Patent ID: 8597200

Claim:
A biopsy device, comprising: a coring cannula having a longitudinal axis and a shaft centered on the axis, the coring cannula rotatable about and movable along the axis, the coring cannula being coupled to the housing such that rotational movement of the coring cannula about the axis results in linear movement of the coring cannula along the axis; a stylet having a tip containing at least one blade and a central passage; a motor assembly coupled to the coring cannula for controllably rotating and simultaneously advancing the cannula; a circuit electrically coupled to the motor assembly; a forward/reverse switch electrically coupled to the circuit for controlling the direction of movement of the cannula; and, a control trigger electrically coupled to the circuit, the circuit for responsively controlling rotation of the cannula as a function of the forward/reverse switch and actuation of the control trigger, wherein the circuit is a variable speed circuit configured to control rotational speed of the cannula as a function of a level of actuation of the control trigger, the circuit having a predetermined speed range.