Patent GB-751946-A (GB)
Title: Method and apparatus for air conditioning
IPC: F24F1/01
Filed: 1954-11-23
Abstract: 751,946. Ventilating apparatus; hollow ceilings. AKTIEBOLAGET SVENSKA FLAKTFABRIKEN. Nov. 23, 1954 [Nov. 23, 1953], No. 33898/54. Classes 20(4) and 137. A method of air conditioning a plurality of rooms in a building comprises supplying, through a pipe system, from one or more central air conditioning plants, individual units in the rooms with a regulated supply of primary injected air at high velocity, mixing it with the required amount of recirculated room air as it passes through the unit, and conditioning a desired proportion of the mixed air, air corresponding to the quantity of primary air supplied to the room being evacuated in a manner known per se. In a central conditioning plant, Fig. 1, fresh air enters an inlet 1, controlled by a damper 2, and passes through a duct 3 to a heat exchanger 36 which is also connected by a duct 4, 14, to a collector 49 for air exhausted from rooms 100 so that the heat and moisture content of the exhausted air can be transferred to the incoming fresh air before being carried away by a duct 22 and forced by a fan'21 through a duct 19 into the outside air. The primary air from the inlet 1 leaves the exchanger 36 through an opening 7 and is directed through ducts 24, 26 to the inlet 27 of an air conditioning plant 33 which consists of a number of sections 28, 29, 31, 32 comprising e.g. filtering, humidifying, cooking, and heating means, If the air exhausted from the rooms 100 is not to be utilized in the heat exchanger it is conducted by a duct 12 from the duct 14 to the exhaust duct 22, dampers 9, 11, being incorporated respectively in the ducts 4, 12 for this purpose. The inlet for the fresh air in this case is lead directly from an intake 16, controlled by a damper 18, through a duct 23 and ducts 24, 26 to the conditioning plant 33. A fan 34 conveys the conditioned air through a duct 38 to one, or more, distribution, and silencing chambers 39. A cooling compressor 41 is connected by means of pipes, not shown, with the cooling elements of the conditioning plant. The exhaust duct 15 communicates with an enclosure 49 formed e.g. by inserting an additional ceiling 50a in a corridor 50, the individual exhaust grilles of the different rooms terminating in the enclosure. Each room unit 47, Fig. 2, comprises a casing 66 which is installed immediately below a window 52, the upper side of the casing being arranged flush with the window sill 53. Room air, passing along the window surface is drawn through an opening 54 into a space 56 formed by a recess in a wall 99 on the rear side 61 of the casing and through an opening 72 into an upper casing compartment 68. Room air can also be supplied to the compartment from one or more openings in the sides or bottom of the casing. Primary air from the plant 33 is supplied to a lower casing compartment 91 through a pipe 89 which consists of two concentric tubes having an airtight space between them for insulation purposes. The part of the pipe 89 in the compartment 91 i.e. the inner pipe is provided with apertures 88 which are evenly distributed around its outer surface for drawing off the outer layer of air adjacent its inner wall so that the reduction in velocity of the air occurs with small losses. The quantity of primary air for each unit is maintained constant, independent of the pressure variations in the pipe 89 by causing the discharged primary air to pass into a chamber 83 through a volume governor comprising one, or more, volume control openings 86 in a wall 84 across the top of the chamber 91. The chamber 83 is equipped with sound trap walls 82, 79, Primary air travels in the direction of the arrows 85, 81, 78, through rows of jet openings 76 and into the mixing chamber 68 where it is mixed with the secondary room air in the proportion of about 2: 1. The mixing chamber 68 is provided with a separate conditioning apparatus 64 which is separated from a by-pass 68a by means of a partition 70c, a movable damper 71 controlling the amount of mixed air entering the conditioning apparatus 64. The treated air is discharged into the room 100 from the casing 66 through an opening 62a. Pipes 93, connected to the coils of the conditioning apparatus 69 are arranged in a space 92 at the bottom of the casing, the space beneath which is covered by a front plate 97.