US1731546A - Refrigeration - Google Patents

Description

'J. C. SMITH REFRIGERATION Oct. 15, @1929.

Original Filed April 7. 1 922 4 Sheets-Sheet m lllllll l A llllllllll n\w m V A 7701mm .J. C; SMITH 7 1,731,546

REFRIGERATI ON Oct. 15', 1929.

Original Filed April 7. 1922 4 Sheets-Sheet 2 INVENTQR ATTORNEY Oct. 15, 1929. J c, SMITH 1,731,546

REFRIGERATION Original Filed April '7. 1922 4 Sheets-Sheet 3 INVENTOR A TT'OIe/VE y Oct. 15, 1929. c, sMlTH 1,731,546

REFRIGERATION Original Filed April 7. 1922 4 sheets sheet 4 1A" VEN TOR 4 Patented 15,

' UNITED {STATES {PATENT OFFICE.

JESSE c. surrx, or new You, my.

REFRIGERATION amas filed April 7, 1922, Serial mi. 550,291. Renewed August so, 1929.

This invention relates to refrigerating machines or apparatus. Refrigerating apparatus of the absorption type obtains its coolin effect by the rapid expansion of condense ammonia gas or anh drous ammonia. As the expansion takes p ace heat is absorbed by the gas thereby coolmg the surrounding media from which the heat is taken.

The usual cycle of operation of devices ofthis character includes heating a solution of ammonia and water toexpel the ammonia 'as, cooling the gas under pressure to conenseit to a liquid form, rapidly expanding the anhydrous liquid under reduced pressure and absorbing in water or weak liquor the gas formed by the raipiid expansion.

Most of the di culties experienced 1h refrigerating apparatus of the type described an or' in refri eration by the ammonia process have been ue tothe use of mechanical moving parts such as pum s and to leaking joints and stuffing boxes. oreover, such refrigerating apparatus has required the use of an electricmotor, steam'pump or other driving means to operate-the moving parts and to maintain the circulation through the system.

One of the objects of this invention is to,

simplify the process 'of refrigeration, to utilize a minimum number ofparts and to eliminate the use of mechanical moving parts and driving motors. Y V

Another object of the invention is to provide a refrigerating apparatus in which the circulation of the fluid is obtained through the pressure of the gas and is due to the differences in pressure at different partsof the ap aratus;

nother object of the invention tolpro so vide a refrigerating device having itsparts so constructed and arrangedas toinsure a' continuous and uninterrupted service during the operation of 'the device. Another object of the i vention is to provide in refrigerating apparatus. of the class described, means for insuring an adequate or measured supply of liquidin'the various arts v of the apparatus where the liquid is uti ized.

. I Another object of the inventionis to pro-- '50. vide a refrigerating device-of the absorption plate thereby freeing the ammonia.

ammonia gas is conducted toa condenser and;

' 'Another object of the invention is to pro- 5 viderefrigerating apparatus so constructed and arranged that it is set in operation by the application of heat. and the power used for maintaining the operation and the circulation' of the fluid and carrying through of {he cycle is derived from the application of ieat. l

Further objects of the invention will appear from the followin specification taken in connection with the rawings which form- 05 a art of this-application and'in which ig. 1 is a sectional elevation illustrating refrigerating apparatus constructed in accordance with'the invention. Fig. 2 is a transverse sectional elevation taken substantially on' line 2-2 of Fig. 1.

Fi 3is a sectional elevation taken sub- 7 stantially on line 3-3 of Fig. 1.

Fi 4 is a sectional elevation taken substant ally on line 44 of Fig. 1.

Fig. 5 is a erespective view of a refrigerator having t e refrigerating device mounted thereon. V i a Fig. 6' is a a diagrammatic view -illus trating the process of refrigeration and apso paratus employed.

Fig. 7 is an elevational view showing a measuring or constant supply device for the pump chambers The invention maybe briefly described as a process and apparatus for carrying out. the various steps of the ammonia absorption. refrigeration process in the usual manner but maintaining the circulation of. the fluid through the various arts and the continuous cooperation of the eye e by means of pressure derived from the generation or formation, ofv the ammonia gas. This is accom lished in thedevice' about to be describedy dropping or flowin strong ammonia'solution in water on aTfit is there condensed under pressure to a liquid .andthe-liquid ispassedthrough an-expansion valve and from the valve through an expansion coil and isgasified therein by heat absorbed from the surrounding media. From the expansion .coil the ammonia gas passes to an absorber and is absorbed by the weak liquor and from the absorber the strong liquor is returned to theboiler or place 'ofapplication of the heat. The means for maintaining the circulation in the system and for returning the liquor to the boiler includes members which may be termed pumps and these. devices are operated entirely by the pressures developed in the process and are not driven by anyoutside source of power.

