JPS5938685Y2 - pressure safety valve - Google Patents

Description

[Detailed description of the invention] The present invention relates to a pressure safety valve used in an instantaneous water heater, etc., and this will be specifically explained based on an embodiment of the drawing. 1 is the instantaneous water heater main body; , has a heat exchanger 2 and a gas burner 3 inside.

4 and 5 are water inlet pipes and hot water outlet pipes connected to the heat exchanger 2;
The inlet pipe 4 is provided with a water stop valve 6, and the outlet pipe 5 is provided with a water supply valve 7.

8 is a gas supply pipe leading to the gas burner 3, and a thermoelectric ignition safety valve 9 and a main valve 10 are provided in this order from upstream.

11 is a pilot gas supply pipe leading to a pilot burner 12, and a pilot valve 13 is provided.

14 is a thermocouple facing the pilot burner 12;
It is connected to an electromagnet 15 that controls opening and closing of the thermoelectric ignition safety valve 9.

16 is a hydraulic response device that opens and closes the main valve 10.

17 is the main valve.

18 is an operating shaft for opening and closing the thermoelectric ignition safety valve 9, the main valve 17, and the pilot valve 13.

Reference numeral 19 is a Japanese drawing of a pressure safety valve installed at a suitable location in the hot water outlet pipe 5 close to the heat exchanger 2, including a pressure receiving port 20 communicating with the hot water tapping pipe 5, and a communicating port 2 provided opposite to this pressure receiving port 20.
7 and a drain port 21 are formed.

22 is a small diameter passage communicating with the pressure receiving port 20, and 23 is a drain port 2.
1, and these two passages 22.2
3 is provided concentrically and continuously.

24 is a valve body consisting of a rond arranged within the valve surface 19;
Attach the 01J ring 25 to the circumferential side of the tip and attach the spring 26.
The O-ring 25 is fitted into the small-diameter passage 22 and urged in a direction to close the small-diameter passage 22, and its rear end faces the communication port 2T.

28 is a switch 3 consisting of a pressure receiving chamber 30 communicating with the communication port 27 through a diaphragm 29 and a movable point of a fixed contact a1.
This is a switch box divided into a chamber 32 having 1.

The switch 31 is connected to the circuit of the thermocouple 14.

Since the present invention is constructed as described above, its operation will be explained next. First, the operating shaft 18 is operated appropriately to open the thermoelectric ignition safety valve 9 and the pilot valve 13, and the jet is emitted from the pilot burner 12. Ignite the gas using some means.

Since the thermocouple 14 is heated by the pilot flame, the electromagnet 15 is energized and the thermoelectric ignition safety valve 9 is attracted and held in the open state.

Here, when the operating shaft 18 is further rotated to open the main valve 17 and then the water supply valve 7 is opened, the hydraulic response device 16 is activated and the main valve 10 is opened, and the pilot flame ignites the gas burner 3. The main combustion starts, and the water supply valve 7
Hot water is supplied from the ground.

Here, if the water supply valve I is closed, the hydraulic response device 16 will no longer operate, so the main valve 10 will be closed and the gas burner 3 will be extinguished.

However, since the pilot burner 12 continues to burn, if it is left in this state for a long time, the pilot flame will cause the residual hot water in the heat exchanger 2 to gradually post-boil. As the pressure rises, the valve body 24 is pressed against the spring 26, and the O-ring 25 comes off the small diameter passage 22 and reaches the large diameter passage 23, and the OI
Since there is a gap between the J-thong 5 and the peripheral wall of the large-diameter passage 23, hot water is allowed to escape through the drain port 21.

In this case, since hot water does not suddenly flow into the valve surface 19,
It does not flow into the pressure receiving chamber 30 from the communication port 27, but is entirely discharged from the drain port 21 as described above.

Therefore, even if the pilot flame is not extinguished, the heat exchanger 2
This will prevent pressure build-up within the vehicle and ensure safety.

Furthermore, even if the water supply valve I is closed, the main valve 10 may not be closed due to a failure of the hydraulic response device 16, etc. At this time, the gas burner 3 continues to burn, so the pressure inside the heat exchanger 2 suddenly increases. The valve body 24 is pressed and the pressure receiving port 20 is opened, and the pressure inside the valve surface 19 rises rapidly. Pressure is applied in the pressure receiving chamber 30 from the above, pushing the diaphragm 29 and opening the switch 31.

Therefore, the circuit of the thermocouple 14 is opened, the electromagnet 15 loses its magnetic force, the thermoelectric ignition safety valve 9 is closed, the combustion of the pilot burner 12 and the gas burner 3 is stopped, and the heat exchanger 2 is emptied. Fires can be prevented in advance.

In this way, the present invention disposes a valve element biased toward the pressure receiving port by a spring on the valve surface that forms the pressure receiving port, drain port, and communication port that communicate with each other, and a thermocouple is attached to the communication port. A member is provided to open and close the switch connected to the circuit, so that the valve body normally closes the pressure receiving port, and when the pressure rises, the valve body is pressed against a spring to unblock the pressure receiving port. Therefore, if the pressure inside the heat exchanger gradually increases due to after-boiling caused by the pilot flame, the pressure (hot water) will be released from the drain port, ensuring safety. Since the water itself does not disappear, it can be reused by opening the water supply valve.

In addition, if the pressure rises rapidly, such as when the stove is almost empty, pressure (hot water) will also be applied to the communication port, causing the component to act and open the switch, stopping the gas supply. Therefore, dry heating can be prevented.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention. Fig. 1 is an overall configuration diagram during normal operation, Fig. 2 is a sectional view of the pressure safety valve when the pressure rises slowly, and Fig. 3 shows the pressure relief valve when the pressure rises rapidly. FIG. 3 is a sectional view of the pressure safety valve in the case of 14... Thermocouple, 19... Valve surface, 20
......Pressure port, 21...Drain port, 24...
...Fore body, 26... Spring, 2T...
Communication port, 29... member, 31... switch.

Claims (1)

[Scope of utility model registration request] A pressure receiving port that communicates with water heaters, etc., is installed in the Japanese movie.
A small-diameter passage communicating with the pressure-receiving port and a large-diameter passage concentrically continuous with the small-diameter passage are provided, and a pressure-receiving chamber and a drain port that are constantly in communication with the large-diameter passage are formed in a Japanese film, and on the circumferential side of the tip. The valve body with the 0-ring attached is constantly urged by a spring toward the pressure receiving location so that the 0-ring fits into the small diameter passage, and the small diameter passage is closed by the 01J ring.
A pressure safety valve characterized in that each of the large diameter passages is provided so as to create a gap between the QIJ songs, and a diaphragm for opening and closing a switch connected to an electric circuit faces the pressure receiving chamber.