US2288067A - Ice cream freezer - Google Patents

Description

June 30, 1942.

A. H. BOILEAU ICE CREAM FREEZER Original Filed Jan. 26, 1939- 2 Sheets-She et'l mvmbx cfirt/La/H Bgieaw BY ATTORNEY.

June 3Q,1i.94l2. A. H. BOILEAU 6 I ICE CREAM FREEZER Original Filed Janf26, 1939 2 Sheets-Sheet 2 Patented June 30, 1942 4 UNITED STATES PATENT, OFFICE Arthur H. Bz faz ifi zifdtf zwa, assignor to Cherry-Burrell Del., a corporation rporation, Wilmington,

Original application January 26, 1939, Serial No.

252,884. Divided and this applicationDecem- .ber 26, 1939, Serial No. 310,892

8 Claims. (01. 62-414) The present invention relates to an attempering apparatus, such as confection freezers, and, is directed more particularly to the construction of the refrigerant evaporator or refrigerant confining passage associated with the freezing or.

attempering chamber and to the refrigerant flow control apparatus associated with the refrigerant evaporator for putting the evaporator quickly into also desirable to be able to accurately control such refrigeration action in a minimum amount of time and with a minimum number of operations. Evaporators adapted or capable of such use are particularly desirable in the manufacturing of ice cream by the batch process. Such outer surface of the processing chamber and the I adjoining surfaces of the evaporator shell and particular desirability is brought about by the normally quick, repeated operations incidental to the emptying of one batch and the re-loading and freezingof the next ba'tchl Such construction and the performance of such evaporators enables the almost instantaneous attainment of maximum efiiciency of'the refrigeration in the freezing operation.

The accompanying drawings illustrate the invention in an ice cream freezer of the batch. type. However, the invention is not to be limited to the specificembodiment described. The

portion of the invention pertaining to the agitator element, as shown in Figure 1, is more particularly referred to, as Well as claimed, in my co-pending application referred to above.

rator, and also utilizing the a'ffixing mans a fins on the outer surface of the processing chamber to facilitate the more eflicient heat transfer to the refrigerant medium. An additional object is to provide an evaporator for 'a processing chamber in which the evaporator is so constructed and arranged as to directly apply the ,volatile refrigerant tothe surface of the processing chamber in intimate con tact therewith and guide the refrigerantin a circuitous path thereabout, whereby, due to the pressure caused by the gas of evaporation, high,

speed is attained-in the motion of the refrigerant, which high speed of the refrigerant causes it to pass in intimate scouring contact over the fins formed thereon .to effect thereby a separation of the liquid from the gaseous refrigerant and the removal of gas bubbles from the surface of the heat transfer elements. Such construction efiects an improvement in the rate of heat transfer from the materialsbeing treated in the processing chamber to the refrigerant medium circulated thereabout.

A still further'object of this invention is to provide means to deliver volatile refrigerant to the evaporator casing about. the processing chamber and to receive it therefrom whereby intermittent,- prompt operation of the refrigeration system at maximum capacity without discharg- The principal object of the present invention is to provide an icecream freezer'evaporator of simple, efiicient and inexpensive designwherein the operator has accurate and immediate control of the freezing process within the freezing chamber, which control is maintainable'by a minimum of operations.

A further object of the invention resides in the method of making the evaporatorassociated ken' away section, showing the evaporator emwith the processing chamberin which the outer evaporator shell is affixed to the outer wall of the processing chamber in a, manner utilizingthe aflixing elements as guide means for the refrigerant being circulated through the evapo-v ing-unused refrigerant to the compression may be secured, as well as to pre-cool the liquid refrigerant before it enters the evaporator by the use of unevaporated refrigerant discharged from the processing chamber evaporator.

Other objects and purposesand other important features of the invention willbe apparent from the following description when read in connection with the accompanying drawings in which:

Figure 1 is a longitudinal sectional view taken vertically through the freezer.

