Abstract:
A portable fire extinguisher includes a housing ( 3 ) and a cartridge ( 4 ) arranged within the housing ( 3 ). The cartridge ( 4 ) is fixedly connected at a bottom thereof to the housing ( 3 ) via a fastening device ( 40 ). This on the one hand facilitates shifting, and on the other hand allows the cartridge ( 4 ) to be fixed appropriately in the housing ( 3 ), thus not easily rotated or loosened, also, the need of a production site for waiting for silicone solidification by standing for seven to eight hours is avoided when silicone injection for fixing is used, thus improving production efficiency.

Description:
TECHNICAL FIELD OF THE INVENTION 
       [0001]    The present disclosure belongs to the field of fire fighting technology, and particularly relating to a portable fire extinguisher. 
       BACKGROUND OF THE INVENTION 
       [0002]    At present, existing portable fire extinguishers are generally divided into stored-pressure dry powder fire extinguishers and portable aerosol fire extinguishers, wherein the stored-pressure dry powder fire extinguisher mainly have the following disadvantages: firstly, the stored-pressure dry powder fire extinguisher causes serious pollution to the environment and serious damage to articles; secondly, the stored-pressure dry powder fire extinguisher, which needs to store high pressure gases, is large in volume and heavy in weight; thirdly, the stored-pressure dry powder fire extinguisher, which is a high pressure container, has potential safety hazards and is more dangerous in a high temperature environment of a fire; fourthly, the stored-pressure dry powder fire extinguisher, which needs to go through regular inspection and verification, is high in routine maintenance costs etc. By contrast, the portable aerosol fire extinguisher has obvious advantages and mainly includes: 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 grain 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 grain. As a result, a high pressure gas will thrust the cartridge cover forwards and will be vented rapidly to throw the cartridge cover and other things in the cartridge forwards at an extremely high speed, thus causing a very large recoil force. The powerful recoil force drives the cartridge to move backwards rapidly, which is easy to cause an injury to an operator. At the same time, after explosion venting, the cartridge cover etc. of the fire extinguisher 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 fire extinguisher is easy to be loosened in an outer housing and is fixed by filling silicone in the cartridge body currently. However, the method generally needs to wait for silicone solidification by standing for seven to eight hours after silicone injection, thus a relatively large production site is required and the production efficiency is relatively low. Therefore, the problem of fixation of the cartridge of the fire extinguisher is a subject to be solved. 
       SUMMARY OF THE INVENTION 
       [0003]    To solve disadvantages existing in a portable fire extinguisher in the prior art, the present disclosure provides a simple and convenient portable fire extinguisher capable of greatly reducing a production site and effectively preventing explosion and releasing pressure, and reducing a recoil force. 
         [0004]    The technical solution adopted by the present disclosure to solve the technical problem above is: 
         [0005]    A portable fire extinguisher includes a housing and a cartridge arranged within the housing; the top of the cartridge is provided with a cartridge cover, wherein a bottom of the cartridge is fixedly connected to the housing via a fastening device. This on the one hand facilitates shifting, and on the other hand allows the cartridge to be fixed appropriately in the housing, thus not easily rotated or loosened, also, the need of a production site for waiting for silicone solidification by standing for seven to eight hours is avoided when silicone injection for fixing is used, thus improving production efficiency. 
         [0006]    The fastening device of the present disclosure mainly includes a screw provided at the bottom of the cartridge, a nut matched with the screw and a rotation-stopping body provided at the bottom of the housing and capable of preventing the screw from rotating. 
         [0007]    The fastening device of the present disclosure may be also a screw running through the bottom of the housing to fixedly connect the housing with the bottom of the cartridge. 
