GB1267693A - Improvements in or relating to explosive-actuated tools for driving studs, nails or other anchoring members into hard materials - Google Patents

Abstract

1,267,693. Cartridge actuated fastener driving tools. BIRMINGHAM SMALL ARMS CO. Ltd. 24 Aug., 1970 [21 Aug., 1969], No. 41667/69. Heading B4C. A cartridge actuated fastener driving tool of the kind including a fastener driving piston comprises a cartridge magazine holder pivotally mounted in the tool, means for firing a cartridge, and means for ejecting a spent cartridge from a cartridge chamber, the tool being so arranged that in a first or normal position, the holder is aligned with the chamber. When a firing pin of the firing means is aligned with the chamber to permit firing of a cartridge the holder is located in a second position and when the ejecting means is operated the holder is moved to a third position. As illustrated in Figs. 1 and 3 a magazine 10 is held within holder 7 and the holder is normally held in its first position by springs 18, 74. Application of the muzzle end of the tool to a workpiece effects depression of rod 21 and consequential displacement of the holder against bias of spring 18 to the second position (Fig. 2, not shown). The firing pin 8 is then aligned with the cartridge chamber. Depression of trigger 22 about pivot 23 causes clockwise rotation of hammer 25 against bias of spring 27, the hammer being released when catch 28 is disengaged from projection 30 by engagement of stop 31 with a cam surface on the catch. Removal of the tool from the workpiece returns the tool to the condition of Fig. 1. Clockwise rotation of pivoted lever 32 will firstly cause pin 37 to pivot holder towards the Fig. 3 position and then cause pivoting of the holder to the Fig. 3 position and downward displacement by pin 35 of an ejector 34. The ejected cartridge falls out the bottom of handle 2. The polyurethane foam buffer 15 or a spring (not shown) will return the piston 12 after a fastener driving operation. In an alternative embodiment (Fig. 6, not shown) the firing pin is carried by the workpiece engaging rod (41). In the embodiment of Fig. 7 the firing pin 44 is carried by trigger 45 which is slidable substantially parallel to the piston axis. A catch 53 pivotally mounted on the trigger engages in a recess 54 to prevent trigger movement. A workpiece abutting rod 55 cams the catch 53 from the recess to permit trigger movement when the muzzle end of the tool is pressed against a workpiece. In the embodiment of Fig. 8 the trigger is integral with the magazine holder and the firing pin is carried thereby. A spring biased pivoted catch 62 has a free end portion normally engaged in groove 64. The end 65 of the groove prevents rotation of the trigger/holder combination into the second position unless the tool is pressed against a workpiece in which case the rear end of rod 66 will extend into the groove 64 and act to cam the catch 62 past the end 65. The embodiments of Figs. 7 and 8 may include cartridge ejection means similar to that of the embodiment of Figs. 1 and 3.