Abstract:
A portable or wheeled fire extinguishing apparatus which is operable by water or foam, comprising a pressure resistant extinguishing medium container, a pressurized gas bottle for pressurizing the extinguishing medium container for expelling the extinguishing medium, and an extinguishing medium gun which is connected to the extinguishing medium container by a pressure resistant hose, wherein additional pressurized gas can be introduced into the extinguishing medium supplied to the extinguishing medium gun.

Description:
[0001]    This is a continuation-in-part application of pending international patent application PCT/DE2011/001138 filed May 30, 2011 and claiming the priority of German patent application 10 2010 022 789.7 filed Jun. 4, 2010. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    Portable or wheeled fire extinguishers with liquid extinguishing mediums, namely water or foam, are known. Also, fire extinguishers in the form of foam extinguishers producing pressurized gas-solidified foam extinguishers are known. 
         [0003]    EP 1 197 245 A1 discloses a portable or wheeled fire extinguisher which operates with pressurized gas-solidified foam and which achieves an improved foam solidification in that between the extinguishing medium hose and the extinguishing gun a mixing armature is installed to which a pressurized gas line is connected that is connected via a pressurized gas armature to the pressurized gas bottle in such a way that when pressurized gas is supplied from the pressurized gas bottle to the extinguishing medium container, pressurized gas is also introduced via the mixing armature into the extinguishing agent supply line. Otherwise, the known foam extinguisher consists as usual of a pressure-resistant extinguishing agent container for containing water with an added foaming agent and the pressurized gas bottle as already mentioned coupled to the extinguishing agent container. 
         [0004]    With the foam fire extinguisher mentioned above as well as other conventional extinguishers using liquid extinguishing agents operable, with water or foam the way the extinguishing agent is discharged and, as a result, the operation of the extinguisher is predetermined in that water and extinguishing medium are both disposed in the extinguishing medium container. The use of this extinguisher is therefore limited in that the consistency of the extinguishing foam is fixed and cannot be changed. The extinguishing gun operates with a fixed nozzle whose setting is predetermined. 
         [0005]    The known foam extinguisher is therefore not universally useable and is suitable for example for extinguishing electrical fires only in a very limited way. 
         [0006]    It is therefore the object of the present invention to provide a portable or wheeled foam fire extinguisher which is improved so that the foam consistency is adjustable depending on the needs for extinguishing particular types of fire. 
       SUMMARY OF THE INVENTION 
       [0007]    A portable or wheeled fire extinguishing apparatus which is operable by water or foam, comprising a pressure resistant extinguishing medium container, a pressurized gas bottle for pressurizing the extinguishing medium container for expelling the extinguishing medium, and an extinguishing medium gun which is connected to the extinguishing medium container by a pressure resistant hose, wherein a mixing armature is installed in the extinguishing medium line between the extinguishing medium container and the extinguishing medium gun and a pressurized gas line is connected to the admixing armature via which, during expulsion of the extinguishing medium from the extinguishing medium container, additional pressurized gas can be introduced into the extinguishing medium supplied to the extinguishing medium gun and wherein the admixing armature includes a switchable admixing valve which can be manually switched by an actuating organ selectively between a closed and an open position. 
         [0008]    In the extinguishing apparatus according to claim  1 , the present invention the foam solidification can selectively be switched on or off and can be adjusted steplessly between a minimum and a maximum value. The consistency of the foam can therefore be adjusted optimally depending on the needs. If no pressurized gas is introduced into the foam which flows to the nozzle of the extinguishing medium gun, the foam is wet and compact. With the introduction of pressurized gas for foam solidification, the foam is more or less solidified depending on the rate of pressurized gas introduction and is drier, lighter and more stable. 
         [0009]    Preferably, the pressurized gas admixing valve for adjusting the foam solidification is attached to the extinguishing medium container so that only a hose extends from the extinguishing medium container, that is from the admixing valve attached to the container, to the extinguishing gun. 
         [0010]    The extinguishing gun may advantageously be provided with a switchable nozzle arrangement in order to be able to selectively provide a nozzle delivering a narrow compact droplet jet or a more or less finely atomized wider jet. To this end, in particular a pivot mechanism may be provided to permit selectively the use of a foam tube or a jet spray tube. The foam tube or jet may furthermore be provided at the upstream end thereof with air inlet openings whose opening cross-sections are controllable by an adjustment sleeve steplessly between a fully closed and a fully open position. 
