GB857084A - Apparatus for preparing coffee beverages - Google Patents

Abstract

857,084. Electric coffee makers. STIEBEL, T. H. July 10, 1957 [July 11, 1956(2)], No. 21853/57. Class 39(3). [Also in Group VI] Coffee beverage making apparatus comprises heating means 2 in the lower part of a closed container 1 with control means for turning it off and at the same time, opening a vent valve 25 in the upper part of the container which also has a water inlet pipe 3 and contains a riser tube 5 connected to near the closed top of an outflow pipe 6 and adjacent an aperture 12 therein the open lower end of pipe 6 being beneath the container 1. As shown the heating means is electric and pipe 3 is controlled by a shutoff valve 4. A throttle 7 may be provided in tube 6 whose lower end 8 is of enlarged crosssection to receive a filter 9 with a perforated support for ground coffee 10. Above the water level in container 1 is mounted a pressure regulator 14 comprising, e.g. a flexible bellows 15 with a rigid end plate 16 into which a rod 17 may be screwed to a greater or lesser extent. An armature 18 on the free end of rod 17 spans a pair of contacts 19 in the heating circuit 20 connectible by a manual switch so that, when the pressure in container 1 exceeds a predetermined amount, the circuit is broken but will be completed again if the pressure drops. In operation, container 1 is filled to the required depth indicated on a guage (not shown) below the levels of vent 12 and pipe 13, valve 4 is shut and circuit 20 is completed. When the water in container 1 is boiling, the pressure forces the hot water through pipes 5 and 6 to the ground coffee 10 vent 12 preventing the water from being forced over at a lower temperature. A further switch 21 is connected in the heating circuit which is opened when container 1 is dry and does not re-connect the circuit when the element 2 has cooled down. The vent valve 27 has an electro-magnetic coil 27 in series with a two position switch 28 actuated on opening and closing water inlet valve 29 in pipe 3. The circuit is as shown in Fig. 2 and when valve 29 is opened switch 28 is moved to energize pump 44 to pump water into container 1 and at the same time coil 27 is de-energized to open vent valve 25. In operation, switch 34 is closed manually which energizes coil 38 to close switch 36 and hold the circuit energized when switch 34 is released. When the container has been emptied switch 21 opens the circuits to de-energize the heating coil 2 and open vent valve 27.