US3020729A

US3020729A - Valve for refrigerating medium evaporators

Info

Publication number: US3020729A
Authority: US
Inventors: Brandin Johan Axel Ivar
Original assignee: Individual
Current assignee: Individual
Priority date: 1958-01-13
Filing date: 1958-12-30
Publication date: 1962-02-13
Anticipated expiration: 1979-02-13

Description

Feb. 13, 1962 J. A. l. BRANDIN 3,020,729

VALVE FOR REFRIGERATING MEDIUM EVAPORATORS Filed Dec. 50, 1958 C EXPANSION L QU/D ONDENSER VALVE SEPHRA roe Fly. 1

' HOT 6445 F0]? 5 FFE C T lNG DEFFOST/NG COMPRESSOR smpaenrok FLOW OF esFe/ssenA/r DUEI-5 F255 Z/NG PER /00 FLOW 0F BEFEIGEEHNT OUR/N5 9 ST/NG FEE/o0 -9- United States Patent 3,020,729 Patented Feb. 13, 1962 ice 3,020,729 VALVE FOR REFRIGERATENG MEDIUM EVAPORATORS Johan Axel Ivar Brandin, Hogalidsvagen 8, Finspong, Sweden Filed Dec. 30, 1958, Ser. No. 783,816 Claims priority, application Sweden Jan. 13, 1958 Claims. (Cl. 62-218) In certain types of refrigerating medium evaporators and more particularly in so called tube ice generators an ntermittent defrosting is required at comparatively short intervals. Said defrosting operation is effected, as a rule, by expelling the liquid refrigerating medium from the evaporator by means of a hot gas derived from the high pressure side of the refrigerating system. In order that the defrosting operation may be rapid and efficient, the pipe through which the liquid is expelled from the evaporator should be blocked up at the very instant when all the liquid is removed from the evaporator.

The present invention has for its object to provide a valve for use in connection with a refrigerating medium evaporator with a View to automatically blocking up a refrigerating medium pipe after the refrigerating medium is expelled from the evaporator in connection with a defrosting operation.

The invention is characterized, chiefly, by the provision within a receptacle having inlet and outlet pipes for the refrigerating medium, of an open basin which, when the refrigerating medium has been expelled from the evapo rator, raises and blocks the pipe through which the refrigerating medium is expelled from the receptacle.

The invention is illustrated by way of example in the accompanying drawing in which,

FIG. 1 is a longitudinal section of a receptacle with the valve in open state and FIG. 2 is a similar section with the valve in closed state.

In the drawing, the numeral 1 designates a closed receptacle for a refrigerating medium, said medium being supplied to the receptacle during the cooling periods through a pipe 2 from a receiving container, which is situated on a level above that of the evaporator of the refrigerating plant. From the receptacle 1 the refrigcrating medium is passed to the evaporator through two symmetrically arranged

pipes

3 and 3. Provided below

pipes

2 and 3 is a valve in the shape of a basin 4 the concave surface of which faces said pipe. Said basin is supported by a set screw 5 and to this end the bottom of the basin is formed with an upstanding sleeve shaped portion 6 into which the upper end of the set screw projects. The set screw is threaded at 7 and engages by its threaded portion a nut shaped sleeve 9 rigidly inserted in the bottom of the receptacle 1. Thus, by adjusting the screw 5 the distance between the basin and the pipes may be varied. The numeral 8 indicates a pipe for condensate.

During the cooling periods refrigerating medium is supplied to the evaporator from the refrigerating medium container through pipe 2 and withdrawn through pipes 3 in the position of basin 4 shown in FIG. 1, so that the receptacle 1 is completely filled with refrigerating medium. When the evaporator is to be defrosted (including, for instance, removal of icicles from the tubes of an ice machine) a hot gas is admitted to the evaporator from the high pressure side of the refrigerating machine, said gas expelling the refrigerating medium from the evaporator through pipes 3, receptacle 1 and pipe 2 up into the refrigerating medium container at a high velocity. In this operation due to the Venturi effect of fast moving liquid, a vacuum will exist at the entrance of pipe 2, said vacuum tending to raise the basin 4, thereby causing it to close the inlet of pipe 2. In order to counteract this tendency the basin so that the streams of liquid therethrough will be directed towards the basin, thereby keeping the basin in its open state as long as liquid is discharged from pipes 3. A suitable adjustment of the position of the basin when open may be fixed by means of the set screw 5. By the provision of two pipes 3 symmetrically positioned with relation to the basin 4 the basin may be symmetrically acted on by the liquid streams.

After the evaporator is emptied of liquid and a gas is allowed to enter the receptacle 1, the basin 4 will move upwards until it closes the inlet of pipe 2. Said closing action is caused, in part, by the fact that the gas is not in the same way as the liquid supplied through pipes 3 capable of counteracting the vacuum as caused by the entrance of the refrigerating medium into pipe 2 and, in part, due to the fact that a difference in pressure will appear because there is a liquid below the basin and a mixture of gas and liquid above the basin. Due to the difference in specific weights which exists between said two fluids the basin will be subjected to a raising or floating power. The position shown in FIG. 2 will result very rapidly as soon as gas enters into the receptacle 1.

During the defrosting operation any condensate re sulting will be discharged from the evaporator through pipes 3 and delivered to the basin from where it is withdrawn through pipe 8 and delievered to the refrigerating medium container.

After the defrosting operation is ended and high pressure gas is no longer supplied to the evaporator, the pressure prevailing inside the receptacle 1 is reduced, allowing the basin to drop under the combined action of the weight of the liquid in pipe 2 and its own weight.

I claim:

1. A valve for use in a refrigeration system in which, during defrosting periods warm ga is caused to flow through the evaporator of the system in the direction opposite to that in which the cooling medium flows during a refrigeration period so that the liquid cooling medium is driven from the evaporator during the defrosting period and stored in a receiving container connected in a conduit between the condenser and evaporator of the refrigeration system, comprising a closed receptacle connected in conduits between the receiving container and the evaporator, said closed receptacle having an upwardly open basin-shaped valve located therein and freely movable in the vertical direction, the conduit between the evaporator and said closed receptacle extending into said basin-shaped valve in the downward direction and having egress means arranged symmetrically with respect to the center of said basin-shaped valves, the imaginary plane extending through said agress means being parallel to the bottom of said basin-shaped valve, said valve in its uppermost position closing the conduit to said receiving container, while leaving a small play between itself and the egress means of the conduits leading to the evaporator.

2. In a valve as claimed in claim 1, the further feature that the conduit connecting said closed receptacle to the, receiving container has its bottom end located centrally with relation to the basin.

3. A valve as claimed in claim 1, and in which the conduit connecting said closed receptacle to the refrigerant receiving container opens centrally above the basin, and the egress means of the conduits connecting said closed receptacle to the evaporator of the system is comprised of a plurality of downwardly directed open ends positioned symmetrically on opposite sides of said cen trally positioned conduit end.

4. A valve as claimed in claim 1, and in which means are provided in combination with the closed receptacle containing the basin for adjusting the distance between References Cited in the file of this patent UNITED STATES PATENTS Mojonnier May 18, Stiren Aug. 26, Schliemann Aug. 4, Kellog Oct. 13, Philipp June 1, La Porte Jan. 4,