US2036217A - Ice cream freezer - Google Patents

Description

PI 7, 193@ R. H. JORDAN 2,036,217

ICE) CREAM FREEZER Filed April l2, 1934 Patented Apr. 7, 1936 UNITED STATES PATENT' OFFICE ICE CREAM FREEZER of Pennsylvania Application April 12, 1934, Serial No. 720,221

4 Claims.

My invention relates to ice cream freezers, and it haaparticular relation to improvements in the construction of freezers adapted for use in electric household refrigerators.

One satisfactory form of cream-freezing device capable of deriving the necessary cooling from the evaporator or ice-making compartment of a domestic refrigerator comprises a cream container equipped with an agitator adapted to be driven by an electric motor which preferably is attached to the container assemblage and arranged to derive energization from the refrigerator supply circuit. Within my knowledge, however, all such freezing devices which have been utilized in the past have been subject to a number of operating difliculties, and it is to the overcoming of these difficulties that the present invention is directed.

Generally stated, the object of my invention is to improve the construction of freezers of the type under consideration.

A more specific object of my invention is to facilitate the removal of the agitator from the body of the solidiiied cream upon the completion of the freezing operation.

Another object of my invention is to provide improved means for breaking loose the restraining bond of ice which, during the freezing operation, forms between the freezer structure and the surface of the evaporator or ice-making compartment upon which it rests.

My invention, itself, together with additional objects and advantages, will best be understood -through the following description of specific embodiments thereof when taken'in conjunction with the accompanying drawing in which:

Figure' l is a side elevational view, partially in section, of an ice cream freezer incorporating the improvements of my invention.

Fig. 2 is a view in end elevation of the device of Fig. i.

Fig. 3 is a view of the open end of the cream container of the device of Fig. l showing the improved agitator of my invention installed therein.

Fig. 4 is a view in side elevation showing the manner in which the two assemblages comprised l by theagitating device represented in Figs. 1 and 3 may be separated from each other.

Fig. 5 is a perspective view of the loosening member of my invention when removed from the freezer structure, and

Fig. 6 is a diagrammatic view of a preferred form of control system for the driving Y'motor which formsa part of the illustrated freezer.

Referring to the drawing, the freezer structure, there illustrated comprises a cylindrical container I0, adapted to receive the cream or other material to be frozen, the open end of which container may be closed by a detachable lid or cover 5 I2. To this cover is removably secured a gear casing I4 carrying an electric moto-r IB which drives, through suitable reduction gearing housed inside of the casing, an agitator or stirring-assemblage IB disposed inside of the container. 10 The entire freezer structure is designed for lengthwise insertion into the ice-making compartment of a domestic refrigerator (not shown) an energizing circuit for the motor being established through a flexible cord 22 terminating in i6 a plug connection 24 which may be inserted into an outlet receptacle conveniently located, as on an interior wall of the refrigerator.

The motor I6 drives, at a suitably reduced speed, a shaft 32 which is provided with an end 20 projectingftongue portion 33 which fits into a similarly shaped recess in the end 34 of the shaft which forms a part of the agitator I8. This agitator shaft is carried by suitable journals or bearings 36 and 38 formed respectively in the 25 closed end of the cream container I0 and in the container cover I2.

When disassembled, the illustrated freezer comprises four separate parts or assemblages; the mixture container Ill, the agitator I8, the re- 3c movable cover I2 and the gear casing and motor assemblage III-I6. To hold the cover firmly in place against the container end and to enable its ready detachment', a plurality of spring clamping members 26 are utilized to hook over the 35 cover edge in the manner shown, the seal being made liquid tight through the use of a gasket 4|] of rubber or other resilient material. Attachment of the motor and gear casing assemblage II--IG to the cover plate I2 is eifected 40 by means of a circular recess in the plate side in which recess the end of the casing I4 is held at the bottom by means of a small plate member 45 and at the top by means of a vertically movable latch device 41 carried' by the cover plate. 45

Upon the completion of the cream-freezing operation, it is desirable to remove the agitator structure to facilitate a proper packing of the frozen mixture and to enable the mixture to be readily dipped out for consumptive purposes. In all previous designs of agitators with which I am familiar, such removal necessitates, particularly in the case of the relatively small capacity containers comprised by refrigeratortype devices. a removal of a substantial portion of the frozen mixture, which removed portion must be replaced in the container and properly packed, an operation which is laborious and wasteful of time. To overcome this disadvantage, I have designed an agitator which comprises two separable assemblages only one of which need be removed upon the completion of the freezing operation.

As illustrated in the drawing, the complete structure comprises the central driving shaft 90 and one or more stirring members 92 which are held in contact with the wall of the container I0 by means of cross bar members 94 and 96. As hereinbefore explained, the motor I6 is coupled with shaft 90 through the gear box i4 so that when operated it functions to rotate the agitator at a proper rate of speed. s

One of the named assemblages comprises the cross-bar member 94 and the stirring blades 92k into a suitably shaped recess |04 in the end of one of the blades.

