Patent GB-595924-A (GB)
Title: Machine for inserting fastener for binding sheets
IPC: B42B5/10
Filed: 1945-07-09
Abstract: 595,924. Stapling paper sheets. GRINNELL, G. G. July 9, 1945, No. 17470. [Class 89 (iii)] [Also in Group XV] An apparatus for forming coiled wire fasteners 12 and threading them through holes at the edge of a pad 11 of sheets, Fig. 16, in order to bind them together, comprises means for feeding a continuous wire, cutting off lengths and bending them into U-shaped fasteners with straight legs, Fig. 4, means 7a for stacking the formed fasteners and feeding them one at a time beneath a driver, Fig. 2, means for feeding a pad of sheets step-by-step, Fig. 2, and means for drilling a pair of holes in the pad and then driving a fastener and coiling its legs through the drilled holes so that they form a ring embracing the edge of the pad, Fig. 13. Means also are provided for feeding a tape across each side of the pad at the drilling point in order to prevent burring of the outermost sheets of the pad, Fig. 2. A pad to be fastened is supported between adjustable guides 206, 207 on a carriage 62, Fig. 2, which is urged to the left along tracks 215 by a cable and weight, not shown. Step-by-step movement to the left is permitted by a stop slide 82 the nose 83 of which coacts with stop pins 85 placed in holes 84 in the carriage. At each step, two holes are formed near the edge of the pad by drills 63, and a fastener is driven through the holes formed at the previous stop by inserting mechanism 10. The stop slide is reciprocated by a cam lever 87 under control of a treadle, in time with the drilling and inserting operations. When the pad has been operated upon completely, the carriage is returned to the right to an extent determined by stops 113, 116, by an endless cable 93 driven. when tightening pulleys 97, 98 are rocked by a treadle. The drills 63 are rotated continuously and are raised to drill the holes, when a treadle is depressed, by linkage from a crank disk 149 driven by a cam shaft 91. At the same time, a cam roll 154 acts to lower a wooden block, not shown, on to the pad to receive the ends of the drill. The burr-preventing tapes 67, 68 are fed from reels 122 across the line of'drilling by. rolls 124 and a pawl and ratchet 127, 125 driven by the cam shaft. The wire for the fasteners is fed by straightening rolls 16, Fig. 4; and feed rolls 15 to form a supply loop 117 from which fastener lengths are fed by rolls 13 driven by an adjustable friction drive 17. The size' of the loop is kept constant by its action on a switch 120 in circuit with an electro magnet 118 which acts to separate the rolls 15 when necessary. The wire passes to a forming mechanism, Fig. 6, comprising a die 6 across the mouth of which the' wire 1 is fed and a plunger 5 reciprocated by a crank disc. The wire is fed up to an adjustable stop while the plunger is withdrawing, the plunger having a bevelled edge so that the wire can ride over it. A slide 45 operated by a cam slide 49 aligns the wire with the front of the plunger when the latter has withdrawn fully. The fastener length is cut off by a pivoted knife 28 operated by an electromagnet 32, Fig. 4, energised by a rotary conductor. The plunger bends the fastener length into U-form in the die 6 and a bar 54 operated by the slide 49 straightens the cross-bar of the fastener. A catch 55 prevents withdrawal of the fastener by the plunger, and successively-formed fasteners are pushed out of the die on to a raceway 7 which conducts them to the stacking and inserting mechanism. The fasteners form a stack 60, Fig. 13, from which the lowest fastener is moved by a slide 59 up to the driver 76, where its cross bar is held between bevels on the driver and on a spring plunger 187, Fig 16. The fastener is then turned to the vertical position by rock arms 75 which are operated by a latch and a trip rod on the slide 59 and returned by a 'cam surface on the driver 76. The driver is reciprocated by a pitman 182, Fig. 2, and in its descent lowers a presser foot 76a on to the pad. As the fastener is forced down by the driver, its legs are deflected by a pivotally-mounted die 7, Fig. 16, so that they turn back and pass through the holes in the pad. Continued curvature is effected by an anvil 73. The legs may be curved into one or two complete circles, according to the length of the fastener. Near the end of the. travel of the driver, the plunger 187 is stopped by a stop 188 and the bevelled lower end of the driver bends the cross-bar and adjacent portions of the legs of the fastener intoa position substantially tangential to the curved part of the fastener, Fig. 16. The various instrumentalities are driven by electric motors and a cam shaft under control of three treadles. In operation of the machine, when a pad has been placed on the carriage and positioned laterally by stops 213, Fig. 2, depression of the first treadle feeds the carriage one step, feeds the tapes 67, 68, and causes the drills to rise and bore the holes in the pads. The first and second treadles are then depressed together, causing another step of the carriage, a second operation of the drills, and the insertion of a fastener in the holes already bored. When the entire length of the pad has been dealt with, depression for-the third treadle causes driving of the belt 93 to return the carriage to starting position.