         [0008]    A top end of the cartridge of the present disclosure is provided with an explosion venting device; the explosion venting device includes a frictional layer, a connection rod, a connection rod guiding unit and a connection rod limiting device, wherein the connection rod is connected with the cartridge cover; the frictional layer is provided between the connection rod and an outer wall of the cartridge; when the connection rod is guided by the connection rod guiding unit to displace along a direction of a hot air stream ejected by the cartridge, the frictional layer provides a frictional resistance and a buffering force for the connection rod; the connection rod guiding unit is a device capable of providing a guiding function for the connection rod when the same is moving; the connection rod limiting device is a device capable of limiting the connection rod when an extremity of the connection rod reaches an spout of the cartridge. By consuming, in a shifting and limiting process of the explosion-venting device, kinetic energy generated by deflagration, a recoil force or a forward impact force generated after deflagration of an explosive can be consumed or reduced to vent explosion safely and effectively and avoid injuries or damages caused after deflagration of the cartridge. 
         [0009]    The connection rod guiding unit is a guiding ring fixedly connected with the connection rod, or is a guiding groove provided on the outer wall of the cartridge and capable of enabling the connection rod to move axially along the guiding groove; the connection rod limiting device includes a flanging fixedly connected with a jet end of the cartridge and a clamping claw for fixing the connection rod; an elastic body is arranged between the flanging and the connection rod guiding unit, or is arranged on a side surface of the flanging. 
         [0010]    The housing of the present disclosure includes a top cover; the top cover includes a top cover body and a clamping wall fixedly connected thereto; the clamping wall is arranged at an inner side of the top cover body and an extremity of the clamping wall is provided with a clamping hook, and a cavity is reserved between the clamping hook and the top cover body; a fixture block is arranged in the cavity between the clamping wall and the top cover body; the cartridge and the fixture block are respectively clamped at two sides of the clamping wall to effectively prevent deformation thereof and prevent the cartridge from being loosened by the deformation of the clamping wall of the top cover. 
         [0011]    The bottom of the housing of the present disclosure is provided with a base with a handle and an extension and retraction control device provided thereon; extension and retraction of the handle are implemented through the extension and retraction control device, thus further saving storage space to facilitate operation and facilitating transportation and storage. 
         [0012]    The extension and retraction control device mainly includes a locating groove arranged on the base and capable of enabling the handle to slide along the locating groove, and a limiting device capable of limiting the sliding of the handle. Limited by the locating groove, offsetting and locking during an extension and retraction process are prevented, and the limiting device performs limiting control for extension and retraction of the handle. 
         [0013]    The limiting device mainly includes a limiting elastic sheet, a limiting screw and a limiting groove; the limiting elastic sheet is arranged in the locating groove; one side surface of the handle is provided with the limiting screw clamped with the base and the other side surface of the handle ( 10 ) is provided with the limiting groove for making the limiting elastic sheet locked; a bottom cover of the base is provided thereon with a chute capable of enabling the limiting screw to slide along the chute and capable of limiting the limiting screw. 
         [0014]    The handle includes a curved bar and a holder; the curved bar is arranged in the locating groove and capable of sliding along the locating groove; the holder is arranged at an extremity of the curved bar. 
         [0015]    A cavity may be arranged on both the curved bar and the holder; a push button and piezoelectric ceramics are arranged in the holder in turn; one end of the push button extends outside the holder and the other end is provided with a pin hole; an elastic clamping claw and a convex ring are arranged on the pin hole; the outer wall of the handle is provided with a safety pin; a side wall of one end of the safety pin is provided with a concave ring locked with the convex ring and an extremity of the safety pin extends into the pin hole to be locked and tightly clamped with the convex ring through the elastic clamping claw and the concave ring to fasten the safety pin; the other end of the safety pin is provided with a pull ring so that the pull ring can be pulled out. 
         [0016]    The curved bar and the holder are hollow structures; a push button and a piezoelectric ceramics are arranged in the holder in turn; one end of the push button ( 33 ) extends outside the holder ( 32 ) and the other end is provided with a pin hole; a limiting ring is arranged outside the pin hole; an outer wall of the holder is provided with a safety pin; the safety pin includes a connection part and a clamping head connected to the lower end of the connection part; the clamping head includes one or more first elastic sheets and a second elastic sheet connected to extremity of the first elastic sheet and forming included angle with the first elastic sheets; the first elastic sheet and the second elastic sheet are respectively provided with degrees of freedom; an extremity of the second elastic sheet extends outside the pin hole and is limited through the limiting ring; the upper end of the connection part is provided with a pull ring. 
