Washing machine monitor - measures pressure difference over non-critical path to indicate build-up of dirt and lint

摘要

The system to monitor the build-up of dirt and lint in a clothes washing machine, together with display of the lint filter state and/or heat exchanger, measures pressure difference over a path contg. components which are not damaged by soiling. Pref. the measurement lines are connected in front of and at the outlet of the washing drum (4), linked to the heating register (6) switched in series in front of the drum (4) and at the outlet. A signal lamp or LED indicates a pressure drop as a result of build-up and/or the appts. is switched off. The difference pressure is monitored throughout the whole drying program, or part of the program. The difference pressure is not taken during reversing pauses and at the time the drum (4) reverses its rotation. The signal lamp or LED is illuminated if the difference pressure drops below the threshold value after a time span within the first program section, and an optical and/or acoustic signal is generated at the end of the drying program on opening the machine door. The illumination of the warming lamp or LED can also switch off the drying program. The signal is stored, and passed to the indicator on the start of a new program. The lamp or LED is lit to give a flickering light. ADVANTAGE - The measurement of the pressure difference, as an indication of build-up is independent of outside influences.