Abstract:
A portable fire extinguishing apparatus, which comprises a casing ( 20 ) and a cartridge ( 3 ) arranged inside the casing ( 20 ). The top end of the cartridge ( 3 ) is fixedly connected with the casing ( 20 ) through a snap ring ( 24 ); the bottom of the cartridge ( 3 ) is fixedly connected with the casing ( 20 ) through some nuts and bolts; and an explosion venting unit ( 2 ) is arranged at the jet end of the cartridge ( 3 ). Kinetic energy generated from explosion is consumed through shifting and limiting processes of the explosion venting units ( 2 ), therefore recoil force or forward impact force generated after explosion of explosives can be consumed or released, so that safe and effective explosion venting is achieved and hurt to human bodies or articles after explosion of grains is avoided.

Description:
TECHNICAL FIELD OF THE INVENTION 
     The invention belongs to the field of fire prevention technology, and particularly relating to a portable fire extinguishing apparatus. 
     BACKGROUND OF THE INVENTION 
     At present, existing portable fire extinguishing apparatuses are generally divided into pressure-storage dry powder fire extinguishing apparatuses and handheld aerosol fire extinguishing apparatuses, wherein a pressure-storage dry powder fire extinguishing apparatus mainly have the following disadvantages: firstly, the pressure-storage dry powder fire extinguishing apparatus causes serious pollution to the environment and serious damage to materials; secondly, the pressure-storage dry powder fire extinguishing apparatus, which needs to store high pressure gases, is large in volume and heavy in weight; thirdly, the pressure-storage dry powder fire extinguishing apparatus, which is a high pressure container, has potential safety hazards and is more dangerous in a high temperature environment of a fire; fourthly, the pressure-storage dry powder fire extinguishing apparatus, which needs to go through regular surveillance tests and inspections, is high in routine maintenance costs etc. By contrast, a portable aerosol fire extinguishing apparatus has obvious advantages and mainly comprises: a cartridge, a cartridge cover arranged on the cartridge, and a pyrotechnic composition, an ignition head, a coolant and a ceramic chip etc. arranged in the cartridge in turn and coated by a heat insulation material. Normally, after the pyrotechnic composition is ignited by the ignition head, a great deal of aerosol smog will be generated by the cartridge through rapid stratified combustion, and after being cooled by a coolant layer, these high temperature aerosols will be ejected from the cartridge cover of the cartridge to act on a fire source directly, thus extinguishing the fire. However, there are also some disadvantages. A coating defect, a pyrotechnic composition crack or a serious blockage of a gas channel may lead to a sudden rise of the pressure in the cartridge to deflagrate the cartridge. As a result, a high pressure gas will thrust the cartridge cover of the cartridge forwards and will be vented rapidly to cast the cartridge cover of the cartridge and other substances in the cartridge forwards at an extremely high speed, thus causing a very large recoil force. The powerful recoil force drives the cartridge cover to move backwards rapidly, which is easy to cause an injury to an operator. At the same time, after explosion venting, the cartridge cover of the inner cartridge of the extinguishing apparatus will also break away from the cartridge and fly outwards for a relatively long distance, which may cause other accidents. In addition, the cartridge of the extinguishing apparatus is easily loosened in a casing and the problem of fixation of the cartridge is a subject to be solved. 
     SUMMARY OF THE INVENTION 
     To solve disadvantages existing in a portable fire extinguishing apparatus in the prior art, the invention provides a portable fire extinguishing apparatus provided with an explosion prevention facility and capable of effectively preventing explosion, releasing pressure and reducing a recoil force after deflagration. 
     The technical solution applied by the invention to solve the technical problem above is: 
     a portable fire extinguishing apparatus, comprising: a casing ( 20 ) and a cartridge ( 3 ) arranged inside the casing ( 20 ), wherein the top end of the cartridge ( 3 ) is fixedly connected with the casing ( 20 ) through a snap ring ( 24 ); the bottom of the cartridge ( 3 ) is fixedly connected with the casing ( 20 ) through nuts and bolts, thus facilitating installation on one hand, and the cartridge is well secured in the casing at two sides so that the cartridge is not easily rotated or loosened on the other hand. 
