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:
Mar. 30, 2004
Filed:
Apr. 05, 2002
Arthur Eugster, Romanshorn, CH;
Eugster Frismag AG, Romanshorn, CH;
Abstract
An espresso machine is provided with an infusion piston displaceable inside an infusion cylinder. The infusion piston is force-connected to a spring and to a device for activating the infusion piston and, in a first position, tightly encloses ground coffee inside an infusion chamber of the infusion cylinder between itself and an outlet sieve. A pressurized water inlet is connected to the infusion chamber, the infusion piston is automatically pushed by the pressure of the infusion water flowing into the infusion cylinder and counter to a spring force to a second predetermined position, thereby expanding the infusion chamber, whereupon during a pressure drop inside the infusion chamber the infusion piston is returned automatically to the first position. The infusion piston can essentially be displaced proportional to a pressure increase inside the infusion chamber, caused by the infusion water flowing in, until it reaches a nominal opening pressure for a frothing valve that closes off the infusion chamber in a downstream direction.