JPH0483984A - Shut-off valve - Google Patents

Abstract

PURPOSE:To perform remote control of a return device and to perform operation to shut off gas even during lock of the return device by bringing a valve body into contact with a valve seat through energization to a coil to shut off a gas passage. CONSTITUTION:A spring support 13 disposed to an end 7c of a plunger 5 of a core 7 energizes the core 7 in a direction in which the core is spaced away from a valve seat l. A second spring 14 is located in a state to be compressed between a first yoke 6 and the spring support and has a reaction force higher than that of a first spring 12. At a moment when a valve is closed, a current is applied on a coil 11 so that a magnetic field in a reverse direction is generated, an attraction force F is reduced to a value lower than a reaction force (f) of the first spring 12, the plunger 5 is separated away from the core 7, and a valve body 4 makes contact with the valve seat l to bring it into a closed state. In this case, the core 7 is energized in a reverse direction to the direction of the reaction force (f) through the force of the first spring 12 by means of a reaction force fs of the second spring 14 and forced into a rest state and held. This constitution shuts off a gas passage even when the shut-off return device of an external means is in a locked state and maintains safety to improve reliability.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a shutoff valve used as a gas shutoff mechanism of a gas shutoff device for preventing gas accidents.

BACKGROUND OF THE INVENTION Various types of safety devices have been used to prevent gas accidents, and gas shutoff devices that detect abnormal gas usage, gas leaks, etc. and shut off the gas are attracting attention. Especially in recent years,
Gas meters are now equipped with microcomputer gas cutoff devices that monitor the flow rate of gas using a flow rate sensor, determine abnormal usage conditions of the gas using a microcomputer, and cut off the gas using a gas cutoff mechanism. The microcomputer gas cutoff device is powered by a battery tS, and is a self-holding electromagnetic cutoff valve that applies current only at the moment of valve closing to reduce battery consumption, and does not require energy to maintain the valve closed or opened. Mainly used.

Generally, a conventional shutoff valve has a structure as shown in FIG. A valve body 42 faces the valve seat 41 and seals gas by contacting the valve seat 41, and a plunger 43 has the valve body 42 fixed to one end and moves in the axial direction due to a balanced relationship between magnetic force and spring biasing force. A spring 44 that urges the plunger 43 in a direction in which the valve body 42 approaches the valve seat 41
a yoke 45 disposed outside the plunger 43; a core 46 with one end fixed to the yoke 45 and the other end contactable with the plunger 43; The plunger 4
3, the core 46, and the yoke 45, and a permanent magnet 47 that generates a magnetic force in a direction that attracts the plunger 43 and the core 46; Has a movable insertion hole,
Coil 4 that excites the magnetic circuit by applying current
It consists of 8. Further, in order to return the plunger 43 and the core 46 by suction, a return shaft 49 of a return device attached to a gas meter or the like for pushing back the plunger 43 is disposed at the center of the valve seat 41.

The operation of this cutoff valve will be explained below. In the open holding state where the shutoff valve is open, the plunger 43 and the core 46 are attracted by the attraction force F created by the magnetic flux Φ due to the magnetomotive force of the permanent magnet 47 against the reaction force f of the spring 44.
The valve remains open. Next, at the moment of valve closing operation,
The coil 4 generates a magnetic field in the opposite direction to the permanent magnet 47.
8 is applied from a battery (not shown), and the adsorption force F decreases to become smaller than the reaction force f of the spring 44. This causes the valve to lose its balance and the plunger 43 separates from the core 46, causing the valve seat 41 to become unbalanced. The plunger 43 moves to a position where the valve body 42 comes into contact with and stops moving, and the valve is in a closed state.

In the valve closed state, the plunger 43 and the core 46
are sufficiently far apart and the attraction force F by the permanent magnet 47 becomes zero in the near future. Therefore, the reaction force f of the spring 44 keeps the valve body 42 in the position where it is in contact with the valve seat 41, and the valve body 42 is closed to seal the gas. The state of valve holding is maintained. Valve seat 41 and valve body 42
When the valve is opened and the shutoff valve is returned to the open state, an external load F0 is applied to the return shaft 49, and the return shaft 49 moves in a direction that contacts the plunger 43 and further pulls the valve body 42 away from the valve seat 41. During the plunge, a force F0 in the opposite direction that is greater than the reaction force f of the spring 44 is applied to the plunger 43, the plunger 43 moves and comes into contact with the core 46, and the attraction force F by the permanent magnet 47 is again greater than the reaction force f of the spring 44. Since it becomes larger, it is held by the core 46 by suction, and even after the force F0 is removed, the suction state is maintained and the valve open state is maintained.