         [0017]    The portable fire extinguisher of the present disclosure mainly has the following advantages: 
         [0018]    1. the cartridge of the present disclosure is fixed in the housing through the fastening device, which on the one hand facilitates installation, and on the other hand allows the cartridge to be fixed properly in the housing, thus not easily being rotated or loosened; and the need of a production site for waiting for silicone solidification by standing for seven to eight hours is avoided when silicone injection for fixing is used, thus improving production efficiency. 
         [0019]    2. the fire extinguisher of the present disclosure 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 cartridge mainly through consuming kinetic energy generated by the deflagration in a shifting and limiting process of the explosion venting device; the aim of a forward movement is to release pressure while the aim of limited displacement and final limiting are to reduce the recoil force. 
         [0020]    3. the connection rod of the present disclosure is connected with the cartridge cover of the cartridge, and adopts 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 so as to prevent accidental injuries caused after the cartridge cover flies outwards; 
         [0021]    4. the present disclosure mainly adopts filling the fixture block in the cavity between the clamping wall of the top cover and the top cover body so that the inner and outer sides of the clamping wall are fully filled; the cartridge is provided at the inner side and the fixture block is provided at the outer side, thus ensuring that the clamping wall will not deform, so that a relatively large extrusion force and axial tensioning force can be born so as to ensure that the cartridge can be clamped tightly; in addition, the present disclosure is simple in structure and convenient in installation. 
         [0022]    5. the present disclosure is provided with a telescopic handle, which is convenient in packaging and transportation and saves storage space; more specifically, by the locating groove and the limiting elastic sheet arranged on the base and the limiting screw on the handle and so on, it can be ensured that the handle can be fixed and will not be separated from the housing after being pulled out, and problems of offsetting and locking dead can be also avoided; 
         [0023]    6. the safety pin of the present disclosure is clamped tightly through the concave ring provided on the side wall of the safety pin and the elastic clamping claw on the pin hole, or is locked safely through a connection head provided on an extremity of the safety pin and capable of being limited by the limiting ring on the pin hole, thus the safety pin will not fall off easily so as to avoid the danger of error starting; in addition, the safety pin may be utilized repeatedly. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0024]      FIG. 1  is a structural diagram of a fire extinguisher of the present disclosure; 
           [0025]      FIG. 2  is a sectional view of a structure of a fire extinguisher of the present disclosure; 
           [0026]      FIG. 3  is a partial enlarged drawing of  FIG. 2 ; 
           [0027]      FIG. 4  is a structural diagram of a cartridge of the present disclosure; 
           [0028]      FIG. 5  is a sectional view of a structure of a cartridge of the present disclosure; 
           [0029]      FIG. 6  is a schematic diagram of an embodiment of a fastening device of the present disclosure; 
           [0030]      FIG. 7  is a structural diagram of a screw of the present disclosure; 
           [0031]      FIG. 8  is a structural diagram of a rotation-stopping body of the present disclosure; 
           [0032]      FIG. 9  is a sectional view of a structure of a handle of the present disclosure; 
           [0033]      FIG. 10  is a structural diagram of a holder of the present disclosure; 
           [0034]      FIG. 11  is a structural diagram of a base of the present disclosure; 
           [0035]      FIG. 12  is a structural diagram of a bottom cover of the present disclosure; and 
           [0036]      FIG. 13  is a structural diagram of an optimal embodiment of a safety pin of the present disclosure. 
       
    
    
       [0037]    In the drawings:  1 —fire extinguisher,  2 —explosion venting device,  3 —housing,  4 —cartridge,  5 —cartridge cover,  6 —top cover,  7 —base,  8 —base body,  9 —bottom cover,  10 —handle,  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 —top cover body,  20 —clamping wall,  21 —clamping hook,  22 —fixture block,  23 —clamping point,  24 —extension and retraction control device,  25 —locating groove,  26 —limiting elastic sheet,  27 —limiting screw,  28 —limiting groove,  29 —limiting device,  30 —starting device,  31 —curved bar,  32 —holder,  33 —push button,  34 —piezoelectric ceramics,  35 —pin hole,  36 —elastic clamping claw,  37 —safety pin,  38 —pull ring,  39 —chute,  40 —fastening device,  41 —screw,  42 —rotation-stopping body,  43 —bump,  44 —connection part,  45 —clamping head,  46 —first elastic sheet,  48 —concave ring. 
       DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0038]    The present disclosure provides a portable fire extinguisher, and preferred embodiments of the present disclosure will be further described in combination with the accompanying drawings. 
         [0039]    Referring to  FIG. 1  and  FIG. 2 , the fire extinguisher  1  mainly consists of a housing  3 , a base  7  and a top cover  6  of the housing  3 , a cartridge  4 , a cartridge cover  5 , an explosion venting device  2  and a handle  10 , wherein the housing  3  is a columnar structure, such as a cylindrical structure, a square columnar structure or an irregular columnar structure etc. and adopts a extruded aluminium material with good cooling effect; the top cover  6  and the base  7  of the housing  3  are arranged at two ends of the housing  3 , respectively, and connection parts with the housing  3  can extend into a cavity of the housing  3 . 
         [0040]    Referring to  FIG. 3 , the top cover  6  mainly consists of a clamping wall  20  and a top cover body  19 , wherein the clamping wall  20  is fixedly connected with the top cover body  19  and is arranged between an inner side of the top cover body  19  and the top cover body  19  to form a cavity; an extremity of the clamping wall  20  is provided with a clamping hook  21  capable of clamping the cartridge cover  5  of the cartridge  4  tightly to prevent axial detachment of the cartridge cover; the top cover body  19  is connected with the wall of the housing  3 ; a cavity between the clamping wall  20  and the top cover body  19  is provided therein with a fixture block  22  having a structure matched with the cavity to fully fill the cavity, and one or more clamping points  23  capable of clamping the fixture block  22  and capable of preventing the fixture block  22  from being detached may be provided on the clamping wall  20  and the top cover body  19 . 
         [0041]    During installation, the cartridge  4  is clamped on the top cover  6  first, and the fixture block  22  is then stuck into the cavity between the clamping wall  20  and the top cover body  19  and the fixture block  22  is tightly clamped by convex points; an extremity of the cartridge  4  is then put into the housing  3  and the top cover  6  is secured to complete the installation. 
         [0042]    Referring to  FIG. 4  and  FIG. 5 , a top end of the cartridge  4  is further provided with the cartridge cover  5  of the cartridge  4 ; a ceramic cellular cooling layer, a coolant, gain and an ignition head arranged on the section of the front end of the gain are arranged in the cartridge  4  in turn; generally, the cartridge  4  and the cartridge cover  5  of the cartridge  4  are connected hermetically by a sealing ring, wherein the section of the sealing ring may be square, or may be also circular or in other shapes; the cartridge cover  5  of the cartridge  4  includes 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 or an aluminium foil; in addition, the ceramic cellular cooling layer can on one hand fix the coolant to prevent the coolant from dropping out, and on the other hand have a physical cooling effect to reduce the temperature of a high temperature hot aerosol; generally, the ceramic cellular cooling layer may be arranged at the front end of the coolant, or may be provided in the middle of the coolant, or may be also provided at both the front end and the middle section of the coolant, and the positions and quantity of ceramic cellular cooling layers are determined according to actual application conditions; one end of the trumpet nozzle with a relatively large diameter of the present disclosure may be 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  5 ; a heat insulation layer may be further added between the grain and the inner wall of the cartridge  4  to have a heat insulation effect and prevent people or materials from being burnt by heat generated after ignition of the aerosol. 