Figure 2 is a sectional view taken vertically through-the automatic thermal refrigerant valve for the freezer.

Figure 3 is an elevational view in partially brobracing the processing cylinder of the ice cream freezer. Referring to the illustrations showing the preferred embodiment of the invention, in which 11- lustrations likejnu'merals are associated with like elements, the invention, which particularly pertains toan ice cream freezer evaporator and the method of constructing the same, is illustrated in connection with an ice cream freezer. The ice cream freezer is supported on a hollow base I resting on adjustable feet I I. A gear housing I2 is provided at the upper rear portion of the base and a cylinder supporting bracket I3 is provided immediately ahead of the gear housing I2, together with a cylinder supporting shelf portion i4 immediately ahead of the bracket I3, above which shelf is mounted the cylinder structure generally indicated by the numeral 15 applied to its envelope. The freezer is driven by motor l6 housed in the hollow base I0 and mounted on any suitable bracket I1. The motor I6 through a series of belts I8 drives the pulley l9 which is keyed to drive shaft journaled in suitable bearings in the gear housing l2. Pinion 2| is carried by and keyed to the drive shaft 20 and drives the.

spur gear 22 carried by a quill shaft 23 journaled in .any suitable sleeve bearing 24 mounted directly above drive shaft 29 with the quill shaft 23 opening outwardly through the front wall of the gear housing l2. Quill shaft 23 is joined at its inner end'to the adjoining free inner end of a second axially aligned shaft-25, which is partially telescoped into quill shaft 23 and there supported in alignment by a suitable rotary thrust bearing 26. The outer end of the shaft 25 is journaled in any suitable bearing generally indicated by the numeral 21. Sprocket wheel 28 fixed to and carried by shaft 23 is driven by sprocket chain 29 which passes around a driving sprocket 39 driven through the intermediacy of the disc clutch generally indicated by the numeral 3i on which it is mounted. Disc clutch 3| is mounted on the drive shaft 20 and actuated by lever 32 pivoted at 33 and hinged at its free end to the control rod 3 f extending outwardly through the front wall of the base I0 toward the position occupied by an operator-of. the freezer.

The inner shaft 35 and quill shaft 36 are the shafts used to drive the inner and outer elements of the reversely rotatingv agitating of the agitator mechanism within the shell 31.

The evaporator C comprises a helical evaporator passage defined on its inner surface by the- I I1 is provided with an interruption or slot H9 approximately equal to the width of the ring I I6 and immediately adjacentthe ends I2l of the ring-like elements H6 along the line of cleavage of the split rings and advancing in a clockwise direction therefrom. ..To complete the helical passage H0, defined on its inner and outer mechanism of the freezer. These shafts are tel-' I escoped at their freeends into the squared sockets of the shafts 25 and 23, respectively, by means of which squared faces the reversely rotating spur gear 22 and sprocket wheel 29 impart the reverse rotation to the shafts36 and 35, respec-v tively, to operate the inner and outer dasher elenients.

The processing cylinder construction comprises an outer envelope I5 and an inner processing shell 31 which serves as a refrigerated wall or cylinder housing the freezing chamber of'the freezer. The shell 31 is surrounded by a re-' frigerant evaporator C in intimate contact therewith and spaced from envelope I6, in which space a satisfactory cover or insulation 33 is provided. Shell 31 is provided at its front end with an annular head 39, and at its opposite end with a centrally apertured head 40. Heads 39 and 40 are aflixed to shell 31 and envelope I! by any suitable means, such, for example, as welding,

and head 49 is rigidly affixed to the cylinder support bracket I3 by a series of bolts. A removable end wall or door 4| including the usual inlet passage 42 and outlet passage 43 is hinged in the conventional manner to the front cylinder head 39. The outlet passage 43 is closed by valve 44,

