US2051801A - Refrigerating apparatus - Google Patents

Refrigerating apparatus Download PDF

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US2051801A
US2051801A US728514A US72851434A US2051801A US 2051801 A US2051801 A US 2051801A US 728514 A US728514 A US 728514A US 72851434 A US72851434 A US 72851434A US 2051801 A US2051801 A US 2051801A
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refrigerant
vessel
syphon
float
chamber
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US728514A
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Lawrence A Philipp
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Kelvinator Inc
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Kelvinator Inc
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B41/00Fluid-circulation arrangements
    • F25B41/30Expansion means; Dispositions thereof
    • F25B41/31Expansion valves
    • F25B41/315Expansion valves actuated by floats

Definitions

  • valves of thisnature are very susceptible to many difficulties because of the extremely small apertures and orifices pro-' videdfor metering the,refrigerant.
  • Such very small openings are susceptible to stoppage because of small pieces of dirt, and in time they are also liable to wear because of the wearing action of the fine grit and dirt in the system.
  • stoppage because of the freezing of water moisture, were also subject to frosting back, and were relatively expensive to build and service.
  • Another object of my invention isto provide means in conjunction with anintermittently operated refrigerant compressor unit for intermittently releasing quantities of the condensed refrigerant to the evaporator.
  • liquid level responsive means are connected in series re lation between the refrigerant condenser and the refrigerant evaporator.
  • the first liquid level responsive means connected to the condenser comprises a liquid receiving vessel having a syphon one end of which is opened to the interior of said vessel. The other end of the syphon opens into 'a float chamber.
  • liquid fills the syphon vessel to a apparatus shown in Fig. and minimized predetermined level where it primes the syphon. A predetermined-quantity of liquid then flows from the vessel into the float chamber.
  • the float As soon as the liquid refrigerant in the fl'oat chamber attains a predetermined level, the float is lifted and operates a valve 5 through a leverage mechanism. The opening of the valve releases the refrigerant from the float chamber to the evaporator.
  • the refrigerant regulating valve is either open or shut and the use of expansionvalves and re- 10 stricted orifices in the, system is avoided.
  • Fig. 1 is a diagrammatic view representing a refrigerating system controlled in accordance with 20 my invention.
  • Figs. 2 and 3 are views showing modifications in which the syphon vessel and the float chamber are united in a unitary structure.
  • the 1 comprises acompressor I for compressing the vaporized refrigerant which it draws through a suction line 2 from the refrigerant evaporator 3'.
  • the compressor l is driven by an electric motor 6 which is controlled by a snap action switch I through which it may be connected to the line conductors.
  • the switch I is actuated by an expansiblebellows 8 interconnected through a pipe 9 to a thermo bulb I0 which is mounted adjacent the evaporator 3 or in the space cooled thereby in the usual manner.
  • the switch! is quickly operated by a snap action mechanism l3 'to energize the motor 6 from the line conductors l6 and I! when the temperature adjacent the thermo bulb rises to a predetermined maximum.
  • the refrigerant vapor As the refrigerant vapor is. compressed it passes from the compressor 8 through a condenser 2
  • the vessel 26 encloses a curved pipe 21 of inverted u formation which com- I prises a syphon.
  • the bottom plate 29 of the syphon vessel 26 may be removably secured to the side walls thereof in any suitable'manner as by threadable engagement therewith.
  • comprising cup shaped side which are inverted upon a removable base plate 32, encloses and supports an' automatic float actuated valve.
  • the valve comprises a reciprocatable piston member 33 which may be moved into sealing relation with a valve seat 34- to shut off the flow of liquid from the chamber 26.
  • the valve is actuated by means of a suitable leverage mechanism. As shown, this mechanism may comprise a pair of pivoted arms 35 the free ends of which are connected by a U-shaped bracket 36 to a buoyant float 31.
  • the syphon vessel 26 is connected through the extended leg 28 of the syphon pipe 21 into the sidewall of the float chamber 3
  • a vent pipe II is connected from the upper portion of the float chamber 3
  • the thermostatically controlled switch 1 starts the compressor unit whenever the temperature within the space adjacent the evaporator rises to a predetermined value.
  • the compressor operates the compressed refrigerant passes through the condenser 2] where its heat is dissipated and the condensed refrigerant passes down to the syphon vessel 26.
  • the liquid rises to the predetermined level in the vessel 26 it primes the syphon pipe 21 and liquid starts to flow into the float chamber 3
  • the float After a predetermined passed into the float chamber the float is lifted to actuate the leverage mechanism which in turn opens the valve 33. After a predetermined quantity of liquid has passed from the syphon vessel the open end of the syphon is no longer immersed. The syphon then goes dry and no more liquid will pass from the syphon vessel 26 until it has again been filled.
