Abstract:
A device for controlling the release of gas from a pressurised container, the device comprising a plug comprising a passage therethrough, a diaphragm within said passage, wherein said diaphragm is configured to initially prevent flow of gas through said passage, and is rupturable or displaceable to allow gas to flow through said passage once said diaphragm is ruptured or displaced. The device further comprises a screw located within said plug and comprising a lance configured to move towards said diaphragm upon rotation of said screw, wherein said lance is configured to rupture or displace said diaphragm so as to allow flow of gas through said passage and out of said plug, once said screw is rotated a predetermined amount.

Description:
FOREIGN PRIORITY 
       [0001]    This application claims priority to United Kingdom Patent Application No. 1512627.9 filed Jul. 17, 2015, the entire contents of which is incorporated herein by reference. 
       FIELD 
       [0002]    The present disclosure relates generally to a device for controlling the release of gas from a pressurised container. 
       BACKGROUND 
       [0003]    Pressurised containers are used widely and in many applications. For example, in the fire and safety industry an inert gas may be held in a container at a raised pressure. The gas may be used to suppress a fire in an environment, such as a room or aircraft, or to inflate a safety device, such as an airbag. Typically, a valve is provided that controls the release of gas from the pressurised container to the environment. 
         [0004]    It has been found that in certain situations it may be necessary or desirable to depressurise such containers. What is desired, therefore, is an effective method of depressurising a container. 
       SUMMARY 
       [0005]    In accordance with the disclosure, there is provided an apparatus or device for controlling the release of gas from a pressurised container, the device comprising: a plug comprising a passage therethrough; a diaphragm within the passage, wherein the diaphragm is configured to initially prevent flow of gas through the passage, and is rupturable or displaceable to allow gas to flow through the passage once the diaphragm is ruptured or displaced; a screw located within the plug and comprising a lance configured to move towards the diaphragm upon rotation of the screw, wherein the lance is configured to rupture or displace the diaphragm so as to allow flow of gas through the passage and out of the plug, once the screw is rotated a predetermined amount; wherein optionally the plug, screw and diaphragm are removeable or replaceable as a single unit. That is, movement or removal of the plug causes automatic movement or removal of the screw and diaphragm. 
         [0006]    A device as described can be used as a simple and effective method of plugging a pressurised chamber, due to its consituent parts being removeable or replaceable as a single unit. Conventional devices may, for example, use a diaphragm that is separate to the plug, which is not as easy to use. Further features are described below that have additional advantages over conventional devices for controlling the release of gas from pressurised containers. 
         [0007]    The plug may be configured to plug an outlet of a pressurised container. The device may consist of the plug, diaphragm and screw. The diaphragm may be welded to the plug. The diaphragm may be located at an end of the plug and/or passage that is locatable within an outlet of a pressurised container, or is located within the outlet of said pressurised container. 
         [0008]    The lance may comprise a non-circular transverse cross-section. For example, the lance may comprise a triangular, square, pentagonal, hexagonal, elliptical, parabolic, hyperbolic, or polygonal transverse cross-section. The transverse cross-section may comprise a closed plane figure or shape having three or more sides. 
         [0009]    The non-circular transverse cross-section may be provided along a majority of the length of the lance. The lance may comprise a pointed end portion, e.g. a sharpened tip, for intially rupturing or displacing the diaphragm. The lance may further comprise a non-circular transverse cross-section along the entirety of its length, with the exception of the pointed end portion, or including the pointed end portion. 
         [0010]    The non-circular transverse cross-section may change as one moves along the length of the lance. For example, the transverse cross-section may be square until the pointed end portion, at which point the transverse cross-section becomes rectangular, wherein the rectangle becomes progressivley smaller until the tip or end of the lance. 
         [0011]    The passage and/or the screw may be coaxial with a longitudinal axis of the plug. The plug and/or passage and/or screw may be axially symmetric. The axis in question may be the longitudinal axis of the plug, passage or screw respectively. 
