JPH076582B2 - Gas shutoff valve reset device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used in a gas meter having a built-in shutoff valve, and when an abnormality such as gas leakage or abnormal use of gas occurs, a current is passed through the shutoff valve to shut it off. After that, the present invention relates to a return mechanism for returning the shutoff valve.

2. Description of the Related Art Generally, as shown in FIG. 3, a gas meter return unit has a gas meter body 1 and a return shaft case 2 fitted with a screw portion 1a of the gas meter body 1. The return shaft 3 enters the return shaft case 2, and the return shaft cap 4 enters between the return shaft case 2 and the return shaft 3. The O-ring 5 for gas seal, the flat washer 6, and the return spring 7 are included in the return shaft case 2
And between the return shaft 3 as well. The E-shaped retaining ring 8 is the return shaft 3
Enter the groove 3a of the inner cylinder 9 and cover the inner cylinder 9, and the claw 9a of the inner cylinder 9
The inner cylinder 9 is fixed by entering the groove 3b of the return shaft 3. The U-shaped packing 10 enters the groove 1b of the gas meter body 1,
The gas meter body 1 and the inner cylinder 9 are sealed. 11 is a shut-off valve, and the structure has an electromagnetic coil 12, and this electromagnetic coil 12
The outer surface of the fixed yoke 13 is covered with a substantially U-shaped fixed yoke 13, a permanent magnet 14 is provided on the inner bottom portion of the fixed yoke 13, and a fixed iron core 15 is provided on the upper portion thereof. Auxiliary fixed yoke 16 is electromagnetic coil 12
The holding metal fitting 17 covers from above the auxiliary fixed yoke 16. A movable iron core 18 is inserted into a hole inside the electromagnetic coil 12, and a valve rubber 19 and a valve rubber receiver 20 are inserted and fixed to the inner cylinder 9 side. The shut-off spring 21 is assembled between the valve rubber receiver 20 and the holding metal fitting 17.

The cutoff valve 11 is normally held by the fixed iron core 15 and the movable iron core 18 against the force of the cutoff spring 21 by the attraction force of the permanent magnet 14, and the energization of the electromagnetic coil 12 causes the permanent magnet 14 to move.
The electromagnetic force is generated in the opposite direction to reduce the attractive force, and the repulsive force of the blocking spring 21 causes the fixed iron core 15 to the movable iron core 18 to move.
Move away.

Normally, the shutoff valve 11 is in a state in which the fixed iron core 15 and the movable iron core 18 are adsorbed, and the gas that has entered from the A portion flows to the B portion through the hole 9b of the inner cylinder 9. In the event of an abnormality such as a gas leak or abnormal use of gas, a current is made to flow from the controller to the electromagnetic coil 12 of the shutoff valve 11, the movable iron core 18 is separated from the fixed iron core 15 as shown in FIG. The valve seat portion 1c of the body 1 is closed. When the return shaft 3 is pushed to restore it, the inner cylinder 9 fixed to the return shaft 3 pushes the valve rubber 19 against the shutoff spring 21 to bring the movable iron core 18 into contact with the fixed iron core 15 and restore the shutoff valve 11. Adsorb.

Problems to be Solved by the Invention However, with the above configuration, the shutoff valve 11
Although no problem smaller differential pressure between the return side part B side A part, become large, the load f _p according to the valve rubber receiving 20 of the fixed iron core 15 and the suction force F a cutoff spring 21 between the movable iron core 18 If greater than the difference between the reaction force _{f s (f p> F-} f
_s ) Even when the return shaft 3 is pressed, the shutoff valve 11 does not return and adsorb.

The present invention solves the above-mentioned conventional drawbacks, and an object of the present invention is to provide a gas shut-off valve resetting device that can restore the valve opening without changing the specifications of the components of the magnetic circuit even if the allowable supply gas pressure is increased.

