to the electric actuator; and the second polarity A drive unit side transmission unit for transmitting a signal by turning on / off a current path through the power line during a period in which the direct current power is supplied to the power line, and the second polarity DC power is supplied to the power line. A drive-unit-side receiving unit that receives a signal by detecting on / off of a current path passing through the power line during a period, and a period during which the second polarity DC power is supplied to the power line. Driving device side communication control unit that operates the driving device side transmission unit and acquires the signal received by the driving device side receiving unit , Including the.

  According to this configuration, the drive device has the electric actuator that drives the drive target, and the electric actuator is driven by the DC power supplied from the control device via the power line. The control device has a power supply switching unit, and this power supply switching unit connects the first DC power supply or the second DC power supply to the power line. When the first DC power source is connected to the power line, the first polarity DC power is supplied to the power line, and when the second DC power source is connected to the power line, the second polarity DC power is supplied to the power line. That is, the power supply switching unit reverses the polarity of the DC power supplied to the power line.

  During the period when the first polarity DC power is supplied, the power supply unit supplies DC power to the electric actuator, whereby the electric actuator drives the drive target. On the other hand, during the period when the DC power of the second polarity is supplied to the power line, communication between the control device and the driving device is performed by turning on / off the current path passing through the power line. Specifically, the control device side transmission unit turns the current path on / off by the control of the control device side communication control unit, the drive device side reception unit detects the on / off of the current path, and the detection signal is sent to the drive device. A signal can be sent from the control device to the driving device by the acquisition by the side communication control unit. On the other hand, the drive device side transmission unit turns the current path on / off by the control of the drive device side communication control unit, the control device side reception unit detects the on / off of the current path, and the control signal on the control device side communication control As the unit acquires, a signal can be transmitted from the driving device to the control device.

By inverting the polarity of the DC power supplied to the power line, it is possible to reliably synchronize the communication processes executed in the control device and the driving device driving device.
In this way, since communication between the control device and the drive device can be achieved using the power line, wiring of a signal line for communication between the control device and the drive device is not required. As a result, the number of wires can be reduced, and a configuration for avoiding interference between the power line and the signal line can be omitted. Therefore, the configuration of the wiring becomes simple, the wiring material cost can be reduced accordingly, and the wiring work can be reduced, so that the cost can be greatly reduced. Also, when the wiring is housed in the pipe, the pipe diameter can be reduced, or a configuration for avoiding signal interference in the pipe can be omitted, so that a significant cost reduction can be achieved.

  Furthermore, since the signal path is transmitted by turning on / off the current path, it is hardly affected by the wiring length between the control device and the drive device, and therefore, long-distance communication is possible. That is, the present invention can also be applied to an application in which the control device and the drive device are arranged far apart. Further, since the current path is turned on / off, the speed (frequency) of the signal can be reduced as compared with the case where the signal is superimposed on the power line by a coil or a capacitor. Therefore, an inexpensive configuration can be applied to the transmission unit and the reception unit. As a result, the cost can be reduced.

  In one embodiment of the present invention, the control device side transmission unit includes a phototransistor interposed in the current path, and a light emitting element optically coupled to the phototransistor, and the control device side reception unit includes: A light emitting diode interposed in the current path so as to be forward with respect to the DC power of the second polarity; and a light receiving element optically coupled to the light emitting diode; A control connected in parallel to a series circuit of the phototransistor of the device-side transmitting unit and the light-emitting diode of the control-device-side receiving unit so as to be forward with respect to the DC power of the first polarity. A device-side diode, and the drive-device-side transmission unit includes a phototransistor interposed in the current path, and a phototransistor A light emitting diode interposed in the current path so as to be in a forward direction with respect to the DC power of the second polarity, and the light emitting diode. An optically coupled light receiving element, wherein the driving device is connected in parallel to a series circuit of the phototransistor of the driving device side transmitting unit and the light emitting diode of the driving device side receiving unit. It further includes a driving device side diode connected so as to be in a forward direction with respect to the DC power of polarity.

  According to this configuration, when the first DC power source is connected to the power line and DC power having the first polarity is supplied to the power line, the current from the first DC power source passes through the control device side diode and is further driven. It passes through the diode on the device side. Therefore, regardless of the operations of the control device side transmission unit and the drive device side transmission unit, the current path passing through the power line is in a conductive state, and stable electric power is supplied to the electric actuator via the power supply unit.

  On the other hand, when the second DC power supply is connected to the power line and DC power having the second polarity is supplied to the power line, the control device side diode and the driving device side diode are in a non-conductive state. Therefore, the current path through the power line is only the path through the series circuit of the phototransistor of the control device side transmission unit and the light emitting diode of the control device side reception unit in the control device. Only the path through the series path of the unit phototransistor and the drive unit side receiving unit.

  Therefore, the phototransistor of the transmission device side transmission unit is turned on by turning on the light emitting device optically coupled to the phototransistor, while the light emitting device optically coupled to the phototransistor of the control device side transmission unit is turned on. / Turn off. Then, since the phototransistor of the control device side transmission unit is turned on / off, the light emitting diode of the driving device side reception unit is turned on / off accordingly, and this is detected by the light receiving element optically coupled to the light emitting diode. . The drive device side communication control unit acquires the detection signal of the light receiving element. Thus, a signal can be transmitted from the control device to the driving device.

  In addition, the light emitting element optically coupled to the phototransistor of the drive unit drive unit side transmission unit is made conductive by setting the light emitting element optically coupled to the phototransistor of the control unit side transmission unit to the light emitting state. Turn on / off. Then, the phototransistor of the driving device side transmission unit is turned on / off, and accordingly, the light emitting diode of the control device side receiving unit is turned on / off, and this is detected by the light receiving element optically coupled to the light emitting diode. . The control device side communication control unit acquires the detection signal of the light receiving element. Thus, a signal can be transmitted from the driving device to the control device.

The current path formed when the second DC power supply is connected to the power line forms a current loop that is not easily affected by the wiring length, and is thus advantageous for long-distance wiring.
In one embodiment of the present invention, the power supply switching unit connects the second DC power supply to the power line for a predetermined time at a constant interval, and connects the first DC power supply to the power line at other times.

According to this configuration, the DC power source connected to the power line is switched from the first DC power source to the second DC power source at regular intervals, and when a predetermined time elapses in this state, the DC power source is switched again to the first DC power source. . Accordingly, communication between the control device and the drive device can be performed at regular intervals, so that periodic communication can be performed.
In one embodiment of the present invention, the control device side communication control unit controls the drive target by driving the control device side transmission unit during a period in which the second DC power supply is connected to the power line. The command signal is sent to the power line, the response signal from the drive device is obtained from the signal received by the control device-side receiving unit, and the drive device-side communication control unit receives the DC power of the second polarity. Is acquired from the signal received by the driving device side receiving unit, and the driving device side transmitting unit is driven to change the state of the driving target. A response signal representing the power actuating line, and the actuator control unit responds to the command signal acquired by the drive device side communication control unit. To control the mediator.

According to this configuration, a command signal can be transmitted from the control device to the drive device by communication using the power line, and a response signal representing the state of the drive target can be transmitted from the drive device to the control device. Accordingly, the operation of the drive target can be controlled and the state of the drive target can be monitored in the control device without connecting the control device and the drive device with a dedicated signal line.
In one embodiment of the present invention, a period in which the second DC power supply is connected to the power line is a communication period, and the communication period is a command period in which a command signal is transmitted from the control device to the drive device; Communication between the control device and the drive device is executed by dividing into a response period in which a response signal is transmitted from the drive device to the control device.

With this configuration, a period in which the second DC power supply is connected to the power line is defined as a communication period, and the communication period is divided into a command period and a response period. Therefore, communication through the power line between the control device and the drive device can be realized while avoiding interference between the command signal and the response signal.
The command period and the response period may have the same length, but they do not necessarily have to be the same length. Further, it is not necessary for the entire communication period to be the command period or the response period, and there may be a period that is neither the command period nor the response period. Furthermore, the command period does not need to be continuous within the communication period, and may be dispersed in time. Similarly, the response period need not be a continuous period in the communication period, and may be dispersed in time.

  In one embodiment of the present invention, the control device-side communication control unit causes the control device-side transmission unit to send a pulse-like command signal representing a command content by a pulse width to the power line during the command period, and the drive When the drive-side receiving unit receives a pulse-like command signal during the command period, the device-side communication control unit interprets the command content based on the pulse width.

According to this configuration, the command content can be expressed by the pulse width, and the control command can be transmitted from the control device to the drive device. The pulse width is the length of a period during which the control device side transmission unit turns the current path on or off.
In one embodiment of the present invention, the control device-side communication control unit causes the control device-side transmission unit to send a command signal representing a command content by frequency to the power line during the command period, so that the drive device-side communication control is performed. When the unit receives a command signal during the command period, the unit interprets the command content based on the frequency.

According to this configuration, it is possible to transmit the control command from the control device to the drive device by expressing the command content by the frequency. The frequency is a frequency at which the control device side transmission unit turns on / off the current path.
In one embodiment of the present invention, the control device-side communication control unit causes the control device-side transmission unit to send a pulse-like command signal representing the command content by the number of pulses to the power line during the command period, and the drive When the drive-side receiving unit receives a pulse-like command signal during the command period, the device-side communication control unit interprets the command content based on the number of pulses.

According to this configuration, the command content can be expressed by the number of pulses, and the control command can be transmitted from the control device to the drive device. The number of pulses corresponds to the number of times the control device side transmission unit turns on / off the current path.
In one embodiment of the present invention, the control device-side communication control unit sends a pulse-like command signal representing the command content from the control device-side transmission unit to the power line during the command period. When the driving device side receiving control unit receives the pulsed command signal during the command period, the driving device side communication control unit interprets the command content based on the reception timing of the pulse within the command period. .

According to this configuration, it is possible to transmit the control command from the control device to the drive device by representing the command content by the generation timing of the pulsed command signal. The pulse-like command signal is generated when the control device side transmission unit turns on / off the current path.
In one embodiment of the present invention, the control device side communication control unit causes the command signal including a pair of pulses representing the command contents by the generation interval to be sent from the control device side transmission unit to the power line during the command period. When the driving device side receiving unit receives a pair of pulses during the command period, the driving device side communication control unit interprets the command content based on the reception interval of the pair of pulses.

According to this configuration, it is possible to transmit the control command from the control device to the drive device by representing the command content by the interval between the pair of pulses within the command period. The pulse is generated when the control device side transmission unit turns on / off the current path.
In one embodiment of the present invention, the control device side communication control unit causes the control device side transmission unit to send a command signal representing a command content by serial data communication to the power line during the command period. The side communication control unit receives the command signal by serial data communication via the drive device receiving unit during the command period, and interprets the command content.

According to this configuration, the control command can be transmitted from the control device to the drive device by serial data communication realized by the control device-side transmission unit turning on / off the current path.
In one embodiment of the present invention, the drive device side communication control unit causes the drive device side transmission unit to send a pulse-like response signal indicating the state of the drive target to the power line during the response period. When the control device-side receiving unit receives a pulse-like response signal during the response period, the control device-side communication control unit interprets the response content based on the pulse width.

According to this configuration, the response content can be represented by the pulse width, and the state of the drive target can be transmitted from the drive device to the control device. The pulse width is the length of a period during which the drive unit side transmission unit turns on or off the current path.
In one embodiment of the present invention, the drive device side communication control unit causes the drive device side transmission unit to send a response signal representing the state of the drive target by frequency to the power line during the response period, and the control device. When the control device side receiving unit receives the response signal during the response period, the side communication control unit interprets the response content based on the frequency.

According to this structure, the response content can be represented by the frequency, and the state of the drive target can be transmitted from the drive device to the control device. The frequency is a frequency at which the driving device side transmission unit turns on / off the current path.
In one embodiment of the present invention, the drive device side communication control unit causes the drive device side transmission unit to send a pulse-like response signal representing the state of the drive target to the power line during the response period. When the control device-side receiving unit receives a pulse-like response signal during the response period, the control device-side communication control unit interprets the response content based on the number of pulses.

According to this configuration, the response content can be represented by the number of pulses, and the state of the drive target can be transmitted from the drive device to the control device. The number of pulses corresponds to the number of times the driving device side transmission unit turns on / off the current path.
In one embodiment of the present invention, the drive device side communication control unit sends a pulse-like response signal representing the state of the drive target from the drive device side transmission unit during the response period according to the generation timing within the response period. When the control device side communication control unit receives a pulse-like response signal during the response period, the control device side communication control unit transmits the response content based on the reception timing of the pulse within the response period. Is interpreted.

According to this configuration, the response content can be expressed by the generation timing of the pulse-like response signal, and the state of the drive target can be transmitted from the drive device to the control device. The pulse-like response signal is generated when the drive unit side transmission unit turns on / off the current path.
In one embodiment of the present invention, the drive device side communication control unit sends a response signal including a pair of pulses representing the state of the drive target by the generation interval from the drive device side transmission unit to the power line during the response period. When the control device side receiving unit receives a pair of pulses during the response period, the control device side communication control unit interprets the response content based on the reception interval of the pair of pulses.

According to this configuration, the response content can be expressed by the interval between the pair of pulses within the response period, and the state of the drive target can be transmitted from the drive device to the control device. The pulse is generated when the drive unit side transmission unit turns on / off the current path.
In one embodiment of the present invention, the drive device side communication control unit causes a response signal representing the state of the drive target by serial data communication to be sent from the drive device side transmission unit to the power line during the response period. The control device side communication control unit receives the response signal by serial data communication via the control device side receiving unit during the response period, and interprets the response content.

According to this configuration, the response content (the state of the drive target) can be transmitted from the drive device to the control device by serial data communication realized by turning on / off the current path by the drive device-side transmission unit.
In one embodiment of the present invention, the drive target includes an electric valve driven by the electric actuator, and the instruction based on the instruction signal includes an opening instruction to open the electric valve and a closing instruction to close the electric valve. And the state of the motor-operated valve represented by the response signal includes an open state of the motor-operated valve and a closed state of the motor-operated valve.

  According to this configuration, an opening command for opening the motor-operated valve and a closing command for closing the motor-operated valve can be given from the control device to the driving device. As a result, the electric valve can be controlled to open and close. From the drive device, a response signal indicating an open state (for example, a fully open state) of the motorized valve and a closed state (for example, a fully closed state) of the motorized valve is sent to the control device. Thereby, the control apparatus can monitor the open / close state of the electric valve.

In one embodiment of the present invention, the drive device further includes an open / close detection unit that detects an open state and a closed state of the motor-operated valve, and the response signal represents a detection state of the open / close detection unit.
In one embodiment of the present invention, the drive target includes an electric valve driven by the electric actuator, and the command by the command signal includes an opening degree command for instructing an opening degree of the electric valve, and the response signal The state of the motor-operated valve represented by the following includes the actual opening of the motor-operated valve.

According to this configuration, the opening degree command for instructing the opening degree of the motor-operated valve can be given from the control device to the driving device, whereby the opening degree of the motor-operated valve can be controlled. A response signal indicating the actual opening of the motor-operated valve is sent from the drive device to the control device. Thereby, the control device can monitor the actual opening of the motor-operated valve.
In one embodiment of the present invention, the drive device further includes an opening degree detection unit that detects an actual opening degree of the electric valve, and the response signal represents an actual opening degree detected by the opening degree detection unit.

In one embodiment of the present invention, the power supply unit of the driving device includes a rectifier circuit connected to the power line, and supplies the electric actuator rectified by the rectifier circuit to the electric actuator.
According to this configuration, since the rectifier circuit is connected to the power line, the rectified power is also obtained when the second DC power source is connected to the power line and the second polarity DC power is supplied to the power line. Can be supplied to the electric actuator. Therefore, even when the second DC power supply is connected to the power line, it is possible to supply power to the electric actuator as long as the current path passing through the power line is closed. Accordingly, communication between the control device and the drive device can be realized using the power line without greatly affecting the operation of the drive target.

For example, the control required for a motor-operated valve that is an example of a drive target is, for example, full open, full close, control to a specified opening degree, etc., and strictly controls the opening / closing speed until the target state is reached. Is rarely required. Therefore, a slight change in the opening / closing speed when the second DC power supply is switched is within an allowable range in the drive control of the electric valve.
In one embodiment of the present invention, the power supply unit further includes a capacitor connected to the output side of the rectifier circuit.

  According to this configuration, the capacitor is charged while the first DC power source is connected to the power line. Therefore, during the period when the second DC power source is connected to the power line, the electric power stored in the capacitor is transferred to the electric actuator. Can supply. As a result, the power supply to the drive target is stabilized, and the influence on the operation of the drive target by communication using the power line can be further reduced.

