Patent ID: 7026637

Claim:
A device for measuring runout of a rotating tool, the device comprising: a sensing unit including: a source of coherent electromagnetic radiation, the source being configured to direct the coherent electromagnetic radiation at a surface of a rotating tool having an axis, the surface of the rotating tool being displaced from the axis by a displacement; a sensor configured to receive reflected coherent electromagnetic radiation from the surface of the rotating tool such that the path of the reflected coherent electromagnetic radiation can be determined based upon the received coherent electromagnetic radiation; and a transducer configured to produce a signal representative of the determined path of the reflected coherent electromagnetic radiation; a processor in signal communication with the sensing unit, the processor being configured to receive the signal from the transducer; a memory in signal communication with the processor, the memory containing a program of instructions to be executed by the processor, the program being configured to instruct the processor to receive the signal, to determine a rotation period of the tool, and to record in the memory a digital measurement of instantaneous signal amplitude at a plurality of instants within the rotation period, the instants occurring at a sampling frequency, the digital measurements from the period being arranged in a temporally ordered sequence, the temporally ordered sequences being stored as a pane associated with the rotation period, each pane including an equal number of instants; an averaging filter configured to average corresponding instants across a plurality of panes to generate an averaged pane and an output device in signal communication with the processor and configured to indicate the determined displacement based upon the averaged pane.