US2432859A

US2432859A - Refrigerant flow controlling means

Info

Publication number: US2432859A
Application number: US530263A
Authority: US
Inventors: Franklyn Y Carter
Original assignee: Detroit Lubricator Co
Current assignee: Detroit Lubricator Co
Priority date: 1944-04-10
Filing date: 1944-04-10
Publication date: 1947-12-16
Anticipated expiration: 1964-12-16

Description

Dec. 16, 1947. F. Y. CARTER REFRIGERANT FLOW CONTROLLING MEANS Filed April 10, 1944 IN VEN TOR.

Y E N m T T A 5 H Patented Dec. 16, 1947 2,432,859 REFRIGERANT FLOW CONTROLLING MEANS Franklyn Y. Carter, Detroit, Mich., assignor to Detroit Lubricator Company, Detroit, Mich., a corporation of Michigan Application April 10, 1944, Serial No. 530,263

8 Claims.

This application relates to new and useful improvements in refrigerating apparatus, and more particularly to a system having a multi-pass evaporator and means for supplying refrigerant thereto.

An object of the invention is to provide a novel refrigerant distributor which will feed refrigerant equally to each of the passes or tubes of the evaporator.

Another object is to provide a distributor in which the probability of feeding any vaporized refrigerant to the distributor orifices is reduced toaminimum.

Another object is to provide means for accurately metering the flow of refrigerant'to a multi-pass evaporator so as to maintain the same refrigerated to a substantially fixed extent during compressor operation,

Another object is to provide a photo-electric control forthe feeding of refrigerant to the evaporator.

The invention consists in the improved construction and combination of parts and their cooperative relation to be more fully described hereinafter and the novelty of which willbe particularly pointed out and distinctly claimed.

In the accompanying drawings to be taken as a part of this specification, there arefully and clearly illustrated several preferred embodiments of the invention, in which drawings:

Figure 1 is a diagrammatic view of a refrigerating apparatus showing the electrically controlled refrigerant distributor in longitudinal vertical section and showing the wiring diagram for the photocell control of the distributor, and

Fig. 2 is a diagrammatic view of part of the refrigerating apparatus of Fig, 1 but showing differential temperature responsive means for controlling the distributor.

In the accompanying drawings to be taken as a part of this specification, there are fully and clearly illustrated several preferred embodiments of the invention, in which drawings:

Fig. 2 is a diagrammatic view of part of the refrigerating apparatus of Fig. 1 but showing differential. temperature responsive means for controlling the distributor.

Referring to the accompanying drawing, l designates generally a motor driven compressor having an outlet conduit 2*connected to a reirigerant condenser 3 which feeds through a conduit 4 into a refrigerant receiver 5 from which a liquid line or conduit 8 connects to the inlet passageway 1 of the electric distributor 8. The

5 bottom wall of the distributor 8 is formed by a closure plate or member 9 having a plurality of passageways l0 therethrough equal in number to the passes or tubes of the evaporator to be supplied with refrigerant. Each of the passageways ID has secured and sealed therein a capillary refrigerant feeding tube H which has its other end connected to the inlet of one of the tubes or passes l2 ofthe multi-tube evaporator 13, having the usual suction header l4.' The inlet of the compressor I is connected to the suction header by a suction conduit [5 having intercalculated thereina light transmitting or bullseye portion l6 for the passage of a light beam therethrough from a light source I! which may be the usual electric lighting device forming part of a photo-electric control system.