1&5

' vice, disposed therein and a porous member 12 such as a piece of quartz filter or equiva-- lent material-is mounted in the casing above the hot plate and between the incoming li'quor and plate.

' he quartz filter is composed of fine grains of quartz tightly compressed and then slightly vitrified. The small grains being uneven in shape, do not fit closely and thus interstices or air spaces are formed in the body.- The total area of all these small openings is equivalent to several squarefeet and the cooling, surface is confined in. a small space and is very compact.-

The liquor filters down through the porous member 12 and the 1 supply is so'regulated that-it drops from the porous member onto the hot plate in asteady stream or one drop at a time,'a s desired. The'va or immediately rises from the hot plate an passes through the porous member and as it'passes upward liy it'meets'the .cool liquor which is passing wnwardly through the member 12. This condenses any moisture or water in the vapor which'is'passing upwardly and separates it from the ammonia gas which passes through the members-12 and into the outlet pipe 13. a The sup ly ofincoming liquor is controlled by aball oatlslidablymounted on as'tem that operates a ball or valve. 16 which is.-

.15 on the upperend of which is a stop 15 (i ted-to seat on an inlet port 17.,

e pipe 13 conducts the ammonia gas at A apressure of about 125po'unds to a condenser "c011 B which.'-is immersed in a jacket of Water 120; The gas is cooled down by the water and.

is condensed .to'diquid ammonia'or an anhydrousliq'uid. The-anhydrous liquid passes I from the-.condenser through a'rpipe 21 and through a thermostatic" expansion valve22 of the usual c'onstruction'to. an expansion coil A 0. As the gas passesthrough the condenser coil B and condenses to a liquid the pres-l sure is maintained but in the expansion coil 0 the pressure is about 30 pounds. In this .coil the anhydrous liquid expands rapidly.

into a gas and in so doing absorbs heat from the surrounding media thereby giving the desired cooling effect. At 30 pounds pressure ammonia evaporates at the temperature of about 30v to 35' degrees Fahrenheit. If a' lower temperature is desired a lower pressure must be maintained in the expansion coil. Atmospheric pressure would give minus 12 degrees Fahrenheit.

From the expansion coil C the ammonia gas is conducted through a pipe 23 to an absorber D containing a weak solution oi ammonia. or a weak liquor under substantial;

ly' 20 to 30 pounds pressure. The ammonia gas passing from the pipe 23 intothe ab sorber is entirely absorbed by the liquor thereby concentrating the solution and forming a strong liquor. lhe weak liquor is supplied to the absorber B through a'pipe 30 and the supply is controlled by a ball valve 3lwhich in turn is controlled by a float. 32. I

The pipe 30 receives the liquor from a cooling coil E and this coil is connected by pipe 33 to the bottom of the generator or boiler A as shown at 34. The passage of the liquor from the cooling coil E to'the pipe is controlled by a needle valve 35 or an opening or orifice of a predetermined size.- Cir- I I .culation through the pipe 30 iseii'ected. by

the diflerence in pressures between the generator'and the absorber.

The means whereby the operation of the cycle just described is maintained and whereby the liquor is returned to the generator or boiler will now be described.

.' This means comprises one, or preferably, a

pair of cylinders F; which may be termed umps and are also submerged in thewater acket 20. The gas is conducted to each of these cylinders through pipes 40 communieating with the pipe 13. The inlet port 41 of each cylinder F'is controlled-by a ball or equivalent valve 42 which in turn is con trolled b a lever 43 actuatedby a float 44.

Weak 'quor is also conducted to the cylinders F by a pipe 45 which communicates with the pipej30 and also with inletazpipes 46. t The supply ofweak liquor passing to the cylinders is controlled in the embodiment of the invention shown in .Fig'. 6 by needle valves 47.

Strong liquor islconducted to the. bottom of each of the pumps Firomthe? bottom of the absorber "D. This liquor is conducted 7 through a pipe .50 from the" bottom of the Q absorber to an inlet pipe 51foonnected to the bottom of one I of the eylinders F',i-the admission to thispipe bemgcontrolledbya check valve-52 shownas a ball valve; The

. pipe 50 is also connected to an inlet pipe 53 connected to the bottom of the other cylinder and this inlet is controlled by a ball check valve 54.

