The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 31, 1987
Filed:
Aug. 07, 1985
Nippon Sanso Kabushiki Kaisha, Tokyo, JP;
Abstract
Disclosed is a vacuum-heat-insulated cooking utensil and a method of manufacturing the same. Inner and outer containers are prepared each having a tubular side wall and an end wall closing the end of the side wall. The inner container is positioned in the outer container with the respective bottoms being in contact with each other through a first brazing material, with the other ends of the side walls fitted to each other with a gap which constitutes a vacuum sealing section, and with an annular space being defined between the side walls. A second brazing material having a melting point higher than that of the first brazing material is positioned at the vacuum sealing section. An assembly of the containers and the brazing materials is placed in a vacuum furnace. The furnace is evacuated to evacuate the annular space. Temperature within the furnace is raised above the melting point of the second brazing material to melt the first and second brazing materials. The temperature within the furnace is then lowered to a level lower than a solidifying point of the second brazing material but higher than the melting point of the first brazing material to solidify the second brazing material to seal the vacuum sealing section. Subsequently, pressure within the furnace is raised to a level approximate to the atmospheric pressure. The temperature within the furnace is lowered to solidify the first brazing material to bring the end walls of the respective containers into intimate contact with each other to form a heat receiving bottom of the cooking utensil.