WO2013164842A2

WO2013164842A2 - Temperature activated shut off mechanism

Info

Publication number: WO2013164842A2
Application number: PCT/IN2013/000151
Authority: WO
Inventors: Jayant MATKAR; Mangesh MOGHE
Original assignee: Gas Safe India Marketing
Priority date: 2012-03-12
Filing date: 2013-03-12
Publication date: 2013-11-07
Also published as: WO2013164842A3

Abstract

A temperature activated shut off mechanism for a valve is disclosed. The temperature activated shut off mechanism includes a plunger, a spring, a nut, a fusible block and a closing element. The spring configures a compressed and a de-compressed configuration. The closing element prevents flow of gas out of the temperature activated shut off mechanism in the de-compressed configuration of the spring. In a gas flow configuration of the temperature activated shut off mechanism, the spring is in compressed configuration between the inner surface of the valve and the nut and the gas flows out of the temperature activated shut off mechanism. In a gas blocking configuration, when temperature exceeds a predetermined limit then the fusible block melts causing the spring to form the de-compressed configuration and thereby activating the closing element to prevent flow of gas out of the temperature activated shut off mechanism.

Description

TEMPERATURE ACTIVATED SHUT OFF MECHANISM

FIELD OF THE DISCLOSURE

The present disclosure generally relates to safety devices used for Liquefied Petroleum Gas (LPG) cylinders.

Particularly, the present disclosure relates to a temperature activated shut off mechanism for safety devices/excess flow shut off valve, typically for Liquefied Petroleum Gas (LPG) cylinders. The temperature activated shut off mechanism can be used for any type of valve and can be designed for any temperature range.

BACKGROUND

Liquefied petroleum gas (LPG) is a flammable mixture of hydrocarbon gases used as a fuel. LPG is generally stored in a cylinder under pressure. Various safety devices such as a regulator, a safety cap and the like are installed on a cylinder for facilitating safe and effective working of LPG.

Although, various prior art safety devices provide safe operation of LPG, these prior art safety devices are either ineffective or fail during high temperature environment, such as fire. In high temperature environment, such as fire, the temperature generated is very high. In such high temperature environment, outflow of LPG through a LPG cylinder may further create havoc and increase the level of destruction. Accordingly, there is need of a safety device for LPG cylinders that prevents outflow of LPG through a LPG cylinder in high temperature environment, such as fire. Also, there is need of a safety device for LPG cylinders that is easy to use. Additionally, there is need of a safety device for LPG cylinders that can be fitted to the existing fitting arrangements of a LPG cylinder. Further, there is need of a safety device for LPG cylinders that is cost effective. Furthermore, there is need of a safety device for LPG cylinders that is reliable.

OBJECTS

Some of the objects of the system of the present disclosure which at least one embodiment herein satisfies are as follows:

It is an object of the system of the present disclosure to ameliorate one or more problems of the prior art or to at least provide a useful alternative.

An . object of the present disclosure is to provide a safety device for LPG cylinders that prevents outflow of LPG from the LPG cylinders during high temperature environment, such as fire.

Also, an object of the present disclosure is to provide a safety device for LPG cylinders that is easy to use.

Additionally, an object of the present disclosure is to provide a safety device for LPG cylinders that can be fitted to the existing fitting arrangements of the LPG cylinders. Another object of the present disclosure is to provide a safety device for LPG cylinders that is cost effective.

Further, an object of the present disclosure is to provide a safety device for LPG cylinders that is reliable.

Furthermore, an object of the present disclosure is to provide a safety device for LPG cylinders that prevents excess flow of LPG beyond a pre-determined limit from LPG cylinders.

Other objects and advantages of the system of the present disclosure will be more apparent from the following description when read in conjunction with the accompanying figures, which are not intended to limit the scope of the present disclosure.

SUMMARY

In accordance with one aspect of the present disclosure, a temperature activated shut off mechanism for a valve is disclosed. The temperature activated shut off mechanism includes a plunger, a spring, a nut, a fusible block and a closing element. The spring is disposed on a first side of the plunger and abuts an inner surface of the valve. The spring is adapted to configure a compressed and a decompressed configuration. The nut is disposed on the first side of the plunger before the spring and functionally connected to the spring. The fusible block disposed on the first side of the plunger before the nut and functionally connected to the nut. The closing element is disposed on a second side of the plunger and adapted to prevent flow of gas out of the temperature activated shut off mechanism in the de-compressed configuration of the spring. In a gas flow configuration of the temperature activated shut off mechanism, the spring is in compressed configuration between the inner surface of the valve and the nut and in the gas flow configuration, the gas flows out of the temperature activated shut off mechanism. In a gas blocking configuration, when temperature exceeds a predetermined limit then the fusible block melts causing the spring to form the de-compressed configuration and thereby activating the closing element to prevent flow of gas out of the temperature activated shut off mechanism.