The'strong liquor is conducted from the cylinders or pumps F to the inlet port 17 of the generator or boiler A in the follow ing manner. A by-pass 60 communicates with the inlet pipe 51 of the cylinder F and a by-pass '61 communicates in a corresponding manner with the intake 53 of the other cylinder. Each of these by-passes leads to a pipe 62'which inturn communicates with a pipe 63 connected at its other'end to the intake port 17 of the boiler or generator A5 In the by-passes, however, or between the by-passes of the pipe62 are ball check valves 64 and 64A which control the passage of the liquor to the pipe 62.

- The rate of flow of the liquor through the pipe 63 and to the heater may be controlled by the valve 35 in pipe since the rate of flow from the generator A through pipes 33' and 30 to the pumps will control the operation of the pumps F and thus'the discharge therefrom.

Before describing the operation of the apparatus I will describe the structure shown in Fig. 7 which has for its object to maintain an adequate supply or a measured quantity. of weak liquor in the pump cylinders F. This device consists of a reservoir or constant supply chamber G which .is interposed between the pipe 41 and each of the pump cylinders F. A nozzle has one end 71 disposed adjacent. the bottom of the chamber G and has its other end 72 extending into and discharging into the cylinder F. A check valve 73 is interposed between the chamber G and the supply pipe 30.

This apparatusis used to inject a'measured quantity of weak liquor into pum measured quantity being just su cient to F, the

completely absorb all of the ammonia gas remaining-in the cylinder F after the gas has been cooled.

The structure shown in Fig. 7 operates as follows. Startingwith F. filled with an ammonia gas at apressure of 125 pounds and valve 42 just closed off by'ball float 44, the

gas in F: commences to cool by contact with the water 'cooled walls of This icooling causes shrinkage in volume and naturally a decrease in pressure. .In order that the, cycle of operation may be'hastened the apparatus as shown in Fig. 7 now begins to. unction. With ,valve 64A closed by pressure of gas in A, the pipe 72bei'ng the only connection with A, any difl'erence in pressure between A and F will tend to cause a flow of weak li uor from A through 46pa-st the ball'valve 73, mto

the reservoir G and thence to F. The greater the pressure diflerence the faster will be the flow. Ball valve 73'isadjusted so that it moves very freely and at a certainlvelocity' weak liquor in G is used to force the weak liquor through the spray nozzle 72, thus com- .p'leting the absorption of the gas.

The operation of the apparatus will now be outlined. When the heat is applied one of the pump cylinders F will be' filled with strong liquor and the other one I will assume is empty. As the heat increases the pressure in A also increases due to the vaporizing of the liquor around the heating device 11 and naturally this tends to equalize and become the same in all parts of the system. Thus a a flow of liquor is set up in the pipe 33, causing the level of liquor in A to be lowered. In order that this level maybe maintained the ball float 14 opens the valve 17, thus permitting liquid toflow from 63 to the top of the 'filter 12 As the liquor passes down through absorber D. The ball check valve 24 or other suitable valve, is interposed between the absorber D and the pipe 23 to prevent the liquor in the absorber from passing into this ipe, as for instance. when the device is shut own and the gas flow into the absorber is stopped. This absorber contains weak liquor under a pressure of substantially 20 to 30 pounds which will absorb the gas, and the strong liquor will pass from the absorber through the pipe 50. During this operation the gas will also pass from the pipe 13 through one of thepipes 40 to one of the cylinders F. In Fig.6 gas is shown as passing to the left hand cylinder, sincethis cylinder is filled with liquor to a suflicient extent to permit ball float 44 to open theball valve 41. When ball valve 41 is opened the pressure in F is im mediately equalized with that in the genera tor- A and pump F being located above the generator A, gravity creates enough pressure upon ball valve 64A to raise it from its seat, and the liquor thus flows through the pipes 62453 to-the intake port 17 of the generator A. When the liquor is being emptied from one of the cylinders F as the left hand cylinder, the liquor is passing into the other cylinder from the absorber D and 111 Fig. 6' the liquor is passing into the right hand cylinder'. This passage of the liquor into the cyl-. inder F from the absorber takes place because of the difference in pressure between the pres sure in the absorber D and the pressure in the as re ards the parts as that shown in Fig. 6

cylinder F. The pressurein the absorber D is maintained at about 30 ounds by a regulating valve 22 whereas 1n the cylinder F gaseous ammonia above the liquor is being deabsorption of this ammonia gas-'byffth'e fine spray of weak liquor admitted through the pipe 46. The admission of the weak liquor is controlled bythe difl'erence in pressures be-' tween the'pressure in the cylinder F and'the pressure in the feed pipe 45. This condensation of the ammonia gas will cause the pressure within the cylinder to fall to zero or below and since the pressure in the absorber is substantially pounds the strong liquor will pass from the bottom of the absorber through the pipe5O and connecting pipe 51 or 53 'to-the cylinder Ff "When the liquor has risen in the 'cylindersufiiciently to o n the valve llthe ammonia gas is again a mltted under pressure and the liquor is thereafter emptied out and conducted to the generator A by gravity. It will thus be seen that the the generator A.