FIG. 7 shows the structure of another conventional example. In the conventional shutoff valve shown in FIG. 7, when the valve returns from the closed state to the open state, an external load F is applied to the tension pawl 50 and the head of the pin 51 fastened to the plunger 43 moves. the plunger 4 in such a way that it makes contact with the
3 is applied with a force greater than the force of the spring 44, the plunger 43 moves and contacts the core 52 to open the valve. At this time, the attraction force by the permanent magnet is applied to the spring 44 again.
The plunger 43 is held by the core 52 by adsorption, and the valve is maintained in an open state through which gas can pass even after the external load F is removed.

Problems to be Solved by the Invention However, with the above configuration, it is necessary to go to the location where the gas meter is installed and manually operate the return shaft 49 and tension pawl SO when opening the cutoff valve that operates the return device.

In addition, due to an accident due to malfunction of the return device or a child's mischief, the shutoff valve may be damaged by an external load F on the return shaft 49 and the tension claw 50.
When the valve is locked in the open state with F applied, the valve body 42 cannot move toward the valve seat 41 even if the microcomputer gas cutoff device is required to operate. There was a problem that it could not be shut off.

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, it is an object of the present invention to enable remote control of a return device and to perform a gas cutoff operation even when the return device is locked.

Means for Solving the Problems In order to achieve the above object, the first means of the present invention is to provide a magnetic formation means that forms magnetic circuits in opposite directions by energizing a permanent magnet and a coil, and this magnetic formation means. A plunger and a core are housed in the core and slide on a common axis, and the plunger is fixed to the middle end of the plunger that protrudes from the magnetic forming means, is biased via a first spring, and is in contact with the valve seat facing the magnetic forming means. A valve body that contacts the valve body to shut off the gas passage, a core that is urged in a direction opposite to the plunger by the magnetic formation means via a second spring and protrudes, and an external means for returning the core into the inside of the magnetic formation means. It is something.

Further, a second means of the present invention includes a core screw-fitted to the magnetic forming means, and an electric drive unit that rotates this core and moves it coaxially with the plunger.

Effect: According to the first means described above, the shutoff valve of the present invention can prevent the valve body from coming into contact with the valve seat by energizing the coil, so that even if the external means is locked with the core returned inside the magnetic forming means, the valve body comes into contact with the valve seat and the gas is released. Passages can be blocked.

Further, according to the second means, in the shutoff valve of the present invention, the electric driving section is operated by the receiving section of the gas shutoff device that receives an electric signal for operating the shutoff valve from a remote location, and shuts off the gas passage.

Example Embodiments of the present invention will be described below based on the accompanying drawings.

The valve seat and flange 2 of the first embodiment of the shutoff valve shown in FIG.
is airtightly fixed in the gas passage 3, has a valve body 4 facing the valve seat 1, has the valve body 4 fixed to one end 5a, and is a rod-shaped magnetic body that moves in the axial direction due to the balance between magnetic force and spring biasing force. A plunger 5 made of Other end 5 of plunger 5
A first yoke 6 made of a magnetic material and having an insertion hole 6a coaxially with the
is supported by the flange 2, the end 7a with a narrow outer diameter is inserted into the insertion hole 6a of the first yoke 6, and the other end 7b with a thicker outer diameter can be contacted with the plunger 5, and the end 7a with a smaller outer diameter is inserted into the plunger 5 along the insertion hole 6a. The core 7 has a rod shape and is made of a magnetic material and can slide on the same axis of the core 5 . The same poles face each other across the plunger 5, and the other pole is arranged in contact with the first yoke 6, forming a magnetic circuit between the plunger 5, core 7, and yoke 6, and attracting the plunger 5 and core 7. two permanent magnets 8 that generate magnetic force Φ in the direction of
A second yoke 9 made of a plate-shaped magnetic material and having a permanent magnet 8 arranged on its outer periphery to reduce magnetic resistance between the plunger 5 and the permanent magnet 8; A coil 11 that excites the magnetic circuit by applying a current is provided on the outer periphery of a pipe 10 made of a non-magnetic material, which is disposed in the center of which a plunger 5 and a core 7 can operate. The flange 2 made of a non-magnetic material urges the plunger 5 in a direction in which the valve body 4 approaches the valve seat 1, and includes a first spring 12 that is compressed and disposed between the valve body 4 and the plunger 5.

A spring receiver 13 disposed at the end 7C of the plunger 5 of the core 7 biases the core 7 in a direction away from the valve seat I, and is compressed and disposed between the first yoke 6 and the first
The second spring 14 has a stronger reaction force than the second spring 12. The pipe 10 includes a first O-ring packing 16 that provides a gas seal between the inner circumferential surface of the flange 2 and a 200th ring that provides a gas seal between the inner circumferential surface of the pipe 10 and the core 7 so that the core 7 can slide. It has a gasket I7 to prevent the gas flowing through the gas passage 3 from leaking to the outside.

