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:
Nov. 27, 1984
Filed:
Mar. 29, 1982
Applicant:
Inventor:
Borge R Jensen, Brussels, BE;
Assignee:
Grundfos A/S, Bjerringbro, DK;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F04B / ; F04B / ;
U.S. Cl.
CPC ...
417 36 ; 417 44 ;
Abstract
An apparatus for controlling the operation of a pump, especially a submersible pump, and particularly for controlling a water level in connection with cellar drainage pumps, comprises at least one level detector using the principle of acoustic impedance for detecting the presence or absence of liquid to be pumped, said level detector being electrically connected to a control circuit controlling a switching device for the pump.