the invention relates to a portable fire extinguishing device , and preferred embodiments of the invention will be further described in combination with the drawings . referring to fig1 and fig2 , the fire extinguishing device of the invention comprises a casing 1 and a cartridge 2 provided inside the casing 1 ; the casing 1 of the invention mainly comprises a first half casing 4 , a second half casing 5 , a fastening ring 6 and a bottom cover 7 . the first half casing 4 and the second half casing 5 are structurally fitted and provided symmetrically to form a cylindrical structure , i . e . the section of the structure after the combination is circular , square , or in other closed shapes . the two sides of the first half casing 4 and the second half casing 5 are respectively provided with multiple clamping hooks 8 and clamping holes 9 , and the first half casing 4 and the second half casing 5 are connected closely through locking of the clamping hooks 8 and the clamping holes 9 , wherein the positions of the clamping hooks 8 and the clamping holes 9 on the first half casing 4 and the second half casing 5 may be switched , as long as the first half casing 4 and the second half casing 5 can be fixed through clamping and locking to form an integral body with a closed side face . the first half casing and the second half casing may be also fixed through other methods comprising threaded connection , riveting , or ultrasonic welding etc . referring to fig3 and fig4 , in order to implement accurate alignment and more reliable connection , the middle parts of the first half casing 4 and the second half casing 5 may be further locked through bolts . the inner walls of the first half casing 4 and the second half casing 5 are further provided with clamping ribs 11 capable of implementing axial locating and annular ribs 11 capable of implementing radial locating ; the annular ribs 11 further need to fit the outer wall of the cartridge 2 simultaneously to tightly clamp the cartridge 2 and prevent the same from oscillating . the two ends of the first half casing 4 and the second half casing 5 of the invention can extend to the cartridge cover and the cartridge bottom of the cartridge 2 to fix the cartridge . to facilitate assembly and fixing of the cartridge 2 , the two ends of the first half casing 4 and the second half casing 5 may be further provided with the fastening ring 6 and the bottom cover 7 . to facilitate assembly and absorb a part of explosion venting energy during explosion venting , the inner walls of the fastening ring 6 and the bottom cover 7 are provided with multiple clamping points and at the same time , annular bumps 10 are provided on the corresponding outer walls of two ends of the first half casing 4 and the second half casing 5 . referring to fig5 and fig6 , the cartridge 2 of the invention is improved based on an existing cartridge 2 , and a pyrotechnic column , an ignition head on the front end face of the pyrotechnic column , a coolant , and a ceramic cellular cooling layer are provided in the cartridge in turn . in addition , a heat insulation layer is coated between the inner call of the cartridge 2 and the pyrotechnic column . or the cartridge 2 may be also a cartridge 2 of another structure applicable to the portable fire extinguishing device . another remarkable characteristic of the invention is that the jet end of the cartridge 2 is further provided with an explosion venting device 3 and the bottom end of the outer wall of the cartridge 2 is provided with a locating lug boss ; the locating lug boss further needs to fit the structures of the first half casing 4 and the second half casing 5 , i . e . clamping grooves are provided on corresponding positions of the first half casing 4 and the second half casing 5 so that the locating lug boss can be right clamped in the clamping grooves ; in this way , the cartridge 2 can be located accurately after the first half casing 4 and the second half casing 5 are folded , thus limiting the degree of freedom of the cartridge in the casing 1 . a specific structure of the explosion venting device 3 may be described as follows : it mainly comprises a frictional layer 14 , a link 13 , a link guiding unit 15 and a link limiting device 16 ; the link 13 and the cartridge cover of the cartridge 2 are fixedly connected through welding and riveting etc ., or may be directly integrated . the frictional layer 14 is provided between the link 13 and the outer wall of the cartridge 2 , and may be directly fixed on the inner wall of the link 13 . the frictional layer 14 provides a friction resistance and a buffering force for the link 13 when the same is guided by the link guiding unit 15 to displace along a direction towards which a hot air stream of the cartridge 2 is ejected . the frictional layer may be one or more rubber rings , or silicone layers or other materials capable of providing a sufficient frictional resistance for axial sliding of the link 13 . the link guiding unit 15 is a device capable of providing a guiding function for the link 13 when the same is moving , and may be a guiding ring fixedly connected with the link 13 , or may be also a guiding groove provided on the outer wall of the cartridge 2 and capable of enabling the link 13 to slide along the guiding groove , or other structures having a guiding function ; this guiding structure can prevent the link 13 from being offset or clamped during a moving process on the