FIG. 1 is a block diagram for explaining a configuration of an electric valve control system according to a first embodiment of the present invention. FIG. 2 is an electric circuit diagram for explaining a specific configuration example of a power supply switching unit provided in the motor-operated valve control system. FIG. 3 is an electric circuit diagram showing a configuration of a main part related to communication of the electric valve control system. FIG. 4 is a time chart for explaining a specific example of the DC power source switching operation by the power source switching unit. FIG. 5 is a time chart for explaining a basic operation example in the communication period. FIG. 6 is a timing chart for explaining an example of a transmission signal. FIG. 7 is a flowchart for explaining an example of processing executed by the control device side microcomputer of the electric valve control system. FIG. 8 is a flowchart for explaining a specific example of the command signal output process (step S10 in FIG. 7). FIG. 9 is a flowchart for explaining a specific example of the response signal reception process (step S11 in FIG. 7). FIG. 10 is a flowchart for explaining a specific example of the error detection process (step S14 in FIG. 7). FIG. 11 is a flowchart for explaining a specific example of the status output process (step S15 in FIG. 7). FIG. 12 is a flowchart for explaining a specific example of processing by the motor-driven valve drive device side microcomputer of the motor-operated valve control system. FIG. 13 is a flowchart for explaining a specific example of the command signal reception process (step S66 in FIG. 12). FIG. 14 is a flowchart for explaining a specific example of the response signal transmission process (step S67 in FIG. 12). FIG. 15 is a flowchart for explaining a specific example of the motor control process (step S69 in FIG. 12). FIG. 16 is a block diagram for explaining a configuration of an electric valve control system according to the second embodiment of the present invention. FIG. 17 is a timing chart for explaining an example of a transmission signal. FIG. 18 is a flowchart for explaining an example of processing executed by the control device side microcomputer of the electric valve control system. FIG. 19 is a flowchart for explaining a specific example of the command signal output process (step S110 in FIG. 18). FIG. 20 is a flowchart for explaining a specific example of the response signal reception process (step S111 in FIG. 18). FIG. 21 is a flowchart for explaining a specific example of the error detection process (step S114 in FIG. 18). FIG. 22 is a flowchart for explaining a specific example of the status output process (step S115 in FIG. 18). FIG. 23 is a flowchart for explaining a specific example of processing by the motor-driven valve drive side microcomputer of the motor-operated valve control system. FIG. 24 is a flowchart for explaining a specific example of the command signal reception process (step S166 in FIG. 23). FIG. 25 is a flowchart for explaining a specific example of the response signal transmission process (step S167 in FIG. 23). FIG. 26 is a flowchart for explaining a specific example of the motor control process (step S170 in FIG. 23). FIG. 27 is an electric circuit diagram showing the configuration of the motor-operated valve control system according to the first comparative example, and shows a configuration example for controlling the opening and closing of the motor-operated valve. FIG. 28 is an electric circuit diagram showing a configuration of the motor-operated valve control system according to the second comparative example, and shows a configuration example for controlling the opening degree of the motor-operated valve.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a block diagram for explaining the configuration of an electric valve control system 101 which is a drive control system according to the first embodiment of the present invention. The motorized valve control system 101 includes a motorized valve driving device 2 that drives the motorized valve 1 as a driving target, a control device 3 for controlling the motorized valve driving device 2, and the control device 3 to the motorized valve driving device 2. It includes a pair of first power line 5A and second power line 5B that supply DC power.

  The motor-operated valve 1 is interposed in a pipe 6 through which fluid flows, and opens and closes the flow path of the pipe 6. The electric valve driving device 2 is mechanically coupled to the electric valve 1 and has an electric motor 20 (DC motor) as an electric actuator for driving the electric valve 1. On the other hand, the control apparatus 3 is arrange | positioned in the place away from the motor operated valve 1, and supplies direct-current power to the motor operated valve drive apparatus 2 via power line 5A, 5B. For example, a plurality of motor-operated valve driving devices 2 are provided corresponding to a plurality of motor-operated valves 1 respectively disposed at a plurality of locations, and the plurality of motor-operated valve driving devices 2 are concentrated by one control device 3. May be controlled automatically.

The electric valve driving device 2 includes an electric motor 20, a motor driving circuit 21 that supplies electric power to the electric motor 20, and a microcomputer 22 that controls the motor driving circuit 21. The microcomputer 22 has a function as an actuator control unit for controlling the electric motor 20 and a function as a drive device side communication control unit for controlling communication with the control device 3. The electric valve driving device 2 further includes a power supply unit 23, a regulator 26, and a signal transmission / reception circuit 24. The power supply unit 23 includes a diode bridge 27 connected to the power lines 5 </ b> A and 5 </ b> B, and a parallel circuit of a resistor R <b> 2 and a capacitor C connected to the output side of the diode bridge 27, and the motor drive to be supplied to the motor drive circuit 21. to generate a voltage _{V M.} The regulator 26 is connected in parallel to the capacitor C on the output side of the diode bridge 27. The signal transmission / reception circuit 24 is interposed between the diode bridge 27 and the first power line 5A. The diode bridge 27 is a rectifier circuit that rectifies and outputs power supplied to the power lines 5A and 5B. The capacitor C stores electric power derived from the power supply line on the output side of the diode bridge 27. A motor drive circuit 21 is connected to the capacitor C. The regulator 26 generates a control voltage V _CC2 (for example, 5 V).

  The electrically operated valve drive device 2 further includes a fully opened detection switch LS1 for detecting the fully opened state of the electrically operated valve 1 and a fully closed detection switch LS2 for detecting the fully closed state of the electrically operated valve 1. The full-open detection switch LS1 and the full-close detection switch LS2 are open / close detection units that are connected to the microcomputer 22 and detect the full open and full close of the motor-operated valve 1 and notify the microcomputer 22 respectively. The full open detection switch LS1 and the full close detection switch LS2 are arranged so as to be operated by a movable member interlocked with the valve body of the electric valve 1, for example, in the driving force transmission path 28 from the electric motor 20 to the electric valve 1. Whether the position of the valve body of the motor-operated valve 1 is a fully open position or a fully closed position is detected. The fully open detection switch LS1 can be configured by a limit switch that is conductive when the motor-operated valve 1 is fully open and is nonconductive when it is not fully open. Similarly, the fully-closed detection switch LS2 can be configured by a limit switch that is conductive when the motor-operated valve 1 is fully closed and is non-conductive when it is not fully closed.

The signal transmission / reception circuit 24 receives a command signal from the control device 3 via the power lines 5A and 5B and transmits it to the microcomputer 22 as a reception signal RD2. The signal transmission / reception circuit 24 receives the transmission signal SD2 representing the state of the motor-operated valve 1 from the microcomputer 22 and transmits the transmission signal to the control device 3 as a response signal via the power lines 5A and 5B. .
The control device 3 includes a DC power supply unit 30, a power supply switching unit 33, a signal transmission / reception circuit 34, and a microcomputer 38. The microcomputer 38 has a function as a control device side communication unit that controls communication with the electric valve driving device 2. The control device 3 further includes an open / close command switch 36 connected to the microcomputer 38 and a display unit 37 connected to the microcomputer 38. The display unit 37 includes a full-open indicator L1 that displays whether the motor-operated valve 1 is fully open, a full-close indicator L2 that displays whether the motor-operated valve 1 is fully closed, and an abnormality indicator L3 that notifies the occurrence of an abnormality.

The DC power supply unit 30 includes a first DC power supply 31 that generates a positive DC voltage V _DD (for example, + 24V) and a second DC power supply 32 that generates a negative DC voltage −V _EE (for example, −12V). In addition, it is configured to obtain electric power from the commercial AC power supply 4 and generate the DC voltages V _DD and -V _EE thereof. The absolute value of the voltage −V _EE generated by the second DC power supply 32 may be equal to or lower than the voltage V _DD generated by the first DC power supply 31.

The power supply switching unit 33 selectively connects the first DC power supply 31 or the second DC power supply 32 to the power lines 5A and 5B. Therefore, when the first DC power supply 31 is connected to the power lines 5A and 5B, DC power having the first polarity (positive polarity) is supplied to the power lines 5A and 5B, and the second DC power supply 32 is connected to the power lines 5A and 5B. Then, DC power of the second polarity (negative polarity) is supplied to the power lines 5A and 5B. The switching operation of the power supply switching unit 33 is controlled by a selection signal SEL given from the microcomputer 38. The DC voltage V _DD generated by the first DC power supply 31 is supplied to a regulator 39 provided in the control device 3, and the control voltage V _CC1 is generated by the regulator 39.

  A signal transmission / reception circuit 34 is interposed in the second power line 5B on the ground side. The signal transmission / reception circuit 34 receives the transmission signal SD1 from the microcomputer 38 and transmits the signal as a command signal to the motor-operated valve driving device 2 through the power lines 5A and 5B. Further, the signal transmission / reception circuit 34 receives the response signal from the electric valve driving device 2 via the power lines 5A and 5B, and passes the response signal to the microcomputer 38 as the reception signal RD1.

The open / close command switch 36 is a manual switch operated by a user. Switching command switch 36, and the movable contact 36c connected to the ground potential, and a open command contacts 36a control voltage _{V CC1} is applied and closing command contact 36b, is open command contacts 36a and closing command contact 36b The microcomputer 38 is connected to input ports S1 and S2, respectively. When the movable contact 36c is connected to the open command contact 36a, the input port S1 becomes the ground potential, and thereby the open command is input to the microcomputer 38. When the movable contact 36c is connected to the close command contact 36b, the input port S2 becomes the ground potential, whereby the close command is input to the microcomputer 38. The microcomputer 38 transmits an open command or a close command to the signal transmission / reception circuit 34, and the signal transmission / reception circuit 34 transmits a command signal representing the command to the motor-operated valve driving device 2 through the power lines 5A and 5B.

When the response signal from the electric valve driving device 2 is given from the signal transmission / reception circuit 34, the microcomputer 38 controls the display states of the fully open display L1 and the fully closed display L2 according to the contents. Moreover, the microcomputer 38 performs abnormality detection processing inside, and when abnormality is detected, abnormality is notified by the abnormality indicator L3.
Communication between the control device 3 and the electric valve drive device 2 is performed exclusively through the power lines 5A and 5B, and a dedicated signal line for transmitting and receiving the command signal and the response signal is provided between them. Not.

  The microcomputer 38 of the control device 3 monitors the input signal from the open / close command switch 36. When the open command is input from the open / close command switch 36, the signal transmission / reception circuit 34 via the power lines 5A and 5B An open command signal is transmitted to the electric valve drive device 2. The microcomputer 22 of the electric valve driving device 2 receives the opening command signal from the power lines 5A and 5B via the signal transmission / reception circuit 24. Then, the microcomputer 22 of the electric valve drive device 2 inputs a normal rotation drive signal to the motor drive circuit 21. Thereby, a drive current in the forward direction is supplied from the motor drive circuit 21 to the electric motor 20, and the electric motor 20 rotates in the forward direction accordingly. Thereby, the valve body of the motor-operated valve 1 is displaced in the opening direction. When the valve body of the motor-operated valve 1 reaches the fully open position, the fully open detection switch LS1 is turned on, and a fully open signal is input to the microcomputer 22. In response to this, the microcomputer 22 stops the input of the forward drive signal to the motor drive circuit 21 and opens the fully open state from the signal transmission / reception circuit 24 to the control device 3 via the power lines 5A and 5B. The response signal that represents is transmitted.

  On the other hand, when a close command is input from the open / close command switch 36, the microcomputer 38 of the control device 3 transmits a close command signal from the signal transmission / reception circuit 34 to the motor-operated valve drive device 2 via the power lines 5A and 5B. To do. The microcomputer 22 of the electric valve driving device 2 receives a full-close command from the power lines 5A and 5B via the signal transmission / reception circuit 24. The microcomputer 22 of the electric valve drive device 2 inputs a reverse drive signal to the motor drive circuit 21. As a result, a drive current in the reverse direction is supplied from the motor drive circuit 21 to the electric motor 20, and the electric motor 20 rotates in the reverse direction accordingly. Thereby, the valve body of the motor-operated valve 1 is displaced in the closing direction. When the valve body of the motor-operated valve 1 reaches the fully closed position, the fully closed detection switch LS2 is turned on, and a fully closed signal is input to the microcomputer 22. In response to this, the microcomputer 22 stops the input of the reverse drive signal to the motor drive circuit 21 and represents the fully closed state from the signal transmission / reception circuit 24 to the control device 3 via the power lines 5A and 5B. Send a response signal.

In this way, the motor-operated valve 1 can be controlled to the fully open state or the fully closed state in accordance with a command signal given from the control device 3 to the motor-operated valve drive device 2 via the power lines 5A and 5B. A response signal indicating the fully open state or the fully closed state of the motor-operated valve 1 can be transmitted from the motor-operated valve driving device 2 to the control device 3 via the power lines 5A and 5B.
FIG. 2 is an electric circuit diagram for explaining a specific configuration example of the power supply switching unit 33. A P-channel field effect transistor (hereinafter referred to as “P-channel FET”) Tr1 is connected in series between the first DC power supply 31 and the first power line 5A, and a resistor 41 is connected between its source and gate. Yes. The gate of the P-channel FET Tr1 is connected to the drain of an N-channel field effect transistor (hereinafter referred to as “N-channel FET”) Tr2, and the source of the N-channel FET Tr2 is connected to the ground potential. The output terminal of the inverter 42 is connected via a resistor 43 to the gate of the N-channel FET Tr2. A selection signal SEL output from the microcomputer 38 is input to the input terminal of the inverter 42.

  On the other hand, the first power line 5A is connected to a photo field effect transistor PTR1 (hereinafter referred to as “phototransistor PTR1”) of the photocoupler 45 via a resistor R1, and a second DC power supply 32 is connected to the phototransistor PTR1. It is connected. Photocoupler 45 includes a light emitting diode LED1 optically coupled to phototransistor PTR1. The selection signal SEL output from the microcomputer 38 is input to the anode terminal of the light emitting diode LED1.

  When the selection signal SEL is logic “0”, that is, at a low level, the N-channel FET Tr2 is turned on, and thereby the P-channel FET Tr1 is turned on. Thereby, the first DC power supply 31 is connected to the power line 5A. At this time, since the light emitting diode LED1 of the photocoupler 45 is in a non-light emitting state, the second DC power supply 32 is disconnected from the power line 5A. In this way, positive polarity (first polarity) DC power can be supplied to the power line 5A.

  When the selection signal SEL is logic “1”, that is, at a high level, the N-channel FET Tr2 is cut off, and thus the P-channel FET Tr1 is cut off, so that the first DC power supply 31 is disconnected from the power line 5A. On the other hand, since a forward voltage is applied to the light emitting diode LED1 of the photocoupler 45, the light emitting diode LED1 emits light, and the phototransistor PTR1 is turned on accordingly. Thereby, the second DC power supply 32 is connected to the power line 5A. In this way, negative polarity (second polarity) DC power can be supplied to the power line 5A. The resistor R1 between the power line 5A and the photocoupler 45 limits the current in the current path passing through the power line 5A when the second DC power supply 32 is connected to the power line 5A.

FIG. 3 is an electric circuit diagram showing a configuration of a main part related to communication of the electric valve control system 101.
First, a specific example of the signal transmission / reception circuits 34 and 24 will be described with reference to FIG. Since the signal transmission / reception circuit 34 on the control device 3 side and the signal transmission / reception circuit 24 on the motor-operated valve driving device 2 side basically have a common configuration, these configurations will be described together below.

The signal transmission / reception circuits 34 and 24 are interposed in series with the power lines 5A and 5B (more specifically, the second power line 5B), and form a current path through the power lines 5A and 5B. The signal transmission / reception circuits 34 and 24 include Schottky diodes 35 and 25, transmission photocouplers 34S and 24S, and reception photocouplers 34R and 24R.
The transmission photocouplers 34S and 24S are light emitting diodes LED11 and LED21 which are light emitting elements which are turned on / off (light emission / non-light emission) in response to transmission signals SD1 and SD2 from the microcomputers 38 and 22, and power lines 5A and 5B ( More specifically, it includes phototransistors PTR11 and PTR21 interposed in series with the second power line 5B). The light emitting diodes LED11 and LED21 and the phototransistors PTR11 and PTR21 are optically coupled, and the phototransistors PTR11 and PTR21 are turned on / off according to the light emission / non-light emission of the light emitting diodes LED11 and LED21, respectively.

The receiving photocouplers 34R and 24R are light-emitting diodes LED12 and LED22 that are interposed in series with the power lines 5A and 5B (more specifically, the second power line 5B), and light-receiving elements connected to the microcomputers 38 and 22. It includes phototransistors PTR12 and PTR22. The light-emitting diodes LED12 and LED22 and the phototransistors PTR12 and PTR22 are optically coupled, and the phototransistors PTR12 and PTR22 are turned on / off according to whether the light-emitting diodes LED12 and LED22 emit light or not. Reception signals RD1 and RD2 corresponding to conduction / cutoff of the phototransistors PTR12 and PTR22 are input to the microcomputers 38 and 22, respectively. The input lines of the reception signals RD1 and RD2 are pulled up to control voltages V _CC1 and V _CC2 through resistors, respectively.

  In the signal transmission / reception circuit 34 of the control device 3, a Schottky diode 35 is connected in parallel to the series circuit of the phototransistor PTR11 of the transmission photocoupler 34S and the light emitting diode LED12 of the reception photocoupler 34R. Similarly, in the signal transmission / reception circuit 24 of the electric valve driving device 2, a Schottky diode 25 is provided in parallel to the series circuit of the phototransistor PTR21 of the transmission photocoupler 24S and the light emitting diode LED22 of the reception photocoupler 24R. It is connected.

Schottky diodes 35 and 25 are connected in the forward direction to positive DC power supplied from first DC power supply 31 to power lines 5A and 5B. On the other hand, the light emitting diodes LED12 and LED22 of the receiving photocouplers 34R and 24R are connected in the forward direction to negative DC power supplied from the second DC power supply 32 to the power lines 5A and 5B.
When the power supply switching unit 33 connects the first DC power supply 31 to the power lines 5A and 5B, the current from the first DC power supply 31 is guided to the first power line 5A through the power supply switching unit 33, and the first power line From 5A, it is supplied to the diode bridge 27 of the electric valve driving device 2. The current from the diode bridge 27 charges the capacitor C and is supplied to the motor drive circuit 21. The current from the motor drive circuit 21 is guided to the signal transmission / reception circuit 24 through the diode bridge 27. The current flows through the Schottky diode 25 to the second power line 5B on the ground side as indicated by the solid arrow. The current guided to the control device 3 through the second power line 5B returns to the first DC power supply 31 through the Schottky diode 35 of the signal transmission / reception circuit 34, as indicated by the solid line arrow. Instead of the Schottky diodes 23 and 35, general PN junction diodes may be used. However, since the forward voltage of the Schottky diode is lower, power consumption can be suppressed. The forward voltage of the PN junction diode is 0.6V to 1.2V, while the forward voltage of the Schottky diode is 0.3V to 0.5V.

