US1823725A - Refrigerating apparatus - Google Patents

Description

Sept 15, 1931- `s. c. cARNEY l 1,823,725

BEFRIGERATI NG APPARATUS Sept. 15, 1931. s. c. CARNI-:Y

REFRIGERATING APPARATUS Filed Dec. '7. 1925 l L. IIIIIHIIII 2 Sheets-Sheet 2 rafeniecl sept. 1.5,` 1931 UNITED STATES PATENT OFFICE SAMUEL l(Il. CARNEY, OF TULSA, OKLAHOMA, ASSIGNOR TO SHELL PETROLEUM CORPO- RATION, A CORPORATION F VIRGINIA REFRIGERATING APPARATUS Application led December 7, 1925. Serial No. 73,851.

This invention relates to improvements in refrigerating apparatus and consists in the novel construction hereinafter' disclosed.

An object ofthe present invention is to provide an apparatus whereby a refrigerant is kept in constant Contact, largely in liquid form, with the inner surface of a rotating drum, said drum being mounted within a chamber in which the pressure may be re.

duced below -atmospheric and to the outer periphery of which a supply of liquid to be frozen is conducted together with means for removing the liquidv frozen on the periphery of the drum, whereby itmay be packed into cakes for commercial purposes.

Generally stated, the invention consists of the novel construction, arrangement and combination of parts hereinafter described and theparticular advantageous features of the structure will be readily recognized from the detailed disclosure thereof,taken in connectidn with the accompanying drawings in i which Fig/1 is a vertical section throughy the apparatus;

Fig. 2 is across section; and

Fig. 3 is a detail viewin vertical section :of the mold for compacting and removing in cake form the frozen liquid producedby the apparatus.

I-Ieretofore, in practice, in the manufac ture of ice commercially there has been employed two general systems, namely, the can system and the plate. system. In both of these, the heat from the liquid being frozen must be transmitted at a relatively low temcomes covered with athick coating of the .frozen liquid, after which the heat is required to pass from the liquid to be frozen through a considerable thickness of the frozen mass, thus greatly reducing the effectivenessof the system as a whole.

Furthermore in the existing systems, the metallic surfaceof the pipe coil or the chamber in which the refrigerating liquid is being evaporated is, to a considerable extent, in contact with the vapor of the refrigerating liquid rather than with the liquid itself. Especially is Vthis true in a long pipe coil, because the vapor of the liquid first evaporated must pass through the remaining length of the coil leading to the compressor or absorber. This results in a low coefficient of heat transmission, because a considerable part o f the coil surface, namely, that part which is in contact only with the vapor on one side and with the brine solution or wap ter on the other side, has an extremely low rate of heat transfer. VvFurthermore the brine solution or water in contact with' the evaporating coils or chamber causes corrosion of.

the metal of the'refrigerant container, thereby further reducing the rate of heat transfer. The apparatus of the present invention 'overcomes the difficulties inherent in the present systems by freezing'theliquids by means of heat transfer through a relatively thin metallic surface of high heat conductivity and removing the frozen bodies in a relatively small mass, thereby obtaining a high rate of heat transfer anda highefliciency from the refrigerant. f

In the embodiment of the invention shown in the drawings, the foregoing results are accomplished by an apparatus comprising a `housing which includes four segmental sections 1, 2, 3 and 4 respectively, havin matching flanges 5 which are bolted together to form a chamber having substantially the` cross sectional area illustrated (Fig. L2). The housing is supported by legs 6 for conveniently mounting it for operation. The

ends of the housing are closed by end plates 7 and 8 which are bolted directly to flanges 9 formed at the ends of the segments, form.

ling the body of the housing.- The entire 'opposite' ends.

housing is preferably exteriorly insulated by insulating material 10 covering the exposed surfaces thereof.

