Precision quill-type machine tool spindle

Claim 1

IN A PRECISION QUILL-TYPE MACHINE TOOL SPINDLE, THE COMBINATION COMPRISING A HOUSING HAVING A CYLINDRICAL OPENING THERETHROUGH, A SPINDLE HAVING A CYLINDRICAL PORTION EXTENDING THROUGH SAID OPENING, SAID CYLINDRICAL PORTION OF SAID SPINDLE BEING LONGER THAN THE CYINDRICAL OPENING IN SAID HOUSING, MEANS ON SAID SPINDLE FOR ENGAGING SAID SPINDLE TO ROTATE THE SPINDLE AND MOVE THE SPINDLE LONGITUDINALLY OF SAID HOUSING, MEANS AT ONE END OF SAID SPINDLE FOR SUPPORTING A TOOL, SAID HOUSING HAVING AT LEAST TWO LONGITUDINALLY SPACED SETS OF PRESSURE PADS IN THE SURFACE OF SAID CYLINDRICAL OPENING, EACH SAID SET COMPRISING A PLURALITY OF CIRCUMFERENTIALLY SPACED PRESSURE PADS, AN ORIFICE ASSOCIATED WITH EACH PRESSURE PAD AND COMMUNICATING DIRECTLY WITH ITS RESPECTIVE PRESSURE PAD, MEANS FOR SUPPLYING LIQUID UNDER PRESSURE TO EACH SAID ORIFICE, THE SIZES OF SAID ORIFICES BEING SUCH THAT THE PRESSURE OF LIQUID IN THE PADS OF EACH SET OF PADS IS NORMALLY EQUAL, THE RELATIVE DIMENSIONS OF THE SURFACES OF SAID CYLINDRICAL OPENING WHEREIN SAID PADS ARE POSITIONED AND SAID SPINDLE BEING SUCH THAT A PRESSURIZED FILM OF LIQUID FLOWS CONTINUOUSLY BETWEEN THE SURFACES THROUGH THE PRESSURE PADS SO THAT FORCES ON THE SPINDLE ARE BALANCED BY PRESSURE IN THE PADS PROVIDING A SEPARATION OF THE SURFACES AND RETAINING THE SPINDLE IN A PREDETERMINED RADIAL POSITION RELATIVE TO THE HOUSING THROUGHOUT THE ROTATIONAL AND LONGITUDINAL MOVEMENT OF THE SPINDLE RELATIVE TO THE HOUSING.