GB548955A - Improvements relating to safety guards of power presses and like machines - Google Patents

Abstract

548,955. Machinery guards. PETRIE, D. G. April 28, 1941, No. 5506. [Class 80 (iv)] Relates to guards of power presses and like machines of the kind in which the guard usually in the form of a gate is swingably hinged in a frame which, in the event of the operator's hand being caught in the path of the guard as it returns to its effective position, moves bodily with the guard to carry the operator's hand away from the tool. According to the invention, a thrust-transmitting means is provided between guard and frame which is normally ineffective but is automatically rendered effective to actuate the frame in the event of the operator's hand intercepting the movement of the guard. The guard 1 is hinged at 2 in a frame 3 which itself is hinged to the framework at 4. The guard is divided into two parts 7, 8 hinged at 5, and the part 8 has two tail portions 9, '10 which in normal position upstand from the hinge 5 the parts 7, 8 being then in the same plane. The guard is oscillated by a crank 14 and rod 15 and if it should descend upon the operator's hand, the part 7 will be displaced, Fig. 2, and the tail portions 9, 10 will now abut stops 11, 12 on the frame to drive the latter instead of utilizing the operator's hand for this purpose. In a modification, Fig. 3, the hinge of the guard has a universal joint at 17 and a slot at 18, so that when obstructed it is lifted to bring a lateral projection 19 on the guard in front of a lug 20 on the frame. In further modifications ,1) the lowest bar of the guard is movable therein either in the plane of the guard or transversely thereto (2) the lower part of the gate is adjustable relatively to the upper part by setscrews to vary the width of the gap for the operator's hand.