USRE20987E

USRE20987E - Ice cream manufacturing apparatus

Info

Publication number: USRE20987E
Authority: US
Publication date: 1939-01-24

Description

Jan. 24, 1939. A. c. ROUTH ICE CREAM MANUFACTURING APPARATUS Original Filed Dec. 10, 1955 ATTORNEY.

.INVENTOR. ALMOND C Roar/r Reissued Jan. 24, 1939 v Re. 20,987

Almond 0. Routh, Sandusky, om Original No. 2,067,683, dated January 12, 1937,

Serial No. 53,782, December 10, 1935. Application-for reissue May 7, 1937, Serial No. 141,357

21 Claims,

This invention relates to ice cream manufac-' turing methods and apparatus of the class in which liquid or plastic ice cream is continuously pumped or otherwise forced through a freezer and conduit means.

Ice cream during the manufacture thereof into saleable-form is sometimes pumpedor otherwise forced, either in liquid mix condition .or in plastic mix condition, through a conduit system, and con-. currently in a suitable freezing part of the system subjected to low temperature to chill it to.

form-sustaining hardness and is then ejected from the machine into cans or other containers for final hardening, or is extruded from a nozzle in the form' of a continuous form-sustaining worm.

While the ice cream, whether in liquid or plastic mix form is'being pumped through the conduit system in apparatus of this class; air is usually mixed therewith to give the desiredpalatability and consistency to theflnished product. If, however, the' ice cream flows too rapidly through that part of the system, subjecting it to low temperature to harden'it, it will not hardensumciently therein, and furthermore the air will not .be prop erly incorporated therein. Conversely, if the ice cream flows the slowly, it may solidify in the refrigerating portion of the conduit system and block the same, stopping the flow altogether;- and if it continues to flow but at too low a. rate, the air supplied thereto may become-excessive. Thus,

. in systems of this class heretofore proposed, regu-' lating apparatus must be provided to control the speed of the pump to thereby control the flow rate 1 through the system. 7 V

Again, it is often desirable to install ice cream making apparatus in a plant alreadyequipped with a refrigerating system and apparatus and to utilize the same as means. for-freezing the ice cream; and it has heretofore been neces'sary in such cases to' regulate the rateof freezing by means of additional refrigerator regulating ap- .paratu prevent the freezing from taking place too slowly or too rapidly for a given rate ofiiow of ice cream.

Again, in. some cases, when .the ice cream'is extruded in a worm, the worm flowing from the nozzle may not be a solid, well formed wormbut. may have unfilled cavities therein and 'may 'be generally'loosely packed, and this defective condition of the extrudedworm willvary with the rate of fiowandi rate of air admission above re- I g v Figl'fi is a fragmentary'elevational view taken ferredto gm i Among the objects of my invention, therefore,

compactness e b dying my invention; 1

(Cl. 62114) i are to provide in 'an-appar'atus of the class referred to: f v Improved means for controlling the rate of-fiow of the liquid mix orplastlc ice cream being forced through the freezer and the condi'iit'mea'ns;

Improved means for controlling the rate of air '5 admission to the ice cream or mix; I Improved means for controlling the density or of the icecream in the extruded worm; Improved means whereby the rate of mix flow, rate of air-admission, and the compactness of I frozen pr uct may each be adjustably changed or control ed in coordination with each'other;

An improved method and means for continu- 5 ously producing from a liquid mix, ice cream in a compact-form-sustaining worm-of controlled predetermined hardness'and" with a. predetermined controlled proportion oroverrun" of air incorporated therein; j Another object is to'provide, in an ice cream freezing method and means of the class in which ice cream mix is pumped through. the system by a constant speed pump and frozen by a preg I determined. constant freezing temperature, improved means for controlling and regulating the I consistencyof the frozen ice cream;

