GB190304984A - Improvements in Ice Making and Refrigerating Machines. - Google Patents

Abstract

4984. Hodgkin, P. E., and Rigg, J. L. March 3. Ice-making and refrigerating.- Relates to ammonia and like compression machines, and consists in enlarging the valve supplying ammonia to the refrigerating - chamber and regulating it automatically by the pressure in this chamber, also in an arrangement for keeping the quantity of ammonia in the apparatus constant. A compression pump 7, condenser 9, ammonia bottle 5, regulating- valve box 3, and refrigerating- chamber or coil 1 are joined in series by pipes, the ammonia bottle being provided with valves 28, 29, and being readily disconnectable from the rest of the system. The pipe leading to the refrigerating coil from the valve box 3 and another pipe 2<a>, leading from a chamber 20 which controls the valve, both enter a portion of the valve box screened from the main portion by the valve disc 11. The valve stem 13 passes through a stuffing-box in the valve-box casing, and is in line with a pusher 14 reciprocated by a cam and spring. Between the valve stem and the pusher is a distance-piece 18, pivoted to the end of the valve stem as shown, or not. This is joined by an arm to one side 19 of the controlling- chamber 20, and both this side and the opposite side 19<a> are made as diaphragms, the side 19 being movable by the internal and external pressures and the action of a spring on the piece 18, and the side 19<a> being held in a fixed position by the adjustable support 22. In equilibrium, the pressures in the refrigerator and the controlling-chamber are equal. If this pressure is too low the spring 23 pushes the distance-piece towards the controlling-chamber and it is then reciprocated by the pusher and itself opens the valve, which is closed by the pressure of fluid; a spring may also be used for this purpose. When the pressures in the two chambers become high enough, the piece 18 is again pushed out of adjustment. In order to keep the quantity of ammonia in the system constant when it is to be recharged with ammonia, the bottle 5 is charged to a standard height before being replaced, and when the bottle is withdrawn the ammonia in the system is allowed to evaporate entirely. By closing the valve 28, the whole of the ammonia may be pumped into the bottle, when the apparatus is to be put out of action.