GB997060A - Piston powder actuated tool - Google Patents

Abstract

997,060. Cartridge-actuated tools. OMANK INDUSTRIES Inc. Jan. 10, 1964 [Jan. 11, 1963], No. 1254/64. Heading B4C. A cartridge-actuated tool comprises a piston assembly 52 freely removable from the breech end of a barrel 31 after the breech mechanism 11 has been moved away, and a carrier means 50, 51 adapted to frictionally engage a captive piston 67 of the assembly in order to withdraw the latter from the barrel. The piston assembly includes a plunger 68 attached to the piston portion 67, which is slidable in a sleeve 51 constituting the carrier means; a cartridgeholder 50 is formed on the sleeve and is provided with a bore 60 for a plastic holder 56 for the cartridge 55. To load the tool the casing 30 is moved forwardly against the action of a spring 35 until the breech mechanism 11, including the handle 17, can be pivoted about a pin 12 to the open position. A fastener having a locating collar 54 is then dropped into the bore of the barrel so that collar 71 engages in receiving portion 72 of the barrel. The sleeve 51, together with the piston assembly is then inserted into the barrel and the breech mechanism closed. In order to fire the tool, the muzzle end of the barrel is pressed against a workpiece thereby compressing the spring 35 as shown in Fig. 2, the rearward movement of the barrel being stopped when a breech block 21 abuts a shoulder 85 formed on a sleeve 20. Upon actuating a trigger 18 a spring-loaded firing pin 23 is released, thereby exploding the cartridge so that the gases drive the piston forwardly. Before the piston 67 reaches the end of its stroke some of the explosive gases pass to the front of the piston, via slots 78 formed in the sleeve 51, into a space 74, thereby providing a cushion which prevents the end 83 of the piston striking a face 73 on the barrel. A muzzle ring 38 may be replaced by a longer one in order to suit a different length of fastener.