         [0012]    The screw may be rotatable to a given distance into the plug, wherein at the given distance the diaphragm is ruptured or displaced and gas is able to flow through the passage and out of the plug. The given distance may be the point at which the diaphragm is configured to rupture or displace. 
         [0013]    The screw may be rotatable to a maximum distance into the plug, wherein at the maximum distance gas is able to flow through the passage and out of the plug. 
         [0014]    The passage may comprise a first portion having a relatively small diameter and a second portion having a relatively large diameter that comprises a threaded portion. 
         [0015]    The screw may comprise a lance portion having a relatively small diameter and comprising the lance, and a threaded portion having a relatively large diameter that is configured to cooperate with the threaded portion of the passage. 
         [0016]    The device may comprise one or more gas paths or outlets that extend from the first portion of the passage to an outer surface of the plug for discharging gas from the first portion of the passage to an external environment. The outlets may be arranged such that there is substantially no net lateral force on the plug as gas escapes from the plug in use. For example, where two outlets are provided, these may extend laterally from the central passage and may be located opposite one another. The central passage may be symmetrical about a central and/or longitudinal axis of the plug. 
         [0017]    The diaphragm may be located within the first portion of the passage, and may be located at an end of the first portion of the passage, for example an end configured to be located within an outlet of a pressurised container. 
         [0018]    The lance portion of the screw may extend into the first portion of the passage. 
         [0019]    The screw may be rotatable relative to the plug, and may be removable from the plug. 
         [0020]    In accordance with an aspect of the disclosure, there is provided an apparatus comprising: a pressurised container having a gas outlet; a device as described above and located at least partially within the outlet so as to initially prevent gas flow out of the outlet; wherein upon rupturing or displacing the diaphragm, gas is configured to flow out of the outlet and into an external environment via the passage. 
         [0021]    The container may comprise a main outlet and an auxiliary outlet. The device or plug may be located at least partially within the auxiliary outlet, so as to initially prevent and/or control gas flow out of the auxiliary outlet. 
         [0022]    The container may comprise an outlet valve. The device or plug may be located at least partially within the outlet valve. The outlet valve may comprise a main outlet and an auxiliary outlet, and the device or plug may be located within the auxiliary outlet so as to prevent and/or control an auxiliary gas flow out of the auxiliary outlet. The device may be used to plug or seal part of the outlet valve that is configured to be exposed to the pressure of the container, e.g. before a sealing mechanism or other device within the valve that prevents the contents of the container escaping through the main outlet. In this case the device as described herein would provide an easy manner in which to depressurise the container, without having to release its contents through the main outlet. 
         [0023]    In accordance with the disclosure, there is provided an apparatus or device for controlling the release of gas from a pressurised container, the device comprising: a plug comprising a passage therethrough; a diaphragm within the passage, wherein the diaphragm is configured to initially prevent flow of gas through the passage, and is rupturable or displaceable to allow gas to flow through the passage once the diaphragm is ruptured or displaced; a screw located within the plug and comprising a lance configured to move towards the diaphragm upon rotation of the screw, wherein the lance is configured to rupture or displace the diaphragm so as to allow flow of gas through the passage and out of the plug, once the screw is rotated a predetermined amount; wherein the screw may be rotatable to a maximum distance into the plug, and at the maximum distance gas is able to flow through an outlet passage and out of the plug, for example to an external environment. 
         [0024]    In accordance with the disclosure, there is provided a kit for controlling the release of gas from a pressurised container, the kit comprising: a plug comprising a passage therethrough; a diaphragm within the passage, wherein the diaphragm is configured to initially prevent flow of gas through the passage, and is rupturable or displaceable to allow gas to flow through the passage once the diaphragm is ruptured or displaced; a first screw or bolt locatable within the passage, wherein the length of the first screw or bolt is such that it cannot contact the diaphragm in use; a second screw locatable within said plug and comprising a lance configured to move towards said diaphragm upon rotation of said second screw, wherein said lance is configured to rupture or displace said diaphragm so as to allow flow of gas through said passage and out of said plug, once said second screw is rotated a predetermined amount. 