  The current flow when the power source switching unit 33 connects the second DC power source 32 to the power lines 5A and 5B is opposite to that when the first DC power source 31 is connected to the power lines 5A and 5B. In the signal transmission / reception circuit 34 on the control device 3 side, the phototransistor PTR11 of the transmission photocoupler 34S is conductive. Similarly, in the signal transmission / reception circuit 24 on the motor-driven valve drive device 2 side, the phototransistor of the transmission photocoupler 24S. Assume that PTR 21 is conducting. In this case, the current from the second DC power supply 32 is generated by the light emitting diode LED12 of the reception photocoupler 34R and the phototransistor of the transmission photocoupler 34S of the signal transmission reception circuit 34 on the control device 3 side, as indicated by the dotted arrows. It passes through the PTR 11 and is led to the second power line 5B on the ground side. The current that has passed through the second power line 5B reaches the signal transmission / reception circuit 24 on the side of the motor-operated valve driving device 2, and as indicated by the dotted arrow, the light-emitting diode LED22 of the reception photocoupler 24R and the transmission photocoupler 24S. It reaches the diode bridge 27 through the phototransistor PTR21. The current from the diode bridge 27 enters the diode bridge 27 again through the resistor R2, and is then led to the first power line 5A. This current passes through the first power line 5A, passes through the power supply switching unit 33, and then reaches the second DC power supply 32. The resistor R2 provided in the motor-operated valve driving device 2 and the resistor R1 provided in the power supply switching unit 33 limit the current when the second DC power supply 32 is connected to the power lines 5A and 5B.

  Since the current path passing through the second DC power supply 32 and the power lines 5A and 5B is closed and the current flows through the current path in this way, the microcomputer 38 on the control device 3 side serves as the control device side transmission unit. The light emitting diode LED11 of the transmission photocoupler 34S is turned off to be in a non-light emitting state. Then, in the signal transmission / reception circuit 24 on the electric valve driving device 2 side, the light emitting diode LED22 of the receiving photocoupler 24R as the driving device side receiving unit is turned off, and the phototransistor PTR22 is turned off accordingly. Therefore, the power lines 5A and 5B are connected from the microcomputer 38 of the control device 3 to the microcomputer 22 of the motor-operated valve drive device 2 by performing on / off control of the light emitting diode LED11 of the transmission photocoupler 34S on the control device 3 side. The signal can be transmitted through.

  By turning on / off the light emitting diode LED11 of the transmission photocoupler 34S on the control device 3 side, the light emitting diode LED12 of the reception photocoupler 34R on the control device 3 side is turned on / off, but the microcomputer 38 transmits a signal. The input signal from the reception photocoupler 34R at that time may be ignored. Of course, the microcomputer 38 may monitor normality / abnormality of the transmission operation using an input signal from the reception photocoupler 34R at the time of signal transmission.

  On the other hand, when the microcomputer 22 on the electric valve driving device 2 side turns off the light emitting diode LED21 of the transmission photocoupler 24S as the driving device side transmission unit to make it non-light emitting, the signal transmission / reception circuit 34 on the control device 3 side. , The light emitting diode LED12 of the receiving photocoupler 34R as the control device side receiving unit is turned off. In response to this, the phototransistor PTR12 is turned off. Accordingly, by turning on / off the light emitting diode LED21 of the transmission photocoupler 24S on the electric valve driving device 2 side, the power line 5A, A signal can be transmitted via 5B.

  By turning on / off the light emitting diode LED21 of the transmission photocoupler 24S on the side of the electric valve driving device 2, the light emitting diode LED22 is turned on / off also in the reception photocoupler 24R on the side of the electric valve driving device 2, but the microcomputer The input signal from the photocoupler for reception 24R at the time of signal transmission may be ignored. Of course, the microcomputer 22 may monitor normality / abnormality of the transmission operation using an input signal from the reception photocoupler 24R at the time of signal transmission.

When the second DC power supply 32 is connected to the power lines 5A and 5B, the Schottky diodes 25 and 35 are held in a cut-off state regardless of whether the light-emitting diodes LED12 and LED22 are on / off. Therefore, the current path passing through the power lines 5A and 5B can be turned on / off by turning on / off the light emitting diodes LED12, LED22.
When the power supply switching unit 33 connects the first DC power supply 31 to the first power line 5 </ b> A, the capacitor C is charged by the current from the first DC power supply 31. When the power supply switching unit 33 switches from the first DC power supply 31 to the second DC power supply 32, the capacitor C is discharged to supply power to the motor drive circuit 21. Therefore, if the time during which the second DC power supply 32 is connected to the power lines 5A and 5B is limited to a sufficiently short time, power supply enough to drive the electric motor 20 can be continued to the motor drive circuit 21. The diode bridge 27 prevents inversion of the voltage between the terminals of the capacitor C and the motor drive circuit 21 even when the second DC power supply 32 is connected to the power lines 5A and 5B. Thereby, the capacitor C is not immediately discharged, and the power supply from the capacitor C to the motor drive circuit 21 can be stabilized.

FIG. 4 is a time chart for explaining a specific example of the switching operation of the first and second DC power supplies 31 and 32 by the power supply switching unit 33, and shows a change in the potential of the first power line 5A. When the power source switching unit 33 is controlled by the microcomputer 38, the power source switching unit 33 periodically switches the first and second DC power sources 31 and 32 at a constant communication interval T1 (for example, 25 msec). Specifically, the power supply switching unit 33 connects the second DC power supply 32 (negative voltage −V _EE ) to the power lines 5A and 5B for a predetermined communication period T2 (for example, 1 msec) within the communication interval T1, and the remaining period Repeats the operation of connecting the first DC power supply 31 (positive voltage V _DD ) to the power lines 5A and 5B. As a result, the operation of supplying negative DC power to the power lines 5A and 5B for the communication period T2 is repeated periodically at the time interval of the communication interval T1.

  FIG. 5 is a time chart for explaining a basic operation example in the communication period T2. FIG. 5A shows a change in potential of the first power line 5A. 5B shows the operation of the phototransistor PTR11 (linked to the transmission signal SD1) of the transmission photocoupler 34S on the control device 3 side, and FIG. 5C shows the reception photocoupler 34R on the control device 3 side. The operation of the phototransistor PTR12 (corresponding to the reception signal RD1) is shown. Further, FIG. 5 (d) shows the operation of the phototransistor PTR21 (linked to the transmission signal SD2) of the transmission photocoupler 24S on the side of the motor-driven valve driving device 2, and FIG. The operation of the phototransistor PTR22 of the photocoupler 24R (corresponding to the reception signal RD2) is shown.

During periods other than the communication period T2, the microcomputers 38 and 22 hold the light emitting diodes LED11 and LED21 of the transmission photocouplers 34S and 24S in a light emitting state. During this period, since the first DC power supply 31 is connected to the power lines 5A and 5B, the light emitting diodes LED12 and LED22 are in the extinguished state. Accordingly, since the phototransistors PTR12 and PTR22 optically coupled to these are in the off state, the reception signals RD1 and RD2 generated by the reception photocouplers 34R and 24R are both high level (control voltages V _CC1 and _VCC , respectively). _CC2 ). In this state, the microcomputer 38 on the control device 3 side controls the power supply switching unit 33 to switch from the first DC power supply 31 to the second DC power supply 32, and starts the communication period T2. Then, in the photocouplers 34R and 24R for reception of the control device 3 and the electric valve drive device 2, the light emitting diodes LED12 and LED22 are switched from the light-off state to the light emitting state. Accordingly, since the phototransistors PTR12 and PTR22 are turned on in response to the start of the communication period T2, the reception signals RD1 and RD2 fall to a low level. Therefore, the microcomputers 38 and 22 of the control device 3 and the electric valve driving device 2 can detect the start of the communication period T2 based on the signals RD1 and RD2 from the reception photocouplers 34R and 24R. Thereby, the communication operation in the control device 3 and the electric valve drive device 2 can be synchronized.

  The microcomputers 38 and 22 respectively provided in the control device 3 and the electric valve drive device 2 divide the communication period T2 into a command period Tc and a response period Ta, and execute processing necessary for mutual communication. The command period Tc is a period assigned to processing for transmitting a command signal from the control device 3 to the motor-operated valve drive device 2. The response period Ta is a period assigned to the process of transmitting a response signal representing the state information of the motor-operated valve 1 from the motor-operated valve driving device 2 to the control device 3. In the example of FIG. 5, the communication period T2 is divided into approximately two equal parts, the first half period is assigned to the command period Tc, and the second half period is assigned to the response period Ta.

  In the command period Tc, the microcomputer 38 of the control device 3 turns on / off the light emitting diode LED11 of the transmission photocoupler 34S by the transmission signal SD1. In conjunction with this, the light emitting diode LED22 of the reception photocoupler 24R of the motor-driven valve driving device 2 is turned on / off, so that the phototransistor PTR22 optically coupled thereto is turned on / off, and the corresponding reception signal RD2 is electrically driven. It is input to the microcomputer 22 of the valve drive device 2. In this way, the command signal can be transmitted from the control device 3 to the electric valve drive device 2.

  In the response period Ta, the microcomputer 22 of the electric valve driving device 2 turns on / off the light emitting diode LED21 of the transmission photocoupler 24S by the transmission signal SD2. In conjunction with this, the light emitting diode LED12 of the receiving photocoupler 34R of the control device 3 is turned on / off, so that the phototransistor PTR12 optically coupled thereto is turned on / off, and the corresponding received signal RD1 is sent to the control device 3 To the microcomputer 38. In this way, a response signal can be transmitted from the electric valve driving device 2 to the control device 3.

  In the command period Tc, the light-emitting diode LED12 of the reception photocoupler 34R of the control device 3 is linked to the on / off (transmission signal SD1) of the light-emitting diode LED11 of the transmission photocoupler 34S, and the reception signal RD1 corresponding thereto is received. Input from the coupler 34R to the microcomputer 38. As described above, the microcomputer 38 ignores this input or uses it for monitoring normality / abnormality of the transmission operation.

  Similarly, during the response period Ta, the light-emitting diode LED22 of the reception photocoupler 24R of the motor-driven valve driving device 2 is interlocked with the on / off (transmission signal SD2) of the light-emitting diode LED21 of the transmission photocoupler 24S. RD2 is input to the microcomputer 22 from the receiving photocoupler 24R. As described above, the microcomputer 22 ignores this input or uses it for monitoring normality / abnormality of the transmission operation.

  FIG. 6 is a timing chart for explaining an example of transmission signals from the transmission photocouplers 34S and 24S. FIG. 6A shows a command period Tc and a response period Ta within the communication period T2. FIG. 6B shows communication (transmission signals SD1, SD2) in the pulse width method. FIG. 6C shows communication (transmission signals SD1, SD2) in the frequency system. FIG. 6 (d) shows communication (transmission signals SD1, SD2) in the pulse number method. FIG. 6 (e) shows communication (transmission signals SD1, SD2) using the pulse timing method. FIG. 6 (f) shows communication (transmission signals SD1, SD2) using a pulse interval method. FIG. 6 (g) shows communication by serial data communication (transmission signals SD1, SD2).

  In the pulse width method shown in FIG. 6 (b), in the command period Tc, the command signal is represented by the transmission signal SD1 expressing the opening command for opening the motorized valve and the closing command for closing the motorized valve 1 by the pulse width. Is sent. That is, the pulse width tw11 of the opening command is different from the pulse width tw12 of the closing command. The pulse width corresponds to the on time length or the off time length of the transmission photocoupler 34S (light emitting diode LED11) (on time length in the example of FIG. 6B). The microcomputer 38 outputs a transmission signal SD1 that holds the light emitting diode LED11 of the transmission photocoupler 34S in the on state or the off state for a time length corresponding to the opening command, thereby transmitting the opening command. Similarly, the microcomputer 38 outputs a transmission signal SD1 that holds the light emitting diode LED11 of the transmission photocoupler 34S in an on state or an off state for a length of time corresponding to the close command, thereby transmitting the close command. The microcomputer 22 of the electric valve driving device 2 monitors the received signal RD2 inputted from the receiving photocoupler 24R, and its pulse width (the ON time length or the OFF time length of the phototransistor PTR22. FIG. 6B). In the example, the open command and the close command are distinguished and detected by measuring the on-time length). In this way, the opening command and the closing command can be transmitted from the control device 3 to the electric valve drive device 2.

  The same applies to the case where the pulse width method is used for transmission of the response signal from the electric valve driving device 2 to the control device 3. That is, in the response period Ta, the response is performed by the transmission signal SD2 expressing the fully-open information indicating that the motor-operated valve 1 is in the fully-open state and the fully-closed information indicating that the motor-operated valve 1 is in the fully-closed state. A signal is transmitted. The pulse width tw21 in the fully open state is different from the pulse width tw22 in the fully closed state. The pulse width corresponds to the on time length or the off time length of the transmission photocoupler 24S (light emitting diode LED21) (on time length in the example of FIG. 6B). The microcomputer 22 outputs a transmission signal SD2 that holds the light emitting diode LED21 of the transmission photocoupler 24S in an on state or an off state for a time length corresponding to the fully opened state, thereby transmitting a response signal representing the fully opened state. . Similarly, the microcomputer 22 outputs the transmission signal SD2 that holds the light emitting diode LED21 of the transmission photocoupler 24S in the on state or the off state for a time length corresponding to the fully closed state, thereby representing the fully closed state. Send a response signal. The microcomputer 38 of the control device 3 monitors the input signal from the receiving photocoupler 34R and its pulse width (the ON time length or the OFF time length of the phototransistor PTR12. In the example of FIG. 6B, the ON time length) Is measured to distinguish between the fully closed state and the fully open state. In this way, response signals representing the fully open state and the fully closed state can be transmitted from the motor-operated valve drive device 2 to the control device 3.

  In the frequency method shown in FIG. 6 (c), in the command period Tc, the command signal is represented by a transmission signal SD1 expressing an open command for opening the motor-operated valve 1 and a close command for closing the motor-operated valve 1 according to the frequency. Sent. That is, the frequency f11 of the opening command is different from the frequency f12 of the closing command. The frequency corresponds to the on / off frequency of the transmission photocoupler 34S (light emitting diode LED11). The microcomputer 38 turns on / off the light emitting diode LED11 of the transmission photocoupler 34S with the transmission signal SD1 of the frequency f11 according to the opening command, thereby transmitting the opening command. Similarly, the microcomputer 38 turns on / off the light emitting diode LED11 of the transmission photocoupler 34S with the transmission signal SD2 having the frequency f12 according to the close command, thereby transmitting the close command. The microcomputer 22 of the electric valve driving device 2 monitors the reception signal RD2 input from the reception photocoupler 24R, and measures its frequency (on / off frequency of the phototransistor PTR22), thereby opening and closing commands. Detected separately. In this way, the opening command and the closing command can be transmitted from the control device 3 to the electric valve drive device 2.

  Similarly, when a frequency method is used for transmission of a response signal from the motor-operated valve driving device 2 to the control device 3, in the response period Ta, fully-open information indicating that the motor-operated valve 1 is in a fully-open state according to the frequency, A response signal is transmitted by a transmission signal SD2 expressed as fully closed information indicating that the valve 1 is in a fully closed state. That is, the frequency f21 in the fully open state (may be equal to f11) and the frequency f22 in the fully closed state (may be equal to f12) are different. The frequency corresponds to the on / off frequency of the transmission photocoupler 24S (light emitting diode LED21). The microcomputer 22 turns on / off the light emitting diode LED21 of the transmission photocoupler 24S with the transmission signal SD2 having the frequency f21 corresponding to the fully opened state, thereby transmitting a response signal indicating the fully opened state. Similarly, the microcomputer 22 turns on / off the light emitting diode LED21 of the transmission photocoupler 24S with the transmission signal SD2 having the frequency f22 corresponding to the fully closed state, thereby transmitting a response signal representing the fully closed state. The microcomputer 38 of the control device 3 monitors the reception signal RD1 input from the reception photocoupler 34R, and measures its frequency (the on / off frequency of the phototransistor PTR12), so that it is in a fully closed state and a fully open state. Detected separately. In this way, response signals representing the fully open state and the fully closed state can be transmitted from the motor-operated valve drive device 2 to the control device 3.

  In the pulse number method shown in FIG. 6 (d), in the command period Tc, the command is given by the transmission signal SD1 expressing the open command for opening the motor-operated valve 1 and the close command for closing the motor-operated valve 1 according to the number of pulses. A signal is transmitted. That is, the number of pulses for the opening command is different from the number of pulses for the closing command. The number of pulses corresponds to the number of times the transmission photocoupler 34S (light emitting diode LED11) is turned on / off. The microcomputer 38 outputs a transmission signal SD1 for turning on / off the light emitting diode LED11 of the transmission photocoupler 34S for the number of times corresponding to the opening command, thereby transmitting the opening command. Similarly, the microcomputer 38 outputs a transmission signal SD1 for turning on / off the light emitting diode LED11 of the transmission photocoupler 34S for the number of times corresponding to the closing command, thereby transmitting the closing command. The microcomputer 22 of the electric valve drive device 2 monitors the reception signal RD2 input from the reception photocoupler 24R, and measures the number of pulses (the number of times the phototransistor PTR22 is turned on / off), thereby opening and closing the command. It is detected separately from the command. In this way, the opening command and the closing command can be transmitted from the control device 3 to the electric valve drive device 2.

  Similarly, when the pulse number method is used for transmission of the response signal from the motor-operated valve driving device 2 to the control device 3, fully-open information indicating that the motor-operated valve 1 is in a fully-open state according to the number of pulses in the response period Ta The response signal is transmitted by the transmission signal SD2 expressing the fully closed information indicating that the motor-operated valve 1 is in the fully closed state. That is, the number of pulses in the fully open state (may be equal to the number of pulses in the open command) is different from the number of pulses in the fully closed state (may be equal to the number of pulses in the close command). The number of pulses corresponds to the number of times the transmission photocoupler 24S (light emitting diode LED21) is turned on / off. The microcomputer 22 outputs a transmission signal SD2 for turning on / off the light emitting diode LED21 of the transmission photocoupler 24S for the number of times corresponding to the fully opened state, thereby transmitting a response signal indicating the fully opened state. Similarly, the microcomputer 22 outputs a transmission signal SD2 for turning on / off the light emitting diode LED21 of the transmission photocoupler 24S for the number of times corresponding to the fully closed state, thereby transmitting a response signal representing the fully closed state. . The microcomputer 38 of the control device 3 monitors the reception signal RD1 input from the reception photocoupler 34R, and measures the number of pulses (the number of times the phototransistor PTR12 is turned on / off), whereby the fully closed state and the fully open state are detected. Detected separately. In this way, response signals representing the fully open state and the fully closed state can be transmitted from the motor-operated valve drive device 2 to the control device 3.