     An explosion venting device ( 2 ) is further arranged at the jet end of the cartridge ( 3 ) of the fire extinguishing apparatus of the invention to effectively prevent explosion and release pressure, reduce a recoil force acting on the cartridge ( 3 ) after deflagration and prevent a cartridge cover ( 4 ) of the cartridge ( 3 ) from flying outwards; the explosion venting device ( 2 ) mainly comprises a frictional layer ( 11 ), a connection rod ( 12 ), a connection rod guiding unit ( 13 ) and a connection rod limiting device ( 14 ), wherein the connection rod ( 12 ) is connected with the cartridge cover ( 4 ) of the cartridge ( 3 ); the frictional layer ( 11 ) is arranged between the connection rod ( 12 ) and an outer wall of the cartridge ( 3 ); the frictional layer ( 11 ) provides a frictional resistance and a buffering force for the connection rod ( 12 ) when the same is guided by the connection rod guiding unit ( 13 ) to displace along a direction towards which a hot air stream of the cartridge ( 3 ) is ejected; the connection rod guiding unit ( 13 ) is a device capable of providing a guiding function for the connection rod ( 12 ) when the same is moving; the connection rod limiting device ( 14 ) is a device capable of limiting the connection rod ( 12 ) when an extremity of the same reaches an spout of the cartridge ( 3 ). Powerful kinetic energy generated after deflagration of a grain is converted into deformation energy and overcoming resistance etc. through frictional acting and energy conversion and is dispersed or consumed, thus effectively releasing the pressure and reducing the recoil force. 
     The connection rod guiding unit ( 13 ) may be a guiding ring ( 15 ) fixedly connected with the connection rod ( 12 ) or a guiding groove provided on the outer wall of the cartridge ( 3 ) and capable of enabling the connection rod ( 12 ) to slide axially along the guiding groove; at the same time, the connection rod limiting device ( 14 ) comprises a flanging ( 16 ) fixedly connected with the jet end of the cartridge ( 3 ) and a clamping claw ( 17 ) for fixing the connection rod ( 12 ); in addition, an elastic body ( 18 ) may be further arranged between the flanging ( 16 ) and the connection rod guiding unit ( 13 ) or is arranged on a side face of the flanging ( 16 ). 
     A plurality of cartridges ( 3 ) may be arranged in the casing ( 20 ) of the invention, and the bottoms of the cartridges ( 3 ) are fixedly connected with the casing ( 20 ) through bolts and nuts, thus the cartridges ( 3 ) can be fixed by aligning the bottoms of the cartridges ( 3 ) with screw holes of the casing ( 20 ) and tightening the nuts so as to prevent the cartridges ( 3 ) from rotating in the casing ( 20 ). 
     The snap ring ( 24 ) may be composed of two half snap rings matched with each other so as to fixedly connect the cartridge ( 3 ) and the casing ( 20 ). 
     The casing ( 20 ) of the invention is prism-shaped and made of an aluminum material, thus reducing cost and achieving a good cooling effect. 
     The bottom end of the casing ( 20 ) of the invention is further provided with a bent handlebar ( 23 ); piezoelectric ceramics and a safety pin are arranged in the bent handlebar ( 23 ); the safety pin is unlocked through a pull ring arranged out of the bent handlebar ( 23 ); the bent handlebar ( 23 ) may be further provided as a telescopic bent handlebar, which is convenient to start and operate. 
