JPS636546Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a structure for mounting a valve body in a solenoid valve for a spark safety device.

Fig. 1 schematically shows the basic structure of the safety device. In the figure, 1 is the main body including the gas passage 1a and the valve seat 1b, and 2 is the valve seat 1b. A valve body capable of opening and closing the passage 1a, 3 a valve stem with the valve body 2 attached to its upper end, 4 a cylindrical case installed in the gas passage and into which the valve stem 3 is slidably inserted, and 5 a valve. A spring is interposed between the body 2 and the cylindrical case 4 and presses the valve body 2 in the valve closing direction; 6 is an iron piece fixed to the lower end protruding into the cylindrical case 4; 7 is a spring; An electromagnet installed in the cylindrical case 4 and capable of attracting and holding the iron piece 6 when excited; 8 is a thermocouple for exciting the electromagnet;
9 is a pilot burner installed at a position where it can heat the thermocouple 8; 10 is slidably fitted into the main body of the valve, the lower end of which can come into contact with the upper end of the valve stem 3, and is seated on the valve seat portion 1b; The push rod 12 having the auxiliary valve body 11 is a spring that presses the auxiliary valve body 11 in the valve opening direction, and its operation is as follows. That is, if the push rod 10 is pushed against the spring 12 to ignite the pilot burner 9,
The auxiliary valve body 11 is seated on the valve seat 1b and continues to block the gas passage 1a, while the valve body 2 is separated from the valve seat 1b and the iron piece 6 is brought into contact with the electromagnet 7. This operation opens only the gas passage to the pilot burner 9, so if the ignition device is activated at the final stage of pressing the push rod 10 to ignite the pilot burner 9, a pilot flame is formed and the thermocouple 8 is heated. be done. Therefore, when the push rod 10 is continued to be pressed for a predetermined time, a thermoelectromotive force of a predetermined magnitude is generated in the thermocouple 9, and the electromagnet 7 penetrates the spring 5 to attract and hold the iron piece 6.
Even when the pressure is released, the valve body 2 is maintained at the valve open position. Therefore, the gas passage 1a is opened and the main burner is ignited. If the pilot flame is extinguished in this state, the thermoelectromotive force is extinguished and the valve body 2 is rapidly moved to the closed position by the spring 5, so that the main burner flame is also extinguished automatically.

As can be understood from the above explanation, if the calorific value of the gas appliance is small and the safety device is small, the diameter of the gas passage and valve seat will be small, the electromagnet will also be small, and the adsorption force will be small. Therefore, the spring 5 must also be weakened. On the other hand, the valve stem 3 has a certain degree of strength ( It can only be made as thin as 3 to 4 mm in diameter. By the way, the valve body of this kind of conventional solenoid valve is shown in Figs. 2 and 3.
As shown in the figure, it is constructed by fitting a flat or chevron-shaped sheet 202 made of a suitable sealing material such as hard rubber into a metal holder 201, and these are attached to the upper end of the valve stem 3. It was attached to the valve stem 3 by inserting it tightly and stopping it with a C-ring 203 etc. fitted to the valve stem 3, but in any case, the head of the valve stem 3 or the C-ring was attached to the seat 202. Because the seat 202 protrudes from the seating surface of the valve body, its head may come into contact with the wall surface of the valve seat gas passage or the valve seat portion 1b when seated due to center runout. Due to the partial contact with the valve seat surface and the weak elasticity of the spring 5, the gas passage could not be reliably shut off when the valve was closed. As described above, the mounting structure of the valve body in the conventional electromagnetic valve has been difficult to achieve miniaturization.

In order to solve the problems of the conventional structure, the present invention is attached to the valve stem so that the tip end surface of the valve stem is recessed from the seating surface of the valve body. Specifically, with reference to the embodiment shown in FIG. 5, whether the sheet 202 is flat or chevron-shaped,
02 is depressed inward from the seating surface and the seat 202 is tightly fitted to the tip of the valve stem 3.
The distal end surface of the valve stem 3 is configured to be buried inside the seat 202 by a distance a from the seating surface of the seat 202.

Therefore, even if the valve rod 3 rises in a state of eccentricity when the valve is closed, its tip will not come into contact with the side wall of the valve seat hole, so the seating surface of the seat 202 will be uniform on the valve seat portion 1b. Even if the elasticity of the spring 5 is relatively weak, the gas passage can be reliably blocked. Also, when the valve is opened, the valve stem 3 and push rod 1
Even if the seat 202 and the seat 202 come into contact with each other in an eccentric state, the seating surface of the seat 202 will not be damaged.

As described above, according to the present invention, even if a small valve body is used, the gas passage can always be reliably shut off, so it is possible to provide a small spark safety device at a low cost.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram for explaining the basic structure of a spark safety device, and FIGS. 2 and 3 are enlarged partial views showing a conventional example of the mounting structure between the valve body and valve stem of a solenoid valve for a spark safety device. 4 and 5 are enlarged partial views showing the mounting structure of the valve body and valve stem according to the present invention. 1...Kotsuku body, 1a...Gas passage, 1b...
... Valve seat, 2... Valve body, 201... Holder, 2
02... Seat, 3... Valve stem, 5... Spring, 6... Iron piece, 7... Electromagnet, 8... Thermocouple,
9... Pilot burner, 10... Push rod.

Claims (1)

[Scope of utility model registration request] A valve body that can be seated on a valve seat inside the cockpit body, that can hold the gas passage in the cockpit body in an open state by an electromagnet excited by thermoelectromotive force generated by the pilot flame, and can shut off the gas passage when the pilot flame disappears. In the solenoid valve for spark safety, including the valve body, the valve body whose central part is recessed inward from the seating surface is directly fixed so that the tip surface of the valve stem is in a position recessed from the seating surface of the valve body. A solenoid valve for a spark safety device, which is characterized by being attached to a valve stem.