JP4481691B2 - Automatic shut-off valve open / close confirmation method and gas supply device operation control method - Google Patents

Description

  The present invention relates to an open / close confirmation method for an automatic shut-off valve of a gas supply device, and an operation control method for a gas supply device using the confirmation method.

Medical air used in hospitals and the like is used for respiratory management such as artificial respiration treatment, but is required to be clean in terms of quality. As a method for supplying such medical air, there is a method in which compressed air obtained by a compressor is treated with a filter, a dryer or the like to remove dust, odor, oil, moisture, harmful bacteria, and the like.
In recent years, a synthetic air supply facility that supplies oxygen and nitrogen separately produced and mixed at a predetermined ratio has been used.

  As a device for supplying such a mixed gas, a mixed gas supply device capable of automatically continuing the production of the mixed gas even in the event of a power failure and capable of supplying a mixed gas having a predetermined composition in a stable state. It has been proposed (see, for example, Patent Document 1).

  This mixed gas supply device includes a controller that controls opening and closing of the shutoff valve according to the pressure detected by a pressure gauge that detects the pressure in the buffer tank, and opens the shutoff valve of the source gas supply path in the event of a power failure. In addition to providing valve means, a mixed gas discharge path provided with a shut-off valve that opens at the time of a power failure and a pressure regulating valve that maintains the primary side pressure at a predetermined pressure is provided downstream from the gas merging portion. Both shut-off valves of the gas supply path and the mixed gas discharge path are opened, the mixed gas is manufactured by supplying the raw gas from each raw gas supply path, and the excess of the manufactured mixed gas is discharged from this mixed gas discharge path. By doing so, the secondary side pressure of the flow regulating valve is formed to be kept at a predetermined pressure.

The shut-off valve used in Patent Document 1 is not a valve that is manually operated by humans, but is automatically operated by an air operated valve that automatically operates by supplying a working gas (generally air) or an electric signal. Such as a solenoid valve. Hereinafter, these are referred to as “automatic shutoff valves” to distinguish them from manually operated shutoff valves.
JP-A-11-76779

  Conventionally, an automatic shut-off valve has been operated by supplying a working gas or sending an electric signal. However, there are cases where the automatic shut-off valve does not respond due to an abnormality or failure even though a signal (command) for opening / closing the automatic shut-off valve is output. In this case, a method for detecting and confirming an abnormality in the opening / closing operation of the automatic shut-off valve has not been proposed yet.

  In view of the above-described problems of the prior art, the present invention provides an automatic shut-off valve opening / closing confirmation method that instantaneously detects an abnormal operation of an automatic shut-off valve that does not open / close in response to an operation signal of the automatic shut-off valve. Objective.

  Another object of the present invention is to provide a method for controlling the operation of a gas supply device using this automatic shut-off valve open / close confirmation method.

To solve this problem,
The invention according to claim 1 is connected to a gas supply line, and is an automatic shut-off valve that shuts off a gas flowing through the gas supply line, and is disposed in front of the automatic shut-off valve to detect the pressure on the primary side line. A first pressure sensor that is disposed downstream of the automatic shut-off valve and adjusts a gas flow rate, and a second pressure sensor that is disposed downstream of the flow rate adjustment valve and detects the pressure of the secondary line. The first pressure sensor is set with an upper limit alarm value of the pressure on the primary side line, and the second pressure sensor is configured to check the opening and closing of the automatic shutoff valve of the gas supply device. In the pressure sensor, an upper limit alarm value of the pressure of the secondary side line is set, an abnormality in the opening operation of the automatic shut-off valve is detected by the upper limit alarm value of the first pressure sensor, and the automatic Abnormalities in the closing operation of the shut-off valve A closing check method for an automatic shut-off valves and detecting the high alarm value of the pressure sensor.

