Method of determining the imbalance of a laundry drum

US6973392B2 · kind B2 · utility

Assignee

• Diehl AKO Stiftung & Co. KG · DE

Inventors

• Stefan Zeh · Schallstadt, DE
• Martin Weinmann · Bad Waldsee, DE

Key dates

• Filing date: Jan 21, 2005
• Grant date: Dec 6, 2005
• Expiry date: Jan 21, 2025

Classification

• Technology area (CPC D): Textiles; Paper
• CPC primary: D06F34/16
• WIPO field: Other consumer goods
• WIPO sector: Other fields

Abstract

Before a washing machine is switched over to a very high spin speed in the spin program of the washing machine, the existing imbalance due to irregular distribution of laundry in the drum should be checked. If the imbalance is too strong, the spin program should be interrupted if there is a threat of excessively high bearing forces to be expected. The fluctuation in rotary speed, which may have a high frequency due to the drum speed, and of the power consumption of the washing machine motor measured downstream of the direct current intermediate circuit prior to the feed thereof into the inverter for producing the rotary field in the motor. There, the vector product of the current and the voltage for imbalance measurement by determining power is blocked off from mains network interference effects by the high capacitance of the direct current intermediate circuit.