The castings, forming the housing are joined together so as to form tightseals permitting a partial vacuum to be maintained therein. While the maintenance of a vacuum in the housing is not essential in all cases, it is generally preferable however forthe purpose of removing air or other dissolved gases from the liquids being fro zen. Furthermore, the vacuum acts as an insulating acket preventing undue heat transfer from the exterior of the housing, and thereby -maintaining the lowered temperature within the housing during the freezing operation.

The housing is therefore provided with a top opening 11 into which a' pipe from a vacuum pump may be connected for the purpose of exhausting to the vvrequired degree the` air from the housing and thereby to main- The 'housing is also preferably equipped with sight openings 12 conveniently arranged so that the operation of the device may be observed.

v.These sight openings are closed by transparent sight glasses 13, it being understood that it ispreferable to construct the sight openings so that there will b'e-heat insulation sufficient to avoid the rise of temperature above the desired internal temperature in the housing of approximately thirty-two vdegrees-when ice is manufactured by the apparatus. If the apparatus is usedfor freez- -ing other liquids, necessarily a corresponding internal temperature for freezing such liquid will be maintained.

VA revolvingdrum is mounted within the housing,` said drum comprising a cylindrical wall 14preferably made of a relatively thin metal having a high heat conductivity. The endsof the drum are closed by 'end 'plates 15 which extend beyond the end of and are connected with the member 14 at The walls -15 are insulated by insulating material 16'. The drum is supported for rotation in the housing by hollow shafts. 17 and 18, said shafts leing directly connected to the respective end` plates 15 at the center thereof. .Said shafts 17 and 18 communicate directly with the interior of the drum. They extend` through the end plates 7 "and 8,r stuffing boxes 19 being provided to seal the openings through which said shafts extend. The shaft 17 is journaled in a bearing 20 supported by a bracket 21, said shaft carrying a pulley 22 by means of which the shaft and therefore the drumv may be rotated from any suitable source of power.l

Thel outer end of the shaft 17 is connected into a` chamber 23, the opening through which the conneetionnwith'the chamber 23. is made is sealed by a stutling box 24. The' chamber 23 is supported bya bracket 25 in parallel alinement with the bracket 21 and has an outlet opening 26 into whichv a pipe zle 31, the opening Aof which is slightly below the scraping knife presently to be described.

A series of troughs are arranged around the interior Vwall of the drum, said troughs being composed of inwardly curved walls 32 connected -at their outer end directly With the wall 14 ,and running longitudinally therewith. The Walls 32 have upturned flanges 33 at theirinner ends, said flanges being slightly spaced apart, thus forming a plurality of troughs with longitudinal openn ings 4in the center tlereof running parallel with the axis of the drum. A series of pipes 34 extend `from one trough to another, the connected troughs beingl approximately sixty'degrees apart. By reference to Fig. 2 of the drawings, it will be notedthat the pipes V34 connect alternate ones of `the troughs-which is a suitable arrangement for the number shown in the drawings.

From the description of the refrigerant supply pipe and the arrangement of the troughs with their cross `connecting it will be understood that the original refrigerant supply discharged from the nozzle 31 is supplied to the troughs successively as they pass a point in their rotation slightly below the position of the scraping knife above referred to. Intercommunication between the troughs is foratingfthe Walls 32 along a line of their juncture with the wall surfaces 14 and in- Pipes,

provi/ded for by perf dicated on the drawings by the numeral 35; l

poured into the troughs on the descending` part of the revolution and there is also poured into the descending troughs through the' cross connecting pipes 34 refrigerant which has not leaked out through the perforatlons 35 on the ascending part of the is picked upby the troughs as they successively pass the lowest point in their revolution for distribution to the ascending part of the drum surface by leakage throu h perforations 35 and for transferthroug pipes 34- from the troughs completing the ascending part of the revolution to those beginning the descent.

