JPH084925A - Safety valve - Google Patents

Abstract

PURPOSE:To provide a safety valve capable of surely shutting off the gas supply when the thermally expanding fluid is leaked. CONSTITUTION:The safety valve is provided with a body 1 having a valve seat 1d in the middle of a gas flow passage 1c, a valve member 6 energized to the direction of the valve seat by a first spring member 8, a magnetic member which is continuously arranged on the valve member 6, a bellows 10 which is arranged opposite to the magnetic member 5, a working rod 11 to be abutted on the magnetic member 5 by the elongation of the bellows 10, a magnet 9 to be movably fitted to the working rod 11, a stopper member 7 to regulate the movement of the magnet in the direction of the magnetic member, and a temperature sensing body 13 to detect the temperature which is communicated with the bellows 10 and in which the thermally expanding fluid is sealed. When the temperature sensing body 13, etc., is damaged and the thermally expanding fluid is leaked, the magnet 9 is detached from the magnetic member 5 by making use of the elongation of the bellows 10 to release the attraction between the two, and the valve member 6 is pressed against the valve seat 1d under the energization of the first spring member 8 to shut off the gas supply.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a safety valve which automatically shuts off gas supply when the temperature at a temperature detecting point rises abnormally.

[0002]

2. Description of the Related Art Japanese Utility Model Publication No. 3-115277 discloses a safety valve of this type.

This safety valve has an inlet 2 as shown in FIG.
The valve seat 2 is provided in the middle of the internal flow path 21c connecting the 1a and the outlet 21b.
A main body 21 having 1d, a valve 22 arranged to be movable back and forth with respect to a valve seat 21d, and a reversing plate 23 for pressing or separating the valve 22 from the valve seat 21d by an urging force by a reversing action.
A working chamber 24 capable of pressing the valve 22 toward the valve seat by deformation due to an increase in internal pressure; a thermosensitive body 25 for temperature measurement, which is in communication with the working chamber 24 and contains a thermal expansion fluid therein; The reset button 26 can be pressed in a direction away from the seat 21d.

The above-mentioned safety valve is used by placing the main body 21 in the middle of the gas pipe leading to the gas equipment and arranging the heat sensitive body 25 at the temperature measuring location. When the temperature at the temperature detection point rises and reaches a predetermined abnormally high temperature range, the internal pressure of the working chamber 24 increases due to the expansion of the thermal expansion fluid in the heat sensitive body 25, and the upper surface of the working chamber 24 is deformed upward and the valve 22 is pressed upward, whereby the reversing plate 23 is reversed upward, the valve 22 is pressed against the valve seat 21d, and the gas supply is shut off. Since the closing of the valve 22 is held by the urging force of the reversing plate 23, the valve 22 should be opened unless the reset button 26 is pressed even if the temperature of the temperature sensing point drops and the deformation of the working chamber 24 returns. Without gas shut off state is maintained.

[0005]

In this type of safety valve using a thermal expansion fluid, the thermal expansion element 25 is damaged due to damage to the heat sensitive element 25 or the conduit connecting the heat sensitive element 25 and the working chamber 24, and the leakage of the thermal expansion fluid occurs. Then, even if the temperature at the temperature detection point rises and reaches the abnormally high temperature range, there is a problem that the valve 22 is not closed as described above and the gas supply is continued as it is.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a safety valve capable of reliably shutting off gas supply when a leak of a thermal expansion fluid occurs.

[0007]

In order to achieve the above object, the invention of claim 1 is such that a main body having a valve seat in the middle of a gas flow path connecting an inlet and an outlet, and a spring member urges the valve seat toward the valve seat. Valve member, a magnetic member connected to the valve member, a telescopic member arranged to face the magnetic member, an operating rod that can come into contact with the magnetic member by the expansion of the telescopic member, and a movable rod that is movably fitted to the operating rod. A magnet mounted thereon, a stopper member for restricting movement of the magnet in the direction of the magnetic member, and a heat-sensing body for temperature measurement in which a thermal expansion fluid is sealed inside and in communication with the expansion / contraction member. The feature is that the valve opened state is maintained by force and the valve can be closed by releasing the adsorption.

According to a second aspect of the present invention, in the safety valve according to the first aspect, a shaft is connected to the valve member, and one end of the shaft is projected to the outside of the main body.

