US2222216A

US2222216A - Refrigerant distributor

Info

Publication number: US2222216A
Authority: US
Inventors: Joseph D Lear
Original assignee: Fedders Manufacturing Co Inc
Current assignee: Fedders Manufacturing Co Inc
Priority date: 1937-03-04
Filing date: 1939-02-14
Publication date: 1940-11-19
Anticipated expiration: 1957-11-19

Description

Nov. 19, 1940. J. LEAR 2,222,216

REFR I GERANT DI STRIBUT OR 1 Original Filed March 4, 1937 INVENT R M BZW ATTORNEY Patented Nov. 19, 1940 UNITED STATES REFRIGERANT DISTRIBUTOR Joseph D. Lear, Buifalo, N. Y., assignor to Fedders Manufacturing Company, Inc., Buffalo, N. Y.

Original application March 4, 1937, Serial No. 129,019. Divided and this application February 14, 1939, Serial No. 256,273

6 Claims.

This invention relates to refrigeration systems, and it has particular reference to the rovision of means for distributing liquid refrigerant to a plurality of expansion coils.

The invention is applicable in systems where a plurality of separate refrigeration coils are'supplied from a. single source through an inlet manifold, and it consists of a distributor which apportions the refrigerant supply to the feed conduits which lead to the several coils. In the embodiment of the invention illustrated herein, there is provided a unit with a plurality of ports which, through valve structures, may be varied to suit the demands of the several coils. Undesirable inequalities or equalities of feeding may therefore be eliminated.

The invention is more specifically described in the accompanying specification, reference being had to the drawing, wherein:

Fig. 1 is a side elevation of a distributor unit with portions shown in vertical section. An associatedrefrigerant coil unit is shown diagrammatically.

Fig. 2 is a plan thereof.

Fig. 3 is an enlarged fragmentary section on the line 3-3 of Fig. 1.

Fig. 4 is a side elevation of a control valve.

In Fig. l a feed or distributor unit I is shown organized with a refrigerant evaporator unit I l of a well known type consisting of finned tube coils l2, l3, l4, vertical rows and having inlet'or feed tubes 12a, l3a, Ila, l5a, Ilia, Ila leading to the control unit Ill. The outlet terminals of the coils lead to a common discharge header I 8, which communicates with the suction sideof a refrigeration system through a suction pipe 20,

The unit H is mounted in an air duct 2!, and the stream of air which is forced therethrough passes through the successive coil structures and is progressively. cooled to the desired temperaill ture. As is well known in the art, the first coil l1 impinged by the air bears the heaviest refrigerating load, which load isdiminished progressively in thesucceeding coils, and accordingly the coils will require a directly proportional supply of refrigerant, which, in the present invention, is accurately metered to the-feed tubes through the distributor unit III.

50 is fitted over and brazed to the upper flange 23.

l5, l6, 11, disposed in parallel The unit [0 includes a housing fabricated of The open end of the shell is subsequently spun over and brazed to the lower flang 24, as indicated by the numeral 28, to form a sealed annular reservoir or compartment 30 about the body 22. The reservoir is supplied with refrigerant 5 through an inlet pipe 29 which is fitted in a drilled inlet boss 3| in the flange 24. The pipe may lead to any of the well known control valve units used in refrigerationsystems for controls ling the quantity of refrigerant directed to the coils. j For exemplary purposes, a thermostatic expansion valve V is shown interposed in the pipe line 9.

The body is drilled to provide six equally spaced -vertical formations, each comprising an opening 18 33 for receiving one of the feed tubes, a communicating vertical valve chamber 34, a valve stem opening 35, and a tapped hole 36. The body is slotted to provide elongated vertical ports 3"! each leading into a valve chamber 34, and thus pro- 20 viding communication between the reservoir and the feed tubes of the evaporator unit Ii.

The port areas are controlled by manually operable valve devices which may be of any of the numerous forms known in the art. I prefer, how- :5 ever, to utilize a cylindrical valve 40, which is formed with a flattened side 4|. Each valve is rotatably mounted within a valve chamber 34 and it is formed with astem 42 of reduced diameter which projects through the opening 35. 30 The tapped hole 36 receives a nut 43 which retains a packing ring 44 in tight engagement with the stem 42, and thus prevents gas escape about the stem. The projecting portion of each stem receives an operating handle 46 which overlies u an escutcheon plate 41 which. is soldered to the end 21 of the shell 25. The plate 41 is formed with dial markings 48 for each handle 46 to indicate the open and closed position of the valve.

When it is possible to place the unit I0 above the level of the coil unit H, I have found it advantageous to reduce the head pressurein the reservoir 30 and valve chambers 34, so that a. close simulation of a gravity feed through the valves is obtained. This is eifected by providing a diametricai hole 50 in the body 22, which communicates with the upper extremity of the reservoir 30. This hole communicates with a vertical hole 5| which receives a gas escape tube 52 leading to the discharge header l8. Thus, gases r accumulating in the reservoir 30 are discharged directly into the header l8, and accordingly the pressure in the reservoir is reduced so that a gravity flow of the liquid refrigerant is obtained. .In .othertypes of installations, it may be d sirr nevertheless permits'of independentsetting of It will be apparent that after a preliminary setting of the valves on the basis of the computed capacity of the various coils, a more accurate setting thereof may be obtained by observation of the sweat or dew points on the coils, so

that under constant air flow conditions the coils may operate with maximum efliciency. In the drawing, the'valve of the last coil 12 is closed, so that the coil is rendered completely inoperative, while the remaining coils, starting with the coil H, are supplied with progressively diminishing volumes of refrigerant. Thus, not only may the coils be supplied with precise volumes of refrigerant, but any desired number of coils may be shut down when the operation of the system under a reduced load is deemed economical.

