GB255035A - Improvements in or relating to absorption refrigerating machines - Google Patents

Abstract

255,035. Munters, A. J. June 15, 1926. Refrigerating, absorption machines for.-In a continuous-cycle system the circulation is regulated by a, slide valve or like member actuated mechanically by a piston operated by the fluid of the system. The system comprises a generator 1 heated by an electric heater 71, a rectifier 3, condenser 2, evaporator 4, absorber 5 and a heat exchanger 6 connected in a closed cycle. The control and circulating means is housed in a member 8, having a cover member 14 through which the various pipes are connected, and comprises a small piston 11 adapted to move downwards under the pressure of liquid refrigerant admitted to its cylinder 47 from the condenser, the lower end 21 of the piston 11 and the upper end 22 of a larger piston 12 being engaged in a, forked member 20 extending laterally from a carriage 24 adapted to release rocking pawls from ported flat slide valves 16, 17. The lower piston is moved upwards by liquor flowing into the cylinder 48 from the boiler to the absorber, while the flow into the generator takes place through a bottom chamber 58, under the control of the lower slide valve. The slide valves may be rigidly connected, but in order to reduce friction are preferably in two parts with engaging projections and notches 18, 19, Fig. 2. As the pistons 11, 12 move downwards, a spring 28 housed within the carriage is compressed, until the upper locking-pawl 36 is tripped by a pin 42, when both slide valves are moved down suddenly. A similar action occurs on the up-stroke of the pistons. With the parts in the position shown, condensed refrigerant flows through a pipe 51, port 50 and passage 72 to the cylinder 47, and weak liquor flows from the lower cylinder 48 through a port 53 and pipe 58 into the upper part of the absorber 5. The bottom chamber 58, which has previously been charged with strong liquor from the absorber, is open to the gas space of the generator through ports 55, 56 and the liquor flows from the chamber into the generator. In the reversed position of the valves the cylinder 48 is open through a passage 73 to liquor from the interchanger 6 at the pressure of the generator, and the cylinder 47 is open to the evaporator through a port 49. The chamber 58 is then closed to the generator and open to both ends of the absorber. The pressure of the liquor in cylinder 48 raises the pistons, a spring 46 around the upper piston acting as a buffer, and the carriage 48 trips the lower pawl. The rate of flow of liquor, and therefore also of refrigerant, is adjusted by a screw throttling member 77 controlling the passage to the cylinder 48. Or a dashpot arranged below the piston 12 may be employed. The slide valves are packed around the ports and passages 65, Fig. 7, by annular metal discs 63 pressed against the slides by rubber or like discs 66, the metal discs having projecting ribs 67 embedded in the rubber. The control arrangement described necessitates the location of the chamber 58 above the level of the liquid in the generator, but in a modification the. chamber 58 may be replaced by a cylinder containing a differential piston whereby the liquor may be pumped into the absorber and generator. The piston may actuate the slide valves through spring gear in the manner above described, in which case the upper pistons may be dispensed with, the liquids being circulated through chambers put into communication alternately with high and low pressure sources.