Abstract:
A multi application fire sprinkler (MAFS), including a conical element, with a shape selected from a variety of options, comprising a component of a variable orifice, and arm and spiral spring, which can be calibrated, for the purpose of granting the MAFS with qualities which enable its use in any application and in any working conditions which require a fire sprinkler.

Description:
REFERENCE TO CROSS-RELATED APPLICATION 
       [0001]    This application claims priority from U.S. Provisional Application No. 61/155,161, filed on Feb. 25, 2009, herein incorporated by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to automatic fire sprinklers, more particularly, to automatic fire sprinklers having a variable, self-adjusting orifice, and more particularly to a Multi Application Fire Sprinkler (MAFS). 
       BACKGROUND OF THE INVENTION 
       [0003]    The first automatic sprinkler patent known in the field is entitled “automatic fire extinguisher” to Henry S. Parmelee, granted: Aug. 17, 1874. 
         [0004]    Since then, many improvements have been made in fire extinguishment systems in general, and particularly in sprinklers. An elaborate explanation is provided by Prof. Ralph R. Mehr, the inventor as of the present invention, in his paper: “The Theory and Practice of Variable Orifice in Automatic Sprinkler Systems”, published in the Journal of the National Fire Sprinkler Association, MAY/JUNE2008/No. 148 pages 73-77, which is incorporated by reference for all purposes as if fully set forth herein. 
         [0005]    The term “automatic” is used here in the sense that the sprinkler is activated without human intervention when the sprinkling of water or any other extinguishment fluid is required for fires. 
         [0006]    Typically, an automatic fire sprinkler includes a body, an inlet connected to a source of pressurized water, or fire retardant fluid, a passageway between the inlet and a flow-adjusting orifice, which also serves as an outlet. 
         [0007]    Additionally, a plug closing the orifice when the sprinkler is in standby condition is held in place by a thermally sensitive element, or by another name, a heat sensitive fusible element. When the temperature is elevated to a pre-determined value, the thermally sensitive element disintegrates. Consequently, the water pressure urges the plug away from the orifice, enabling the sprinkler to discharge. A supported deflector distributes the water stream flowing from the orifice, dispersing the stream over the region to be protected by the sprinkler. 
         [0008]      FIG. 1   a  of the prior art illustrates an automatic fire fixed orifice sprinkler  101 , having a deflector  11  disposed in a predetermined distance from the sprinkler cylindrical body  13 , in an inactive standby state. 
         [0009]      FIG. 1   b  of the prior art illustrates the automatic fire sprinkler  101 , in an active state, when it is spraying and dispersing water droplets  12 . 
         [0010]    Typically, each automatic fire sprinkler  101  includes a deflector disposed to disperse the fluid emanating from a discharge orifice in a predetermined pattern. 
         [0011]      FIG. 2  of the prior art illustrates an adjustable deflector sprinkler  102  as described in U.S. Pat. No. 5,036,923, to Shea, Sr., Entitled: “Fire sprinkler with adjustable deflector”, granted: Aug. 6, 1991. 
         [0012]    The adjustable deflector sprinkler  102 , has a deflector assembly  11 , which in an inactive state of the sprinkler, is attached to a cylindrical body  13 , granting esthetical and additional practical benefits. 
         [0013]    The adjustable deflector sprinkler  102  has a cylindrical body  13  having an inlet  16  and a fixed orifice  17 . 
         [0014]    The deflector assembly  11  is attached to the cylindrical body  13  by a pair of connector struts  15 . The struts  15  accommodate movement of the deflector assembly  11 , between an inactive position shown by dashed lines in  FIG. 2  and an active position shown by solid lines therein. 
         [0015]    When there is no fire in close proximity, a eutectic sensor material (not shown) retains an actuator assembly in place. However, at a predetermined environmental temperature, the eutectic sensor material melts, allowing the deflector assembly  11  to move downward to the active position. 
         [0016]    From the initial invention of the automatic sprinkler, the orifice of the sprinkler has had a fixed value defined by the diameter and shape. This characteristic creates some limitations to the sprinkler performance, such as: 
         [0017]    Different applications (i.e. different occupancies, such as residential versus storage), require different sprinklers. 
         [0018]    In a process of fire development, more water throughput from the initial sprinklers opened would enable faster control of the fire, but flow is limited by the orifice. 
         [0019]    Each sprinkler exhibits optimal performance at limited range of pressures. 
         [0020]    Furthermore, use of sprinklers can often cause severe damage in itself, if the quantity of sprinkled water or fire retardant fluid is excessive, 
         [0021]    The various requirements of automatic fire sprinklers are defined in the National Fire Protection Association (NFPA) 13 Standard for the installation of sprinkler systems, which was also adopted by American National Standards Institute (ANSI). This standard is periodically revised. 
         [0022]    Generally, the water flow rate from a sprinkler is determined by the formula: 
         [0000]    
       
      
       Q=K√{square root over (P)} 
      
     
         [0023]    wherein:
       Q is a flow rate, (of a fluid flow through an orifice of a sprinkler);   K is the K-factor, a coefficient (dependent upon a geometry and dimensions of the sprinkler, determined by standard flow testing); and   P is a fluid pressure, (at the inlet to the sprinkler).       
 