  In the pulse timing method shown in FIG. 6 (e), a transmission expressing an opening command for opening the motor-operated valve 1 and a closing command for closing the motor-operated valve 1 at the timing of generating a pulse within the command period Tc. A command signal is transmitted by the signal SD1. That is, the pulse generation timing of the opening command is different from the pulse generation timing of the closing command. For example, the microcomputer 38 transmits the transmission signal SD1 for returning the light emitting diode LED11 of the transmission photocoupler 34S to the off state for a predetermined time and returning it to the on state at the timing td11 when the time corresponding to the opening command has elapsed from the start of the command period Tc. Output, thereby sending an open command. Similarly, the microcomputer 38 transmits the light-emitting diode LED11 of the transmission photocoupler 34S by turning it off for a predetermined time and returning it to the on state at a timing td12 when the time corresponding to the closing command has elapsed from the start of the command period Tc. Is output, thereby sending a close command. In the example of FIG. 6E, the pulse generation timing td11 for the opening command is set in the first half of the command period Tc, and the pulse generation timing td12 for the closing command is set in the second half of the command period Tc. ing.

  The microcomputer 22 of the electric valve driving device 2 monitors the reception signal RD2 input from the reception photocoupler 24R, and receives a pulse reception timing within the command period Tc (for example, from the start of the command period Tc until a pulse is detected). By measuring the time), the open command and the close command are distinguished and detected. In this way, the opening command and the closing command can be transmitted from the control device 3 to the electric valve drive device 2.

  Similarly, when a pulse timing method is used for transmission of a response signal from the motor-operated valve driving device 2 to the control device 3, the motor-operated valve 1 is in a fully opened state depending on the timing of generating a pulse within the response period Ta. The response signal is transmitted by the transmission signal SD2 expressing the fully open information that represents the fully closed information that represents that the motor-operated valve 1 is in the fully closed state. That is, the pulse generation timing in the fully open state is different from the pulse generation timing in the fully closed state. For example, the microcomputer 22 generates a transmission signal SD2 for returning the light emitting diode LED21 of the transmission photocoupler 24S to the off state for a predetermined time at the timing td21 when the time corresponding to the fully opened state has elapsed from the start of the response period Ta. To output a response signal indicating the fully open state. Similarly, the microcomputer 22 transmits the light-emitting diode LED21 of the transmission photocoupler 24S to the off state for a predetermined time and returns it to the on state at the timing td22 when the time corresponding to the fully closed state has elapsed from the start of the response period Ta. SD2 is output, thereby transmitting a response signal indicating the fully closed state. In the example of FIG. 6E, the pulse generation timing td21 for the fully open state is set in the first half of the response period Ta, and the pulse generation timing td22 for the fully closed state is set in the second half of the response period Ta. Has been.

  The microcomputer 38 of the control device 3 monitors the reception signal RD1 input from the reception photocoupler 34R, and receives the pulse within the response period Ta (for example, the time from the start of the response period Ta until the pulse is detected). Is measured to distinguish between the fully closed state and the fully open state. In this way, response signals representing the fully open state and the fully closed state can be transmitted from the motor-operated valve drive device 2 to the control device 3.

  In the pulse interval method shown in FIG. 6 (f), a pair of pulses is generated in the command period Tc, and an open command for opening the motor-operated valve 1 and a motor-operated valve 1 are closed according to the interval between the pair of pulses. The command signal is transmitted by the transmission signal SD1 expressing the close command. That is, the pulse interval i11 of the opening command is different from the pulse interval i12 of the closing command. For example, the microcomputer 38 outputs the transmission signal SD1 for generating the first pulse by turning the light emitting diode LED11 of the transmission photocoupler 34S off for a predetermined time and returning it to the on state. The microcomputer 38 waits for the pulse interval i11 of the opening command, and then turns off the light emitting diode LED11 of the transmission photocoupler 34S for a predetermined time to return it to the on state, thereby generating a second pulse. The transmission signal SD1 is output. Thereby, an open command expressed by a pair of pulses opened by the pulse interval i11 is transmitted. Similarly, the microcomputer 38 outputs the transmission signal SD1 for returning the light emitting diode LED11 of the transmission photocoupler 34S to the ON state for a predetermined time, thereby generating the first pulse. The microcomputer 38 waits for the pulse interval i12 of the close command, and then outputs a transmission signal SD1 for turning the light emitting diode LED11 of the transmission photocoupler 34S off for a predetermined time and returning it to the on state. Generate the second pulse. Thereby, a close command expressed by a pair of pulses opened by a pulse interval i12 is transmitted.

  The microcomputer 22 of the electric valve driving device 2 monitors the reception signal RD2 input from the reception photocoupler 24R and receives a time interval between a pair of pulses received within the command period Tc (for example, the phototransistor PTR22 is turned off twice). By measuring the (or the time interval of turning on), the open command and the close command are distinguished and detected. In this way, the opening command and the closing command can be transmitted from the control device 3 to the electric valve drive device 2.

  Similarly, when a pulse interval method is used for transmission of a response signal from the electric valve driving device 2 to the control device 3, a pair of pulses is generated in the response period Ta. Then, by the transmission signal SD2 expressing the fully-open information indicating that the motor-operated valve 1 is in the fully-open state and the fully-closed information indicating that the motor-operated valve 1 is in the fully-closed state by the interval between the pair of pulses, the response A signal is transmitted. That is, the pulse interval i21 in the fully open state is different from the pulse interval i22 in the fully closed state. For example, the microcomputer 22 generates the first pulse by outputting the transmission signal SD2 for turning the light emitting diode LED21 of the transmission photocoupler 24S off for a predetermined time and returning it to the on state. Then, after waiting for the pulse interval i21 corresponding to the fully opened state, the microcomputer 22 outputs a transmission signal SD2 for turning the light emitting diode LED21 of the transmission photocoupler 24S off for a predetermined time and returning it to the on state. A second pulse is generated. Thereby, a response signal expressing the fully opened state is transmitted by a pair of pulses opened by the pulse interval i21. Similarly, the microcomputer 22 outputs the transmission signal SD2 for turning the light emitting diode LED21 of the transmission photocoupler 24S off for a predetermined time and returning it to the on state, thereby generating the first pulse. Then, after waiting for the pulse interval i22 corresponding to the fully closed state, the microcomputer 22 outputs the transmission signal SD2 for turning the light emitting diode LED21 of the transmission photocoupler 24S off for a predetermined time and returning it to the on state. To generate a second pulse. Thereby, a response signal expressing the fully closed state is transmitted by a pair of pulses opened by the pulse interval i22.

  The microcomputer 38 of the control device 3 monitors the reception signal RD1 signal input from the reception photocoupler 34R and receives a time interval between a pair of pulses received within the response period Ta (for example, the phototransistor PTR12 is turned off twice ( Alternatively, the fully-closed state and the fully-open state are distinguished from each other by measuring the interval of the time at which they are turned on. In this way, response signals representing the fully open state and the fully closed state can be transmitted from the motor-operated valve drive device 2 to the control device 3.

  In the serial data communication method shown in FIG. 6 (g), in the command period Tc, the serial signal is used to transmit an open command for opening the motor-operated valve 1 and a transmission signal SD1 expressing a close command for closing the motor-operated valve 1. A command signal is transmitted. That is, the serial data of the opening command is different from the serial data of the closing command. The microcomputer 38 outputs a transmission signal SD1 for turning on / off the light emitting diode LED11 of the transmission photocoupler 34S in a time-series pattern corresponding to the serial data of the opening command, thereby transmitting the opening command. Similarly, the microcomputer 38 outputs a transmission signal SD1 for turning on / off the light-emitting diode LED11 of the transmission photocoupler 34S in a time-series pattern according to the serial data of the closing command, thereby transmitting the closing command. To do. The microcomputer 22 of the electric valve driving device 2 monitors the reception signal RD2 input from the reception photocoupler 24R, and detects the time series pattern (the time series pattern of on / off of the phototransistor PTR22) to detect the serial signal. Data is decoded, and an open command and a close command are distinguished and detected. In this way, the opening command and the closing command can be transmitted from the control device 3 to the electric valve drive device 2.

  Similarly, when a serial data communication method is used for transmission of a response signal from the motor-operated valve driving device 2 to the control device 3, fully-open information indicating that the motor-operated valve 1 is in a fully-open state by serial data in the response period Ta. And a response signal is transmitted by a transmission signal SD2 expressing the fully closed information indicating that the motor-operated valve 1 is in the fully closed state. That is, serial data in the fully open state is different from serial data in the fully closed state. The microcomputer 22 outputs a transmission signal SD2 for turning on / off the light emitting diode LED21 of the transmission photocoupler 24S in a time-series pattern corresponding to serial data representing the fully opened state, and thereby a response signal representing the fully opened state Send. Similarly, the microcomputer 22 outputs a transmission signal SD2 for turning on / off the light emitting diode LED21 of the transmission photocoupler 24S in a time series pattern corresponding to the serial data representing the fully closed state, and thereby the fully closed state. A response signal indicating the state is transmitted. The microcomputer 38 of the control device 3 monitors the received signal RD1 input from the receiving photocoupler 34R, and detects serial data by detecting the time series pattern (time series pattern of on / off of the phototransistor PTR12). Decoding is performed to distinguish between the fully closed state and the fully open state. In this way, response signals representing the fully open state and the fully closed state can be transmitted from the motor-operated valve drive device 2 to the control device 3.

Note that the communication method used for transmission / reception of the command signal and the communication method used for transmission / reception of the response signal may be the same or different. For example, the command signal may be transmitted / received by the pulse width method, while the response signal may be transmitted / received by the frequency method. In addition, the above communication methods can be arbitrarily combined.
FIG. 7 is a flowchart for explaining an example of processing executed by the microcomputer 38 of the control device 3. When the electric valve control system 101 is turned on and the microcomputer 38 starts processing, the microcomputer 38 executes initial setting (step S1). The initial settings are a process for initializing timers TMR0 and TMR1 to zero, a process for initializing a fully open flag OPEN indicating the fully open state of the motor-operated valve 1, and a fully closed flag indicating a fully closed state of the motor-operated valve 1. The process includes a process for initializing CLOSE to 0, a process for initializing an error flag ERROR indicating occurrence of an abnormality to 0, and a process for turning off the indicators L1, L2, and L3. The timer TMR0 is a timer for measuring the interval T1. The timer TMR1 is a timer for measuring the time within the communication period T2.

  After the initial setting (step S1), the microcomputer 38 controls the power supply switching unit 33 to connect the first DC power supply 31 to the power lines 5A and 5B (step S2). Further, the microcomputer 38 outputs a transmission signal SD1 for holding the light emitting diode LED11 of the transmission photocoupler 34S in a light emitting state. The microcomputer 38 determines whether or not the time measured by the timer TMR0 has reached the interval T1 (step S3). If not, the microcomputer 38 increments the value of the timer TMR0 by +1 (step S4) and determines whether the interval T1 has elapsed. Wait (step S3).

When the time measured by the timer TMR0 reaches the interval T1 (step S3: YES), the microcomputer 38 controls the power supply switching unit 33 to switch to the second DC power supply 32 (step S5). Are connected to the power lines 5A and 5B.
The microcomputer 38 monitors the input from the reception photocoupler 34R and determines whether the start timing of the communication period T2 has arrived (step S6). When the start timing of the communication period T2 comes (step S6: YES), the microcomputer 38 resets the timer TMR1 to 0 (step S7). When the communication period T2 has already started (step S6: NO), the microcomputer 38 increments the value of the timer TMR1 by +1 (step S8). The subsequent processing branches according to the value of the timer TMR1 (step S9).

  Specifically, when the value of the timer TMR1 is t0 (for example, t0 = 0) or more and less than t1, a command signal output process (step S10) is executed. t1 is set in advance to a value corresponding to the length of the command period Tc. Therefore, the command signal output process is executed in the command period Tc (t0 ≦ TMR1 <t1) within the communication period T2. When the value of timer TMR1 is not less than t1 and less than t2, a response signal reception process (step S11) is executed. t2 is set to a value corresponding to the length of the communication period T2. Therefore, the response signal reception process is executed in the response period Ta (t1 ≦ TMR1 <t2) within the communication period T2. When the value of the timer TMR1 is other than that, no processing is performed (step S12).

Thereafter, the microcomputer 38 repeats the processing from step S6 while the value of the timer TMR1 is less than t2 (step S13: NO).
On the other hand, when the value of the timer TMR1 becomes t2 or more (step S13: YES), the microcomputer 38 executes an error detection process (step S14) and a state output process (step S15). The error detection process is a process of monitoring the time from the output of the command signal until the response signal indicating the operation of the motor-operated valve 1 corresponding thereto is received, and detecting the presence or absence of an abnormality. The state output process is a process for controlling the fully open indicator L1, the fully closed indicator L2, and the abnormality indicator L3 to output the state of the motor-operated valve 1 and the presence or absence of abnormality.

  Thereafter, the microcomputer 38 resets the timer TMR0 for measuring the interval T1 to 0 (step S16) and returns to step S2. Thereby, the microcomputer 38 controls the power supply switching unit 33 to switch from the second DC power supply 32 to the first DC power supply 31, and controls the light emitting diode LED11 of the transmission photocoupler 34S to be always lit. Accordingly, positive DC power from the first DC power supply 31 is supplied to the power lines 5A and 5B.

  FIG. 8 is a flowchart for explaining a specific example of the command signal output process (step S10). The microcomputer 38 confirms the input from the open / close command switch 36 (step S21), and if there is no input, ends the processing. When an open command is input from the open / close command switch 36, a command signal representing the open command is output (step S22). That is, the microcomputer 38 generates the transmission signal SD1 corresponding to the pulse width, frequency, number of pulses, pulse generation timing, pulse interval, or serial data (see FIG. 6) corresponding to the opening command, and thereby the transmission photo The light emitting diode LED11 of the coupler 34S is driven. When a close command is input from the open / close command switch 36, a close command signal is output. That is, the microcomputer 38 generates the transmission signal SD1 corresponding to the pulse width, frequency, number of pulses, pulse generation timing, pulse interval, or serial data (see FIG. 6) corresponding to the close command, and thereby the transmission photo The light emitting diode LED11 of the coupler 34S is driven.

  FIG. 9 is a flowchart for explaining a specific example of the response signal reception process (step S11). The microcomputer 38 monitors the reception signal RD1 input from the reception photocoupler 34R, and determines whether or not a response signal has been received (step S31). If no response signal is received (step S31: NO), the process is terminated. When the response signal is received (step S31: YES), the content of the received response signal is interpreted (step S32). This interpretation follows the method of the response signal sent out by the motor-operated valve driving device 2 (see FIG. 6). If the response signal indicates the fully open state, the microcomputer 38 sets a fully open flag OPEN indicating that the motor-operated valve 1 is in the fully open state (step S33). The response signal indicates the fully closed state. If so, the microcomputer 38 sets a fully closed flag CLOSE indicating that the motor-operated valve 1 is in the fully closed state to 1 (step S34). If it is interpreted that the response signal does not represent the fully open state or the fully closed state, the microcomputer 38 resets the flags OPEN and CLOSE to 0 (step S35). This represents that the motor-operated valve 1 is not in a fully closed state or in a fully open state, but is in an intermediate opening state, that is, a state in the middle of opening / closing switching.

FIG. 10 is a flowchart for explaining a specific example of the error detection process (step S14). When the value of the timer TMR1 reaches t2 and the communication period T2 ends (step S13: YES in FIG. 7), the microcomputer 38 executes an error detection process (step S14). The error detection state is updated every interval T1.
The microcomputer 38 monitors the response time from the output of the command signal indicating the open command in the command signal output process (step S10) until the response signal indicating the fully open state is received in the response signal reception process (step S11). (Step S41). Similarly, the microcomputer 38 responds until the response signal indicating the fully closed state is received in the response signal receiving process (step S1) after the command signal indicating the close instruction is output in the command signal output process (step S10). The time is monitored (step S41). If these response times exceed the predetermined time, the microcomputer 38 determines that the time is over (step S42: YES), and sets an error flag ERROR indicating the occurrence of abnormality to 1 (step S43). If the time is not over (step S42: NO), the process ends without setting the error flag ERROR.

  FIG. 11 is a flowchart for explaining a specific example of the state output process (step S15). When the value of the timer TMR1 reaches t2 and the communication period T2 ends (step S13 in FIG. 7: YES), the microcomputer 38 performs a state output process (step S13) for updating the display states of the indicators L1, L2, and L3. S15) is executed. That is, the display states of the display devices L1, L2, and L3 are updated every time one communication period T2 ends, and thus are updated every interval T1.

  If the full open flag OPEN is 1 (step S51: YES), the microcomputer 38 turns on the full open indicator L1 (step S52), otherwise turns off the full open indicator L1 (step S53). If the fully closed flag CLOSE is 1 (step S54: YES), the microcomputer 38 turns on the fully closed display L2 (step S55), otherwise turns off the fully closed display L2 (step S55). S56). Further, if the error flag ERROR is 1 (step S57: YES), the microcomputer 38 turns on the abnormality indicator L3 (step S58), otherwise ends the process. Accordingly, the indicators L1 and L2 are turned on / off according to the values of the flags OPEN and CLOSE, and when the error flag ERROR is set to 1, the abnormality indicator L3 is held in the error display state. Thereby, whether or not the motor-operated valve 1 is fully opened, whether or not the motor-operated valve 1 is fully closed, and whether or not an abnormality has occurred are displayed, and information corresponding to the user is notified by the display.

