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. 29, 1994
Filed:
Feb. 01, 1993
Stephen R Orth, Chicago, IL (US);
Burton L Siegal, Skokie, IL (US);
Johnson Pumps of America, Inc., Schiller Park, IL (US);
Abstract
An automatic control for a liquid pump which assures that the pump starts pumping when the liquid reaches a predetermined level and the pump is stopped when the level has fallen to a second predetermined level. The control includes a permanent magnet mounted in a float that is contained within a float chamber and which has a bottom opening through which the liquid can enter the float chamber. A top portion of the float chamber is provided with a one-way valve so as to allow air to escape from the float chamber, but which prevents air from entering the float chamber such that when the float moves up with the liquid, the magnet actuates a magnetic responsive switch such as a reed switch to cause the motor to start to drive the pump. As the pump lowers the level of the liquid, the level of the liquid in the float chamber does not fall because of the partial vacuum within the top of the float chamber and, thus, the magnet continues to energize the pump. When the liquid level falls to the bottom of the float chamber, air rushes into the chamber and allows the retained liquid within the float chamber to fall out the bottom and the magnet bearing float falls to the bottom which turns off the pump motor.