Simultaneous grinding machine

Abstract

An apparatus for grinding an elongated workpiece having a plurality of outer surfaces of revolution all centered on a common workpiece axis has a frame and means such as a headstock and tailstock for rotating the workpiece about the workpiece axis. Two grinders on the frame diametrally flank the workpiece axis and are displaceable radially of the workpiece axis. They each have a respective set of axially spaced grinding wheels. Actuator means serves for displacing the grinders in respective diametrally opposite directions for engaging the grinding wheels with the surfaces of the rotating workpiece grinder. The axial spacing and dimensions of the wheels correspond to the axial spacing and dimensions of the surfaces such that all the surfaces of the workpiece can be ground simultaneously.

1 . An apparatus for grinding an elongated workpiece having a plurality of outer surfaces of revolution all centered on a common workpiece axis, the apparatus comprising:
 a frame;   means on the frame for rotating the workpiece about the workpiece axis;   two grinders on the frame diametrally flanking the workpiece axis and displaceable radially of the workpiece axis and each having a respective set of axially spaced grinding wheels; and   means for displacing the grinders in respective diametrally opposite directions for engaging the grinding wheels with the surfaces of the rotating workpiece grinder, axial spacing and dimensions of the wheels corresponding to axial spacing and dimensions of the surfaces such that all the surfaces of the workpiece can be ground simultaneously.   
     
     
         2 . The grinding apparatus defined in  claim 1 , wherein for each surface of revolution there is at least one respective grinding wheel. 
     
     
         3 . The grinding apparatus defined in  claim 2 , wherein at least one of the grinding wheels of one of the sets is axially level with one of the grinding wheels of the other set so that the respective surface is engaged by two grinding wheels. 
     
     
         4 . The grinding apparatus defined in  claim 2 , wherein two of the grinding wheels of one of the sets are axially level with two of the grinding wheels of the other set so that two of the surfaces are engaged by two grinding wheels. 
     
     
         5 . The grinding apparatus defined in  claim 2 , wherein each of the grinding wheels of one of the sets is axially level with a respective one of the grinding wheels of the other set so that each of the workpiece surfaces is engaged by two grinding wheels. 
     
     
         6 . The grinding apparatus defined in  claim 2 , wherein at least one of the grinding wheels of each of the sets is axially between two of the grinding wheels of the other of the sets. 
     
     
         7 . The grinding apparatus defined in  claim 1 , wherein the workpiece is a crankshaft and the surfaces include journals between adjacent crankpins and bearing surfaces at ends of the crankshaft, wherein each of the wheels can also engage axially directed faces of flanges carrying the crankpins and flanking the journals. 
     
     
         8 . The grinding apparatus defined in  claim 1 , further comprising:
 a steady rest engageable with the workpiece in a direction perpendicular to a plane defined by the workpiece axis and axes about which the wheels are rotated.   
     
     
         9 . An apparatus for grinding an elongated workpiece having a plurality of outer surfaces of revolution all centered on a common workpiece axis, the apparatus comprising:
 a frame;   means on the frame for rotating the workpiece about the workpiece axis;   two grinders on the frame diametrally flanking the workpiece axis and displaceable radially of the workpiece axis and each having a respective set of axially spaced grinding wheels;   means for displacing the grinders in respective diametrally opposite directions for engaging the grinding wheels with the surfaces of the rotating workpiece grinder, axial spacing and dimensions of the wheels corresponding to axial spacing and dimensions of the surfaces such that all the surfaces of the workpiece can be ground simultaneously; and   a steady rest engageable with the workpiece in a direction perpendicular to a plane defined by the workpiece axis and axes about which the wheels are rotated.   
     
     
         10 . The grinding apparatus defined in  claim 9 , wherein the sets are rotated about respective axes diametrally flanking the workpiece axis in such a direction as to exert tangential forces on the workpiece urging the workpiece against the steady rest.