JP2905329B2 - Transmission signal generation method and signal transmission device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission signal generation method and a signal transmission apparatus, and more particularly to a novel transmission signal transmitted using two transmission lines for wiring saving in a lighting control system, a security management system, and the like. And a signal transmission device that enables a transmission terminal to take power from such a transmission signal.

[0002]

2. Description of the Related Art FIG. 10 is a waveform diagram showing a conventional transmission signal. In FIG. 10, one binary signal of the transmission signal, for example, "1" has a voltage of, for example, DC + 24V, and the other binary signal of "0". Is, for example, DC + 8V or less. Therefore, the binary signals “1” and “0” were identified by the level of the voltage.

[0003]

However, in order for a transmission terminal (not shown) to receive power from the transmission signal at the same time as receiving the transmission signal, the voltage level is low when the binary signal "0" continues. For this reason, there is a problem in that power supply is difficult, and it is necessary to provide a dedicated power supply for the transmission terminal. Therefore, the present invention has been made to solve such a problem, and an object of the present invention is to provide a method of generating a transmission signal without requiring a dedicated power supply in a transmission terminal. Another object of the present invention is to obtain a signal transmission device for transmitting such a transmission signal.

[0004]

According to a first aspect of the present invention, there is provided a transmission signal generating method for setting a transmission signal to a predetermined voltage level from a reference voltage level.
Signal is one of the two binary signals and is different from the predetermined value level.
A signal at a certain voltage level is defined as the other binary signal.
When transmitting a signal sequence composed of binary signals,
For each discrimination of the other binary signal, the other
The voltage level is opposite in polarity to the voltage level of the one binary signal
It is intended to generate a transmission signal into the voltage level.

[0005] The signal transmission device according to claim 2 is one of the two.
Transmission signal generation means for generating a transmission signal having a value signal and the other binary signal; two transmission lines extending from the transmission signal generation means; and A plurality of receiving means for receiving both a signal and power from a transmission signal, wherein the transmission signal generation means outputs a DC voltage forming the one binary signal to one of the transmission lines; And the other DC element forming the other binary signal or another DC element that outputs a different DC voltage to the other of the transmission line, and a control unit that operates by switching these switching elements, A rectifier having an input terminal connected between the two transmission lines;
A voltage conversion circuit and a short-circuiting element thereof connected in parallel between output terminals of the rectifying means, and which of a binary signal is received and connected between the voltage conversion circuit and the other transmission line is determined. And a control unit connected to the determination signal generating means and operating the short-circuit element.

[0006]

According to the first aspect of the present invention, if the binary signal "0" is identified as the binary signal "0" at the start, the binary signal "0" is changed to the binary signal "0" during the remaining bit period. The voltage is made to be a voltage of the opposite polarity to "1", and the voltage is rectified so that the receiving means becomes its own power supply.

According to the second aspect of the present invention, when the transmission signal generating means transmits the binary signals "1" and "0" to the receiving means through one of the other transmission lines, the receiving means rectifies the received signal. To determine which binary signal the received signal is.

[0008]

[Embodiment 1] FIG. 1 is a waveform diagram showing a new transmission signal generated according to the present invention. The binary signal "1" of the transmission signal is the same as that of the conventional example. However, if the binary signal "0" is identified at its start as a binary signal "0", then it is brought to a voltage of the opposite polarity to the binary signal "1", i.e. DC-24V, during the subsequent bit period. . Therefore, even if such a binary signal “0” continues, the transmission terminal can rectify and smooth it to use as its own power supply because the voltage level is high.

Embodiment 2 FIG. 2 is a block diagram of a signal transmission apparatus for transmitting the transmission signal described above with reference to FIG. In the figure, 1 is a transmission power supply as transmission signal generating means, 2 is an AC power supply for the transmission power supply 1, 3a and 3b are two transmission lines 4a, 4b, 4c, 4c extending from the transmission power supply 1. .. Are transmission terminals as receiving means connected in parallel between these transmission lines 3a and 3b.

FIG. 3 is a detailed block diagram of the transmission power supply 1 shown in FIG. 2. The transmission power supply 1 is connected to an AC power supply 2 to supply a stable first DC voltage, eg, + 24V, and a second DC voltage, eg, + 5V. A stabilized DC power supply 1a output from output lines 1a1 and 1a2, respectively, and a current limiting circuit unit 1b connected to the stabilized DC power supply 1a to limit current but output + 24V voltage from output line 1b1.
And a control unit 1c that operates using the above-mentioned + 5V from the stabilized DC power supply 1a as a power supply. The control unit 1c is interconnected with the control unit 1c and connected to the current limiting circuit unit 1b. An output switching unit 1d connected to the lines 3a and 3b.

