Patent ID: 6371430
Filing Date: 2002-04-16
Classification: B25B,B65H

Abstract:
An automatically adapting vacuum holder for holding a workpiece by suction by the application of a vacuum from a vacuum source, the vacuum holder comprising:(a) a workpiece-bearing member having a workpiece support surface adapted for supporting the workpiece thereon, and (b) a vacuum plumbing system connectable to the vacuum source through a set of at least one vacuum ports, the plumbing system including: (i) a plurality of chambers positioned along one or more directed lines of connection, each line of connection including one of said plurality of chambers directly coupled to and emanating from one of the set of vacuum ports, (ii) a plurality of passageways positioned between any two chambers along any one of said lines of connection for controllably connecting each chamber along a line of connection to the next chamber further from the vacuum source along the line of connection, each of the passageways having a connected state and a disconnected state substantially connecting and substantially not connecting, respectively, the two chambers on either side thereof, and (iii) a plurality of vacuum bores each extending from the workpiece support surface of the workpiece-bearing member to a corresponding chamber to define a suction opening on the support surface and configured to be substantially covered when the workpiece is placed thereon, â€ƒeach chamber either directly connectable to the vacuum source or capable of being connected to the vacuum source via the passageways along one of the directed lines of connection, â€ƒeach of the passageways from any particular chamber to the next chamber along any of the particular chamber's directed lines of connection being: biased to be in the disconnected state to the next chamber along any of the particular chamber's lines of connection when the vacuum is not applied, configured to remain in the disconnected state to the next chamber along any of the particular chamber's lines of connection if the suction opening of each of the vacuum bores of the particular chamber is not covered by the workpiece, and configured to be in the connect state to the next chamber along any of the particular chamber's lines of connection when the vacuum plumbing system is connected to the vacuum source and the vacuum is applied and when the workpiece is placed on the surface so that the workpiece substantially covers the one or more suction openings of the particular chamber and all the suction openings of the chambers closer to the vacuum source along any of the particular chamber's line of connection, â€ƒsuch that the vacuum holder automatically adapts to the size of the workpiece by automatically limiting the number of uncovered suction openings to which the vacuum source is coupled when the vacuum source is connected to the vacuum plumbing system and the vacuum is applied.