An upper piston and a lower piston are arranged in the housing.

The lower cylinder is adapted to receive the lower plunger and the upper cylinder is adapted to receive the upper plunger.

The plunger assembly includes a lower pressure chamber, an upper plunger element, and a lower plunger element.

The plunger assembly includes concentric upper and lower plunger sections interconnected by a double-valve, ported valve cage.

The reservoir unit (20) has a piston assembly (70) with a top piston (72) and a bottom piston (74).

An upper piston (7) is secured to a frame (1).

The piston assembly includes a driving cable connecting a top leaky piston and a bottom leaky piston having a check valve connected thereto.

An upper piston slides in an upper chamber in contact with a pushrod.

An upper piston (9) and a lower piston (10) are respectively provided in the upper cylinder(6) and the lower cylinder (7), and the two pistons are connected together by a connecting rod(11).

The upper piston assembly includes a dispensing tube (141) that engages a channel through the piston to accommodate dispensing the brewed liquid.

The mechanical valve actuator includes an upper piston, an upper diaphragm, a pilot piston with a bore and a plunger, and a spring.

The plunger material (48) at the top, is in the form of tamping.

The press has inner and outer lower punches, and an upper, outer punch.

The existence of the intermediate segment inside the cylinder of the 'DOUBLE EXPLOSION PISTON' makes the bottom piston work in a four-stroke cycle also, ensuring identical performances as the upper piston.

The spring is positioned either inside the pilot piston for the normally open valve or inside the upper piston for the normally closed valve.