GB668552A - Improvements relating to grabs - Google Patents

Abstract

668,552. Grabs for handling material. WESTWOOD & CO., Ltd., J., and CAULFIELD, W. J. Feb. 22, 1950. [Feb. 24, 1949] No. 5121/49. Class 78 (iv). Tail portions on the claw-like blades of a grab engage horns on the upper beam when the grab is fully open and return the blades from an off-centre position to which they are permitted to move, when engaging an irregular load, by universal joints between the lower beam and the blades and between the upper beam and the usual links joining the upper beam to the blades. In the construction illustrated the blades 1 are hinged about horizontal pins 9 (Fig. 5) to brackets 7 mounted for limited swinging movement on the lower beam 2 by hinges whose vertical pins 8 lie immediately inside the periphery of the beam. A simple horizontal hinge 12a joins each blade to its operating link 12 which is hinged about a horizontal pin 16, Fig. 3, to a bracket 14 connected to the upper beam 13 by vertical hinge-pins 15 supported outside the periphery of the upper beam proper. The grab is opened and closed by relative movement of the upper and lower beams effected by the usual purchase gear disposed between them. The opening movement of the grab is limited by tail portions 17 of the blades which also serve, by engaging horns 18 on the lower beam 2, to centre any blades which have swung laterally. According to the Provisional Specification, ball joints may be used instead of the universal joints described.