FIG. 4 is a circuit diagram of the control section 1c and the output switching section 1d shown in FIG. 3, and the control section 1c includes a control circuit 1c connected to the output line 1a2 of the stabilized DC power supply 1a.
1, buffers 1c2 and 1c3 connected to the output side of the control circuit 1c1, a comparator 1c4 connected to the input side of the control circuit 1c1, and a current detector connected between the input side of the comparator 1c4 and the ground. And a resistor R1. The output switching unit 1d includes four switching elements, for example, transistors Tr1 to Tr4. For example, the collectors of the transistors Tr1 and Tr2 are connected to the output line 1b1 of the current limiting circuit unit 1b and the ground, respectively, and the base and the emitter are both buffered. 1c2 is connected to the transmission line 3a. Transistor T
For r3 and Tr4, for example, the collectors are output lines 1 respectively.
b1, is connected to the connection point between the comparator 1c4 and the resistor R1, and the base and the emitter are both connected to the output side of the buffer 1c3 and the transmission line 3b.

FIG. 5 shows a transmission terminal such as 4a shown in FIG.
The transmission terminal device 4a includes transmission lines 3a and 3b.
Rectifier means such as diode D having an input terminal connected between
1 to D4, and a transistor Tr as a short-circuit element having, for example, a collector and an emitter connected between output terminals of the diode bridge DB.
5, a voltage conversion circuit 4a1 having an input connected between the collector and the emitter of the transistor Tr5, a control unit 4a2 connected to the output of the voltage conversion circuit 4a1,
An inverter 4a3 connected between the transmission side of the control unit 4a2 and the base of the transistor Tr5, and a resistor R2 and a diode D5 connected in series between the 5V output side of the voltage conversion circuit 4a1 and the transmission line 3b. Determination signal generation means. The receiving side of the control unit 4a2 is connected to a connection point between the resistor R2 and the diode D5.

Next, the operation will be described. First, the control unit 4a2 in the transmission terminal 4a of FIG.
If the binary signal “1” of 0 is transmitted, the binary signal “1” is inverted to the binary signal “0” by the inverter 4a3, so that the transistor Tr5 is off. In this state, the stabilized DC power supply 1a in the transmission power supply 1 of FIG.
Supplies the second DC voltage to the control circuit 1c1 in the control unit 1c of FIG. 4 through the output line 1a2.
1 operates to turn on the transistors Tr1 and Tr4 via the buffers 1c2 and 1c3, respectively, the output line 1b of the current limiting circuit unit 1b shown in FIG.
1 is applied to the input side of the voltage conversion circuit 4a1 through the transistor Tr1, the transmission line 3a, and the diode D1 of the diode bridge DB in the transmission terminal 4a in FIG. 5 ( However, the voltage drops of Tr1 and D1 are ignored). A current i ₁ flowing from the common potential side of the voltage conversion circuit 4a1 to the ground through the diode D4 in the diode bridge DB, the transmission line 3b, the transistor Tr4 and the resistor R1 in FIG. 4 is a binary signal across the resistor R1. A low voltage is generated which represents the occurrence of a "1". The voltage conversion circuit 4a1 charges a built-in capacitor (not shown) by a voltage of about 24V applied to the input side to serve as a power supply of the control unit 4a2, and converts the voltage of about 24V to a voltage of 5V and outputs it. I do. In this state, the diode D5 is turned on, so that the control unit 4a2 receives a low-voltage signal (the potential at the connection point between the resistor R2 and the diode D5) on the receiving side, thereby increasing the value of +2.
It can be determined that 4 V has been transmitted.

Next, when the control section 4a2 transmits a binary signal "0" from the transmitting side to the base of the transistor Tr5 through the inverter 4a3, the transistor Tr5
Turns on to short-circuit the voltage conversion circuit 4a1. As a result, the + applied to the input side of the voltage conversion circuit 4a1
The current i ₀ (> i ₁ ) due to the voltage of 24 V flows to the ground through the transistor T5, the diode D4 in the diode bridge DB, the transmission line 3b, the transistor Tr4, and the resistor R1, and a binary signal “across the resistor R1”. A high voltage is generated which represents the occurrence of a "0". The comparator 1c4 detects the short circuit of the voltage conversion circuit 4a1 based on the voltage change from the low voltage to the high voltage across the resistor R1, and the control circuit 1c1 switches the outputs of the buffers 1c2 and 1c3. Turn on Tr2 and Tr3. Then, DC + 2 from the output line 1b1
4V is applied to the input side of the voltage conversion circuit 4a1 through the transistor Tr3, the transmission line 3b, and the diode D2 in the diode bridge D3. That is, the transmission terminal 4a
-24V, that is, the binary signal "0" of FIG. In this state, since the diode D5 is reverse-biased, the control unit 4a2 receives a 5V signal on its receiving side, and can thereby determine that -24V has been transmitted.

Embodiment 3 FIG. FIG. 6 is a block diagram showing another transmission power supply 1A. An output switching unit 1dA includes a DC stabilized power supply 1a in addition to an output line 1b1 of a current limiting circuit unit 1b.
Only the point connected to the output line 1a1 is different from the output switching unit 1d. That is, as shown in FIG. 7, the operation is completely the same except that the collector of the transistor Tr3 is connected not to the output line 1b1 but to the output line 1a1.

