JPH0345616B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a multi-point operation type switch circuit in which a plurality of slave units are connected to a dedicated line from a master unit, and the load is controlled by an operating switch of the master unit or slave units. It is related to.

Figure 1 shows a conventional example, in which multiple slave units are connected via a power line 8 led out from the parent unit A'.
B′ is connected. The master unit A' and slave unit B' are connected, for example, by a power line that sends power from an AC power source 1, and a carrier signal is superimposed on the AC power source 1 to load 2.
I'm trying to control it. The parent device A' is configured as follows. That is, a triax TR for controlling the load 2 on and off is connected in series with the load 2, and this series circuit is connected in parallel to the AC power supply 1. Reference numeral 10 denotes a power supply circuit connected in parallel to the AC power supply 1, which supplies power to each circuit in the parent unit A'. 9 includes TRIATSU TR,
This is a load control circuit for controlling the phase and firing of this triac TR. 11 ₁ is load 2
This is an operation unit consisting of an operation switch for on/off control, and the signal from the operation unit 11 ₁ is sent to the signal generation circuit 14 ₁ , and this signal generation circuit 14 ₁ transmits the signal to the transformer T ₂₁ inserted in the power supply line 8 . A signal is conveyed to the power supply line 8 via the power supply line 8. This signal is sent to the signal detection circuit 1 via the transformer _T11 in the parent unit A'.
3 ₁ , and the display section 12 ₁ is detected by this detection signal.
At the same time, a signal is sent to the load control circuit 9 to ignite the triac TR to control the load 2. On the other hand, on the slave device B' side, a signal from the operating section 11 ₁ is detected by the signal detection circuit 13 ₂ via the transformer T ₁₂ , and the on/off state of the load 2 is displayed on the display section 12 ₂ . Therefore, the load 2 is controlled by operating the operation unit 11 ₁ on the parent unit A' side, and the status of the load 2 is displayed on the display unit 12 ₁ of the parent unit A' and the display unit 12 ₂ of the slave unit B'. I will do it. Also, load 2 is applied from the slave unit B' side.
When controlling the sub-device B', the signal from the signal generating circuit 14 ₂ is superimposed on the power of the power line 8 and transmitted via the transformer T ₂₂ by operating the operating section 11 ₂ of the slave device B'. This carrier signal is detected by the signal detection circuit 13 ₂ via the transformer T ₁₂ of slave device B' and displayed on the display section 12 ₂ , and is also detected by the signal detection circuit 13 ₁ via the transformer T ₁₁ of parent device A'. The load control circuit 9 is controlled by this detection signal, and the load 2 is controlled by firing the triac TR. Further, the display section 12 ₁ is driven and displayed using the signal from the signal detection circuit 13 ₁ . Therefore, the load 2 can be controlled on and off by the operations from the parent device A' and the slave device B', and the status of the load 2 can be displayed on the parent device A' and the slave device B'.

This conventional method has many advantages in large-scale systems with a large number of master units A' and slave units B'; In the case of such a small system, there is a problem in that the cost increases due to an increase in the number of parts, adjustments after manufacturing, etc.

FIG. 2 shows another conventional example. Parent device A
A plurality of slave devices B, for example, several slave devices B, are connected to the two-wire dedicated line 6 from . Parent device A is a triax which is a switching element that controls load 2 on and off.
It is composed of a TR, a power generation circuit 5, a control circuit 3, a display circuit 17, and the like. A series circuit of a load 2 such as a lighting fixture or a ventilation fan and a triac TR is connected to an AC power source 1. A diode bridge _DB1 is connected to both ends of the triac TR, and its output voltage is smoothed by a capacitor _C3 to obtain a DC voltage. This diode bridge DB ₁ and capacitor C ₃ constitute a power generation circuit 15 . The control circuit 3 includes an operation switch SW ₁ to control the load 2 on and off, a flip-flop circuit using a two-winding latching relay Ry, and a flip-flop circuit using a two-winding latching relay Ry, and switching a contact r ₂ by the reversal operation of the latching relay Ry to control the operating state of the load 2. light emitting diode display
It consists of LED ₁ , LED ₂ , and a contact _r1 connected to the gate to control the triac TR by inverting the relay Ry. Triack TR
A control signal generating circuit 18 for generating a gate signal is connected to the gate of the triac TR via the contact _r1 . Moreover, the light emitting diode
A display circuit 17 is formed by LED ₁ and LED ₂ .