A third yoke 18 is disposed inside the pipe 10 in contact with the first yoke 6 and is made of a magnetic material and has a cylindrical shape on which the core 7 can slide.
It is equipped with

The operation of the cutoff valve of the first embodiment will be explained below.

In the open valve holding state shown in the figure, where the shutoff valve is open,
The attraction force F created by the magnetic flux Φ due to the magnetomotive force of the permanent magnet 8 resists the reaction force f of the first spring 12 during plunging 5.
As a result, the valve body 4 is separated from the valve seat 1, and an open state in which gas can pass between the valve seat 1 and the valve body 4 is maintained. At this time, the core 7 is urged by the second spring 14 in a direction opposite to the reaction force f by a force fs in the opposite direction, which is larger than the reaction force f of the first spring 12, and the end 7b is held in contact with the yoke 6. has been done.

Next, at the moment of the valve closing operation, a current is applied to the coil 11 to generate a magnetic field in the opposite direction of the magnetic flux Φ, and as a result, the attractive force F decreases and becomes smaller than the reaction force f of the first spring 12. The plunge +5 loses its balance in maintaining the valve open and separates from the core 7, and moves until the valve body 4 comes into contact with the valve seat 1 and stops moving, resulting in the valve closed state shown in FIG. 2. At this time, the core 7 receives the reaction force f of the second spring 14.
3, it is biased in the opposite direction to the reaction force f of the first spring 12 and held stationary. And during the plunge 5
and the core 7 are separated by light as shown by l in the figure, the attraction force F by the permanent magnet 8 becomes approximately zero, and the valve element 4 is brought into contact with the valve seat 1 by the reaction force of the first spring 12. is maintained and the valve is kept closed. Further, the core 7 is urged and held by a reaction force r of the second spring 14 in a direction opposite to the reaction force f of the first spring 12.

When returning to the open state by opening the valve seat 1 and the valve body 4 and opening the shutoff valve, a large external load F in the opposite direction is applied to the core 7 by the reaction force f of the second spring 14, for example manually. is applied to the spring receiver 13, the core 7 moves and contacts the plunger 5, and the attraction force F created by the magnetic flux Φ due to the magnetomotive force of the permanent magnet 8 becomes larger than the reaction force f of the first spring 12 again, and the plunger 5 and The core 7 is attracted as shown in FIG.

After that, when the external load P is removed, the core 7 attracts the plunger 5 due to the reaction force f of the second spring 14, and the end 7b of the core 7 comes into contact with the yoke 6 and moves to the position where it stops moving, and the valve The body 4 is pulled away from the valve seat 1, a gap is created between the valve seat 1 and the valve body 4, and the valve returns to the open state through which gas can pass.

As described above, the cutoff valve of the first embodiment is in a state where the external load P is continuously applied to the spring receiver 13 due to, for example, a failure of the external load application mechanism (not shown) or a child's mischief. In this case, when the valve is in the closed state or the valve body 4 is in the middle of the valve-closing operation, applying current to the coil II closes the valve even in the latter case and maintains the closed state, thus realizing a forced valve-opening state. It is possible to have a fail-safe function to prevent a state in which an external load cannot be released due to an inoperable state and to prevent tampering.

A shutoff valve according to a second embodiment of the present invention is shown in FIG.

In FIG. 4, 20 is a pin protruding from the core 21,
A power transmission mechanism 24 that engages with a cam 23 formed on the return button 22 and operates the core 21 is configured.

25 is a second spring that biases the return button 22 in the return direction, and 26 is a frame. The rest of the configuration is the same as that in FIG. 1, and the explanation will be omitted.

The operation of the cutoff valve shown in FIG. 4 will be explained below. The operation of the valve body in each of the open holding state where the shutoff valve is open, the moment of the valve closing operation, and the valve closing holding state is basically the same as that in the first embodiment of the present invention, so a detailed explanation will be omitted. do. The second spring force f in the isolation valve of FIG. 1 is the axial component of the reaction force f of the second spring 25 transmitted by the cam 23 in the isolation valve of FIG. becomes.

To open the shutoff valve, press the return button 22 to move the return button 22, power is transmitted to the core 21 by the cam 23, the core 21 moves in the axial direction of the plunger 5, and the plunger 5 is moved. The attraction force F created by the magnetic flux Φ due to the magnetomotive force of the permanent magnet 8 is the first spring 12
becomes larger than the reaction force f, and the plunger 5 and the core 21 are attracted to each other. After the plunger 5 and the core 21 are attracted to each other, the pushing operation is stopped and the external force is released, and the second spring 25
Reaction force f, component force F. Accordingly, the core 21 is attached to the large diameter portion 21 of the core 21 with the plunger 5 adsorbed.
b moves to a position where it contacts the yoke 6 and stops its movement, and the valve body 4 is separated from the valve seat 1 to return to the valve open state.

