Automatic fluid temperature controller and washing machine incorporating same
US6305610A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 9, 2000 |
| Grant date | Oct 23, 2001 |
| Priority date | — |
| Expiry date | Jun 9, 2020 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD06F2105/04
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
A water temperature control circuit for a washing machine includes window detector and dual water valve drivers to modulate the hot and cold water valves to maintain the water temperature at a desired level. A temperature selector switch provides hot, regulated hot, warm, regulated warm, and cold temperature settings for the washing machine. During regulated temperature operation the window detector modulates one of the water valves to maintain the water temperature within a narrow temperature band. The window comparator includes two comparators that receive a common temperature input from a temperature sensing element. As such, no shunt resistor is required for one or the other comparators, thus improving accuracy. The control circuit operates open loop with respect to the hot and cold water valves that it controls, utilizing instead only the temperature input for controlling the proper water valve when enabled.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.