Abstract: In the process or internally grinding bores with the aid of a slightly conical grinding wheel (15) in a computer controlled manner, the rotational axis (14) of the grinding wheel is adjusted to a small angle (.alpha.) in relation to the rotational axis (3a) of the workpiece (5). The grinding wheel is sharpened along a generatrix which lies opposite the generatrix of the wheel when the wheel is in rough grinding engagement with the bore. The rough grinding operation is carried out at a feed pressure such that twice this angle (i.e. 2(.alpha.) is levelled-out or eliminated and the respective generatrices of the wheel and the bore will substantially coincide. The fine grinding phase of the grinding operation is carried out with substantially coinciding bore and grinding wheel generatrices along an opposite bore generatrix in relation to the rough grinding engagement location. The invention also relates to a grinding machine for carrying out the method.

Abstract: For dressing a rotating grinding wheel which grinds a workpiece held in a chuck, there is mounted on an extension of the chuck, an annular dressing tool having an inner lining of diamond, for example. The dressing annular is accurately centered relative to the workpiece. The grinding wheel is moved through the short distance between the workpiece and the dressing annulus.

Abstract: A grinding spindle holder accommodates two or more grinding spindles and is mounted on, or adapted to be fitted to a feed slide of a grinding machine. The spindle holder has a stationary base part and a movable part which accommodates the grinding spindles and which can be rotatably stepped between given terminal positions by swinging the movable holder part about a shaft extending parallel with the spindle axes, for consecutive movement of the spindles to a grinding position for engagement with a workpiece in one and the same chuck position. The movable holder part can be swung by means of a working piston-cylinder device between two stop abutments located on the base part of the holder, of which stop abutments at least one can be adjusted in a manner to accurately determine the position of a relevant grinding spindle in the grinding position. The spindle holder is also provided with means for damping the swinging movement of the movable holder part towards respective stop abutments.