Patent GB-711241-A (GB)
Title: Improvements in and relating to elevating apparatus
IPC: B60P1/44
Filed: 1951-12-03
Abstract: 711,241. Vehicle fittings; load handling appliances. ANTHONY CO. Dec. 3, 1952 [Dec. 3, 1951], No. 28280/51. Classes 78 (3) and 78 (4) Apparatus for raising and lowering loads in which-one arm or one set of arms carrying the platform for the loads is extensible has a hydraulic cylinder pivoted to the support to which the arms are pivoted and connected with the arm or set of arms and capable of transmitting power in opposite directions to. the extensible portion of the arm or set of arms to raise and turn up the platform. A tail-gate 45; Fig. 3, is pivotally connected at 50 to a pair, of telescopic members 9, 10 pivoted at 11 to a bracket secured to a vehicle. The piston rod 18 of a hydraulic cylinder 19 is mounted on a pivot 20 secured to pivoted extensions of the bracket and is connected to a cross head 17 trunnioned in supports. The hydraulic cylinder is controlled by a fourway valve 55 operated by a lever 59 connected by Bowd.en cable 60, with a lever on a shaft 86 rotated by a lever 97. The valve has connections with the pump and the reservoir and with either side of the piston in the hydraulic cylinder. The four positions of the lever 97 effect raising the platform or rotation from the vertical position to the horizontal position, lowering or rotation from the horizontal to the vertical position with the platform latched, holding in the horizontal position and latch disengagement. The valve is operated, so that for raising the platform and for lowering fluid flows into the one or other end of the cylinder and ii the platform is latched when horizontal so that it cannot be lowered, then the platform can be rotated to the vertical position by extending the telescopic members 9. 10. The tail-gate is held in its raised horizontal position by a pair of latches 40 mounted on a pair of arms 37 pivoted at 38 to the bracket and at 49 to the platform. The latches engage the cross pins 90 of a pair of hooks 85 mounted on a sleeve 87 of the shaft 86. The hooks are normally prevented from engaging the latches by a pivoted projection 94 on a hook urged clockwise by a torsion spring to engage an abutment 44 on a catch, the hooks being spring urged against a stop 93 to engaging position. When the platform is raised the projection 94 is removed from the abutment 44 and the hooks move into engagement. To disengage the latches the shaft is rotated and an abutment 96 on the hub of a lock releases the latches. The telescopic members 9, 10 have also a holding member to retain them in the extended position when the platform is vertical. The member comprises a cylinder 23 mounted an the pivot 11 and having a rod 34 mounted on a support for the member 9. The cylinder 23 has two shoulders 24, 25 and an outer sleeve 28 urged by a spring 29 to one end of the cylinder and enclosing ball bearing 27 engaging a groove in the rod and apertures in the cylinder. The sleeve has a connection with the wire 81 of a Bowden mechanism also connected to the lever 85 on the shaft 86, by rotating the shaft the sleeve 28 is moved to allow the ball bearings to move into a recess 32 in the sleeve to allow free movement of the rod within the cylinder 23 and so allow the telescopic members 9, 10 to retract. This holding means may be replaced by a hydraulic piston and cylinder connected to cylinder 18 through a ball valve operated by a cam on a controlling lever of the valve 55 connected to the Bowden mechanism 60. The tail-gate is cushioned in the vertical position by adjustable rubber buffers 51. Specification 580,767 is referred to.