JPS63172071A - Valve control device - Google Patents

Abstract

PURPOSE:To lighten the burden of an operator and prevent erroneous operation by removing the closing action of a valve and making it effect an opening action when a power source recovery is detected in a valve control device which carries out an automatic valve closing action when a power source cut-off occurred. CONSTITUTION:A power source cut-off detecting device 8 is provided on an accident detecting device 6 for detecting the accident of piping. When either of the detecting devices generates a signal, the signal is transmitted to a valve device 2 via OR circuits 7, 4 and a flip-flop 5, to make the valve close. The detected signal Se of the power source cut-off detecting device 8 is inputted into and held by a flip-flop 10. When a power source recovery is detected by a power source detecting device 11, its signal Sr makes the valve device 2 open via an AND circuit 12, an OR circuit 13, and a flip flop 3. Thereby, the valve is automatically opened when the power source is recovered, lightening the burden of an operator while preventing erroneous operation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention (Industrial Application Field) The present invention relates to a valve control device for controlling valves provided in piping.

(Prior art) For example, piping for transporting fluids such as steam, water, or fuel is equipped with valves at key points, and when an abnormality such as a pipe rupture occurs, valves are installed at appropriate locations. The provided valve is automatically closed.

FIG. 2 shows a conventional example of a valve control device that controls a valve in this manner.

In the same figure, an open signal So output when the operation switch 1 is operated to open is applied to the set input terminal of a holding circuit (flip-flop) 3 for holding the opening operation of the valve device 2. , the output of holding circuit 3 rises and the valve device! 2 operates to open.

In addition, a close signal Ss output when the operation switch 1 is operated to close is applied via an OR circuit 4 to a set input terminal of a holding circuit (flip-flop) 5 for holding the closing operation of the valve device 2. and thereby.

The output of the holding circuit 5 rises and the valve device 2 operates to close.

In addition, the piping (the illustrated path) to which this valve device 2 is attached is equipped with a well-known accident detection device 6 for detecting the occurrence of an accident such as a rupture in the piping. The accident detection signal Sd output when 6 detects a piping accident is applied to the reset input terminal of the holding circuit 3 via the OR circuit 7, and is applied to the set input terminal of the holding circuit 5 via the OR circuit 4. has been added to.

Therefore, when the accident detection device 6 detects a piping accident, the holding circuit 3 is reset and the holding circuit 5 is set at the same time, so the opening operation of the valve device 2 is stopped.
The valve device 2 operates to close. Thereby, the effects of piping accidents can be prevented.

Further, the accident detection device i6 is provided with a power failure detection device 8 for detecting the occurrence of a power failure, and the detection signal Se of this power failure detection device 8 is the accident detection signal S.
Similarly to d, the reset input terminal of the holding circuit 3 and the set input terminal of the holding circuit 5 are connected to each other. .

In this way, when the accident detection bag [6] becomes inoperable for detecting piping accidents, the valve is installed for safety! 2 is being closed.

Further, the reset switch 9 is used to reset the holding circuit 5 and stop the closing operation of the valve device 2.

Therefore, when it is confirmed that the piping accident has been recovered after the accident detection device 6 detects the detection operation and the valve device 2 closes, the reset switch 9 is operated to cancel the closing operation of the valve device 2. Then, the valve device 2 was opened by opening the operation switch 1.

(Problem to be solved by the invention) However, in such a conventional device, the power failure detection device 8
Even when the valve device 2 closes due to the detection operation, the valve device 2 automatically closes in the same manner as when the accident detection device 6 detects it, so the power to the accident detection device 6 is restored. At times, it was necessary to open the valve device 2 by the same operation as described above. Further, during the recovery operation, there was also the inconvenience of forgetting to operate the reset switch 9 or the operation switch 1.

Therefore, it is an object of the present invention to provide a valve control device that automatically opens a valve when the power is restored after the accident detection device has cut off the power.

[Structure of the Invention] (Means for Solving Problems) In the present invention, a power recovery detection means for detecting that the power to the accident detection means has been restored is provided, and the power is restored after a power failure occurs to the accident detection means. When the recovery detecting means performs the detection operation, the closing operation of the valve is canceled and the valve is opened.

(Effect) Therefore, when the power to the accident detection device is restored,
Since the valve opens automatically, the burden on the operator can be reduced and there is no risk of erroneous operation.

(Embodiments) Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a valve control device according to an embodiment of the present invention. In this figure, the same parts as those in FIG. 2 are designated by the same reference numerals, and the explanation thereof will be omitted.

In the figure, a detection signal Ss outputted by the power failure detection device 8 when it detects a power failure of the accident detection device 6 is applied to a set input terminal of a holding circuit (flip-flop) 10 and held therein.

A well-known power supply detection device 11 for detecting that the output of this holding circuit 10 and the power supply of the accident detection device 6 are normal.
The detection signals Sr are applied to two input terminals of the AND circuit 12, respectively.

The output of the AND circuit 12 is applied to the set input terminal of the holding circuit 3 together with the open signal SO of the operation switch 1 via the OR circuit 13, and is applied to the holding circuit 5 together with the output signal of the reset switch 9 via the OR circuit 14. The signal is applied to the reset input terminal of the holding circuit 10 via the delay circuit 15 to which a predetermined delay time is set.

Therefore, when the power failure detection device 8 detects the power failure of the accident detection device 6 and outputs the detection signal Se, the detection signal Se is applied to the set input terminal of the holding circuit 3 via the OR circuit 7. Holding circuit 5 via OR circuit 4
is applied to the set input terminal of , the holding circuit 5 is set at the same time as the holding circuit 3 is reset, and as a result,
The opening operation of the valve device 2 is stopped and the valve device 2 automatically closes. At the same time, the output of the holding circuit 10 rises and the AND circuit 12 becomes operable.

Therefore, when the power to the accident detection device 6 is restored thereafter, the detection signal Sr output from the power supply detection device 11 is applied to the set input terminal of the holding circuit 3 via the AND circuit 12 and the OR circuit 13. Also, OR circuit 1
4 to the reset input of the holding circuit 5.

As a result, the closing operation of the valve system @2 is stopped and the opening operation is automatically performed.

Furthermore, the detection signal Sr outputted via the AND circuit 12
is applied to the reset input terminal of the holding circuit 10 when the delay time of the delay circuit 15 has elapsed, so that the holding circuit 1
0 is reset and the held power-off detection information is erased. Therefore, from this point on, it becomes possible to detect power-off and power-recovery again.

[Effects of the Invention] As described above, according to the present invention, when the power to the accident detection device is restored, the valve automatically opens, which reduces the burden on the operator and prevents erroneous operation. Get the effect of having no fear.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a valve control device according to an embodiment of the present invention, and FIG. 2 is a block diagram showing a conventional example of the valve control device. 1... Operation switch, 2... Valve device, 3.5.10
...Holding circuit, 4,7,13.14...OR circuit. 6... Accident detection device, 8... Power failure detection device, 9.
...Reset switch, 11...Power supply detection device, 12
...AND circuit, 15...delay circuit. (7317) Agent: Patent Attorney Noriyuki Chika (
8105) King Hongbun Figure 1 Date Figure 2

Claims (1)

[Claims] Valve control that includes an accident detection means for detecting the occurrence of an accident in the piping, and closes a valve provided in the piping when the accident detection means performs a detection operation and when the power is cut off to the accident detection means. The apparatus includes a power recovery detection means for detecting that the power to the accident detection means has been restored, and a means for canceling the closing operation of the valve and opening the valve based on the detection output of the power recovery detection means. A valve control device characterized by: