Pallet clamping device of stacker crane

The tray clamping and supporting device comprises clamping and supporting mechanisms symmetrically arranged on supporting plates at the front end and the rear end of a bracket, each clamping and supporting mechanism comprises a left swing rod and a right swing rod which are hinged to the supporting plates, the outer ends of the left swing rod and the right swing rod are hinged to a push-pull rod, and the inner ends of the left swing rod and the right swing rod are hinged to a supporting rod. The left swing rod, the right swing rod, the push-pull rod and the supporting rod form a parallelogram connecting rod assembly, the front end or the rear end of the push-pull rod is hinged to a cylinder rod I of a clamping and supporting air cylinder installed on the corresponding supporting plate, the tray is arranged on a cylinder rod II, extending upwards, of a jacking air cylinder above the bracket, and the jacking air cylinder is installed on the portion, below the bracket, of the rack. The cylinder rod II stretches