Means for Solving the Problems In order to solve the above problems, the present invention urges an opening end surface by pre-energizing an auxiliary spring between the tip of the return shaft protruding into the inner cylinder and the inner cylinder end closing surface. This is provided with an auxiliary inner cylinder in which the cylinder end closing surface is loosely fitted to the return shaft toward the outer side of the tip of the return shaft.

With the above configuration, when the return shaft is pushed toward the valve portion when the valve portion is in the valve closed state, the auxiliary inner cylinder first contacts the valve seat contact surface of the valve portion, and then the inner cylinder hits. Then, the force applied to the return shaft to both of them pushes the valve portion back to the open state against the gas pressure and the force of the shutoff spring. When the valve is opened, the adsorbing force by the permanent magnet is applied to the operating iron core in the valve opening direction, and when the force applied to the return shaft is relaxed, the auxiliary inner cylinder is pushed back with the inner cylinder abutting against the valve section. The gas on the primary side enters through the gap between the opening end and the valve portion, and the closing force of the valve portion due to the gas pressure applied to the valve portion is released. next,
Even if the pressing force of the return shaft is removed, the valve open state can be maintained by itself because the attraction force of the movable iron core by the permanent magnet is stronger than the valve closing force by the shutoff spring. When it is desired to reduce the gas passage resistance, the return shaft may be returned to the closed position by a restoring spring or the like.

In this way, even if there is a usage example in which the allowable supply gas pressure is higher than the standard value, the allowable supply gas pressure can be increased according to the biasing force of the auxiliary spring in advance, and the permanent magnet or electromagnetic The specifications of the parts of the magnetic circuit formed by the coil etc. do not need to be changed.

Embodiment One embodiment of the present invention will be described below with reference to the drawings. 1 and 2 are cross-sectional views of the return portion and the shutoff valve portion of the gas meter in the embodiment of the present invention. The same parts as those of the above-mentioned conventional example are designated by the same reference numerals, detailed description thereof will be omitted, and different parts will be mainly described.

FIG. 1 shows a state in which the valve rubber 19 is in contact with the valve seat portion 1c and the shutoff valve 11 is shut off. In FIG. 1, 9 is an inner cylinder whose dimension y ₀ is slightly longer than the conventional one, and 3 is a return shaft whose tip is extended. The inner cylinder 9 has an auxiliary spring 22 on its inner side.
Then, the auxiliary inner cylinder 23 is inserted into the return shaft 3 and fixed by the retaining ring 24. In this case, in the shutoff valve 11, the dimension x from the valve rubber 19 to the auxiliary inner cylinder 23 is smaller than the dimension y from the valve rubber 19 to the inner cylinder 9. When the return shaft 3 is pushed toward the shutoff valve 11, the auxiliary inner cylinder 23 first comes into contact with the valve rubber 19, and subsequently the auxiliary spring 22 has a smaller load than the shutoff spring 21, so that the auxiliary spring 22 has a dimension yx. Compress only minutes. Next, inner cylinder 9
Hits the valve rubber 19 and pushes the valve rubber 19 between the inner cylinder 9 and the auxiliary inner cylinder 23 to bring the movable iron core 18 into contact with the fixed iron core 15 to adsorb the shutoff valve.

FIG. 2 shows a state in which the shutoff valve 11 is adsorbed. The movable iron core 18 is pulled to the right by the attraction force F of the permanent magnet 14, and the valve rubber receiver 20 has a stroke 1 after the valve is closed and a preload stroke when the valve is closed.
The sum of l ₀ is multiplied by the spring constant k ₁ of the breaking spring 21 (l +
It is pushed to the left with l ₀ ) k ₁ = fs. When the inner cylinder 9 and the valve rubber 19 are in contact with each other, the force PS due to the gas pressure P (kg / cm ² ) applied to almost the entire area S (cm ² ) of the valve rubber receiver 20 is applied to the valve rubber 19.
= _{F p} acts on the left.

