Patent GB-847933-A (GB)
Title: Machine for the preparation of coffee infusion
IPC: A47J31/30
Filed: 1956-11-15
Abstract: 847,933. Coffee making machines. FORGHIERI, R. Nov. 15, 1956 [Nov. 18, 1955; Oct. 9, 1956], No. 34965/56. Class 129. [Also in Group XXIX] A coffee making machine comprises one or more distributers to which hot water under high pressure is supplied from a single conduit containing water under pressure, means being provided for heating the water before it reaches the distributers and one or more pressure compensators communicating with the distributer or distributers to avoid sudden drops of pressure when the distributing cocks are operated. As shown distributers operated by handles 2 have seatings 3 for cups carrying coffee filters. The distributers are fed by a tube 5 connected to the upper end 6 of a conduit 7 enclosed in insulating coverings 8 e.g. constituted by panels consisting of metallic casings filled with insulating material. Underneath the conduit there' is a small pipe 14 connected to gas or the like and feeding burners to heat the conduit. Water under pressure above that of the mains is supplied to conduit 7 and a pressure compensator 16 is provided to avoid abrupt changes in pressure when water is delivered through the distributers. Tank 16 has an internal chamber in which all the air collects when conduit 7 and tube 5 are filled with water and the air acts as a cushion and absorbs variations in pressure. A separate steam supply device is connected to the end of tube 5 and comprises a tube 21 which enters tube 5 and is closed at its one end by a plug 22 its free end carrying an expansion chamber 25. A small tube 26 connecting tubes 21 and 25 has a valve 27 through which water may pass into tube 21 and chamber 25 where it boils to produce steam which is carried away in a flexible pipe attached to fitting 30 to a distributer. In an alternative arrangement, Fig. 5, a conduit 31, fed from a supply tank, is connected by a series of liquid tight connections to a series of tubes 36. The other end of each tube 36 is connected by a further liquid tight connection to a body 39 of a cock in which there is a bore 43 connecting tube 36 to tube 44 whose upper end enters pressure compensator 45 mounted on top of body 39 by means of a fitting 46 whose bore 51 surrounds tube 44. Compensator 45 contains an electric heating element 53 controlled by thermostat 56. Alternatively element 53 may be placed in conduit 31. Bore 51 leads to a bore 52 which opens into a cylindrical cavity 58 from which a conduit 75 leads to the coffee filter. An annular packing 59 surrounds the opening of bore 52 and a cylinder 60 locates packings 63 in cavity 58. A cylinder 64 slides in cylinder 60 and has a plug 64 which engages packing 59 to stop flow of liquid from compensator 45 to conduit 75. A spring 66 is contained in cylinder 64 and a cylinder 67 sliding therewithin whose end has a tail 68 which engages a cam 70 moved by a lever 71. In the solid line position the water pressure is sufficient to push plug 65 away from packing 59 so that water reaches conduit 75 whereas when in the dotted line position plug 65 is held against packing 59. If there is an exceptional rise of pressure in compensator 45 plug 65 will be pushed against the action of spring 66 even with the cam in this position to relieve the pressure.