' and the inlet passage 42 is associated with the usual type of mix reservoir 43 through the conventional type of valve 46, all of which are clear- 1y shown vided with a conical, central, inwardly directed in Figure 1. The 'end wall 4| is pro-' nearthe second to, the last shell H3 slightly passing the- 'surface by the shell 31 and the joined ring-like elements H6, and defined along its edges by the adjacent flange H1, bafile elements I20 are provided intermediate the flanges and intermediate the adjacent slots H9. The baffle elements I20 are inclined to the plane of the elements H6 and are mounted immediately adjacent edge I2I of each of the rings H6, having their inner edge welded tothe periphery of shell 31 and their outer edge welded to and joining the angularly cut ends I2I of the ring H6. .The forward end of eachbafile element I29 is joined to the end of a flange H1 defining the lower edge of the associated slot H9 immediately ahead of the baflle element, and the rear edge of each baflle I20 is joined to theadjacent end ofa flange H1 defining the upper edge of the adjacent, rearwardly positioned slot H9. By so joining the opposite ends of adjacent flanges H1 the helical passage H9 intermediate adjacent portions of the flange I I1 is defined. The helical passage H0 is provided with an inlet port III at its front upper end and discharge port H2 at its lower opposite end. Liquid refrigerant is supplied to inlet port III through conduit H3 affixed to the outer surface of the evaporator C', and communieating with conduit 93 through nipple H4.

Evaporated or gaseous refrigerant is discharged from passage I III to the discharge port H2 joined by nipple H5 to the refrigerant discharge conduit 94.

The foremost or front shell H6 is also pro-v vided with an inwardly turned flange H1 at its front edge H8 as well as its rear edge, both of which-flanges H1 are welded tothe outer periphery of shell 31 to their inner edges to complete the enclosure of passage H0. To form a continuous helical passage utilizing the annular space between the shell-like structures H6 and the shell 31 when assembled as just described.

each flange H1, excepting the front flange of the: front shell and the flange oftherear shell, is providedwith a slot or laypass H9, as just described, joining the annular space on either side of the slotted flange H1. These slots are of approximately the same length as the width of the shells H 1 and are arranged in-staggered relation, progressing uniformly rearwardly and downwardly with the slots of the first shell H6 top of the shell 31, and the slot in the lower portion of the shell 31. To complete the helical passage H0, baffle means I23 are pro-- bearing support 41 which supports the front end vided intermediate adjacent flanges II! at an incline to the axis of the shell 6, joining the lower edges of a slot H9 with the upper edge of the adjacent rearwardly positioned slot- II9 as just described. The baflle means I20 in the foremost and rearmost shells H6 are joined at their extreme ends to the unslotted outermost flanges III of evaporator C, and are inclined similarly to the remaining bafiles I20. Bafiles I20 are welded at their respective ends tothe adjoining flanges Ill, and at their inner and outer edges they are welded to the shells 3! and H6, respectively. v

The baflie I20 in the foremost shell is positioned immediately below the refrigerant inlet port III in such a manner as to cause the liquid entering therethrough to flow in a counterclockwise direction through the annular passage formed by the foremost shell I I6, thence through the slot H9 joining the passage bounded by the two foremost shells, thence in a counter-clockwise direction around the portion of the helical passage .bounded by the second shell IIB due to the positioning of the second baffle I20, and thence similarly through the remaining shells I I6 until the refrigerant reaches the discharge II2 in a gaseous state.

,The agitating, whipping, scraping and unloading mechanism comprising part of the ice cream freezer shown in Figure 1 is set forth in detail and claimed in my co-pending application referred to previously. Generally speaking, the agitator shown in Figure 1 consists of inner and outer rotary elements. A front spider 55, by means of a bushing I2, supports the front end of the agitator mechanism on the shaft 35 which is provided at its front end with a stud bearing 63 to engage a complementary bearing seat in the freezing chamber door 4|.