  • the evaporator thus intermittently receives predetermined quantities of the condensed refrigerant through valve means which has a positively open and a positively closed position thereby avoiding the use of expansion or throttling valves having very small orifices with the attendant disadvantages. In this manner of operation, intermittent cooling and defrosting of the evaporator can be accomplished. In the oprelatively large quantities of refrigerant are dumped into the evaporator these conditions the refrigerant vapor is very dense and the compressor Operates more efliciently.
  • the float valve and the syphon vessel may be combined in a unitary structure as illustrated in Fig. 2.
  • may be extended downwardly to provide a second compartment 62 thereunder, to enclose the valve 33 and its actuating float 31 which is mounted upon an end plate 53 threadably received or otherwise secured in the end of the casforms and applications amount of liquid has disc along the VP curve.
  • a syphon in said the sidewalls of the syphonv is connected to the condenser and the pipe 66 from the lower end of the float valve chamber is connected to the evaporator.
  • the two housings are combined in one and the two interconnecting conduits are eliminated thereby providing a more compact unit which may be more conveniently installed.
  • a combined unitary structure may also be provided by extending the walls of the float valve chamber sufliciently to receive a liquid receiving syphon vessel 62 which is mounted above the float as shown in Fig. 3.
  • verted U shaped syphon pipe 63 may be supported-over or through the upper edge of the liquid receiving syphon vessel 62 in such a manner that its longest branch is suspended in the float chamber and the shorter branch is suspended in the liquid receiving vessel 62 where it terminates adjacent the bottom thereof.
  • the upper pipe fltting is connected to the condenser and the lower to the evaporator as in the previous modifications.
  • a refrigerant evaporator,refrigerant compressor-condenser means, means for actuating said compressor-condenser intermittently in accordance with temperature conditions vmeans operatively interconnecting said compressor-condenser and said evaporator including syphon means operable during the operation of the compressor for periodically passing predetermined quantities of liquid refrigerant 2.
  • a refrigerant condenser In combination a refrigerant condenser, a refrigerant evaporator, means operatively interconnecting said condenser and evaporator including a syphon vessel and a'float valve chamber connected in'series relation for intermittently predetermined quantities of liquid to said evaporator.
  • a refrigerating system comprising a refrigerant evaporator, a refrigerant compressor, a refrigerant condenser.
  • means operatively interconnecting said oompresso condenser and evaporator including a refrigerant receiving syphon vessel and a refrigerant receiving float chamvessel for controlling the the float chamber, and a in said chamber for interquantities of refrigerant .5.
  • the combination with a refrigerating system comprising a high side portion, a low side and a float type valve for. regulating the flow of refrigerant from the high side portionto the low side portion. of means providing a dumping action of said float valve.
  • said means comprising a refrigerant receiving vessel disflow of refrigerant to float actuated valve mittently into said evaporator.
  • the combination in a refrigerating system comprising a high side portion and slow side portion of means for regulating the flow of refrigerant from the high side portion to the low side portion comprising a vessel for receiving refrigerant from the high side portion. and syphon means for intermittently discharfl na quantities of refrigerant from said vessel.
  • the combination in a refrigerating system comprising a high side portion and a low side portion of means for regulating the flow of refrigerant from the high side portion to the low side portion comprising a vessel for receiving refrigerant from the high side portion, syphon means for intermittently discharging quantities of refrigerant from said vessel, a chamber for receiving the refrigerant discharged from the vessel and a float actuated valve in said chamber for intermittently discharging the stored refrigerant to the low side of the system.
  • a refrigerating system comprising a high side portion and a low side portion of means for regulating the flow of refrigerant from the high side portion to the low side portion comprising a vessel for receiving refrigerant from the high side portion, syphon means for intermittently discharging quantities of refrigerant from said vessel, a downwardly extended portion of said vessel comprising a chamber for receiving the refrigerant discharged from the vessel, a vent conduit for discharging gas from said chamber into said vessel and a float actuated valve in said chamber for intermittently discharging the stored refrigerant to the low side of the system.
  • a refrigerating system comprising a high side portion and a low side portion of means for regulating the flow ,of refrigerant from the high side portion to-the low side portion comprising a vessel for receiving refrigerant from the high side portion, syphon means for intermittently discharging quantities frigerant from the high side portion to the low of refrigerant from said vessel, a chamber for receiving the refrigerant discharged from the vessel and in which said vessel is disposed, and a floatactuated valve in said chamber for discharge ing e stored refrigerant to the low side of the 5 new 10.
