of the gap created when the heat detection fuse 60 is melted therefore the adjustment plate 40 fails to support the springs 36 and 38 since the adjustment bolt 45 is relaxed whereby the locking action is automatically released fig1 and 13 show an additional embodiment of the present invention for connecting the rotation body 6 and the support body 10 a locking frame 70 is formed around the top of the rotation body 6 39 and connects with case 74 and frame 72 to the support body 10 39 so that the rotation body 6 39 may be rotated from the support body 10 39 the locking balls 12 39 and 14 39 installed in the rotation body 6 39 also move around guide grooves 16 39 and 18 39 and locking grooves 20 39 and 22 39 of the support body 10 39 for performing the locking function the lock has the function of a fireproof door by installing the heat detection fuse 60 39 with the adjustment bolt 45 39 which connects with the adjustment plate 40 39 element 76 is a wearproof plate 78 a door 80 and 80 39 heat detection fuse holes 82 and 82 39 fuse openings and 84 a wall furthermore 4 39 is an arm 32.