Compressed air cooled spindle unit

Claim 1

AN AIR COOLED MOTORIZED SPINDLE UNIT, INCLUDING, IN COMBINATION, A HOUSING HAVING A MOTOR MOUNTING COMPARTMENT THEREWITH; A MOTOR MOUNTED IN SAID COMPARTMENT, AND INCLUDING A DRIVEN MOTOR SHAFT EXTENDING THROUGH SAID COMPARTMENT; BEARING ASSEMBLIES MOUNTED IN SAID HOUSING IN AXIAL ALIGNMENT WITH SAID MOTOR SHAFT; A SPINDLE ROTATABLY MOUNTED IN SAID BEARING ASSEMBLIES AND BEING OPERATIVELY COUPLED AT ONE END THEREOF WITH THE ADJACENT END OF SAID MOTOR SHAFT; SAID MOTOR MOUNTING COMPARTMENT BEING SUBSTANTIALLY CLOSEDOFF FROM SAID BEARING ASSEMBLIES AND THE LENGTH OF THE SPINDLE EXTENDING THEREACROSS AND THEREBETWEEN; MEANS FOR SUPPLYING A LUBRICANT TO SAID SPINDLE AND SAID BEARING ASSEMBLIES; A COOLING JACKET MOUNTED IN SAID HOUSING AROUND AND ALONG SAID MOTOR IN HEAT TRANSFER RELATION THEREWITH; SAID COOLING JACKET AND SAID HOUSING BEING FORMED TO PROVIDE A COOLING AIR CIRCULATING CHAMBER THEREBETWEEN AROUND SAID MOTOR IN HEAT EXCHANGE RELATION WITH SAID COOLING JACKET; MEANS SEALING SAID COOLING AIR CIRCULATING CHAMBER AGAINST ESCAPE OF AIR THEREFROM TO SAID MOTOR; AND SAID SPINDLE UNIT HAVING AN AIR INLET PASSAGE INTO AND AN AIR OUTLET PASSAGE FROM SAID COOLING AIR CIRCULATING CHAMBER.