JP2005140189A - Runoff preventing valve for liquefied gas - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To disclose a runoff preventing valve of liquefied petroleum gas using a float easy to adjust the buoyancy force accurately. <P>SOLUTION: The runoff preventing valve comprises a nozzle for supplying liquefied gas in a container main body to the downstream side, a valve seat and a valve element provided so that they can seat from the downside of this nozzle, a spring biasing the valve seat and valve element in the nozzle direction, and a float which pushes up the valve seat and valve element to the nozzle direction with the buoyancy via a valve shaft extending from the valve element. The float comprises a cylindrical float main body whose bottom surface is opened, and a lid body which covers the upper surface of this float main body, and the lid body is at least partially comprised of a magnetic body. A permanent magnet for magnetically attracting the magnetic body is provided in a position where the valve seat seats on the nozzle. The sum of the elastic force of the spring and the attraction force is set to be stronger than the gravity of the valve element and valve seat. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an outflow prevention valve for liquefied gas that functions reliably.

  There exists a thing disclosed by patent document 1 regarding this kind and the outflow prevention valve for liquefied gas.

JP-A-9-105500

  A device that supplies liquefied gas (liquid) from a container such as a cylinder to the evaporator and generates gas is provided with a valve that prevents the liquid from flowing out of the liquefied gas in the evaporator to avoid danger due to excessive supply. . By the way, many of the valves conventionally used are closed when the liquid level of the liquefied gas in the evaporator rises, but when the liquid level drops after that, the valve body automatically drops and opens. It is a structure to valve.

  When such an outflow prevention valve is incorporated in the evaporator of the liquefied gas, once the valve is closed, the gas supply to the consumer is shut off, and the burning fire may be extinguished at the burner tip. . However, with the above-described conventional structure, the gas is automatically supplied after the fire has extinguished, which is extremely dangerous when the downstream side is in a valve open state.

  The solution of this is the applicant's invention disclosed as the prior art. In the present invention, when the supply of gas is once interrupted due to the rise of the liquid level in the evaporator, the valve closed state can be maintained until reset is performed.

  By the way, in the above prior art of the applicant, the float moves up and down in the float cover as the liquid level rises and falls, and when the liquid level becomes higher, the valve seat provided on the upper side of the float is seated on the valve seat and the magnet To maintain the seated state. As the float material, a solid float made of synthetic resin such as NBR, for example, is laminated with a multi-stage coupling shaft. In general, this float functioned very effectively in the usual usage. However, when the pressure inside the cylinder is high, the volume of the resin float is compressed by the hydraulic pressure, leaving a problem that a predetermined buoyancy cannot be obtained. In addition, when the hydraulic pressure is very high, there is a problem that the float is crushed. On the other hand, since the float is made of resin, there is a problem that it is relatively weak in high temperature conditions.

  In the present invention, in order to achieve the above-described object, a nozzle that supplies the liquefied gas in the container body to the downstream side, a valve seat and a valve body that can be seated from below the nozzle, and the valve seat and A liquefied gas outflow prevention valve comprising: a spring that biases the valve body in the nozzle direction; and a float that pushes the valve seat and the valve body in the nozzle direction by buoyancy via a valve shaft extended from the valve body. Configured. The float is composed of a cylindrical float body having an open bottom surface and a lid body that closes the top surface of the float body. At least a part of the lid body is composed of a magnetic body and is opposed to the magnetic body. And a permanent magnet that absorbs the magnetic body at a position where the valve seat is seated on the nozzle, and the sum of the elastic force of the spring and the attractive force is set stronger than the gravity of the valve body and the valve seat. I used the means. According to this means, when the liquid level of the liquefied gas in the evaporator is normal, the valve body and the valve seat are always separated from the nozzle against the elastic force of the spring, and the gas is supplied downstream. . The float pushes up the valve body and the valve seat in accordance with the liquid level, and when close to the seating position, the float is surely closed in combination with the force with which the permanent magnet attracts the magnetized body. Then, the valve closed state is maintained by the magnetic force of the permanent magnet, and even if the liquid level drops again, it does not return to automatic valve opening. The term “magnetized body” as used herein means a material that can be widely adsorbed by a permanent magnet. By adopting an inverted cup-like configuration for the float, the collapse of the float due to the hydraulic pressure does not occur.

