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. 22, 1994
Filed:
May. 07, 1992
Kuah T Hock, Champaign, IL (US);
Forma Scientific, Inc., Marietta, OH (US);
Abstract
A biological safety cabinet comprising an enclosure having two side walls, a rear wall, a bottom wall defining a work surface, a top wall and a front window, below which access can be had to the work surface, the enclosure defining a work area. A plenum surrounds the enclosure and communicates with the work area. A blower induces a negative pressure within the plenum to circulate contaminated air through a filter within the enclosure, which creates a downwardly directed air curtain of work area air below the window. A vertically oriented outwardly facing channel section is secured to each side wall adjacent the window. Each channel section has a downwardly and forwardly sloping upper end, a rear edge of which extends above a lower edge of the window and a front edge of which extends below the lower edge of the window. The plenum communicates with each channel. Ambient air and air within the air curtain adjacent upper lateral edges of the air curtain are accelerated downwardly by the channels to reduce the tendency of the ambient air and the cabinet side walls to decrease the velocity of the air curtain, thereby strengthening the air curtain and reducing a tendency of the ambient air and the work area air to interchange.