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. 05, 2000
Filed:
Jun. 26, 1998
Applicant:
Inventor:
Frank Hofmann, Hamburg, DE;
Assignee:
Walter Hofmann GmbH, Rellingen, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F04B / ;
U.S. Cl.
CPC ...
417539 ; 417 53 ;
Abstract
A method and apparatus for supplying liquids by means of a pump combination comprising two single oscillating displacement pumps is provided, wherein a supply pressure of the pump supplying liquid into a user duct is used as a control value of a pressure controller, such that a pressure stroke movement of the other pump which is generating a pre-compression pressure, is discontinued when the pre-compression pressure equals the supply pressure, and the pre-compression pressure is maintained.