The connection point between operation switch SW ₁ and relay Ry,
Dedicated lines 6, 6 are led out from the ground, and slave device B is connected to these dedicated lines 6, 6. The slave unit B is composed of an operating switch SW ₂ and a display circuit 7 that determines the level of the DC voltage from the power generation circuit 15 to display the operating state of the load 2. Further, the DC voltage is used as a power source for slave unit B. operation switch
Because SW ₂ is connected between dedicated lines 6 and 6,
It is connected in parallel with operation switch SW ₁ of parent unit A. The display circuit 7 is composed of two Zener diodes ZD ₁ and ZD ₂ for determining signal levels, transistors Tr ₃ and Tr ₄ for driving light emitting diodes LED ₃ and LED ₄ , and the like.

By the way, the triac TR is in an off state when the contact _r1 is in an open state. Therefore, the voltage between terminals T ₁ and _{T 2} of the triac TR becomes the power supply voltage of the AC power supply 1. The voltage obtained by rectifying and smoothing that voltage
Vc, that is, the output voltage of the power generation circuit 15 is approximately √2
×Power supply voltage. Then, this voltage Vc charges the capacitor _C1 with _the voltage divided by the resistor _R1R3 . Next, when the latching relay Ry is driven by the operation of the operation switch SW ₁ and the contact r ₁ is closed, the triax TR is turned on, and the terminals T ₁ and T ₂ of the triax TR are connected as shown in Fig. 3. The voltage waveform will be as follows. At this time, the voltage Vc is
In the case of AC100V power supply voltage, control signal generation circuit 1
It depends on 8, but it will be about 10V. This voltage Vc charges the capacitor _C2 via _the resistor _R4R5 . At this point, when operating switch SW ₁ is operated again, latching relay Ry is reversed and contact r ₁
becomes open and the triack TR turns off. In other words, the power supply voltage of the control circuit 3 and the DC voltage as the transmission signal to the slave unit B when the triac TR is on and off are different. When applying the circuit power supply voltage Vc100V, the triac TR
When the voltage is on, the voltage is approximately several tens of volts, and the tri-attack
When TR is off, the voltage is approximately 140V. Therefore, by looking at this voltage Vc, the state of the parent device A, that is, the operating state of the load 2 can be determined. Therefore, this voltage Vc is
By transmitting data to slave unit B, the voltage on slave unit B side
By determining Vc, the status of parent device A can be determined. Also, as mentioned above, there is an operation switch on the slave B side.
By operating SW ₂ , load 2 can be operated at any number of locations. Therefore, by applying the voltage Vc to the wiring of the parent device AB, the number of wires between the parent device A and the child device B can be reduced to two, making it possible to transmit signals in both directions. In other words, a status signal (display signal) is transmitted from the master unit A to the slave unit B, and an operation signal is transmitted from the slave unit B to the master unit A, respectively. Therefore, power generation circuit 1
5 is connected to the dedicated line 6 via a current limiting resistor R and a diode D for superimposing voltage Vc. Note that the relationship between the voltage Vc and the Zener voltages Vz ₁ and Vz ₂ of the Zener diodes ZD ₁ and ZD ₂ of the slave unit B is as follows.

VcoFF>Vz ₁ >VcoN>Vz ₂ However, VcoFF is the voltage Vc when the triac TR is off, and VcoN is the voltage Vc when the triac TR is on.