According to a second aspect of the present invention, there is provided a first automatic shut-off valve that shuts off a gas flowing through the gas supply line, and a first automatic shut-off valve that is disposed upstream of the first automatic shut-off valve and detects the pressure of the primary side line A pressure sensor, a flow rate adjusting valve that is disposed downstream of the first automatic shut-off valve and adjusts a gas flow rate, and a second that is disposed downstream of the flow rate adjusting valve and shuts off a gas flowing through the gas supply line. Gas provided with a normal operation gas supply line and a preparatory operation gas supply line having an automatic shut-off valve and a second pressure sensor disposed downstream of the flow rate adjustment valve and detecting the pressure of the secondary side line An operation control method for a supply device, wherein an abnormality in the opening or closing operation of the first automatic shut-off valve in the normal operation gas supply line is detected by the automatic shut-off valve opening / closing confirmation method according to claim 1. If the normal operation Said second automatic shut-off valve of the gas supply line is closed, the a operation control method of the normal gas supply device, characterized in that switching from the operating gas feed line to the preliminary operation for the gas supply line.

  According to the automatic shut-off valve opening / closing confirmation method of the present invention, by providing a plurality of pressure sensors in the gas supply line, an abnormal operation in which the automatic shut-off valve does not open / close with respect to the operation signal of the automatic shut-off valve is detected in advance. It can be detected instantaneously by the preset upper limit alarm value of the pressure sensor.

  Further, according to the operation control method of the gas supply device of the present invention, when the opening / closing operation of the automatic shut-off valve is detected by using the automatic shut-off valve open / close confirmation method, the gas supply device is supplied with gas for normal operation. The operation can be continued by switching from the line to the gas supply line for preliminary operation.

  Hereinafter, an example of a system diagram of a gas supply device according to an embodiment of the present invention will be described in detail with reference to the drawings.

[First Embodiment]
FIG. 1 is a system diagram of a gas supply device according to the first embodiment. The gas supply device 40 of the present embodiment is connected to the gas supply line 1 through which the gas that is the raw material kept at the primary supply pressure flows, and the gas supply line 1, and the gas is supplied to the desired secondary supply pressure. The pressure regulating valve RV-1, the first pressure sensor PT-1, the automatic shutoff valve V-1, the needle valve NV-1 that is a flow regulating valve, and the second pressure sensor PT-2. And a buffer tank 5.

  In the present embodiment, the first pressure sensor PT-1 is provided in front of the automatic shutoff valve V-1, and detects the pressure in the primary line (the pressure of the automatic shutoff valve V-1). belongs to. A pressure sensor such as a piezoresistive semiconductor pressure sensor can be used as the first pressure sensor. An upper limit alarm value is set in advance for the pressure sensor PT-1.

  The automatic shut-off valve V-1 is for shutting off the gas flowing through the gas supply line 1, and is any automatic shut-off valve as long as it automatically opens and closes the valve in response to a valve operation signal. May be. Among these, an air operated valve and a solenoid valve are preferable. The air operated valve consists of a gas operated valve that opens when the working gas is supplied (normally closed type) and a gas operated valve that opens when the working gas is not supplied (normally open type). Any of them may be used.

  The flow rate adjusting valve NV-1 is provided at the subsequent stage of the automatic shutoff valve V-1, and is for adjusting the flow rate of the gas flowing into the buffer tank 5. The flow rate regulating valve NV-1 restricts the gas flow rate to a constant amount, and the gas pressure also decreases to become the secondary line pressure. A needle valve, an orifice, or the like can be used as the flow rate adjusting valve NV-1.

  The second pressure sensor PT-2 is provided in the subsequent stage of the flow rate adjusting valve NV-1, and detects the pressure in the secondary line (the pressure in the buffer tank 5). The second pressure sensor PT-2 can be the same type of sensor as the first pressure sensor PT-1. In the second pressure sensor PT-2, an upper limit alarm value, an upper limit set value, and a lower limit set value are set in advance. Further, an automatic shutoff valve V-1 is set according to the upper limit set value and the lower limit set value. A control mechanism for opening and closing is incorporated.

  The opening / closing operation of the automatic shut-off valve V-1 and the detection of the line pressure by these pressure sensors may be performed by collectively inputting an electric signal to the control panel and performing control / detection.

  In this gas supply device 40, the gas that has flowed from the gas supply line 1 through the pressure adjustment valve RV- 1, the automatic shut-off valve V- 1, and the flow rate adjustment valve NV- 1 is once accumulated in the buffer tank 5 before being used. Supplied to the point.

