JPS6013560B2 - signal transmission equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a device for transmitting signals through a small number of signal lines.

Conventionally, multiplex transmission systems such as time division and frequency discrimination are often used in signal transmission devices that send signals from a transmitting side to a receiving side through a small number of signal lines.

However, these devices tend to be complicated and expensive. Therefore, a two-signal transmission method using a single-phase alternating current and an anti-parallel circuit of diodes is used to transmit a small number of signals.
However, as the number of signals increases, the number of signal lines also increases,
This would still be uneconomical. This invention improves the above-mentioned drawbacks, and allows three types of signals to be transmitted simultaneously with one signal line.
Another object of the present invention is to provide a signal transmission device that can be constructed at low cost. An embodiment of the present invention will be described below with reference to FIGS. 1 to 11.

In Figure 1, 1 is a three-phase AC power supply, 2R, 2S, 2T
is a three-phase AC power line commonly used on the transmitting side and receiving side, 3 and 4 are secondary side windings 3R to 3T and windings 4R to 4T
The primary winding is a three-phase transformer with power line 2R,
2S and 2T, and the secondary neutral points 3N and 4N are grounded.

5a to 5c are diodes, and 6a to 6c are signal contacts, one end of which is coupled and connected to a signal line 7.

Output relays 8a to 8c are diodes, 9a to 9c are Zena diodes, 10a to 10c are electromagnetic relays, 1
1a to 11c are smoothing capacitors.

Here, the secondary phase voltages of the transformers 3 and 4 are wired to have a phase difference of rad in each corresponding phase.

In the signal transmission device configured as described above, when only the signal contact 6a is closed, the R phase winding 3R of the transformer 3 is connected to the diode 5a, the contact 6a, the signal line 7, and the diode 8a.
~8c, Zena diode 9a~9c, output relay 10a
~10c, windings 4R to 4T of each phase of transformer 4, neutral point 4
Since an open circuit is formed via N and the neutral point 3N of the transformer 3, the terminals of the Zena diode 9a and the output relay 10a, as well as the Zena diode 9b and the output relay 1ob, and the Zena diode 9c and the output relay 10c, are connected to each other. transformer 3
A half-wave rectified voltage of the vector sum of the R-phase voltage and each phase voltage of the transformer 4 is applied.

Here, each phase voltage on the secondary side of the transformer 3 is er, es, e
t, the secondary phase voltages of the transformer 4 are e'r, e's, e't, the voltages across the Zena diode 9a and the output relay 10a are Er, and similarly the Zena diode 9b and the output relay 10b are
ES, Zena diode 9c and output relay 1
If the voltage across 0c is Et, then er=Emsinwt
(Em is the maximum voltage value, w is the angular velocity of the power supply)
, Er=er-e′r:EmsinM-Emsin(w
t-m) = spot m sinM [like < wt < (ka 11)
n: 0, 1, 2, ...] ES: er-e'S: EmSi
nWt-EmSin (book hen) = EmSin (wt-hen)
[(You+ki) m<Wt〈(Kajuzu) 汀n=.

・1・2・---…]Et:er-e't;Emsin
wt-EmSin (wt-gei) = Emsin (M+gei)
It becomes [(Yo・Kyo) 汀<Wt<(Yojutsuzumeke)].

Figure 2 shows the voltage waveforms of er, es, and et at this time.
The voltage waveforms of r, Es, and Et are shown in FIGS. 3 to 5, respectively. As is clear from these figures, only the maximum value of the voltage Er is the bait m, so if the Zener voltage Vz of the Zener diodes 9a to 9c is VzZEm, the output relay 10b
, 10c, no current flows, and only the output relay 10a is approximately E.
A half-wave DC voltage of m is applied, smoothed by the capacitor 11a, current flows through the coil, and the output relay 10a is activated. That is, when the signal contact 6a on the transmitting side is closed, only the corresponding output relay 10a is activated. Similarly, it goes without saying that when another contact 6b or 6c is closed, the corresponding switch 10b or relay 10c is activated. Next, contacts 6a and 6b are
If both are closed at the same time, the secondary R phase of the transformer 3,
A closed circuit is formed between the S-phase two-phase half-wave rectifier circuit and each phase on the secondary side of the transformer 4, and the Zena diodes 9a to 9 at this time
c and the voltages across relays 10a to 10c Er, Es, Et
The voltage waveforms of are as shown in FIGS. 6 to 8, respectively.

