Head for high speed spinner having a vacuum chuck

Claim 1

A head for a vertically oriented, high-speed spinner characterized by a negative pressure chuck comprising: A. a body having a substantially cylindrical peripheral surface and a transverse end surface adapted to be connected to a vertically oriented drive shaft and supported thereby for unidirectional rotation about a vertical axis of rotation including, means defining in the end surface an outwardly facing chamber circumscribed by an annular work-supporting surface adapted to receive in hermetically sealed relation, an impervious work piece; B. means responsive to a rotation of said body about said axis, in the presence of a work piece received by said work-supporting surface, for reducing atmospheric pressure in said chamber including, a plurality of angularly spaced, low-pressure cavities uniformly spaced about the periphery of the body in communicating relation with the peripheral and end surfaces thereof, each cavity being defined by a first surface projected into the body in the plane of the axis at the leading portion of the cavity relative to the direction of rotation thereof, a second surface extended from the peripheral surface of the body along a chord thereof, in a plane paralleling the axis and intersecting said first surface, and a third surface intersecting said first and second surfaces and extended in a plane transversely related to said axis; and C. means for connecting each of said cavities in communicating relation with said vacuum chamber including, a segmented bore having a first segment projected through said second surface and extended to communicate with said chamber.