     The portable fire extinguishing apparatus of the invention mainly has the following advantages: 
     1. the cartridge of the invention is fixed in the casing through the bolts and nuts at the bottom and the snap ring at the top, which on the one hand facilitates installation, and on the other hand allows the cartridge to be fixed appropriately within the casing, thus not easily rotated or loosened, also, obviated is the need for a production site that is required while waiting for silicone solidification by leaving to stand for seven to eight hours when silicone injection for fixing is used, thus improving production efficiency; 
     2. the fire extinguishing apparatus of the invention is provided with the explosion venting device on the cartridge, thus consuming or reducing a recoil force or a forward impact force generated by deflagration of an explosive to vent explosion safely and effectively and avoid injuries and damages caused after deflagration of the grain mainly through consuming kinetic energy generated by the deflagration in a shifting and limiting process of the explosion venting device; 
     3. the connection rod and the cartridge cover of the cartridge of the invention are connected and apply a structure of a flanging and a clamping claw, thus effectively controlling a motion of the connection rod, and the structure can effectively prevent a powerful impact force from acting on the cartridge cover of the cartridge to thrust the cartridge cover apart from the cartridge, thus preventing accidental injuries caused after the cartridge cover flies outwards; 
     4. the invention is started by piezoelectric ceramics, thus avoiding replacement of batteries and routine maintenance and saving maintenance costs. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a structural diagram of a fire extinguishing apparatus of the invention; 
         FIG. 2  is a structural diagram of a cartridge of the invention; 
         FIG. 3  is a sectional view of a structure of a cartridge of the invention; and 
         FIG. 4  is a partial structural diagram of a fire extinguishing apparatus of the invention (bottom cover not shown). 
     
    
    
     In the drawings:  1 —fire extinguishing apparatus,  2 —explosion venting device,  3 —cartridge,  4 —cartridge cover,  5 —ceramic cellular cooling layer,  6 —coolant,  7 —grain,  8 —ignition head,  9 —sealing ring,  10 —rubber plug,  11 —frictional layer,  12 —connection rod,  13 —connection rod guiding unit,  14 —connection rod limiting device,  15 —guiding ring,  16 —flanging,  17 —clamping claw,  18 —elastic body,  19 —heat insulation layer,  20 —casing,  21 —bottom cover,  22 —top cover,  23 —bent handlebar,  24 —clamping ring. 
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     The invention provides a portable fire extinguishing apparatus and preferred embodiments of the invention will be further described in combination with the accompanying drawings: 
     Referring to  FIG. 1 , the fire extinguishing apparatus  1  is mainly composed of a casing  20 , a bottom cover  21  and a top cover  21  of the casing  20 , a cartridge  3 , a cartridge cover  4  of the cartridge, an explosion venting device  2  and a bent handlebar  23 , wherein the casing  20  is prism-shaped and made of an extruded aluminium material, thus achieving a good cooling effect; the top cover  22  and the bottom cover  21  of the casing  20  are matched with the casing  20 , and the lower ends of the top cover and the bottom cover extend into the casing  20  respectively; the bottom of the cartridge  3  of the invention is locked on the bottom cover  21  of the casing  20  through bolts and nuts, and the top of the cartridge is clamped through a snap ring  24  consisting of two half snap rings and is matched with the top cover  22  of the casing  20 , so that the cartridge  3  is tightly locked and fixed at the top and the bottom, thus preventing the cartridge from oscillating or rotating in the casing  20 ; in assembly, the top of the cartridge  3  is clamped by the two half snap rings to clamp the cartridge right in a corresponding installation hole of the top cover  22 , i.e. the top of the cartridge  3  is pressed on one half snap ring while the other half snap ring is pressed into the top cover  22  subsequently; the top cover  22  is then pressed into the aluminum casing  20 ; then the bottom cover  21  is installed and the bottom of the cartridge  3  is locked and attached with the bottom cover  21  to complete assembly of the cartridge  3 . A plurality of cartridges  3  may be arranged in the casing  20 , preferably three. 
