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:
Apr. 13, 2004
Filed:
Sep. 21, 2001
Joseph M. Plasz, Grafton, WI (US);
Mark E. Ubl, Oak Creek, WI (US);
MHE Technologies, Inc., Wilmington, DE (US);
Abstract
A material handling system for lifting a load and a method sensing an unstable state of the material handling system. The system includes a motor, a brake and a drive. The method includes storing a model of the motor in the drive and generating a signal in the drive. The signal has a voltage and a frequency. The method further includes providing the signal to the motor, sensing a current value of the signal, determining a modeled value based in part on the sensed current value, comparing an actual value to the modeled value to determine whether the load is stable, and generating an output that sets the brake when the load is potentially unstable.