GB1099566A - Universal rotary chuck - Google Patents

Abstract

1,099,566. Vacuum chucks. DUNHAM TOOL CO. Inc. March 28, 1966 [April 6, 1965], No. 13659/66. Heading B3D. A rotatable vacuum chuck comprises a rotatable vacuum chamber adapted to be connected to a source of vacuum and rotated about a predetermined axis, plate means which is porous and is adapted to have part of its surface selectively closed off or has a plurality of ports which can be closed by plugs, the plate means being mounted in communication with the chamber, and adjustable stop means arranged about the plate for aligning a workpiece therewith and to restrain the workpiece against radial displacement. The vacuum chamber consists of a network of channels 28 formed in a housing 10 having a threaded shank portion for attachment to a lathe or like machine, the portion having a bore 37 for connecting a source of vacuum to the chamber. In one embodiment, the plate means 11 has a plurality of circles of shouldered ports 15 each of which communicates with the network of channels 28 and can be closed by a shouldered screw having an 0-ring for abutting the shoulder of the post. Each screw also has a passage which, when the screw is partially backed out, connects the port to the source of vacuum. When a workpiece P is placed on the plate 11, those posts not covered by the workpiece are sealed by the screws so that the vacuum only acts at the ports covered by the workpiece. At least three eccentric stops 12 are provided at the periphery of the plate 11 and can be adjusted and secured by screws 34 so as to abut-and retain the workpieee from radial displacement. In an alternative embodiment, the plate is fabricated from a porous material which may be masked with a removable non- porous material having an aperture conforming to the shape of the workpiece in the manner described in Specification 1,069,138, and the edge of the workpieee is abutted by the eccentric stops.