GB527331A - Improvements in apparatus and process for making infusions - Google Patents

Abstract

527,331. Infusion apparatus. NOWLAND, R. L. April 6, 1939, No. 10777. Convention date, April 9, 1938. [Class 129] The filling aperture of an electrically-heated boiling-chamber 2 is closed by a locked-down lid 8 having fixed thereto a depending tube 5 which, at its upper end and outside the chamber, supports a teapot 1 by engaging in the manner of a ball and socket joint the lower end of a rising tube 7 fixed in the teapot. A tea leaf basket 4 is supported on a shoulder 28 of the tube 7 and has a tubular core 31 which in effect extends the rising tube. A glass bell 3 is inverted over the basket and extends down into the teapot where it is formed with two holes 35 the upper one of which may be closed by a sliding spring leaf 39. In operation, when boiling point is reached, the water is forced up the tube to the top where it descends through the tea leaf basket 4 and the glass bell 3 into the teapot 1 ; the liquid rises in the teapot and covers the holes 35 in the side of the bell 3. The heating unit is cut out as soon as the water in the boiling chamber 2 falls below the bottom of the tube 5 since a bimetallic strip which is housed in a pocket 50 then uncovered by the water, experiences a substantial rise in temperature and a contact in the heater circuit is opened. On cooling, a partial vacuum arises whereby the liquid rises inside the bell 3 and covers the tea leaf basket 4. The liquid of course falls at the outside of the bell and when the topmost open hole 35 is uncovered some air flows into the bell to agitate the liquid, some liquid flowing out so that the hole is again covered. This action recurs as the cooling proceeds. When the infusion process is considered to have been sufficient a valve 25 on the boiling chamber is opened to destroy the partial vacuum whereby the liquid inside the bell 3 drops away from the tea leaf basket. The teapot is then lifted off the boiling chamber and used in the ordinary way. The usual small vent 26 in the rising tube 5 is located in recessed portion 27 of the lid 8 so as to be above the level of the filling aperture of the boiling chamber which has corrugations 44 to serve as gauge marks. The bell is held in position by spring fingers 36.