         [0027]    Different applications require different water flows, i.e., sprinklers that have different K-factors K, and/or different inlet water pressures P. For standard coverage, the most commonly used sprinklers have a K-factor of 5.6, while extended coverage applications use sprinklers having larger K-factors of 8 to 11.2, which have correspondingly larger orifices. 
         [0028]    One advanced sprinkler is the low-pressure fast response (LPFR) sprinkler, also known as the early suppression fast response (ESFR) sprinkler Characteristically, this sprinkler has K-factors between 14 and 25.2, a short time of response, and high water flow rates. 
         [0029]    Typical prior art examples of these LPFR or ESFR sprinklers are U.S. Pat. No. 5,829,532, and U.S. Pat. No. 6,502,643, both entitled “Low pressure, early suppression fast response sprinklers”, both to Meyer, et al., U.S. Pat. No. 6,059,044 to Fischer, entitled “Fire protection sprinkler and deflector”, and U.S. Pat. No. 6,336,509 to Polan, et al., entitled “Low pressure fast response bulb sprinklers”. 
         [0030]    The use of sprinklers having greater K-factors reduces the required water pressure at the inlet, and therefore obviates the need of installing more robust and capital-intensive systems. 
         [0031]    In addition, a lower water pressure results in larger droplets being produced by the deflector. The larger droplets have a higher momentum that assists them in being deflected further from the sprinkler, thereby extending the coverage area. 
         [0032]    Alternatively, for a given water pressure, the use of sprinklers having larger orifices increases the flow of water through each sprinkler, thus reducing the required number of sprinklers for the requisite coverage area. 
         [0033]    In prior art sprinkler systems, after a fire starts, the thermally sensitive element of the closest sprinkler disintegrates at the pre-determined temperature, permitting Q 1  of water to discharge at inlet pressure P 1 . If the fire has not been extinguished by this sprinkler, additional heat is generated and spreads, and a second sprinkler discharges. As a result, Q 1  and P 1  of the first sprinkler decrease to Q 2  and P 2 , since now the same water source is feeding two sprinklers. As additional sprinklers discharge, the values of Q and P of the first and second sprinklers further decrease. Final Q and P values are reached only when no additional sprinklers discharge. 
         [0034]    In a constant value K-factor sprinklers the inlet pressure P changes according to the number of discharging sprinklers, the amount of water discharged by the first sprinkler, according to the above mentioned formula, is 
         [0000]        Q   1   =K √{square root over ( P   1 )}  Q   2   =K √{square root over ( P   2 )} etc. 
         [0035]    Consequently, in the first stage of the operational pattern, the amounts Q 1  and Q 2  are greater than the amount discharged by the first-opened sprinkler when more sprinklers are in operation. 
         [0036]    In order to improve sprinkler efficiency, and broaden the range of operation, an automatic fire sprinkle was invented by Prof. Ralph R. Mehr, the inventor of the present invention, which is described in U.S. Pat. No. 7,237,619 entitled “Automatic Fire Sprinkler Having a Variable Orifice”, Filed: Jul. 23, 2003, granted: Jul. 3, 2007, which is incorporated by reference for all purposes as if fully set forth herein. 
         [0037]    The variable orifice of the variable orifice sprinkler ( 103 ), is responsive to the water inlet pressure of the sprinkler. 
         [0038]      FIG. 3   a  of the prior is a longitudinal cross sectional view, schematic drawing of a variable orifice sprinkler  103 , in a non-flowing condition, the sprinkler having a variable orifice ( 18 ) which is adjusted by an inner conical element  20 . 
         [0039]    Variable orifice sprinkler  103  has a cylindrical body  13  with a threaded connection  14  attached to the water piping system (not shown in the drawing), a deflector assembly  11  tightly closing the cylindrical body  13  in a non-flowing position, thereby preventing water flow through a variable orifice ( 18 ) (shown open in  FIG. 3   b ). Two arms  21  allow free longitudinal movement of the deflector assembly  11 , so as to increase and decrease the distance between the deflector assembly  11  and an end side of the cylindrical body  13 , and spiral springs  22  are bound around the arms  21 . 
         [0040]    A conical element  20  is associated with the deflector assembly  11 . In a non-flowing position the conical element  20  completely penetrates into the cylindrical body  13 , closing the variable orifice  18 . 
         [0041]    Preferably, arms  21  and springs  22  are protected from external dirt and physical damages by an external box  25 . 
         [0042]      FIG. 3   b  of the prior is a longitudinal cross sectional view, schematic drawing of the variable orifice sprinkler  103 , in a flowing condition. 
         [0043]    The water or other fire retardant fluid is pressurized into the cylindrical body  13  through inlet  16 , and as long as the variable orifice  18  is blocked, there is no flow through the variable orifice sprinkler  103 . 
         [0044]    When a fire starts, and heat evolves from the burning materials, the fusible element ( 19 ) fuses, deflector assembly  11  is urged out by the pressure, opening a gap between deflector assembly  11  and cylindrical body  13 , and most of conical element  20  is moved out of cylindrical body  13 , such that variable orifice  18  is practically at its maximum possible opening. Arms  21  are now at their extreme position outside box  25 , and springs  22  are in their most restricted position 
         [0045]    As the pressure of the water flowing through the variable orifice  18  is decreased, springs  22  urge the deflector assembly  11  towards the cylindrical body  13 . The cross-sectional area of the penetrating section of conical element  20  increases with decreasing pressure, thereby reducing the cross-sectional area of the water flow-path and further restricting the flow of water discharged by the variable orifice sprinkler  103 . 