         [0043]    The explosion venting device of the present disclosure mainly includes 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  5  of the cartridge  4 , and may be fixedly connected with the cartridge cover  5  through welding and pivoting etc., or may be also integrated directly with the cartridge cover  5 , 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  4 , or may be directly fixed at an inner side of the connection rod  12 ; when the connection rod  12  is guided by the connection rod guiding unit  13  to displace along an axial direction of the cartridge  4 , the frictional layer  11  provides a frictional resistance and a buffering force for the connection rod; the connection rod guiding unit  13  is a device capable of providing a guiding function for the connection rod  12  when the connection rod  12  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 an outer wall of the cartridge  4  and capable of enabling the connection rod  12  to move axially along the guiding groove, or other structures having a guiding function; this guiding structure can prevent the connection rod  12  from being offset or clamped during a moving process of the cartridge  4 ; when the guiding ring  15  is applied to guiding, the guiding ring  15  may be fixedly connected or directly integrated with an extremity of the connection rod  12 ; the connection rod limiting device  14  of the present disclosure is fixedly connected with the cartridge cover  5  of the cartridge  4  and the connection rod  12 ; when the extremity of the connection rod  12  reaches a position as illustrated of the cartridge cover  5  of the cartridge  4 , the connection rod is limited by the connection rod limiting device  14 ; the connection rod limiting device  14  mainly includes a flanging  16  and a clamping claw  17 , wherein the flanging  16  is fixedly connected with the cartridge  4 , or may be also integrated directly with the cartridge  4 , and one end of the clamping claw  17  is fixed on the connection rod  12  while the other end of the clamping claw  17  is clamped with the cartridge  4  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 present disclosure 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  4  on the other hand. The elastic body  18  may be further arranged between the flanging  16  of the present disclosure and the connection rod guiding unit  13 , or may be arranged on a side surface of the flanging  16  to mainly buffer a collision force between the extremity of the connection rod  12  and the cartridge  4  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. 
         [0044]    The displacement of the connection rod  12  of the present disclosure is preferably controlled within a range of 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  5  of the cartridge  4  is very likely to get rid of the blockage of the connection rod limiting device  14 ; once the cartridge cover  5  of the cartridge  4  is separated from the cartridge  4 , 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. 
         [0045]    When the gain  7  of an inner cartridge is ignited and released normally, hot air is released from the spout of the cartridge cover  5  of the cartridge  4 , 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  4  by the clamping claw  17 , will not move to generate displacement along an axial direction of the cartridge  4 ; only when the cartridge cover  5  of the cartridge  4  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 off 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  4  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  4 , the flanging  16  of the connection rod limiting device  14  fixed on the cartridge  4  stops the extremity of the connection rod  12  from being separated from the cartridge  4 ; 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 by 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. 
         [0046]    Referring to  FIG. 6 ,  FIG. 7  and  FIG. 8 , a bottom of the cartridge  4  of the present disclosure is fixedly connected with the housing  3  through a fastening device  40 ; the base  7  of the present disclosure mainly includes a base body  8  and a bottom cover  9  arranged outside the base body  8 . The fastening device  40  may be implemented in various ways; in the present embodiment, the fastening device mainly includes a screw  41 , a nut matched with the screw  41  and a rotation-stopping body  42  capable of preventing the screw  41  from rotating. The rotation-stopping body  42  may be directly integrated with the base body  8  or may be provided separately and fixed on the base body  8 . A bump  43  is arranged on the rotation-stopping body  42 , and is directly arranged on the base body  8  and locked with a groove on the screw  41  when integrated with the base body  8 . The screw  41  is fixedly connected with the bottom of the cartridge  4 , and may be fixed on the bottom of the cartridge  4  through welding, or may also run through and be fixed with the bottom of the cartridge  4  from inside to outside, and is axially provided with a through groove to be fitted with the bump  43 . A threaded hole corresponding with the screw  41  is provided on the base  7  of the housing  3  of the present disclosure; the bump  43  is provided on the threaded hole and matched with the structure of the screw  41  so that the bump  43  may be embedded into the through groove of the screw  41 , while the screw  41  runs through the rotation-stopping body  42  and extends outside the threaded hole, and assembly can be finished after the nut is tightened. When the nut is tightened, the threaded hole locks the rotation-stopping body  42  to prevent the rotation-stopping body  42  from rotating, while the bump  43  embedded into the through groove of the screw  41  is limited by the rotation-stopping body  42 , namely the base body  8  in the present embodiment and will not rotate, thus blocking the screw  41  from rotating. The nut is tightened, and the cartridge  4  is fixed with the housing  3 . A bump may be also provided on the side wall of the screw  41  and a groove may be provided on the side wall of the rotation-stopping body  42 , and so on, and any structure may be applied as long as the rotation-stopping body  42  is enabled to stop the screw  41  from rotating. 
