GB191424252A - Improvements in Jacks Operated by Water or Other Liquid under Pressure for Tipping over the Tumbler or Bridge of Motor Lorries and the like. - Google Patents

Abstract

24,252. Dewald, C. Dec. 18. Jacks. - Hydraulic apparatus for tipping the body of a motor tip-wagon comprises an oscillating cylinder mounted upon hollow trunnions in communication with fixed supply and exhaust pipes, the cylinder having a piston between which and the top of the cylinder fluid is trapped at the end of the stroke so as to transmit jerks to the body as the pump continues working, to facilitate discharge of the load. A cylinder 6 is mounted on hollow trunnions 9, 10 rotating in bearings 11, 12 on the chassis, the outer ends of the trunnions rotating in members 16, 20 having annular spaces in communication with axial bores 13, 19 in the trunnions. The bore 13 leads to an annular space 14 which communicates with the interior of the cylinder through holes 15. The bore 19 is connected to the lower end of the cylinder by a pipe 22. A plunger, having a central part 1 of reduced diameter, is pivoted at 5 to the wagon body which is pivoted to the chassis at its rear end. To tip the body, pressure fluid from a pump is led through a pipe 30, Fig. 2, past a slide valve 25 and orifice 26, and through a fixed pipe 28 to the member 20, and thence to the cylinder, the valve 25 being moved to the right from the position shown. At the end of its stroke, the plunger uncovers the holes 15, and any further fluid supplied is returned to the reservoir through the bore 15 and a pipe 29. Fluid is trapped between the cap 2 of the plunger and the packing-ring 7 of the cylinder, to act as a stop, and transmit the impulses of the pump to the body so as to make the load slide. To restore the body to its normal position, the valve 25 is moved into the position shown, and the water in the cylinder runs back to the reservoir through the pipe 28, holes 33, and a pipe 31. A ball valve 27 may be provided for the orifice 26, and the exhaust fluid returned through a restricted passage 32 so as to cushion the return movement of the body, or the body, as it nears its normal position, may act upon the valve 25 so as almost to close the holes 33.