JP2806077B2 - 2-wire remote controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a controller for controlling a load such as a water heater and an air conditioner, and a remote controller for performing operation and display. The present invention relates to a two-wire remote control device that performs power supply from a main body to a remote control device and signal transmission between the controller main body and the remote control device in a time sharing manner.

[0002]

2. Description of the Related Art Conventionally, as a two-wire type remote control device of this kind, there has been proposed a method of providing a switch circuit for alternately switching a power supply circuit and a signal transmission circuit (see Japanese Patent Publication No. 60-59896). ). FIG. 4 shows a circuit diagram of this conventional example, in which a controller body 30 and a remote controller 3
1 are connected by two electric wires, and a transistor 32,
When the switch 33 is turned on, power is supplied to the remote controller 31. When the transistors 32 and 33 are turned off, the transistor 34 is turned on and off to perform signal transmission. The voltage waveforms of the two wires between the devices 31 are as shown in FIG. In FIG.
t2 is a signal transmission period, and bi-phase signal transmission is performed starting from the power supply OFF (t1). The peak voltage V at the time of signal transmission is determined by the constant voltage diode 35. Further, t2 to t3 are power supply periods.

[0003]

In such a conventional two-wire remote control device, a power supply circuit and a signal transmission circuit are independent, and a constant voltage circuit for generating a voltage necessary for signal transmission is used. In the above conventional example, the constant voltage diode 35) is required, which causes a problem of increased cost. Further, since the power supply circuit and the signal transmission circuit are alternately switched, the power supply is completely interrupted during the signal transmission. I will. As a countermeasure, increasing the capacity of the smoothing capacitor 36 for stabilizing the power supply of the remote control device increases costs, increases the size of the remote control device itself, shortens the signal transmission time, and reduces the charging period. There is a problem in that when the length is increased, the data amount of one signal transmission is reduced.

The present invention solves the above-mentioned problems, and simplifies the configuration by not switching between a power supply circuit and a circuit for transmitting a signal. The purpose is to reduce the capacity of the capacitor for use.

[0005]

In order to achieve the above object, the present invention provides a controller main body for controlling a load, a control state of the load of the controller main body connected to the controller main body by two electric wires. A remote control device for performing an operation input for setting a display and a control state of the two electric wires;
A DC power supply connected to the book, a power supply circuit for periodically connecting the other electrode of the DC power supply to the other of the two electric wires and supplying power to the remote control device, and a parallel connection to the power supply circuit A pair of transmission circuits for transmitting transmission data by short-circuiting or opening the transmission lines via a constant current circuit based on the transmission data during the power supply stop period, and detecting a voltage pattern between the transmission lines. And a pair of receiving circuits for receiving transmission data.

[0006]

According to the present invention, power can be periodically supplied to a remote control device by a power supply circuit by the above-mentioned means for solving the problems.
In addition, since a small amount of power can be supplied even during signal transmission by a resistor connected in parallel to the power supply circuit, the capacity of the smoothing capacitor of the remote controller can be reduced, and the remote controller can be downsized. Further, by reducing the resistance value of the resistor connected in parallel to the power supply circuit, the impedance between the wires can be reduced, and the noise resistance performance can be improved.

[0007]

An embodiment of the present invention will be described below with reference to FIG.

As shown in the figure, a controller main body (hereinafter, referred to as a main body) controls a load 2 and is connected to a remote controller 3 by two electric wires 4 and 5. The DC power supply 6 supplies power to the remote control device 3, and the DC power supply 7
Supplies power to the control circuit 8 of the main body 1. The power supply circuit 9 supplies power to the remote controller 3. When the control circuit 8 outputs a high output to P1, the transistor 1
0 and 11 are turned on, and the DC power supply 6 is supplied to the remote controller 3 through the electric wire 4. Further, the power supplied to the remote control device 3 through the electric wire 4 is a diode 1 for backflow prevention.
Then, the capacitor 13 is charged into the smoothing capacitor 13 via the transistor 2, and converted into a driving power source for the control circuit 17 by a constant voltage circuit including a transistor 14, a constant voltage diode 15 and a capacitor 16. The resistor 18 is connected to the power supply circuit 9 in parallel. The transmission circuit 19 transmits the transmission data to the remote control device 3 based on the output of the control circuit 8 during the power supply stop period,
The transmission circuit 20 transmits transmission data to the main unit 1 based on the output of the control circuit 17. The receiving circuit 21 receives transmission data from the main body 1, and the receiving circuit 22 receives transmission data from the remote control device 3.

Next, signal transmission in the above configuration will be described. When a low output is applied to P1 by the control circuit 8, the transistors 10 and 11 are turned off, and the electric wire 4 is pulled up to the positive pole of the DC power supply 6 by the resistor 18. In this state, when the control circuit 8 outputs high or low according to the signal to be transmitted to P3, the transistor 23 of the transmission circuit 19 turns on and off, and the voltage waveform of the electric wire 4 becomes as shown in FIG. Then, an inverted waveform of the output to P1 is obtained. On the other hand, when the voltage waveform of the electric wire 4 is the waveform shown in FIG. 2 and the voltage of the electric wire 4 is equal to or less than the Zener voltage VZ of the constant voltage diode 24, the receiving circuit 21
5 is turned off, and if the voltage of the electric wire 4 is equal to or higher than the Zener voltage VZ of the constant voltage diode 24, the transistor 25 is turned on, and the waveform input to P4 of the control circuit 17 is shown in FIG.
It becomes as shown in. Therefore, by decoding the input waveform of P4 in the control circuit 17 by a predetermined method, the data can be used as the transmission data of the control circuit 8. One of the predetermined encoding methods is a bi-phase method. In the case of the waveform shown in FIG. 3, the received data is 11001.

