GB780996A - Improved machine to prepare coffee as a drink - Google Patents

Abstract

780,996. Coffee making machines. EGI, M., FIORENZATO, P., and NOVI, I. Dec. 1, 1954 [Dec. 2, 1953; Aug. 14, 1954], No. 34802/54. Class 129. [Also in Group XXIX] A machine for preparing coffee comprises a drum 20 rotatably supported in a fixed casing 10 which has, angularly spaced in the direction of rotation of the drum, an opening for introducing ground coffee, an outlet opening, with a perforated diaphragm 30, for the prepared beverage and a discharge opening for the used coffee, the drum having at least one radial cylinder 21 which can be placed successively in communication with the openings and contains an apertured piston 24 with a perforated diaphragm 25 at its outer end. Means are provided for supplying hot water and steam firstly to the cylinder in the drink preparing position to compress the coffee grounds between the diaphragms 25, 30 and prepare the beverage and secondly in the ground discharging position to eject used grounds. As shown, drum 20 has three equally spaced cylinders 21 between which there are cavities 22 into which hot water or steam is introduced through passages 23. When one cylinder 21 is situated adjacent the outlet opening, from which an extension 29 projects carrying an outlet tap 11, the other two cylinders will be adjacent respectively to an upper mouth 26 leading to a storage container and a grinding device and to a discharge opening 27. Extension 29 is secured to a tubular extension 43 of casing 10 by an internally screw-threaded ring. A body 42 axially slidable within extension 43 has within it a further axially slidable body 40 with a central bore 41. Body 40 supports diaphragm 30 and body 42 carries an annular seal 44 which engages the surface of drum 20 and the two bodies are connected by a pivot system 45 mounted in a block 46and biased by spring 47 towards drum 20. Thus, when one of the pistons 24 presses the coffee grounds against the diaphragm 30, it presses body 40 down and this pushes body 42 up so that seal 44 engages drum 20. At the same time, hot water is fed to the cylinder adjacent the discharge opening 27 so that the piston pushes the spent grounds into the discharge tube 16. The piston is held in the cylinder by at least one rib 28. The driving system comprises a casing 12 containing a relatively large cylinder 50 and a relatively small cylinder 51 in which reciprocate respectively pistons 52, 53 connected by a rod 54. The pistons are moved upwards by steam entering cylinder 50 through passage 59 and this movement draws hot water into cylinder 51. At the same time a rack 55 formed on an extension of rod 54 engages a toothed wheel 32 mounted on the shaft 31 carrying drum 20 to turn the assembly through 120 degrees. A ratchet gear 33 ensures that the shaft 31 is only rotated on the upward stroke of the pistons. Pistons 52, 53 are moved downwardly by steam entering cylinder 50 through passage 60 which pushes the hot water out of cylinder 51 into a duct 34 leading to the cylinder 21 containing the coffee grounds. The supply of steam to the passages 59 and 60 is controlled by a slide valve 56 operated manually by a handle 57. Two of these coffee making units may be mounted side by side and fed by a single boiler.