         [0046]    None of the prior art overcomes the limitations specified above. It would be highly advantageous to have an improved automatic fire sprinkler system that optimizes the quantity of water or fire retardant fluid sprayed during fire, to decrease the size of the core fire and the time required for extinguishment. 
         [0047]    It would be of further advantage if such a sprinkler of such a system had such qualities that would enable its calibration to be adaptable to the place where it is installed, such as a residential home or a storage warehouse containing goods including flammable materials. 
       SUMMARY OF THE INVENTION 
       [0048]    According to the teaching of the present invention there is provided an automatic multi application fire sprinkler having a variable orifice, which is adaptable for efficient work in a wide range of flow pressures, and can be calibrated for a wide range of fire purposes, thus sparing the need for automatic fire sprinklers with different characteristics. 
         [0049]    Standard automatic fire sprinklers are inefficient and can cause severe water damage when they are not specifically suited for working purpose and conditions. The automatic multi application fire sprinkler enables use of a single type of automatic fire sprinkler, by means of a mechanical structure which controls the supply of water flowing through it during its activation, for efficient performance even under different work pressures. Furthermore, its performance can be well adapted by providing the option for calibration of element parameters and replacing elements. 
         [0050]    According to the present invention there is provided a multi application fire sprinkler including: (a) a cylindrical body, having an inlet at one end and a variable orifice at a second end of the cylindrical body, and a cylindrical body disc; (b) at least one arm, wherein the arm is mounted through a cylindrical body disc hole; (c) at least one spiral spring disposed around the at least one arm; (d) a deflector assembly disposed on the at least one arm; (e) a movement limiter mechanism disposed on the at least one arm, wherein the at least one spiral spring is located between the cylindrical body disc and the movement limiter mechanism; and (f) a conical element disposed on the deflector assembly, wherein the combination of the conical element, the at least one arm, and the at least one spiral spring determines a water flow rate through the variable orifice according to water pressure. 
         [0051]    According to a further feature of the described embodiments the conical element is a linear conical element. 
         [0052]    According to further features in the described embodiments the conical element is a narrow conical element. 
         [0053]    According to further features in the described embodiments the conical element is a wide conical element. 
         [0054]    According to a further feature of the described embodiments the conical element can be selected from a group consisting of a linear conical element, a wide conical element, and a narrow conical element, and wherein the combination of the conical element, the at least one arm, and the at least one spiral spring determines a water flow rate through the variable orifice according to water pressure. 
         [0055]    According to another further feature of the described embodiments, in an inactive state of the multi application fire sprinkler the at least one spiral spring is practically at its natural length, which practically equals a possible movement length of the deflector assembly up to its full compression, wherein one end of the at least one spiral spring is in touch with the cylindrical body disc, and wherein a second end of the at least one spiral spring is in touch with the movement limiter mechanism. 
         [0056]    According to still another further feature of the described embodiments in an inactive state of the multi application fire sprinkler the at least one spiral spring is compressed relative to its natural state, wherein a possible movement range of the deflector assembly is shorter than a length of the at least one spiral springs natural length, wherein one end of the at least one spiral spring is in touch with the cylindrical body disc, and wherein a second end of the at least one spiral spring is in touch with the movement limiter mechanism. 
         [0057]    According to still another further feature of the described embodiments, in an inactive state of the multi application fire sprinkler the at least one spiral spring is practically at its natural length, wherein the natural length is shorter than a possible movement range of the deflector assembly to a full compression length of the at least one spiral spring. 
         [0058]    According to still another further feature of the described embodiments, a position of an element of the movement limiter mechanism on the at least one arm can be manually adjusted for adaptation to desired functions and working conditions of the multi application fire sprinkler. 
         [0059]    According to still another feature of the described embodiments the element of the movement limiter mechanism is a nut. 
         [0060]    According to still another feature of the described embodiments the multi application fire sprinkler is configured such that the at least one spiral spring can be manually replaced easily, with an alternative spiral spring. 
         [0061]    According to still another features in the described embodiments the linear conical element has a cross section diameter, perpendicular to a symmetry axis of the linear conical element, which equals the mathematical product of A and a constant c sub 2, wherein A equals a constant c sub 1 minus h, wherein h is a distance measured from the cone base, towards a cone vertex of the linear conical element. 
         [0062]    According to still another feature of in the described embodiments the constant c sub 1 practically equals 2.0, and wherein the constant c sub 2 practically equals 0.5245. 
         [0063]    According to still another feature of the described embodiments the narrow conical element has a cross section diameter, perpendicular to a symmetry axis of the narrow conical element, which equals the mathematical product of D to the power of n3 and a constant c sub 6, wherein D equals a constant c sub 5 minus h, wherein h is a distance, measured from the cone base, towards a cone vertex of the narrow conical element. 
