Patent · US Expired

Circuit for controlling a dryer-program switching device

US4215486A · kind A · utility

14Cited by
3References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 14, 1978
Grant dateAug 5, 1980
Priority date
Expiry dateNov 14, 1998

Classification

  • Technology area (CPC D)Textiles; Paper
  • CPC primaryD06F2105/50
  • WIPO fieldOther consumer goods
  • WIPO sectorOther fields

Abstract

Circuit for controlling the program timer of a laundry dryer as a function of the moisture-dependent resistance of the laundry. A storage capacitor charged from a d-c voltage source together with laundry resistance resulting from wet laundry bridging two electrodes and resistance determine the duty cycle or frequency for an oscillator. The output of the oscillator is fed to a filter and from there as one input to a comparator. A reference value setter is fed to another input of the comparator. The output of the comparator is functionally connected to the program timer. This circuit arrangement makes possible measurement of low residual moisture values in the laundry and thereby permits the start of the post-drying phase without heating on reaching this low residual moisture value.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.