The embodiment of the apparatus shown 1n Figs. 1-5 inclusive, is substantmlly the same and i'fiers' therefrom only in that the coils B and E in Figs. 1-5 surround the three cylinders D, F and'F. Since the parts correspond in both of these showings corresponding reference characters are used in Figs.'15 and in Fi .6. p %n Fig; 5 the device is shown mounted 1n ,osition on an ice box and the pipes extendlng through the bottom of the device conduct water to and from the water jacket. The hot plate is also shown 'as connectedto an elec tric switch plug.- The'starting and stoppingof the o eration of'the apparatus may be controlled y the manual openin of the electric circuit .to the hot plate, or if esired, the operation'may be automatically controlled by athermostat.

From the foregoing specification it Wlll be seen that a simple, practical and eifective a paratus has been designed and that the eye e of operation is maintained solely through the ferent strong difference inplessure of the fluid in the difquor will be taken into -one of the pump cylinders" because the ressure-within the cyhnder islower than t at-within the absorber and at the same time the llqurd Wlll be fed from theother cylinder; by gravity. to

the generator.

Although one specific embodiment of-the invention has been particular-1 shown and I describedflt willbe understoo -that-the*invention 'is-capable of modification. and that:

1parts of the apparatus. Thus the t e liquid ammonia, anabsorber for ..-'up the gaseous-ammonia, and means for recondenser, an expansion coil receiving the condensed liquid from the condenser, an absorber receiving the gas from'the expansion coil, a pump chamber connected to the ab-' sorber, means for feeding generator gas to said chamber, condensing the gas to lower the chamber pressure below the absorber pressure thereby causin the liquor to pass from the absorber to the c amber, valve mechanism in the pump chamber for controlling the gas admission thereto, said mechanism being controlled by the liquid level in the chamber, and

a conduit connecting the "pump chamber to the generator.

2. Apparatus' of the cla'ss ilescribed com- 4 rom aqua ammonia, a condenserfor liquefy mg the as, expanslon means for gaslfymg to f pumps 01' cylinders F operate alternately lfulsmg a genera r or fieemg'ammoma gas and maintain a continuous flow of liquid to the liqui ammonia,an absorber for taking up the gaseous ammonia, and cooling means for recelvmg and condenslng ammonia gas from pressure, said last named means beingoperable by the reduced pressure to withdraw theliquor fromthe absor r and return the liquor to the generator.

3. Apparatus of the class described comprising agenerator' for freeing ammonia gas from aqua ammonia, a condenser connectedto the generator for liquefying the gas, expansion means connected to the condenser for gasifying' the liquidammonia, an absorber connected to the expansion means for takingthe generator thereby creating a reduced 9. liquor-return conduit for conducting theliquor from the chamber to the generator,

i A pparatus of the class described comppismg a generator for freeing ammonia gas om aqua ammonia, a condenser for liqueing the gas, expansion means for ga'si ng ceiving andcond'ensingammonia ga's' 'frcm the generator th'ereb said a sorber, said last named means being creating a reduced 'pressure lower. than t e pressure in the absorber a connection between said means and located above and connected to the generator,

w *sorbermto sai 'means,,.willi iow-b gravitychanges in the'cons'ti'uc'tion and ,1n, thF.;arto the e liquor} from the absorber and returning the liquor by gravity to the enerator.

5. Apparatu 0 the class described comprising a generator for freeing ammonia as from aqua ammonia, a condenser for lique ying the gas, expansion means for gasifzing the liquid ammonia, an absorber for ta ing up the gaseous ammonia, means for receiving and condensing ammonia gas from the generator thereby creating 'a reduced pressure, said last named means withdrawing the liquor by reason of the reduced pressure rom the absorber and'being located above and connected to the generator whereby liquor can flow by gravity tothe generator and means for controlling the supply of gas received by the last named condenslng means.