Typically, the fusible block has a plurality of holes configured thereon for facilitating flow of gas there through.

Typically, the fusible block is of alloy.

In one embodiment, a spacer is functionally connected to the fusible block.

Further, the spacer is of brass.

In one embodiment, the closing element is of rubber.

In one embodiment, the closing element has a conical shape.

Alternatively, in another embodiment, a connector is provided for facilitating connection of a gas regulator to the valve with the temperature activated shut off mechanism.

In another aspect of the present disclosure, a valve for LPG cylinders is disclosed. The valve includes a temperature activated shut off mechanism. The temperature activated shut off mechanism includes a plunger, a spring, a nut, a fusible block and a closing element. The spring is disposed on a first side of the plunger and abuts an inner surface of the valve. The spring is adapted to configure a compressed and a de-compressed configuration. The nut is disposed on the first side of the plunger before the spring and functionally connected to the spring. The fusible block is disposed on the first side of the plunger before the nut and functionally connected to the nut. The closing element is disposed on a second side of the plunger and adapted to prevent flow of gas out of the temperature activated shut off mechanism in the de-compressed configuration of the spring. In a gas flow configuration of the temperature activated shut off mechanism, the spring is in compressed configuration between the inner surface of the valve and the nut and in the gas flow configuration, the gas flows out of the temperature activated shut off mechanism. In a gas blocking configuration, when temperature exceeds a predetermined limit then the fusible block melts causing the spring to form the de-compressed configuration and thereby activating the closing element to prevent flow of gas out of the temperature activated shut off mechanism.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS

The temperature activated shut off mechanism of the present disclosure will now be explained in relation to the non-limiting accompanying drawings, in which:

FIGURE 1 illustrates an exploded perspective view of a temperature activated shut off mechanism;

FIGURE 2 illustrates an exploded sectional view of the temperature activated shut off mechanism of Figure 1 ; FIGURES 3 and 4 illustrate perspective views of a valve assembled with temperature activated shut off mechanism of Figure 1 ;

FIGURE 5 illustrates an assembled sectional view of the valve with temperature activated shut off mechanism of Figure 1 ;

FIGURES 6a illustrates a sectional view of the temperature activated shut off mechanism of Figure 1 depicting open position of the temperature activated shut off mechanism;

FIGURE 6b illustrates a sectional view of an encircled portion "A" shown in Figure 6a;

FIGURES 7a illustrates a sectional view of the temperature activated shut off mechanism of Figure 1 depicting shut off position of the temperature activated shut off mechanism; and

FIGURE 7b a sectional view of an encircled portion "B" shown in Figure 7a.

DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The temperature activated shut off mechanism of the present disclosure will now be described with reference to the accompanying drawings which do not limit the scope and ambit of the disclosure. The description provided is purely by way of example and illustration.

The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.

The description hereinafter, of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

The present disclosure provides a temperature activated shut off mechanism for providing enhanced security to LPG cylinders. More specifically, a temperature activated shut off mechanism of the present disclosure prevents outflow of LPG from LPG cylinders during high temperature environment, such as fire. Accordingly, a temperature activated shut off mechanism of the present disclosure prevents further deterioration -of the high temperature environment. Further, a temperature activated shut off mechanism of the present disclosure is easy to use and can be fitted to existing fitting arrangements of a LPG cylinder.

Referring to Figures 1 to 7b, a complete valve with temperature activated shut off mechanism 100 is disclosed in one embodiment. The temperature activated shut off mechanism of valve 100 includes a body portion 102, a spring 104, a nut 106, a fusible block 108, a spacer 1 10, a plunger 1 12, a closing element 1 14, a connector 1 16, a connector o-ring 1 18 (shown in Figure 2) and a joint packing 120 (shown in Figure 2).

The spring 104 is disposed on a first side 122 (illustrated in Figure 2) of the plunger 1 12 and abutting an inner surface of the valve. More specifically, the spring 104 is abutting an inner surface of the body portion 102 of the valve. The spring 104 is adapted to configure a compressed and a de-compressed configuration. The spring 104 and the nut 106 are mounted on the plunger 1 12 on the first side 122. The nut 106 is disposed on the first side 122 of the plunger 1 12 before the spring 104 and functionally connected to the spring 104. The fusible block 108 is disposed on the first side 122 of the plunger 1 12 before the nut 106. The fusible block 108 is functionally connected to the nut 106. In one embodiment, the fusible block 108 is of alloy.