         [0025]    The length of the first screw or bolt may be relative to the length of the passage. For example, if the passage is X cm and the diaphragm is located at the end of the passage, then the first screw or bolt should be less than X cm in length, or X−1 cm in length. 
         [0026]    The kit may comprise a container or valve having an outlet, and the plug may be configrured to be inserted into and/or seal the outlet. The plug and outlet may have cooperating features, such as screw threads, to effectuate the seal. 
         [0027]    In accordance with an aspect of the disclosure, there is provided a method of using the device or the apparatus as described above, the method comprising: rotating the screw relative to the plug to an extent that will cause the lance of the screw to rupture or displace the diaphragm to allow gas to flow out of the outlet and into an external environment via the passage. 
         [0028]    In accordance with an aspect of the disclosure, there is provided a device for controlling the release of gas from a pressurised container, the device comprising: a plug comprising a passage therethrough; a diaphragm within said passage, wherein said diaphragm is configured to initially prevent flow of gas through said passage, and is rupturable or displaceable to allow gas to flow through said passage once said diaphragm is ruptured or displaced; a screw located within said plug and comprising a lance configured to move towards said diaphragm upon rotation of said screw, wherein said lance is configured to rupture or displace said diaphragm so as to allow flow of gas through said passage and out of said plug, once said screw is rotated a predetermined amount; wherein said lance comprises a non-circular transverse cross-section. 
         [0029]    For example, the lance may comprise a triangular, square, pentagonal, hexagonal, elliptical, parabolic, hyperbolic, or polygonal transverse cross-section. The transverse cross-section may comprise a closed plane figure or shape having three or more sides. 
         [0030]    The non-circular transverse cross-section may be provided along a majority of the length of the lance. The lance may comprise a pointed end portion, e.g. a sharpened tip, for intially rupturing or displacing the diaphragm. The lance may further comprise a non-circular transverse cross-section along the entirety of its length, with the exception of the pointed end portion, or including the pointed end portion. 
         [0031]    The non-circular transverse cross-section may change as one moves along the length of the lance. For example, the transverse cross-section may be square until the pointed end portion, at which point the transverse cross-section becomes rectangular, wherein the rectangle becomes progressivley smaller until the tip or end of the lance. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0032]    Various embodiments will now be described, by way of example only, and with reference to the accompanying drawings in which: 
           [0033]      FIG. 1  shows a side view of a plug in accordance with an embodiment; 
           [0034]      FIG. 2  shows a top view of the plug of  FIG. 1   
           [0035]      FIG. 3A  shows a cross-section as indicated in  FIG. 1 ; 
           [0036]      FIG. 3B  shows an alternative embodiment to  FIG. 3A ; 
           [0037]      FIG. 3C  shows a cross-section as indicated in  FIG. 3B   
           [0038]      FIG. 4  shows a further side view of the plug of  FIG. 1 ; and 
           [0039]      FIG. 5  shows a cross-section as indicated in  FIG. 4 . 
       
    
    
     DETAILED DESCRIPTION 
       [0040]    An embodiment is shown with reference to  FIGS. 1-5 . 
         [0041]      FIG. 1  shows a side view of a device comprising a plug  10  that may be arranged and adapted to fit into an outlet of a container (not shown) for holding a substance, for example a gas at a raised pressure. 
         [0042]    A first portion  12  of the plug  10  may be configured to extend into an outlet such that it may form a seal and prevent gas from escaping the container. The first portion  12  may comprise a first end  11  of the plug  10 . The first portion  12  of the plug  10  may have an interference, press or snap fit arrangement with the container, or could be provided with a threaded portion to allow the plug  10  to screw into an outlet of a pressurised container. 
