GB1388616A - Lift truck - Google Patents

Abstract

1388616 Masted lift truck CLARK EQUIPMENT CO 4 March 1972 10560/74 Divided out of 1388615 Heading B8H [Also in Division F2] Fork lift truck has a telescopic mast 22 with a lifting carriage 26 movable along the inner raisable mast section 32 by a hydraulic lift cylinder 34. A pair of forkes 60 are mounted on a sleeve 74 for movement about a post 76 by a hydraulic molar 120. The posted is mounted to a link 50 pivotally mounted at the opposite end to a cross-head 90 movable in a slot 80 in the carriage and at a point intermediate its ends to a crosshead 92 movable in an arcuate slot 82. A chain 96 extends around the horizontal portion 42 of the carriage and is driven by a hydraulic motor 100 and coupled to the crosshead 92 to move the said crosshead in either direction along the slot 82 to move the post 76 and hence the forks along a straight line transversely of the carriage. A further chain (112), Fig. 7 (not shown) extends around the link 50 and engages sprockets 114, 116 at the respective ends thereof. The sleee 74 is secured to the sprocket 114 to provide a compensating motion of the sleeve whereby as the link moves across the carriage the forks maintain a constant attitude relative to the carriage as they are moved laterally thereof. A pair of rams (130), (132) Fig. 5 (not shown) act on a cross beam (70), which carries the forks, to raise the forks sufficiently to clear the link 50 when the forks are swung over the carriage. A wedge 142 on the forks tilts same backwards as they are raised to retain a load thereon. The vertical portion 40 of the carriage has a series of journalled shafts 152 with a pinion 154 at each end to engage racks 156 extending along the mast section to distribute the load on the carriage between the mast sections. The shafts have crowned splines to receive the internal splinning on a pinion to allow the pinion to tilt relative to the axis of rotation to accommodate mis-alignments of the racks.