Patent GB-557511-A (GB)
Title: A machine for welding sewing-machine needles
IPC: B23K11/00
Filed: 1941-08-20
Abstract: 557,511. Making sewing-machine needles. RAINVILLE, O. J. Aug. 20, 1941, No. 10595, [Classes 83 (ii) and 83 (iv)] Welding.-A machine for welding a resilient thread guide to the flattened side of the shank of a sewing- machine needle blank comprises a rotatable drum provided with needle blank supports, means to rotate the blank and hold it with its flattened side away from the drum, means for feeding a wire strand above the blank, a combined carrier and die for cutting the wire to form a thread guide and place it on the flattened side of the shank and means for welding the guide to the shank at the eye end thereof. Needle blanks with mounting hubs 37, Fig. 10, conical necks 39 concaved and flattened at 40 at one side, and one side cut away as at 41 for the reception of the thread guide 42, are received from a shoot 44, Fig. 3, in recesses 35 in an intermittently rotated drum 27. The recesses have entrance depressions 36 so that the blank after welding may be removed from the drum by a resilient arm 149 working in an annular groove 152 in the drum. The drum is rotated by ratchet mechanism 60, 62, 53 from an eccentric 50 on a shaft 49 which is driven by worm gear 48, 47 from a power driven universal connector. Vibratory movement of the drum is prevented by a spring- pressed friction block 33. During rotation of the drum to feed the needle into position for shaft drives through spur gear 31, 77, attachment of the thread guide, the blank is rotated on its axis in order that the flat side may be uppermost. This rotation is effected by a serrated spring-pressed lever 119, Fig. 11, pivoted on one of the fixed arms 24 and engaging the part 37 of the blank and the blank is held in this position by a spring pressed lever 123 engaging the part 40 of the blank. The blanks are positioned axially by a cam bar 118 against which the end 37 of the blank contacts. The drum shaft drives through spur gear 31, 37, worm gear 75, 74 and spur gear 72, 73 a pair of rolls for feeding flattened wire 42a to form the thread guide arm. The upper roll, which is resiliently mounted, is provided with a semicircular groove to receive the round part of the wire. The wire is fed through guides 78, 79 into position over the drum and a thread guide length is cut off and applied to the flat surface of the needle blank by a combined carrier and die 93, 94 in a slide 84 which is reciprocated by an eccentric 113 on the shaft 49. The part 93 cuts off the length and the part 94 is provided with a guide fork 97 for the wire. To the slide 84 is pivoted at 99 a lever 98 which carries at one end a finger 102 for supporting the cut wire during transfer to the needle blank. The lever 98 which is normally moved by a spring 104 to remove the finger 102 from the wire, is provided with a pin 112, which during the up stroke of the slide moves along an inclined surface 107 until it moves past a lever 108 pivoted at 109 and normally pressed by a spring 111 against the guide 106. The pin moves down the bevelled end 110 of the lever 108 during the down stroke of the slide and the finger 102 moves under the wire strand. When the slide reaches its downward position the pin 112 is freed from the lever 108 and the spring 104 disengages the finger 102. Welding is effected between a fixed electrode 126 and an electrode 127 which is carried by a lever 139 pivoted at 130 and connected by a spring 141 to a three-armed lever 131, 132, 133, which is held by a spring 134 in contact with an arm 147 on the shaft 49. The arm 147 moves down the lever arm 132 to effect welding, a member 144 connected by a spring 145 to the lever arm 133 closing the contacts 143 to put in the welding current.