JPS6333385Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an information transmission device that suppresses the code transmission function when a power supply abnormality occurs in a slave station of an information transmission device that operates on commercial power and in heavy-duty electrical equipment that transfers contact information to the device.

Conventionally, in a slave station of an information transmission device,
When the commercial power supply indicated by is interrupted at time _t1 , the relays for heavy electrical equipment that had been energized until then are all turned off as indicated by B. However, since the logic section power supply including the code conversion section of the information transmission equipment slave station and the transmission line coupling section power supply are DC, this DC power supply has a built-in large capacity capacitor for stabilization. Even if a power outage occurs at time _t1 , the DC power supply voltage will gradually drop and will remain at or above the operating limit voltage Vl for a certain period of time until time _t2 .

Therefore, since the information transmission function is not lost between time t ₁ and t ₂ , uplink code transmission information D that should be stopped at t ₁ is sent until time t ₂ based on the master station information update command E. Information that differs from the actual device status will be sent to the master station.

In addition, since information transmission equipment generally implements power supply units separately for each functional unit of the internal circuit, it is important to note that the power supply for the logic section such as the code conversion section in the upstream transmission section and the transmission line coupling section are normal. Ba,
Naturally, the code transmission function is normal, so the master station does not detect a "line disconnection" or "traffic jam."

Therefore, even if an abnormality occurs in a circuit unrelated to the code transmission function of the information transmission device, such as the power supply for the control output relay in the downlink transmission system, the master station will not be able to know about it and will not be able to perform control operations after all. The first thing you notice is that the equipment doesn't work at that point. Therefore, in order for the master station to know if there is an abnormality in the logic section of the information transmission device or the power supply section other than the transmission line coupling section, it is possible to use one upstream contact transmission item for transmission, but this is not a good idea.

The present invention has been devised in view of the above-mentioned drawbacks, and an object of the present invention is to provide a transmission code suppression device when a power supply abnormality occurs.

Next, one embodiment of the present invention will be explained using FIGS. 2 and 3.

Figure 2 shows that when the logic section in the slave station transmits a frequency signal to the transmission line coupling section, an FS modulator is used.
This is applied to both systems in which a U/B (unipolar/bipolar) converter is used when transmitting baseband codes. In the figure, 1 is an input signal from heavy electrical equipment, etc., 2 is a logic part such as a code converter, 31 is a transmission line coupling part, 4 is a transmission line, and 10 is a switch part, which is a relay contact or a switching element 5 made of a semiconductor. have. This switching element 5 is installed between the transmission line coupling section 31 and the logic section 2, and the other end is connected to the OV line, and the circuit is closed when the power supply of each section is abnormal. Therefore, when an abnormality occurs in the power supply, the input of the transmission line coupling unit 31 is connected to the OV line, so the input of the transmission line coupling unit 31 is forcibly held at the space code, and the logic as shown in FIG. The code transmission function due to the residual voltage of section 2 is suppressed. FIG. 3 shows the transmission path coupling section 32.
This is an embodiment in which an FS modulator is used. In this case, the sketch section 10 includes NAND gates 6 and 7, resistors 8 and 9, and a switch 11 in addition to the switching element 5. In FIG. 3, the logic section 2 and the transmission line coupling section 32
Since the switching device 11 is connected to one side of each of the NAND gates 6 and 7 provided in the middle of the It is turned on and contact a becomes OV potential. Therefore, the output of the NAND gate 7 becomes "1", so the input of the transmission line coupling section 32 is forcibly held at the mark code. Also, switch 1
If contacts c and b of 1 are connected, the output of the NAND gate becomes "0" and the input of the transmission line coupling section 32 is forcibly held at the space code. Either can be set arbitrarily depending on the actual situation of the system. can.

Note that the method of detecting the power supply voltage of each part may be a method using a relay, a method using a voltage sensor, or the like.

As is clear from the above, the switch section was provided to forcibly hold the mark or space using the power supply abnormality signal to prevent attempts to continue the previous code transmission due to residual voltage even though the input information has changed due to a power outage. Therefore, the code transmission function is suppressed and erroneous transmission is prevented.

In addition, even in the event of an abnormality in the circuit power supply unrelated to the code transmission function of the information transmission device, the transmitting signal is held in a mark or space and the code transmission function is suppressed, similar to the former case, so the receiving station detects ``transmission congestion.'' This allows you to know when an abnormality occurs.

As described above, the present invention provides a logic unit having a code converter and a slave station of an information transmission device that transmits a signal from this logic unit to a master station via a transmission line coupling unit. This is an information transmission device in which a switch section that operates when an abnormality occurs is connected between the logic section and the transmission line coupling section.
Since it is an information transmission device composed of a NAND gate, a switch, and a switching element that operates when a power supply abnormality occurs, it has the excellent effect of maintaining high reliability without transmitting any erroneous codes.

[Brief explanation of the drawing]

FIG. 1 is a conventional signal state diagram during a power outage, and FIGS. 2 and 3 are embodiments of the present invention, which show a code transmission suppression device during a power failure. 1 is an input signal, 2 is a logic part, 31 and 32 are transmission line coupling parts, 4 is a transmission line, 5 is a switching element, 6 and 7 are
NAND gate, 8 and 9 are resistors, 10 is a switch section, 11 is a changeover, and Vl is an operating limit voltage.

Claims (1)

[Claims for Utility Model Registration] (1) In a slave station of an information transmission device that includes a logic unit having a code converter and a signal from this logic unit that is transmitted to a master station via a transmission line coupling unit, An information transmission device characterized in that a switch section that operates when a power supply abnormality occurs in a slave station is connected between the logic section and the transmission line coupling section. (2) The information transmission device according to claim 1, wherein the switch section is composed of a NAND gate, a switch, and a switching element.