Other objects are: To provide. improved means whereby with "a single constantspee'd'motor, ice cream may be "produced of predetermined'uniform consistency i even under conditions of variation cf freezing. temperature and ice cream formula; To provide'improvedmeans adapting a given "apparatus'tda great range ofoutpu'tin. gallons j.

per minute; and to agreat 'range of mixfreezing temperature. i

' v i Other objects will he apparentto those skilled in the art to which my invention appertains;

'descriptiontalren in; connection with the accom panying: drawing, in which; i

Fig. 1 is a side elevational view of an apparatus My invention'is'fullydisclosed in the following 9 L 1i Fig. 2 a'fragm ntaryplan view tal gen fron'r the plarieI-jof Fig.1; v

v Jig. 3 is"-a fragmentary-elevational view'v taken from the plane 3-4 -of. Fig.' '1'; v Fig. 4 'is' a viewillustrating in 'longitudinalsec 5 tion and. to an enlarged scale apart of Fig. 1; l

Fig. 5 is a view illustrating in longitudinal sec; I I

tion and tolan enlarged scale a part of .Fig. 1; j

from the plane 6-6 of Fig. 1; and

' certain control means illustrated in Fig. 1.

Referring to the drawing, Ihave shown at I a reservoir or tank containing liquid ice cream mix which may be supplied thereto through a pipe IA from suitable mixing apparatus (not shown). The'reservoir I communicates at a lower portion thereof with a conduit 4 controlled by a valve 2 and branching into conduit portions 5' and I. The conduit portion 5 opens into an auxiliary reservoir 6 and is'controlled by a valve 3.

The conduit portion 1 connects with a pmr of branches 9 and III, the branch 9 having an air inlet valve II associated therewith to be described, the outer end I2 of the conduit portion 9 being closed, and the conduit portion III being the intake conduit of a pump I3 discharging into a pump discharge conduit portion I4 communicatingwith one end of a freezer I5 the other end of which is connected to a freezer discharge conduit portion I6 through a control valve II. The

conduit portion It as shown in solid line may discharge into a can or other'receptacle to contain the ice cream for further hardening and commercial distribution, or as shown in dotted lines, may terminate in a horizontal nozzle I6A fromwhich the ice cream may be extruded in the form of a worm and by various fabricating apparatus hardened and converted into saleable pieces.

The pump I3may be of any suitable or known construction but I prefer to employ apump of the positive displacement type. One form of such pump is illustrated in the drawing in cross-section in Fig. 4 and is of the double impeller type having a pair of involute or like intermeshed impellers -26 supported on rotatable shafts 2I-2I rotated by means of an electric or other motor 22 and enclosed in a pump housing 23 (see Figs. 1 and 4) Such impeller pumps are well known and need not be further described herein; and as is well known, such pumps-create a positive suction or partial vacuum on the intake side thereof, for example, in the conduit portion I0, and create a positive pressure on the discharge side, for example in the conduit portion I4. The motor- 22 preferably drives the pump at a constant speed, this being one of the advantages of my invention,

and the control apparatus for controlling the speed of the motor, and in some cases auxiliary pumps and motors, as required in some prior systems, are unnecessary in the apparatus describedhere as will hereinafter appear.

The freezer I6, while it may be. variously constructed, comprises, in the form illustrated, an

inner sheet metal cylindrical wall 24 through which the mix beingfrozen flows, surrounded by,

V a cylindrical sheet metal wall 26 spaced therefrom, thus providing a chamber 26 for" the circulation of brine or other refrigerant around the cylinder 24 to chill the same to freezing temperature. Surrounding the two main walls 24 I25 thus providing an air-containing space I26 between the walls 25 and I24 and an and 25 are two othercylindrical walls I24; and:

insulating vacuum chamber or space I21 between I theftwoouterwalls I24 and I26. The

all clamped between end heads I26 and cylindrical wall being pressed around the outside or pressed within the inside, as thecase may'l'be,

'cfiannulartapered beads I36 and III as shown for the head 12!, the other head having similar beads not shown. The chambers are by' this means all sealed at their ends.