  FIG. 12 is a flowchart for explaining a specific example of processing by the microcomputer 22 of the electric valve driving device 2. When electric power is supplied from the power lines 5A and 5B to the motor-operated valve driving device 2, thereby the microcomputer 22 starts processing, the microcomputer 22 executes initial setting (step S61). The initial setting includes a process for initializing the timer TMR2 to 0, a process for stopping the electric motor 20, a process for initializing an open command flag OPEN indicating that an open command has been given, and a close command Including a process of initializing a close command flag CLOSE indicating that the The timer TMR2 is a timer for measuring the time within the communication period T2. Further, the microcomputer 22 outputs a transmission signal SD2 for holding the light emitting diode LED21 of the transmission photocoupler 24S in a light emitting state.

  After the initial setting, the microcomputer 22 monitors the input from the reception photocoupler 24R and determines whether the start timing of the communication period T2 has arrived (step S62). When the start timing of the communication period T2 comes (step S62: YES), the microcomputer 22 resets the timer TMR2 to 0 (step S63). When the communication period T2 has already started (step S62: NO), the microcomputer 22 increments the value of the timer TMR2 by +1 (step S64). The subsequent processing branches according to the value of the timer TMR2 (step S65).

  Specifically, when the value of the timer TMR2 is equal to or greater than t0 (for example, t0 = 0) and less than t1, a command signal reception process (step S66) is executed. t1 is set in advance to a value corresponding to the length of the command period Tc. Therefore, the command signal reception process is executed in the command period Tc (t0 ≦ TMR2 <t1) within the communication period T2. When the value of timer TMR2 is not less than t1 and less than t2, a response signal transmission process (step S67) is executed. t2 is set to a value corresponding to the length of the communication period T2. Therefore, the response signal transmission process is executed in the response period Ta (t1 ≦ TMR2 <t2) within the communication period T2. When the value of the timer TMR2 is other than that, no processing is performed (step S68).

Thereafter, the microcomputer 22 repeats the processing from step S62 while the value of the timer TMR2 is less than t2 (step S69: NO).
On the other hand, when the value of the timer TMR2 reaches t2 (step S69: YES), the microcomputer 22 executes a motor control process (step S70) for controlling the driving of the electric motor 20.

Thereafter, the microcomputer 22 returns to step S62 and repeats the process.
FIG. 13 is a flowchart for explaining a specific example of the command signal reception process (step S66). The microcomputer 22 monitors the reception signal RD2 input from the phototransistor PTR22 of the reception photocoupler 24R, and checks for the presence of a command signal (step S71). If no command signal is received (step S71: NO), the microcomputer 22 resets both the open command flag OPEN and the close command flag CLOSE to 0 (step S75), and ends the process.

  When the command signal is received (step S71: YES), the microcomputer 22 interprets the content of the received command signal (step S72). If the command signal represents an open command, the microcomputer 22 sets the open command flag OPEN to 1 (step S73) and ends the process. If the command signal represents a close command, the microcomputer 22 sets the close command flag CLOSE to 1 (step S74) and ends the process. If the command signal is not interpreted as either an open command or a close command, the microcomputer 22 resets both the open command flag OPEN and the close command flag CLOSE to 0 (step S75), and ends the process.

  The interpretation of the command signal follows the method of the command signal sent out by the control device 3. That is, when a command signal of pulse width, frequency, number of pulses, pulse reception timing, pulse interval or serial data (see FIG. 6) corresponding to the open command is received, the microcomputer 22 interprets that the open command has been received. To do. Similarly, when a command signal of pulse width, frequency, number of pulses, pulse reception timing, pulse interval or serial data (see FIG. 6) corresponding to the close command is received, the microcomputer 22 receives the close command. Interpret.

  FIG. 14 is a flowchart for explaining a specific example of the response signal transmission process (step S67). The microcomputer 22 confirms the input signal from the full open detection switch LS1 and the input signal from the full close detection switch LS2 (step S81), and determines the valve position of the motor operated valve 1 based on the input signal (step S82). If the fully open detection switch LS1 is in the on state, the microcomputer 22 determines that the valve position of the motor-operated valve 1 is the fully open position, and outputs a response signal indicating the fully open state (step S83). If the fully closed detection switch LS2 is in the on state, the microcomputer 22 determines that the valve position of the motor-operated valve 1 is in the fully closed position, and outputs a response signal indicating the fully closed state (step S84). If both the full open detection switch LS1 and the full close detection switch LS2 are in the OFF state, the microcomputer 22 determines that the opening degree is intermediate and does not output a response signal.

  The microcomputer 22 outputs a response signal by performing on / off control of the light emitting diode LED21 of the transmission photocoupler 24S according to the content of the response signal (fully opened state or fully closed state). The format of the response signal follows a predetermined communication method. That is, the microcomputer 22 sets the pulse width, frequency, number of pulses, pulse generation timing, pulse interval, or serial data (see FIG. 6) according to the fully open state or the fully closed state, and accordingly, the transmission photo A transmission signal SD2 for on / off control of the light emitting diode LED21 of the coupler 24S is generated.

  FIG. 15 is a flowchart for explaining a specific example of the motor control process (step S70). In the microcomputer 22, the open command flag OPEN is 1 (step S91: YES), and the fully open detection switch LS1 does not generate a fully open output, that is, the valve position is not fully open (step S92: NO). Then, a drive signal for driving the electric motor 20 in the forward rotation direction (opening direction) is input to the motor drive circuit 21 (step S93). Thereby, electric power is supplied to the electric motor 20, the electric motor 20 rotates in the opening direction, and the electric valve 1 is closed. When the motor-operated valve 1 reaches the fully-open position, the fully-open detection switch LS1 generates a fully-open output (step S92: YES), so that driving of the electric motor 20 in the opening direction is stopped.

  On the other hand, the microcomputer 22 indicates that the close command flag CLOSE is 1 (step S94: YES) and the fully closed detection switch LS2 does not generate a fully closed output, that is, the valve position is not the fully closed position. (Step S95: NO), a drive signal for driving the electric motor 20 in the reverse rotation direction (closing direction) is input to the motor drive circuit 21 (Step S96). Thereby, electric power is supplied to the electric motor 20, the electric motor 20 rotates in the closing direction, and the electric valve 1 is opened. When the motor-operated valve 1 reaches the fully-closed position, the fully-closed detection switch LS2 generates a fully-closed output (step S95: YES), so that driving of the electric motor 20 in the closing direction is stopped.

Thus, the motor-operated valve 1 can be controlled to the fully open state or the fully closed state according to the values of the open command flag OPEN and the close command flag CLOSE.
As described above, according to this embodiment, communication between the control device 3 and the electric valve drive device 2 can be achieved using the power lines 5A and 5B. Wiring of signal lines for communication between them is not necessary. As a result, the number of wires can be reduced, and a configuration for avoiding interference between the power line and the signal line can be omitted. Therefore, the configuration of the wiring becomes simple, the wiring material cost can be reduced accordingly, and the wiring work can be reduced, so that the cost can be greatly reduced. Also, when the wiring is housed in the pipe, the pipe diameter can be reduced, or a configuration for avoiding signal interference in the pipe can be omitted, so that a significant cost reduction can be achieved.

  Furthermore, since the signal path is transmitted by turning on / off the current path, it is hardly affected by the wiring length between the control device 3 and the motor-operated valve driving device 2, and therefore, long-distance communication is possible. is there. That is, the present invention can also be applied to an application in which the control device 3 and the electric valve drive device 2 are arranged far apart. Further, since the current path is turned on / off, the speed (frequency) of the signal can be reduced as compared with the case where the signal is superimposed on the power lines 5A and 5B by a coil or a capacitor. Therefore, inexpensive photocouplers 34S, 34R, 24S, and 24R can be applied for signal transmission and reception. As a result, the cost can be reduced.

  Further, the DC power source connected to the power lines 5A and 5B is switched from the first DC power source 31 to the second DC power source 32 at a constant interval T1, and the second DC power source 32 is connected to the power lines 5A and 5B for a predetermined time. Later, the first DC power supply 31 is switched again. Thereby, since communication between the control device 3 and the electric valve drive device 2 can be performed at a constant interval T1, it is possible to perform periodic communication.

  Further, according to the configuration of this embodiment, when the first DC power supply 31 is connected to the power lines 5A and 5B and DC power having the first polarity is supplied to the power lines 5A and 5B, the first DC power supply 31 Is passed through the Schottky diode 25 on the electric valve driving device 2 side and the Schottky diode 35 on the control device 3 side. Therefore, regardless of the operation of the transmission photocoupler 34S on the control device 3 side and the transmission photocoupler 24S on the electric valve drive device 2 side, the current path passing through the power lines 5A and 5B is in a conductive state, and the electric motor 20 Is supplied with stable power.

In this embodiment, the current path formed when the second DC power supply 32 is connected to the power lines 5A and 5B forms a current loop that is not easily affected by the wiring length. This is an advantageous configuration.
Further, according to this embodiment, since the diode bridge 27 is connected to the power lines 5A and 5B, the second DC power supply 32 is connected to the power lines 5A and 5B, and negative DC power is supplied to the power lines 5A and 5B. Even when being supplied, the rectified power can be supplied to the motor drive circuit 21. Therefore, even when the second DC power supply 32 is connected to the power lines 5A and 5B, it is possible to supply power to the electric motor 20 as long as the current path passing through the power lines 5A and 5B is closed. As a result, communication between the control device 3 and the motor-operated valve driving device 2 can be realized using the power lines 5A and 5B without greatly affecting the operation of the motor-operated valve 1. In the control of fully opening or closing the motor-operated valve 1, it is within an allowable range that the operating speed of the motor-operated valve 1 slightly varies when the second DC power source 32 is switched.

  The period in which the second DC power supply 32 is connected to the power lines 5A and 5B is a period for communication, and communication using the power lines 5A and 5B is performed by opening and closing the current path passing through the power lines 5A and 5B. Is done. Therefore, a route passing through the power lines 5A and 5B may open. At this time, the power supply from the control device 3 is interrupted. Therefore, in this embodiment, the power supply unit 23 provided in the electric valve driving device 2 includes a capacitor C. When the power supply from the control device 3 side is interrupted, the electric power stored in the capacitor C is supplied to the motor drive circuit 21, whereby the drive of the electric motor 20 can be continued. Thereby, the influence on the operation | movement of the motor operated valve 1 by communication using power line 5A, 5B can be reduced further.

Further, according to this embodiment, a command signal can be transmitted from the control device 3 to the motor-operated valve driving device 2 by communication using the power lines 5A and 5B, and a response signal ( A signal indicating the state of the motor-operated valve 1) can be transmitted. Thus, the motor-operated valve 1 can be remotely controlled from the control device 3 while monitoring the state of the motor-operated valve 1.
Furthermore, according to this embodiment, the period during which the second DC power supply 32 is connected to the power lines 5A, 5B is defined as the communication period T2, and the communication period T2 is divided into the command period Tc and the response period Ta. Yes. Therefore, communication via the power lines 5A and 5B between the control device 3 and the electric valve drive device 2 can be realized while avoiding interference between the command signal and the response signal.

  According to this embodiment, the control device 3 can give an open command for opening the motor-operated valve 1 and a close command for closing the motor-operated valve 1 to the motor-operated valve driving device 2. Thereby, opening / closing control of the electric valve 1 can be performed. A response signal indicating the fully open state of the motor operated valve 1 and the fully closed state of the motor operated valve 1 is sent from the motor operated valve driving device 2 to the control device 3. Thereby, the control apparatus 3 can monitor the open / close state of the motor-operated valve 1.

  FIG. 16 is a block diagram for explaining a configuration of an electric valve control system according to the second embodiment of the present invention. In FIG. 16, the corresponding parts of the parts shown in FIG. The motor-operated valve control system 101 according to the first embodiment is configured to control the motor-operated valve 1 to be fully open or fully closed, whereas the motor-operated valve control system 102 according to the second embodiment is a motor-operated valve. 1 is controlled to an arbitrary opening between fully open and fully closed.

The motor-operated valve control system 102 supplies a motor-driven valve drive device 2 for driving the motor-operated valve 1, a control device 3 for controlling the motor-driven valve drive device 2, and DC power from the control device 3 to the motor-driven valve drive device 2. A pair of first power line 5A and second power line 5B.
The motor-operated valve 1 is interposed in a pipe 6 through which a fluid flows, and adjusts the opening degree of the flow path of the pipe 6. The electric valve driving device 2 is mechanically coupled to the electric valve 1 and has an electric motor 20 (DC motor) as an electric actuator for driving the electric valve 1. On the other hand, the control apparatus 3 is arrange | positioned in the place away from the motor operated valve 1, and supplies direct-current power to the motor operated valve drive apparatus 2 via power line 5A, 5B. For example, a plurality of motor-operated valve driving devices 2 are provided corresponding to a plurality of motor-operated valves 1 respectively disposed at a plurality of locations, and the plurality of motor-operated valve driving devices 2 are concentrated by one control device 3. May be controlled automatically.

The electric valve driving device 2 includes an electric motor 20, a motor driving circuit 21 that supplies electric power to the electric motor 20, and a microcomputer 22 that controls the motor driving circuit 21. The electric valve driving device 2 further includes a power supply unit 23, a regulator 26, and a signal transmission / reception circuit 24. The power supply unit 23 includes a diode bridge 27 connected to the power lines 5 </ b> A and 5 </ b> B, and a parallel circuit of a resistor R <b> 2 and a capacitor C connected to the output side of the diode bridge 27, and the motor drive to be supplied to the motor drive circuit 21. to generate a voltage _{V M.} The regulator 26 is connected in parallel to the capacitor C on the output side of the diode bridge 27. The signal transmission / reception circuit 24 is interposed between the diode bridge 27 and the first power line 5A. The diode bridge 27 is a rectifier circuit that rectifies and outputs power supplied to the power lines 5A and 5B. The capacitor C stores electric power derived from the power supply line on the output side of the diode bridge 27. A motor drive circuit 21 is connected to the capacitor C. The regulator 26 generates a control voltage V _CC2 (for example, 5 V).

  The electric valve driving device 2 further includes an opening degree detection unit 52 that detects the opening degree of the electric valve 1. The opening degree detection unit 52 can be configured by, for example, a potentiometer that detects the position of any movable member in the driving force transmission path 28 from the electric motor 20 to the electric valve 1. The opening signal output from the opening detection unit 52 is input to an analog / digital (A / D) conversion port of the microcomputer 22. The electrically operated valve drive device 2 further includes a fully opened detection switch LS1 for detecting the fully opened state of the electrically operated valve 1 and a fully closed detection switch LS2 for detecting the fully closed state of the electrically operated valve 1. The full open detection switch LS1 and the full close detection switch LS2 are connected to the microcomputer 22 and notify the microcomputer 22 of full open and full close of the motor-operated valve 1, respectively. The full open detection switch LS1 and the full close detection switch LS2 are arranged so as to be operated by a movable member interlocked with the valve body of the electric valve 1 in the driving force transmission path 28 from the electric motor 20 to the electric valve 1. Whether or not the position of one valve body is a fully open position and a fully closed position is detected. The fully open detection switch LS1 can be configured by a limit switch that is conductive when the motor-operated valve 1 is fully open and is nonconductive when it is not fully open. Similarly, the fully-closed detection switch LS2 can be configured by a limit switch that is conductive when the motor-operated valve 1 is fully closed and is non-conductive when it is not fully closed.

The signal transmission / reception circuit 24 receives a command signal from the control device 3 via the power lines 5A and 5B and transmits it to the microcomputer 22 as a reception signal RD2. The signal transmission / reception circuit 24 receives the transmission signal SD2 representing the state of the motor-operated valve 1 from the microcomputer 22 and transmits the transmission signal to the control device 3 as a response signal via the power lines 5A and 5B. .
The control device 3 includes a DC power supply unit 30, a power supply switching unit 33, a signal transmission / reception circuit 34, and a microcomputer 38. The control device 3 further includes an opening degree command unit 51 connected to the microcomputer 38 and a display unit 53 connected to the microcomputer 38. The display unit 53 includes an opening degree indicator 54 that displays the opening degree of the motor-operated valve 1, an open / close indicator 55 that indicates whether the motor-operated valve 1 is fully opened / closed, and an abnormality indicator 56 that notifies the occurrence of an abnormality. Including.

The DC power supply unit 30 includes a first DC power supply 31 that generates a positive DC voltage V _DD (for example, + 24V) and a second DC power supply 32 that generates a negative DC voltage −V _EE (for example, −12V). In addition, it is configured to obtain electric power from the commercial AC power supply 4 and generate the DC voltages V _DD and -V _EE thereof. The absolute value of the voltage −V _EE generated by the second DC power supply 32 may be equal to or lower than the voltage V _DD generated by the first DC power supply 31.

The power supply switching unit 33 selectively connects the first DC power supply 31 or the second DC power supply 32 to the power lines 5A and 5B. Therefore, when the first DC power supply 31 is connected to the power lines 5A and 5B, DC power having the first polarity (positive polarity) is supplied to the power lines 5A and 5B, and the second DC power supply 32 is connected to the power lines 5A and 5B. Then, DC power of the second polarity (negative polarity) is supplied to the power lines 5A and 5B. The switching operation of the power supply switching unit 33 is controlled by a selection signal SEL given from the microcomputer 38. The DC voltage V _DD generated by the first DC power supply 31 is supplied to a regulator 39 provided in the control device 3, and the control voltage V _CC1 is generated by the regulator 39.

  A signal transmission / reception circuit 34 is interposed in the second power line 5B on the ground side. The signal transmission / reception circuit 34 receives the transmission signal SD1 from the microcomputer 38 and transmits the signal as a command signal to the motor-operated valve driving device 2 through the power lines 5A and 5B. Further, the signal transmission / reception circuit 34 receives the response signal from the electric valve driving device 2 via the power lines 5A and 5B, and passes the response signal to the microcomputer 38 as the reception signal RD1.

The opening degree command unit 51 is an operation unit that is operated by a user, and can be constituted by, for example, a variable resistor connected between the control voltage _VCC1 and the ground potential. The output signal of the opening command unit 51 is input to the A / D conversion port of the microcomputer 38 as an opening command. The microcomputer 38 transmits an opening degree command to the signal transmission / reception circuit 34, and the signal transmission / reception circuit 34 transmits a command signal representing the opening degree instruction to the motor-operated valve driving device 2 via the power lines 5A and 5B.