         [0043]    A sealing engagement may be present between an outer surface of the first portion  12  and the outlet. For example, one or more washers may be provided to fit between and seal the outer surface of the first portion  12  and the container, or cooperating threaded portions could be provided on the outer surface of the first portion  12  and the container. 
         [0044]    A second portion  14  of the plug may be configured to remain exterior to the outlet, and can comprise a shoulder or surface  15  that may be configured to rest on the exterior of the container when the first portion  12  of the plug  10  is inserted into the outlet. The second portion  14  may comprise a second end  13  of the plug  10 , which may be opposite the first end  11 . 
         [0045]      FIG. 2  shows a top view of the second portion  14  of the plug  10 . 
         [0046]    The second portion  14  may be substantially hexagonal, and may comprise six flat portions  16  and/or six rounded edges  17 . However, the second portion  14  can be of any shape or size as is desired for any particular application. From the top view of  FIG. 2  it can be seen that a screw  20  may be located within the plug  10  and this will be described in more detail below. 
         [0047]      FIG. 3A  shows an axial cross-section through the plug  10  of  FIG. 1 . 
         [0048]    The device or plug  10  may comprise an internal passage  30  that may extend through the plug  10  from the first end  11  to the second end  13 . The screw  20  may be located within part of the internal passage  30 . The internal passage  30  may comprise a first portion  32  having a first, relatively small internal diameter, as well as a second portion  34  having a second, relatively large internal diameter. The second portion  34  may comprise a threaded portion  36  along at least part of its length. 
         [0049]    The screw  20  may comprise a threaded portion  22  that may cooperate with the threaded portion  36  of the internal passage  30 . The screw  20  may further comprise an elongate portion  24  that extends along the internal passage  30  and ends in a sharpened tip  26 . The elongate portion  24  may be cylindrical such that it has a circular transverse cross-section, i.e. perpendicular to the longitudinal axis of the elongate portion  24 . 
         [0050]    In various embodiments the elongate portion may comprise a non-circular or irregular transverse cross-section. For example, the elongate portion  24  may comprise a triangular, square, pentagonal, hexagonal, elliptical, parabolic or hyperbolic transverse cross-section. An example is shown in  FIGS. 3B and 3C , in which the elongate portion  24  has a square transverse cross-section. 
         [0051]    Provision of a non-circular cross-section means that gas may be allowed to escape through the diaphragm as the elongate portion protrudes through it, as described below. This may not be possible, or may be more difficult with a cylindrical elongate portion  24  since the sides of the elongate portion  24  can form a complete seal as it rotates. 
         [0052]    A cavity  28  (see also  FIG. 2 ) may be provided on the end of the screw  20  opposite the tip  26 . The cavity  28  may be in the form of a slot, cross, recessed square or other shape. This can allow a screwdriver to be used to turn the screw  20 , for example a flat-head screwdriver or Phillips screwdriver. 
         [0053]    Rotation of the screw in a first, e.g. clockwise direction may cause the screw  20  to move further into the plug  10  towards the first end  11 . Rotation of the screw  20  in a second, e.g. anticlockwise direction may cause the screw to move in the opposite direction, out of the plug  10 . The reverse arrangement is also possible. 
         [0054]    The device may comprise a rupturable or displaceable diaphragm  40 . The diaphragm  40  may initially provide a sealing function, for example to prevent gas from escaping the container through the internal passage  30 . The plug  10 , screw  20  and diaphragm  40  may all be part of a single unit that is replaceable and/or removable as a single unit. This provides a simple apparatus or means for plugging an outlet of a container whilst providing a controlled release of gas therefrom, as described below. 
         [0055]    It has been found that certain situations may require the gas to be released from the container manually, and in a controlled manner. The technology of the present disclosure provides such a functionality and an example is shown in  FIGS. 1-5 . 