A passageway I32. is provided communicating with the chamber I21 and externally with a pipe I33 by which, through the agency of a vacuum pump I34, vacuum may be produced in the cham- A passageway I35 in the head In leads from requirements, but by the other apparatus supplied by the same refrigerating plant. As will be apparent hereinafter, my invention has particular advantages in such cases. I

In general, of course, the temperature at which the freezer I5 is maintained by the refrigeration referred to must be a temperature sufflcientlylow to freeze the ice cream mix flowing therethrough into plastic ice cream in the chamber or cylinder 24, and preferably to render it of form-sustaining hardness so that it may, if desired, be extruded from the nozzle lid in a continuous form-sustaining worm of the cross-sectional shape of the nozzle.

The ice cream mix, as willnow be apparent, is caused to flow from the pump I3 through the conduit portion I4 and chamber within the cylinder 24', conduit portion I6, valve I1 and out through the conduit portion I6. The heads I26 and I26 are provided with passageways I36-I36, therefore being in the form of spiders having central portions in which, as shown for the head I26, sleeve bearings I31 may be provided.

While in the chamber 24, the ice cream may be continuously agitated by an agitating means comprising a rotatable shaft 32 rotating'in the bearing sleeves I3I--I3I, the shaft terminating at the head I38 as shown in the drawing and at the opposite end extending out through the head and through, and out of the conduit portion l4. That end of the shaft may be sealed bya gland 32 on a suitable boss through which the shaft extends. Beyond the gland 33, the shaft carries a bevel gear 31 with which is meshed a corresponding bevel ,gear 36 mounted on a generally ver- '15 freezer, may be dictated, not by the freezer andits from tending to freeze thereon and to agitate it and mix it with the body of the ice cream moving throug'hthe chamber. By this means, which corresponds inform and function to the well known batchtype ice cream freezer, the ice cream passing through the chamber may be uniformly manner. extending outwardly through the conduit wall mass, it is known in the art as over-run.

may be of any suitable construction. In the form illustrated, Figs. 1 and 5, being of the spigot type comprising a tapering cone-shaped valve element 43 having therethrough a relatively thin slot-like passageway," which, upon rotation of the valve element 43, adjustably, will variably restrict the iiow through the conduit portion 1 in a'well known The valve element 43 may have a stem through a gland I38 and has a worm gear 45 thereon. A worm 46 meshed with the worm gear has a handle 41 thereon to turn the worm to ad- Just the valve.

Thus, for given amounts of rotary movement of the hand wheel 41, the valve element will, be rotated with a very great reduction of movement so that the valve port 42 can be adjusted very sensitively. To indicate visibly the position of the valve or the size of the opening of the port 42, a dial finger 48 is provided on the worm gear 45 and a dial 49 having a position-indicating scale 59 thereon is supported by a bracket on the conduit 1. If desired, to cause the scale to be uniform, the port 42 in the valve element 43 may be correspondingly shaped as is well understood by those skilled in the art.

-With an apparatus of the class above described, comprising the freezing andthardening chamber 24, if the ice cream flows to and through the chamber 24 at too great a rate, it will not be hardened sufliciently, and due to the relatively short time that the ice cream remains in the chamber 24, the air; will not be thoroughly incorporated therein. Again, if the ice cream moves too slowly through the chamber 24, it may harden so "rapidly as to become substantially solid and prevent rotation of the shaft 32 by the motor 22 and stop the process.

-As stated above, an air inlet valve ll isprovided. It is common practice in'the manufacture of ice cream for various purposes such as to improve the unpalatability thereof to mix or incorporate into the ice cream a certain amount of air. Inasmuch as this increases. the volume of the In order that the correct amount of air shall be admitted and accurately controlled, I provide the following means illustrated particularly in Figs. 1 and 4.

