Microwave reflective energy concentrating spacer

Claim 1

A foldable and collapsible microwave reflective energy concentrating spacer that can be shipped in a food package for facilitating the heating of food in a microwave oven having a microwave transparent supporting shelf located an indeterminate distance above a microwave reflective oven floor comprising, a spacer body defining an upper support surface for supporting a food article thereon and a lower microwave reflective surface spaced below the supporting surface by a distance of about 1/4 wave length of the microwave energy supplied by the oven, whereby when said microwave energy has a wavelength of 12 cm said distance is about 2.5 to 3 cm, said microwave reflective surface comprising microwave reflective sheet material extending the width and breadth of the spacer body and being substantially aligned with the support surface, a portion of the spacer body between the support surface and the reflective surface being composed of microwave transparent material, whereby microwave energy from the oven striking the reflective surface of the spacer body from above is reflected upwardly therefrom such that the reflective surface acts as an artificial oven floor forming a region of concentrated phase-reinforced microwave energy inside the food or at the surface of the food article resting upon said upper support surface to thereby enhance heating of the food by providing a uniformly high level of heating without regard to the distance between the supporting shelf of the oven and the oven floor, and said spacer body is formed from a plurality of panels of microwave transparent sheet material connected by hinges at intersecting edges which are parallel to one another to define a spacer that is adapted to be folded flat for compact storage and shipment in said package by folding the spacer body at the parallel hinges to a flattened condition, one of the panels comprising a horizontal bottom wall panel including a metal foil defining said microwave reflective surface and movable members operationally associated with the panels to hold the spacer body in an upright condition during use to support the weight of the food resting on the upper support surface.