GB884858A - Machine for making screw blanks - Google Patents

Abstract

884,858. Forging socket-head screws. TEXTRON Inc. Jan. 16, 1959 [Jan. 24, 1958], No. 1632/59. Class 83 (4). In the manufacture of a socket-head screw blank by driving a pin punch 39, Fig. 3, into the head 42 of the blank whilst enclosed in a die 15, the blank is positively stripped from the punch after its withdrawal from the die. Blanks cut from rod or wire stock are coldheaded in two operations in a double blow header having a single fixed die 15 with an ejector pin 17, and a reciprocating gate 12, Fig. 1, mounting a transversely movable slider 51 carrying first and second heading punches 20, 30. Punch 20 has a spring-loaded centre pin 24 for holding the blank in the die upon withdrawal of the punch after the preliminary heading. Punch 30 which performs the final heading includes a sleeve 41 surrounding the rigidly mounted socketting punch 39 and is slidably mounted in its holder 31 being biased forwardly by springs 34 surrounding stripper pins 35 engaging a slide member 50 actuated by a bell-crank lever 47. After forming the socket, the pin 40 with the blank adhering thereto is withdrawn from die 15, and subsequently the slider 51 is moved transversely to the right whereby bell-crank 47 engages a stop 56 and is pivoted anti-clockwise to force slider 50 with pins 35 and punch 30 forwardly relatively to the socketting punch 39 to strip the blank therefrom.