The housing HA of the valve H is provided with an air inlet duct 52 and a valve seat 53 therein. A boss 54 is formed on the outside of the housing A and a longitudinally movable valve 55 is threaded therein having a needle point controlling the valve seat 53. The stem 56 of the needle valve is packed by a gland packing 5? which may be of well known construction. Secured to the valve stem externally of the gland is a dial finger 5B which, upon rotating the needle valve, may be moved back and forth over a dial 59 having a position-indicating scale thereon, the dial being secured by a bracket 60 to the housing A. i

The effective size of the duct 52 maybe varied by rotating the valve 55 and the size ofthe opening may be indicated by the dial finger 58 on the dial 59. The suction of the pump I3 draws air through the duct and the pump mixes the air with the liquid ice cream. The air is further incorporated and mixed with the ice cream by the agitation above described occurring in the chamber 24.

By means of my invention above described, both I the rate of flow and the overrun may be controlled and by means of the indicating scales which indicate the positions or adjustments of the valves, they may with no difllculty be kept in corresponding adjustment. For example, if the valve '8 is adjusted to any given rate of flow, the dial finger 48 will indicate, a certain definite scale point onv the dial 49 and the dial 59 may be calibrated with respect to the dial 49 so that its indicating dial finger 58 may be at once moved to a point on the dial59 corresponding to the said point on the dial 49, and thus the overrun can be instantly readjusted for anyadjustment of the valve 8 at any time without experimentation.

Thus it will be apparent that for any given set of conditions including the recipe used for making the ice cream mix, the temperature of the ice cream when it arrives at the chamber 24, the.

pumping characteristics of the pump, and any changes which may occur from time to time therein, there will be a certain predetermined quality, hardness and texture of ice cream extruded from the nozzle; and I find that the desired quality may be maintained by controlling the rate of flow. This is accomplished by adjusting the valve 8 to reduce or increase the rate at which the liquid ice cream may be permitted to fiow to the pump l3, Likewise, for-any change of flow rate of ice cream eifected by the valve 8, the valve Il may be correspondingly adjusted to correspondingly vary the amount of air admitted because for each rate of flow there will be an ideal "over-run.

The valve ll, above referred to in the conduit portion l6 comprises a housing 6| having therein a valve port 62 partly closed by a cone valve 63, thus providing some restriction in the conduit line and resistance to flow of the frozen ice cream. By this means the ice cream is compacted or COD. densed or held back by a predetermined amount to insure that the ejected ice cream will be of the proper consistency and to establish in the freezer l5 at least a minimum pressure to insure proper agitation bf the material therein and incorporation of the air thereinto. The valve 63 may be adjusted to vary the restriction by varying the size of the valve port 62, to this end the valve having a threaded stem 64 thereon extending outwardly through a gland B5 in the wall of the housing 6|. A hand wheel 66 is provided to turn the stem to adjust the valve.

By this means, the ice cream may be compacted just before it reaches the nozzle IBA so that when it is extruded in the form of a worm, the worm will be a solid well-filled worm without breaks, cavities or the like.

It has been found by experience that the ideal back pressure or opposition eflected by the valve I 1 depends upon the rate of flow at which the ice cream fiows through the freezer l5 and upon the beating thereof by the agitating elements 40 and 4| which obviously will be prolonged if the rate of flow is slow and vice versa.

It therefore becomes desirable to adjust the opposition of the fiow opposing valve I! in 'accordance with changes in the adjustment in the rate of flow. In order that this may be effected immediately and without experimentation,- a dial finger 68 is mounted on the hand wheel 66 and moves over a scale 69 supported on a bracket Ill on the housing 6 I; and as will now be understood from the more complete description hereinbefore of the air intake valve, the dial 69 may be calibrated initially by experimentation, and in respect 7 to the dials 49 and 59 so that for any position of the dial finger 48 on the dial 49 of the flow controlling valve, the dial 49. will indicate a corre-' spondi'ng position on the dial 69 for the dial finger 55. I I

For convenience, the dial 49 of the flow controlling or obstructing valve, may be provided with three dials, one the dial 49 indicating'the positionof the flow control valve 8 itself; another, 59', beinga reproduction of the dial 59; and the third, 59', being a reproduction of the dial 69. By this arrangement, whenever the flow control valve I! is adjustably moved, its dial finger 48 will indicate on the dials 59' and 59 the adjustment to which the

dial fingers

58 and 68 should be moved to correspond.

