Ground coffee extraction apparatus

A ground coffee extraction apparatus, comprising a base coupled with an outer annular body from above, wherein the outer annular body is installed sequentially therein with a downward pressing element, a sliding element, and an upper cover, the downward pressing element being peripherally provided with an O-ring, the sliding element being formed with a plurality of water receiving sections and a plurality of retaining portions, the upper cover being formed with a plurality of water inlet sections and a plurality of engaging portions corresponding in position to the water receiving sections and the retaining portions of the sliding element, respectively, a resilient element being provided below and adjacent to each said retaining portion of the sliding element, a delivery system being coupled to a side of the extraction apparatus;

• wherein a fixed amount of ground coffee is loaded into a filter cup, and a pump in the delivery system draws cool water from a cool water tank into the water inlet sections of the upper cover of the extraction apparatus so that the cool water exerts a downward force greater than a resilient force of the resilient elements, thus enabling the O-ring of the downward pressing element to seal a gap between the downward pressing element and the filter cup while the downward force is applied evenly to the loose ground coffee in the filter cup, thereby sealing and compacting the ground coffee hydraulically and automatically;
• and
• wherein after coffee is extracted, the delivery system guides the cool water from the extraction apparatus back into the cool water tank, and consequently the sliding element and the downward pressing element are moved upward to original positions thereof to unseal the filter cup, whereby the automatic extraction apparatus performs the sealing and the compacting rapidly and uniformly.