The structure of the valves and ports is such that the refrigerant escapes from the reservoir 30 through narrow, vertical slits, and, as a result, the liquid refrigerant will continue to rise in the reservoir until it attains a level where the covered port areas are substantially equal to the orifice area of the escape port of the thermostatic expansion valve V, which supplies the reservoir. In view of the proportional characteristics of the port openings, it will be apparent that even if the unit III is installed a few-degrees out of a true vertical position, the error reflected on the ports will be extremely small.

The applicability and value of the invention will be apparent by considering the conditions which arise in feeding refrigerant to a plurality of coil passages from a common source. tofore, it was customary to provide each coil passagewith its own thermostatic expansion valver Due, however, to initial cost, andvthe difficulty of balancing-a large number of thermo-' static valves against eachother, this method has met with universal criticism. Recourse was then made to static distributors connected between the coil passages and the discharge side of a single valve. The object of a substantial number of designs along this line has been to equalize the flow .of refrigerant to each coll,- thus,'i1 there were six coil passages, the distributor would be provided with six equalsized discharge ports. 4

. However, experience hasshown that this proposal does not give the results desired. One reason is that a. flowing and boiling mass of refrigerant will not.readily divide itself uniformly in passing through a number of simple oriflces, such as holes drilled in a plate. Another reason is that many' coils .arer'so installed that the. heat load on one section is not equal to the heat load on another, and therefore absolutely uniform distribution of refrigerant, if obtained in the flrst instance, would not be wanted. When-.

. ever the quantity ofrefrigerant is divided and proportioned improperly with respect to the heat load on the several coils, the coil efliciency must be reduced to the effectiveness of the most inemcient section, to avoid flooding of the com- The necessity for independent thermostatic valves,

7 the several ports leading to the coil sections,

after the unit isinstalled. By observing the degree of superheat on the suction side of each unit, and adjusting the valve handles 4' as ing 2,222,210 able to reduce the eifective area of the tube 52 Here-- present invention, while the dicated, each coil section may then be brought to the same degree of eifectiveness, and irregularities due to variations in internal resistance, port apertures, and coil loading may be compensated for.

The present application is a division of my copending' application Serial No. 129,019, filed March 4, 1937. It will be understood that while the invention has been described with reference to a single embodiment, its novel and useful features may be embodied in other forms and arrangements, and therefore it is intended that the scope of the invention should be determined by reference to the following claims.

"I claim: I

l. A distributor device for supplying refrigerant to a plurality of cooling coils comprising a housing including a compartment connected to a'refrigerant supply source, a plurality of vertically disposed valve chambers in the housing, one end of each chamber being connected to a feed conduit for a cooling coil, vertical ports in the housing connecting each chamber with said compartment, an elongated valve in each chamber disposed therein to control the port area, each valve having a stem extending through the housing and supplied with an adjusting lever.

2. A distributor device for supplying refrigerant to a plurality of cooling coils comprising a housing including a compartment connected to a refrigerant supply source, a plurality of vertically disposed cylindrical valve chambers in said housing, one end of each chamber being connected to a feed conduit for a cooling coil, a vertical slot in the housing entering each chamher and constituting ports for connectingthe chambers to said compartment, a cylindrical valve rotatably mounted in each valve chamber and formed withan axial flattened side, each ,valve having a stem extending through thehous ing and supplied with an adjusting -lever.

3. A distributor device for supplying refrigerant to a plurality of cooling coils comprising a.

housing including a compartment connected to a refrigerant supply source, a pluralityof vertically-disposed cylindrical valve chambers in said housing, one end of each chamber being connected'to a feed conduit for a cooling coil, a

"vertical slot in the housing entering each chamher and constituting ports for connecting the chambers to said compartment, a-cylindrical valve rotatably mounted in each valve chamber and formed with an axial flattened side, each valve having a'stem extending through the housing and supplied'with an adjusting lever, and indicia groups formed on the exterior of the housing for cooperation with each lever.

4. A distributor device for supplying refriger-' ant to a plurality of cooling coils comprising a ,vertically disposed bodyhaving a --circular ra-' dial flange on its lower extremity and a cup shaped shell having an opening inits end wall through which the upperextremity of the body projects, the remainder of the shell enclosing the body with the open end of the shell secured to saidflange, a plurality of vertically dis valve chambers in said body, the lower end of each chamber being connected to a feed conduit for a cooling coil, said body being formed with vertical port slots each establishing communication between a chamber and the space enclosed by the shell, an elongated valve in each chamber disposed therein to control the port meaehvalvehavingastcmextendingthmugh the body and supplied with an adjusting lever.

5. In a refrigeration system having a plurality of independent cooling coils and a refrigerant supply conduit including an automatic control valve therein, -a distributor comprising a housing adapted to receive volumes of refrigerant from said conduit under control of the control valve, a plurality of discharge ports formed in the housing, each of said ports being adapted to be connected to supply one of said cooling coils, and independently adjustable valve means for varying the elfective opening of eachyof said ports so that refrigerant supplies to the housing may be selectively apportioned to the coils.

6. In a refrigeration system having a plurality of cooling coils and a refrigerant supply conduit including an automatic control valve therein, a distributor comprising a housing adapted to receive volumes of refrigerant from said conduit under control of the control valve, distributor conduits communicating with the housing and each being adapted for connection to one of the coils, port means in the housing for admitting refrigerant from the housing to each of the conduits, and manually adjustable valve means for controlling the proportionate quantity of refrigerant passing through each of said port means into said coils, whereby by manual setting of said valve means the quantity of refrigerant supplied to the housing by the automatic control valve may be proportioned to the heat load on each coil and to the total quantity of refrigerant thus supplied.

JOSEPH D. LEAR.