Now, when operating switch SW ₁ is not operated on master device A, contact r ₁ is open and contact r ₂ is connected to a○ terminal, no voltage is applied to the gate of triac TR, so triac TR is turned off. , and load 2 is also in the off state.
Further, since the contact point _r2 is on the a○ terminal side, the light emitting diode _LED1 lights up, indicating that the load 2 is in the off state. On the other hand, a voltage is applied to the dedicated line 6 when the load 2 is in an off state without operating the operation switch _SW1 . In other words, the trial
Since TR is off, the voltage Vc of the power generation circuit 15
becomes VcoFF, and this voltage VcoFF is applied to the dedicated line 6 via the signal superimposing diode D. When the voltage of VcoFF is applied to the dedicated line 6, there is a Zener voltage relationship of Vz ₁ > Vz ₂ , so
The Zener diode ZD ₁ turns on and the light emitting diode LED ₃ lights up, indicating that the load 2 is in the off state.

When operation switch SW ₁ is operated, the reset coil RC of the latching relay Ry is energized and reversed since no voltage is applied to the reset coil RC since the contact r ₂ is on the a○ terminal side. to close contact _r1 and turn on triac TR, turning load 2 on. Note that the latching relay Ry maintains this state until the reset coil RC is energized. Also, contact _r2 will be connected to b○ terminal, so the light emitting diode
LED ₂ lights up to indicate that load 2 is on. At this time, since the triac TR is turned on, the voltage Vc of the power generation circuit 15 becomes VcoN, and this voltage VcoN is applied to the dedicated line 6.
On the other hand, on the slave B side, there is a Zener voltage relationship of Vz ₁ > VcoN > Vz ₂ , so the Zener diode
ZD ₂ turns on and light emitting diode LED ₄ lights up, indicating that load 2 is on on the slave unit B side. Now, when operating switch SW ₁ is operated again, the setting coil SC of latching relay Ry is
Contact _R2 is on the b○ terminal side, so no voltage is applied to the reset coil RC of the latching relay Ry.
is excited and reversed, opening the contact r ₁ and turning off the voltage around zero V of the AC power supply 1, and connecting the contact r ₂ to the a○ terminal side to return to the initial state. Also,
Since the operation switch SW ₂ on the slave unit B side is in a parallel relationship with the operation switch SW ₁ on the master unit A, the operation switch
Since operating SW ₂ is the same as operating switch SW ₁ , latching relay Ry repeats the reversal operation in the same manner as above. By configuring the parent device A and child device B as described above, the parent device A
The wiring between the terminal device B and the slave device B is a two-wire dedicated line 6, which enables bidirectional transmission with a simple configuration. In other words, parent device A
Display signals from the light emitting diodes LED ₃ and LED ₄ indicating the operating status of the load 2 are sent from the sub unit B to the slave unit B, and an operation signal for the operating switch SW ₂ is sent from the slave unit B to the master unit A.

In such a conventional example, the power supply and signal are superimposed by the resistor R and diode D of the parent device A,
This method has the problem that the heat generation of the resistor R becomes large when the operation switches SW ₁ and SW ₂ are operated depending on the number of slave units B that can be connected, and the size of the resistor R also becomes large.

The present invention has been provided in view of the above-mentioned points, and an object of the present invention is to provide a circuit configuration that reduces wasteful current consumption and generates as little heat as possible when transmitting power and signals in a superimposed manner to a slave unit. The present invention provides a multi-position operation type switch circuit.

