JPH03616Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention relates to an improvement of a gas cutoff valve that cuts off the flow of gas in a pipe when an abnormal situation such as a gas leak occurs.

(Prior Art) Although not specifically shown, a conventional gas cutoff valve of this type consists of a valve body and an electromagnetic mechanism.
It has a valve seat and a valve body that opens and closes the valve seat, defines a gas flow passage inside through the valve seat, and has a configuration in which the valve body is biased in the closing direction of the valve seat by a spring. ing.

Further, the electromagnetic mechanism has a plunger having the valve body connected to its lower end, and an electromagnetic section consisting of an electromagnetic coil, a permanent magnet, etc. located concentrically outside the plunger.

In actual operation, the plunger is raised and attracted to a high position by the magnetic field lines generated by energizing the electromagnetic coil of the electromagnetic part, and then the plunger is maintained at a high position by the magnetic force of the permanent magnet, and the valve body resists the spring. By moving the valve away from the valve seat, gas flow is allowed under normal conditions. Conversely, when an abnormal situation such as a gas leak occurs, an external sensing means that detects the occurrence of the abnormal situation and the sensing means are activated. A current is passed through the electromagnetic coil of the electromagnetic part via the connected control device, generating lines of magnetic force in the opposite direction to the magnetic force of the permanent magnet, and releasing the attracted state of the plunger, which in turn causes the spring to This action causes the valve body to descend, closing the valve seat and immediately cutting off gas flow.

Conventionally, as a means for transmitting signals of the open/closed state of the valve body to a control device, etc., an L-shaped arm member with a magnetic body attached to the tip is fixed to the side of the valve body, and an L-shaped arm member is attached above the arm member. A reed switch is installed separately, and the arm member is linked with the lift of the valve body to move the magnetic body toward and away from the reed switch, thereby detecting the open and closed states of the valve seat. A structure is adopted that transmits the detection signal to the control device.

(Problem to be solved by the invention) However, the conventional open/close detection structure requires an L-shaped arm member to attach the magnet body in addition to the reed switch/magnetic body for detecting open/close, so the number of parts is naturally reduced. Not only does this increase, but because the arm member comes into direct contact with the fluid, the arm member must be made of a corrosion-resistant material, and
It is necessary to provide a certain amount of clearance between the valve body and the arm member for fluid sealing, and if a foreign object or the like gets caught in this clearance, there is a risk that the reed switch will no longer generate a normal operating signal. Furthermore, since a dedicated space for raising and lowering the arm member inside the shutoff valve and a dedicated space for installing the reed switch are separately required, the shutoff valve itself becomes unnecessarily large.

Further, although reliable detection of the open/closed state by a reed switch is required, conventional open/close detection structures often suffer from false detections and lack reliability.

(Means for Solving the Problems) Therefore, the present invention was developed to effectively solve the problems of the keep solenoid structure of the conventional gas cutoff valve described above. The valve body has a valve seat and a valve body that opens and closes the valve seat, and the electromagnetic mechanism has a plunger connected to the valve body, and an electromagnetic part disposed concentrically outside the plunger. In the gas cutoff valve, a reed switch for opening/closing detection is disposed on the top surface of the electromagnetic part, and a manual operation shaft is connected to the upper end of the plunger, and a magnet body is fixed to the manual operation shaft to control the plunger. A configuration was adopted in which the reed switch is turned on and off by the approach and separation of the magnetic body from the reed switch as the magnet moves up and down.

(Function) Accordingly, in the present invention, by utilizing the upper surface of the electromagnetic part where a gap is inevitably defined in relation to the frame of the electromagnetic mechanism, a lead for opening/closing detection is attached to the upper surface of the electromagnetic part. While the reed switch is installed, a magnetic body is also installed on the manual operation shaft connected to the upper end of the plunger, so the reed switch and magnetic body can be installed without using the dedicated space and arm member required in the past. This not only greatly contributes to the miniaturization of the gas cutoff valve itself, but also enables reliable detection of the open/closed state.

(Example) Hereinafter, the present invention will be described in detail based on an example illustrating the gas cutoff valve according to the example.
As shown in Figure 2, the valve body 1A and the electromagnetic mechanism 1
The valve body 1A consists of a valve seat 2 and a valve seat 2.
It has a valve body 3 that opens and closes, and has a structure in which a gas inlet and outlet passage is defined through a valve seat 2.

Further, the electromagnetic mechanism 1B includes a plunger 5 that connects the valve body 3 to the lower end via a connecting member 4, and a solenoid 6a, a solenoid frame stopper 6b, a permanent magnet 6c, an iron plate 6d, and a solenoid 6a, a solenoid frame stopper 6b, a permanent magnet 6c, an iron plate 6d, etc. The electromagnetic section 6 includes a frame 6e and the like. A spring 8 is installed between the flange 7 fixed to the lower part of the plunger 5 and the electromagnetic part 6, and the spring pressure of the spring 8 urges the valve body 3 in the closing direction of the valve seat 2.

Further, a reed switch 9 for opening/closing detection is disposed on the upper surface of the frame 6e of the electromagnetic part 6 that defines a gap with the frame 1b of the electromagnetic mechanism 1B, and a ring 10a is provided at the upper end of the plunger 5. A manual operation shaft 10 is integrally arranged, and a magnet body 11 is colored with fluorescent paint, red paint, etc. on the manual operation shaft 10.
is fixedly installed, and the reed switch 9 is turned on/off or off/on by the colored magnet body 11 approaching and separating from the reed switch 9 as the plunger 5 moves up and down, and the electromagnetic mechanism 1
As particularly shown in FIG. 3, a transparent cap 13 connected by a chain 12 is removably attached to the upper part of the frame 1b of B, and the upper end of the manual operation shaft 10 is housed in the cap 13. In an emergency during a power outage,
By removing the cap 13 and manually raising and lowering the operating shaft 10 via the ring 10a,
The valve seat 2 of the valve body 1A can be opened and closed without relying on the electromagnetic part 6, and the colored magnet body 11 can be easily seen through the transparent cover 13.