         [0064]    According to still another feature of the described embodiments the n3 practically equals 2.0, wherein the constant c sub 5 practically equals 2.0, and wherein the constant c sub 6 practically equals 0.262. 
         [0065]    According to still another feature of the described embodiments the wide conical element has a cross section diameter, perpendicular to a symmetry axis of the wide conical element equals B to the power of n2, wherein B equals a constant c sub 3 minus C, wherein C equals the mathematical product of h to the power of n1 and a constant c sub 4, wherein h is a distance, measured from the cone base, towards a cone vertex of the wide conical element. 
         [0066]    According to still another feature of the described embodiments the n1 practically equals 0.5, wherein the n2 is practically equals 0.5, wherein the constant c sub 3 practically equals 1.1, and wherein the constant c sub 4 practically equals 0.778. 
         [0067]    Additional objects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0068]    The invention is herein described, by way of example only, with reference to the accompanying drawings, wherein: 
           [0069]      FIG. 1   a  of the prior art illustrates an automatic fire fixed orifice sprinkler, having a deflector disposed to in a predetermined distance from the sprinkler body, in an inactive or standby state. 
           [0070]      FIG. 1   b  of the prior art illustrates the automatic fire sprinkler, in an active state, when it is spraying and dispersing water droplets. 
           [0071]      FIG. 2  of the prior art illustrates the adjustable deflector sprinkler of Shea. 
           [0072]      FIG. 3   a  of the prior art is a longitudinal cross sectional view, schematic drawing of a variable orifice sprinkler, in a non-flowing condition, the sprinkler having a variable orifice adjusted by an inner conical element. 
           [0073]      FIG. 3   b  of the prior art is a longitudinal cross sectional view, schematic drawing of a variable orifice sprinkler, in a flowing condition. 
           [0074]      FIG. 4   a  is a side view schematic illustration of an illustrative, exemplary embodiment of a multi application fire sprinkler, according to the present invention, upon which section plane a-a is marked. 
           [0075]      FIG. 4   b  is an isometric schematic illustration of an illustrative, exemplary embodiment of a multi application fire sprinkler, according to the present invention, upon which section plane b-b is marked. 
           [0076]      FIGS. 5   a ,  5   b , and  5   c  are a-a schematic longitudinal cross sectional views illustration of an illustrative, exemplary embodiment of the multi application fire sprinkler (MAFS), according to the present invention, wherein in the inactive state spiral springs are in their natural length, which practically equals the length of possible movement of the deflector assembly up to their full compression. 
           [0077]      FIGS. 6   a ,  6   b , and  6   c  are a-a schematic longitudinal cross sectional views illustration of an illustrative, exemplary embodiment of the MAFS, according to the present invention, wherein in the inactive state, the spiral springs compressed to a length shorter than their natural length. 
           [0078]      FIGS. 7   a ,  7   b , and  7   c  are a-a schematic longitudinal cross sectional views illustration of an illustrative, exemplary embodiment of the MAFS, according to the present invention, wherein in the inactive state, the spiral springs are at their natural length with no load, which is shorter than the range of possible movement of the deflector assembly up to their full compression. 
           [0079]      FIGS. 8   a ,  8   b , and  8   c , are a-a schematic longitudinal partial cross sectional views illustration of an illustrative, exemplary embodiment of the multi application fire sprinkler (MAFS), according to the present invention, showing three conical elements, each with a different spatial shape. 
           [0080]      FIG. 9  is a graph which compares the water flow rate as a function of the pressure of the MAFS according to the present invention, equipped with a narrow conical element, with the water flow rate of two prior art fire sprinklers. 
           [0081]      FIG. 10  is a side views illustration of an illustrative, exemplary embodiment of arm, spiral spring, and deflector assembly of the MAFS, according to the present invention, in three different states. 
           [0082]      FIG. 11  is a b-b schematic lateral partial cross sectional view illustration of an illustrative, exemplary embodiment of the multi application fire sprinkler (MAFS), according to the present invention. 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0083]    The present invention is of a multi application fire sprinkler (MAFS)  200 . The principles and operation of a MAFS according to the present invention may be better understood with reference to the drawings and the accompanying description. 
         [0084]    Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. 
         [0085]    Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The materials, dimensions, methods, and examples provided herein are illustrative only and are not intended to be limiting. 
         [0086]    The following list is a legend of the numbering of the application illustrations:
         11  deflector assembly     12  water droplets     13  cylindrical body     13   a  cylindrical body disc     13   b  cylindrical body disc hole     14  threaded connection     15  struts     16  inlet     17  fixed orifice     18  variable orifice     19  fusible element     20  conical element     20   l  linear conical element     20   w  wide conical element     20   n  narrow conical element     21  arm     22  spiral spring     23  arm screw     24  nut     25  external box     26  movement limiter mechanism     101  automatic fire fixed orifice sprinkler, (prior art)     102  adjustable deflector sprinkler, (prior art)     103  variable orifice sprinkler, (prior art)     200  multi application fire sprinkler (MAFS)       
 
