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:
Feb. 20, 1979
Filed:
Aug. 04, 1977
Tom L Erb, Austin, TX (US);
Ramsey Engineering Company, St. Paul, MN (US);
Abstract
In a switching circuit for controlling the level of material in a container, a first counter accumulates pulses generated at a rate inversely related to the level of the material up to a first predetermined total. A second counter accumulates clock pulses up to a second predetermined total representing a fixed counting interval. The counters are connected in a race circuit wherein the one to reach its predetermined total first resets both counters and controls the race circuitry. The first counter sets a control circuit to indicate a low level condition or to activate an alarm, and the second counter resets the control circuit to indicate a high level condition. After the control circuit has been set by the first counter, the race circuit is responsive to a third predetermined total of the first counter, less than the first predetermined total, representing, for example, a level to which a container is to be filled. The first and third predetermined totals provide a hysteresis effect to prevent the switching circuit from 'hunting' around the level at which material is to be added or an alarm condition shown.