Embodiment 4 FIG. FIG. 8 is a block diagram showing still another transmission power supply 1B. Here, a stabilized DC power supply 1aA is shown.
Are +24 V and +24 from output lines 1a1 and 1a2, respectively.
In addition to outputting 5V, for example, DC + 36V is output from the output line 1a3, and the transistor Tr3 in the output switching unit 1dB is connected to the output line 1a3 as shown in FIG. Therefore, in this example, the transmission terminal 4a
+ 24V and -36V are supplied to the voltage conversion circuit 4a1.

[0017]

As described above, according to the first aspect of the present invention , a signal at a predetermined voltage level from the reference voltage level is output.
One of the binary signals, and a voltage different from the predetermined value level
The signal at the level is defined as the other binary signal, and the binary signal
When transmitting a signal sequence composed of signals, the other 2
Each time the value signal is determined, the voltage level of the other binary signal after the determination is determined.
Voltage level of the opposite polarity to the voltage level of the one binary signal.
Since the transmission signal is generated by converting the signal into a bell, the transmission terminal receiving such a transmission signal has an effect that it can receive power from the power supply in addition to receiving the signal.

According to a second aspect of the present invention, there is provided a transmission signal generating means for generating a transmission signal having one binary signal and the other binary signal, and two transmission signals extending from the transmission signal generating means. And a plurality of receiving means connected in parallel with each other between the transmission lines to receive both a signal and power from the transmission signal, wherein the transmission signal generating means forms the one binary signal One switching element that outputs a DC voltage to one of the transmission lines and the other switching element that outputs the other DC voltage or another DC voltage that forms the other binary signal to the other of the transmission line; And a control unit for switching and operating these switching elements, and the receiving unit is configured to receive the control signal from the 2
Rectifying means having an input terminal connected between the transmission lines, a voltage conversion circuit and a short-circuit element thereof connected in parallel between output terminals of the rectification means, between the voltage conversion circuit and the other transmission line. Discrimination signal generation means for generating a signal capable of discriminating which of the binary signals the connected and received signal is;
Also, since the control unit is connected to the determination signal generating means and operates the short-circuit element, the transmission terminal needs only two transmission lines, that is, wiring, to transmit a signal and receive power supply from the power source, and has a large width. This has the effect of reducing wiring.

[Brief description of the drawings]

FIG. 1 is a waveform diagram showing a transmission signal generated by the method of the present invention.

FIG. 2 is a block diagram showing a signal transmission device of the present invention.

FIG. 3 is a detailed block diagram of the transmission power supply shown in FIG. 2;

FIG. 4 is a circuit diagram of a control unit and an output switching unit shown in FIG.

FIG. 5 is a circuit diagram of the transmission terminal shown in FIG. 2;

FIG. 6 is a detailed block diagram of another transmission power supply.

FIG. 7 is a circuit diagram of a control unit and an output switching unit shown in FIG.

FIG. 8 is a detailed block diagram of still another transmission power supply.

9 is a circuit diagram of a control unit and an output switching unit shown in FIG.

FIG. 10 is a waveform diagram showing a conventional transmission signal.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Transmission power supply 1c Control part 3a, 3b Transmission line 4a, 4b, 4c Transmission terminal device Tr1, Tr2, Tr3, Tr4, Tr5 Transistor DB Diode bridge 4a1 Voltage conversion circuit 4a2 Control part R2 Resistance D5 Diode

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yukio Kida 1-8 Midoricho, Fukuyama City Mitsubishi Electric Corporation Fukuyama Works (56) References JP-A-3-98292 (JP, A) JP-A-5-191318 (JP, A) JP-A-6-62473 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H04L 12/40

Claims (2)

(57) [Claims] (1) a predetermined voltage level from a reference voltage level;
A certain signal is regarded as one of the binary signals,
A signal at a different voltage level is used as the other binary signal.
When transmitting a signal sequence composed of these binary signals,
For each determination of the other binary signal, the other binary signal after the determination
The voltage level of the binary signal is opposite to the voltage level of the one binary signal.
And generating a transmission signal by converting the transmission signal to a neutral voltage level . 2. Transmission signal generating means for generating a transmission signal having one binary signal and the other binary signal, two transmission lines extending from the transmission signal generating means, and between these transmission lines. And a plurality of receiving means connected in parallel to each other to receive both a signal and power from the transmission signal, wherein the transmission signal generating means transmits a DC voltage forming the one binary signal to the transmission line. The other switching element that outputs one switching element that outputs to one side and the DC voltage or another DC voltage that forms the other binary signal to the other side of the transmission line, and switches these switching elements. A rectifying unit having an input terminal connected between the two transmission lines, and a receiving unit connected in parallel between output terminals of the rectifying unit; Voltage conversion circuit and its short elements,
Discrimination signal generation means for generating a signal which is connected between the voltage conversion circuit and the other transmission line and which can determine which of the received signals is a binary signal, and which is connected to the discrimination signal generation means and A signal transmission device comprising a control unit that operates a short-circuit element.