In other words, when the return shaft 3 is pushed to the right until it stops, a force greater than the leftward force calculated by fs + fp−F = (l + l ₀ ) k ₁ + PS−F is pressed to the right side of the return shaft 3 against the valve rubber 19. It is added as a force. When (l + l ₀ ) k ₁ + PS-F <0 is set, when the pushing force of the return shaft 3 is relaxed and the return spring 7 causes the return shaft 3 to return to the left side to a position just smaller than y−x. The force fr by which the auxiliary inner cylinder 23 pushes the valve rubber 19 is fr≈m ₁ k ₂ (where m is the compression allowance 3 when the auxiliary spring 22 is set, and k ₂ is the spring constant). At this time,
fr = fs + fp-F.

By modifying this equation, fp = F-fs + fr- (1).

Next, when the conventional auxiliary inner cylinder 23 is not provided, the gas pressure that allows self-holding is provided even if the pressing force of the return shaft 3 is relaxed from the valve open state.
If P ₀ , then fs + fp ₀ −F = 0 and is transformed to fp ₀ = F−Fs− (2).

Then, by subtracting the equation (2) from the equation (1), Δfp = fp−fp ₀ = (p−p ₀ ) S = fr≈m ₁ k ₂ is obtained, and this equation is modified to obtain ΔP = P−P _{0 = m 1 k 2 / S} - obtaining (3).

From this, by pre-compressing the auxiliary spring 22 by the length m _1, and having the auxiliary inner cylinder 23, the magnetic circuit of the shut-off valve 11 remains the conventional design specifications, and the allowable value P of the gas supply pressure is P.
Can be increased according to the set load m ₁ k ₂ of the auxiliary spring 22, as shown in the equation (3).

EFFECTS OF THE INVENTION As described above, when the gas supply pressure is higher than the permissible standard gas pressure, the gas shutoff recovery device of the present invention does not change the specifications of the magnetic circuit composed of permanent magnets, electromagnetic coils, etc. By providing the auxiliary inner cylinder, which is loosely fitted to the return shaft via the inner cylinder, it is possible to enable the shutoff return operation of the gas passage.

[Brief description of drawings]

FIG. 1 is a sectional view of a return portion when a shutoff valve is shut off in one embodiment of the present invention, FIG. 2 is a sectional view of a return portion when the shutoff valve is back-adsorbed, and FIG. 3 is a conventional example. FIG. 4 is a cross-sectional view of the return portion when the shut-off valve is adsorbed, and FIG. 4 is a cross-sectional view of the return portion when the shut-off valve shuts off. 3 ... Return shaft, 9 ... Inner cylinder, 11 ... Shut-off valve, 21 ... Shut-off spring, 22 ... Auxiliary spring, 23 ... Auxiliary inner cylinder.

Claims (1)

[Claims] Claim: What is claimed is: 1. The attraction force of a permanent magnet to a movable iron core is used as a self-holding force in a valve open state, and the attraction force of an electromagnetic coil to a movable iron core weakens the attraction force to provide a valve closing starting force. The valve portion that is fixed to the movable iron core protruding toward the primary side of the passage and the biasing force that pushes the valve portion against the valve seat portion of the gas passage are closed by the combined force of the pressing force due to the primary gas pressure. A shutoff spring for self-holding force in the valve state, a return shaft penetrating the secondary side wall surface of the gas passage and sliding in an airtight manner, and the valve portion for opening the valve portion against the self-holding force in the valve closed state. An inner cylinder having an opening cylinder end for pushing back to a valve state, the cylinder part sliding airtightly on the inner diameter wall surface of the valve seat part, and a cylinder end closing surface having a gas passage hole fixed in the middle of the return shaft; , An auxiliary screw is provided between the tip of the return shaft protruding inside the inner cylinder and the cylinder end closing surface. An auxiliary inner cylinder, which is biased in advance by a ring and has an opening cylinder end directed toward the outside of the tip of the return shaft and a cylinder end closing surface of which is loosely fitted to the return shaft, is provided. A return device for a gas cutoff valve, wherein a gap between the opening of the auxiliary inner cylinder and the end of the opening of the inner cylinder from the valve seat contact plane is set to be larger.