     Referring to  FIG. 2  and  FIG. 3 , the cartridge cover  4  of the cartridge may be further arranged on the top end of the cartridge  3  of the invention; a ceramic cellular cooling layer  5 , a coolant  6 , a grain  7  and an ignition head  8  arranged on the section of the front end of the grain  7  are arranged in the cartridge  3  in turn; generally, the cartridge  3  and the cartridge cover  4  of the cartridge are connected hermetically through a sealing ring  9 , wherein the section of the sealing ring  9  may be square, circular or in other shapes; the cartridge cover  4  of the cartridge comprises a spout and a trumpet nozzle, and the center of the spout faces the center of the trumpet nozzle; the spout may be sealed by a rubber plug  10  or an aluminium foil; in addition, the ceramic cellular cooling layer  5  can fix the coolant  6  to prevent the coolant from dropping out on one hand, and have a physical cooling effect to reduce the temperature of a high temperature hot aerosol on the other hand; generally, the ceramic cellular cooling layer  5  may be arranged at the front end of the coolant  6 , may be also provided in the middle of the coolant  6 , or may be also provided at both the front end and the middle section of the coolant  6 , and the positions and quantity of ceramic cellular cooling layers are determined according to actual application conditions; one end of the trumpet nozzle having a relatively large diameter of the invention is connected with the cellular cooling layer, thus guiding an aerosol to be ejected from the spout, and the trumpet nozzle may be integrated with the cartridge cover; a heat insulation layer  19  may be further added between the grain  7  and the inner wall of the cartridge  3  to have a heat insulation effect and prevent people or materials from being burnt by heat generated after ignition of the aerosol. 
     The explosion venting device  2  of the invention mainly comprises a frictional layer  11 , a connection rod  12 , a connection rod guiding unit  13 , a connection rod limiting device  14  and an elastic body  18 , wherein the connection rod  12  is connected on the cartridge cover  4  of the cartridge, and may be fixedly connected through welding and rivet joint etc., or may be also integrated directly, thus the structural strength is higher; the frictional layer  11  may be one or more rubber rings or silicone layers or other materials capable of providing enough frictional resistance for axial sliding of the connection rod  12 ; the frictional layer  11  may be arranged between the connection rod  12  and the cartridge  3 , or may be directly fixed at an inner side of the connection rod  12 ; the frictional layer  11  provides a frictional resistance and a buffering force for the connection rod  12  when the same is guided by the connection rod guiding unit  13  to displace along an axial direction of the cartridge  3 ; the connection rod guiding unit  13  is a device capable of providing a guiding function for the connection rod  12  when the same is moving, and may be a guiding ring  15  fixedly connected with the connection rod  12 , or may be also a guiding groove provided on the outer wall of the cartridge  3  and capable of enabling the connection rod  12  to slide along the guiding groove, or other structures having a guiding function; this guiding structure can prevent the connection rod  12  from being offset or locked during a moving process of the cartridge  3 ; when the guiding ring  15  is applied to guiding, the guiding ring  15  may be fixedly connected with an extremity of the connection rod  12  or directly integrated with the connection rod  12 ; the connection rod limiting device  14  of the invention is fixedly connected with the cartridge cover  4  of the cartridge and the connection rod  12 ; when the extremity of the connection rod  12  reaches a position as illustrated of the cartridge cover  4  of the cartridge, the connection rod is limited by the connection rod limiting device  14 ; the connection rod limiting device  14  mainly comprises a flanging  16  and a clamping claw  17 , wherein the flanging  16  and the cartridge  3  are fixedly connected, or may be also integrated directly, and one end of the clamping claw  17  is fixed on the connection rod  12  while the other end is clamped with the cartridge  3  to mainly fix the connection rod  12 ; the connection rod  12  may be also integrated with the clamping claw  17 , or the connection rod limiting device  14  of the invention may be also other structures, as long as the connection rod  12  can be fixed on one hand, and the connection rod  12  can be blocked and prevented from being detached from the cartridge  3  on the other hand. The elastic body  18  may be further arranged between the flanging  16  of the invention and the connection rod guiding unit  13 , or may be arranged on a side face of the flanging  16  to mainly buffer a collision force between the extremity of the connection rod  12  and the cartridge  3  or between the extremity of the connection rod  12  and the flanging  16 , prolong collision time and release, by using the elastic property of the elastic body, a part of kinetic energy generated after deflagration. 
