Patent GB-270321-A (GB)
Title: Improvements in or relating to absorption refrigerating apparatus containing a pressure equalising medium
IPC: F25B15/10
Filed: 1927-04-29
Abstract: 270,321. Electrolux, Ltd., (Assignees of Platen-Munters Refrigerating System Aktiebolag). May 1, 1926, [Convention date]. Refrigerating, absorption processes for. - In continuous-cycle systems containing a pressureequalizing inert gas, periodical changes of pressure or volume give rise to oscillations of an element to effect a circulation of the gaseous or liquid medium in the system. The element may comprise solid piston members or a column of liquid in a U-tube. A diagrammatic view of means for circulating the mixture of refrigerant and inert gas and the inert gas between the absorber A and evaporator G is shown in Fig. 3. A pipe R, connecting the upper parts of the absorber and evaporator is fitted with a valve 1 opening under excess pressure towards the absorber, while a pipe R<2> connecting the lower parts is fitted with a valve 2 opening towards the evaporator. Pipes R<1>, R" connect from either side of the valve 2 with the limbs of a U-tube U containing a liquid such as ammonia solution. It is assumed that hydrogen circulates as the inert gas between the absorber and evaporator. When liquid ammonia enters the evaporator it evaporates into the hydrogen and the volume increases, causing the level to sink in the right hand limb of the U-tube, and when the pressure increases the valve 1 opens suddenly, allowing a mixture of hydrogen and ammonia to flow into the absorber and causing the liquid in the U-tube to sink in the left hand limb and suck hydrogen from the absorber. At the next oscillation in the first direction this hydrogen is delivered to the evaporator through pipe R<1> and valve 2. Preferably the left limb of the U-tube narrows gradually to the top, while the right limb is parallel. In a modification, pressure variations of the refrigerant medium passing through a loaded valve to the condenser cause oscillations of mercury and liquid ammonia columns respectively in U-tubes connected with the absorber and evaporator. In another arrangement, shown in Fig. 5, a U-tube U connected between the absorber A and evaporator G has a narrowing left limb, and liquid seal devices 2, 6 take the place of mechanical valves. Gas mixture flows through the pipe 6 and forces strong liquor from a chamber up pipes 9, 10, until eventually the pipe 9 is open for flow of gas, which then passes through the pipe R, to the absorber. Liquor conveyed through the pipe 9 into a cup 10<b> at the top of the pipe 10 may be led back to the generator by a pipe 12, the device acting as a heat pump. Pipes 5, 8, 11 connect the lower part of the absorber with the liquid seals and the evaporator. The Specification, as open to inspection under Sect. 91 (3) (a) comprises also the following :- In an arrangement, shown in Fig. 5 (Cancelled), for use with a low-pressure refrigerant such as tri-ethylamine, the valve 1 is arranged in the pipe R1 from the generator to the condenser, and pressure changes in the generator act through a column of mercury in a tube R upon a confined body of hydrogen in a divided chamber J. Changes of volume of the hydrogen cause changes ;n the position of a mercury column in a coiled pipe R8 and chamber S, and ultimately an oscillation of connected columns of liquid triethylamine in vessels L, K, whereby a gas circulation in the absorber A and evaporator G is effected. This subject-matter does not appear in the Specification as accepted.