Similarly, a rear spider co-acts with a drive shaft to support the rear portion of the agitator assembly. The outer agitator element, in addition to being provided with scraping blades, is

also provided with unloading bars 53 carrying the angularly disposed unloading wings 54. The inner agitator element is provided -with two sets of beater blades 66 and 81 alternately arranged on a supporting shaft and at'an angle of ninety degrees one to another. Whipping rods 68 are carried by the beater blades and are, anchored at their rear extremities in a whipping rod support or'spider I0.

In this divisional application some of the figures of the parent application have been appropriated and consequently the identifying numbers 49 to 81 inclusive and 106 to 109 inclusiveshown in the parent case have not been referred to as they pertain primarily to the agitator element which is covered in detail in the parent application.

It is, .of course, obvious that the evaporator 88 through conduit 89, thence through conduit 89' to an automatic liquid refrigerant flow regulating valve 90 to a control valve 9| through conduit 92, and thence through the special evaporator connection 93 from which it passes As a matter of safety, a .poppet valve 96, con 7 ventionally referred to as a safety valve, is joined The automatic thermal liquid flow valve 911, as I illustrated indetail in Figure 2, is in the re-- frigerant supply line and is of the commercial type offered on the market under the trade mark C may be supplied with other types 'of cooling agents to eifect a satisfactory operation of the ,freezing processes within'the shell 31. However,

the illustrations clearly set out. a portion of an ammonia absorption system and the controls therefor.

In'the preferred embodiment of the invention supplypipe 83, from which it passes through a coil 84 of the pre-cooler 85, thence through a conduit 86 to a needle valve BI'provided with a bypass through which bypass the liquid may pass during normal automatic operation to valve offAlco, and the details thereof do not form a part of this .invention. Valve will be described only sufliciently to indicate. that the liquid passing through the valve is regulated by a conical valve 90 seating in aco'nical valve seat in the flow passage I00. The movement of the valve 98 is controlled through valve stem IOI which is fixed to a spring-loaded diaphragm I02 actuated by the pressure exerted upon it by the fluid in tube I04 communicating with the thermal-sensitive bulb I03 mounted in heat exchange relation on the exhaust conduit 94.

' In the event that it is desired to manually operate the evaporator C, the valve 88 ahead of the automatic thermal valve 90 is closed and the needle and bypass valve 81 is adjusted to regulate a flow of liquid refrigerant to the conduit 92 as desired through the conduit I05 connected to one of the discharge ports of the needle and bypass valve 81. The inlet port of valve 81 is associated with the beforementioned bypass, form ing a part thereof, which bypass is not shown but is constructed inaccordance with convenusing the manual controls as set forth. Such manual control, forwhich the liquid refrigerant would be supplied through bypass I05, may also be used when a degree of refrigeration is desired outside of the scope of that permitted by the use of the automatic valve 90.

'It will, of course, be evident that some of the chief advantages of the present invention reside in the evaporator per se and the method of constructing'the evaporator *C and the result 'in'- herent in such construction, as well as the general arrangement and system whereby the refrigerant applied to the processing shell 31 is readily controllable in the desired manner, as

