Abstract: A grinding machine for machining workpieces comprises a machine bed; a workpiece holder comprising a workpiece spindle; at least one grinding spindle comprising a grinding tool for machining; a set of steady rests spaced apart from each other along an axial longitudinal extension of the workpiece, wherein the steady rests are operable in an engagement state and a disengagement state, and wherein the steady rests of the set of steady rests are arranged to engage in the engagement state a workpiece for support, the workpiece being mounted on the workpiece holder; and a control device that is configured to selectively set the steady rests into the engagement state or the disengagement state in such a way that a change between the engagement state and the disengagement state takes place during the machining of the workpiece.

Abstract: Grinding machine for grinding workpieces, in particular cams, a grinding machine holder and a method for grinding cam sets using such a grinding machine. Grinding machine comprising a machine bed, at least one grinding spindle, two grinding wheel holders, on which in each case at least one grinding wheel is arranged and which are arranged in opposite directions to one another in their orientation and are oriented parallel to one another with their longitudinal axes, and two workholding devices which in each case have a work headstock and a steady rest and which are arranged in opposite directions to one another in their orientation and are oriented parallel to one another with their longitudinal axes, wherein each work headstock and the associated steady rest are designed for the arrangement therebetween of a separate work fixture having workpieces to be ground.

Abstract: Grinding machine for grinding workpieces, in particular cams, a grinding machine holder and a method for grinding cam sets using such a grinding machine. Grinding machine comprising a machine bed, at least one grinding spindle, two grinding wheel holders, on which in each case at least one grinding wheel is arranged and which are arranged in opposite directions to one another in their orientation and are oriented parallel to one another with their longitudinal axes, and two workholding devices which in each case have a work headstock and a steady rest and which are arranged in opposite directions to one another in their orientation and are oriented parallel to one another with their longitudinal axes, wherein each work headstock and the associated steady rest are designed for the arrangement therebetween of a separate work fixture having workpieces to be ground.

Abstract: A method of monitoring the wear of a grinding wheel comprises the steps of measuring the force exerted between the wheel and a workpiece, measured normal to the grinding face of the wheel at the point of contact between the wheel and workpiece, and generating a warning signal when the measured force exceeds a predetermined threshold value. A signal indicative of the normal grinding force is obtained by measuring the force exerted by a wheelfeed drive which in use urges the wheel into grinding engagement with the workpiece. Where the wheelfeed drive includes an electrically powered motor, the torque developed by the motor will be proportional to the normal force between the wheel and workpiece. This in turn is proportional to the electrical power drawn by the motor during operation, so an indication of the force between wheel and workpiece is obtained by measuring the power demand made by the motor on its power supply.

Abstract: In a method of grinding a component such as a cam, a reduction in the finish grinding time is achieved by rotating the component through only a single revolution during a final grinding step and controlling the depth of cut and the component speed of rotation during that single revolution, so as to maintain a substantially constant specific metal removal rate during the final grinding step. The headstock velocity can vary between 2 and 20 rpm during a single revolution of the cam during the final grinding step, with the lower speed used for grinding the flanks and the higher speed used during the grinding of the nose and base of the cam. Using a grinding machine having 17.5 kw of available power for rotating the wheel, and cutting with a grinding wheel in the range 80-120 mm diameter typically the depth of cut lies in the range of 0.25 to 0.5 mm.

Abstract: The depth of cut and the headstock velocity of a grinding machine are controlled during the last rotation of finish grinding to maintain a substantially constant load on the grinding wheel spindle drive motor. The depth of cut is kept constant and the component speed of rotation is altered in order to maintain the constant power requirement. If the component profile alters the spindle loading during a single revolution, the component speed is altered from one point to another during each revolution so as to maintain the constant load. Headstock acceleration, deceleration, and velocity are controlled to take into account any variation in contact length between the wheel and component during the rotation of the latter, so that although the metal removal rate may vary slightly around the circumference of the component the power demand on the spindle motor is maintained substantially constant during the whole of the grinding of the component.