GB852376A - Variable-throw crank mechanism for feeding metal stock to punch presses - Google Patents

Abstract

852,376. Feeding metal strip. LITTELL MACHINE CO., F. J. Feb. 27, 1958, No. 6370/58. Class 83 (4). [Also in Group XXIV] In adjustable crank mechanism for reciprocating a rack 37, Fig. 1, driving the feed-rolls of a punch press, the rack is secured to a member 62 journalled on a collar 57, Fig. 3, which encircles, but is spaced from, a sleeve 51 on a crank-pin or trunnion 45 projecting from the face of a plate 38 mounted on a driving- shaft 21, the collar 57 being radially adjustable relatively to the trunnion 45 by rotation of a remote control wire 103 to effect small adjustments in the stroke of the rack during operation thereof. The rack 37 operates through a one-way clutch 33 to rotate intermittently the rolls 23, 24 feeding metal strip to the press. The radial position of the collar 57 is determined by pins 65, 66 whose inner ends engage an inclined portion of an axially-movable adjusting-pin 50, the pin having cylindrical end-members slidable in a bore in the trunnion 45. The pin 50 is coupled by a universal link to a plunger 90 in screw-thread engagement with the shank of a bevel gear 81 rotatable in a housing 80 carried by the member 62. The gear 81 is engaged by a pinion 110 coupled to a flexible control wire 103 rotatable by a hand wheel 104, Fig. 1. Rotation of the wheel 104 shifts the threaded plunger 90 and pin 50 to cause radial displacement of the pins 65, 66 supporting the collar 57, the collar being thus adjusted between concentric and eccentric positions relatively to the trunnion 45 so that the stroke of the rack 37, and thus the rotation of the feed rolls 24, 25, may be adjusted while the press is operating. In order to avoid undue loading of the pins 65, 66, Fig. 5, supporting the collar 57, lateral forces between the collar 57 and trunnion 45 are absorbed by a pair of thrustplates 74, 75 mounted in grooves in the collar 57 and engaging flattened sides of the sleeve 51 on the trunnion, the thrust-plates being substantially parallel to the rack. The trunnion 45 is itself mounted for radial adjustment across the plate 38, having a wedge-shaped head 46 engaging an undercut diametral groove 40, Fig. 2, in the face of the plate, adjustment being effected, when the plate is at rest, by rotation of a screw 41 threadedly engaging the head 46. The trunnion is locked in adjusted position by a nut 53 thereon which, acting through the sleeve 51, tightens the head 46 against the undercut sides of the groove 40.