As described above, by disposing the cam 23 in the shutoff valve of the second embodiment, there is no need to dispose a return device coaxially with the plunger 5, and for example, the return device can also be installed in a direction perpendicular to the central axis of the plunger 5. This has the effect of allowing a large degree of freedom in design.

A shutoff valve according to a third embodiment of the present invention is shown in FIG.

In FIG. 5, a female threaded portion 27a is formed in the first yoke 27, a threaded portion 28a is formed in a narrow diameter portion of the core 28, and is screwed into the female threaded portion 27a, and a male threaded portion 28a.
A gear 30 is joined to the end of the gear 30, and a geared motor (1i drive unit) 31 is connected to the gear 30.

Further, the mechanism corresponding to the second spring 14 in FIG. 1 is not present in the shutoff valve in FIG. 5, and the other configurations are the same as in FIG. 1, so a description thereof will be omitted.

The operation of the cutoff valve of the third embodiment will be explained below.

When the shutoff valve is open, the valve is held open, the moment the valve closes,
Since the valve closed holding state is basically the same as the shutoff valve shown in FIG. 1, the description thereof will be omitted. The second spring force r in the cutoff valve of FIG. 1 is equal to the force r of the second spring in the cutoff valve of FIG.
- The force is due to the stall torque of the geared motor 31 transmitted by the male threaded portion 28a and the gear 30. To open the shutoff valve, the geared motor 31 is electrically driven, and the rotation of the geared motor 31 is transmitted to the core 28 through the gear 30, and the male threaded portion 28a and the female threaded portion 27a rotate the core 28 in a straight line in the axial direction. The core 28 moves in the axial direction of the plunger and comes into contact with the plunger 5, and the attraction force F due to the magnetic flux Φ due to the magnetomotive force of the permanent magnet 8 becomes larger than the reaction force r of the first spring 12, and the plunger 5 and the core 28 is adsorbed. When the rotation of the geared motor 31 is reversed after the plunger 5 and the core 28 are attracted, the core 28 moves to the position where the large diameter portion 28b of the core 28 contacts the yoke 27 and stops moving while the plunger +5 is attracted. Then, the valve body 4 is separated from the valve seat 1 to return to the open state. After returning to the open state, the geared motor 31
The power supply will be cut off.

As described above, the cutoff valve according to the third embodiment of the present invention shown in FIG. The receiving section of the gas cutoff device that receives the signal operates the geared motor 31 to return the valve open. Furthermore, if a current is applied to the coil 10 regardless of the position of the core 28, the shutoff valve closes and shuts off or maintains the closed state. It has the effect of having a fail-safe function that allows the valve to close even when the valve is stopped.

Effects of the Invention As is clear from the above explanation, the shutoff valve of the present invention shuts off the gas passage even when the shutoff/return device of the external means is locked, thereby maintaining the safety and reliability of the gas shutoff device. It has an improving effect. In addition, it is possible to operate the electric drive unit by transmitting an electric signal from a remote location, and perform remote operations such as shutting off and releasing the cut off of the gas passage, making it easy to use.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing the shut-off valve according to the first embodiment of the present invention in an open state; FIG. 2 is a cross-sectional view showing the same valve in a closed state;
Figure 3 is a cross-sectional view showing the state in the middle of returning the valve open;
The figure is a cross-sectional view of a shut-off valve according to a second embodiment of the present invention, FIG. 5 is a cross-sectional view of main parts of a shut-off valve according to a third embodiment of the present invention, and FIGS. FIG. l...Valve seat, 3...Gas passage, 4...
... Valve body, 5, ... Plunger, 7.21.
28... Core, 8... Permanent magnet, 1
1... Coil, 12... First spring, 14.25... Second spring, 24
...Power transmission mechanism (external means), 31...
...Geared motor (electric drive unit). Name of agent: Patent attorney Shigetaka Awano Haka 1 person 1 - Issuke & 7° - Core 8-1 Kufu Kamishi Ll - File 21-' Fur slant, work barley' [The (J 劃) Tato Part Means J-No. Z Lisp 1 Nonku Fig. 3 17F Motor

Claims (2)

[Claims] (1) A magnetic forming means that forms magnetic circuits in opposite directions by energizing a permanent magnet and a coil, a plunger and a core that are housed in the magnetic forming means and slide on a common axis, and a core that protrudes from the magnetic forming means. A valve body is fixed to the end of the plunger, is biased via a first spring, and abuts against a valve seat facing the magnetic formation means to shut off the gas passage; A shut-off valve having a protruding core biased in a direction opposite to the plunger and external means for returning the core within the magnetic forming means. (2) The shutoff valve according to claim (1), comprising a core screw-fitted to the magnetic formation means, and an electric drive unit that rotates the core and moves the core coaxially with the plunger.