# US 7,743,695 B2 · Espresso coffee maker having an espresso brew unit > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,743,695 B2 - Document ID: US7743695B2 - Status: Granted - Kind: B2 - Application number: 11/487,238 - Filed: 2006-07-14 - Published: 2007-01-18 - Granted: 2010-06-29 - Earliest claimed: 2005-07-16 - Assignees: Eugster/Frismag AG - Inventors: Max Oehninger - Web page: https://patentgrep.com/patent/US7743695B2 ## CPC - A47J 31/3609: {Loose coffee being employed} - A47J 31/3614: {Means to perform transfer from a loading position to an infusing position} - A47J 31/4496: {Means to produce beverage with a layer on top, e.g. of cream, foam or froth} - A47J 31/461: {Valves, e.g. drain valves} - A47J: KITCHEN EQUIPMENT; COFFEE MILLS; SPICE MILLS; APPARATUS FOR MAKING BEVERAGES ## Abstract In an espresso coffee maker having an espresso brew unit (1) and a coffee outflow duct (18) in fluid-conductive connection with the espresso brew unit via a crema valve (15) and having an end sided coffee outflow (19), no brewed residual coffee should remain in the coffee outflow duct nor leak out, for instance as leakage, through the coffee outflow. In order to avoid this, a return-flow suction unit (21), which is preferably independent except for a drive means, is in fluid-conductive connection with the coffee outflow duct (18) between crema valve (15) and coffee outflow (19), which is automatically activated when a brewing process is finished. ## Claims ### Claim 1 An espresso coffee maker having an espresso brew unit (1, 1a, 1b) and a coffee outflow duct (18) in fluid-conductive connection with the espresso brew unit via a crema valve (15) and having a coffee outflow (19) characterized in that a return-flow suction unit (21, 21a, 21b) is in fluid-conductive connection with said coffee outflow duct (18) between said crema valve (15) and said coffee outflow (19), and said return-flow suction unit (21, 21a, 21b) is automatically activated to suck residual coffee out of the coffee outflow duct (18) when a brewing process is finished. ### Claim 2 (depends on 1) The espresso coffee maker according to claim 1, wherein said movable brew chamber element constitutes a brew chamber cylinder (3) disposed substantially underneath a top ram (5) so that, together with it, it can form a brew chamber (2), in order to completely close said brew chamber (2), said brew chamber cylinder (3) can be moved substantially in vertical direction onto said top ram and, by substantially vertical lowering can be disconnected from said top ram (5), in order to completely open said brew chamber (2) in case of disconnected brew chamber cylinder (3), and vice versa, for closing said brew chamber, said top ram (5) can be moved substantially in horizontal direction, and coupling elements (25, 26, 27) are disposed between said brew chamber cylinder (3) and a piston rod (24) on said suction piston (23) of said return-flow suction unit (21) so that, by horizontally moving said top ram (5) into a completely open position of the brew chamber, they can be decoupled and by reverse horizontal movement of top ram (5) into a closure position of said brew chamber (2) can be coupled and are suited, in a coupled state, to transfer the vertical movement of said brew chamber cylinder (3) onto said suction piston (23). ### Claim 3 (depends on 2) The espresso coffee maker according to claim 2, wherein at least one (26, 27) of said coupling elements is coupled to said brew chamber cylinder (3) and at least another one (25) of said coupling elements is in connection with said piston rod (24) of said suction piston (23). ### Claim 4 (depends on 1, 2, 3) The espresso coffee maker according to any one of claims 1, 2 and 3, wherein said suction cylinder (22) receiving said suction piston (23) forms one unit with said top ram (5) and said coupling elements (25, 26, 27) comprise, between said brew chamber cylinder (3) and said piston rod (24), on one hand, a slit (26) open on the front in a drive rod (27) at said brew chamber cylinder (3) and, on the other hand, a pin (25) on a piston rod (24) of said suction piston (23), which may be inserted into said slit (26) by horizontally moving said top ram (5). ### Claim 5 (depends on 1, 2) The espresso coffee maker according to any one of claims 1, 2 and through 3, wherein a suction duct (28) is branched off from coffee outflow duct (18) between said crema valve (15) and said coffee outflow (19) and opens into a suction cylinder head, and that said drain duct (29) extends on the outside downwardly from an opening in said suction cylinder (22) at a location above said piston (23) in its lower dead-center position. ### Claim 6 (depends on 4) The espresso coffee maker according to claim 4, wherein a suction duct (28) is branched off from coffee outflow duct (18) between said crema valve (15) and said coffee outflow (19) and opens into a suction cylinder head, and said drain duct (29) extends on the outside downwardly from an opening in said suction cylinder (22) at a location above said piston (23) in its lower dead-center position. ### Claim 7 An espresso coffee maker having an espresso brew unit (1, 1a, 1b) and a coffee outflow duct (18) in fluid-conductive connection with the espresso brew unit via a crema valve (15) and having a coffee outflow (19) wherein a return-flow suction unit (21, 21a, 21b) is independently provided and is in fluid-conductive connection with said coffee outflow duct 18 between said crema valve (15) and said coffee outflow (19) and said return flow suction unit (21, 21a, 21b) is automatically activated to suck residual coffee out of said outflow duct (18) when a brewing process is finished.