Method and relative device for checking the working conditions during the grinding in centerless grinders

A method for checking the working conditions and controlling the machining in centerless grinders including support means having a surface contacting a workpiece being machined, said workpiece being driven in rotation on said surface, comprising:

• generating a first measurement signal responsive to the position of the workpiece surface at a point close to said support means surface;
• generating a second measurement signal responsive to the position of the workpiece surface at the point located diametrically opposite to the preceding point;
• processing said first and second measurement signal to obtain a third measurement signal, responsive to the workpiece diameter;
• utilizing said first measurement signal for automatically controlling adjustments of the position of the support means;
• and
• utilizing said third measurement signal for in-process controlling the machining cycle.

In a centerless plunge-grinding machine including grinding means for grinding workpieces;

• adjustable support means for supporting the workpieces;
• a measuring head including a movable arm for carrying out measurements on a point of the workpiece close to the support means and a position transducer coupled to the movable arm, measuring head being adapted to provide a signal responsive to the position and wear of the support means;
• circuit means connected to said head for receiving said signal;
• and drive means coupled to the circuit means for adjusting the position of the support means, the improvement comprising:
• a second movable arm in said measuring head, said second arm being located to cooperate with a point of the workpiece diametrically opposite to said point close to the support means;
• a second transducer in said measuring head, the second transducer being coupled to the second arm;
• further circuit means connected with the second transducer;
• an adding unit coupled to said circuit means and further circuit means;
• switch means located between said circuit means and adding unit and between said further circuit means and the adding unit;
• an indicating device coupled to the adding unit for providing at least one indication among indications relating to the workpiece diameter, the wear of the support means, the position of the support means and the operating range of either of said first and second transducers;
• and
• a control group coupled to said adding unit for controlling the grinding machine.