An embodiment of the present invention will be described in detail below with reference to the drawings.
FIG. 4 shows a specific circuit diagram, in which a switching circuit 4 and a current limiting circuit 5 are added between the diode D and the power generating circuit 15 in order to superimpose the voltage Vc of the power generating circuit 15 on the dedicated line. The other configuration of the parent device A is the same as that shown in FIG. On the other hand, on the slave unit B side, a diode bridge DB ₂ is provided to make the connection between the parent unit A and slave unit B non-polarized, and the other configuration is the same as that shown in Figure 2. be. The current limiting circuit 5 is composed of a current detection resistor R ₇ , a resistor R ₈ R ₉ and a transistor Tr ₂ . This current limiting circuit 5 connects a dedicated line 6, which is a signal line, when the operating switch _SW1 is operated.
6, a large current flows due to the short-circuit between the terminals 6 and 6. Therefore, the structure is of a reduction type exhibiting a double-shaped characteristic as shown in FIG. Of course, if the heat generation of the control transistor _Tr1 , which is the switching element of the switching circuit 4, is not a problem, the operation will not change even if the constraint type shown in FIG. 6 is used. The operation of the current limiting circuit 5 is based on the current detection resistor.
Detects the current with _R7 , and if the current exceeds a certain level, the resistor
The voltage drop across _R7 increases, turning on transistor _Tr2 and pulling the base of transistor _Tr1 , turning off transistor _Tr1 . Therefore, voltage Vc from power supply generating circuit 15 is applied to dedicated line 6 via switching circuit 4, current limiting circuit 5 and diode D. Note that the operation is the same as the conventional one. By the way, this switch (master device A)
When used as a wiring device, it becomes necessary to configure it with a built-in built-in switchbox. In other words, it is necessary to make it small. In this case, it is necessary to reduce the amount of heat generated by the transistor _Tr1 as much as possible. This is because the amount of heat generated by the triac TR is determined by the capacity of the control load 2 _{, and considering it as a product, it is necessary to take into account the state in which the operation switch SW 1 can} be kept pressed. The current during operation in _{step 2} is a waste of current, so it is better to keep it as low as possible. Therefore, as described above, in order to reduce the amount of heat generated by the transistor _Tr1 , the current is limited or cut off at a certain current value.

By the way, in the circuit shown in FIG. 4, each time the operation switches SW ₁ and SW ₂ are operated, the two-winding type latching relay Ry operates in reverse, and the load 2 is turned on and off.
Repeat off. While operating switches SW ₁ and SW ₂ are pressed, dedicated lines 6 and 6 are short-circuited, so the voltage on the input side of slave unit B becomes zero V, and therefore, voltage is no longer supplied to slave unit B. light emitting diode
The display of LED ₃ and LED ₄ disappears, indicating a device failure.
Or it may be mistaken for a failure where no voltage is being applied. In addition, the switch circuit is the main unit A1
A plurality of child devices B are connected to the stand. Therefore, it feels strange when the display disappears during operation of the operation switches SW ₁ and SW ₂ . Furthermore, slave unit B may be installed in a different room from the load 2 that it controls, and in this case, if operation switch SW ₂ is left pressed for some reason (such as something remaining hot on the operation surface). Even if the product is old, it is difficult to distinguish between defective equipment, defective power supply, etc. Therefore, in order to solve this problem, we developed a Zener diode ZD ₆ for voltage backup.
A specific circuit diagram in which this is provided is shown in FIG. The circuit shown in Figure 7 is the operation switch for master unit A and slave unit B.
Zener diode between SW ₁ , SW ₂ and ground
ZD ₆ are inserted and connected to each other, and the other circuit configuration is the same as that in FIG. 4.

First, each Zener diode ZD ₁ , ZD ₂ , ZD ₆
The relationship between the voltages VcoN and VcoFF of the power generation circuit 15 is set as follows. In other words, the signal line voltage (voltage between dedicated lines 6 and 6) when the triac TR is on (when the load 2 is on) is several tens of V (VcoN) because the voltage across the triac TR is rectified and smoothed. ). When the triac TR is off (when the load 2 is off), the signal line voltage (the voltage between dedicated lines 6 and 6) is approximately 140V when the input voltage is 100V, since the commercial AC power supply 1 is rectified and smoothed as is. (VcoFF).