  The liquefied gas outflow prevention valve is further provided with a reset shaft for pushing down the valve body and the valve seat from the seating position with respect to the nozzle to forcibly reset the valve closing state. Further, a float cover is provided on the outer periphery of the float to prevent the float from being sucked up to the nozzle side by the gas flow rate. The upper and lower sides of the float cover communicate with the container main body, so that the liquid pressure in the container is equal.

  As a more detailed means of the float, a concave portion is provided in the lower surface opening portion, and a weight added to the weight of the float can be attached to and detached from the concave portion, thereby freely adjusting the buoyancy of the float. In addition, a shaft is erected at the center of the recess, and a hole is formed in the center of the weight so that the shaft is inserted into the shaft. The weight is inserted into the shaft to fix the weight to the float. Using. With this means, it is easy to attach and fix weights. If the weight is lowered, an arbitrary number of weights can be fixed from a plurality of weights, and fine adjustment is possible.

  According to the present invention, when the liquid level of the liquefied gas in the container main body rises, the valve body and the valve seat are moved in the seating direction with respect to the nozzle by the buoyancy of the float, and reliably seat and supply gas to the downstream side. At the same time it can be stopped, the permanent magnet attracts the magnetized body, so even if the liquid level drops again, it will continue to maintain the valve closed state, and inadvertent valve opening will automatically occur as before Is no longer done. Moreover, since the float is hollow and the top is closed and the bottom is open, the float itself is crushed by the hydraulic pressure just by compressing the gas in the float even if the internal pressure of the cylinder is high. The float function can be exhibited normally in any situation.

  In addition, the configuration in which resetting is performed by the reset shaft makes it possible to easily return the valve once closed. And, when a float cover is provided on the outer periphery of the float and a guard pipe is provided to surround the outer periphery of the valve body and the valve seat, it is possible to prevent the float from being sucked upward by the gas flow rate, so that reliable operation It became possible to secure.

  Furthermore, since a recess is provided on the bottom surface of the float and a weight is attached to the recess, the buoyancy of the float can be adjusted, and precise valve control becomes possible. In addition, the weight is fixedly attached to the concave portion, and a shaft is erected in the concave portion, and an arbitrary number of donut-shaped weights are attached, so that precise buoyancy adjustment can be made possible.

  Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 shows one of the best embodiments of the present invention, in which gas is supplied to an apparatus such as an evaporator installed on the downstream side. Here, 1 is a container body of the evaporator, 2 is a container lid, 3 is a float that rises and falls depending on the liquid level, 4 is a float cover, and a structure for preventing the float 3 from being affected by the flow of liquefied gas. It is. 5 is a valve seat, 6 is a valve body, 7 is a valve seat, and 8 is a hole provided in the center of the valve seat 5, which functions as a liquefied gas nozzle. When the liquid level is normal, the valve seat 5 and the valve seat 7 are separated from each other as shown in the figure, so that they flow out from the gas outlet 9.