         [0047]    A handle  10  is further arranged on the base  7  of the present disclosure; the handle  10  may have a structure of a handle  10  in the prior art, or may be also a handle  10  with another structure, mainly aiming at facilitating carrying and operation. Referring to  FIG. 9 ,  FIG. 11  and  FIG. 12 , the handle  10  of the present embodiment may adopt a telescopic handle  10 , wherein the handle  10  mainly consists of a curved bar  31  and a holder  32 , and is fixedly connected through a screw, sleeving, clamping or other ways. The curved bar  31  may adopt a metal material, may be moulded through injection, or may be manufactured through other processes. The holder  32  may be a plastic material, and the plastic material may be also replaced by other material, and the material is not limited thereto and may be determined according to a specific application environment. When extending and retracting, it is mainly that one end of the curved bar  31  extends into the base body  8 , and extends and retracts on the base body  8 , i.e. the handle  10  extends and retracts on the base  7  mainly through an extension and retraction control device. The extension and retraction control device mainly includes a locating groove  25  and a limiting device  29 . The locating groove  25  is arranged on the base body  8  so that the curved bar  31  can slide along the locating groove. The limiting device  29  mainly consists of a limiting elastic sheet  26 , a limiting screw  27  and a limiting groove  28 , and mainly aims at having a limiting and controlling function during an extension and retraction process of the curved bar  31 . The limiting elastic sheet  26 , which is arranged in the locating groove  25 , may be integrated with the locating groove  25 , or may be also an independent detachable component, and mainly needs to provide certain elasticity. The limiting elastic sheet will not limit the sliding of the curved bar  31  when the curved bar  31  is sliding. However, when the curved bar  31  slides to a certain position and needs to be located, the limiting elastic sheet is reset by the elasticity thereof so as to be locked with the limiting groove  28  provided on a corresponding position on the curved bar  31  to limit the curved bar  31 . The limiting screw  27  is provided on a side surface of the curved bar  31  opposite to the limiting groove  28 ; the limiting screw  27  is matched with a chute  39  arranged on the bottom cover  9  of the base  7 . When the curved bar  31  slides, the limiting screw  27  will slide along the chute  39  and will not generate offsetting. When the curved bar  31  slides to a predetermined displacement, the limiting screw  27  will be jammed in the chute  39  to prevent the curved bar  31  from being separated from the base body  8 . In this way, both sides of the curved bar  31  are limited, so that the curved bar is located precisely and will not be detached or offset and so on. 
         [0048]    The curved bar  31  and the holder  32  of the present disclosure are arranged with cavities, so it is beautiful in appearance and saves wiring space. However, grooves or U-shaped grooves and so on may be also provided therewith. 
         [0049]    Referring to  FIG. 10 , a starting device  30  is arranged in the holder  32  of the present disclosure, i.e. a push button  33  and piezoelectric ceramics  34  arranged in turn. One end of the push button  33  extends outside the holder  32  and the other end thereof faces a trigger end of the piezoelectric ceramics  34 . One end of the push button  33  facing the piezoelectric ceramics  34  is further provided with a pin hole  35  to install a safety pin  37  so as to prevent the push button  33  from being started by mistake. At the same time, the pin hole  35  further needs to limit the safety pin  37  to prevent the safety pin from being easily loosened or detached. The safety pin  37  of the present disclosure is arranged on the holder  32 ; one end of the safety pin is provided with a pull ring  38  and exposed out of the holder  32 , and the other end extends into the pin hole  35 ; in addition. The side wall of the other end is provided with a concave ring  48 , and a convex ring is provided at a corresponding position of the pin hole  35 , and the concave ring and the convex ring are locked with each other. In addition, an elastic clamping claw  36  is arranged at the opening of the pin hole  35 , and right clamps an extremity of the safety pin  37  so that the safety pin  37  inserted into the pin hole  35  can be well secured and will not be detached easily. The safety pin  37  can be pulled out only with an external force that is large enough. 