VcoFF>Vz ₁ >VcoN>Vz ₂ Vz ₆ >Vz ₂ VcoN≒V _RY +Vz ₆ However, V _RY is the operating voltage of the latching relay Ry.

Here, when the operation switch SW ₁ is not operated, the contact r ₁ is open and turns off the triact TR, turning off the load 2. The contact r ₂ is connected to the a○ terminal side, and the light emitting diode LED ₁ is turned off. Lights up and load 2
is in the off state. In addition, the voltage of the dedicated line 6 is the voltage when the triac TR is off.
VcoFF, and light emitting diode LED ₃ is lit. When operating switch SW ₁ is operated in this state, Zener voltage Vz ₆ of Zener diode ZD ₆ is applied to dedicated line 6, and relay Ry
operates in reverse to close contact r ₁ and close contact r ₂ to the b○ terminal side, igniting triac TR to turn on load 2, and light-emitting diode LED ₂ lights up. On the other hand, on the slave unit B side, since the Zener voltage Vz ₆ is applied to the dedicated line 6, the input voltage is approximately Vz ₆ , and even with this voltage, the Zener diode ZD ₂ is turned on and the light emitting diode is turned on.
Turn on LED ₄ . Even if you stop pressing the operation switch SW ₁ and return it, the voltage VcoN when the triack TR is on is applied to the dedicated line 6, so
The slave unit B is displayed by lighting the light emitting diode LED ₄ .

If you operate operation switch SW ₁ again, the main unit A
The relay Ry operates in reverse to open the contact _r1 , turning off the triax TR near zero V of the AC power source 1, and turning off the load 2. Further, the contact _r2 is closed between the a○ terminals and the light emitting diode _LED1 lights up, indicating that the load 2 is in an off state. At this time, while operating the operation switch SW ₁ , the Zener voltage Vz ₁ of the Zener diode ZD ₁ is applied to the dedicated line 6.
Zener voltage of lower Zener diode ZD ₆
Since Vz ₆ is applied, light emitting diode LED ₃ does not light up in response to the off state of load 2 of slave unit B, but light emitting diode LED ₄ , which lights up in response to the on state of load 2, does not. It stays lit. In other words,
Only while the operation switch SW ₁ is being pressed to change the load 2 from the on state to the off state, the display on the master unit A and the display on the slave unit B are different. The display on the master device A corresponds to the operation of the load 2, but the display on the slave device B shows the operation state opposite to that of the load 2. However, when the operating switch SW ₁ is released, the high voltage when the triac TR is off is applied to the dedicated line 6, so the light emitting diode LED ₃ corresponding to the operating status of the load 2 lights up on the display of the slave unit B. It turns out. Also, even when operating switch SW ₂ of slave unit B, the voltage of dedicated line 6 is always connected to Zener diode ZD ₆ while operating switch SW ₂ is pressed.
Since the Zener voltage becomes Vz ₆ , the light emitting diodes LED ₃ and LED ₄ for operation indication will not go out.
During operation, there may be a discrepancy between the operation display of master unit A and the display of slave unit B, but the operation switch SW ₁ ,
Since the operation time of SW ₂ is short, it does not cause much inconvenience in practical terms. In this way, the voltage backup Zener diode ZD ₆ can be operated using a switch.
By connecting SW ₁ and SW ₂ in series, parent unit A,
Even if the operation switches SW ₁ and SW ₂ are operated for both the slave unit B, the display of the light emitting diodes LED ₃ and LED ₄ of the slave unit B disappears, and there is no discomfort during use. Further, if one operation switch SW ₂ of the many slave devices B remains pressed, the operation and display of the load 2 will not be reversed even if the other operation switches SW ₁ and SW ₂ are operated. When a device malfunctions, the display will not be reversed or it will not light up. The display will not light up if there is a power failure. Therefore, it is easy to distinguish when an abnormality occurs.