  FIG. 2 is an enlarged view showing in detail the vicinity of the shut-off valve, wherein 10 is a float cover upper plate on the upper surface of the float cover 4, 11 is a permanent magnet provided on the upper plate 10, and 12 is positioned above the float. A magnetizing portion 13 for connecting the valve body 6 and the float 3 and a valve shaft for raising and lowering the valve body 6 in synchronism with the movement of the float 3, and 14 for always moving the valve body 6 and the valve seat 7 upward. An energizing spring, 15 is a valve seat presser, and 16 is a guard pipe for regulating the valve body 6 to move up and down vertically. In addition, the float cover 4 shown in FIG. 1 is provided with a hole, and the inside of the float cover 4 is communicated with the container body 1 so that the liquid level is matched and the liquid pressure is made equal. The elastic force of the spring 14 is set to be weaker than the total gravity of the valve body 6, the valve seat 7, the valve shaft 13 and the float 3. Therefore, in the state of FIG. 1 where the liquid level is normal, the gravity of the valve body 6 overcomes the elastic force of the spring 14, so that the valve seat 7 is detached from the valve seat surface of the valve seat 5, and the liquefied gas is always downstream. Supplied to the side. In addition, the float 3 and the valve body 6 do not need to be combined, and if the valve body 6 can be pushed up when the float 3 rises due to a rise in the liquid level, it is physically configured as a separate body. Sometimes.

  As a specific configuration of the float 3, a lid 3 b that closes the upper opening is provided on the upper part of the cylindrical float body 3 a. The bottom surface is open and communicates with the outside. That is, the overall structure is such that the cup is turned upside down. The float body 3a is preferably made of stainless steel in consideration of rust prevention and strength, but is not particularly limited as long as it can overcome high temperature, high pressure, and chemical resistance to liquefied petroleum. However, since the material of the lid 3b needs to be magnetized to the permanent magnet 11 when the float 3 is raised, it needs to be a magnetic body. 3c is a recess provided on the bottom surface of the float, and a weight shaft 3d is erected downward on the axis. A weight 3e has a donut-shaped outer shape, and is fixed by inserting a center hole of the weight into the weight shaft 3d. The weight 3e is not limited to one, but a plurality of weights can be fixed, and the buoyancy of the float 3 is adjusted by the gravity of the weight 3e. In other words, finer buoyancy adjustment can be achieved by reducing the weight height by reducing the weight height.

  By the way, as shown in FIG. 1, when the liquefied petroleum gas is normally supplied to the outside, when the heat source is insufficient due to a power failure or the consumption of the liquefied gas reaches an abnormally high state, The liquid level in the container body 1 rises. Then, the buoyancy of the float 3 is increased, and a force is applied in the upward direction. That is, the lid body 3 b that is a magnetic body is gradually pushed up toward the permanent magnet 11. Then, the sum of the elastic force of the spring 14 and the buoyancy of the float 3 overcomes the total gravity of the valve body 6, the valve seat 7 and the valve shaft 13, and the valve seat 7 moves in the direction of seating on the valve seat 5. Further, when the lid 3b is close to the permanent magnet 11, the magnetizing force also acts greatly. When the lid 3b is close to a certain distance, the lid 3b is absorbed by the permanent magnet 11 and the valve seat 7 comes into contact with the valve seat 5. The valve is closed. Once the valve is closed, even when the liquid level drops again, the lid 3b is maintained while being attracted by the permanent magnet 11, so that it does not automatically return to the valve opening state. FIG. 3 shows a case where the float 3 is lifted to maintain the valve closed state.

  FIG. 4 further shows a structure for resetting from the state of FIG. 3, 20 is a valve cap, 21 is a reset shaft that can be raised and lowered through the center of the valve cap 20, and 22 is an upper end of the reset shaft 21. The provided reset knob 23 is a return spring that urges the reset shaft 21 in the extending direction. Reference numeral 24 denotes a boot for shielding the reset shaft 21 from being exposed. The lower end of the reset shaft 21 protrudes downward from the valve seat 5 by pushing the reset knob 22. FIG. 4 shows a state after the reset operation is completed. Here, when the liquid level rises to the state of FIG. 3, if no operation is performed, this state is maintained as described above. After that, if adjustment of the downstream combustion device is completed and it is confirmed that safe gas supply can be performed, first, the liquefied gas remaining in the container body 1 is discharged from the drain valve (not shown), If the reset knob 22 is pushed downward, the reset shaft 21 is pushed against the elastic force of the return spring 23, and the state in which the permanent magnet 11 and the lid 3b are magnetized is released. As a result, the valve body 6 and the valve seat 7 are both detached from the valve seat 5 and returned to the state shown in FIG. Then, if the liquefied gas is supplied into the container body 1 from the supply nozzle, the reset is completed.