The distributor 8 has a vertical tubular hollow housing 3 with upper and lower end flanges I9, 20 respectively. Adjacent the upper' end of the housing member l8 there is an internal horizontal partition 2| which divides the housing member into an upper liquid inlet chamber 22 and a lower refrigerant feeding chamber 23. The inlet passageway 1 opens laterally into the chamber 22 which is communicatively connected to the chamber 23 by a valve port 24 in and extending vertically through the central portion of the partition 2|. The top of the chamber 22 is closed and sealed by a casing 25 which is clamped by bolts 26Ito the flange l9. Within the casing 25 there is an electro-magnctic coil 21 surrounding a tubular guide member 28 in which there is reciprocally positioned the stem 29 of a valve member 30 cooperable with the port 24 to control flow therethrough. The valve member 30 carries an armature 3| for cooperation with the coil 21 to open the valve member 30. A light coil spring 32 may be provided within the guide member 28' to urge the valve member toward closed position. The bottom closure member 9 preferably has av flange 33 between which and the flange 20 a sealing gasket or the like 34 may be clamped by bolts 35. The chamber face of the closure member 9 is provided with a cylindrical recess 36"to receive an orifice plate 31 having calibrated orifices 38 there through equal in number to the outlet passageways lll and registering therewith. The side pertions of the recess 36 extend laterally outward to beneath the wall of the housing member I8 so that the plate 3! will be tightly clamped by the bolts 35 in position betweenthe closure member 9 and the housing member I8.

Each of thetubes II and its restricting orifice 38 has a predetermined resistance to refrigerant flow for a given compressor suction pressure and a given refrigerant pressure in the feeding chamber 23 for a given load on the evaporator I3. The valve port 24 is therefore made sufficiently large so that in the wide open position of the valve member 30, the effective flow area through the port 24 will cause a minimum drop of pressure from the liquid head pressure in theinlet chamber 22 and the pressure in the feeding chamber 23. By reason of the predetermined restriction to flow afforded by the orifices 38 and tubes II, the pressure drop across the port 24 may be restricted to several pounds so that the pressure drop across the port 24 will not lower the pressure below or appreciably below a pressure corresponding to the saturation temperature of the liquid refrigerant supplied to the inlet chamber 22. The condenser 3, as is common in the refrigeration art, will cool the refrigerant somewhat below its saturation temperature as a factor of safety to eliminate gasifying of the refrigerant during its flow or passage through the liquid supply line 6. It is this usual cooling of the refrigerant below its saturation temperature which makes possible the discharge into the feeding chamber 28 of liquid refrigerant with little or no vaporization due to the small pressure drop through the valve port 24. The effective flow area of the port 24 is greater than the combined flow areas of the orifices 38 so that substantially instantaneously with the opening of the quickly acting valve member 30, the feeding chamber 23 will be filled solid with liquid refrigerant and no vaporization of the liquid refrigerant in the chamber 23 will occur. The size or volumetric capacity of the chamber 23 is sufiiciently large so that during operation of the compressor I there will always be liquid refrigerant overlying the orifices 38 with the result that liquid refrigerant will be fed to the feeding tubes II and therefore the refrigerant will be equally and uniformly distributed to each of the passes or tubes I2 of the evaporator I 3.

The valve member 30 is controlled by the magnet coil 21 which is in turn controlled by a relay switch 39 having its relay coil 40 in the electrical network of a photocell system including the light source II. The light beam indicated by the dash dot line H from the source I1 shines through the transparent suction conduit section I6 and when not refracted by liquid refrigerant, the light beam passes through an aperture 42 in a. shield or box 43 containing a photo-electric cell 44 and impinges upon the cathode 45. Energization of the cell 44 by thelight shining upon the cathode 44 renders the control grid 45 of the electron tube 41 sufllciently positive so that current flow through the tube 41 will occur, thereby energizing the relay coil 40 to close the switch 39 and open the valve member 30. The electrical network including the relay coil 40, tube 41 and cell 44 may be any of the well known systems supplied with alternating current from the usual line voltage transformer 48 and therefore a detailed description of the network is not necessary to a full understanding of this invention. When liquid refrigerant enters the transparent conduit section I6 and refracts the light beam 4I so that it fails to pass through the shield aperture 42, then the electron tube 41 will be deenergized the liquid refrigerant intercepts the 4 and the switch 39 will open so that the valve 30 will move quickly to closed position under the force of gravity and spring 32.