  FIG. 2 shows a flowchart of the automatic shut-off valve open / close confirmation method according to the present embodiment. For example, 0.72 MPa is set in advance as the upper limit alarm value for the first pressure sensor PT-1, and 0.60 MPa is set as the upper limit alarm value for the second pressure sensor PT-2. Further, the upper limit set value for performing the opening / closing operation of the automatic shutoff valve V-1 is set to 0.54 MPa, and the lower limit set value is set to 0.50 MPa in the second pressure sensor PT-2. With reference to the system diagram of FIG. 1 and the flowchart of FIG. 2, a method for confirming the opening and closing of the automatic shut-off valve according to the present embodiment will be described.

<Pressure at each part>
In the gas supply line 1, the primary supply pressure of the pressure regulating valve RV-1 is set to 0.95 MPa, and the secondary supply pressure is set to 0.70 MPa. When the automatic shut-off valve V-1 is opened, the secondary line pressure of the automatic shut-off valve V-1 is reduced to 0.65 MPa due to pressure loss due to a part in the middle. On the other hand, when the automatic shut-off valve V-1 is closed, the primary side line pressure of the automatic shut-off valve V-1 becomes a static pressure, and the indicated value becomes about 0.80 MPa.

<Checking method when V-1 does not close despite automatic shutoff valve V-1 closing command>
When the use of gas at the use point is stopped in the state where the automatic shutoff valve V-1 is opened (S100), the pressure in the buffer tank 5 increases. When the pressure in the buffer tank 5 is 0.54 MPa or more, the detection mechanism operates because the preset upper limit value 0.54 MPa of the second pressure sensor PT-2 is exceeded (S101). Then, a signal (command) is output to close the automatic shutoff valve V-1 (S102).

  However, if any abnormality or failure occurs in the automatic shut-off valve V-1 and the automatic shut-off valve V-1 does not actually close (S103), the gas continues to flow. The side line pressure does not decrease (S104), but rather increases. Eventually, if the pressure in the buffer tank 5 continues to rise until it reaches 0.60 MPa or higher, the upper limit alarm value 0.62 MPa of the second pressure sensor PT-2 set in advance will be exceeded. Therefore, the detection mechanism operates (S105), and an alarm is issued, so that it is possible to confirm an abnormality in the closing operation of the automatic shutoff valve V-1.

<Confirmation method when V-1 does not open despite automatic shutoff valve V-1 opening command>
On the other hand, if the gas is continuously used at the use point with the automatic shutoff valve V-1 closed (S200), the pressure in the buffer tank 5 decreases. When the pressure in the buffer tank 5 decreases to 0.50 MPa or less, the lower limit set value 0.50 MPa of the second pressure sensor PT-2 that has been set in advance is lowered, so that the detection mechanism operates (S201). ), A signal (command) is output to open the automatic shutoff valve V-1 (S202).

  However, if any abnormality / failure occurs in the automatic cutoff valve V-1 and the automatic cutoff valve V-1 does not actually open (S203), the primary line pressure of the automatic cutoff valve V-1 is the static pressure. The pressure remains 0.80 MPa and does not decrease to the secondary supply pressure 0.70 MPa that has been adjusted and set by the pressure regulating valve RV-1 (S204). Therefore, the primary side line pressure of the automatic shutoff valve V-1 exceeds the preset upper limit alarm value 0.72 MPa of the first pressure sensor PT-1, so that the detection mechanism operates ( S205) When the alarm is issued, it is possible to confirm an abnormality in the opening operation of the automatic shutoff valve V-1.

  In the present embodiment, the first pressure sensor PT-1 is provided upstream of the automatic cutoff valve V-1, but this first pressure sensor PT-1 is subsequent to the automatic cutoff valve V-1. Alternatively, it may be provided upstream of the flow regulating valve NV-1. In that case, the upper limit alarm value of each pressure sensor PT-1, PT-2 is changed and set.

[Second Embodiment]
FIG. 3 is a system diagram of a gas supply device according to the second embodiment. The gas supply apparatus according to the present embodiment includes pressure control valves RV-1 and RV-3 provided in the normal operation gas supply line 10 and the preliminary operation gas supply line 30, respectively, and a first pressure sensor PT-. 1, PT-3, first automatic shut-off valves V-10, V-30, needle valves NV-1, NV-3 which are flow rate adjusting valves, and second automatic shut-off valves V-20, V- 40, the second pressure sensor PT-2 provided in the subsequent stage, and the buffer tank 5.
In the present embodiment, the gas supply line is divided into two types, a second automatic shut-off valve is provided, and the gas supply line is switched between the normal operation and the preliminary operation except for the first embodiment. Since they are the same as those described above, description thereof will be omitted.

