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. 04, 1989
Filed:
Oct. 13, 1988
Robert J Fox, Bowling Green, OH (US);
Other;
Abstract
A fluid-operated, time delay control and system embodying same are set forth. The time delay control includes an accumulator chamber communicating with a source of fluid under negative pressure or vacuum and a second chamber having a partition dividing it into two parts, a first of which communicates with the accumulator chamber. The second part communicates with a vacuum-sensitive switch which is energized when sensing a vacuum of a predetermined value. The partition has a check valve for maintaining the vacuum switch in communication with a vacuum after the vacuum is released at the source and the pressure rises in the first part of the second chamber. An adjustable flow control valve in the partition slowly releases the vacuum which the switch senses. The switch then reverts to a de-energized condition when a predetermined value is reached. A filtering system incorporates the time delay control with the control controlling a vacuum break valve and a motor for moving a strip of filter media.