t Extending longitudinally of the housing ,are two supply pipes 36 and 37, the supply pipe 36 being arranged near the top of the housing and in a plane approximately passing vertically through the axis of the drum 14. The pipe 36 is blanked against one end of the drum vat 38 and extendsoutwardly through a stuffing box 39 at the opposite end, it being understood that the pipe is externally connected with the source of supply of the liquid to be frozen which preferably is supplied to the pipe 36 in a precooled condition. The pipe 36 is perforated -throughout the length thereof that extends `wit-hin the housing and should bel preferably made vadjustable in a rotary direction so that the incoming liquid may be sprayed against the surface of the drum 14 so that it will `flow in both directions over the drum surface. 'Y

The liquid flowing in the direction of rotation of the druin (Fig. 2) serves to bathe the scraping knife edge, and the frozen mass that is scraped fromthe periphery-of the drum by the lznife. Part of the liquid {iowing in the reverse direction of rotation of the drum will `be frozen but a sufficient 4amount should be supplied in order to pro- Vide anv excess to bathe 0E the air bubbles from the portion that is frozen. Any excess liquid flowing in 'either direction accumulates inthe bottom of the housing. The pipe 37 extends longitudinally of the drum 14, it being understood that the arrangement of the inner end of tclie pipe is the same as that described in connection with the pipe 36 and that the pipe 37 also extends outwardly throu h the end plate through a stuiling box iot shown). In other words, the arrangement of the pipe 37 and its mounting is identical with the mounting for the pipe 36, the pipe 37 how- Y ever being positioned just below the scraping knife.

lhe liquid from the pipe 37 is discharged against the drum in the direction of its rotation and the liquid should be applied with sucient 'force to cause. a considerable velocity relative to the surface of the drum, spraying a relatively thin film of liquid against the drum periphery which readili'y freezes due tothe fact that the wall 14` has a very high heat conductivity and the heat from the liquid is rapidly withdrawn by the action of the refrigerant in the drum. The excess liquid 'accumulates in the bottom of the housing and where a liquid such as raw water is used, it is preferable to continuously withdraw the water from the bottom of the housing to prevent concentration of impurities.` The excess liquid is withdrawn through any suitable form of discharge pipe (not shown) which ma-y be controlled by an automatic level lcontrol 40 and the level of the water may or may not be in contact with the lower periphery of the drum. In any event it should not rise to any considerable extent above the lower segment of the drum.

The accumulated excess of the liquid in the bottom ofthe housing will be maintained at a temperature closely approximating the freezing point of the liquid. The temperature may be regulated by controlling the amount of excess supplied through the supply pipes. Tlie excess accumulation of liquid in the housing serves to regulate the temperature in addition to its function in eliminating the air bubbles during the freezing operation. The liquid withdrawn from the housing by suitable means may be used for reintroduction into the apparatus through the supply pipes. l

The accumulated congealed layer of the liquid that is formed upon the periphery of the drum is scraped oif and removed there,-

from by a scraping knife 41 set at a tangent,-

to the periphery of the drum and extending outwardly tlierefroniin the direction of its rotation. The scraping knife extends the full length of the drum and is carried by a rod 42 4that extends outwardly through a stuffing box 43 in the wall of the housing and is adjustable by a hand wheel 44 so as to regulate the contact of the edge of the `knife with the periphery ofthe drum.

lAs the frozen liquidjf is scraped from the drum by the scraping knife 41, it is deiiected into a rectangular mold comprising a bottom wally 45 and side walls 46 and 47, said walls extending longitudinally of the housing within the segment 3 and outwardly for some distance beyond one end of the housing as clearly illustrated in Fig. 3. 'I lie side wall' 46 has an outwardly extending wall substantially in the plane tangential to the periphery of the drum, the outer edgeof which'is near the outer edge of the knife blade and serves to catchand deflect the separatedfrozen particles into the mold.