In this embodiment, a diaphragm 15 is attached to the connecting portions 14a and 14b of the valve body 1A and the electromagnetic mechanism 1B and to the lower end of the plunger 5 in order to seal between the valve body 1A and the electromagnetic mechanism 1B. At the same time, the flange 1 provided on the upper part of the valve body 1B
A bellows 17 is attached to the lower end of the plunger 5 and the bellows 17 doubly, and the bellows 17 and the diaphragm 15
A sealing structure is obtained by double mounting. still,
Needless to say, a gasket 18 such as an O-ring is separately attached to the connecting portion between the flange 16 and the electromagnetic mechanism 1B.

In addition, when the diaphragm 15 and bellows 17 are attached to the lower end of the plunger 5, both
By drilling through holes 15a and 17a in 5 and 17, inserting the connecting member 4 into each of the through holes 15a and 17a, and screwing the connecting member 4 onto the plunger 5, both 15 and 17 can be connected. Although it is to be installed twice, if both 15 and 17 are directly polymerized and screwed together,
Since each of the through holes 15a and 17a may deform and expand in diameter and the sealing performance may be impaired, a spacer 19 having an annular groove 19a is interposed between each of the through holes 15a and 17a, as shown in FIG. By making the hole edges of the diaphragm 15 and bellows 17 bite into each other, the diameter of the through holes 15a and 17a is prevented from expanding.

Further, a detection path 20 extending to the corresponding wall of the electromagnetic mechanism 1B is formed on the secondary side of the valve body 1A, and a separate pressure sensor 21 is arranged at the end of the detection path 20. The pressure sensor 21 is configured to detect a decrease in gas pressure on the secondary side.

Therefore, in the normal state of the gas cutoff valve configured as described above, as shown in FIG. Valve seat 2 against 8
This allows the gas to flow through.

In this normal state, when an abnormal situation such as a gas leak occurs, the electromagnetic coil of the electromagnetic section 6 6a
An electric current is applied to generate lines of magnetic force in the opposite direction to the magnetic force of the permanent magnet 6c, so that the attraction of the plunger 5 is released and the valve body 3 is lowered together with the plunger 5 by the action of the spring 8. Then, as shown in FIG. 2, the valve seat 2 is closed, so that the gas flow is immediately cut off.

Moreover, in the process of shutting off the gas, as the plunger 5 descends, the colored magnet 11 on the manual operation shaft 10 connected to the plunger 5
approaches the reed switch 9 provided on the frame 6e of the electromagnetic part 6 and turns on or off the reed switch 9, so the control device closes the valve seat 2 by the switch on (or off) signal. It is possible to detect that the condition has been reached.

Next, when the abnormal situation is solved and repaired and the gas flow is restarted, current is applied to the electromagnetic coil 6a of the electromagnetic section 6 by the operation of the control device, so that the plunger 5 is moved by the generated magnetic field lines to the spring 8. It overcomes the pressure and rises to attract the solenoid frame stopper 6b, and after being attracted, the open state shown in FIG. 1 is ensured by the magnetic force of the permanent magnet 6c.

In this case, as the plunger 5 rises, the manual operation shaft 10 connected to the plunger 5
The upper magnet body 11 is separated from the reed switch 9 provided on the frame body 6e of the electromagnetic part 6,
This time, since the reed switch 9 is turned from on to off (or from off to on), the control device can detect that the valve seat 2 is in the open state based on the switch off (or on) signal.

(Effects of the invention) As described above, the present invention provides a reed switch for detecting opening/closing on the top surface of the electromagnetic part, a manual operation shaft connected to the upper end of the plunger, and a magnet body attached to the manual operation shaft. Since the reed switch is fixedly installed and the reed switch is turned on and off by approaching and separating the magnetic body from the reed switch as the plunger moves up and down, it does not require a dedicated space or an arm member as in the past. Since the reed switch and the magnet body can be easily installed, it not only greatly contributes to the miniaturization of the gas cutoff valve itself, but also enables reliable detection of the open/closed state.

Furthermore, the sensitivity of the reed switch does not need to be strictly defined by appropriately selecting the magnetic properties of the magnetic body, and there is no need to strictly define the mounting position of the reed switch. There is no need to strictly define
Selection is also extremely easy.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing the open state of the gas cutoff valve according to the embodiment of the present invention, Fig. 2 is a sectional view showing the same closed state, and Fig. 3 is a perspective view of the main part showing the relationship between the manual operation shaft and the cap. FIG. 4 is an enlarged cross-sectional view of a main part showing a state in which the diaphragm and bellows are attached. 1A...valve body, 1B...electromagnetic mechanism, 2...valve seat, 3...valve body, 5...plunger, 6...electromagnetic section, 9...reed switch, 10...manual operation shaft, 11... Magnetic body.

Claims (1)

[Scope of utility model registration request] Consisting of a valve body and an electromagnetic mechanism, the valve body has a valve seat and a valve body that opens and closes the valve seat, and the electromagnetic mechanism has a plunger that connects the valve body and is arranged concentrically outside the plunger. In the gas cutoff valve having an electromagnetic part, a reed switch for opening/closing detection is disposed on the upper surface of the electromagnetic part, a manual operation shaft is connected to the upper end of the plunger, and a magnet body is attached to the manual operation shaft. It is fixedly installed to prevent the magnetic body from approaching the reed switch as the plunger moves up and down.
A gas cutoff valve characterized in that a reed switch is turned on and off by separation.