Abstract: Apparatus and method are disclosed for supporting and transporting a multiplicity of workpieces during a process such as a batch-type vacuum coating process. The workpieces are placed in two stacks adjacent to process equipment inside a sealable chamber, and means are provided for moving substrates within each stack and between the stacks. Preferably, workpieces are successively conveyed from the top of one stack, through the process, to the top of the other stack, and simultaneously from the bottom of the second stack to the bottom of the first stack. The workpieces in the first stack are raised so that successive workpieces are presented at the top of the first stack. Similarly, the workpieces in the second stack are lowered to present successive workpieces at the bottom. Workpieces may be circulated through the stacks as many times as desired and may be processed one or more times during a single circuit.

Abstract: An elongated gate-type valve is pivotally mounted within vacuum coating apparatus of the multiple-chamber, in-line type, and is operated to vacuum seal an access slot interconnecting vacuum chambers. An actuator for opening and closing the slot valve is connected through transversely spaced thrust links, the actuator ends of which have guide wheels, respectively, that are movable within restraining guide channels for confining the actuator ends to linear, vertical movement. An increasingly large closing and sealing force is applied to the valve, especially during final closure thereof, due to an increasing mechanical advantage of the actuator and thrust link arrangement for valve closing.