  • a refrigerating system comprising a high side portion and a low side portion of means for regulating the flow of reside portion comprising a vessel for receiving refrigerant from the high side portion.
  • syphon means for intermittently discharging quantities v of refrigerantfrom said vessel, a separately disposed chamber for receiving the refrigerant discharged from said vessel, a vent conduit connected from the upper portion of said chamber to the upper portion of said vessel and a float actuated valve in said chamber for intermittently discharging stored quantities of refrigerant to the low side of the system.
  • Refrigerant flow controlling means for regulating the flow of refrigerant from the high side to the low side of a refrigerating system 1.20mprising a unitary housing, a syphon base plate in said housing for separating the enclosure into a syphon vessel and a float valve chamber, inlet means for admiting refrigerant to the vessel,

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Devices That Are Associated With Refrigeration Equipment (AREA)

Description

Aug. 18, 1936.. A. PHILIPP I ,REFRIGERATING APPARATUS Filed June 1, 1934 2 Sheets-Sheet 1 INVENTOR. Law/951m: z]. Pllu/gv BY I I ATTORNEY.
Aug. 1851936.. A, PHI mp 2,051,801-
' REFR'IGERATING APPARATUS Filed June 1, 1934 2 Sheets-Sheet 2 i, i Lmrgzn'cz HIM/PP WM MAZJQ ATTORNEY.
Patented Aug. 18, 1936 UNITED STATES PATENT orrica imrnrerna-rme Arram'rus Lawrence A. Philipp, Detroit, Mich, assignor Kelvinator Corporation, Detroit, Mich., a cor:-
poration of Michigan Application in... 1, 1934, Serial No. 728,514 12 Claims. (01. 62-115) maintain a predetermined relation between the.
high pressure liquid and the low pressure liquid or gaseous refrigerant. For this purpose it has been common to use the well known expansion or float valves. However, valves of thisnature are very susceptible to many difficulties because of the extremely small apertures and orifices pro-' videdfor metering the,refrigerant. Such very small openings are susceptible to stoppage because of small pieces of dirt, and in time they are also liable to wear because of the wearing action of the fine grit and dirt in the system. In addition to being subjected to stoppage by dirt and wear by grit, such systems were all subject to stoppage because of the freezing of water moisture, were also subject to frosting back, and were relatively expensive to build and service.
It is accordingly an-object of my invention to provide a refrigerating system of improved efliciency, simplified construction, service requirements.
It is a further object of my. invention to provide a refrigerating system which avoids the use of all extremely small holes and orifices for metering the refrigerant and the attendant difliculties of line frosting and frequent servicing.
It is also an object of my invention to provide a liquid. refrigerant responsive meanssin a refrigerating system for controlling the flow of condensed refrigerant to the evaporator in conjunction with liquid refrigerant responsive means for intermittently releasing predetermined quantities of the condensed refrigerant.
Another object of my invention isto provide means in conjunction with anintermittently operated refrigerant compressor unit for intermittently releasing quantities of the condensed refrigerant to the evaporator. I
In accordance with my invention two liquid level responsive means are connected in series re lation between the refrigerant condenser and the refrigerant evaporator. The first liquid level responsive means connected to the condenser comprises a liquid receiving vessel having a syphon one end of which is opened to the interior of said vessel. The other end of the syphon opens into 'a float chamber. In. operation liquid fills the syphon vessel to a apparatus shown in Fig. and minimized predetermined level where it primes the syphon. A predetermined-quantity of liquid then flows from the vessel into the float chamber. As soon as the liquid refrigerant in the fl'oat chamber attains a predetermined level, the float is lifted and operates a valve 5 through a leverage mechanism. The opening of the valve releases the refrigerant from the float chamber to the evaporator. In this arrangement,
the refrigerant regulating valve is either open or shut and the use of expansionvalves and re- 10 stricted orifices in the, system is avoided.
The invention itself, however both as to its organization and its method-of'operation, to-' gether with additional objects and advantages thereof, will best be understood from the follow- 15 mg description of specific embodiments, when read in conjunction with the accompanying drawings in which:
Fig. 1 is a diagrammatic view representing a refrigerating system controlled in accordance with 20 my invention; and
Figs. 2 and 3 are views showing modifications in which the syphon vessel and the float chamber are united in a unitary structure.
