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:
Dec. 07, 1993
Filed:
Dec. 19, 1991
Alton B Eckert, Jr, New Fairfield, CT (US);
Dennis M Gallagher, Danbury, CT (US);
Thomas M Pfeifer, Bridgeport, CT (US);
Richard P Schoonmaker, Wilton, CT (US);
Pitney Bowes Inc., Stamford, CT (US);
Abstract
A mailing machine base adapted to have a postage meter mounted thereon, wherein the meter has a postage printing drum having a home position, and the base comprising, structure for moving the drum, a d.c. motor for driving the drum moving structure, a microprocessor, a power switch connected between the d.c. motor and microprocessor for driving the d.c. motor, a power switch connected between the d.c. motor and microprocessor for dynamically braking the d.c. motor, a comparator connected between the microprocessor and d.c. motor for receiving therefrom a signal corresponding to the back e.m.f. voltage thereof and providing a comparison signal to the microprocessor, and the microprocessor programmed for, energizing the braking switch for a first time interval predetermined to cause the d.c. motor to decelerate the drum at a substantially constant rate from a substantially constant velocity thereof, energizing and deenergizing the braking switch with a second signal successively during each of a predetermined number of successive second predetermined time intervals, providing a reference voltage for the comparator having a value which is less than the back e.m.f. voltage corresponding to the constant velocity, energizing the driving switch with a third signal for a third predetermined time interval, determining whether the drum is in the home position, determining whether the back e.m.f. is greater than the reference voltage if the drum is not in the home position, energizing the braking switch with a fourth signal for a fourth predetermined time interval if the drum is in the home position to ensure the drum is stopped in the home position, energizing the driving switch for the third time interval if the back e.m.f. voltage is not greater than the reference voltage and delaying the third time interval of energization of the driving switch if the back e.m.f. is greater than the reference voltage to permit the drum to coast.