         [0050]    The safety pin  37  of the present disclosure may be also of a structure as shown in  FIG. 13 , and mainly includes a connection part  44 , a clamping head  45 , and the pull ring  38 , wherein the pull ring  38  is provided at the upper end of the connection part  44 . The pull ring  38  may be fixedly connected and integrated with the connection part  44 , or run through a through hole provided on the connection part  4 . The main function of the pull ring  38  is that, when detachment is required, the pull ring  38  is pulled to transmit a force to the connection part  44  and the clamping head  45  to implement detachment. If detachment is not required, it is unnecessary to provide pull ring  38 . A middle section of the connection part  44  is provided with a reducing hole so that the wall thickness thereof is uniform and shrinkage can be prevented. The clamping head  45  is provided at the lower end of the connection part  44 , and they may be manufactured separately and finally combined through methods including injection and filling, adhesion, interference fit, screw fastening, connection with a connection pin, ultrasonic welding, clamping with plastic clamping hook etc., or may be directly integrated. The clamping head  45  of the present disclosure includes a first elastic sheet  46  and a second elastic sheet  47  connected to an extremity of the first elastic sheet  46 , wherein there is a certain included angle between the first elastic sheet  46  and the second elastic sheet  47 , i.e. the first elastic sheet and the second elastic sheet are connected in a cross manner to form a “V” shape, an “L” shape or a “J” shape etc. The included angle therebetween needs to be adjusted according to actual application conditions. The first elastic sheet  46  and the second elastic sheet  47  are provided with a degree of freedom, respectively, and may be deformed according to directions of their respective degrees of freedom when an external force is too large. A structure formed by the first elastic sheet  46  and the second elastic sheet  47  is applicable to implement two degrees of freedom as long as a certain tensile force can be overcome to implement a “clamping” function on one hand, and on the other hand, the structure can be stretched and straightened when the tensile force is too large and exceeds the endurance thereof. The wall thickness of the upper end of the first elastic sheet  46  is larger than the wall thickness of the lower end, while the second elastic sheet  47  may be also adjusted according to use conditions and the thickness thereof is not unique. There may be one or two or more clamping heads  45 . When there is a plurality of clamping heads, the clamping heads are optimally distributed at the lower end of the connection part  44  in a uniform manner. When there is an even number of clamping heads, the clamping heads are provided symmetrically and may be arranged into a matrix, arranged circumferentially or arranged into a curve, which needs to be determined according to an application environment. A limiting ring is provided out of the opening of the pin hole  35 . After the safety pin  37  is inserted, the extremity of the second elastic sheet  47  is right clamped at the opening of the pin hole  35  and limited by the limiting ring so that it is not easily deformed or offset when pulled out. 
         [0051]    In order to improve the durability of the clamping head  45 , the clamping head  45  is optimally made of an injection material, i.e. a Polyamide material (PA66), PE, PP, ABS, PC or a PC alloy etc., preferably the Polyamide 66 material (PA66). The connection part  44  and the clamping head  45  may adopt the same material, i.e. both of them adopt the injection material Polyamide 66 material (PA66), thus improving the abrasive resistance, the tensile resistance and the number of recycling times thereof. 
         [0052]    In normal conditions of the portable fire extinguisher of the present disclosure, the safety pin  37  should be clamped in the pin hole  35 , tightly; the push button  33  is fixed by the pin hole  35  and cannot move;. Therefore, the piezoelectric ceramics  34  cannot be started to start a fire extinguishing agent, and the limiting screw of the handle  10  is clamped in the chute  39  while the limiting elastic sheet is clamped in the limiting groove of the handle  10 . In use, the handle  10  is pulled out first for operation; subsequently, the safety pin  37  is pulled out and the push button  33  is pressed so that the piezoelectric ceramics  34  is started by the push button  33  to ignite an explosive in the cartridge. A generated hot aerosol is cooled by a chemical coolant and a cellular ceramic body, and simultaneously, the coolant undergoes some chemical and physical changes, and the hot aerosol is ejected through the spout of the grain to extinguish a fire.