The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 06, 1996
Filed:
Jan. 05, 1995
Jerry A Culp, Oshtemo Township, MI (US);
Kevin J Schemansky, Portage, MI (US);
Stryker Corporation, Kalamazoo, MI (US);
Abstract
A powered medical instrument includes a manually operable foot switch coupled to a motor control unit which in turn is coupled to an autoclavable handpiece containing a brushless sensorless electric motor driving a tool. The motor control arrangement includes a control panel through which a user can select a maximum torque value for the motor, and includes a torque limit circuit which limits the motor torque to the torque limit value selected by the user. The control panel also provides a digital display of actual motor speed and allows the user to digitally specify a maximum motor speed. The output of the foot switch is adjusted by a transfer function and then used to control motor speed, and the transfer function is adjusted as necessary to precisely conform the actual motor speed and thus the displayed speed to the selected maximum speed. The feedback path for the actual motor speed is entirely digital, so that a highly accurate value of actual speed is available for display and for adjustment of the transfer function.