Method of making a refrigerator cabinet liner having non-crinkled corners
US4917841A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 7, 1988 |
| Grant date | Apr 17, 1990 |
| Priority date | — |
| Expiry date | Oct 7, 2008 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29L2031/7622
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A refrigerator liner of a vacuum formed plastic with a thickness of about 0.007" to 0.050" has each corner formed without crinkling when thermal insulation material is foamed against the outer surface of the liner. The non-crinkling of each corner of the refrigerator liner is accomplished through forming each of the corners with a flat surface having its periphery as a circle during vacuum forming of the refrigerator liner rather than with a spherical radius. This enables the flat surface to be placed in tension when moved against a corresponding flat surface of a foam plug by the pressure produced during foaming of the foamed thermal insulation material. This results in each corner having a central portion with a convex cross section and an outer portion surrounding the central portion and concave in cross section whereby it does not appear to be crinkled.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.