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:
Jul. 25, 2000
Filed:
Dec. 31, 1998
Hideyuki Morikawa, Tokyo, JP;
UniFlows Co., Ltd., Tokyo, JP;
Abstract
A high accuracy and high precision pump for fluids, specifically for use in chemical and/or medical analyzers includes a female-thread or nut inside the motor rotor shaft and a male-thread or lead screw mated with the female-thread or nut supported by a bearing that restricts the rotation of the lead screw. The lead screw slides axially, and is connected directly to a plunger or piston which is moved forward or backward by the rotation of the motor rotor. The end of the plunger or piston cylinder chamber includes a common fluid path switch-over valve by which fluid flow may be switched over to a plurality of fluid paths. Movement of pumping components, including pump(s), nozzle(s), valve(s), and tubing, is unified to eliminate volume changes due to changes in fluid tubing flexion.