         [0011]    In a further development, the fire extinguisher according to the invention includes a separate foaming medium container which can be filled and is arranged separate from the water container. The foaming medium container may be attached at a suitable place at the outside of the water container but it may also be arranged in the interior thereof. The interior of the water container as well as the interior of the foam container can be pressurized by pressurized gas from a pressurized gas bottle for displacing the water and, respectively, the foaming medium from the respective container. The discharge lines of the water container extend to a mixing valve which includes a normally adjustable valve element by which the admixture of foaming medium to the water is controllable. It is also possible to make the admixing of foaming medium to the water controllable in steps or steplessly by providing a corresponding valve element. 
         [0012]    An extinguisher according to the invention further developed in this way can then be operated as a pure water extinguisher or a foam extinguisher. During operation as a foam extinguisher, selectively the pressurized gas for the foam solidification may be admixed. The pressurized gas may be added either to the foaming medium before its admission to the water outlet line from the water container so that foaming medium provided with pressurized gas is introduced into the water outlet line. Also, foaming medium and pressurized gas may be directly admixed to the water outlet line at the same location. 
         [0013]    As a result, the fire extinguisher according to the invention has decisive advantages: 
         [0014]    If the water and the foaming medium are contained in separate containers, the filled extinguisher can be used at the site of operation depending on the conditions encountered, simply by switching over, selectively as pure water fire extinguisher or as a foam fire extinguisher. If the apparatus is to be used as a foam extinguisher, by adjustment of the foam medium- and pressurized gas admixture to the water discharged from the water container the consistency of the foam can be controlled over the whole range between heavy foam and pressurized air foam. Since furthermore the admixture rate of air is variably adjustable at the foam pipe, also the flake size and the moisture of the foam and the foaming rate can be adjusted in a wide range. 
         [0015]    Expediently, the fire extinguisher may be designed so that it can rapidly be re-filled by the user during use in that the water container includes a separate water inlet opening provided with a cover which can be opened by hand without the need for a tool and the pressurized gas bottle may be connected to the container group by way of a rapid coupling arrangement which can also be operated by hand without the need for a tool. 
         [0016]    An exemplary embodiment of the invention is shown in the accompanying drawings and described below in detail with reference to the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]      FIG. 1  is a perspective view of an embodiment of a fire extinguisher according to the invention in a state ready for use. 
           [0018]      FIG. 2  shows the fire extinguisher of  FIG. 1  in a disassembled state, 
           [0019]      FIG. 3  shows the extinguisher gun disconnected from the jet tube change-over arrangement, and 
           [0020]      FIG. 4  shows schematically in a block representation an embodiment of a fire extinguisher with separate foam medium and water containers. 
       
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
       [0021]      FIG. 1  shows in a perspective view the complete fire extinguisher including an extinguishing medium container  1 , a pressurized gas bottle  2  strapped to the container  1  and an extinguisher gun  3  which is inserted into a retaining structure connected to the extinguishing medium container  1  and in communication with the extinguishing medium container  1  via an extinguishing medium hose  4 . 
         [0022]      FIG. 2  shows the fire extinguisher of  FIG. 1  in an exploded view in order to make also the otherwise covered components visible. 
         [0023]    The extinguishing medium container  1  has a top wall  11  provided with an extinguishing medium filler nozzle  12  which projects upwardly from the top wall and via which water and foaming medium can be filled into the extinguishing medium container  1 . A closure lid  13  with a pressure relief valve which can be installed and removed by means of a hand wheel without the need for a tool serves as a closing element for closing the filler nozzle  12 . 
         [0024]    On the top wall  11  of the extinguishing medium container  1 , additional components are mounted which will be described below. They are covered by a hood  15  which can be attached to the extinguishing medium container by screws and which is provided with a handle  16 . 
         [0025]    On the outside of the extinguishing medium container  1 , a support structure  17  for holding the extinguisher gun  3  is mounted. 
         [0026]    The pressurized gas bottle  2  provided with an outlet valve that can be operated by a hand wheel  21  arranged on top and connectable by a rapid connector  22  for example in the form of a threaded coupling is mounted onto the top wall  11  of the fire extinguishing medium container  1  and is provided at its top with a manometer  51 . 
         [0027]    Furthermore, an admixing valve block  6  is mounted onto the top wall  11  of the fire extinguisher  1 . The valve block  6  includes an admixing valve for the selective admixture of pressurized gas to the extinguishing medium leaving the extinguishing medium container  1 . The valve which is disposed in the interior of the valve block  6  and which is not visible in the drawings is manually operable by an operating organ  61 . 