The spacer 1 10 is functionally connected to the fusible block 108. In one embodiment, the spacer 1 10 is of brass. However, the present invention is not limited to any particular material used for manufacturing the spacer 1 10. The closing element 1 14 is disposed on a second side 124 of the plunger 1 12 and adapted to prevent flow of gas out of the temperature activated shut off mechanism in the de-compressed configuration of the spring 104. In one embodiment, the closing element 1 14 has a conical shape. However, the present disclosure is not limited to any particular shape of the closing element 1 14. In another embodiment, the closing element 1 14 is of rubber. However, the present disclosure is not limited to any particular material used for manufacturing the closing element 1 14.

Generally, when the LPG flows through the valve, in a gas flow configuration, with the temperature activated shut off mechanism 100, the spring 104 is in compressed configuration between the inner surface of the body portion 102 and the nut 106. The spring 104 is disposed on one side of the nut 106 and the fusible block 108 and the spacer 1 10 is disposed on the other side of the fusible block 108. The fusible block 108, mounted on the plunger 1 12, is in physical communication with the nut 106 and the spacer 1 10. In one embodiment, the fusible block 108 has four holes for allowing passage of LPG from a LPG cylinder to a LPG stove.

The valve with temperature activated shut off mechanism 100 is installed on a LPG cylinder valve. Then, a LPG regulator is fitted to the connector 1 16 of the valve with temperature activated shut off mechanism 100. The LPG regulator is connected to a LPG stove by means of a hose/ pipe. During normal conditions of working, LPG passes through the temperature activated shut off mechanism of the valve 100, via the route of a LPG Cylinder- the fusible block 108 - the spacer 1 10 - the connector 1 16 - a LPG regulator- a LPG stove, as illustrated in Figures 5, 6a and 6b. The alphabet "G" denotes flow of LPG from a LPG cylinder to a LPG stove.

In case of high temperature environment, such as fire, when the temperature of the valve with temperature activated shut off mechanism 100 increases beyond the predetermined limit, in a gas blocking configuration, then the fusible block 108 melts causing the spring 104 to form the de-compressed configuration, to push the sub assembly consisting of the nut 106, the plunger 1 12 and the closing element 1 14 on the connector 1 16 hence shutting off the flow of gas. The shut off position of the temperature activated shut off mechanism 100 is denoted by the alphabet "S" (shown in Figure 7a). More specifically, the closing element 1 14 blocks the passage of LPG from a LPG cylinder to a LPG regulator and thereby to an outside environment. Thereby, the valve with temperature activated shut off mechanism 100 prevents further deterioration of the high temperature environment.

In one embodiment, the valve with temperature activated shut off mechanism 100 prevents outflow of LPG from LPG cylinders at a temperature in the range of 1 19 to 149° C. In other words, the fusible block 108 is adapted to melt in the range of 1 19 to 149° C. However, the present disclosure is not limited to any particular temperature/ temperature range.

Further, the valve with temperature activated shut off mechanism 100 prevents excess flow of LPG beyond a pre-determined limit from a LPG cylinder. More specifically, the valve with temperature activated shut off mechanism 100 prevents excess flow LPG beyond a pre-determined limit that may occur due to any reason. The excess flow preventing mechanism includes a Ball (not shown) that may sit on an O-Ring (not shown) and shuts off excess LPG flow from LPG cylinders.

Test Analysis

1. The activation temperature of the temperature activated shut off mechanism, during the trials carried out in house was between 124 to 130 Degrees C and the temperature range between which the shut off must take place was 1 16 Degrees C to 149 Degrees C.

2. Three samples of each cylinder connection device were decided to be subjected to this test. The appliance portion was connected to the cylinder portion and the cylinder portion connected to an air supply maintained at 375 psig (2.6 MPa). The outlet of the appliance portion was connected to a piping system that includes a regulator and a flow meter adjusted for 35 scfh (1.00 m3/h) or 80 percent of the flow limiting device activation flow, when 35 scfh (1.0 m3/h) was not capable of being obtained. Each sample, in turn, was to then be immersed in an oil bath and the outlet from the piping system is to be connected to tubing that was immersed in water. The temperature of the entire oil bath with submerged sample was raised to 104°C (220°F) and stabilized. The temperature of the oil bath is to be slowly increased at a rate not greater than 0.5°C (10°F) per minute until the heat sensitive element shuts off the flow of air through the sample. The temperature of activation is to be recorded. No air flow through the device shall be observed after activation.

Fire Test

1. This test was conducted in a controlled environment for both safely and to prevent air flow or breezes from affecting the results.

2. A cylinder portion was connected to an air or nitrogen supply line containing a regulator, a flow meter, and a pressure gauge. The appliance portion was connected to a piping system containing a control valve with the outlet tubing being immersed in water.

3. A pan approximately 3 inches (76 mm) in diameter and 1 inch (25 mm) high was filled approximately 3/4 full of kerosene and located so it was centered under the thermal activation area of the device. The surface of the kerosene was 2 inches (51 mm) below the center line of the outlet of the cylinder portion of the connection device.

