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:
Sep. 02, 2003
Filed:
Aug. 29, 2001
Ari Väisänen, Hyvinkää, FI;
KCI Konecranes Plc., Hyvinkää, FI;
Abstract
A method and an apparatus for controlling release of a hoisting motor brake in a hoisting apparatus, where electricity is used as the driving force and a squirrel cage motor as the hoisting motor for hoisting or lowering a load attached to a hoisting member of the hoisting apparatus. Controlling of brake release comprises measuring the current and supply voltage of the hoisting motor after the start-up period of the hoisting motor and determining a variable which describes the load of the hoisting apparatus from the current and supply voltage. The variable describing the load is compared with a pre-determined limit value and hoisting or lowering of the load is interrupted if the variable describing the hoisting apparatus load exceeds the limit value set for the hoisting movement when the load is hoisted or if it exceeds the limit value set for the lowering movement when the load is lowered.