         [0112]    Referring now to the drawings,  FIG. 4   a  is a side view schematic illustration of an illustrative, exemplary embodiment of a multi application fire sprinkler (MAFS)  200 , according to the present invention, upon which section plane a-a is marked. The MAFS  200  is shown in the present illustration in an active state. 
         [0113]      FIG. 4   b  is an isometric schematic illustration of an illustrative, exemplary embodiment of a multi application fire sprinkler  200 , according to the present invention, upon which section plane b-b is marked. The MAFS  200  is shown in the present illustration in an active state. 
         [0114]    The MAFS  200  adapts itself for more efficient work in a wide range of working pressures and enables calibration for a wide variety of fire extinguishment system requirements, thus sparing the need for different types of automatic fire sprinklers with different characteristics. 
         [0115]    MAFS  200  enables use of a single type of automatic fire sprinkler by means of a mechanical structure which controls the supply of water flowing through it during its activation, for efficient performance even in the case of changes in working pressure. In addition, its working performance can be significantly improved by enabling the calibration of element parameters and even replacing elements. 
         [0116]    Some of the advantages of the MAFS are:
       The first MAFS, as opposed to prior art fire sprinklers, provides a maximal quantity of water over the core of the fire, while the total quantity of water sprayed does not exceed standard allotment.   Less fire sprinklers are required for fire extinguishment, and therefore there is less fire and water damage to property.   The MAFS is suitable for all classifications of occupancies and commodities, such as light, ordinary, extra and special hazard occupancies, and commodities.       
 
