JPH0112041Y2 - - Google Patents

Description

[Detailed description of the invention] The invention is such that the valve body is separated from the valve seat via a plunger that is attracted by electricity, and the separated state is maintained by an electromagnetic device that is excited by thermoelectromotive force. This paper relates to improvements to solenoid valves.

This type of solenoid valve can be suitably used, for example, as a flame safety device for gas appliances, but conventional ones are designed to use commercial power as a power source to draw the plunger, so they are large in size. Not only is it relatively expensive, but when installed in the kitchen of an existing house, it is often necessary to use octopus wiring due to a lack of electrical outlets, resulting in safety problems.

In view of these circumstances, the present invention allows the ignition battery of a gas appliance to be used as a power source to attract the plunger, and eliminates the influence of residual magnetism when the valve is closed, resulting in smooth operation. The object of the present invention is to provide a solenoid valve of this type that is small and can be manufactured at low cost.

Hereinafter, this will be explained based on an illustrated embodiment. 1 is a gas inlet 1a, a valve seat 1b, and a gas outlet 1.
2 is an outer yoke airtightly attached to the main body 1; 3 is a bobbin attached to the outer yoke 2 and wound with an excitation coil 3a; 4 is fitted inside the bobbin 3; 5 is an O-ring for maintaining airtightness between the bobbin 3 and the sleeve 4, and 6 is fitted inside the bobbin 3 and the sleeve 4. and the lower end is the outer yoke 2
A more protruding inner yoke; 7 is an O-ring for maintaining airtightness between the sleeve 4 and the inner yoke 6; 8 is placed on the inner yoke 6 with a spacer 9 made of a non-magnetic material interposed therebetween; A U-shaped core 11 made of a material with extremely low residual magnetism such as permalloy is fixed to the inner yoke 6 by an eyelet 10 fitted into a through hole in the bottom, and one end is wound around the core 8. An excitation coil 12 is welded to the inner yoke 6 and the other end 11a is inserted through the eyelet 10 and drawn out to the outside.
13 is a plug for electrically insulating the inner yoke 6 and the connection terminal 14; 14 is the plug 1;
2 and the packing 13 to be supported within the inner yoke 6, and the externally protruding end is the end 11a of the excitation coil 11.
The connection terminal 15 is integrally welded with the sleeve 4.
A cylindrical plunger whose upward movement range is limited by a cap 16 that is slidably fitted inside the sleeve 4 and whose upward movement range is limited by a cap 16 that is slidably fitted inside the sleeve 4; 17 is a valve that is slidably inserted into the plunger 15; bar, 18
19 is a valve element attached to the upper end of the valve stem 17 and can seat on the valve seat 1b to cut off communication between the gas inlet 1a and the gas outlet 1c; 19 is the valve element 18 and the cap 16;
The valve body 18, that is, the valve stem 1, is interposed between the
a coil spring 20 that presses 7 in the valve closing direction;
is movably attached to the lower end of the valve stem 17 within the inner space of the plunger 15, is movable relative to the plunger 15, and is a residual material such as permalloy that can be attracted to the core 8 when the core 8 is excited. The arming plate 21 made of a material with extremely low magnetism is a thermocouple that is installed near the burner of a gas appliance (not shown), and one of a pair of conductive wires can be connected to the terminal 11a and the other to the inner yoke 6.
In this case, the core 8, the plunger 15, and the valve stem 17 are arranged concentrically, and in the non-operating state shown in the figure, the valve body 18 is in the closed position due to the elasticity of the spring 19, and the plunger 15 is in the closed position. 20 and is pulled up to the upper extreme position. Furthermore, the elasticity of the spring 19 is selected to be smaller than the attraction force of the plunger 15 caused by energizing the excitation coil 3a, as well as the attraction force of the electromagnetic device consisting of the core 8 and the excitation coil 11. . Furthermore, even when the plunger 15 is attracted and reaches the lowest position corresponding to the position where the armature plate 20 contacts the core 8 as shown by the chain line, the plunger 1
The relative positions of the two are selected so that the lower end edge of the inner yoke 5 does not come into contact with the upper end edge of the inner yoke 6.