6.. Apparatus of the class descrlbed comprising a generator for freeing ammonia gas from aqua ammonia, a condenser for liquefying the gas, expansion means for gasifiyging the liquid ammonia, an absorber for ta ing up the gaseous ammonia, means for receiving and condensing ammonia gas from the generator thereby creating pressure lower than the pressure in the absorber, saidlast named means due to its reduced pressure op- 'withdrawing the liquor from t crating to withdraw the liquor from the absorber and being located above and connected mechanism, andpumping mechanism connected to the absorber and to the generator for withdrawing the liquor from the absorbing' mechanism and returningthe liquor'by gravity to the generator comprising a cylin er, means for conducting gas thereto means for condensing gas-in said cylinder an means for feeding a measured supply of liquor from the generator to the cylinder.

8. Refri erating apparatus comprising a generator or generatin ammonia gas, condensing, expansion and absorbing mechanism, connections between said generator and condenser,- condenser and expansion mechanism, expansion mechanism and absorbing mechanism andumping mechanismconnected to theabsor er and to the enerator for i he absorbing mechanism and returning the liquor by gravity to the generator comprising a cylinder, means for conducting gas thereto, means for condenSingLgas in said cylinder and pressure I feeding a measured supply of liquor from '5.

controlled means including a reservoir for the generatorto the cylinder.

9. Apparatus of the class described com prising a heat actuated generator for freeing ammonia gas from aqua ammonia, a condenser connected to the generator for li 'uefying the gas, expansion means connecte to the condenser for gasifying' the liquid ammonia, an absorber connected to the expansion means for taking up the gaseous ammonia and means disposed above the level of an connected to the generator (for receiving and condensing ammonia gas from the generator thereby creating a pressure below the pressure in the absorber, said last named means due to the reduced pressure'withdrawing the liquor from the absorber and returning the liquor by gravity; to the generator.

10. Refrigerating apparatus comprising means for generating ammonia gas, means for liquefying the gas, an expansioncoil for gasi fying the liquid, an absorber for absorbing the gas, means utilizing gas formedvby the gen-' erating means to produce a'diiference in pressure in different parts of the system, said last named means being connected to the absorber and the generator for receiving and condensing free gas from the generator and being controlled by the variations in pressure and the amountof liquid therein for withdrawing the liquor from the absorber and returning the liquor from the absorber to the generator and thereby completing the cycle of operation, said pressure controlled means being constructed and arranged to operate alternately to withdraw liquor from the-absorber and return the liquor to the generator.

11. Apparatus of the class described, com prising a generator, a condenser, an expander, and an absorber, and means for maintaining the circulation of fluid and the cycle of operation through said apparatus, comprising pumping and condensing mechanism connected to said generator and absorber, said pumping mechanism operated entirely by the uid in the system and depending for its operation on variations in pressure in different arts of the'apparatus, and means for feedmg a measured quantity of liquor from said v generator to said pumplng mechanism.

12. In a refrigerating apparatus of am monia absorption type having a generator, a condenser, an expander, and an absorber, means for maintaining the circulationof fluid and the cycle of operation, comprising pumping and condensing mechanism connected to said generator and absorber, said'mechanism being operated entirely by the fluid in the sgstem, and depending for its operation on t' e variations in' pressure in different parts of the apparatus, and by the amount of liquid in the pum ing mechanism, and pressure control means or feeding a measured quantity of liquid from said generator to said pumping mechanism. 7

13. A refrigerating device comprising a generator havmg means for applying heat to ammonia liquorto free the ammonia; a condenser connected to the generator, anexpansion coil connected to the condenser, an absorber receiving the ,gas from the expansion co1l,-a pump, connections between said pump and said absorber and between. the pump and the generator, said pump receiving and con- 7 densingfree gas from the generator and V operating to returnliquor from the absorber to-said generator, said pump being controlled by the generated gas and operated by the dif+ 'ferences in pressure in the pump and absorber and the amount of liquid in the limp for returning the liquor from the absor 'er to the generator.

- 14. A- refrigerating device comprising a I 1 generator having means for applying heat to a sorber recelvmg the gas from the expansion .-coil, and a pair of alternately operable pumps ammonia liquor to free the ammoma, a con'-- denser connected to the generator, an expan- S1011 0011 connected to the condenser, an abconnected to the absorber and to the generator said pumps receiving and condensing free gas from the enerator and operatingalternat'ely to return iquor from the absorber to the genorator, said pumps being controlled by the generated gas and operated-by the difierences in pressure in'the absorber and pumps and by the amount of liquid in the pum s for feedmg a constant and uninterrupte supply of liquor from the absorber to the generator, said pumps being connected to the absorber and to the generator:

In witness-whereof, I haye hereunto set m hand. this 4th day of April, 1922.

JESSE 0. SMITH. I

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