  The normal operation gas supply line 10 is a gas supply path used for supplying gas at all times. On the other hand, the gas supply line 30 for preliminary operation is a gas supply path provided so that when an abnormality occurs in the gas supply line 10 for normal operation, it can be switched to here and continuously supplied without stopping the gas. The parts and functions are formed in exactly the same way as the normal operation gas supply line 10.

  Further, the second automatic shutoff valve V-20 in the normal operation gas supply line 10 closes the normal operation gas supply line 10 when the first automatic shutoff valve V-10 breaks down, and is used for preliminary operation. This is for switching to the gas supply line 30. The first automatic shut-off valves V-10 and V-30 and the second automatic shut-off valves V-20 and V-40 of the present embodiment are the same as the automatic shut-off valve V-1 in the first embodiment. A shut-off valve can be used.

  FIG. 4 shows a flowchart of the operation control method of the gas supply apparatus according to the present embodiment. In this embodiment, an upper limit alarm value of 0.72 MPa and a lower limit alarm value of 0.56 MPa are set in advance in the first pressure sensors PT-1 and PT-3. Further, the second pressure sensor PT-2 includes an upper limit alarm value 0.60 MPa, an upper limit set value 0.54 MPa for performing open / close control of the first automatic shut-off valves V-10 and V-30, and a lower limit set value. 0.50 MPa is set. With reference to the system diagram of FIG. 3 and the flowchart of FIG. 4, the operation control method of the gas supply device according to the present embodiment will be described in the normal operation gas supply line 10. The same applies to the preliminary operation gas supply line 30.

<Operation control method when V-10 does not close despite first automatic shutoff valve V-10 closing command>
When the first automatic shutoff valve V-10 provided in the normal operation gas supply line 10 is opened (S100) and the use of gas at the use point is stopped, the pressure in the buffer tank 5 increases. When the pressure in the buffer tank 5 is 0.54 MPa or more, the upper limit set value 0.54 MPa of the second pressure sensor PT-2 that has been set is exceeded, so the detection mechanism operates (S101), A signal (command) is output to close the first automatic shut-off valve V-10 (S102).

  However, if an abnormality or failure occurs in the first automatic shutoff valve V-10 and the first automatic shutoff valve V-10 does not actually close (S103), the gas continues to flow. The secondary line pressure of the shutoff valve V-10 does not decrease (S104). If the pressure in the buffer tank 5 continues to rise until it finally reaches 0.60 MPa or higher, the upper limit alarm value 0.62 MPa of the second pressure sensor PT-2 set in advance will be exceeded. The detection mechanism operates (S105), and an alarm is issued, thereby confirming an abnormality in the closing operation of the first automatic shutoff valve V-10.

  In this embodiment, when the upper limit alarm value of the second pressure sensor PT-2 is detected (S105), a closing signal (command) for the second automatic shutoff valve V-20 provided in the normal operation gas supply line 10 is detected. ) (S303) is output, and the gas supply line is switched from the normal operation 10 to the preliminary operation 30 (S304).

<Operation control method when V-10 does not open despite first automatic shut-off valve V-10 opening command>
When the first automatic shutoff valve V-10 provided in the normal operation gas supply line 10 is closed (S200) and the gas is continuously used at the use point, the pressure in the buffer tank 5 decreases. When the pressure in the buffer tank 5 decreases to 0.50 MPa or less, the lower limit set value 0.50 MPa of the second pressure sensor PT-2 that has been set is below, so the detection mechanism operates (S201). Then, a signal (command) is output to open the first automatic shutoff valve V-10 (S202).

  However, if an abnormality or failure occurs in the first automatic shut-off valve V-10 and the first automatic shut-off valve V-10 does not actually open (S203), the first automatic shut-off valve V-10 The primary line pressure remains at a static pressure of 0.80 MPa (S204). Since the primary line pressure of the first automatic shutoff valve V-10 exceeds the preset upper limit alarm value 0.72 MPa of the first pressure sensor PT-1, the detection mechanism operates. (S205) When the alarm is issued, the abnormality of the opening operation of the first automatic shutoff valve V-10 is confirmed.

