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:
Jun. 04, 2002
Filed:
May. 23, 2001
Luigi Bassi, Lodi, IT;
Stefano Oggioni, Milan, IT;
International Business Machines Corporation, Armonk, NY (US);
Abstract
A volumetric pump for dispensing a controlled and continuous flow of viscous fluid. The pump according to a preferred embodiment of the present invention can ideally dispense from a minimum of 1 mg/sec to 1 g/sec for fluids with a viscosity from 2,000,000 cps (Centipoise) down to 10,000 cps. Such flexibility in the range of viscosity extends the application fields of this pump to microelectronics as well as automotive and consumer products manufacturing. Two cams mounted with an opposing position of 180° on the same shaft generate an alternate motion of two concentric pistons. The alternate movement of the external piston in one phase pumps out the material through a dispensing needle and allows in the returning phase the viscous fluid to be charged in the dispensing chamber from the feeding container. The alternate movement opens and closes the vents during the different working phases.