Patent ID: 7252033

Claim:
An automatic coffee maker comprising a valve mechanism, a grinding mechanism, a powder fineness adjusting mechanism, a cover having a front groove, and a bean container, wherein: the valve mechanism includes an electromagnetic valve combined with a micro switch to drive one end of the electromagnetic valve connected to an extension member, another end of said extension member being connected to a covering board having an opening, and a spring being provided between the covering board and the electromagnetic valve; the grinding mechanism includes a motor including an extended rotating shaft, an elongated block, a bearing, a spring plate, a spring, a U-shaped bulkhead, a cylinder, two outer grinding members, an inner grinding member, a front plate having threads on a center, upper and lower shells, a projected upper hopper member and a projected bottom powder outlet, with said cylinder having an inward extending rim, with each of said two outer grinding members having a plurality of inclined teeth on one surface, with said inner grinding member including a hollow feed rod formed with a lead screw thereon; and the powder fineness adjusting mechanism includes a half-circular adjustment member, a join board having a front and a back, a staged abutment member, and an bearing, with said half-circular adjustment member including an upwardly projected lever and a recess provided under the upwardly projected lever, with said join board including a projection on the front and a bar on the back, with said staged abutment member having one side and another side and including circumferential teeth at the one side, outer threads at the another side and an axis projected inwardly from a center of the outer threads for being received by the bearing of the powder fineness adjustment mechanism, with the bar resting between a pair of adjacent circumferential teeth of said staged abutment member; whereby in a powder fineness adjustment for producing coarse coffee powder, pivoting the lever toward one end of the front groove will pivot the join board and the staged abutment member and move the staged abutment member outward to push the two outer grinding members and the inner grinding member outwardly so as to increase a space therebetween; and in a powder fineness adjustment for producing fine coffee powder, pivoting the lever toward another end of the front groove will pivot the join board and the staged abutment member and move the staged abutment member inwardly to push the two outer grinding members and the inner grinding member inwardly so as to decrease the space therebetween.