         [0120]      FIGS. 5   a ,  5   b , and  5   c  are a-a schematic longitudinal cross sectional view illustrations of an illustrative, exemplary embodiment of the multi application fire sprinkler (MAFS)  200 , according to the present invention, wherein in the inactive state, which is also maintained when the MAFS is engaged in a fire system and is in standby state, the spiral springs  22  are at their natural length without any load, which practically equals the possible movement length of the deflector assembly  11  up to their full compression. 
         [0121]    The mechanical structure of MAFS  200  resembles the structure of the variable orifice sprinkler  103  described above, however includes differences which grant it preferable characteristics. These differences will be described in the following. 
         [0122]    MAFS  200  has a variable orifice  18  adjusted by an inner conical element  20 , which can have various spatial shapes. 
         [0123]    MAFS  200  has a cylindrical body  13  with a threaded connection  14  and can be connected to a water piping system (not shown in the drawing), a deflector assembly  11  tightly closing the cylindrical body  13  in a non-flowing position, in standby or inactive state, thereby preventing water flow through the variable orifice  18 . The illustration shows two arms  21  that allow longitudinal movement of deflector assembly  11 , so as to increase and decrease the distance between the deflector assembly  11  and cylindrical body disc  13   a , and two spiral springs  22  bound around arms  21 . The maximum possible length between the deflector assembly  11  and the cylindrical body disc  13   a  is marked in the illustration as l 5 . 
         [0124]    The cylindrical body disc  13   a  has, in the case shown in the present illustration, two cylindrical body disc holes ( 13   b ), which are suitable to allow through movement of the arms  21  (as will be shown in  FIG. 11 ). 
         [0125]    Although the present illustration shows two arms  21 , and two spiral springs  22 , the present invention is not limited to use of these specific numbers. Likewise, the two arms  21  are practically identical to each other, and the two spiral springs  22  are also identical to each other. 
         [0126]    The conical element  20  is associated with the deflector assembly  11 . In a non-flowing position the conical element  20  completely penetrates into the cylindrical body  13 , closing the variable orifice  18  so as to prevent passage of water in any state of water pressure that may be applied on MAFS  200 . 
         [0127]    Preferably, arms  21  and springs  22  are protected from external dirt and physical damages by an external box  25 . 
         [0128]    A non-flowing position is shown in  FIG. 5   a . The water or other flame retardant fluid is pressurized into the cylindrical body  13  through inlet  16  while the variable orifice ( 18 ) is blocked, thus there is no flow through the MAFS  200 . 
         [0129]    A start position is shown in  FIG. 5   b . When a fire starts, and heat evolves from the burning materials, fusible element ( 19 ) fuses. So, a force resulting from the pressure of water is applied upon the deflector assembly  11  and upon the conical element  20  with the purpose of opening the passage for the flow of water, while a counterforce is applied by the springs with the purpose of closing the passage for the flow of water. The effect of gravity is usually negligibly small with regard to the effects of the other forces described above. 
         [0130]    A fully open position is shown in  FIG. 5   c . When the water pressure applies sufficient force, which overpowers the force applied by the springs, the passage is opened by the lowering of the deflector assembly  11  to the end of its range of movement, namely to length l 5  which is limited by the mechanical structure and will be described in more detail in the following ( FIG. 9 ). 
         [0131]    Arms  21  are now at their extreme position outside box  25 , and springs  22  are in their most restricted position. 
         [0132]    As the pressure of the water flowing through the variable orifice  18  is decreased, springs  22  urge the deflector assembly  11  towards the cylindrical body  13 . The cross-sectional area of the penetrating section of conical element  20  increases with decreasing pressure, thereby reducing the cross-sectional area of the water flow-path and further restricting the flow of water discharged by the MAFS  200 . 
         [0133]    Whenever one multi application fire sprinkler  200  is not sufficient for the fire, more heat is evolved and multi application fire sprinklers  200  are temperature-activated. Consequently, the water pressure in the system decreases and spiral spring  22  pull back a part of arms  21 , thus decreasing the gap between the deflector assembly  11  and the cylindrical body  13 , part of conical element  20  penetrates into the cylindrical body  13 , decreasing variable orifice  18  and the amount of water flowing through the MAFS  200 . If additional MAFS  200  are activated, the process continues and the cross-sectional area of the variable orifice  18  further decreases. 
         [0134]      FIGS. 6   a ,  6   b , and  6   c  are a-a schematic longitudinal cross sectional view illustrations of an illustrative, exemplary embodiment of the multi application fire sprinkler (MAFS)  200 , according to the present invention, wherein in the inactive state, the spiral springs  22  are compressed relative to their natural state. In this case the possible movement range of the deflector assembly  11  is shorter than when the spiral springs  22  are at their natural length in the inactive state. 