According to a third aspect of the present invention, in the safety valve according to the first or second aspect, the second aspect of urging the elastic member in the contracting direction is also preferable.
It is characterized by the provision of the spring material.

[0010]

According to the invention of claim 1, when the temperature of the temperature measuring portion rises to reach a predetermined abnormal high temperature range with the valve opened, the expansion member expands due to expansion of the thermal expansion fluid and the tip of the operating rod becomes a magnetic member. Abut and press this. Since the movement of the magnet is regulated by the stopper member, the magnetic member is separated from the magnet by the above pressing and the mutual attraction is released, and the valve member is pressed against the valve seat by the urging force of the spring material to cut off the gas supply. To be done.
Also, when the thermal expansion fluid leaks due to damage to the heat-sensitive body in the valve open state, the expansion member contracts due to the decrease in internal pressure, and the operating rod separates from the magnetic member together with the magnet. The adsorption between the valve member and the valve member is released, and the valve member is pressed against the valve seat by the urging force of the spring member to cut off the gas supply.

According to the second aspect of the present invention, the valve member in the closed state is separated from the valve seat by moving the shaft by an external operation, the attraction between the magnetic member and the magnet is restored, and the valve member is opened again. It can be in a state. Other functions are similar to those of the invention of claim 1.

According to the third aspect of the present invention, the contraction of the expansion / contraction member when the leakage of the thermal expansion fluid occurs can be promptly performed by utilizing the urging force of the second spring member. Other functions are similar to those of the invention of claim 1 or 2.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a vertical sectional view of a safety valve according to the present invention in a valve open state. In the figure, 1 is a main body, 2 is a shaft, 3 is a reset button, 4 is a seal member, 5 is a magnetic member, 6 is a valve member, 7 is a stopper member, 8 is a first spring member, 9 is a magnet, and 10 is Bellows, 11 is an operating rod, 12
Is a second spring member, 13 is a heat sensitive body, and 14 is a capillary.

The main body 1 has an inlet 1a and an outlet 1b opposed to each other on its side surface, and has a gas flow passage 1c therein which connects the inlet 1a and the outlet 1b. Further, a circular valve seat 1d opening in the vertical direction is provided in the middle of the gas flow passage 1c, and holes 1e and 1f are formed in the center of the upper wall and the center of the lower wall of the valve seat 1d.
Are formed through each. Further, a cylindrical portion 1g with an internal screw is formed in the lower portion of the main body 1, and an adjusting cylinder 1h with an external screw is screwed into the cylindrical portion 1g to define a mechanism chamber 1i therebetween. .

The shaft 2 has a flange 2a at a substantially middle portion thereof, and an upper portion thereof is slidably inserted into an upper hole 1e and an upper end thereof is projected to the outside of the main body. A reset button 3 is attached to the upper end of the shaft 2.

The seal member 4 is formed of a rubber material such as NBR into a cylindrical shape, and its upper end is fixed to the upper wall of the gas passage 1c, and its lower end small diameter portion is in close contact with the flange 2a of the shaft 2. The seal member 4 prevents the gas from leaking to the outside from the gas passage 1c through the upper hole 1e.

The magnetic member 5 is made of a magnetic material such as stainless steel or steel and is formed in a disk shape. The lower end of the shaft 2 is fitted in the upper surface hole 5a. At the center of the lower surface of the magnetic member 5, a recess 5b for receiving the upper end of an operating rod described later is provided.

The valve member 6 is formed of a rubber material such as NBR into a disc shape and is fixed to the upper surface of the magnetic member 5 so that the upper surface faces the valve seat 1d. This valve member 6 has an annular piece 6 around it.
a is integrally formed, and the peripheral edge of the annular piece 6a is fixed to the inner wall of the main body 1 to enable vertical movement while deforming the inner wall. The valve member 6 also prevents gas from leaking from the gas flow passage 1c to the mechanism chamber 1i and the outside through the lower hole 1f.

The stopper member 7 has its upper end flange fixed to the inner wall of the main body 1 and has a step 7a on its inner surface against which the lower surface of the magnetic member 5 abuts. The lower end of the stopper member 7 and the lower end of the magnetic member 5 that is in contact with the stopper member 7 are at the same height position and are in contact with and attracted to the upper surface of a magnet 9 described later.

