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, 1989
Filed:
Oct. 22, 1987
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F04B / ; F04B / ; F04B / ;
U.S. Cl.
CPC ...
417-2 ; 417265 ; 210101 ;
Abstract
A low pulsation pump device has a pulse motor, two plungers adapted to be driven by the pulse motor, a pressure sensor disposed on the output side of the plungers, a storage for storing values of pressures detected by the pressure sensor during each of a number of periods, a high speed region during which the rotational speed of the pulse motor is increased. The pulse control has an optimization function which determines, on the basis of pressure information which was obtained during the last period, the location of a high speed region in each period in such a manner as to reduce pulsations.