The :mold is formed with. a cover in two sections, the section 48 which covers the an open end. The portion of the cover within the housing comprises a sliding plate 49 that -is arranged to slide outwardly into a closed -housing 50. vThe entire mold, in-

, reciprocated to open andrlose within the housing of the apparatus. lThe `follower head 51 is operated by a' piston construction including a piston rod 52 that extends througha st'uiing box 53 -in the end wall 'of the housing being connected directly to the follower head 51 at its inner en d. The piston rod extends through a stuliing box 54 in the end of a pistoncylinder 55 mounted extcriorly of the housing. ofthe apparatus. A piston'v 56 is mounted in thepiston cylinder and is arrangedto-reciprocate in the piston to 'move the follower head under force forwardly inthemold cavity and to return the follower .head to the position .shown in Fig. 3 after it has served to compressvthe frozen particles accumulated in the mold. f TheI discharge end of the mold is fitted with asimlarfclose-fitting follower head 57 which is' operated -in the same manner and controlled to move in a direction opposite to the follower head 51 so that by the opposite movement of ythe follower heads '51 and 57, the separated particles or frozen .bod-ies will be compressed, after which the follower head 57 may b e withdrawn from` the discharge end of the mold and lby moving the follower head 51 forward,- the compacted' frozen body in the formof a cake may be moved out of Ythe mold. It is preferable that some degree of heat'should be applied to the exterior'portion of the mold to prethe apparatus.

vent the cake from adhering to the side walls and to facilitate the removal thereof.

. The movable section 49 of the cover is adapted to be reciprocated b means of a rod 58. thatV extends outwar 1y through a stuiing box 5 9 in the end of'thehousing of This rod 58 extends into a. plston cylinder 60 through a stuling box 61, said vrodcarrying at'its end a piston 62 Iwhich pis'ton is double-actingfor moving cover section 49 intov 'a4 position to cover tlclllals WlthOllt depal'tlllg flOm the- Splllt' the the nmold and to a position exterior of the housmg of the apparatus to uncover the v mold. L

It will be understood that the particles or frozen'bodies scraped from the vdrum are accumulated in the interior section 'of the mold when the cover section 49 is withdrawn from the top thereof, The cover section is. then moved to cover themold and the follower heads .are operated as above described the lmold is reset for receiving the accumulation by withdrawing the cover section 49,'-

that part of the frozenlliquid that h as accumulated upon the upperface of the cover section will fall into the mold. The operation of forming the cakes may berepeated as a continuous operation.

vIt will bel noted that the mold is separated from the housing by a baliie wall 63 but that there is a port 64'in the baffle wall so thata. portion of the mold will be submerged in `the excess liquid in the bottom of the housing, serving to maintain the walls of the lmold-at a temperature under vwhich the separated ,particles or frozen bodies may be readily compacted and sufoiently high to preventA the adherence of the frozen cake to the walls of the mold.

While I have described in some detail the construction vof the -mold as a convenient way of forming cakes of the frozen liquid,

the specific construction of the I nold is not part of the invention and is only one way of removing the frozen bodies from the apparatus, The mold may bev dispensed with' and the frozen bodies scraped from the drum maybe discharged directly into the excess liquid in the bottom of the housing and re- 'moved therefromby afcontinuous conveyor fitted to the housing, said. conveyor being of the form and type described and disclosed in my copending application Serial No.-

Itis contemplated -that the supply of refrigerant may be `conveniently controlled automatically by a thermostat device, the

control elementof which may placed* in` the vapor discharge conduit and thatif desired'the liquid supply may be also automatically controlled by suitable thermostat devices, the control elements of which may be subjected to the influence ofthe internal temperature of the housing of the apparatus.

It is contemplated that be supplied with any suitable llquid refrigerant, it beilg .pref hydrocarbon refrigerant be utilized.

I 'am aware that the construction of the apparatus may be-modied in numerous par It' is alsocontemplavted that. the arrangement- Jof internal cross connected troughs of the drum `may/be dispensed with and that the liquid refrigerant mayl bed to the interior of the drum and by varyin the speed of rotationthereof by centrifuga the apparatus may erred, however, that a,

irectly supplied f action, the liquid may be kept in contact with the drum surfaces.