4. Four samples of the appliance portion were tested. The appliance portion was connected to the cylinder portion as intended in service. Two samples were tested with 25 psig (172 kPa) inlet pressure one with the flow limiting device in bypass and the other flowing 35 scfh (1.0 m3/h) or 80 percent of the flow limiting device activation flow when 35 scfh (1.0 m3/h) could not be obtained. Two samples were tested at 250 psig (1.7 MPa) or the rated operating pressure if greater, one with the flow limiting device in bypass and other flowing 35 scfh (1.0 m3/h) or 80 percent of the flow limiting device activation flow when 35 scfh (1.0 m3/h) was not capable of being obtained.

5. The regulator and control valve was adjusted to attain the specified pressure and flow, the control valve was fully open for the bypass flow tests. The pan of kerosene was ignited and the elapsed time to thermal shutoff recorded. Thermal shut off were occurred within five minutes. The flame was extinguished and the flow meter and outlet tube observed for 30 seconds. No flow was observed.

TECHNICAL ADVANCEMENTS AND ECONOMICAL SIGNIFICANCE

The technical advancements offered by the system of the present disclosure which add to the economic significance of the disclosure include the realization of: • a temperature activated shut off mechanism of the valve for LPG cylinders that prevents outflow of LPG during high temperature environment, such as fire;

• a valve, with temperature activated shut off mechanism, for LPG cylinders that is easy to use;

• a temperature activated shut off mechanism incorporated in an excess flow shut off valve for LPG cylinders that. can be fitted to the existing fitting arrangements of LPG cylinders;

• a valve, with temperature activated shut off mechanism, for LPG cylinders that is cost effective;

• a valve, with temperature activated shut off mechanism, for LPG cylinders that is reliable; and

• a valve, with temperature activated shut off mechanism, for LPG cylinders that prevents excess flow of LPG beyond a pre-determined limit from the LPG cylinders.

Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps. The use of the expression "at least" or "at least one" suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment to achieve one or more of the desired objects or results.

Any discussion of documents, acts, materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.

The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.

Claims

Claims:

1. A temperature activated shut off mechanism for a valve, said mechanism comprising:

• a plunger;

• a spring disposed on a first side of said plunger and abutting an inner surface of said valve and adapted to configure a compressed and a de-compressed configuration;

• a nut disposed on said first side of said plunger before said spring and functionally connected to said spring;

• a fusible block disposed on said first side of said plunger before said nut and functionally connected to said nut; and

• a closing element disposed on a second side of said plunger and adapted to prevent flow of gas out of said temperature activated shut off mechanism in said de-compressed configuration of said spring,

wherein in a gas flow configuration of said temperature activated shut off mechanism, said spring is in compressed configuration between said inner surface of said valve and said nut and in said gas flow configuration the gas flows out of said temperature activated shut off mechanism, and wherein in a gas blocking configuration, when temperature exceeds a predetermined limit then said fusible block melts causing said spring to form said de-compressed configuration and thereby activating said closing element to prevent flow of gas out of said temperature activated shut off mechanism.

2. The temperature activated shut off mechanism as claimed in claim 1, wherein said fusible block has a plurality of holes configured thereon for facilitating flow of gas there through.

3. The temperature activated shut off mechanism as claimed in claim 1, wherein said fusible block is of alloy.

4. The temperature activated shut off mechanism as claimed in claim 1, wherein said closing element is of rubber.

5. The temperature activated shut off mechanism as claimed in claim 1, wherein said closing element has a conical shape.

6. The temperature activated shut off mechanism as claimed in claim 1, further comprising a connector for facilitating connection of a gas regulator to said valve with said temperature activated shut off mechanism

7. The temperature activated shut off mechanism as claimed in claim 1, further comprising a spacer functionally connected to said fusible block.

8. The temperature activated shut off mechanism as claimed in claim 7, wherein said spacer is of brass.

9. A valve for LPG cylinders, said valve comprising:

• a temperature activated shut off mechanism comprising:

o a plunger;

o a spring adapted to configure a compressed and a decompressed configuration and disposed on a first side of said plunger and abutting an inner surface of said valve;

o a nut disposed on said first side of said plunger before said spring and functionally connected to said spring; o a fusible block disposed on said first side of said plunger before said nut and functionally connected to said nut; and o a closing element disposed on a second side of said plunger and adapted to prevent flow of gas from said temperature activated shut off mechanism in said de-compressed configuration of said spring,

wherein in a gas flow configuration of said temperature activated shut off mechanism, said spring is in compressed configuration between said inner surface of said valve and said nut and in said gas flow configuration the gas flows out of said temperature activated shut off mechanism, and

wherein in a gas blocking configuration, when temperature exceeds a predetermined limit then said fusible block melts causing said spring to form said de-compressed configuration and thereby activating said closing element to prevent flow of gas out of said temperature activated shut off mechanism.