JPS5838207Y2 - gas fire safety valve - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention mainly relates to a gas fire extinguishing safety valve that shuts off a gas passage by a signal from a flame detection means when a gas combustion appliance goes out.

Conventional configuration and its problems A combustion safety device that automatically shuts off the gas circuit and prevents raw gas from flowing out in the event of a misfire or abnormal combustion in a gas appliance is equipped with a combustion safety device that prevents raw gas from flowing out. There is a safety valve that uses the attraction force of an electromagnet excited by an electromotive force.

Figure 4 shows a conventional example of this safety valve.
A fixed iron core 2 consisting of an electromagnet wound with an excitation coil 1 (not shown) and a movable iron core 3 consisting of an adsorption disk are housed facing each other in a casing 5 fixed to a base 6, and the movable iron core Reference numeral 3 has a disk shape with a uniform plate thickness, has a support hole 16 in the center, is swingably attached to one end of the rod 7, and is a spring 10 provided between the housing 5 and the valve body 9. is biased against the attraction force of the electromagnet.

In such a conventional safety valve, the movable core 3 has a disk shape with uniform plate thickness, and is supported by the rod 7 with a sufficient margin through a support hole 16 provided in the center. 4, housing 5, rod 7, valve body 9, spring 10
Since the operating shaft 11 is often used with its center axis X-X substantially horizontal, vibrations occur when the iron core adsorbs and detaches, or when the gas appliance is ignited, the gas cock has a structure in which the operating knob is pushed and rotated (Fig. (not shown), the movable iron core 3 rotates around the X-X axis due to the push-and-turn operation, and even if the movable iron core rotates to a position rotated by a certain angle from the initial position,
Since no force is generated to return it to its original position, the mutual positional relationship between the fixed and movable cores changes.

The surface roughness of both fixed and movable iron cores is generally 4 to 9.
It is precisely finished to μm (wrapping process),
During adsorption, the contact surfaces of both eyes further improve surface roughness, improve adhesion, and require less adhesion force as indicated by adsorption current or adsorption voltage.

In other words, with the push-and-turn type fire extinguishing safety valve, the suction holding time is maintained at the level set at the time of design.

However, in the conventional structure shown in Fig. 4, the mutual positions of the fixed and movable cores change depending on the state of use, and some surfaces frequently come into contact with the suction surface on the movable core side while others rarely come into contact with each other. If there is a difference in level between the surfaces, or if a slight amount of rust occurs on the surfaces that rarely come into contact, the degree of adhesion between the two suction surfaces will deteriorate, causing problems such as poor suction with normal suction current. there were.

Technical Problem of the Invention The technical problem of the invention is to maintain the surface roughness of the suction surface of the movable iron core at a level higher than the initial level and to prevent deterioration of the suction surface during repeated use.

Technical means of the invention The technical means taken to solve the above problem is that when the movable core and rod are supplied in a flexible state, the relative position of the movable core with respect to the horizontally placed rod is always constant. In this way, the center of gravity of the movable iron core is offset downward from the center of the support hole in which the movable iron core is supported.

Effect of technical means Since the movable core is flexibly connected to the horizontally placed rod, the heavy side of the movable core is always at a lower position with respect to the rod, and is attached to the suction surface of the fixed core. The opposing suction surfaces of the movable core can be limited.

Unique Effects of the Invention According to the invention, as the number of times of use increases, the lapping process is repeated between the binocular attachment surfaces, and the degree of surface roughness of both adsorption surfaces reaches or exceeds the initially set level. The suction retention time is stabilized and rust is less likely to occur on the suction surface.

Description of the first embodiment A first embodiment of the present invention will be described below.

Reference numeral 1 denotes an excitation coil wound around a fixed iron core 2 provided substantially horizontally, and 3 a movable iron core in the form of a disk with uniform plate thickness, which has a support hole 4 at a position eccentric from the center.

Reference numeral 5 denotes a casing fixed to a base 6, in which a fixed iron core 2 and a movable iron core 3 are housed facing each other.

7 is a rod to which a valve body 9 for closing a valve seat 8 is connected to one end, and a movable iron core 3 is swingably attached to the other end and is provided almost horizontally; A spring provided between the valve body 9 and the valve element 9 is biased to resist the attraction force of the electromagnet.

Reference numeral 11 denotes an operating shaft for opening the closed valve seat 8, which is linked to the movement of a gas cock (not shown) when igniting a gas appliance.

The connecting portion between the movable core 3 and the rod 7 is formed by inserting a step 13 of the rod 7 into a hole 4 eccentrically provided in the movable core 3 so that the opening diameter on the suction surface 12 side is larger than the opening diameter on the rod 7 mounting side. The movable iron core 3 is swingably connected to the rod 7 by inserting an end portion having a diameter and expanding the end portion, and by the holding portion 14 and the step 13.

With the above structure, the eccentric movable iron core 3 of the support hole 4 is stably supported with respect to the horizontal rod 7 in a position where seven points are always below.

Therefore, even if the rod 7 is rotated by pushing and turning the operating shaft 11, the portion of the suction surface 12 of the movable core 3 that is suctioned to the suction surface of the fixed iron core 2 does not change during suction.

Therefore, the contact positions of the attracting surfaces of both iron cores are determined, and a safety valve with stable characteristics with little change in operating current even after repeated use can be obtained.

In this embodiment, the movable iron core 3 has a uniform thickness, so it is easy to process.

Explanation of Second Embodiment FIGS. 3A and 3B show another embodiment, in which a support hole is provided in the center of a disk-shaped movable iron core 3, and a convex portion 15 is locally thickened.
It has been established.

The position of the center of gravity G of the movable iron core is offset with respect to the support hole.

If this is done, the two points will always be at the bottom, similar to the first embodiment.

In this embodiment, there is no need to change the dimensions (outer diameter) of the movable core 30 from the conventional one, and the valve body can be used with almost the conventional structure, which is advantageous in terms of design.

[Brief explanation of drawings]

Figure 1 is a sectional view of a gas fire safety safety valve that is an embodiment of the present invention, Figure 2 is an enlarged side view of the movable iron core used in Figure 1, and Figure 3 is an enlarged side view of the movable iron core used in Figure 1.
Figures A and B show other embodiments of the present invention, where A is an enlarged sectional view, B is an enlarged side view, Figure 4 is a sectional view of a conventional gas fire safety safety valve using a movable core, and Figure 5. is an enlarged side view of the movable iron core. 2... Fixed iron core, 3... Movable iron core, 4
...Support hole, 7...Rod.

Claims (2)

[Scope of utility model registration request] (1) A fixed core that forms a suction surface substantially perpendicular to the horizontal axis, a movable core that is removably attached to the suction surface of the fixed core, and has a closing valve body such as a valve seat at one end and the other end. and a rod flexibly connected to the movable iron core and located approximately horizontally, the center of the support hole of the movable iron core supported by the rod and the center of gravity of the movable iron core being eccentrically formed. A gas fire safety valve configured to (2) The scope of the utility model registration term described in item 1, which is configured such that the plate thickness of the movable iron core is locally changed so that the center of gravity of the movable iron core and the center of the support hole of the movable iron core are eccentrically formed. Gas fire safety valve.