As will now be apparent, the final result desired is an extruded worm from the nozzle I9 which wlll'be of a suitable degree of form-sustaining hardness, and which will be compacted and full, and which will have the desired amount of overrun therein. The compactness may be controlled by the valve II, the overrun by the valve II, and the degree of hardness by the valve 8; and while the scales indicating the positions of these three valves are not absolutely essential in the practice of my invention, they greatly improve and facilitate the operation of the system and enable the corresponding adjustment of the three valves to be effected quickly, efliciently and without loss by experimental or cut-and-try methods.

In the foregoing description, I have particu larly described my invention as applicable to producing a suitable form-sustaining worm from liquid ice cream mix. It willbe apparent that my invention may be practiced with plastic ice cream introduced to the conduit 4 instead of liquid mix.

. In such use of my invention, the tank I would be replaced by a reservoir suitable to receive abatch of plastic ice cream which had been partly frozen.v in a suitable ice cream freezing machine;

or the plastic ice cream frozen sufliciently to render it of plastic condition may be fed to thetank I through the conduit IA. From that point on, the plastic ice cream will flow through the system as described above for liquid mix. In such case,

the plastic ice cream will be hardened in the partly frozen, it may flow through the chamber chamber 24 and the air will be mixed therewith partly in the pump 23 and partly in the chamber 24. In such case, since the ice cream is already 24 at a higher rate than in the first'described case and the valve 8 may correspondingly be adjusted to a wider opening and the, scales on the several instruments may be calibra d to correspond to such greater opening of the valve 8 in a manner that will now be understood.

The auxiliary'tank 5 may be used when it is desired to rurpa sample or special batch of ice cream through the apparatus as distinguished from the continuous production obtained when the tank I is utilized, continuously supplied.

through the conduit IA. To utilize the auxiliary tank 5, it will be understood that the valve 2 may be closed and'the valve 3 opened and vice versa.

As will now be apparent, the valve 8 can be adjusted for a rate of flow in accordance with the temperature at which the refrigerating system will maintain the freezer I5, so that whatever the temperature of the freezer may be, the apparatus may be quickly adjusted to produce frozen ice cream of the desired consistency and hardness. A given set of apparatus parts, therefore, as above described may be manufactured and installed in, various plants having refrigerating apparatus and can produce ice cream at a high rate if the plant can supply a large degree of refrigeration or at a slow rate if its refrigeration available is limited. For example, I have found that with a freezer having a freezing chamber approximately 7" inside diameter and 30" long, and with a corresponding size of motor and pump, it can be adjusted to deliver frozen ice cream at rates varying from to 300 gallons per hour, depending as above described upon the I duce ice cream at all, because such machines have not been constructed to adjust the flow rate, air admission, and back pressure to the temperature available.

As stated above, no regulation of temperature is necessary. In refrigerating plants supplying refrigeration for ice cream freezing with the above described apparatus incidental to the other uses of the refrigerating plant, changes of temperature at the freezer I5 will occur slowly or gradually and an attendant at the apparatus can detect changes in the ejected ice cream and correspondingly change the adjustment of the controls to maintain a uniform consistency of ice cream. But if desired, a temperature regulator may be employed in the line of the pipe 28 as indicated at I39. This regulator may comprise a sylphon-operated valve controlled by a bulb I 40 in thermal engagement with the conduit 28 to control the flow of refrigerant therethrough to maintain the temperature constant. Such control valves are so well known in the art'that no description or illustration thereof other than that referred to is deemed necessary.

