JPS6117783A - Gas cut-off valve and leakage detector - Google Patents

Abstract

PURPOSE:To prevent a coil from generating heat by providing a cut-off solenoid valve with a suction increasing device. CONSTITUTION:When a gas appliance is not used, as voltage is applied to a base Tr9, the bases Tr8, Tr9 are in the state of a short circuit, so that an electric current is not applied to a cut-off valve. When an appliance cock is opened, the operation of the base Tr9 is stopped and the base voltage of the base Tr8 is increased, so that an electric current is applied to a coil 7 of the cut-off valve. A plunger 9 and a disc 18 are attracted to a plunger bearing 2, so that the cut- off valve is opened. When an electric current flows out from a condenser C5, voltage is caused to drop suddenly by a resistance R24 and a resistance of the coil 7. The plunger 9 and the disc 18 are retained in an adsorbing condition by the plunger bearing 2.

Description

[Detailed Description of the Invention] A common two-piece electromagnetic valve (shutoff valve) is always used in a suction state during use, and since it can be used continuously for more than 10 hours, heat generation in the coil must be avoided. This device takes advantage of the characteristics of the magnet and requires an extremely large amount of current to attract the current, but in the holding state it can be held with just a few tenths of the current required for attraction. Therefore, in this device, the base of (Tr 8) is normally operated, and when the gas appliance is not in use (the appliance plug is not open), voltage is applied to the base of (Tr 9'). (Tr 9) is activated and the base of Tr 8) and the emitter of (Tr 9) are short-circuited and (T
r8) is not activated and the shutoff valve is not energized. When the appliance stopper opens (Tr9) I71! The operation stops and the base voltage of Tr 8) rises, causing the shutoff valve coil ('fr8) to operate.
7) is energized, the coil (7) is energized, 9) the plunger and the 6 o'clock disk are attracted to the plunger receiver (2) against the facing spring, and the shutoff valve is opened. The current stored in the capacitor (C5) shown in this suction port 2 flows out at once. The voltage at that time is 28X1.4X
1. In the state of about 3 to 4V, which drops to 43V during 1.1, (9) the plunger and (B) the disk maintain an adsorbed state on the (2) plunger receiver. Therefore, in 3 to 4, it is possible to save power in terms of power consumption (7) and avoid heat generation in the coil.

(2) Detailed explanation of the pressure switch The pressure sensor of this device detects the pressure change in the wheel pressure sensor (replaces the distortion due to pressure with a change in voltage). Conventionally, a diaphragm was used and a large space was required, but this device requires a small space and can be easily installed in the gas flow path. (4) Attach the strain gauge ■pressure sensor to the sensor set plate (a) Insulate the sensor section plate and (2) the pressure sensor. D) From the sensor set plate 1) Remove the electric wire from the pressure sensor (c) (b) Protect it with a wire holder.) Mount the pressure sensor on the sensor set plate.) Set the pressure sensor on the flange.) Seal it with a sheet seal and (b) mount it with a round machine screw. Installation is done using a flange (
A) is installed in the room between C) and the sensor set plate in order to accurately detect the distortion. When the pressure inside the tube changes (2) the distortion of the sensor also changes and the electrical resistance inside the tube decreases (see Figure 1), which means that the pressure inside the tube decreases, which means that the gas disappears when gas is used, and when it is not used. This indicates a defect in the gas flow path. The signal from the main pressure sensor on the alarm line is unlikely to occur except when outdoor piping (steel pipe) is missing, so we will explain the signal from the bearing pressure sensor.

When gas is not used, (Tr 17) is activated, but since the pace voltage of (Tr 1B ) is O, (Tr 1B ) is activated.
18) The sumi pressure becomes O (Tr 17) and the operation is stopped. At the same time, the pace voltage of (Tr 18) rises (Trl
, s) will start operating, and the LBD blue) will light up to notify you that gas is being used. When it disappears (Trl8)
The pace voltage disappears and the light (LBD blue) goes out. In this state, the pace voltages of (Tr 10) and (Tr 11) are 0, so (Trlo) and (Trll) do not operate.

When the pressure inside (Fig. (1)) decreases and the voltage on the alarm line increases, the red LED lights up to notify you of a problem.

When gas is not used, the abnormal signal line (Trl
The pace voltage of 8) is O(Tr 17) (Trio)(
When the pace voltage of (Trll) rises and is activated, the electricity stored in the capacitor (C6) is squeezed by the resistance of (R25) and gradually flows through (Trll) to the pace of (Tr 12). 13)
The pace voltage becomes 0 and (Tr 13) stops operating. If the gas pressure in the gas flow path drops with the appliance valve closed (this means that there is a gas leak for some reason between the shutoff valve and the appliance valve), the voltage on the alarm line will drop. When the rising (Trt4) is activated, the pace voltage of (Trxs) is activated and the rising (Trl6) is activated and Tr20. )
(BZ) also operates and the buzzer sounds an alarm. At the same time (09,,'if the voltage starts, Zn2), when the operating voltage of the Zener diode is reached ('Tr15) starts operating, Trl6), the collector voltage becomes 0 (Tr20 stops operating, BZ), and the buzzer stops. The operating time of (B Z) is determined by the resistance (R29), the conde 7l-(09) and
) This device, which can be freely set by combining 7-ener diodes, tends to be too sensitive, and to alleviate this, the following steps are taken. Not all gas leaks will lead to accidents; the explosion range of propane is between 3 inches and 9 inches relative to the air, and the dangerous amount Q in a 4-5 tatami room when calculating the lower explosive limit is 0. 03V.