     The displacement of the connection rod  12  of the invention is preferably controlled within 50 to 60 mm, because excessive displacement will fail to reduce a recoil force; however, the kinetic energy cannot be consumed thoroughly by little displacement, and the cartridge cover of the cartridge is very likely to get rid of the blockage of the connection rod limiting device ( 14 ); once the cartridge cover of the cartridge is separated from the cartridge, a powerful recoil force will be generated; however, the displacement of the connection rod  12  may be adjusted appropriately according to a specific application environment, as long as an optimal explosion venting effect can be realized. 
     When the gain  7  of an inner cartridge is ignited and released normally, hot air is released from the spout of the cartridge cover  4  of the cartridge, and an oversize air stream will not be generated, thus the explosion venting device  2  will not be started; the connection rod  12 , which is fixed on the cartridge  3  by the clamping claw  17 , will not move to generate displacement along an axial direction of the cartridge  3 ; only when the cartridge cover  4  of the cartridge and the connection rod  12  are pushed by a powerful hot air stream generated by unexpected explosive deflagration to move in a direction towards which the hot air stream is ejected, the clamping claw  17  of the connection rod limiting device  14  slips under the action of a powerful impact force on one hand to consume a part of the impact kinetic energy; pushed by the hot air stream, the connection rod  12  drives the guiding ring  15  to slide axially along the outer wall of the cartridge  3  to generate displacement, and the frictional layer  11  generates frictional resistance to the connection rod during the moving process to consume a part of the impact kinetic energy; when the extremity of the connection rod  12  reaches the spout of the cartridge  3 , the flanging  16  of the connection rod limiting device  14  fixed on the cartridge  3  stops the extremity of the connection rod  12  from being separated from the cartridge  3 ; at the moment, the elastic body  18  arranged between the flanging  16  and the guiding ring  15  functions to consume a part of the impact kinetic energy with its elasticity, and buffers the powerful impact force between the extremity of the connection rod  12  and the flanging  16  additionally; when the final kinetic energy acts on the flanging  16  in the form of collision, the flanging  16  is deformed elastically or plastically, which will consume all remaining kinetic energy; thus the powerful impact kinetic energy generated by deflagration of the grain  7  may be well consumed or dispersed in the whole process to avoid injuries or damages brought thereby. 
     A bent handlebar  23  extending out of the casing  20  is further provided at the bottom of the casing  20  of the invention, wherein a PC elastic sheet, piezoelectric ceramics and a safety pin are arranged in the bent handlebar  23 ; the safety pin is unlocked through a pull ring provided outside the bent handlebar  23 ; a starting push button may be arranged on a position that facilitates operation out of the bent handlebar  23 , and may be started when pressed. A fixing cover is further arranged outside the bottom cover  21  of the casing  20  to fix the bent handlebar  23  on the bottom cover  21  through five bolts; the bent handlebar may be further provided as a telescopic bent handlebar which is pulled out in use and may be retracted when not in use, thus saving space. In use, the pull ring is pulled out to unlock the safety pin, and the press button is pressed to start the fire ignition head  8  of the fire extinguishing apparatus  1  through the piezoelectric ceramics, thus starting the fire extinguishing apparatus  1 . 
     In the  FIG. 4 , a reference number  27  shows the feature “bolts”, a reference number  28  shows the feature “nuts”, a reference number  25  shows the feature “piezoelectric ceramics”, a reference number  26  shows the feature “safety pin”, a reference number  23  shows the feature “the telescopic bent handlebar”.