JPH0659328B2 - Gas shutoff device - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a gas shutoff device that ensures the overall safety of a gas supply.

2. Description of the Related Art In recent years, gas breakers have become small and low-cost due to the development of microelectronics, and have become popular in general households.

An example of the above-described conventional gas shutoff device will be described below with reference to the drawings. FIG. 2 shows a block diagram of a conventional gas shutoff device. In FIG. 2, 1 is a gas meter, 2 is a flow sensor attached to the gas meter 1, 3 is a diaphragm type pressure sensor attached to the gas meter 1, 4 is a control unit, and 5 is a self-holding cutoff of a gas passage leading to the gas meter 1. A valve (hereinafter referred to as a shutoff valve).

The operation of the gas shutoff device configured as described above will be described below. Gas flows as indicated by an arrow, and a gas flow rate signal is transmitted from the flow rate sensor 2 to the control unit 4. The control unit 4 operates the shutoff valve 5 to shut off the gas passage when the gas flow rate is abnormal or when a certain flow rate continues for an abnormal time. Further, the diaphragm type pressure sensor 3 detects the pressure drop on the downstream side due to the gas leakage of the meter, and the shutoff valve 5
To shut off the gas passage.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, there is a cock on the upstream side of the meter, and the number of people who stop this cock at night is increasing in recent consumers. When this cock is stopped, the pressure sensor operates, and the shutoff valve stops even if the pressure on the downstream side does not drop. When the gas shutoff device, which should operate as a safety device, shuts off when it is safe, it causes confusion for consumers. Further, if the control unit sensors fail, the shut-off valve may not operate because of the serial reliability configuration, which may cause a dangerous state.

Means for Solving the Problems In order to solve the above problems, the gas shutoff device of the present invention is
Instead of the diaphragm type pressure sensor of the conventional configuration,
On the downstream side of the self-holding shutoff valve in the gas passage, there are provided a valve seat, a sphere, a pressure valve in which the sphere is fixed by an elastic body, and a detection unit for detecting a variation of the sphere of the pressure valve and inputting it to a control unit. .

Operation According to the present invention, when the pressure on the downstream side of the meter is decreased due to the gas leakage, the sphere is pushed to the valve seat to stop the gas leakage. The pressure valve does not work even if the main cock is stopped. Further, the detection unit can notify the control unit of the pressure drop and stop the shutoff valve.

Embodiment A gas shutoff device according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a block diagram of a gas shutoff device in one embodiment of the present invention. In FIG. 1, the same numbers as those in FIG. 2 represent the same items, and are functionally the same as the conventional example. 6 is a sphere having a magnet embedded therein, and 7 is a spring as an elastic body, one of which is fixed to the inner wall of the meter, and one of which has a sphere 6. 8 is a valve seat. 9
Is a detector for detecting the position of the magnetic field of the sphere 7, and a reed switch is used here. Reference numeral 10 is a pressure valve composed of a sphere 6, a spring 7, and a valve seat 8.

The operation of the gas shutoff device configured as described above will be described below with reference to FIG. When there is a pressure drop on the downstream side due to gas leakage, the sphere 6 hits the valve seat 8 against the force of the spring 7 and automatically shuts off the gas. Further, the reed switch 9 informs the control unit 4 that the pressure has dropped due to the fluctuation of the sphere 6, shuts off the shutoff valve 5 and shuts off the gas passage. According to this, even if the control unit is out of order, the gas passage is shut off by the pressure valve, so that the configuration becomes parallel and reliability is increased. Further, even if the main cock is stopped, the pressure valve does not work, and it does not malfunction like the conventional diaphragm type pressure sensor.

Effects of the Invention The effects of the present invention as described above will be described below.

(1) Compared with the conventional diaphragm type pressure sensor, a parallel structure of a shutoff valve and a pressure valve can be adopted as a function of shutting off the gas passage, and the reliability of the gas shutoff device can be improved.

(2) There is no malfunction due to stopping the original cock,
It can prevent consumer confusion.

(3) Although the diaphragm type pressure sensor and pressure valve have the same final function, the diaphragm type must maintain tightness with the gas passage, which may cause gas leakage. The pressure valve is completely independent of the gas passage and the detector, so there is no risk of gas leakage and reliability is improved.

[Brief description of drawings]

FIG. 1 is a block diagram of a gas shutoff device in one embodiment of the present invention, and FIG. 2 is a block diagram of a conventional gas shutoff device. 2 ... Flow rate sensor, 4 ... Controller, 5 ... Shut-off valve, 6 ...
... sphere, 7 ... elastic body, 8 ... valve seat, 9 ... detector, 1
0 ... Pressure valve.

Claims (1)

[Claims] 1. A gas flow rate sensor and a self-holding shutoff valve provided in a gas passage, a control unit for controlling the shutoff valve in response to a signal from the flow sensor, and a self-holding shutoff valve for the gas passage. A gas cutoff device comprising a valve seat, a sphere, a pressure valve in which the sphere is fixed to an inner wall of a gas passage by an elastic body on the downstream side, and a detection unit which detects a variation of the sphere of the pressure valve and inputs the variation to the control unit.