If due to any unforeseen cause or to lack of proper supervision, the flow rate should be decreased and the temperature should fall so that the ice cream in the freezer I5 should freeze solid thawed and the apparatus has started again,

the valve may be reversely operated to restore the normal refrigeration to the freezer.

As a modified form of adjusting the controls above described, the arrangement shown in Fig. 7 may be employed. The shaft of the worm 46 may be extended as shown at I44 and may be provided with a sprocket wheel I45 on the end thereof. The stem of the needle valve 55 may have a sprocket wheel I 46 thereon connected to thesprocket wheel I45 by a chain I41. The extension I44 may have a sprocket wheel I49 on the end thereof connected by a. sprocket chain I50 with thesprocket wheel I5I on the stem 64 of the valve II. By this construction when the handle 41 of thevalve 8v is adjustably turned, it will correspondingly adjust the other two valves. By suitable ratios of the bevel sprocket wheels, the adjustable settings of the air valve and back pressure valve may be made corresponding in I each case to the setting of the flow valve so that when the flow valve is changed the other two valves areautomatically correctly changed.

When this arrangement is employed it will be apparent that the entire apparatus may be adjusted by a single hand wheel 41 to cause it to produce ice cream of the desired hardness for any temperature which may occur at the freezer, and for a given apparatus for any. temperature available in any plant where it may be installed.

It will be understood, of course, that the bare parts and conduits illustrated may be heatinsulated and that the various pipes and conduit joints .may be of the sanitary type adapted to be readily taken apart to be cleaned, such elements being well known in the art.

My invention is not limited to the exact details of construction illustrated and described. Many changes and modifications may be made within the scope and spirit of my invention without sacrificing its advantages and within the scope of the appended claims.

I claim:

.1. In a continuous ice cream manufacturing apparatus, a continuous supply source of ice cream mix, a positive displacement pump," a power source for driving the pump at constant speed, a freezer having a discharge outlet, interconnecting conduit means whereby the mix may be continuously pumped from the supply source through the freezer and discharged in frozen consistency from the outlet, a source of refrigerant at variable temperature, means to refrigerate the freezer therefrom to variable freezing temperature, a flow" restricting valve between the mix source and the pump on the intake side thereof adjustable to commensurate the rate of mix flow to the freezer temperature to cause the discharged ice cream to be of substantially the same frozen consistency at all freezer temperatures.

2, In a continuous ice cream manufacturing apparatus, a continuous supply source of ice cream mix, a positive displacement pump, a power source for driving thepump at constant speed, a freezer having a discharge outlet, interconnecting conduit means whereby the mix may be continuously pumped from the supply source through the freezer and discharged in frozen consistency from the outlet, a. source of refrigerant at variable temperature, means to refrigerate the freezer therefrom 'to variable freezing temperature, a flow restricting valve between the mix source and the pump on the intake side thereof adjustable to commensurate the rate of mix flow to the freezer temperature to cause the discharged ice cream to be of substantially the same frozen consistency at all freezer temperatures, and an air admission valve for admitting air'into the conduit means on the suction side of the pump and comprising means for adjustably fixing the rate of air admission.

3. In a continuous ice cream manufacturing apparatus, a continuous supply source of ice cream mix, a positive displacement pump, a

power source for driving the pump at constant speed, a freezer having a discharge outlet, interconnecting conduit means whereby the mix may be continuously pumped from the supply source through the freezer and discharged in frozen consistency from the outlet, a source of refrigerant at variable temperature, means to refrigerate the freezer therefrom to a variable freezing temperature, a flow restricting valve between the mix source and the pump on the intake side thereof adjustable to commensurate the rate of mix flow to the freezer temperature to cause the discharged ice cream to be of substantially the same frozen consistency at all freezer temperatures, an air admission valve for admitting air into the conduit means on the suction side of the pump and comprising means for adjustably fixing the rate of air admission, and a flow restricting port on the conduit means between the freezer and the outlet for creating back pressure in the conduit means and means for adjustably fixing the area of the restricting port.

