US Patent 11419442 Tray assembly

A tray includes a first tray configured to be fixedly mounted to a robot; a second tray provided above the first tray and configured to be rotatably coupled to the first tray; and at least one pad assembly positioned between the first tray and the second tray. Each of the at least one pad assembly includes at least one rolling member provided in a direction toward the first tray and an elastic member having at least one end fixedly connected to an interior of the at least one pad assembly. The at least one pad assembly is coupled to the second tray and is mounted to be rotatable relative to the first tray. When the second tray is rotated relative to the first tray, the second tray is configured to be returned to its original position by virtue of a restoring force of an elastic member of the pad assembly.