Patent GB-354720-A (GB)
Title: Improvements in or relating to refrigeration apparatus
IPC: F25B49/04
Filed: 1930-03-10
Abstract: 354,720. R e - frigerating. SILICA GEL CORPORATION, 1800, Baltimore Trust Building, Baltimore U.S.A.- (Assignees of Miller, E. B.; Baltimore, U.S.A.) March 10, 1930, No. 7803. Convention date, March 14, 1929. [Class 29.] Vacuum systems.- The adsorber of a system employing silica gel or like solid medium as adsorbent and a condensible refrigerant such as SO2 is arranged within a heat-insulated casing fitted with dampers adapted to be closed during the activatingor generating period and opened for circulation of cooling air during the adsorption period. A fan fitted within the casing produces an internal circulation of the heated air during the heating period and a through draught of cooling air during the adsorption phase. The motor driving the fan in the adsorber casing also drives means for circulating air or other cooling fluid over the condenser. The dampers may be actuated by the means actuating the fuel supply valve. Preferably the valve is actuated by an electric motor controlled by a timing mechanism with overriding controls by a thermostat in the cooling chamber and by high and low temperature safety devices for the burner. The refrigerating system as shown schematically in Fig. 1 comprises the adsorber 18 in the casing 30, a condenser 27, a receiver 29, and an evaporator 11 in a cold storage space 10. The evaporator may comprise a drum 13 with depending pipes 12 and a float inlet valve 14. The adsorber comprises tubes 19 filled with the adsorbent, the tubes being sealed at their lower ends and passed through plates damped together. The upper ends connect with sub-headers 20 and main headers 21, and the assembly is supported by angle-iron members 111, Fig. 3, recessed in the sides of the casing, which may be formed of asbestos boards bound by angle frames mounted on legs 102. The tube block occupies the full front-to-back depth of the casing, but is enclosed by plates 112, Fig. 4, spaced from the 'sides of the casing to provide air-circulating passages. The dampers 42, 45 are hinged, and open upwards. Deflector plates 135, 135<1> are fitted to the lower dampers and to the casing respectively, so that the heated air circulated down the side passages by the fan 34 is deflected away from the flame of the burner 118. The burner is fitted with a baffle 115 and a gauze flame spreader 113, and is ignited by a climbing jet 128, Fig. 3, with a separate fuel supply, leading into the casing 126 of a pilot light. The fan 51, Fig. 1, circulating air over the condenser is shrouded by plates 50 serving as deflectors for the air currents from the adsorber casing. The connecting pipes 143, 144, 148, Fig. 3, between the condenser, evaporator, and adsorber lead to a common valve casing 140 containing two check valves and three manually-actuated valves. The timing device is housed in a casing 166 and the burner valve and damper actuating means in a housing 131. The refrigerant receiver may be located below the adsorber, as shown at 136, Fig. 3. The fuel valve 38, Fig. 1, may be opened and held open against the action of a spring 73 by an electric motor 63. The fan motor 44 and the valve motor are supplied from leads 60, the valve motor circuit being controlled by a switch 64 governed by a thermostat 67 in the cold room, and by a timing switch 69. The valve motor shaft carries a pinion 70 gearing with a rack 71 on the valve spindle, and when the motor circuit is open the spring 73 closes the valve and turns the motor backwards. The spindle is connected by lever and link mechanism 90, 89, &c. to the dampers. In a modification the fuel valve is actuated by an electromagnet, the circuit of which is controlled from timing mechanism driven by the fan motor. This mechanism, Fig. 10 (not shown), includes Geneva stop gear, and actuates the dampers separately. The dampers may be actuated by a separate motor, the circuit being arranged as shown in Fig. 11. Current is supplied from leads 215 through a thermal switch 216. The fuel valve motor 204 is in shunt to the fan motor 217 and is controlled by a switch 218 of the tilting mercury type on a rocker 220 actuated by the timing motor 201. The damper motor 222 drives the shaft 208 through reducing gear, and a rotatable contact arm 225 on the shaft is moved over arcuate contacts so that it breaks the circuit after a half revolution of the shaft. The threecontact mercury switch 221 of the damper motor is carried on the rocker 220.