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:
Oct. 08, 1991
Filed:
Nov. 20, 1989
William M Rucki, Aurora, OH (US);
Jeanne M Leidy, Rocky River, OH (US);
Nordson Corporation, Westlake, OH (US);
Abstract
A foam material dispensing system is provided with a control which measures the amount of high viscosity liquid material delivered to a mixer, determines the amount of pressurized gas required to be injected into the mixer in order to produce a foamable material with a desired gas concentration, measures the amount of gas actually delivered to the mixer, and generates a cumulative error signal representing the difference between the required amount of gas and the gas actually delivered. A control signal is generated to regulate the flow of gas to the mixer in relation to the magnitude of the error signal. A digital flow meter generates a pulse for each incremental amount of liquid material delivered to the mixer during an interval of time. During each successive interval, the pulses are counted and the count is multiplied by a preset gas-to-material ratio, from which the measured gas flow is subtracted and the difference added to the cumulative error term. The error term is combined with a term proportional to the amount of liquid material delivered over a predetermined number of successive time intervals to produce the control signal.