When the response signal from the electric valve driving device 2 is given from the signal transmission / reception circuit 34, the microcomputer 38 controls the display states of the opening indicator 54 and the open / close indicator 55 according to the contents. Further, the microcomputer 38 executes an abnormality detection process internally, and when an abnormality is detected, the abnormality indicator 56 notifies the abnormality.
Communication between the control device 3 and the electric valve drive device 2 is performed exclusively through the power lines 5A and 5B, and a dedicated signal line for transmitting and receiving the command signal and the response signal is provided between them. Not.

  The microcomputer 38 of the control device 3 monitors an input signal from the opening degree command unit 51, and in response to the opening degree command input from the opening degree command unit 51, the power lines 5 </ b> A and 5 </ b> B are transmitted from the signal transmission / reception circuit 34. Then, a command signal representing the opening degree command is transmitted to the motor-operated valve driving device 2. The microcomputer 22 of the electric valve driving device 2 receives a command signal representing an opening degree command from the power lines 5A and 5B via the signal transmission / reception circuit 24. Then, the microcomputer 22 of the electric valve drive device 2 inputs a normal rotation drive signal or a reverse rotation drive signal to the motor drive circuit 21.

  More specifically, the microcomputer 22 compares the command opening degree commanded by the opening degree command with the actual opening degree (detection opening degree) detected by the opening degree detection unit 52, and the command opening degree is actually opened. If it is greater than the degree, a forward drive signal is input to the motor drive circuit 21. Thereby, a drive current in the forward direction is supplied from the motor drive circuit 21 to the electric motor 20, and the electric motor 20 rotates in the forward direction accordingly. Thereby, the valve body of the motor-operated valve 1 is displaced in the opening direction. Thereby, when the actual opening detected by the opening detection unit 52 reaches the command opening, the microcomputer 22 stops the input of the forward drive signal to the motor drive circuit 21.

  On the other hand, if the command opening is smaller than the actual opening, the microcomputer 22 inputs a reverse drive signal to the motor drive circuit 21. As a result, a drive current in the reverse direction is supplied from the motor drive circuit 21 to the electric motor 20, and the electric motor 20 rotates in the reverse direction accordingly. Accordingly, when the actual opening detected by the opening detection unit 52 is reduced to the command opening, the microcomputer 22 stops inputting the reverse drive signal to the motor drive circuit 21.

The microcomputer 22 also transmits a response signal representing information on the actual opening detected by the opening detection unit 52 from the signal transmission receiving circuit 24 to the control device 3 through the power lines 5A and 5B.
In this way, the opening degree of the motor-operated valve 1 is controlled to the command opening degree according to the opening degree command (command signal) given from the control device 3 to the motor-operated valve driving device 2 through the power lines 5A and 5B. Can do. And the response signal showing the actual opening degree of the motor-operated valve 1 is notified from the motor-operated valve driving device 2 to the control device 3 through the power lines 5A and 5B.

Specific configuration examples of the power supply switching unit 33 and the signal transmission / reception circuits 34 and 24 are the same as those in the first embodiment. Moreover, the structure regarding the communication between the control apparatus 3 and the electrically driven valve drive apparatus 2 performed via power line 5A, 5B is the same as that of the case of 1st Embodiment. Therefore, referring to FIGS. 2 to 5 described above again, description thereof will be omitted.
FIG. 17 is a timing chart for explaining an example of transmission signals from the transmission photocouplers 34S and 24S. FIG. 17A shows a command period Tc and a response period Ta within the communication period T2. FIG. 17B shows communication (transmission signals SD1 and SD2) in the pulse width method. FIG. 17 (c) shows frequency-based communication (transmission signals SD1, SD2). FIG. 17 (d) shows communication (transmission signals SD1, SD2) using the pulse number method. FIG. 17 (e) shows communication (transmission signals SD1, SD2) using the pulse timing method. FIG. 17 (f) shows communication (transmission signals SD1, SD2) using the pulse interval method. FIG. 17 (g) shows communication by serial data communication (transmission signals SD1, SD2).

  In the pulse width method shown in FIG. 17B, the command signal is transmitted by the transmission signal SD1 expressing the command opening degree by the pulse width in the command period Tc. That is, a signal having a pulse width tw1 corresponding to the command opening is generated. The pulse width corresponds to the off time length or the on time length of the transmission photocoupler 34S (light emitting diode LED11). The microcomputer 38 outputs a transmission signal SD1 for holding the light emitting diode LED11 of the transmission photocoupler 34S in the on state or the off state for a time length corresponding to the command opening, thereby transmitting the command opening. The microcomputer 22 of the electric valve driving device 2 monitors the reception signal RD2 input from the reception photocoupler 24R, and its pulse width (the ON time length or the OFF time length of the phototransistor PTR22. Example of FIG. 17B). Then, the command opening is interpreted by measuring the on-time length). In this way, the command opening can be transmitted from the control device 3 to the electric valve drive device 2.

  Similarly, when the pulse width method is used for transmission of the response signal from the motor-operated valve driving device 2 to the control device 3, in the response period Ta, the transmission signal SD2 expressing the actual opening of the motor-operated valve 1 is represented by the pulse width. A response signal is transmitted. That is, a signal having a pulse width tw2 corresponding to the actual opening is generated. The pulse width corresponds to the off time length or the on time length of the transmission photocoupler 24S (light emitting diode LED21) (on time length in the example of FIG. 17B). The microcomputer 22 outputs a transmission signal SD2 for holding the light emitting diode LED21 of the transmission photocoupler 24S in an on state or an off state for a length of time corresponding to the actual opening, thereby generating a response signal representing the actual opening. Send. The microcomputer 38 of the control device 3 monitors the input signal from the receiving photocoupler 34R, and its pulse width (the ON time length or the OFF time length of the phototransistor PTR12. The ON time length in the example of FIG. 17B). The actual opening is interpreted by measuring. Thus, the actual opening degree of the motor-operated valve 1 can be transmitted from the motor-operated valve driving device 2 to the control device 3.

  In the frequency method shown in FIG. 17 (c), in the command period Tc, the command signal is transmitted by the transmission signal SD1 expressing the command opening degree by the frequency. That is, a transmission signal SD1 having a frequency f1 corresponding to the command opening is generated. The frequency corresponds to the on / off frequency of the transmission photocoupler 34S (light emitting diode LED11). The microcomputer 38 turns on / off the light emitting diode LED11 of the transmission photocoupler 34S with the transmission signal SD1 having the frequency f1 corresponding to the command opening, thereby transmitting the command opening. The microcomputer 22 of the electric valve driving device 2 interprets the command opening by monitoring the reception signal RD2 input from the reception photocoupler 24R and measuring the frequency (the on / off frequency of the phototransistor PTR22). To do. In this way, the command opening can be transmitted from the control device 3 to the electric valve drive device 2.

  Similarly, when a frequency system is used for transmission of a response signal from the motor-operated valve driving device 2 to the control device 3, the response signal is represented by a transmission signal SD2 that represents the actual opening of the motor-operated valve 1 by frequency in the response period Ta. Is sent. That is, a transmission signal SD2 having a frequency f2 corresponding to the actual opening of the motor-operated valve 1 is generated. The frequency f2 corresponds to the transmission photocoupler 24S (the frequency at which the light emitting diode LED21 is turned on / off. The microcomputer 22 turns the light emitting diode LED21 of the transmission photocoupler 24S on / off at the frequency f2 corresponding to the actual opening. Accordingly, the microcomputer 38 of the control device 3 monitors the reception signal RD1 input from the reception photocoupler 24R and monitors the frequency (ON / OFF of the phototransistor PTR12). The actual opening is interpreted by measuring the off-frequency), so that the actual opening of the motor-operated valve 1 can be transmitted from the motor-operated valve driving device 2 to the control device 3.

  In the pulse number method shown in FIG. 17 (d), the command signal is transmitted by the transmission signal SD1 expressing the command opening by the number of pulses in the command period Tc. That is, the number of pulses corresponding to the command opening is generated. The number of pulses corresponds to the number of times the transmission photocoupler 34S (light emitting diode LED11) is turned on / off. The microcomputer 38 generates the transmission signal SD1 for turning on / off the light emitting diode LED11 of the transmission photocoupler 34S by the number of times corresponding to the command opening, thereby transmitting the command opening. The microcomputer 22 of the electric valve driving device 2 monitors the reception signal RD2 input from the reception photocoupler 24R, and measures the number of pulses (the number of times the phototransistor PTR22 is turned on / off), thereby determining the command opening. Interpret. In this way, the command opening can be transmitted from the control device 3 to the electric valve drive device 2.

  Similarly, when the pulse number method is used for transmission of the response signal from the motor-operated valve driving device 2 to the control device 3, the response is made by the transmission signal SD2 expressing the actual opening degree of the motor-operated valve 1 by the number of pulses in the response period Ta. A signal is transmitted. That is, the number of pulses corresponding to the actual opening of the motor-operated valve 1 is generated. The number of pulses corresponds to the number of times the transmission photocoupler 24S (light emitting diode LED21) is turned on / off. The microcomputer 22 turns on / off the light emitting diode LED21 of the transmission photocoupler 24S a number of times corresponding to the actual opening, thereby transmitting a response signal representing the actual opening. The microcomputer 38 of the control device 3 monitors the reception signal RD2 input from the reception photocoupler 34R, and interprets the actual opening by measuring the number of pulses (number of times the phototransistor PTR12 is turned on / off). . Thus, the actual opening degree of the motor-operated valve 1 can be transmitted from the motor-operated valve driving device 2 to the control device 3.

  In the pulse timing system shown in FIG. 17 (e), the command opening is expressed and transmitted by the timing of generating a pulse within the command period Tc. That is, a pulse is generated at a timing corresponding to the command opening. The microcomputer 38 generates a transmission signal SD1 for turning on and off the light emitting diode LED11 of the transmission photocoupler 34S for a predetermined time at a timing td1 according to the command opening, thereby Send. For example, the time length from the start of the command period Tc to the generation of the pulse corresponds to the command opening.

  The microcomputer 22 of the electric valve driving device 2 monitors the reception signal RD2 input from the reception photocoupler 24R, and receives a pulse reception timing within the command period Tc (for example, from the start of the command period Tc until a pulse is detected). The command opening is interpreted by measuring (time). In this way, the command opening can be transmitted from the control device 3 to the electric valve drive device 2.

  Similarly, when the pulse timing method is used for transmission of the response signal from the motor-operated valve driving device 2 to the control device 3, the actual opening of the motor-operated valve 1 is expressed by the timing of generating a pulse within the response period Ta. Sent. That is, a pulse is generated at a timing corresponding to the actual opening of the motor operated valve 1. The microcomputer 22 generates a transmission signal SD2 for turning on and off the light emitting diode LED21 of the transmission photocoupler 24S for a predetermined time at a timing td2 corresponding to the actual opening, thereby reducing the actual opening. The response signal that represents is transmitted. For example, the time length from the start of the response period Ta to the generation of the pulse corresponds to the actual opening.

  The microcomputer 38 of the control device 3 monitors the reception signal RD1 input from the reception photocoupler 34R, and receives the pulse within the response period Ta (for example, the time from the start of the response period Ta until the pulse is detected). The actual opening is interpreted by measuring. Thus, the actual opening degree of the motor-operated valve 1 can be transmitted from the motor-operated valve driving device 2 to the control device 3.

  In the pulse interval method shown in FIG. 17 (f), a pair of pulses is generated in the command period Tc, and the command signal is transmitted by the transmission signal SD1 expressing the command opening degree by the interval between the pair of pulses. That is, a transmission signal SD1 for generating a pair of pulses at an interval i1 corresponding to the command opening is output. The microcomputer 38 generates a first pulse by outputting a transmission signal SD1 that turns the light emitting diode LED1 of the transmission photocoupler 34S on for a predetermined time and returns it to the off state. The microcomputer 38 waits for a length of time corresponding to the command opening, and then outputs a transmission signal SD1 that turns on the light emitting diode LED11 of the transmission photocoupler 34S for a predetermined time and returns it to the off state. Generate the second pulse. Thereby, the command opening expressed by the time interval i1 of the pair of pulses is transmitted.

  The microcomputer 22 of the motor-driven valve driving device 2 monitors the reception signal RD2 input from the reception photocoupler 24R and receives a time interval between a pair of pulses received within the command period Tc (for example, the phototransistor PTR22 is turned on twice). The command opening is interpreted by measuring (or the interval of time when (or turned off)). In this way, the command opening can be transmitted from the control device 3 to the electric valve drive device 2.

  Similarly, when the pulse interval method is used for transmission of the response signal from the motor-driven valve driving device 2 to the control device 3, a pair of pulses is generated in the response period Ta, and the motor-operated valve is generated by the interval i2 between the pair of pulses. 1 actual opening is expressed and transmitted. That is, a transmission signal SD2 for generating a pair of i2 pulses is generated at intervals corresponding to the actual opening. The microcomputer 22 generates a first pulse by outputting a transmission signal SD2 that turns the light emitting diode LED21 of the transmission photocoupler 24S on for a predetermined time and returns it to the off state. The microcomputer 22 waits for a length of time corresponding to the command opening, and then outputs a transmission signal SD2 that turns on the light emitting diode LED21 of the transmission photocoupler 24S for a predetermined time and returns it to the off state. Generate the second pulse. Thereby, a response signal representing the actual opening expressed by the time interval i2 of the pair of pulses is transmitted.

  The microcomputer 38 of the control device 3 monitors the reception signal RD1 input from the reception photocoupler 34R and receives a time interval between a pair of pulses received within the response period Ta (for example, the phototransistor PTR12 is turned on twice (or The actual opening is interpreted by measuring the time interval). Thus, the actual opening degree of the motor-operated valve 1 can be transmitted from the motor-operated valve driving device 2 to the control device 3.

The expression of the opening value (command opening or actual opening) by the pulse intervals i1 and i2 will be described more specifically.
If the opening value 100% is expressed by a pulse interval TS (where TS <Tc, TS <Ta), an arbitrary opening value k (%) is a pulse interval twk proportional to the opening value k (%). Can be expressed as (twk / TS) × 100 (%).

However, when the opening value is 0%, the pulse interval Twk = 0, so that two pulses with a constant pulse width tw overlap and cannot be detected separately. The same applies when the pulse interval twk is less than or equal to the pulse width tw.
Therefore, an offset twz larger than the pulse width tw is introduced, and two pulses are generated at the offset pulse interval twk + twz. However, TS + twz <Tc and TS + twz <Ta. The offset pulse interval when the opening value is 0% is twz, and the offset pulse interval when the opening value is 100% is TS + twz.

The transmitting side generates a pair of pulses at the pulse interval twk + twz (= i1 or i2) determined in this way. The receiving side subtracts the offset twz from the detected pair of pulse intervals to obtain the pulse interval twk before the offset, and calculates the opening value = (twk / TS) × 100 (%) based on the pulse interval twk.
The aforementioned pulse timing method (FIG. 17 (e)) can be said to be a method in which the first pulse in the pulse interval method is omitted. In the pulse timing method, there is no need to provide an offset. However, there is a certain delay from when the microcomputers 38 and 22 start processing for pulse generation until the transmission photocouplers 34S and 24S actually generate pulses. This delay is offset by a pulse interval scheme that controls the time interval between two pulses. Therefore, the opening degree value can be transmitted more accurately by the pulse interval method.

  In the serial data communication system shown in FIG. 17 (g), in the command period Tc, the command signal is transmitted by the transmission signal SD1 expressing the command opening by serial data. That is, serial data representing the command opening is generated. The microcomputer 38 outputs a transmission signal SD1 for turning on / off the light emitting diode LED11 of the transmission photocoupler 34S in a time-series pattern according to the serial data of the command opening, thereby transmitting the command opening. The microcomputer 22 of the electric valve driving device 2 monitors the reception signal RD2 input from the reception photocoupler 24R, and detects the time series pattern (the time series pattern of on / off of the phototransistor PTR22) to detect the serial signal. Data is decoded and command opening is obtained. In this way, the command opening can be transmitted from the control device 3 to the electric valve drive device 2.

  Similarly, when a serial data communication method is used for transmission of a response signal from the motor-operated valve driving device 2 to the control device 3, the transmission signal SD2 corresponding to serial data representing the actual opening of the motor-operated valve 1 is similarly used in the response period Ta. A response signal is transmitted. That is, serial data corresponding to the actual opening is generated. The microcomputer 22 outputs a transmission signal SD2 for turning on / off the light emitting diode LED21 of the transmission photocoupler 24S in a time-series pattern according to serial data representing the actual opening, thereby representing the actual opening. Send a response signal. The microcomputer 38 of the control device 3 monitors the received signal RD1 input from the receiving photocoupler 34R, and detects serial data by detecting the time series pattern (time series pattern of on / off of the phototransistor PTR12). The actual opening is obtained by decoding. Thus, the actual opening degree of the motor-operated valve 1 can be transmitted from the motor-operated valve driving device 2 to the control device 3.

Note that the communication method used for transmission / reception of the command signal and the communication method used for transmission / reception of the response signal may be the same or different. For example, the command signal may be transmitted / received by the pulse width method, while the response signal may be transmitted / received by the pulse interval method. In addition, the above communication methods can be arbitrarily combined.
FIG. 18 is a flowchart for explaining an example of processing executed by the microcomputer 38 of the control device 3. When the electric valve control system 102 is turned on and the microcomputer 38 starts processing, the microcomputer 38 executes initial setting (step S101). The initial setting includes a process for initializing the timers TMR0 and TMR1 to zero, a process for initializing an error flag ERROR indicating occurrence of an abnormality to 0, and a process for initializing the display of the indicators 54, 55, and 56. Including. The timer TMR0 is a timer for measuring the interval T1. The timer TMR1 is a timer for measuring the time within the communication period T2.