         [0135]    A non-flowing position is shown in  FIG. 6   a . The water or other flame retardant fluid is pressurized into the cylindrical body  13  through inlet  16 , and as long as the variable orifice ( 18 ) is blocked, there is no flow through the MAFS  200 . 
         [0136]    A start position is shown in  FIG. 6   b . When a fire starts, and heat evolves from the burning materials, fusible element ( 19 ) fuses. This allows force to be applied by the water pressure upon the deflector assembly  11  and upon the conical element  20  with the purpose of opening the passage for the flow of water, while the springs apply a counterforce with the purpose of closing the passage for the flow of water. 
         [0137]    A full open position is shown in  FIG. 6   c . When the water pressure applies sufficient force, which overpowers the force of the springs, the passage is opened by the lowering of the deflector assembly  11  to the end of its movement range, namely to length l 6 , which is limited by the mechanical structure, and will be detailed in the following ( FIG. 10 ). 
         [0138]      FIGS. 7   a ,  7   b , and  7   c  are a-a schematic longitudinal cross sectional view illustrations of an illustrative, exemplary embodiment of the multi application fire sprinkler (MAFS)  200 , according to the present invention, wherein in the inactive state the spiral springs  22  are at their natural length without any load, with this length being shorter than the possible movement range of the deflector assembly  11  to their full compression. 
         [0139]    A non-flowing position is shown in  FIG. 7   a . The water or other flame retardant fluid is pressurized into the cylindrical body  13  through inlet  16 , and as long as the variable orifice  18  is blocked, there is no flow through the MAFS  200 . 
         [0140]    A start position is shown in  FIG. 7   b . When a fire starts, and heat evolves from the burning materials, fusible element ( 19 ) fuses, and in the state shown, which is suitable for a hanging MAFS  200 , the deflector assembly  11  drops until it meets the spiral springs  22 . Thus the water pressure applies force upon the deflector assembly  11  with the purpose of increasing the opening for passage of water, while the springs apply a counterforce with the purpose of closing the passage for water. 
         [0141]    A fully open position is shown in  FIG. 7   c . When the water pressure generates sufficient force to overpower the force of the springs, the deflector assembly  11  moves to the end of its possible movement range, namely to length i 7 , which is limited by the mechanical structure and will be described in more detail in the following ( FIG. 9 ). 
         [0142]      FIGS. 8   a ,  8   b , and  8   c , are a-a schematic longitudinal partial cross sectional view illustrations of an illustrative, exemplary embodiment of the multi application fire sprinkler (MAFS)  200 , according to the present invention, showing three conical elements  20 , each with a different spatial shape. Each conical element  20  has height H and base diameter D, whose values are in the three examples shown in the present illustrations: H=2 inch and D=1.049 inch (D is identical to the internal diameter of the cylindrical body ( 13 ), in the segment between the inlet ( 16 ) and the variable orifice ( 18 ), (which is the standard diameter of a nominal 1 inch SCH 40 steel pipe). 
         [0143]    A linear conical element  20   l  is shown in  FIG. 8   a , and its formula is: 
         [0000]        d =(2 −h )×0.5245, 
         [0000]    when h is measured from the base of the cone to its vertex. 
         [0144]    A wide conical element  20   w  is shown in  FIG. 8   b , and its formula is: 
         [0000]        d =(1.1−0.778 ×h   1/2 ) 1/2 . 
         [0145]    A narrow conical element  20   n  is shown in  FIG. 8   c , and its formula is: 
         [0000]        d =(2 −h ) 2 ×0.262. 
         [0146]    Note that these three examples of conical elements are not the only possible options of shape and dimension and do not limit the present invention in any way. 
         [0147]    The formulas can be more generalized as follows: 
         [0148]    A linear conical element formula is: 
         [0000]        d=A×c   2 =( c   1   −h )× c   2 , 
         [0000]    when h is measured from the base of the cone to its vertex. 
         [0149]    A wide conical element formula is: 
         [0000]        d=B   n2 =( c   3   −C ) n2 =( c   3   −c   4   ×h   n1 ) n2 . 
         [0150]    A narrow conical element formula is: 
         [0000]        d=D   n3   ×c   6 =( c   5   −h ) n3   ×c   6 . 
         [0151]    The performance of the MAFS in any specific configuration and any specific calibration conditions can be determined through experimentation, thus standardization institutes can determine rigid standards for adaptation of each MAFS for its designation. 
         [0152]    The structure and qualities of the MAFS enable it to work efficiently also outside of the range of pressures currently defined as the standard, which is 7-175 psi, and even at the maximal water pressure that practical water piping can provide. 
         [0153]    Each type of conical element has a unique corresponding function ƒ, with the general form of the supply equation as a function of pressure being: 
         [0000]        Q =ƒ( P ) 
         [0154]    When ƒ can be found through experimentation. 
         [0155]    Table 1 shows numerical figures enabling comparison of the water flow rate as a function of the pressure of the MAFS to the present invention, equipped with a narrow conical element  20 , with the water flow rate of two prior art fire sprinklers, one of which is suitable for Ordinary Hazard occupancies and the other of which is suitable for Extra Hazard occupancies. 
         [0156]    This data is of a specific case of calibration of the MAFS and its performance can be adapted to other specific conditions. 
         [0000]    
       