Referring more specifically to the drawings, the 1 comprises acompressor I for compressing the vaporized refrigerant which it draws through a suction line 2 from the refrigerant evaporator 3'. The compressor l is driven by an electric motor 6 which is controlled by a snap action switch I through which it may be connected to the line conductors. The switch I is actuated by an expansiblebellows 8 interconnected through a pipe 9 to a thermo bulb I0 which is mounted adjacent the evaporator 3 or in the space cooled thereby in the usual manner. The switch! is quickly operated by a snap action mechanism l3 'to energize the motor 6 from the line conductors l6 and I! when the temperature adjacent the thermo bulb rises to a predetermined maximum.
As the refrigerant vapor is. compressed it passes from the compressor 8 through a condenser 2| where its latent heat of vaporization is dissipated into space in the well known manner. -From the condenser 2| the liquefied refrigerant passes through a suitable conduit 25 into a liquid receiving vessel 26. The vessel 26 encloses a curved pipe 21 of inverted u formation which com- I prises a syphon.
- walls 36,
ported in open spaced relation adjacent the bottom 29 of the vessel. The bottom plate 29 of the syphon vessel 26 may be removably secured to the side walls thereof in any suitable'manner as by threadable engagement therewith.
A float chamber 3| comprising cup shaped side which are inverted upon a removable base plate 32, encloses and supports an' automatic float actuated valve. The valve comprises a reciprocatable piston member 33 which may be moved into sealing relation with a valve seat 34- to shut off the flow of liquid from the chamber 26. The valve is actuated by means of a suitable leverage mechanism. As shown, this mechanism may comprise a pair of pivoted arms 35 the free ends of which are connected by a U-shaped bracket 36 to a buoyant float 31.
The syphon vessel 26 is connected through the extended leg 28 of the syphon pipe 21 into the sidewall of the float chamber 3|. A vent pipe II is connected from the upper portion of the float chamber 3| to the upper end of the syphon vessel 26 in order to vent the float chamber and permit the liquid to enter from the syphon vessel. From the float chamber 3| the liquid refrigerant passes through a conduit 44 to the header 45 of the evaporator 3.
In operation the thermostatically controlled switch 1 starts the compressor unit whenever the temperature within the space adjacent the evaporator rises to a predetermined value. As the compressor operates the compressed refrigerant passes through the condenser 2] where its heat is dissipated and the condensed refrigerant passes down to the syphon vessel 26. When the liquid rises to the predetermined level in the vessel 26 it primes the syphon pipe 21 and liquid starts to flow into the float chamber 3|.
After a predetermined passed into the float chamber the float is lifted to actuate the leverage mechanism which in turn opens the valve 33. After a predetermined quantity of liquid has passed from the syphon vessel the open end of the syphon is no longer immersed. The syphon then goes dry and no more liquid will pass from the syphon vessel 26 until it has again been filled. The evaporator thus intermittently receives predetermined quantities of the condensed refrigerant through valve means which has a positively open and a positively closed position thereby avoiding the use of expansion or throttling valves having very small orifices with the attendant disadvantages. In this manner of operation, intermittent cooling and defrosting of the evaporator can be accomplished. In the oprelatively large quantities of refrigerant are dumped into the evaporator these conditions the refrigerant vapor is very dense and the compressor Operates more efliciently.
In order to provide a more convenient and compact assemblage of elements the float valve and the syphon vessel may be combined in a unitary structure as illustrated in Fig. 2.. In this embodiment of my invention chamber 6| may be extended downwardly to provide a second compartment 62 thereunder, to enclose the valve 33 and its actuating float 31 which is mounted upon an end plate 53 threadably received or otherwise secured in the end of the casforms and applications amount of liquid has disc along the VP curve. Under ber, a syphon in said the sidewalls of the syphonv is connected to the condenser and the pipe 66 from the lower end of the float valve chamber is connected to the evaporator. In this manner the two housings are combined in one and the two interconnecting conduits are eliminated thereby providing a more compact unit which may be more conveniently installed.
' A combined unitary structure may also be provided by extending the walls of the float valve chamber sufliciently to receive a liquid receiving syphon vessel 62 which is mounted above the float as shown in Fig. 3. verted U shaped syphon pipe 63 may be supported-over or through the upper edge of the liquid receiving syphon vessel 62 in such a manner that its longest branch is suspended in the float chamber and the shorter branch is suspended in the liquid receiving vessel 62 where it terminates adjacent the bottom thereof. In this embodiment the upper pipe fltting is connected to the condenser and the lower to the evaporator as in the previous modifications.
It will be seen that I have provided a refrigerating system of improved efflciency, which is 01' simplified construction requiring a minimum of service attention.
