GB767496A - Stock feed mechanism for a stock working machine, such as a nail making machine - Google Patents

Abstract

767,496. Forging nails. NATIONAL MACHINERY CO. Sept. 18, 1953 [Sept. 19, 1952], No. 33701/55. Divided out of 767,493. Class 83 (4). A stock-feed mechanism for a heading machine, particularly a nail-making machine, having a reciprocating header slide driven by a crank-shaft, comprises an oscillating shaft 45, Fig. 4, driven by the crank-shaft, a reciprocating carriage 56 mounted beneath the oscillating shaft and driven thereby, said carriage being provided with a first gripping block 80 adapted to engage one side of the wire stock, and a lever 78 pivoted to the carriage at 77 and carrying a second gripping block 79 adapted to engage the opposite side of the wire stock, means being provided driven in timed relation to the header slide to move said gripping blocks into gripping contact with the stock whereby the stock is advanced into the machine by the advance of the carriage. The carriage has rollers 71, 72 running on an upper surface 14b, and a rack 55 which is in mesh with a toothed sector 54 secured to the oscillating shaft 45. A bell-crank lever 83 mounted on a pivot 84 carries a roller 81 which bears against the pivoted lever 78. The lever 83 is connected at 87 to a rod 86 carrying a spring 85 which biases the lever 83 in a clockwise direction whereby the roller 81 urges the lever 78 and its block 79 into gripping contact with the stock. A cam 44 mounted on a rotating shaft 43 is adapted to move the lever 83 in a clockwise direction so as to release the block 79 during the return stroke of the carriage 56. A second cam 89 mounted on a spindle which carries a manual operating knob 88 is adapted to move the lever 83 against the spring 85 to release the gripping blocks during the feed-in of the stock. The shaft 43 carries a sprocket 42, Fig. 3c, driven by a chain 40 from the main crank-shaft of the machine. An adjustable crank-pin 49 on the sprocket 42 has mounted thereon a cranked lever 48 the opposite end of which is connected at 48a to a link 47 connected to an arm 46 secured to the oscillating shaft 45. An intermediate point 52 on the lever 48 is connected to a lever 50 mounted on a stationary pivot 51. By this arrangement the oscillating shaft is moved to effect the feed stroke of the carriage 56 during 100 degrees of crank-shaft rotation, and is moved in the opposite direction to effect the return stroke of the carriage during 260 degrees of crank-shaft rotation. The adjustable crank-pin enables the feed movement of the carriage 56 to be varied. The nailmaking machine is of the kind described in Specification 767,493.