  After the initial setting (step S101), the microcomputer 38 controls the power supply switching unit 33 to connect the first DC power supply 31 to the power lines 5A and 5B (step S102). Further, the microcomputer 38 outputs a transmission signal SD1 for holding the light emitting diode LED11 of the transmission photocoupler 34S in a light emitting state. The microcomputer 38 determines whether or not the time measured by the timer TMR0 has reached the interval T1 (step S103). If not, the microcomputer 38 increments the value of the timer TMR0 by +1 (step S104) and determines whether the interval T1 has elapsed. Wait (step S103).

When the time measured by the timer TMR0 reaches the interval T1 (step S103: YES), the microcomputer 38 controls the power source switching unit 33 to switch to the second DC power source 32 (step S105). Are connected to the power lines 5A and 5B.
The microcomputer 38 monitors the input from the reception photocoupler 34R and determines whether the start timing of the communication period T2 has arrived (step S106). When the start timing of the communication period T2 comes (step S106: YES), the microcomputer 38 resets the timer TMR1 to 0 (step S107). When the communication period T2 has already started (step S106: NO), the microcomputer 38 increments the value of the timer TMR1 by +1 (step S108). The subsequent processing branches according to the value of the timer TMR1 (step S109).

  Specifically, when the value of the timer TMR1 is t0 (for example, t0 = 0) or more and less than t1, a command signal output process (step S110) is executed. t1 is set in advance to a value corresponding to the length of the command period Tc. Therefore, the command signal output process is executed in the command period Tc (t0 ≦ TMR1 <t1) within the communication period T2. When the value of timer TMR1 is greater than or equal to t1 and less than t2, a response signal reception process (step S111) is executed. t2 is set to a value corresponding to the length of the communication period T2. Therefore, the response signal reception process is executed in the response period Ta (t1 ≦ TMR1 <t2) within the communication period T2. When the value of the timer TMR1 is other than that, no processing is performed (step S112).

Thereafter, the microcomputer 38 repeats the processing from step S106 while the value of the timer TMR1 is less than t2 (step S113: NO).
On the other hand, when the value of the timer TMR1 becomes t2 or more (step S113: YES), the microcomputer 38 executes an error detection process (step S114) and a state output process (step S115). The error detection process is a process of monitoring the time from the output of the command signal until the response signal indicating the operation of the motor-operated valve 1 corresponding thereto is received, and detecting the presence or absence of an abnormality. The state output process is a process for controlling the opening degree indicator 54, the open / close indicator 55, and the abnormality indicator 56 to output the state of the motor-operated valve 1 and the presence or absence of abnormality.

  Thereafter, the microcomputer 38 resets the timer TMR0 for measuring the interval T1 to 0 (step S116), and returns to step S102. Thereby, the microcomputer 38 controls the power supply switching unit 33 to switch from the second DC power supply 32 to the first DC power supply 31, and controls the light emitting diode LED11 of the transmission photocoupler 34S to be always lit. Accordingly, positive DC power from the first DC power supply 31 is supplied to the power lines 5A and 5B.

  FIG. 19 is a flowchart for explaining a specific example of the command signal output process (step S110). The microcomputer 38 A / D converts the input from the opening command unit 51 to obtain the command opening (step S121). The microcomputer 38 outputs a command signal corresponding to the command opening (step S122). That is, the microcomputer 38 generates a transmission signal SD1 corresponding to the pulse width, frequency, number of pulses, pulse generation timing, pulse interval or serial data (see FIG. 17) corresponding to the command opening, and transmits the photocoupler. The 34S light emitting diode LED11 is driven.

  FIG. 20 is a flowchart for explaining a specific example of the response signal reception process (step S111). The microcomputer 38 monitors the reception signal RD1 input from the reception photocoupler 34R and determines whether or not a response signal has been received (step S131). If no response signal is received (step S131: NO), the process is terminated. When a response signal including information on the actual opening is received (step S131: YES), the microcomputer 38 calculates the actual opening from the response signal (step S132). The calculation of the actual opening is in accordance with a response signal system (see FIG. 17) sent out by the electric valve drive device 2.

  FIG. 21 is a flowchart for explaining a specific example of the error detection process (step S114). When the value of the timer TMR1 reaches t2 and the communication period T2 ends (step S113 in FIG. 18: YES), the microcomputer 38 executes an error detection process (step S114). Therefore, the error detection state is updated every interval T1.

  The microcomputer 38 outputs the command signal in the command signal output process (step S110) until the actual opening calculated from the response signal received in the response signal reception process (step S111) reaches the command opening. The time is monitored (step S141). If this monitoring time exceeds a predetermined time and the time is over (step S142: YES), the microcomputer 38 sets an error flag ERROR indicating the occurrence of an abnormality to 1 (step S143). If the time is not over (step S142: NO), the process ends without setting the error flag ERROR.

  FIG. 22 is a flowchart for explaining a specific example of the state output process (step S115). When the value of the timer TMR1 reaches t2 and the communication period T2 ends (step S113 in FIG. 18: YES), the microcomputer 38 updates the display state of the indicators 54, 55, and 56 (step S114) is executed. That is, the display states of the indicators 54, 55, and 56 are updated every time one communication period T2 ends, and thus updated every interval T1.

The microcomputer 38 outputs the actual opening calculated in the response signal reception process (step S132) to the opening indicator 54 (step S151). Thereby, the opening degree of the motor-operated valve 1 is displayed on the opening degree indicator 54.
Furthermore, if the calculated actual opening degree is 100% (step S152: YES), the microcomputer 38 causes the open / close indicator 55 to perform full open display (step S153), otherwise (step S152: NO), The fully open display is turned off (step S154). If the calculated actual opening is 0% (step S155: YES), the microcomputer 38 causes the open / close indicator 55 to perform a fully closed display (step S156), otherwise (step S154: NO). Then, the fully closed display is turned off (step S157). Furthermore, if the error flag ERROR is 1 (step S158: YES), the microcomputer 38 turns on the abnormality indicator 56 (step S159), otherwise (step S158: NO), and ends the process. As a result, the fully open display and the fully closed display of the open / close indicator 55 are turned on / off according to the actual opening, and when the error flag ERROR becomes 1, the abnormality indicator 56 is held in the error display state. Thereby, whether or not the motor-operated valve 1 is fully opened, whether or not the motor-operated valve 1 is fully closed, and whether or not an abnormality has occurred are displayed, and information corresponding to the user is notified by the display.

  FIG. 23 is a flowchart for explaining a specific example of processing by the microcomputer 22 of the electric valve driving device 2. When electric power is supplied from the power lines 5A and 5B to the motor-operated valve driving device 2, and the microcomputer 22 starts processing, the microcomputer 22 executes initial setting (step S161). The initial setting includes a process for initializing timer TMR2 to 0 and a process for stopping electric motor 20. The timer TMR2 is a timer for measuring the time within the communication period T2. Further, the microcomputer 22 outputs a transmission signal SD2 for holding the light emitting diode LED21 of the transmission photocoupler 24S in a light emitting state.

  After the initial setting, the microcomputer 22 monitors the input from the reception photocoupler 24R to determine whether the start timing of the communication period T2 has arrived (step S162). When the start timing of the communication period T2 comes (step S162: YES), the microcomputer 22 resets the timer TMR2 to 0 (step S163). When the communication period T2 has already started (step S162: NO), the microcomputer 22 increments the value of the timer TMR2 by +1 (step S164). The subsequent processing branches according to the value of the timer TMR2 (step S165).

  Specifically, when the value of the timer TMR2 is t0 (for example, t0 = 0) or more and less than t1, a command signal reception process (step S166) is executed. t1 is set in advance to a value corresponding to the length of the command period Tc. Therefore, the command signal reception process is executed in the command period Tc (t0 ≦ TMR2 <t1) within the communication period T2. When the value of timer TMR2 is not less than t1 and less than t2, a response signal transmission process (step S167) is executed. t2 is set to a value corresponding to the length of the communication period T2. Therefore, the response signal transmission process is executed in the response period Ta (t1 ≦ TMR2 <t2) within the communication period T2. When the value of the timer TMR2 is other than that, no processing is performed (step S168).

Thereafter, the microcomputer 22 repeats the processing from step S162 while the value of the timer TMR2 is less than t2 (step S169: NO).
On the other hand, when the value of the timer TMR2 reaches t2 (step S169: YES), the microcomputer 22 executes a motor control process (step S170) for controlling the driving of the electric motor 20.

Thereafter, the microcomputer 22 returns to step S162 and repeats the process.
FIG. 24 is a flowchart for explaining a specific example of the command signal reception process (step S166). The microcomputer 22 monitors the reception signal RD2 input from the phototransistor PTR22 of the reception photocoupler 24R and determines whether or not a command signal has been received (step S171). If no command signal is received (step S171: NO), the process is terminated. When the command signal is received (step S171: YES), the microcomputer 22 calculates the command opening based on the command signal (step S172).

  The interpretation of the command signal, that is, the calculation of the command opening, follows a predetermined communication method. That is, the command signal communication method is defined, for example, as a pulse width method, a frequency method, a pulse number method, a pulse timing method, a pulse interval method, or a serial data method (see FIG. 17). Accordingly, the microcomputer 22 interprets the command signal and obtains the command opening.

  FIG. 25 is a flowchart for explaining a specific example of the response signal transmission process (step S167). The microcomputer 22 A / D converts the input signal from the opening detection unit 52 to obtain the actual opening of the motor operated valve 1 (step S181). The microcomputer 22 outputs a response signal by performing on / off control of the light emitting diode LED21 of the transmission photocoupler 24S with the transmission signal SD2 representing the actual opening (step S182). The format of the response signal follows a predetermined communication method. That is, the response signal communication method is determined, for example, as a pulse width method, a frequency method, a pulse number method, a pulse timing method, a pulse interval method, or a serial data method (see FIG. 17). According to the determined communication method, the microcomputer 22 sets the pulse width, the number of frequency pulses, the pulse generation timing, the pulse interval, or the serial data according to the actual opening value, and the light emitting diode LED21 of the transmission photocoupler 24S. ON / OFF control.

  FIG. 26 is a flowchart for explaining a specific example of the motor control process (step S170). When the value of the timer TMR2 reaches t2 and the communication period T2 ends (YES in step S169 in FIG. 23), the microcomputer 22 executes a motor control process (step S170) for updating the driving state of the electric motor 20. To do. That is, the driving state of the electric motor 20 is updated every time one communication period T2 ends, and therefore updated every interval T1.

  The microcomputer 22 performs A / D conversion on the input from the opening detection unit 52 to obtain the actual opening of the motor-operated valve 1 (step S191). Further, the microcomputer 22 compares the actual opening and the command opening calculated in the command signal reception process (step S166) (step S192), and updates the driving state of the motor based on the comparison result (step S192). Steps S193, S194, S195).

  More specifically, if the command opening is larger than the actual opening, the microcomputer 22 inputs a drive signal for driving the electric motor 20 in the forward rotation direction (opening direction) to the motor drive circuit 21 ( Step S193). Thereby, electric power is supplied to the electric motor 20, the electric motor 20 rotates in the normal rotation direction (opening direction), and the electric valve 1 is opened. On the other hand, if the command opening is smaller than the actual opening, the microcomputer 22 inputs a drive signal for driving the electric motor 20 in the reverse direction (closed direction) to the motor drive circuit 21 (step S194). Thereby, electric power is supplied to the electric motor 20, the electric motor 20 rotates in the reverse rotation direction (closing direction), and the electric valve 1 is closed. If the command opening and the actual opening are equal, the microcomputer 22 stops driving the electric motor 20 (step S195).

By repeating such an operation, the actual opening of the motor-operated valve 1 is guided to the command opening.
Also in the second embodiment, the same effects as those of the first embodiment described above can be realized, and in particular, the wiring laid between the control device 3 and the electric valve driving device 2 can be greatly reduced.
And according to this 2nd Embodiment, the opening degree instruction | command which commands the opening degree of the motor operated valve 1 can be given with respect to the motor operated valve drive apparatus 2 from the control apparatus 3, Thereby, The opening can be controlled. A response signal indicating the actual opening degree of the motor-operated valve 1 is sent from the motor-operated valve driving device 2 to the control device 3. Thereby, the control device 3 can monitor the actual opening of the motor-operated valve 1.

FIG. 27 is an electric circuit diagram showing the configuration of the motor-operated valve control system 201 according to the first comparative example, and shows a configuration example for controlling the opening and closing of the motor-operated valve 1. For comparison, in FIG. 27, the corresponding parts in FIG.
The control device 3 includes a single DC power supply 211. The DC power generated by this one DC power supply 211 is supplied to the electric motor 20 (DC motor) of the electric valve driving device 2 via the pair of power lines 5A and 5B, and the electric motor 20 is driven. The control device 3 includes an open / close command unit 212, a fully open lamp LA, and a fully closed lamp LB. The opening / closing command unit 212 is an operation unit operated by a user, and includes first and second switches SW1 and SW2 that are switched in conjunction with each other. The first switch SW1 has an open command contact T1a connected to the positive electrode of the DC power supply 211, a close command contact T1b connected to the negative electrode of the DC power supply, and a common contact T1c connected to the first power line 5A. ing. Thereby, the first switch SW1 has an open command state in which the common contact T1c is connected to the open command contact T1a, a close command state in which the common contact T1c is connected to the close command contact T1b, and the common contact T1c as any contact. It is possible to take a non-command state where no connection is made. The second switch SW2 has an open command contact T2a connected to the negative electrode of the DC power supply 211, a close command contact T2b connected to the positive electrode of the DC power supply 211, and a common contact T2c connected to the second power line 5B. doing. Accordingly, the second switch SW2 has an open command state in which the common contact T2c is connected to the open command contact T2a, a close command state in which the common contact T2c is connected to the close command contact T2b, and the common contact T2c as any contact. It is possible to take a non-command state where no connection is made. By the user's operation, the first and second switches SW1 and SW2 are switched in association with each other, and are set to an open command state, a close command state, and a non-command state, respectively.

Fully opened lamp LA and fully closed lamp LB are connected in parallel to the negative electrode of DC power supply 211. The fully open lamp LA and the fully closed lamp LB are connected to a fully open signal line 213 and a fully closed signal line 214 laid between the control device 3 and the electric valve drive device 2, respectively.
The electric valve driving device 2 includes a normally closed full-open limit switch LS1 in which a normally closed contact T3b is connected to the positive terminal of the electric motor 20, and a normally closed type in which a normally closed contact T4b is connected to the negative terminal of the electric motor 20. And a fully-closed limit switch LS2. The common contact T3c of the fully open limit switch LS1 is connected to the first power line 5A. A diode 215 is connected between the power line 5A and the positive terminal of the electric motor 20 in parallel with the fully open limit switch LS1. The normally open contact T3a of the full open limit switch LS1 is connected to the full open signal line 213. On the other hand, the common contact T4c of the fully closed limit switch LS2 is connected to the second power line 5B. In parallel with the fully closed limit switch LS2, a diode 216 is connected between the power line 5B and the negative terminal of the electric motor 20. The normally open contact T4a of the fully closed limit switch LS2 is connected to the fully closed signal line 214.

  When the user operates the opening / closing command unit 212 to input an opening command, the first and second switches SW1, SW2 are each in the opening command state. At this time, the positive electrode of the DC power supply 211 is connected to the first power line 5A, and the negative electrode of the DC power supply 211 is connected to the second power line 5B. Therefore, the current from the DC power supply 211 flows from the first switch SW1 to the first power line 5A, and is further supplied to the electric motor 20 through the full-open limit switch LS1 of the electric valve drive device 2. Thereby, the electric motor 20 rotates in the forward rotation direction, and drives the electric valve 1 in the opening direction. The current exiting the electric motor 20 flows to the second power line 5B through the diode 216, and reaches the negative electrode of the DC power supply 211 through the second switch SW2.

  When the motor-operated valve 1 reaches the fully open position, the fully open limit switch LS1 is switched to the normally open contact T3a side. Thereby, since the electric current path between the 1st electric power line 5 and the electric motor 20 is opened, the electric motor 20 stops. On the other hand, the first power line 5A is connected to the full open signal line 213 via the full open limit switch LS1. Therefore, the current from the first power line 5A is supplied to the fully open signal line 213, and the fully open lamp LA is turned on.

  When the user operates the open / close command unit 212 to input a close command, the first and second switches SW1 and SW2 enter the close command state. At this time, the positive electrode of the DC power supply 211 is connected to the second power line 5B, and the negative electrode of the DC power supply 211 is connected to the first power line 5A. Therefore, the current from the DC power supply 211 flows from the second switch SW2 to the second power line 5B, and is further supplied to the electric motor 20 through the fully closed limit switch LS2 of the electric valve driving device 2. Thereby, the electric motor 20 rotates in the reverse rotation direction, and drives the electric valve 1 in the closing direction. The current exiting the electric motor 20 flows to the first power line 5A through the diode 215, and reaches the negative electrode of the DC power supply 211 through the first switch SW1.

  When the motor-operated valve 1 reaches the fully closed position, the fully closed limit switch LS2 is switched to the normally open contact T4a side. Thereby, since the electric current path between the 2nd electric power line 5B and the electric motor 20 is opened, the electric motor 20 stops. On the other hand, the second power line 5B is connected to the fully closed signal line 214 via the fully closed limit switch LS2. Therefore, the current from the second power line 5B is supplied to the fully closed signal line 214, and the fully closed lamp TB is turned on.

Thus, in this comparative example, in addition to the pair of power lines 5A and 5B, a pair of signal lines 213 and 214 are provided, and these are laid between the control device 3 and the motor-operated valve drive device 2, thereby 1 drive and confirmation of its operating state are achieved.
When this comparative example is compared with the first embodiment described above, in the first embodiment described above, the pair of signal lines 213 and 214 are omitted, and the control device 3 and the motor-operated valve drive device 2 are not connected. The number of wires has been reduced. As a result, the number of wires can be reduced, and a configuration for avoiding interference between the power line and the signal line can be omitted. Therefore, the configuration of the wiring becomes simple, the wiring material cost can be reduced accordingly, and the wiring work can be reduced, so that the cost can be greatly reduced. Also, when the wiring is housed in the pipe, the pipe diameter can be reduced, or a configuration for avoiding signal interference in the pipe can be omitted, so that a significant cost reduction can be achieved.

