Patent ID: 6174113
Filing Date: 2001-01-16
Classification: B23Q,G06K,H05K,Y10T

Abstract:
A machining apparatus for machining a cavity in a smart card, said machining apparatus comprising:a card holder for holding the card;a milling tool;a drive mechanism connected to the milling tool, the drive mechanism rotating and feeding the milling tool;a control circuit couple to the drive mechanism, the control circuit controlling the drive mechanism;an electromagnetic field generator located in the environment of where the card is held by the card holder; anda detector coupled to the control circuit, the detector detecting a variation in an electric potential of the milling tool and delivering a reference signal to the control circuit when the variation exceeds a predetermined value,wherein the control circuit controls the drive mechanism such that when the reference signal is received from the detector to indicated a reference position, the milling tool is made to continue to penetrate the card for a predetermined travel from the reference position so as to reach a machining position, andthe control circuit has an input that receives a second predetermined value corresponding to the predetermined travel from the reference position.