spaced relation one to another, staggered rearwardly and downwardly as shown in Figure 10. The baffles I20 as a group extend rearwardly and downwardly in uniformly spaced staggered relation one to another in a somewhat helical alignment with the foremost b aflies I20 positioned approximately at the top of the forward end of the shell 31. The rearmost baflie- I20 is positionedapproximatelyat the bottom of the rear portion of the shell 31. The front discontinuous or split ring H6 having an inwardly directed flange H1 at both of its edges is next superimposed over the forward end of the shell 31 with the ends I2I of the split ring H6 embracing the front baflle I20. The edges; of the inwardly turned flange I I1 of the front ring H6 are each welded to the periphery-of the shell 31 and the ends I2I of the ring H6 are joined to the outer edge of the baffle I20 and the ends of the bafile I20 are each welded to the adjacent flange H1. The lower end of the rear flange H1 of the front ring H6 is welded to the front edge of the second baffle element I20 positioned immediately adjacent the rear edge of the front ring I I6. The second ring H6 is then superimposed over shell 31 with the ends I2I of the second ring H6 embracing the outer edge of the second baffle I20 and having the front edge I I8 of the second ring H6 abutting against the rear edge of the frontelement H6. The front edge H8 of the second element I I6 is then welded to the rear edge of the first element H6 and the ends I2I of the second element H6 are Welded to the'upper edge of the second element I20. The ends of the flange H1 of the second element H6 which defines the top edge of the slot H9 in the second element H6 is then welded to the rear edge of the second bafiie I20 and the other end of the same flange H1 is welded to the front edge of the third baflle I20. The third and other elements H6 are mounted on shell 31 in like manner with the exception of the last and rearmost element H6 which is not provided with a slot I I9 in its flange I I1. In the instance of the last ring-like element H6 the rear flange H1 is welded to the she1l-31 throughout its entire length which in this instance extends throughout the entire length of element H6 from each of the edges I2I thereof. The unique method of constructing an evaporator for an ice cream freezer, as just described, forms a passage H which is made continuous throughout all of the elements H6 by providing connecting bypasses in the form of slots H9 in the flanges H1 intermediate any two adjacent hoop or shell-like elements H6 so associated with defining baflles I as to direct the refrigerant flowing through the passages H0 in a circuitous helical path in intimate contact with the outer periphery of the freezing shell 31. Due to the welding of the inwardly directed flange II1 to the outer surface of the shell 31, the flanges H1 in actuality constitute heat exchange fins extending-into the evaporator C, thereby greatly increasing'the heat transfer efficiency of the evaporator due to the inherent advantages incidental to the structure of the evaporator, whereby the efficient heat transfer surface has been increased.

In the operation of the freezer, ice cream mix supplied to the reservoir is admitted to the 'freezing or processing chamber defined by the shell 31 through valve 46 and the refrigerant is started or stopped by means of the stop valve 9|, which valve admits the pre-cooled refrigerant from the automatic control valve 90 into the conduits associated with the evaporator C. Any unevaporated or liquid refrigerant which may pass through the evaporator C passes through the conduit 94 into the pre-cooler 85'where it will be evaporated to avoid the passage of any liquid refrigerant into the exhaust line 95 associated with the compressor condenser unit (not shown). This arrangement is well adapted for the efficient and satisfactory operation of batch freezing processes in which frequent starting and stopping of the freezing operation is essential. In the-event manual control of the refrigeration system is desired the automatic thermal control valve 90 is turned off by closing valve 80 immediately ahead of valve 90 and opening the needle valve 81 which is then used to regulate the flow of liquid refrigerant to the evaporator C through the stop valve 9|.

The foregoing detailed description has been given for clearness of understanding only and no unnecessary limitations shall be understood therefrom. Various changes in arrangement of the various elements of the freezer, as shown and described to explain the invention, may be made in accordance with the common knowledge of those skilled in the art and yet come within the scope of the invention as set forth in the appended claims.

The invention is hereby claimed as-follows:

1. An evaporator for refrigeration apparatus comprising a freezing chamber defined by a shell forming the inner Wall of said evaporator, an outer wall structure fabricated of contiguous sheet'metal elements, each having a continuous inwardly extending flange fixed to said shell throughout its entire length, and a continuous substantially helical refrigerant passage formed intermediate said shell and said outer wall, said passage being defined along its sides by adjacent flanges of said sheet metal elements.

