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:
May. 08, 1990
Filed:
Sep. 07, 1988
Richard P Price, Parma Heights, OH (US);
Nordson Corporation, Westlake, OH (US);
Abstract
Apparatus and method for dispensing fluid material whereby the fluid is discharged from a nozzle onto a workpiece. Delivery of fluid to the nozzle is controlled by a metering valve located in close proximity to the nozzle. The flow of dispensed fluid is sensed by a pressure transducer disposed to sense the pressure drop across the nozzle. The pressure transducer generates a feedback signal which can be applied by way of a closed loop control system to an electropneumatic servovalve which operates a double-acting air cylinder the pressure drop across the nozzle thereby controlling the flow of dispensed fluid in accordance with a driving signal. Where the dispenser is carried by a robot, the driving signal can be correlated to the relative speed between the workpiece and the nozzle to accurately control the amount of fluid per unit length contained in a bead deposited on the surface of the workpiece. Due to the rapid response of the system such precise control is possible even during relatively rapid changes in the relative speed between the nozzle and the workpiece. Also disclosed are means for insuring that the volume of fluid dispensed over a predetermined interval corresponds to a desired setpoint thereby correcting for changes in the intrinsic viscosity of the dispensed fluid as may be caused by changes in its temperature.