Patent GB-852736-A (GB)
Title: Improvements in or relating to fastener inserting apparatuses
IPC: B25C1/04
Filed: 1957-04-15
Abstract: 852,736. Fastener inserting machines. BRITISH UNITED SHOE MACHINERY CO. Ltd. April 15, 1957 [April 16, 1956], No. 12174/57. Class 89(3) A fastener supplying assembly suitable for use in a fastener inserting apparatus including a readily movable hand'held fastener inserting tool connected by flexible pipes to the supply assembly, comprises a downwardly extending raceway, a separating mechanism adjacent the lower end of the raceway, a hopper adapted to be moved up and down to supply fasteners to the raceway in which they provide an ordered array, a signal pipe and a delivery pipe, the arrangement being such that in response to a signal in the signal pipe, the separating mechanism separates a fastener from the ordered array and a fastener is blown along the delivery pipe to the fastener inserting tool. In the exemplified embodiment, a nail inserting gun 150, Figs. 12 and 16, is operated by depressing a finger button 221 to open a valve 218 to admit compressed air from a flexible line 214 and supply pipe 213 to an air motor 155 having a hammer 163 which imparts a rapid succession of blows to the driver 164 to drive into the workpiece a nail already positioned in the chuck 168 of the gun. Whilst the button 221 is depressed, a signal pipe 231 receives compressed air through a passage in the valve 218 and delivers it to a bore 205 in a valve block 204 causing movement of a valve piston 210 against a compression spring 220 to allow passage of compressed air from the supply pipe 213 through one way valves 238, 243 respectively into compressed air reservoirs 2, 3 in the form of tubular frame members, Fig. 1, of the machine. From the reservoir 3, air passes through a needle valve 89 to an air motor 60 which causes a nail hopper 17 to be oscillated up and down about pivots at its forward end 5, the operation of the air motor 60 being maintained, until the air in the reservoir 3 is expended, for a period after the valve piston 210 is returned to the closed position by the spring 220 upon release of the push button 221 of the gun 150. This assists in obtaining a desired rate of supply of nails from the hopper 17. Simultaneously with the supply of compressed air to the reservoirs 2, 3, compressed air flows along a pipeline 244 to branches 135, 246. Compressed air from the branch 135 enters a bore 133 in a separator valve 124 thereby displacing a piston 136 to align a passage 133 therein with a passage 141 containing a nail, thereby allowing the nail to fall through to a nail delivery pipe 151. Compressed air from the branch 246 flows into a bore 107 of a block 106 and displaces a nail picker 111 so that a slot 119 in the nail picker is brought opposite the lower end of a slot 96 in a raceway 91 which receives nails from the hopper 17, and a nail from the raceway enters the slot 119. When the supply of compressed air to the branches 135, 246 is cut off upon the return movement of the valve piston 210 consequent upon release of the push button 221 of the gun 150, the piston 136 and the nail picker 111 are returned to their first position, thereby placing the reservoir 2 in communication with the nail delivery pipe 151 via pipe 147 and passages 146, 142, so that the nail in the delivery pipe 151 is blown into the chuck 168 of the gun 150, and also causing the nail in the slot 119 of the picker 111 to be dropped, via a gate 124 and funnel 143 into the passage 141 where it rests on the piston 136. A nail slot 31, Fig. 6, in the bottom of the hopper 17, is defined by a fixed bar 39 and a laterally movable, outwardly spring urged bar 32. The raceway 91 is formed by a fixed wall 92, Fig. 10, and a laterally adjustable wall 93. The forward ends of the bars 32, 39 have projections 101, 102 and the upper ends of the walls 92, 93 of the raceway have lugs 103, 104 which engage outside the projections 101, 102. Cams 41, 97 pivoted on the base of the hopper and to the support 56 respectively, engage the bar 32 and wall 93, and are adjustable to set the spacing of the nail slot 31 and raceway slot 96 to a width corresponding to the size of nails to be inserted. A plate 44, arranged to swing towards and away from the front wall 5 during oscillation of the hopper 17, is provided with a lower edge 48 which just clears the heads of nails correctly oriented in the slot 31. The gun 150 is provided with a driver 164, Fig. 13, held within a forwardly extending cylindrical portion 161 by means of a spiral spring 181 screwed over the portion 161. The nail chuck 168 comprises a nail chamber 187, Fig. 18, in communication with a bore 167 which receives the driver 164. A flexible nail delivery pipe 193 communicates with the chamber 187 and is connected at its other end to the pistol grip 184 of the gun. The nail chuck 168 is supported by one end of a tubular member 169 which at the other end is slidably mounted in the body member 153 of the gun. The tube 169 has a slot 172 which slides over a pin 173, and a spring 175 in the tube, by acting between the pin 173 and a cap 177 screwed on to the tube 169, urges the tube in a forward direction. The cap 177 can be unscrewed to permit the tube 169 to be drawn forwardly so that the chuck can be moved out of engagement with the driver 164 to allow removal of the driver by unscrewing the spring 181 from the portion 161. Two resilient coacting nail gripping jaws 188 are secured to the forward end of the chuck 168 by screws 191: Two plate elements 197, each provided with two forwardly extending spurs 202 adapted to engage the workpiece, are detachably secured against opposite faces of the chuck 168. Specifications 768;816 and 780,310 are referred to.