FIG. 28 is an electric circuit diagram showing the configuration of the motor-operated valve control system 202 according to the second comparative example, and shows a configuration example for controlling the opening degree of the motor-operated valve 1. For comparison, in FIG. 28, the corresponding parts in FIGS. 16 and 27 are denoted by the same reference numerals.
The control device 3 includes a single DC power supply 211. The DC power generated by this one DC power supply 211 is supplied to the electric motor 20 (DC motor) of the electric valve driving device 2 via the pair of power lines 5A and 5B, and the electric motor 20 is driven. The control device 3 includes an opening degree command unit 222, an opening degree indicator 223, and a full open / full close indicator 224. The opening degree command unit 222 is an operation unit operated by a user, and is composed of, for example, a variable resistor, for commanding the opening degree of the motor-operated valve 1 to an arbitrary opening degree between fully open and fully closed. Is a unit.

  The opening command unit 222 is connected to a pair of opening command lines 225 and 226 laid between the control device 3 and the motor-operated valve driving device 2, and between the pair of opening command lines 225 and 226. The command opening is transmitted by a voltage (for example, 1 V to 5 V) or a current (for example, 4 mA to 20 mA) flowing through these opening command lines 225 and 226. The opening indicator 223 is connected to a pair of opening signal lines 227 and 228 laid between the control device 3 and the motor-operated valve driving device 2, and between the pair of opening signal lines 227 and 228. The actual opening (detected opening) of the motor-operated valve 1 is transmitted by a voltage (for example, 1 V to 5 V) or a current (for example, 4 mA to 20 mA) flowing through these opening signal lines 227 and 228. . The full open / full close indicator 224 is connected to a full open signal line 229 and a full close signal line 230 laid between the control device 3 and the electric valve drive device 2.

  The electric valve driving device 2 includes a valve position control unit 240 that controls the position of the electric valve 1, a normally closed full-open limit switch LS1 that is connected to a positive terminal of the electric motor 20 and a normally closed contact T3b, A normally closed full-closed limit switch LS2 having a normally closed contact T4b connected to the negative terminal of the electric motor 20 and an opening detection unit 245 for detecting the opening of the electric valve 1 are included. The valve position control unit 240 includes a bridge circuit 241 of four switching elements Sa1, Sa2, Sb1, and Sb2, and a control circuit 242 that controls the switching elements Sa1, Sa2, Sb1, and Sb2. The common contact T3c of the fully open limit switch LS1 is connected to one output terminal of the bridge circuit 241. In parallel with the fully open limit switch LS1, a diode 215 is connected between the bridge circuit 241 and the positive terminal of the electric motor 20. The normally open contact T3a of the full open limit switch LS1 is connected to the full open signal line 229. On the other hand, the common contact T4c of the fully closed limit switch LS2 is connected to the other output terminal of the bridge circuit 241. A diode 216 is connected between the bridge circuit 241 and the negative terminal of the electric motor 20 in parallel with the fully closed limit switch LS2. The normally open contact T4a of the fully closed limit switch LS2 is connected to the fully closed signal line 230. The opening degree detection unit 245 includes, for example, a potentiometer that is linked to the position of the valve body of the motor-operated valve 1, and an output signal thereof is input to the valve position control unit 240 as an opening degree signal.

  When the user operates the opening command unit 222 and inputs the opening command, the command opening corresponding to the opening command flows through the voltage signal appearing between the pair of opening command lines 225 and 226 or through them. The electric signal is transmitted to the electric valve driving device 2 as a current signal. In the electric valve drive device 2, the control circuit 242 switches the bridge circuit 241 based on the command opening signal from the opening command lines 225 and 226 and the actual opening signal input from the opening detection unit 245. The elements Sa1, Sa2, Sb1, and Sb2 are controlled.

  More specifically, the control circuit 242 compares the command opening and the actual opening. When the command opening is larger than the actual opening, the control circuit 242 causes the pair of switching elements Sa1 and Sa2 to conduct and the other pair. The switching elements Sb1 and Sb2 are turned off. Thereby, the current from the DC power supply 211 is supplied to the electric motor 20 from the first power line 5A through the bridge circuit 241 and further through the full-open limit switch LS1. Thereby, the electric motor 20 rotates in the forward rotation direction, and drives the electric valve 1 in the opening direction. The current exiting the electric motor 20 returns to the bridge circuit 241 via the diode 216 and flows to the second power line 5B, and reaches the negative electrode of the DC power supply 211.

  When the motor-operated valve 1 reaches the fully open position, the fully open limit switch LS1 is switched to the normally open contact T3a side. As a result, the current path between the bridge circuit 241 and the electric motor 20 is opened, and the electric motor 20 stops. On the other hand, the first power line 5A is connected to the fully open signal line 229 via the bridge circuit 241 and the fully open limit switch LS1. As a result, the fully open / fully closed indicator 224 is notified of the fully open state.

  When the command opening is larger than the actual opening, the control circuit 242 causes the pair of switching elements Sb1 and Sb2 to conduct, and sets the other pair of switching elements Sa1 and Sa2 to the cutoff state. As a result, the current from the DC power supply 211 is supplied from the first power line 5A through the bridge circuit 241 to the electric motor 20 through the fully closed limit switch LS2. Thereby, the electric motor 20 rotates in the reverse rotation direction, and drives the electric valve 1 in the closing direction. The current exiting the electric motor 20 returns to the bridge circuit 241 via the diode 215 and flows to the second power line 5B, and reaches the negative electrode of the DC power supply 211.

  When the motor-operated valve 1 reaches the fully closed position, the fully closed limit switch LS2 is switched to the normally open contact T4a side. As a result, the current path between the bridge circuit 241 and the electric motor 20 is opened, and the electric motor 20 stops. On the other hand, the first power line 5A is connected to the fully closed signal line 230 via the bridge circuit 241 and the fully closed limit switch LS2. As a result, the fully open / fully closed indicator 224 is notified of the fully closed state.

In this way, the control circuit 242 controls the bridge circuit 241 based on the comparison between the command opening and the actual opening, so that the electric motor 20 is driven in the forward rotation direction or the reverse rotation direction. The actual opening of 1 is led to the command opening.
In this comparative example, in addition to a pair of power lines, three pairs of signal lines 225, 226; 227, 228; 229, 230 are provided, and these are laid between the control device 3 and the electric valve drive device 2, The opening control of the motor-operated valve 1 and the confirmation of its operating state are achieved.

  Comparing this comparative example with the above-described second embodiment, in the above-mentioned second embodiment, the three pairs of signal lines 225, 226; 227, 228; It can be seen that the number of wires between the valve drive device 2 can be greatly reduced. As a result, the number of wires can be reduced, and a configuration for avoiding interference between the power line and the signal line can be omitted. Therefore, the configuration of the wiring becomes simple, the wiring material cost can be reduced accordingly, and the wiring work can be reduced, so that the cost can be greatly reduced. Also, when the wiring is housed in the pipe, the pipe diameter can be reduced, or a configuration for avoiding signal interference in the pipe can be omitted, so that a significant cost reduction can be achieved.

As mentioned above, although two embodiment of this invention has been described, this invention can be implemented with another form as illustrated below.
For example, in the above-described embodiment, the command period Tc and the response period Ta have the same length, but these lengths may be different. In the above-described embodiment, the command period Tc is provided first and the response period Ta is provided later in the communication period T2. However, the order may be reversed. In the above-described embodiment, the communication period T2 is assigned to the command period Tc or the response period Ta. However, a period that is neither the command period nor the response period may exist in the communication period T2. Furthermore, the command period Tc does not need to be continuous within the communication period T2, and may be dispersed in time within the communication period T2. Similarly, the response period Ta need not be a continuous period within the communication period T2, and may be temporally dispersed within the communication period T2. In the above-described embodiment, the command period Tc and the response period Ta are provided in each communication period T2. For example, the communication period T2 in which only the command period Tc is provided is set, or only the response period Ta is set. The provided communication period T2 may be set. For example, a plurality of communication periods T2 may be alternately assigned to the command period and the response period according to a time series.

In the above-described embodiment, the configuration for controlling the motor-operated valve has been described. However, the present invention can also be used for controlling a drive target other than the motor-operated valve.
In addition, various design changes can be made within the scope of matters described in the claims.

101 Electric valve control system (drive control system, first embodiment)
1 Motorized valve (drive target)
2 Electric valve drive device (drive device)
20 Electric motor (electric actuator)
21 Motor drive circuit 22 Microcomputer (actuator control unit, communication control unit)
23 Power supply unit 27 Diode bridge (rectifier circuit)
C capacitor 24 signal transmission / reception circuit 24S transmission photocoupler (transmission unit)
LED21 Light emitting diode (light emitting element)
PTR21 Phototransistor 24R Reception photocoupler (Reception unit)
LED22 Light emitting diode PTR22 Phototransistor (light receiving element)
25 Schottky diode LS1 Fully open detection switch (Open / close detection unit)
LS2 Fully closed detection switch (Open / close detection unit)
3 Control Device 31 First DC Power Supply 32 Second DC Power Supply 33 Power Supply Switching Unit 34 Signal Transmission / Reception Circuit 34S Transmission Photocoupler (Transmission Unit)
LED11 Light emitting diode (light emitting element)
PTR11 Phototransistor 34R Photocoupler for reception (Reception unit)
LED12 Light emitting diode PTR12 Phototransistor (light receiving element)
35 Schottky diode 36 Open / close command switch 38 Microcomputer (communication control unit)
5A 1st power line 5B 2nd power line 102 Electric valve control system (drive control system, 2nd Embodiment)
51 Opening Command Unit 52 Opening Detection Unit 53 Display Unit

Claims (23)

A drive device that drives a drive target, a control device that controls the drive device, and a power line that supplies DC power from the control device to the drive device,
A first DC power source that supplies DC power of a first polarity to the power line; and a second DC power source that supplies DC power of a second polarity opposite to the first polarity to the power line. A power switching unit that connects one of the first DC power source and the second DC power source to the power line, and a current path that passes through the power line during a period in which the second DC power source is connected to the power line. A signal is received by detecting on / off of a current path passing through the power line during a period in which the second DC power supply is connected to the power line, and a control unit side transmission unit that transmits / receives a signal by turning on / off The control device side receiving unit is operated, and the control device side transmitting unit is operated and a signal received by the control device side receiving unit is acquired during a period in which the second DC power source is connected to the power line. Includes a controller-side communication control unit, a
An electric actuator that drives the drive target; an actuator control unit that controls the electric actuator; a power supply unit that supplies direct-current power of the first polarity to the electric actuator; and the second polarity. A drive unit side transmission unit for transmitting a signal by turning on / off a current path through the power line during a period in which the direct current power is supplied to the power line, and the second polarity DC power is supplied to the power line. A drive-unit-side receiving unit that receives a signal by detecting on / off of a current path passing through the power line during a period, and a period during which the second polarity DC power is supplied to the power line. Driving device side communication control unit that operates the driving device side transmission unit and acquires the signal received by the driving device side receiving unit , Including,
Drive control system. The control device side transmission unit includes a phototransistor interposed in the current path, and a light emitting element optically coupled to the phototransistor,
The control device-side receiving unit includes a light emitting diode interposed in the current path so as to be forward with respect to the DC power of the second polarity, and a light receiving element optically coupled to the light emitting diode. ,
The control device has a forward direction with respect to the DC power of the first polarity in parallel with a series circuit of the phototransistor of the control device side transmission unit and the light emitting diode of the control device side reception unit. Further comprising a controller side diode connected to
The driving device side transmission unit includes a phototransistor interposed in the current path, and a light emitting element optically coupled to the phototransistor,
The driving device-side receiving unit includes a light emitting diode interposed in the current path so as to be forward with respect to the second polarity DC power, and a light receiving element optically coupled to the light emitting diode. ,
The driving device has a forward direction with respect to the DC power of the first polarity in parallel with a series circuit of the phototransistor of the driving device side transmitting unit and the light emitting diode of the driving device side receiving unit. The drive control system according to claim 1, further comprising a drive device side diode connected in such a manner.   The said power supply switching unit connects the said 2nd DC power supply to the said power line only for predetermined time by a fixed interval, and connects the said 1st DC power supply to the said power line at other time. Drive control system. The control device side communication control unit sends a command signal for driving the control device side transmission unit to control the drive target to the power line during a period in which the second DC power supply is connected to the power line. And obtaining a response signal from the driving device from a signal received by the control device-side receiving unit,
The drive device side communication control unit acquires a command signal from the control device from a signal received by the drive device side reception unit during a period in which the second polarity DC power is supplied to the power line, And driving the drive unit side transmission unit to send a response signal representing the state of the drive target to the power line,
The drive control system according to any one of claims 1 to 3, wherein the actuator control unit controls the electric actuator according to a command signal acquired by the drive device communication control unit.   A period during which the second DC power supply is connected to the power line is a communication period, and this communication period is a command period for transmitting a command signal from the control device to the drive device, and a response from the drive device to the control device. The drive control system according to any one of claims 1 to 4, wherein communication between the control device and the drive device is executed divided into response periods in which signals are transmitted. The control device side communication control unit, during the command period, causes a pulsed command signal representing a command content by a pulse width to be sent from the control device side transmission unit to the power line,
6. The drive control system according to claim 5, wherein when the drive device-side receiving unit receives a pulse-like command signal during the command period, the drive device-side communication control unit interprets the command content based on the pulse width. . The control device side communication control unit sends a command signal representing the command content by frequency from the control device side transmission unit to the power line in the command period,
6. The drive control system according to claim 5, wherein when the drive device side receiving unit receives a command signal during the command period, the drive device side communication control unit interprets the command content based on the frequency. The control device side communication control unit, during the command period, causes the control device side transmission unit to send a pulsed command signal representing the command content to the power line by the number of pulses,
6. The drive control system according to claim 5, wherein when the drive device-side receiving unit receives a pulse-like command signal during the command period, the drive device-side communication control unit interprets the command content based on the number of pulses. . The control device side communication control unit, during the command period, causes the control device side transmission unit to send out a pulsed command signal representing the command content according to the generation timing within the command period, to the power line,
The drive device side communication control unit, when the drive device side receiving unit receives a pulsed command signal during the command period, interprets the command content based on the reception timing of the pulse within the command period. 6. The drive control system according to 5. The control device-side communication control unit causes the command signal including a pair of pulses representing the command content by the generation interval to be sent from the control device-side transmission unit to the power line during the command period.
6. The drive according to claim 5, wherein when the drive device side receiving unit receives a pair of pulses during the command period, the drive device side communication control unit interprets the command content based on a reception interval of the pair of pulses. Control system. The control device side communication control unit causes the command signal representing the command content by serial data communication to be sent from the control device side transmission unit to the power line during the command period,
The drive control system according to claim 5, wherein the drive device side communication control unit receives the command signal by serial data communication via the drive device side reception unit during the command period and interprets the content of the command. The drive device side communication control unit, during the response period, causes the drive device side transmission unit to send a pulse-like response signal representing the state of the drive target by a pulse width to the power line,
The control device side communication control unit interprets a response content based on a pulse width when the control device side reception unit receives a pulse-like response signal during the response period. The drive control system according to item. The drive device side communication control unit causes the drive device side transmission unit to send a response signal representing the state of the drive target by frequency to the power line during the response period,
The said control apparatus side communication control unit interprets a response content based on the frequency, if the said control apparatus side receiving unit receives a response signal in the said response period, The Claim 5 any one of Claims 11-11 Drive control system. The drive device side communication control unit, during the response period, causes the drive device side transmission unit to send a pulse-like response signal representing the state of the drive target by the number of pulses to the power line,
The control device-side communication control unit interprets the response content based on the number of pulses when the control device-side receiving unit receives a pulse-like response signal during the response period. The drive control system according to item. The drive device side communication control unit, in the response period, causes the drive device side transmission unit to send a pulse-like response signal representing the state of the drive target according to the generation timing within the response period to the power line,
The control device side communication control unit, when the control device side receiving unit receives a pulse-like response signal during the response period, interprets the response content based on the reception timing of the pulse within the response period. The drive control system as described in any one of 5-11. In the response period, the drive device side communication control unit causes a response signal including a pair of pulses representing the state of the drive target by an occurrence interval to be sent from the drive device side transmission unit to the power line,
The control device side communication control unit interprets the response content based on the reception interval of the pair of pulses when the control device side reception unit receives a pair of pulses during the response period. The drive control system according to claim 1. The drive device side communication control unit sends a response signal representing the state of the drive target by serial data communication from the drive device side transmission unit to the power line during the response period,
The control device side communication control unit receives the response signal by serial data communication via the control device side reception unit during the response period, and interprets the response content. The drive control system described. The driving object includes an electric valve driven by the electric actuator,
The command by the command signal includes an open command to open the motor-operated valve and a close command to close the motor-operated valve,
The drive control system according to any one of claims 5 to 17, wherein the state of the motor-operated valve represented by the response signal includes an open state of the motor-operated valve and a closed state of the motor-operated valve. The drive device further includes an open / close detection unit that detects an open state and a closed state of the electric valve,
The drive control system according to claim 18, wherein the response signal represents a detection state of the open / close detection unit. The driving object includes an electric valve driven by the electric actuator,
The command by the command signal includes an opening command that commands the opening of the motor-operated valve,
The drive control system according to any one of claims 5 to 19, wherein the state of the motor-operated valve represented by the response signal includes an actual opening degree of the motor-operated valve. The drive device further includes an opening degree detection unit that detects an actual opening degree of the electric valve,
The drive control system according to claim 20, wherein the response signal represents an actual opening detected by the opening detection unit.   The drive according to any one of claims 1 to 21, wherein the power supply unit of the drive device includes a rectifier circuit connected to the power line, and supplies the electric actuator rectified by the rectifier circuit to the electric actuator. Control system.   The drive control system according to claim 22, wherein the power supply unit further includes a capacitor connected to an output side of the rectifier circuit.

Images