The first spring member 8 is composed of a coil spring or the like, and is stretched between the lower surface of the magnetic member 5 and the lower end flange of the stopper member 7. The first spring 8 serves to urge the valve member 6 toward the valve seat.

The magnet 9 is in the form of a disk having a hole 9a in the center, and is slidably fitted to a rod-shaped portion of an operating rod 11 which will be described later. This magnet 9 is moved upwardly by the stopper member 7.
Is regulated at the lower end of the valve, and serves to hold the valve member 6 in an open state by attracting the magnetic member 5 at the same position.

The bellows 10 is made up of an expandable container whose peripheral surface is formed in a bellows shape, and is arranged in the mechanism chamber 1 via a support member 10a.

The operating rod 11 has its lower end fixed to the upper end of the bellows, and its rod-shaped portion is slidably inserted into the lower hole 1f. The operating rod 11 has an engaging flange 11a integrally or separately at the upper end thereof, and the engaging flange 11a is engaged with the upper side of the hole of the magnet 9 and is located in the lower surface recess 5b of the magnetic member 5. There is.

The second spring member 12 is composed of a coil spring or the like, and is stretched between the upper surface of the mechanism chamber 1i and the operating rod 11. The second spring material 12 serves to urge the bellows 10 in the contraction direction.

The temperature sensitive body 13 is composed of a cylindrical container and has a mounting flange 13a and a sealing pipe 13b. A thermal expansion medium, for example, an alcohol-based volatile liquid that starts expanding at a predetermined temperature is enclosed in the heat sensitive body 13. Further, the heat sensitive body 13 and the bellows 10 are connected via a capillary (small-diameter pipe material) 14, and pressure change due to expansion and contraction of the thermal expansion medium is caused by the capillary 14.
Is transmitted to the bellows 10 through.

The above-mentioned safety valve is used by inserting the main body 1 in the middle of the gas pipe leading to the gas equipment, and attaching the heat sensitive body 13 to the temperature measurement location, for example, the inner and outer wall surfaces of the oil tank when the gas equipment is a fryer. It

During normal gas supply, as shown in FIG.
The magnetic member 5 is attracted to the magnet 9 against the biasing force of the first spring member 8, and the valve member 6 is separated from the valve seat 1d. In this valve open state, the gas flowing into the inlet 1a of the main body 1 flows out from the outlet 1b through the gas flow passage 1c.

When the temperature at the temperature measuring point rises to reach a predetermined abnormal high temperature region in the valve open state of FIG. 1, as shown in FIG.
The expansion of the thermal expansion fluid in the heat sensitive body 13 causes the bellows 10 to expand.
The internal pressure rises and the bellows 10 expands against the biasing force of the second spring member 12. Then, as the bellows 10 expands, the operating rod 11 rises, and the upper end of the operating rod 11 reaches the magnetic member 5.
Abut and push it up. Since the upward movement of the magnet 9 is regulated by the stopper member 7, the magnetic member 5 is separated from the magnet 9 and the mutual attraction is released in the above-mentioned pushing up, and the valve member 6 is actuated by the urging force of the first spring member 8. The gas supply is cut off by pressing against the seat 1d. Along with this, the shaft 2 rises and the reset button 3 separates from the main body 1.

In the state shown in FIG. 2, when the temperature at the temperature measuring point falls and reaches a predetermined safety zone, the thermal expansion fluid in the heat sensitive body 13 contracts and the internal pressure of the bellows 10 drops, so that the bellows 10 moves to the second position. It contracts while receiving the biasing force of the spring member 12, and the operating rod 11 descends as the bellows 10 contracts. However, even if the operating rod 11 descends, the magnetic member 5 and the valve member 6
Holds the valve closed position by the urging force of the first spring member 8, the state of FIG. 1 will not be restored unless the reset button 3 is pushed down by an external operation, and the temperature of the temperature measurement point eventually drops. Only by doing so, the valve member 6 is not opened and the gas cutoff state is maintained.

