GB633583A - Improvements in and relating to dies for broaching holes previously bored in workpieces - Google Patents

Abstract

633,583. Trimming-punches; making watch parts. LANGEL, R. Oct. 27, 1947, No. 28677. Convention date, Aug. 8, 1941. [Classes 83 (ii) and 83 (iv)] Previously-bored holes in articles such as watch parts are trimmed by a punch comprising two parts 1, 2, in one of which a bushing 11 surrounds a cylinder 5 provided with a chamber 17 containing oil for the lubrication of the tools 9 and the movable parts of the die, means being provided for feeding oil into the chamber. The part 1 is secured to the table of a press while the part 2 is reciprocated on guide posts 3, 4 and carries the die. The bushing 11, which is slidable and upwardly biassed by means not shown, is prevented from rotating by a pin 19 and carries plates 12, 13 to guide the tools 9. The cylinder 5 is also provided with plates which hold the tools and have holes 20 to allow the oil to pass into a second chamber 21. The chamber 17 is fed through ducts 16, 18 from a reservoir 15 which is provided with a float F. When the part 2 displaces the bushing 11, oil in the chamber 21 is urged towards the tools and the engaging surfaces of the bushing and the cylinder. In an alternative construction, the part 1 carries the die while the part 2 carries the tools. In this case, the bushing 11 has its movement limited by screws having plain shank portions passing through holes in the flange of the cylinder 5. Oil is fed into a duct in the part 2 and distributed to the chamber 17 and the sliding surfaces by a threearmed cross-bar.