         [0028]    From the bottom of the extinguishing medium container  1 , an extinguishing medium outlet pipe  18  extends to the valve block  6 . Furthermore, at the upper connecting stub  62  of the valve block  6  as shown in the figure, the extinguishing medium hose  4  can be connected which extends to the extinguisher gun  3 . 
         [0029]    From the pressure reducing valve  5 , a pressurized gas line which is not visible in the drawing extends into the interior of the extinguishing medium container  1 . It extends through the top wall  11  for pressurizing the extinguishing medium contained in the extinguishing medium container  1  for the purpose of forcing the medium out of the extinguishing medium outlet pipe  18 . In addition, a pressurized gas line extends from the pressure reducing valve  5  into the valve block  6  to the admixing valve which is contained in the vale block  6  and which is switchable by the operating organ  61  between a closed and an open position. Preferably, the valve is of such a design that the opening cross-section of the pressurized gas line within the valve block is adjustable in a stepless manner between the closed and the fully open position. However, the adjustment may occur in steps. In this way, the foam solidification can be adjusted as desired that is it can be switched on and off and preferably it can be volume-controlled. 
         [0030]      FIG. 3  shows the fire extinguisher gun  3  (without the extinguishing medium hose  4 ) in a disconnected representation. The gun consists of a gun part  31  with an operating handle provided with a connector  32 , a coupling member  33  which can be coupled to the connecter  32 , a foam tube  34  and a spray jet tube  35 . The foam tube  34  and the spray jet tube  35  are both mounted to the coupling member  33 . The coupling member  33  includes a pivot part  36  which can be fixed or released by a hand wheel  37  and which makes a switchover of the respective effective tube, that is, either the foam tube  34  or the spray jet tube  35  for use with the extinguishing gun  3  possible. 
         [0031]    At its rear end, the foam tube  34  is provided with a sleeve  38  which has a plurality of openings  39  distributed over the circumference thereof. The rear end of the foam tube has openings corresponding to the openings  39  of the sleeve  38 . The sleeve  38  is rotatable over a certain angle of rotation which, as is shown in  FIG. 3 , is determined by a circumferentially extended elongated opening  38   a  and a stop screw  38   b.  The openings  39  of the sleeve  38  can be moved into a position in which the openings in the rear end of the jet tube  34  are completely covered and a position in which the openings are aligned. By rotating the sleeve  38 , the openings at the rear end of the foam tube  34  can be closed steplessly or they can be fully or partially opened to facilitate access of ambient air to the foam emitted via the foam tube for further modification of the foam consistency. Instead of the rotatable sleeve, an axially movable sleeve may be provided. 
         [0032]      FIG. 4  shows in a schematic representation a further development of the invention in which, in connection with the extinguishing medium container  1 , a separate water container  1   a  and a separate foam medium container  1   b  are provided. 
         [0033]    Since the foam medium part in the water is relatively small during foam extinguishing operation, the foam medium container  1   b  can be substantially smaller than the water container  1   a.    
         [0034]    However, it is advantageous if the foam medium container  1   b  is large enough so that it can accommodate several times the foam medium amount needed for a complete filling of the water container  1   a.  In this way, during operation of the extinguisher, only water has to be refilled when it has all been used and the extinguisher can continue to operate as a foam extinguisher after a water refill if the foam medium reserve lasts for several water refills. 
         [0035]    The foam medium container may be arranged within the water container—of course with its own filler opening or it may be mounted to the outside of the water container at any suitable location at the side, the top or bottom of the water container. 
         [0036]    The valve block  6  then includes a manually operable admixing valve  6   a  for admitting pressurized gas to the discharge line  18  extending from water container  1   a  to the valve block  6 , as well as a manually operable admixing valve  6   b  for admixing foam medium to the water in the discharge line  18 . 
         [0037]    The arrangement may be so set up that a pressurized gas line extends from the safety valve  5  directly to the foam medium container  1   b  so that, there, the foam medium is also pressurized like the water in the water container  1   a,  or the admixture valve  6   b  for the foam medium may be combined with a pressurized gas valve (not shown) which, upon switching on the foam medium addition to the extinguisher water, a pressurized gas line, which extends from the safely valve  5  via the valve block  6  to the foam medium container, is at the same time activated so that the foam medium container is pressurized only during foam extinguishing operation of the fire extinguisher. 
         [0038]    Also, the admixing valve  6   b  for admixing foam medium may be so designed, that it is movable either only between an on and an off position, but it is preferably of such a design that it permits a stepped or stepless adjustment for controlling the foam composition, that is the foam medium content in the water.