Since the proposed solenoid valve is constructed as described above,
When an ignition device (not shown) is activated to ignite the burner, power is supplied from the power battery to the excitation coil 3a in the initial stage, and the plunger 15 is attracted toward the inner yoke 6. Due to this downward movement of the plunger 15, the armature plate 20, valve rod 17, and valve body 18 are lowered together against the spring 19, and the gas passage is opened and gas is supplied to the burner. Ignition is achieved by a spark generated by an ignition device. At this time, the armature disc 20 comes into contact with the core 8, but the armature disc 20 is attached so that it can move freely within a certain range relative to the valve stem 17, and is also movable relative to the plunger 15. At the stage when the adsorption force generated between the armature plate 20 and the core 8 due to the thermoelectromotive force that gradually increases due to the heating of the thermocouple 21 becomes larger than the elasticity of the spring 19, the plunger 15 and the valve stem 17 are slightly bent. The armature plate 20 is independent of the deviation in posture.
completely adheres to the top surface of the core 8. Therefore, even if the battery circuit is opened and the energization to the excitation coil 3a is stopped at this stage, the gas passage continues to be kept open, so that consumption of the power source battery can actually be suppressed to a minimum. Thus, when the burner needs to be extinguished, the thermocouple circuit can be opened. That is,
If the thermocouple circuit is opened and the supply of thermoelectromotive force to the electromagnetic device is stopped, the adsorption force between the armature plate 20 and the core 8 disappears, and therefore the plunger 15 and the valve stem 1
7. The valve body 18 and the armature plate 20 are returned together to the illustrated position by the elasticity of the spring 19, and the gas passage is blocked. Also, if the flame of the burner goes out for some reason, the thermoelectromotive force decreases and the polarization plate 2
Since the adsorption force between the core 8 and the core 8 becomes smaller than the elasticity of the spring 19, the gas passage is blocked as in the case described above. Therefore, it can also function as a gas safety device. In the above case, the core 8 and the armature plate 20 are made of a material such as permalloy with extremely low residual magnetism, and the core 8 is mounted on the inner yoke 6 via a spacer 9 made of a non-magnetic material. Furthermore, since the plunger 15 and the inner yoke 6 do not come into contact with each other, even if the spring load of the spring 19 is selected to be small, the polarization plate 2 when the valve is closed.
The break from the core 8 of 0 is extremely sharp, and it is possible to eliminate waste of gas when closing the valve.

As described above, according to the present invention, the structure allows the arming plate and the electromagnetic device to be installed within the inner space of the plunger, so the entire electromagnetic valve can be made extremely compact and compact, and moreover, the valve can be closed easily. Eliminates the influence of residual magnetism during operation, resulting in sharp cutting edges.
This type of solenoid valve can be provided at extremely low cost.

[Brief explanation of the drawing]

The drawing is a longitudinal sectional view of the electromagnetic valve according to the present invention in a closed state. 1...Solenoid valve body, 1a...Gas inlet, 1b...
... Valve seat, 1c... Gas outlet, 2... Outer yoke,
3... Bobbin, 3a... Exciting coil, 4... Sleeve, 6... Inner yoke, 8... Core, 9... Spacer, 11... Exciting coil, 15... Plunger, 17... Valve stem, 18 ...Valve body, 20...Archive plate, 21...Thermocouple.

Claims (1)

[Claims for Utility Model Registration] (1) The valve body is separated from the valve seat via a plunger that is attracted by electricity, and the separated state is maintained by an electromagnetic device that is excited by thermoelectromotive force. In a solenoid valve, a valve stem is inserted into a plunger so as to be relatively slidable in the direction of movement thereof, a valve body is attached to one end of the valve stem, and the other end is capable of engaging with the plunger and moves within the inner space of the plunger. The electromagnetic device is attached to an inner yoke disposed opposite to the plunger via a spacer made of a non-magnetic material, and the armature plate is attached to the armature plate made of a material with low residual magnetism. It consists of a core made of a material with low residual magnetism and an excitation coil that is wound around the core and can be connected to a thermocouple, and when the armature plate is attracted to the core, the plunger and the inner yoke are separated. A solenoid valve characterized in that the distance between the plunger and the inner yoke is set as shown in FIG. (2) The solenoid valve according to claim (1) for utility model registration, in which the armature plate is movably attached to the valve stem. (3) The solenoid valve according to claim (1) or (2), in which the armature plate and the core are made of permalloy.