The operation of the refrigeration system of Fig. 1 will be apparent from the foregoing, al though it may be noted that the system is particularly adapted for use in air conditioning or the like where the load on the evaporator I3 will be maintained substantially constant. At the beginning of a cycle of compressor operation the liquid refrigerant line will have receded toward the header I4 from the conduit section I6 so that the valve 30 will be open and refrigerant will be supplied to the feeding chamber 23 and thence to the evaporator tubes I2. As soon as light beam 4| sufiiciently to deenergize the cell 44, then the valve 30 will close as above noted. Intermittent opening and closing of the valve 30 will then continue during the compressor operation so that liquid refrigerant will be maintained in the feeding chamber 23 and the evaporator I3 will be refrigerated throughout its length.

Referring to Fig. 2 the electric distributor 8 is controlled by a differential switch 50 having volatile liquid power elements 5I, 52 with temperature responsive bulb elements 53, 54 respectively. The power elements 5| and 52 operate to close the switch 50 whenever the difference between their respective temperatures exceeds a predetermined amount, the switch closure energizing the distributor coil 21 so that liquid refrigerant is supplied to the feeding chamber 23 and thence to the evaporator I3. The bulb 53 is clamped to one of the evaporator tubes I2 adlacent its inlet end and the bulb element 54 is clamped to the suction line I5 so that irrespective of the temperature range to which the bulb elements 53 and 54 are subjected, they will function to control the switch solely in accordance with the differential between their temperatures and accordingly will maintain the evaporator I3 completely refrigerated during the compressor operating cycle. The operation of the system of Fig. 1 with the control switch 50 will be apparent from the foregoing description.

Having thus described my invention, what is claimed and is desired to be secured by Letters Patent of the United States is:

1. In a refrigerating apparatus a multi-tube evaporator having a suction header, a tubular vertical housing member, a horizontal partition dividing said housing member internally into an upper inlet chamber and a lower liquid feeding chamber, said partition having a valve port, a casing on the upper end of said housing member, an electro-magnetic coil in said casing, a valve member in said inlet chamber and movable to close and to open said port and having an armature cooperable with said coil, a bottom Wall closing the bottom end of said feeding chamber and having a plurality of passageways therethrough leading from said feeding chamber, each of said passageways having a calibrated orifice portion, said port having an effective flow area when said valve member is open which is greater than the combinedfiow areas of said orifice portions thereby to maintain liquid refrigerant in said feeding chamber, said housing member having an inlet passageway to said inlet chamber, refrigerant feeding tubes connecting said bottom wall passageways to the tubes of said evaporator,

and switch means responsive to the extent of refrigeration of said evaporator and controlling said electro-magnetic coil.

2. In a refrigerating apparatus a multi-tube evaporator having a suction header, a tubular vertical housing member, a horizontal partition dividing said housing member internally into an upper inlet chamber and a lower liquid feeding chamber, said partition having a valve port, a casing on the upper end of said housing member, an electro-magnetic coilin said casing, a valve member in said inlet chamber and movable to close and to open said port and having an armature cooperable with said coil, a bottom wall closing the bottom end of said feeding chamber and having a plurality of passageways therethrough leading from said feeding chamber, each of said passageways having a calibrated orifice portion, said port having an effective flow area when said valve member is open which is greater than the combined flow areas of said orifice portions thereby to maintain liquid refrigerantin said feeding chamber. said housing member having an inlet passageway to-said inlet chamber, refrigerant feeding tubes connecting said bottom wall passageways to the tubes of said evaporator, a relay switch controlling said electro-magnetic coil, a suction conduit connected to said header, and photo-electric controlling means responsive to predetermined flow of liquid refrigerant into said suction conduit and controlling said relay switch.

'3. In a refrigerating apparatus, a plurality of refrigerant evaporating members, a common suction line leading from said members, a housing member 'having an inlet chamber with an inlet for admission of liquid refrigerant and having a liquid feeding chamber communicating with said inlet chamber through a valve port, a valve member controlling said port and having open and closed positions, electrically operable means to.

move said valve member quickly from and to said positions, said housing member having a plurality of passageways leading from the bottom of said feeding chamber, each of said passageways having a calibrated orifice portion, said valve port having an effective flow area when said valve member is in said'open position which is greater than the combined flow areas of said orifice portions thereby to maintain liquid refrigerant over said passageways and in said feeding chamber, refrigerant feeding tubes connectlng said passageways to said evaporating members, and means responsive to a refrigerant condition in said suction line and controlling the energization of said electrically operable means.