4. In a continuous ice cream manufacturing apparatus, a source of supply of ice cream mix, a positive displacement pump, a power source for driving the pump at constant speed, a freezer having a discharge outlet, interconnecting conduit means whereby the mix may be pumped from the supply source through the freezer and discharged in' frozen consistency from the outlet, a source of refrigerant, means to refrigerate the freezer from the source, a flow restricting valve between the mix source and the pump onthe intake side thereof to adjust the rate of flow of the 'mix to determine the frozen consistency of the discharged ice cream.

5.'In a continuous ice cream manufacturing apparatus, a source of supply'of ice cream vmix,

' a positive displacement pump, a power source for driving the pump at constant speed, a freezer having a discharge outlet, interconnecting conduit means whereby the mix may be pumped from the supply source through the freezer and discharged in frozen consistency from the outlet, a

' source of refrigerant, means to refrigerate the freezer from the source, a flow restricting valve between the mix source and the pump on the intake side thereof to adjust the rate of flow of the mix to determine the frozen consistency of the discharged ice cream, and an air admission valve for admitting air to the intake side of the pump and means to adjustably fix the rate of air admission.

6. In a continuous ice cream manufacturing apparatus, a source of supply of ice cream mix, a positive displacement pump, a power source for driving the pump at constant speed, a freezer having a discharge outlet, interconnecting conduit means whereby the mix may be pumped from the supply source through the freezer and discharged in frozen consistency from the outlet, a source of refrigerant, means to refrigerate the freezer from the source, a flow resticting valve between the mix source and the pump on the intake side thereof to adjust the rate of flow of the mix to determine the frozen consistency of the discharged ice cream, and an air admission valve for admitting air tothe intake side of the pump and means to adjustably fix the rate of air admission, and a restriction port in the conduit means between the freezer and the discharge outlet for creating back pressure in theconduit means, and means to adjustably fix the area of the restriction port.

'7. In an ice cream continuous freezing apparatus, a freezer having a discharge outlet, a posioutlet, means for refrigerating the freezer to cause the discharged icecream to be of frozen consistency, a flow rate valve between the pump and the source for adjustably restricting the rate of flow, an air admission valve on the intake side of the pump for admitting air from the atmosphere, and adjustable to fix the rate of admission, a flow restriction valve between the freezer and the discharge outlet for creating back pressure in the conduit means and adjustable to fix the amount of restriction, and determining means to cause a setting of the flow rate control valve to determine a corresponding independent setting of the air admission valve and the back pressure valve, said setting indicating means comprising indicating scales on the flow control valve indicating correspondingsettings for the air admission valve and the back pressure valve, and position indicating scales for said air admission valve and back pressure valve by which they may be independently set to said indicated positions.

8. In an ice cream continuous freezing apparatus, a freezer having a discharge outlet, a positive displacement pump, a power source for driving the pump at constant speed, a source of liquid mix interconnecting conduit means whereby liquid mix may be continuously pump from the source through the freezer and out at the outlet, means for refrigerating the freezer to cause the discharged ice cream to be of frozen consistency, a flow rate valve between the pump and the source for adjustably restricting the rate of flow, an air admission valve on the intake side of the pump for admitting air from the atmosphere, and adjustable to fix the rate of admission, a flow restriction valve between the freezer and the discharge outlet for creating back pressure in the conduit means and adjustable to fix the amount of restriction, and mechanical interconnections between the said flow rate valve, air admission valve and back pressure valve whereby upon adjustably setting the flow rate valve, the air admission valve and back pressure valve will be correspondingly adjustably set.

9. The apparatus described in claim 4 and in which the freezer comprises an agitator driven by the power source at constant speed.

10. The apparatus described in claim 5 and in which the freezer comprises an agitator driven at constant speed by the power source.