         [0056]    As can be appreciated from  FIG. 3 , as the screw  20  is turned in a first direction it may eventually contact the diaphragm  40 . Further turning of the screw  20  may cause the tip  26  to puncture and/or displace the diaphragm  40  and may allow gas to release from the container into the internal passage  30 . 
         [0057]    The diaphragm  40  can be made of a material that is softer than that of the screw  20 , or the tip  26  of the screw  20 . For example, the screw  20  or tip  26  can be a first metal, whilst the diaphragm may be second metal, wherein the second metal is softer than the first metal. This can allow easy penetration of the diaphragm  40  by the screw  20 . The diaphragm  40  may, alternatively or additionally, comprise lines of weakness that may be positioned so as to be scored by the tip  26  as it advances. The diaphragm may be held in place by an interference, press or snap fit arrangement, wherein the force of the screw is not sufficient to displace the diaphragm. Rather, the diaphragm  40  may be punctured as the screw  20  advances towards and through it. The diaphragm  40  may be integral with the body of the plug  10 . 
         [0058]    Other embodiments are contemplated in which the diaphragm  40  may be displaced, rather than ruptured by the screw  20 . For example, the diaphragm  40  may be held in place by an interference, press or snap fit arrangement with the end  11  of the plug  10 , and the tip  26  of the screw  20  could be configured to push or displace the diaphragm out of such an arrangement to allow gas to be released from the container. 
         [0059]    Gas may be released from the internal passage  30  into the external environment via one or more outlets  38 . The one or more outlets  38  may be provided that allow gas to be released immediately once the diaphragm  40  is ruptured. Any number of outlets  38  can be provided, and in any orientation or arrangement as necessary for any particular application. The outlets  38  may be arranged opposite each other or in some other arrangement that ensures there is no net force as a result of the gas exiting the outlets. 
         [0060]    The one or more outlets  38  may be located within the second portion  14  of the plug (see  FIG. 1 ) and/or can bridge both the first portion  32  and second portion  34  of the internal passage  30 . In this manner, even if the screw  20  is rotated to its maximum extent, i.e. as far as it can travel towards the first end  11  where the diaphragm is located, gas can still escape through the outlets  38  since they are at least partially located in the first passage  32 . 
         [0061]    The device or apparatus as described herein may be used to plug or seal an outlet to a container (not shown). The outlet may be an auxiliary outlet, i.e. secondary to a main outlet or valve that is connected to, e.g. a fire suppression network or another device, for example an inflatable device such as an airbag. Pressurised containers may be provided with such auxiliary outlets to relieve pressure in the container if this is desired, without having to release the gas through the primary outlet or valve to deploy fire suppressant or activate a device (e.g. an airbag). 
         [0062]    The device or apparatus as described herein may also be used to plug or seal part of an outlet valve that is for controlling the release of gas from a pressurised container. In these embodiments, the device could be used to plug or seal part of the outlet valve that is configured to be exposed to the pressure of the container, e.g. before a sealing mechanism within the valve. The plug would provide an easy manner in which to depressurise a container that the valve is connected to, without having to operate the valve. 
         [0063]    The plug as described herein may also be used to plug or seal part of an outlet of a gassing device, for example a device configured to release gas at a high rate. The plug may be used to safely depressurise such a device. 
         [0064]    The plug, diaphragm and screw could be provided as part of a kit. In this case a first screw could be provided that is locatable in the plug, as well as a second screw, wherein the second screw corresponds to the screw comprising a lance described above. The first screw could have a length such that it cannot contact the diaphragm in use. In this manner, the first screw could be used as a safety or ‘dummy’ screw that cannot puncture or displace the diaphragm. When it is desired to depressurise a container or valve into which the plug is inserted, the first screw can be replaced with the second screw and operated as described herein. 
         [0065]    Although the present invention has been described with reference to preferred embodiments, it will be understood by those skilled in the art that various changes in form and detail may be made without departing from the scope of the invention as set forth in the accompanying claims.