Patent ID: 8387516

Claim:
A coffee maker comprising: (a) a heated reservoir for holding a volume of hot water such that the hot water forms a level within the heated reservoir with an air space above the hot water; (b) an inlet to the heated reservoir for adding water; (c) a level controller for maintaining a constant hot water level in the heated reservoir; (d) a first vent line communicating between the air space in the heated reservoir and the atmosphere; (e) a vent valve in the first vent line, the vent valve having a position that is normally open and being movable to a closed position when exposed to pressurized air; (f) a siphon tube for discharging hot water from the heated reservoir, the siphon tube having an intake at or below the level of hot water, then rising to a top above the level of hot water, and then descending to an outlet at, a level that is always below the level of hot water, the siphon tube being free of any pump means; (g) a second vent line communicating between the top of the siphon tube and the atmosphere; (h) a stop valve in the second vent line, the stop valve having a position that is normally closed and being movable to an open position; (i) a container for coffee grounds located below the siphon tube outlet; (j) an air pump having a discharge line that communicates with the heated reservoir and the vent valve; and (k) a controller for initiating a brewing cycle by turning the air pump on and thereby closing the vent valve and beginning siphon flow through the siphon tube, for continuing the brewing cycle by turning the air pump off after a period of less than about five seconds such that the vent valve returns to the open position and siphon flow through the siphon tube continues, and for terminating a brewing cycle by momentarily opening the stop valve.