When the thermosensitive element 13 and the capillary 14 are damaged when the valve is open as shown in FIG. 1 and the thermal expansion fluid leaks due to the damage, as shown in FIG. Contracts while receiving the biasing force of the second spring member 12. Then, as the bellows 10 contracts, the operating rod 11 descends, and along with this, the magnet 9 also moves toward the upper end flange 1.
It descends while being engaged at 1a. As a result, the magnet 9 is separated from the magnetic member 5 and the stopper member 7, and the magnetic member 5
The attraction between the magnet 9 and the magnet 9 is released, the valve member 6 is pressed against the valve seat 1d by the urging force of the first spring member 8, and the gas supply is cut off. Along with this, the shaft 2 rises and the reset button 3 separates from the main body 1. Incidentally, after the leakage of the thermal expansion medium is repaired, the state shown in FIG. 1 can be restored by pushing down the reset button 3 by an external operation.

As described above, in the safety valve of the present embodiment, when the temperature at the temperature detection point rises and reaches the abnormally high temperature range, the valve member 6 in the open state can be closed to cut off the gas supply, and of course, the heat sensitive body. Also when the thermal expansion fluid leaks due to damage to the nozzle 13, the capillary 14, etc., the valve member 6 is closed to interrupt the gas supply, and inadvertent gas supply is reliably prevented to ensure high safety. can do.

When the leakage of the thermal expansion fluid occurs, the bellows 10 can be shortened by utilizing the urging force of the second spring member 12, so that the valve can be quickly closed to instantaneously supply the gas. Can be shut off.

Furthermore, since the attraction force of the magnet 9 is used to maintain the valve open state, the force relationship between the urging force of the first spring member 5 and the attraction force of the magnet 9 can be set easily and appropriately, and No malfunction occurs even with repeated use.

The spring material in the embodiment may be another spring material such as a leaf spring, and the bellows may be appropriately substituted as long as it can expand and contract due to a change in internal pressure. Further, the heat-sensitive body may have another shape, for example, a vertically long rod-shaped container, and its mounting position may be variously changed according to the gas equipment to be used.

[0035]

As described above in detail, according to the first and second aspects of the present invention, when the heat-sensitive body or the like is damaged and the thermal expansion fluid leaks, the valve member in the open state is closed. Thus, the gas supply can be cut off, the careless gas supply can be reliably prevented, and high safety can be ensured. Moreover, since the magnet's attractive force is used to maintain the valve open state, the force relationship between the spring material's urging force and the magnet's attractive force can be set easily and appropriately, and malfunctions can occur even with repeated use. There is no.

According to the invention of claim 3, when the leakage of the thermal expansion fluid occurs, the elastic member is contracted by utilizing the urging force of the second spring member, thereby promptly closing the valve. The gas supply can be cut off instantly. Other effects are similar to the above.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of a safety valve according to the present invention in a valve open state.

FIG. 2 is a diagram showing an operation when a detected temperature reaches an abnormally high temperature range.

FIG. 3 is a diagram showing an operation when a thermal expansion fluid leaks.

FIG. 4 is a vertical sectional view of a safety valve showing a conventional example.

[Explanation of symbols]

1 ... Main body, 1a ... Inlet, 1b ... Outlet, 1c ... Gas flow path,
1d ... valve seat, 2 ... shaft, 5 ... magnetic member, 6 ... valve member, 7 ... stopper member, 8 ... first spring material, 9 ... magnet, 1
0 ... Bellows, 11 ... Actuating rod, 12 ... Second spring member, 1
3-Sensor.

Claims (3)

[Claims] 1. A main body having a valve seat in the middle of a gas flow path connecting an inlet and an outlet, a valve member biased in a valve seat direction by a spring member, a magnetic member connected to the valve member, and a magnetic member. An elastic member disposed opposite to each other, an operating rod that can come into contact with the magnetic member by expansion of the elastic member, a magnet movably fitted to the operating rod, and a stopper member that restricts movement of the magnet in the magnetic member direction. It is equipped with a thermosensitive body for temperature measurement, which communicates with the expansion and contraction member and contains a thermal expansion fluid inside, and holds the valve open state by the attraction force between the magnetic member and the magnet, and can close the valve by releasing the attraction. The safety valve characterized in that 2. The safety valve according to claim 1, wherein a shaft is connected to the valve member and one end of the shaft is projected to the outside of the main body. 3. The safety valve according to claim 1, further comprising a second spring member for urging the expansion / contraction member in the contracting direction.