4. A liquid refrigerant distributing device, comprising a housing member having an inlet chamber with an inlet for admission of liquid refrigerant and having a liquid feeding chamber communicating with said inlet chamber through a. valve port, a valve member controlling said port and having openand closed positions, means to move said valve member quickly from and to said positions, said housing member having a plurality of passageways leading from the bottom of said feeding chamber, each of said passageways having a calibrated orifice portion, said valve port having an effective flow area when said valve member is in said open position which is greater than the combined flow areas of said orifice portions thereby to maintain liquid refrigerant over said passageways and in said feeding chamber.

5. A liquid refrigerant distributing device. comprisin a housing member having an inlet chamber with an inlet for admission of liquid refrigerant and having a liquid feeding chamber communicating with said inlet chamber through a valve port in the top wall of said feeding chamber, a valve member controlling said port and having open and closed positions, electrically operable means to move said valve member quickly from and to said positions, said housing member having a plurality of passageways leading from the bottom of said feeding chamber,,each of said passageways having a calibrated orifice portion, said valve port having an effective flow area when said valve member is in said open position which is greater than the combined flow areas of said orifice portions thereby to maintain liquid refrigerant over said passageways and in said feeding chamber.

6. A liquid refrigerant distributing device, comprising a housing member having an inlet chamber with an inlet for admission of liquid refrigerant and having a liquid feeding chamber communicating with said inlet chamber through a .valve port in the top wall of said feeding cham ber, a solenoid operated valve member on the inlet side of and cooperable with said port and having only full open and full closed positions, said housing member having a plurality of passageways leading from the bottom of said feeding chamber, each of said passageways having a calibrated orifice portion, said valve port having an effective flow area when said valve member is in said open position which is greater than the combined flow areas of said orifice portions thereby to maintain liquid refrigerant over said passageways and in said feeding chamber.

7. A liquid refrigerant distributing device, comprising a housing member having an inlet chamber with an inlet for admission of liquid refrigerant and having a liquid feeding chamber communicating with said inlet chamber through a valve port, a valve member controlling said port and having open and closed positions, means to move said valve member quickly from and to said positions, said feeding chamber having an open lower end, a closure member for said lower end and sealed to said housing member, said closure member having a. plurality of passageways therethrough leading from said feeding chamber, an orifice plate secured to said closure member and having calibrated orifices therethrough registering with said passageways, said valve port having an effective flow area when said valve member is in said open position which is greater than the combined flow areas of said orifice portions thereby to maintain liquid refrigerant over said passageways and in said feeding chamber.

8. A liquid refrigerant distributing device, comprising a housing member having an inlet chambez with an inlet for admission of liquid refriger nt and having a liquid feeding chamber communicating with said inlet chamber through a valve port, a valve member controlling said port and having open and closed positions, means to move said valve member quickly from and to said positions, said feeding chamber having an open -bottom end, a closure member clamped to said housing member and closing the bottom end of said feeding chamber and having a recess in its chamber face, said recess extending beneath the wall of said housing member, a plurality of passageways extending vertically through said closure member and leading from said recess, an orifice plate fitting said recess and having an edge portion underlying said housing member wall and clamped between said housing member and said closure member, said orifice plate having calibrated orifices therethrough registering 7 with said passageways, said valve port having an efiective flow area when said valve member is in said open position which is greater than the combined flow areas of said orifice portions thereby to maintain liquid refrigerant over said passageways and in said feeding chamber.

FRANK'LYN Y. CARTER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Berydoll May 16, 1939 Rustige Mar. 30, 1920 Campbell Feb, 11, 1936 Labberton Feb. 21, 1939 Rickett July 6, 1943 Protzei1er Sept, 8, 1931 Morton Jan. 3, 1939 Shrode J an, 24, 1939 Lawrence Oct. 14, 1919 Young Mar, 10, 1925