  In the present embodiment, when the upper limit alarm value of the first pressure sensor PT-1 is detected (S205), the closing signal (command) of the second automatic shutoff valve V-20 provided in the normal operation gas supply line 10 is detected. ) (S303) is output, and the gas supply line is switched from the normal operation 10 to the preliminary operation 30 (S304).

<Operation control method in case of primary supply pressure drop due to abnormality of pressure regulating valve RV-1>
With the first automatic shut-off valve V-10 provided in the normal operation gas supply line 10 opened (S100), the pressure adjustment valve due to the blockage of the pressure adjustment valve RV-1 or an abnormality in the normal operation gas supply line 10 When a decrease in the primary supply pressure of RV-1 occurs (S301), the pressure from the normal operation gas supply line 10 decreases, so the primary line of the first automatic shutoff valve V-10. Pressure also drops. When this pressure falls below the preset lower limit alarm value 0.56 MPa of the first pressure sensor PT-1, the detection mechanism operates (S302) and an alarm is issued.

Also in this case, a closing signal (command) (S303) of the second automatic shutoff valve V-20 provided in the normal operation gas supply line 10 is output, and the gas supply line is changed from the normal operation 10 to the preliminary operation 30. Switch (S304).
These alarm values are shown in Table 1.

It is a systematic diagram of the gas supply apparatus which concerns on 1st Embodiment. It is a flowchart which shows the opening / closing confirmation method of the automatic cutoff valve which concerns on 1st Embodiment. It is a systematic diagram of the gas supply apparatus which concerns on 2nd Embodiment. It is a flowchart which shows the operation control method of the gas supply apparatus which concerns on 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Gas supply line 10 Gas supply line for normal operation 30 Gas supply line for preliminary operation 40 Gas supply apparatus PT-1, PT-3 First pressure sensor PT-2 Second pressure sensor V-1 Automatic shut-off valve V -10, V-30 First automatic shut-off valve V-20, V-40 Second automatic shut-off valve NV-1, NV-3 Flow rate regulating valve

Claims (2)

An automatic shut-off valve that is connected to the gas supply line and shuts off the gas flowing through the gas supply line;
A first pressure sensor disposed in front of the automatic shut-off valve for detecting the pressure of the primary side line;
A flow rate adjusting valve arranged after the automatic shut-off valve to adjust the flow rate of gas;
A second pressure sensor that is disposed downstream of the flow rate adjusting valve and detects the pressure of the secondary line, and a method for confirming the opening and closing of the automatic shut-off valve of the gas supply device,
In the first pressure sensor, an upper limit alarm value of the pressure in the primary side line is set,
In the second pressure sensor, an upper limit alarm value of the pressure of the secondary side line is set,
An abnormality in the opening operation of the automatic shut-off valve is detected by an upper limit alarm value of the first pressure sensor,
An automatic shut-off valve open / close confirmation method , wherein an abnormality in the closing operation of the automatic shut-off valve is detected by an upper limit alarm value of the second pressure sensor . A first automatic shut-off valve for shutting off a gas flowing in the gas supply line;
A first pressure sensor disposed upstream of the first automatic shut-off valve for detecting the pressure of the primary side line;
A flow rate adjusting valve that is arranged downstream of the first automatic shutoff valve and adjusts the flow rate of gas;
A second automatic shut-off valve that is arranged downstream of the flow rate regulating valve and shuts off a gas flowing to the gas supply line;
Operation control of a gas supply device including a normal operation gas supply line and a preliminary operation gas supply line, and a second pressure sensor that is disposed downstream of the flow rate adjustment valve and detects the pressure of the secondary side line A method,
When detecting the opening / closing operation of the first automatic shutoff valve of the normal operation gas supply line by the method for confirming opening / closing of the automatic shutoff valve according to claim 1,
Closing the second automatic shut-off valve of the normal operation gas supply line;
An operation control method for a gas supply device, wherein the gas supply line for normal operation is switched to the gas supply line for preliminary operation .

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