Vertable tray and lid assembly for heating foods
US4399159A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 13, 1981 |
| Grant date | Aug 16, 1983 |
| Priority date | — |
| Expiry date | Jul 13, 2001 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB65D81/343
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A tray and lid assembly formed of synthetic plastic material for containing a pre-cooked meal which is to be stored in the frozen state and thereafter reheated before being served. The tray which has a polygonal shape is provided with an outwardly-extending continuous flange running along the upper edge of the sides to surround the open mouth. The lid, which has the same geometry as the tray and is of the same material, has a downwardly-extending peripheral skirt which engages the periphery of the tray flange and a continuous underside strip which is received within the mouth of the tray. Because of the presence of the meal in the tray, when the assembly is subjected to freezing temperatures, the lid contracts to a somewhat greater extent than the tray, as a consequence of which the skirt is caused to press against the flange to effect an outer seal, whereas the strip is inwardly displaced from the mouth to provide a leakage path. When, however, the assembly is thereafter subjected to heating, the lid proceeds to expand to a somewhat greater extent than the tray; but before the strip is caused to press against the mouth of the tray to effect an inner seal, the expanding heated air …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.