cartridge 2 . when the guiding ring is applied to guiding , the guiding ring may be fixedly connected or directly integrated with an extremity of the link 13 . the link limiting device 16 is a device capable of fixing the link 13 and limiting the link 13 when the extremity of the same slides to the jet end of the cartridge 2 , and mainly comprises a clamping claw 19 for fixing the link 13 and a flanging 17 for limiting the displacement of the link 13 . one end of the clamping claw 19 is fixed on the link 13 and the other end is clamped with the jet end of the cartridge 2 to mainly fix the link 13 and prevent the same from being loosened in a normal condition . the flanging 17 needs to be fixedly connected with the jet end of the cartridge 2 , and they may be welded or integrated directly , mainly aiming at preventing the link 13 or the whole explosion venting device 3 from being separated from the cartridge 2 and being out of control when the extremity of the link 13 moves to the ejecting end of the cartridge 2 . an elastic body 18 is further provided between the flanging 17 and the guiding ring or on the inner side face of the flanging 17 to have a buffering function when the extremity of the link 13 collides with the flanging 17 . the displacement of the link 13 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 cover body of the cartridge 2 is very likely to get rid of the blockage of the link limiting device 12 . once the cover body of the cartridge 2 is separated from the cartridge 2 , a powerful recoil force will be generated . however , the displacement of the link 13 may be adjusted appropriately according to a specific application environment , as long as an optimal explosion venting effect can be realized . when the pyrotechnic column is ignited and released normally , hot air is released from the cover body , and an oversize air stream will not be generated . thus the explosion venting device 3 will not be started , and the link 13 , which is fixed on the cartridge 2 by the clamping claw 19 , will not move along an axial direction of the cartridge 2 to generate displacement . only when the cover body of the cartridge 2 and the link 13 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 19 of the link limiting device 16 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 link 13 drives the guiding ring to slide axially along the outer wall of the cartridge 2 to generate displacement , and the frictional layer 14 generates frictional resistance to the link during the moving process to consume a part of the impact kinetic energy . when the extremity of the link 13 reaches the spout of the cartridge 2 , the flanging 17 of the link limiting device 16 fixed on the cartridge 2 stops the extremity of the link 13 from being separated from the cartridge 2 . at the moment , the elastic body 18 provided between the flanging 17 and the guiding ring functions to consume a part of the impact kinetic energy with its elasticity , and buffers the powerful impact force between the extremity of the link 13 and the flanging 17 additionally . when the final kinetic energy acts on the flanging 17 in the form of collision , the flanging 17 is deformed elastically or plastically , which will consume all remaining kinetic energy . thus the powerful impact kinetic energy generated by deflagration of the pyrotechnic column may be well consumed or dispersed in the whole process to avoid injuries or damages brought thereby . the fire extinguishing device of the invention is started by ignition with piezoelectric ceramics . the lower end of the piezoelectric ceramics is clamped in a corresponding installation groove at the bottom of the first half casing 4 or the second half casing 5 and the other end corresponds to starting push button provided on the wall of the second half casing 5 or the first half casing 4 . at the same time , a locating groove matched with the bottom cover 7 is provided on the bottom cover to fix the bottom cover . a safety pin capable of locking the piezoelectric ceramics and preventing the same from being started by mistake is provided on the bottom cover 7 of the casing 1 . the safety pin is connected with a pull ring exposed out of the bottom cover 7 . in use , the pull ring is pulled out first and the safety pin is unlocked ; the push button is pressed and the device can be started through the piezoelectric ceramics , thus igniting the pyrotechnic column . the portable fire extinguishing device of the invention is not limited to the structure above .
disclosed is a portable fire extinguishing device , which comprises a casing and a cartridge provided inside the casing . the device is characterized in that : the casing comprises a first half casing , a second half casing fitted to the first half casing , a fastening ring and a bottom cover ; the first half casing and the second half casing are butted ; the fastening ring is provided on the top ends of the first half casing and the second half casing so as to fasten the both ; and the bottom cover is provided at the bottoms of the both . the first half casing , the second half casing , the fastening ring and the bottom cover are clamped and fixedly connected with each other to form a whole casing so that the whole wall thickness of the casing is uniform , thus improving injection moulding processes , reducing the difficulty in manufacturing a mould , saving plastic resources , and facilitating installation and disassembly .