Device for sensing food weight of microwave oven
US5422464A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 8, 1993 |
| Grant date | Jun 6, 1995 |
| Priority date | — |
| Expiry date | Sep 8, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B6/6411
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A food weight sensing device of a microwave oven using a variable capacitor of which the capacitance is varied in accordance with pressure applied thereto. The device comprises of first and second electrodes placed on a side portion of a lower surface of a cooking chamber, the side portion being included in a rotating trail of a roller applied with part of the food weight, each of the electrodes comprising a metal plate spring. A spacer is interposed between the first and second electrodes to space out the electrodes from each other at a predetermined interval. A rubber plate engages with the first electrode for transmitting the food weight to the first electrode. The first electrode comprises a center circular push part, an outer flange part and at least two arcuate ribs connecting the center circular push part to the outer flange part. The spacer is made of a metal so as to electrically connect the first electrode to a printed circuit board. This device precisely and easily senses the food weight by sensing a varied capacitance of the variable capacitor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.