GB1070131A - Improvements in cartridge-operated tools - Google Patents

Abstract

1,070,131. Cartridge-actuated tools. BURRA ENGINEERING CO. Ltd. Dec. 17, 1965 [Sept. 18, 1964; Sept. 17, 1965], Nos. 35971/64 and 39867/65. Heading B4C. A cartridge-actuated tool for driving fasteners such as pins or bolts into structures comprises a barrel 7 mounted in a housing 6 and an operating means 17, 18, 19 adapted, when the muzzle of tool is pressed against a surface, to advance a magazine 8 through the housing in a stepwise manner. The barrel 7 is slidable in the housing 6 and is formed with two arms 17, 18 between which the magazine slides, the housing being provided with apertures to permit such movement of the magazine. The magazine which may be of light alloy or synthetic plastics material is formed with two rows of cartridgechambers (65, 5) adapted to be brought alternately into alignment with one or other of a pair of bores 9 in the barrel. A firing pin 36 is mounted in a block (30, Fig. 2) loaded by springs 37, the pin having a pair of projections 36a. A hammer pin 41 is mounted in a block 38a, 38b, fixed in the housing, the pin being arranged to co-operate with a sear 52 carried by a leafspring 50. In operation, a loaded magazine is inserted into the tool until the end one of a row of teeth (73, Fig. 2) engages with a pawl 23 on the arm 18 of the barrel. Upon pressing the muzzle against a surface, the barrel moves thereby causing the pawl 23 to disengage the tooth and causing a second pawl 19 on the arm 17 of the barrel to engage the end one of a row of teeth (69) thereby indexing the magazine; the end cartridge-chamber 65 of the upper row is then brought into alignment with the upper bore 9 in the barrel. During the movement of the barrel the hammer pin 41 is cocked by the sear being moved rearwardly by the arms 17, 18. When a trigger 62 is depressed a lever 55 abuts the leaf-spring 51 thereby releasing the hammer pin so that it strikes the firing pin 36. A fastener is then driven from the magazine through the barrel, the exhaust gases passing out of the barrel via ports 10; in a modification the magazine may be formed with a single row or more than two rows of cartridge chambers. A splinter guard 12 is provided and may be formed with locating means for conduit clips or other parts adapted to be secured by the fasteners; the parts may be held in the guard by resilient or magnetic jaw or chucks.