In this embodiment the in- While it is necessary for the purposes of illustration to describe the several disclosed forms of my invention in detail, it will be apparent that theinvention is not so limited and that other thereof are embraced within the scope of the appended claims.
I claim as my inventions v 1. In combination a refrigerant evaporator,refrigerant compressor-condenser means, means for actuating said compressor-condenser intermittently in accordance with temperature conditions, vmeans operatively interconnecting said compressor-condenser and said evaporator including syphon means operable during the operation of the compressor for periodically passing predetermined quantities of liquid refrigerant 2. In combination a refrigerant condenser, a refrigerant evaporator, means operatively interconnecting said condenser and evaporator including a liquid receiving vessel, and syphon means responsive to the accumulation of liquid refrigerant in said vessel for dumping quantities of liquid into the evaporate 3. In combination a refrigerant condenser, a refrigerant evaporator, means operatively interconnecting said condenser and evaporator including a syphon vessel and a'float valve chamber connected in'series relation for intermittently predetermined quantities of liquid to said evaporator.
4. A refrigerating system comprising a refrigerant evaporator, a refrigerant compressor, a refrigerant condenser. means operatively interconnecting said oompresso condenser and evaporator including a refrigerant receiving syphon vessel and a refrigerant receiving float chamvessel for controlling the the float chamber, and a in said chamber for interquantities of refrigerant .5. The combination with a refrigerating system comprising a high side portion, a low side and a float type valve for. regulating the flow of refrigerant from the high side portionto the low side portion. of means providing a dumping action of said float valve. said means comprising a refrigerant receiving vessel disflow of refrigerant to float actuated valve mittently into said evaporator.
posed between said high side portion and said float valve and a syphon therein for intermittently dischargin quantities of refrigerant from said vessel to the float valve.
6. The combination in a refrigerating system comprising a high side portion and slow side portion of means for regulating the flow of refrigerant from the high side portion to the low side portion comprising a vessel for receiving refrigerant from the high side portion. and syphon means for intermittently discharfl na quantities of refrigerant from said vessel.
'I. The combination in a refrigerating system comprising a high side portion and a low side portion of means for regulating the flow of refrigerant from the high side portion to the low side portion comprising a vessel for receiving refrigerant from the high side portion, syphon means for intermittently discharging quantities of refrigerant from said vessel, a chamber for receiving the refrigerant discharged from the vessel and a float actuated valve in said chamber for intermittently discharging the stored refrigerant to the low side of the system.
8. Thecombination in a refrigerating system comprising a high side portion and a low side portion of means for regulating the flow of refrigerant from the high side portion to the low side portion comprising a vessel for receiving refrigerant from the high side portion, syphon means for intermittently discharging quantities of refrigerant from said vessel, a downwardly extended portion of said vessel comprising a chamber for receiving the refrigerant discharged from the vessel, a vent conduit for discharging gas from said chamber into said vessel and a float actuated valve in said chamber for intermittently discharging the stored refrigerant to the low side of the system.
The combination in a refrigerating system comprising a high side portion and a low side portion of means for regulating the flow ,of refrigerant from the high side portion to-the low side portion comprising a vessel for receiving refrigerant from the high side portion, syphon means for intermittently discharging quantities frigerant from the high side portion to the low of refrigerant from said vessel, a chamber for receiving the refrigerant discharged from the vessel and in which said vessel is disposed, and a floatactuated valve in said chamber for discharge ing e stored refrigerant to the low side of the 5 new 10. The combination in a refrigerating system comprising a high side portion and a low side portion of means for regulating the flow of reside portion comprising a vessel for receiving refrigerant from the high side portion. syphon means for intermittently discharging quantities v of refrigerantfrom said vessel, a separately disposed chamber for receiving the refrigerant discharged from said vessel, a vent conduit connected from the upper portion of said chamber to the upper portion of said vessel and a float actuated valve in said chamber for intermittently discharging stored quantities of refrigerant to the low side of the system.
11. Refrigerant flow controlling means for regulating the flow of refrigerant from the high side t'othe low side of a refrigerating system comprising a float chamber. a float actuated valve in the lower portion of said chamber, a bucket mounted in said chamber above said valve, inlet means for discharging refrigerant into said bucket. and a syphon mounted in.a side wall of said bucket for intermittently discharging refrigerant so therefrom.
l2. Refrigerant flow controlling means for regulating the flow of refrigerant from the high side to the low side of a refrigerating system 1.20mprising a unitary housing, a syphon base plate in said housing for separating the enclosure into a syphon vessel and a float valve chamber, inlet means for admiting refrigerant to the vessel,
, a syphon extending above and through said base mwasncn it PM.
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