11. In a continuous material congealing apparatus, a source of supply of liquid or semiliquid material to be congealed, a positive displacement pump, a power source for driving the pump at constant speed, a congealing apparatus comprising a chamber having a discharge outlet, interconnecting conduit means whereby the material may be pumped from the supply source through the chamber and discharged in congealed consistency from the outlet, a source of refrigerant, means to refrigerate the chamber from the refrigerant source, a flow restricting valve between the material source and the pump on the intake side thereof to adjust the rate of flow of the material to determine the hardness of the discharged congealed material.

12. In a continuous material congealing apparatus, a source of supply of liquid or semiiiquid material to be congealed, a positive .displacement pump, a power source for driving the pump at constant speed, a congealing apparatus comprising a chamber having a discharge outlet, interconnecting conduit means whereby the mix may be pumped from the supply source through the chamber and discharged in congealed consistency from the outlet, a source of refrigerant, means to refrigerate the chamber from the refrigerant source, a flow restricting valve between the material source and the pump on the intake side thereof to adjust the rate' of flow of the material to determine the hardness of the discharged congealed material, and an air admission valve for admitting air to the intake side of the pump and means to adjustably fix the rate of air admission.

13. In a continuous material congealing apparatus, a source of supply of liquid or semiliquid material to be congealed, a positive dis- I placement pump, a power source for driving the pump at constant speed, a congealing apparatus comprising a chamber having a discharge outlet,

, interconnecting conduit means whereby the mix may be pumped from the supply source through the chamber and discharged in congealed consistency from the outlet, a source of refrigerant, means to refrigerate the chamber from the refrigerant source, a flow restricting valve between the material source and the pump on the intake side thereof to adjust the rate of flow of the material to determine the hardness of the discharged congealed material, and an air admission valve for admitting air to the intake side of the pump a source at constant speed.

15. The apparatus describedin claim 12 and in which the congealing apparatus comprises an agitator in the chamber driven at constant speed by the power source. 1

16. In a continuous material congealing apparatus, a source of supply of liquid or semlliquid material to be congealed, a positive displacement pump, a power source for driving the pump, a congealing apparatus comprising a chamber having a discharge outlet, interconnecting conduit means whereby the material may be pumped from the supply source through the chamber and discharged in congealed consistency from the out1et, a source of refrigerant, means to refrigerate the chamber from the refrigerant source, afiow restricting valve between the material source and the pump on the intake side thereof to adjust the rate of flow of the material to determine the hardness of the discharged congealed material.

1'7. In a continuous material congealing apparatus, a source of supply of liquid or semi-liquid material to be congealed, a pump, a power source for driving the pump at constant speed, a congealing apparatus comprising a chamber having a discharge outlet, interconnecting conduit means whereby the material may be pumped from the supply source through the chamber and discharged in congealed consistency from the outlet, 8. source of refrigerant, means to refrigerate the chamber from the refrigerant source, a flow restricting valve between the material source and the pump on the intake side thereof to adjust the rate of flow of the material to determine the hardness-of the discharged congealed material.

18. The apparatus described in claim 16 and in which the congealing apparatus comprises an agitator in the chamber driven by the power source.

19. The apparatus described in claim 17 and in which the congealing apparatus comprises an agitator in the chamber driven by the power source at constant speed.

20. In a continuous material handling apparatus, a continuous source of supply of fluid material, a pump, a power source for driving the pump, refrigerating apparatus having a discharge outlet, inter-connecting conduit means whereby material may be pumped from the supply source through the said refrigerating apparatus and discharged in a state of increased consistency from the outlet, a source of refrigerant, means to communicate said refrigerant to the refrigerating apparatus to lower its temperature, flow restrict ing means between the material source and the pump to adjust the rate of flow of the material to regulate the consistency of the discharged material.

21. In a continuous material handling appara'- municate said refrigerant to the refrigerating apparatus to lower its temperature, and flow restricting means between the material source and pump to adjust the rate of flow of the material to regulate the consistency of the discharged material.

ALMOND C. ROUTH.