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. 07, 1995
Filed:
Feb. 19, 1993
Howard North, Jr, Los Gatos, CA (US);
Kenneth F Uffenheimer, Los Gatos, CA (US);
Becton Dickinson and Company, Franklin Lakes, NJ (US);
Abstract
The present invention relates to a system for controlling the movement or transport of objects such as cells and other particles in a moving liquid stream. More particularly the invention relates to a system including a vacuum pump which pulls the sheath fluid from an open supply reservoir through a flow cell assembly where cell analysis occurs and discharges the flow cell effluent to an open waste reservoir. A pressure drop is created through the conduit leading from the supply reservoir to the flow cell which aspirates the cell suspension from an open sample vessel into and through the flow cell. The vacuum is regulated by controlling the electric power applied to the vacuum pump motor. Starting, stopping, reverse flushing, and draining of the flow cell assembly are controlled by programming the operation of four electric solenoid valves in fluid communication with the flow cell inlet and outlet passages, the operation of a reverse flush pump and, the operation of an electrically controlled tube lifter. A deaerator is provided to remove some of the air dissolved in the sheath fluid provided to the flow cell assembly to prevent the release of air and formation of adherent air bubbles in sensitive areas of the flow cell assembly.