■ = Room volume -: 6.8 mF Q = 0.03
V Medium 0.2 m' = 200t is the lower limit of the dangerous amount, and with this device, it is unlikely that it will leak from the gas appliance, so if we think that it will leak from the hole in the conduit, the problem is the time it takes to reach the dangerous amount. Even if there is a leak other than when the shutoff valve is open, only the differential pressure inside the conduit leaks, and the amount of leakage is expressed by the following formula: πD
2 Next Lu a Lx<@HP 1,2501111AqD =
2 L 6ZL=(20^)201+1 (Z1
6m K ÷ 4) 20,000
Leakage below ot/h does not pose a danger. Therefore 1
．． 83÷50/60 = 1.525 minutes 20A20m
It is not dangerous if the differential pressure in the pipes leaks for more than 1.5 minutes in a home with plumbing. Therefore, if the safety factor of this device is set to 10 times or more and the (BZ) buzzer is activated within 15 minutes, it is necessary to immediately inspect the entire gas flow path. The operating time can be adjusted freely using the capacitor (C6) and the resistor (R25). (Tr 11) is activated and current flows from the capacitor (C6) via the resistor (R25) for 15 minutes (Tr 12) is activated. During that time, the gas pressure in the gas flow path drops and the voltage on the alarm line rises (Tr 12). 14
) is activated, BZ) buzzer sounds and (LED red) lights up at the same time. As soon as it goes out, the (IJD red) will light up.
rl2) and (Trl4) operate simultaneously and the BZ) buzzer operates. The gas flow path of this device must be inspected each time after use.

[Brief explanation of the drawing]

FIG. 1 is an assembly diagram of the expansion cutoff valve and pressure switch. FIG. 2 is an operational circuit diagram of the shutoff valve. FIG. 3 is a detailed view of the pressure switch. Figure (1) (1) Plunger receiver set screw (2) Plunger receiver (3) is a magnetic material and is used as a yoke rear plate to enhance the magnetic force of the coil, (4) yoke, (5) coil & yoke cover, (
6) Bobbin, (7) Coil, (8) Sleeve, (9) Plunger wiring holder, AN electric wire, A screw for installation, +13 yoke front plate, A40 ring, a! 9 spring, ae washer, aη disc holder, as disc, as disc holder set screw, co body,
aa sheet packkin. (To) Pressure sensor set grate, (To) Pressure top holder (Incorporated) wiring holder, @electric wire, c8 mounting 7 lunge, @
Installation is with screws. Diagram (2) Swearing signal line, cock signal twin, OOMAO28V
Power supply, wiring for the cutoff valve, (Tr8) Power transistor for operating the cutoff valve, (Tr9) is the t-run sister for driving (Tr8), (D7) (DB) is the diode for adjusting the cutoff valve overcurrent, (05) A capacitor that allows a large amount of current to flow through the shutoff valve during suction. (R24) Resistor for restricting the current flowing to the cutoff valve during suction (013) Rectifier diode. Figure (3). DC10V operating power supply, abnormal signal line, cock signal line, bearing pressure sensor signal line, main pressure sensor signal line (R32) (R33) (R34) Adjustment resistor (T
rlO) (LED blue) Switch transistor (T
r9) is the drive transistor (T
rlO) is a switching transistor (Tr12) for storing electricity in the capacitor (C6) when gas is used.
) is the drive transistor of (Tr13), (
Tr13) is the switching of (Tr14) and (Trl
(TrlO) is a switched transistor for driving O) and storing power to (C9) capacitor, (TrlO) is (TrlO).
20) switching relay, (Tr15) is (T
rlO) tie! -Relay, (R24) (R26)
(R27) (R31) (几3B) are adjustment resistors, (R25
) is (C6) the capacitor outflow current adjustment resistor (C6)
(Tr 12) drive timer, (D9) backflow prevention from (06). (DIO) prevents backflow of the base current of (Tr12), (
Dll) prevents backflow from the main pressure sensor to the bearing pressure sensor (R29') (R2g) is the FJ41i resistor, (Zn2) Zener diode is the (Tr15) evening
The timer can be adjusted freely by combining the resistor (R29) and capacitor (C9).
(BZ) Buzzer, (LED red) red indicator light, (LED blue) blue indicator light. Saiichi 1 Ya 2nd day I candy

Claims (1)

[Claims] B) Suction increase device and heat generation prevention device for solenoid shutoff valve B) Pressure sensor using strain gauge and leak detection gas flow path defect detection device