Method and system for operating a clothes washing machine
View Patent ↗A clothes washing machine system and control methods. The washing machine system includes a cabinet having a drum rotatably mounted therein. A motor is coupled to the drum for rotating the drum within the cabinet. A memory device is accessible by a processor, such as a digital signal processor (DSP). The memory contains program code for implementing a method that includes determining the end of the washing machine's spin cycle by monitoring a parameter of the washing machine.
1. A method of controlling a spinning washing machine drum, the method comprising:
spinning the drum;
monitoring a predetermined parameter of the spinning drum; and
stopping the drum in response to the monitored parameter,
wherein the predetermined parameter is inertia, and
wherein the monitoring thereof includes determining the combined inertia of the drum and the contents of the drum by fluctuating variables of the drum about predetermined values.
2. The method of claim 1 , wherein monitoring the predetermined parameter includes:
determining a first value for the predetermined parameter;
determining a second value of the predetermined parameter; and
determining the change in the parameter between the first and second values.
3. The method of claim 1 , wherein monitoring the predetermined parameter includes continuously monitoring the parameter until the desired change.
4. The method of claim 1 , wherein monitoring the predetermined parameter includes using a parameter estimator.
5. The method of claim 4 , wherein parameter estimator is a recursive least squares estimator.
6. The method of claim 5 , wherein the parameter estimator is adaptive to parameter changes.
7. The method of claim 1 , wherein determining the combined inertia includes spinning the drum at a substantially constant mean speed.
8. The method of claim 1 , wherein determining the combined inertia includes fluctuating the drum speed about a predetermined speed value.
9. The method of claim 8 , wherein fluctuating the drum speed includes applying a speed demand signal to a speed controller, and applying a dither signal to the speed demand signal.
10. The method of claim 1 , wherein monitoring the predetermined parameter includes monitoring the rate of change of the predetermined parameter.
11. The method of claim 10 , wherein stopping the drum in response to the monitored predetermined parameter includes stopping the drum in response to the rate of change reaching a predetermined value.
12. The method of claim 11 , wherein stopping the drum in response to the monitored predetermined parameter includes stopping the drum in response to the rate of change staying within a predetermined range for a predetermined time period.
13. The method of claim 1 , further comprising detecting a drum unbalance in response to the predetermined parameter.
14. The method of claim 13 , further comprising quantifying the drum imbalance in response to the predetermined parameter.
15. The method of claim 14 , flirt her comprising selecting the drum spin speed in response to the detected drum imbalance.
16. The method of claim 13 , wherein the drum spins about an axis, and wherein detecting the drum unbalance includes monitoring movement of the drum axis.
17. The method of claim 16 , wherein the predetermined parameter is inertia.
18. A program storage device storing program code implementing a method of determining a load unbalance mass contained in a spinning washing machine drum driven by a motor, the method comprising:
spinning the drum;
monitoring at least one predetermined parameter of the spinning drum; and
stopping the drum in response to the at least one monitored parameter;
wherein the at least one predetermined parameter includes the inertia of the spinning drum, and
wherein the monitoring thereof includes determining the combined inertia of the drum and the contents of the drum by fluctuating variables of the drum about predetermined values.