GB1355321A - Self-propelled lifting vehicle - Google Patents

Abstract

1355321 Vehicles with lifting platforms H H DENIER 2] April 1971 10411/71 Heading B8H A self-propelled lifting vehicle comprises a platform 16 connected by means of a lazy tongs linkage only one side of which is shown to a wheeled chassis 1 for vertical movement relative thereto, a motor 3 for driving the wheels 2 of the chassis and an hydraulic ram 12 for use in steering the wheels 5 being mounted on the chassis 1 and operable from a push button control panel 64 mounted on the platform 16, on which control panel there are further push buttons for actuating a first set of hydraulic rams (39), Fig. 9 (not shown), mounted on the chassis 1 for shifting the lazy tongs linkage initially from a collapsed position to a partially erected position and a second set of hydraulic rams 45 which complete the raising of the lazy tongs to a fully extended condition, Fig. 7. At the lower end of the lazy tongs the ends 24 of one set of the bars forming the said tonga are connected to the chassis for pivotal movement about studs 23 while the lower ends 19a of their companion bars have rollers 30a which facilitate their sliding movement along the chassis 1 during raising and lowering of the lazy tongs whose upper bars are connected to the platform 16 in a similar manner. An hydraulic system is depicted in Fig. 15 (not shown) in which there is a valve (45c) connected between a reservoir for hydraulic fluid (73) and the above-mentioned hydraulic rams for elevating and lowering the platform there being a second valve (15a) connected between the said reservoir and the ram 12 which is used for steering the chassis, and two further valves (60d, 60g) connected each to one of a pair of rams (60) (60a) which each control an outrigger 52 mounted on each side of the chassis 1 for movement in a vertical plane between raised (inoperative) positions and lowered (operative) positions. When it is desired to elevate the platform 16 a push button (88), Fig. 11 (not shown), on the control panel 64 is actuated, and thus the valve (45c) is actuated which causes hydraulic fluid to flow into a main supply line (39c) and then through branch connections into the first hydraulic rams (39) and second rams 45, the rams (39) reacting to the fluid in advance of the rams 45. Other push buttons on the same panel 64 actuate the valves which control the outriggers, and a first lever (65) thereon controls the steering ram 12 while a second lever (66) thereon controls the drive motor 3.