In the transmission circuit 19, a resistor 26 is connected to the emitter of the transistor 23, and a diode 26 is connected to the base.
27 is connected as shown, and the voltage across the resistor 26 becomes the constant voltage VL shown in FIG. That is, when the transistor 23 is on, the current flowing through the resistor 26 is constant, and even if the transistor 23 is erroneously turned on while the transistor 11 is on, a dead short between the power supplies does not occur and the transistors 11 and 23 are destroyed. Can be prevented.
It goes without saying that signal transmission from the remote control device 3 to the main body 1 can be performed in the same manner.

In the signal transmission shown in this embodiment, the electric wire 4 is pulled up by the resistor 18 even during the signal transmission, so that the supply of the current determined by the resistance value of the resistor 18 is performed while the signal is high. Since it can be performed, the capacity of the capacitor 13 can be smaller than that of the related art. Further, in this signal transmission, the dynamic range of the signal can be made substantially the same as the voltage of the power supply 6, so that a large noise margin can be obtained, and further, the impedance of the electric wire 4 can be reduced by increasing the current value. Thus, a signal transmission circuit that is resistant to noise can be provided.

In the above embodiment, the transistor 11
Is turned on and off during the period when the signal is off, the signal is transmitted. However, only during the period when the signal is transmitted from the main body 1 to the remote control device 3, the transistor 23 is turned off.
It is also possible to turn on the transistor 11 during the off period, in which case normal power supply can be performed for about half the time during signal transmission, and the capacitor 13 for smoothing requires only a small capacitance. Become.

Further, as shown in FIG. 2, the voltage VZ for judging the high level and the low level of the signal in each of the receiving circuits 22 and 21 of the main body 1 and the remote controller 3 is changed to the minimum voltage VH on the high side during signal transmission. And the voltage VL at the time of low, it is possible to perform more stable high level and low level determination.

In the above description, a pair of the main unit 1 and the remote controller 3 has been described. However, it goes without saying that the same signal transmission can be performed with respect to one main unit even if there are a plurality of remote controllers. .

[0015]

As is apparent from the above embodiments, according to the present invention, a power supply circuit for periodically connecting a DC power supply to an electric wire to supply power to a remote control device, and a power supply circuit in parallel with the power supply circuit. Detecting the connected resistor, a pair of transmission circuits for transmitting transmission data by short-circuiting or opening the transmission lines via a constant current circuit based on the transmission data during the power supply stop period, and detecting a voltage pattern between the transmission lines. Since it has a pair of receiving circuits for receiving transmission data, it does not switch between the power supply circuit and the signal transmission circuit, so a constant voltage circuit for signal transmission is not required, and it is pulled up to the power supply even during signal transmission. The power supply is not completely interrupted, the capacity of the smoothing capacitor on the remote control device side can be reduced, and the remote control device can be reduced in size and cost. In addition, since a relatively large current can flow in a circuit for transmitting a signal, the impedance can be reduced, and a signal transmission resistant to noise can be performed. Furthermore, the short circuit between the electric wires can be limited in current by a constant current circuit, so that even if a signal is erroneously transmitted at the time of power supply, it is possible to prevent a component such as a transistor from being destroyed.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of a two-wire remote controller according to an embodiment of the present invention.

FIG. 2 is a voltage waveform diagram between two wires of the two-wire remote control device.

FIG. 3 is an output waveform diagram of a receiving circuit of the two-wire remote controller.

FIG. 4 is a circuit diagram of a conventional two-wire remote controller.

FIG. 5 is a voltage waveform diagram between two wires of the two-wire remote controller.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Controller main body 2 Load 3 Remote control device 4 Electric wire 5 Electric wire 6 DC power supply 9 Power supply circuit 18 Resistance 19, 20 Transmission circuit 21, 22 Receiving circuit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H04Q 9/00

Claims (2)

(57) [Claims] 1. A controller main body for controlling a load, and a remote controller connected to the controller main body by two wires for displaying a control state of a load of the controller main body and inputting an operation for setting the control state. Device and one electrode connected to one of the two wires
A DC power supply connected to the book, a power supply circuit for periodically connecting the other electrode of the DC power supply to the other of the two electric wires and supplying power to the remote control device, and a parallel connection to the power supply circuit A pair of transmission circuits for transmitting transmission data by short-circuiting or opening the transmission lines via a constant current circuit based on the transmission data during the power supply stop period, and detecting a voltage pattern between the transmission lines. A two-wire remote control device comprising: a pair of receiving circuits for receiving transmission data through the remote controller. 2. A method for detecting a voltage pattern in a signal detection circuit, comprising the steps of: determining a high level and a low level of a signal based on a voltage substantially intermediate between an open voltage and a short circuit voltage between the electric wires; 2. The two-wire remote controller according to claim 1, wherein the level and the low level time are measured.