  Furthermore, in FIG. 4, 25 is a magnet fixed to a part of the float 3, and 26 is a magnetic detector. The magnetic detection device 26 is attached to a part of the container body 1 of the evaporator, and is magnetic when either the float 3 is raised and closed, or when the float 3 is in the normal position. Is provided at a position where it can be detected. Specifically, the magnetic detection device 26 employs a switching member that operates according to a change in magnetic flux density, such as a reed switch, a Hall element, or a proximity switch. In this way, for example, by setting so that the signal is output when the float 3 is raised and in the valve-closed state, it is possible to quickly detect a malfunction that liquefied oil flows out regardless of this state. it can. Note that the state to be detected is not particularly limited. For example, if a plurality of magnetic detection devices 26 are installed in the vertical direction, it is possible to always detect the position of the float 3 that cannot be seen from the outside. For this magnetic detection, the structure of the float need not be limited to that of the present embodiment, and even the float illustrated as the background art can be applied as long as a magnet can be provided.

  The present invention can be widely used in an apparatus that supplies liquefied petroleum gas from a container such as a gas cylinder to an evaporator to generate gas.

End view showing one embodiment of the present invention Same as above, enlarged sectional view near the valve End view showing the valve closed state End view showing the state returned by reset

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Container body 2 Evaporator cover 3 Float 4 Float cover 5 Valve seat 6 Valve body 7 Valve seat 8 Hole (liquefied gas nozzle)
9 Gas outlet

Claims (6)

A nozzle for supplying the liquefied gas in the container main body to the downstream side, a valve seat and a valve body provided so as to be seated from the lower side of the nozzle, and a spring for biasing the valve seat and the valve body in the nozzle direction; A float that pushes the valve seat and the valve body in the direction of the nozzle by buoyancy via a valve shaft extended from the valve body. The float has a cylindrical float body with a bottom surface open, and the float body. And at least a part of the lid is made of a magnetic material, and is opposed to the magnetic material so that the magnetic material absorbs the magnetic material at a position where the valve seat is seated on the nozzle. The liquefied gas outflow is characterized in that the sum of the elastic force of the spring and the attractive force is set stronger than the gravity of the valve body and the valve seat. Check valve. The liquefied gas outflow prevention valve according to claim 1, further comprising a reset shaft for pushing down the valve body and the valve seat from the seating position with respect to the nozzle. The liquefied gas according to claim 1 or 2, wherein a float cover is provided on an outer periphery of the float to prevent the float from being sucked to the nozzle side by a gas flow rate, and the upper and lower sides of the float cover communicate with the container body. Spill prevention valve. The liquefied gas outflow prevention valve according to claim 1, wherein a concave portion is provided in a lower surface opening portion of the float, and a weight added to the weight of the float is detachable in the concave portion. 5. A shaft is erected at the center of the recess, and a hole through which the shaft is inserted is provided at the center of the weight, and the weight is fixed to the float by inserting the weight hole into the shaft. The liquefied gas outflow prevention valve as described. A nozzle for supplying the liquefied gas in the container main body to the downstream side, a valve seat and a valve body provided so as to be seated from the lower side of the nozzle, and a spring for biasing the valve seat and the valve body in the nozzle direction; A float that pushes the valve seat and the valve body in the direction of the nozzle by buoyancy through a valve shaft extended from the valve body, and a part of the upper surface of the float is made of a magnetic body. A permanent magnet that absorbs the magnetic material at a position where the valve seat is seated on the nozzle is provided, and another magnet is provided on a part of a side surface of the float. A liquefied gas outflow prevention valve provided with a magnetic detection device for detecting the magnetic field of the another magnet as it moves up and down.

Images