As is clear from this figure, since only Er and ES are half-wave DC voltages with a shark-large value of m higher than the Zener voltage Vz, the relays 10a and 10b have a smoothed voltage of about Em as described above. DC voltage is applied, and the relay 10a
, 10b are activated. That is, this indicates that two types of signals were transmitted at the same time. Similarly, it goes without saying that for other combinations of contacts, only the corresponding relays will operate. In addition, when all the contacts 6a to 6c are closed at the same time, a closed circuit is formed between the secondary side three-phase half-wave circuit of the transformer 3 and each secondary side phase of the transformer 4. Time Zena Diodes 9a-9c and Relay 1
The voltage waveforms of the voltages Er, Bs, and Et across 0a to 10c are as shown in FIGS. 9 to 11, respectively.

As is clear from this figure, Er, Es, and Et are all half-wave DC voltages with the maximum value of bait m higher than the Zener voltage yz, so the relay 10a is
A smoothed DC voltage of about Em is applied to all of the relays 10a to 10c, and the relays 10a to 10c operate. That is, this indicates that three types of signals were transmitted at the same time. In the above embodiment, Zena diodes 9a to 9c are used as elements for comparing the composite voltage and the reference voltage on the receiving side.
Although we have shown an example using this, it can be easily implemented using other comparison elements such as voltage relays.

Alternatively, the operating voltage of the output relays 10a to 10c may be set to Vz without using the Zener diodes 9a to 9c. In the above embodiment, the three-phase transformer 3 with its neutral point grounded,
4 shows a device that performs three types of signal transmission, for example, a diode 5c, a contact 6c, a diode 8c, a zener diode 9c, an output relay 10c, and a smoothing capacitor 1.
Needless to say, if 1c is not used, two types of signal transmission can be performed.

As explained above, in the present invention, the secondary sides of the same three-phase AC power supply are arranged in opposite phases to each other on the transmitting side and the receiving side,
A three-phase transformer with a grounded neutral point is connected, and a closed circuit on the transmitting side is formed by the secondary winding of the transmitting transformer, the transmitting contact connected to this, and a rectifying element, and the receiving side A receiving closed circuit is formed by the secondary winding of the transformer, the output relay and the rectifying element following the secondary winding, and the two closed circuits are connected by a signal line.

As a result, a plurality of types of signals can be transmitted simultaneously and stably with a sufficient margin against fluctuations in the power supply voltage using one signal line, and the system can be constructed economically.

Brief Description of the Drawings Fig. 1 is a circuit diagram showing an embodiment of the signal transmission system according to the present invention, Fig. 2 is a voltage waveform diagram of a three-phase AC power supply, and Figs. 3 to 5 are diagrams showing the transmission of one signal. FIGS. 6 to 8 are voltage waveform diagrams of each phase during transmission of two signals, and FIGS. 9 to 11 are voltage waveform diagrams of each phase during transmission of three signals.

1...Three-phase AC power supply, 2R~2T...
Three-phase AC power line, 3... Transmission side three-phase transformer, 4...
...Receiving side transformer, 5a to 5c...Diode, 6a to 6c...Signal contact, 7...
...Signal line, 8a-8c...Diode, 9a
~9c...Zena diode, 10a~10c...
・Output relay.

Note that the same parts in the figures are indicated by the same reference numerals. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11

Claims (1)

[Claims] 1 Three-phase AC power supply, provided on the transmitting side and the receiving side, at least the secondary sides are connected in a star shape, the primary side of each is connected to the three-phase AC power supply, the secondary sides are arranged in opposite phases to each other, and each has a neutral point. a three-phase transformer that is grounded, a transmitting circuit that shorts the windings of at least two phases on the secondary side of the transmitting three-phase transformer, a transmitting contact inserted in series with the transmitting circuit, and a rectifier. a receiving side circuit that short-circuits a winding of each phase on the secondary side of the receiving side three-phase transformer that is in phase with the secondary side winding of the sending side three-phase transformer;
A signal transmission device comprising an output relay and a rectifying element each inserted in series in the receiving circuit, and a signal line connecting the transmitting circuit and the receiving circuit to each other.