GB572348A - Improvements in or relating to safety devices for presses, punches and like machines - Google Patents

Abstract

572,348. Machinery safety devices. FRENCH & SONS, Ltd., T., and WILDE, C. E. Nov. 16, 1943, No. 19067. [Class 80 (iv)] Relates to safety devices for presses, punches and like machines in which a feeler member movable with and in advance of the ram, punch &c. is adapted, when obstructed by an operator's hand, to produce relative movement between the ram and feeler to actuate means such as a catch-pawl to check the movement of the ram. According to the invention, the feeler member and stop means are resiliently coupled by means arranged positively to move the stop means. The ram b carries a cross-head a from each end of which depends a bracket d located near a rack e secured to the side of the ram guides c. In each bracket is pivotally mounted a lever g movable between stops h, i and adapted to act on a pivoted pawl f so as to bring it into engagement with a rack e. Carried from the end of each lever by rods j is a feeler k in the form of a plate closely surrounding the tool or ram b. The rods j are guided at l and pass loosely through the levers g, a spring m being interposed between each lever and a nut on the rod. Obstruction of feeler k tilts the levers g to throw the pawls into engagement with the racks. In a modification, the levers g may actuate a check valve of a hydraulic system wherein the cylinders would be on the cross-head a and the pistons connected to brackets fixed to the guides c. Means may be provided, e.g. a clutch or switch, to cut off the power when the movement of the ram is checked. Visual or audible indication means may be provided to indicate when the safety device has been brought into operation.