As described above, the present invention includes a control circuit that controls a first switching element connected in series with a load connected to an AC power source by operating a first operation switch to turn on and off the load; A parent device is formed with a power generation circuit that generates the voltage across the first switching element as a DC voltage corresponding to the on/off state of the load by operation of the operating switch, and a plurality of devices are connected to a dedicated line from the parent device. , a display circuit that discriminates the signal consisting of DC voltage from the power generation circuit of the main unit, uses the DC voltage as a power source to display the on/off status of the load, and a display circuit that drives the control circuit of the main unit via a dedicated line to display the load. Since the slave device is equipped with a second operation switch configured in parallel with the first operation switch, the load can be controlled by operations from the parent device and the slave device, and the load can be controlled. The operating state can be displayed on both the master device and the child device, and the operating state of the load can be easily determined. In addition, in a case like the present invention in a small system with a small number of slave units, it is particularly important to send and receive DC voltage signals via a dedicated line, compared to the conventional example in which the control signals between the master unit and slave units are composed of carrier waves. Therefore, the number of products is small, the cost is low, and the product can be made compact. Also, since DC voltage is used to send and receive signals between the parent unit and slave units, no noise is generated.
There is no signal leakage to the commercial power supply, and there is no effect on other equipment due to the signal voltage.Furthermore, the signal from the signal voltage generation circuit, which is the transmission signal, uses DC voltage, and the load can be turned on and off using the DC voltage as a power source. Since the status is displayed, there is no need to separately supply power to the child device. Furthermore, a current limiting circuit that limits the current flowing through the switching circuit consisting of a second switching element that controls the current from the power generation circuit exceeds a predetermined value, and a current limiting circuit for coupling the current limiting circuit to the dedicated line. Since the switching element is installed in the parent device, compared to the conventional example in which the current is limited by a resistor, the amount of heat generated by the second switching element can be reduced as the set current increases, although it depends on the set current. In addition, because it limits the current, it does not consume more current than necessary.Furthermore, since conventional current limiting resistors have a large shape and switching elements are generally small, switching circuits and current When a limiting circuit is constructed, the number of parts increases, but the shape can be reduced in size.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a conventional example, FIG. 2 is a specific circuit diagram of another conventional example, FIG. 3 is an operation waveform diagram of the same triax, and FIG. 4 is a specific circuit diagram of an embodiment of the present invention. FIG. 5 is a characteristic diagram of a reduced type of current limiting circuit same as the above, FIG. 6 is a characteristic diagram of a constraint type same as the above, and FIG. 7 is a specific circuit diagram of another embodiment of the same. 1 is an AC power supply, 2 is a load, 3 is a control circuit, 4 is a switching circuit, 5 is a current limiting circuit, 6 is a dedicated line, 7 is a display circuit, 15 is a power generation circuit, A is a master device, B is a child device , SW ₁ is the first operating switch, SW ₂
indicates the second operation switch.

Claims (1)

[Claims] 1 A control circuit that controls a first switching element connected in series with a load connected to an AC power supply by operating a first operation switch to turn on and off the load; A parent unit is formed with a power generation circuit that generates the voltage across the switching element 1 as a DC voltage corresponding to the on/off state of the load, and a plurality of units are connected to a dedicated line from the parent unit, and the power generation circuit of the parent unit is connected to a dedicated line from the parent unit. A display circuit that discriminates a signal consisting of a DC voltage from the DC voltage and uses the DC voltage as a power source to display the on/off status of the load, and a control circuit of the master unit via a dedicated line to control the load and perform the first operation. When the current flowing through a switching circuit consisting of a second switching element that forms a child unit including a second operating switch configured in parallel with the switch and controls the current from the power generation circuit exceeds a predetermined value. A multi-position operation type switch circuit comprising a current limiting circuit for limiting the above-mentioned current and a switch element for connecting the current limiting circuit to a dedicated line in a parent device.