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:
Sep. 27, 1977
Filed:
May. 29, 1975
Paul Bryce Welsh, Wilmington, DE (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
A method for cooling gas chromatograph ovens with ambient room temperature air utilizing two separate air passages through an oven door. The door remains closed during the heating and cooling cycles which take place inside the oven housing. A rotating stirring fan internal to the oven creates regions of relatively higher and lower air pressures. The two air passages are disposed adjacent to these pressure regions to draw room temperature air into the oven, and to exhaust hot air from the oven. Within the oven door there is a movable, spring mounted, oven closure hatch in which the first air passage is located. This air passage is opened and closed by a movable cover. The hatch also establishes the second air passage when it is spaced-apart from the oven housing. Both air passages are opened and closed in response to movement of the hatch. An actuation device that can interface with a programmable actuation controller opens and closes the hatch as necessary for cooling the inside of the oven housing.