It will be understood that the speed of rotation of the drum may be regulated to control the refrigerating action of the apparatus. l

What I claim and desire to secure by Letters Patent is:

1. In a refrigerating apparatus, the combination of a hermetically sealed housing, a hollow drum adapted to be rotated in the housing, means for admitting a liquid' refrigerant to the interior of said drum, means for maintaining a relatively small amount of liquid refrigerant against a relatively large area of the interior Wall of the drum, means for admitting a liquid to be frozen to the exterior of said drum, means for removing the frozen liquid from the exterior of the drum, and means for compacting and removing the frozen liquid in cake form from said housing.

2. In a refrigerating apparatus, the com bination with a housing of a rotary drum mounted therein, means for admitting liquid refrigerant to the interior of said drum, internal troughs supported by the Wall of said drum and adapted to deflect the liquid refrigerant .against the inner periphery of the drum, and mea-ns for admitting liquid to the exterior of said drum.

3. In a refrigerating apparatus, the combination with a housing of a rotary drum mounted therein, internal troughs supported by the Wall of said drum, means for admitting liquid refrigerant to the interior. of said drum, ,said liquid being distributed against the inner pcripheryof the drum by said troughs, and means for admitting liquid to the exterior of said drum, said troughs being arranged for intereommunication.

4. In a refrigerating apparatus, a sealed heat insulated housing, a hollow drum arranged to rotate Within the housing, an axial supply pipe adapt-ed to admit a liquid r'efrigerant to the interior of said drum, an axial pipe at the opposite end of said drum adapted to withdraw the expanded vapors from the drum, a series of internal intercommunicating troughs a-rranged to distrlbute the liquid Within the drum against the inner periphery thereof, a liquid supply plpe arranged above the drum and having a series of discharge nozzles for discharging liquid against said drum, and .an adjustable knife adapted to remove the layer of ice formed on the drum.

5. In a 'refrigerating apparatus, an hermetically sealed chamber, a rotary drum Within said chamber, means for admitting a refrigerant to the interior of said drum, a spray device for spraying liquid on the exterior of said drum, a partition in said drum constituting a trap for the liquidv in the. bottom of the chamber, a scraping device ar? ranged to remove the liquid congealed on said drum, an adjusting device operable exteriorly of the housing for adjusting said scraping device, and means located within the housing for confining and compacting the congealed liquid scraped from the drum.

6. In a refrigerating apparatus. an hermetically sealed chamber, a rotary drum Within said chamber, means for admitting a refrigerant to the interior of said drum, a spray device for spraying liquid on the exterior ofsaid drum, a partition in said drum constituting a trap for the liquid in the bottom of the chamber, a scraping device arranged to remove the liquid congealed on said drum, and means located Within the housing for confining and compacting the congealed liquid scraped from the drum.

7. In a refrigerating apparatus, an hermetically sealed chamber, a rotary drum Within said chamber, means for adm'itting a refrigerant to the interior of said drum, a spray device for spraying'liquid on the exterior of said drum, a partition in said drum constituting a trap for the liquid inthe bottom of t-he chamber, a scraping device arranged to remove the liquid. congealed on said drum, and a mold located Within the housing near the bottom thereof for receiving and compacting the frozen liquid scraped from the drum. f

8. In a refrigerating apparatus, an hermetically sealed chamber, a rotary drum within said chamber, means for admitting a refrigerant to the interior of said drum, a spray device for spraying liquid on the exterior of said drum, a partition in said drum constituting a trap for the liquid in the bottom of the chamber, a scraping device arranged to remove the liquid congealed on said drum, a mold located Within the housing .near the bottom thereof for receiving and compacting the frozen liquid scraped from the drum, and means lfor controlling the liquid level in the bottom of said drum.

- SAMUEL C. CARNEY.

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