         
               
               
             
               
               
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                   
                 TABLE 1 
               
             
             
               
                   
                   
               
               
                   
                 Prior Art Fire Sprinkler 
               
               
                   
                 Hazard Occupancies 
               
             
          
           
               
                 MAFS 
                 Ordinary 
                 Extra 
               
             
          
           
               
                 h [in] 
                 d [in] 
                 P [psi] 
                 Q [gpm] 
                 Q [gpm] 
                 Q [gpm] 
               
               
                   
               
             
          
           
               
                 2.0 
                 0.000 
                 200 
                 441 
                 113 
                 158 
               
               
                 1.9 
                 0.003 
                 190 
                 430 
                 110 
                 154 
               
               
                 1.8 
                 0.010 
                 180 
                 418 
                 107 
                 150 
               
               
                 1.7 
                 0.024 
                 170 
                 407 
                 104 
                 146 
               
               
                 1.6 
                 0.042 
                 160 
                 394 
                 101 
                 142 
               
               
                 1.5 
                 0.066 
                 150 
                 381 
                 98 
                 137 
               
               
                 1.4 
                 0.094 
                 140 
                 366 
                 95 
                 133 
               
               
                 1.3 
                 0.129 
                 130 
                 350 
                 91 
                 128 
               
               
                 1.2 
                 0.168 
                 120 
                 333 
                 88 
                 123 
               
               
                 1.1 
                 0.212 
                 110 
                 314 
                 84 
                 117 
               
               
                 1.0 
                 0.262 
                 100 
                 292 
                 80 
                 112 
               
               
                 0.9 
                 0.317 
                 90 
                 269 
                 76 
                 106 
               
               
                 0.8 
                 0.378 
                 80 
                 243 
                 72 
                 100 
               
               
                 0.7 
                 0.443 
                 70 
                 214 
                 67 
                 94 
               
               
                 0.6 
                 0.514 
                 60 
                 184 
                 62 
                 87 
               
               
                 0.5 
                 0.590 
                 50 
                 151 
                 57 
                 79 
               
               
                 0.4 
                 0.671 
                 40 
                 116 
                 51 
                 71 
               
               
                 0.3 
                 0.758 
                 30 
                 82 
                 44 
                 61 
               
               
                 0.2 
                 0.850 
                 20 
                 48 
                 36 
                 50 
               
               
                 0.1 
                 0.947 
                 10 
                 18 
                 25 
                 35 
               
               
                 0.0 
                 1.049 
                 0 
                 0 
                 0 
                 0 
               
               
                   
               
             
          
         
       
     
       Performance Comparison 
       [0157]      FIG. 9  is a graph describing the water flow rate as a function of the pressure of the MAFS according to the present invention, equipped with a narrow conical element ( 20 ), and the water flow rate of two prior art fire sprinklers, one of which is suitable for Ordinary Hazard occupancies, and the other of which is suitable for Extra Hazard occupancies, according to the details of Table 1. 
         [0158]      FIG. 10  is a side view illustration of an illustrative, exemplary embodiment of arm  21 , spiral spring  22 , and deflector assembly  11  of the MAFS  200 , according to the present invention, in three different states. This illustration demonstrates the movement limitations of the deflector assembly ( 11 ). On the upper part of arm  21  is a movement limiter mechanism  26 . This mechanism can be easily adjusted for adaptation to desired functions and working conditions. In the present illustration, the mechanism includes arm screw  23  and nut  24 . The left side of the illustration shows movement limiter mechanism  26  in a state in which nut  24  is at a distance from the cylindrical body  13   a  (the cylindrical body horizontal part) whose size y max  is larger than the natural size y n , namely the unloaded size, of spiral spring  22 . This state is suitable for the position described in  FIG. 7   a.    
         [0159]    The center of the illustration shows a state in which nut  24  is at a distance y from the cylindrical body  13   a , and so it presses toward it and compresses it. This state is suitable for the non-flowing position shown in  FIG. 6   a  and for intermediary states, with regard to the movement of deflector assembly ( 11 ). 
         [0160]    The right side of the illustration shows a state in which the movement limiter mechanism  26  limits the downward movement of the arm  21  and thus also the movement of the deflector assembly ( 11 ). This limitation occurs when nut  24  is at a distance of y min  from the cylindrical body  13   a , when it equals the length of the fully compressed spiral spring  22 , namely it equals the product of the number of its coils by the width of its wire u. 
         [0161]      FIG. 11  is a b-b schematic lateral partial cross sectional view illustration of an illustrative, exemplary embodiment of the multi application fire sprinkler (MAFS)  200 , according to the present invention. The illustration shows area A of the variable orifice  18  through which there can be flow. This area is between section areas of the cylindrical body  13 , whose diameter is D, and the conical element  20 , whose variable diameter is d. 
         [0162]    Cylindrical body disc  13   a  has, in the case shown in the present illustration, two cylindrical body disc holes  13   b , which enable through movement of the arms ( 21 ). 
         [0163]    While the invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications and other applications of the invention may be made. 
         [0164]    While the invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications and other applications of the invention may be made, and in particular the present invention does not limit use of the MAFS for any specific range of water pressures, any specific hanging orientation, vertical or other, any specific type of deflector assembly, or any specific type of activation mechanism such as ordinary or fast response.