2. A heat exchange medium passage for attempering a chamber comprising a shell defining the outer wall of said chamber, a plurality of liquid baflie means sealed to the outer periphery of said shell along their inner edge, a plurality of discontinuous ring-like elements sealed together along their adjacent edges and superimposed over said shell to embrace said baflle means in a sealing contact along their outer edge intermediate the ends of said ring, and uninterrupted inwardly directed flange means carried along a portion of an edge of each of said rings having their respective ends sealed to alternate ends of adjacent baflie means and having their free edge sealed to the outer periphery of said 3. An ice cream freezer comprising, in combination, a freezing chamber defined by ashell forming the inner wall of an evaporator and gas separating means, an outer wall structure fabricated of sheet metal and defining the outer wall of said evaporator, said outer wall structure having a. continuous, inwardly extending, helical flange fixed to said shell throughout its entire length, a continuous substantially helical refrigerant passage intermediate said shell and said outer wall, said passage being defined along its edges by adjacent elements of said helical flange, refrigerant supply and discharge conduits associated with the opposite ends of the passage within said evaporator and gas separating means,

' automatic valve means in said supply conduit for controlling the flow of refrigerant to said evaporator and gas separating means, said automatic valve means being responsive to the temperature of refrigerant in said discharge conduit,

and heat exchange means associated with said refrigerant supply and discharge conduits forcated of sheet metal and defining the outer wall of said evaporator, said outer wall structure having a continuous, inwardly extending, helical flange fixed to said shell throughout its entire length, a continuous substantially helical re- 2,2ss,oe7 I baiile means welded to the outer surface of said frigerant passage intermediate said shell and said outer wall, said passage being defined along its edges by adjacent elements of said helical flange,-

refrigerant supply and discharge conduits associated with the opposite ends of the passage within said evaporator and gas separating means, automatic valve means in said supply conduit for controlling the flow of refrigerant to said evaporator and gas separating means, said automatic valve means being responsiveto the temperature of refrigerant in said discharge conduit, and heat exchange means associated with said refrigerant supply and discharge conduits for evaporating any unevaporated refrigerant discharged from said evaporator and gas separating means.

5. An evaporator and gas separator for an ice cream freezer comprising a freezing cylinder, a plurality of baflies welded to the .outer surface of said cylinder, and-a plurality of fabricated sheet metal elements superimposed over the outer surface of said cylinder in such a manner that each of. said elements embraces one of said baiiie means, said fabricated sheet metal elements being sealed one to another and to said baiiie means to form a segment of a fluid flow passage, said fluid flow passages communicating with each adjacent flow passage in such a manner as to form from. the segmental fluid flow passage a series-connected refrigerant flow passage encircling said freezing cylinder.

6. An evaporator and gas separator for an ice cream freezer comprising a freezing cylinder,

cylinder, and a discontinuous metal ring-like element superimposed over said cylinder to embrace a bafile means intermediate the ends of said ring-like element, said ring-like element having its edges welded to the outer periphery of said cylinder and to the top edge of said embraced bailie means.

7. An articlev of manufacture' comprising a freezing cylinder, a plurality of baiile means welded to the outer surface of said cylinder, a

discontinuous metal ring-like element superim-' posed over said cylinder and embracing one of said baflie means intermediate the ends of said ring-like element, said ring-like element having its edges welded to the outer periphery of said cylinder and to the top edge of said embraced baflie means, and a second ring-like element superimposed over said cylinder and abutting against said first mentioned ring-like element and embracing one of said bafiie means intermediate its ends, said second ring-like element being welded to said first ring-like element along the line of contact therewith and having its free edges welded to said baiiiemeans embraced thereby and to said cylinder.

8. In an ice cream freezer, a cylinder for containing material from which heat is to be extracted, a plurality of outwardly extending fins having their inner edges fixed to the outer periphery of said cylinder in intimate permanent union therewith and arranged in side by side order one with respect to another, a laterally disposed outer portion on each fin overlying the space between two adjacent fins and flxed to the outwardly extending portion of the adjacent fin in intimate permanent union therewith, the outwardly and laterally extending portions of said adjacent fins and the outer periphery of said cylinder, when joined in intimate permanent union one with another, forming a fluid passageway, and fluid passage connections between ad- Jacent fiuid passageways so arranged as to form a hello-like circuitous refrigerant passage encircling said cylinder, whereby the heat exchange between said cylinder and refrigerant flowing within said circuitous passage is improved.

ARTHUR H. BOlLEAU..

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