Patent · US Expired

Microwave oven

US4284868A · kind A · utility

13Cited by
10References
39Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 21, 1978
Grant dateAug 18, 1981
Priority date
Expiry dateDec 21, 1998

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05B6/72
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A microwave oven having a directional rotating antenna axially supported on an axis of one wall of a microwave oven cavity of the microwave oven which provides circularly symmetric uniform energy distribution of microwave energy within the microwave oven cavity and consistent heating of a product in the microwave oven cavity. The directional rotating antenna includes a two-by-two array of antenna elements where each element is an end driven half-wavelength resonating antenna element supported by a length of conductor perpendicular to the wall of the microwave oven cavity. A parallel plate transmission line connects to each of the supports, four of which join at a junction which connects to a cylindrical probe antenna. The probe antenna is excited by microwave frequency currents of a waveguide adjacent to the wall of the microwave oven cavity. The directional antenna is rotated by a moving stream of air circulated through the microwave oven cavity. A dome having a flattened conical shape extending outwardly in the wall of the microwave oven cavity provides a nearly circular recess partially surrounding the directional rotating antenna and provides uniform energy distribution in the …

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