Likewise a driving connection between the shaft 90 and the cross-bar 94 of the rst named assemblage is effected by making the cooperating section of the shaft of hexagonal or other nonround contour and providing the cross bar with a similarly shaped opening |00 into'which the shaft is adapted to llt. Both of these connections permit the cooperating members to slide axially relative to each other so that the second named assemblage may readily be withdrawn from the first, as is shown in Fig. 4.

Upon the completion of the cream-freezing operation, vonly the outer cross bar 96 and the drive shaft 90 need be withdrawn from the container, the inner cross bar 94 and the attached paddle members 92 being allowed to remain embedded in the solidified mixture. As a result, no dimculty whatever is experienced in packing the cream, since practically none of it need be removed. Furthermore, because of the fact that the blades 92 and the inner-cross bar 94 are adjacent the sides and bottom of the cream container, respectively, their presence in no way interferes with a subsequent removal of the ice cream. The described two-part construction for an agitator is, therefore, one of considerable merit and utility.

It will be understood that my improved agitator is not restricted in its application to freezers of the small-capacity refrigerator type with which it has been illustrated, since it is apparent that it may, with equal success, be applied to mixture-soldifying devices of practically all sizes and types.

During the freezing operation, it is found that there forms between the lower portion of the freezer structure and the supporting shelf member, represented at 16, upon which it rests, a film or thin layer of ice which frequently is difficult to break when it is desired to remove the structure from the refrigerator compartment. To overcome this diinculty, I provide means for readily breaking this restraining bond of ice,

which means preferably comprises a cam member 60 carried by a shaft 62, the protruding end of which fits into a journalled hole 64 at one side of the cover-accommodating face of the creamcontainer base structure. The other end of this shaft carries a handle 66 which extends upwardly along one side of the motor i6 or which occupies some other position of ready accessibility.

When the illustrated handle 66 is moved toward the motor i6, the cam 60 is rotated and forced downwardly into contact with the freezersupporting shelf member 16, an action which loosens the freezer structure from the restraining ice bond. The bond having been broken, removal of the freezer is readily effected.

The illustrated loosening device possesses the advantage of being readily removable from the freezer structure with which it is used. When installed, as shown in Figs. 1 and 2, it is held in position by means of a suitable edge extension 66 (see Fig. 2) of the cover I2 adapted to overlap the loosener cam. Removal of the cover from the container thus allows the shaft 62 to be withdrawn from the journalled hole 64 so that the complete loosener assemblage, shown in Fig. 5, may be separated from the related freezer mechanism. This feature is of distinct advantage in facilitating the washing of the cream container and cover assemblages. The design illustrated is further unique in that it permits the user to grasp the handle 66 and the motor I6 and by forcing them toward each other readily produce the necessary force for breaking the ice bond.

The freezer structure thus far described is, exclusive of the improved agitator and loosener, similar to that disclosed and claimed in my copending application, Serial No. 686,762, filed August 25, 1933, and assigned to the same assignee as is this invention. That application further explains and claims the use of an intermittent-energization control system for the agitator driving motor, which system functions to reduce the effective heat losses dissipated during operation and thereby allows, without appreciably burdening the cooling capacity of the refrigerator in which the freezer is used, the use of a motor sufficiently strong to continue an intermittent agitation of the mixture until it has been almost completely solidified.

In the effecting of such intermittent control, the use of a timing device in the form of a thermostat equipped with a heater has been found especially satisfactory since such a combination may be made completely automatic in its operation and further is susceptible of time-on to timeolf adjustment through a relatively wide range. Thus one preferred form of such control equipment comprises a thermostat, diagrammatically represented at 60 in Fig. 6, which is surrounded by a suitable casing, represented at 6| in Figs. 1 and 2, which casing is shown as being suspended from the lower side of the gear box I4.

'I'he represented thermostat comprises a bimetallic disc 62 which, in the downwardly curved position illustrated, biases movable contact members 64 into engagement withstationary contact members 66 to thereby complete an energizing circuit for the motor I6. Such circuit completion also energizes a resistor 60 which heats the disc and causes it to reverse its curvature with a snap action. The resulting disengagement of the thermostat contacts discontinues energization of the motor and heater. When the disc temperature again drops to a given low value. the disc lil snaps back to the illustrated position and thus causes the described cycle to be repeated.

Preferably each period of motor energization is of the order of three or four seconds while each period of deenergization is of the order of three or four minutes. For thermostats of commercially available design, I have found that when the illustrated mounting below the gear box structure is utilized, which location is desirable since it provides a unitary construction for the motor and its control means, the cooling of the thermostat disc does not proceed as rapidly as is necessary to effect the above specified cycle.

'Io overcome this difficulty, I increase the rate of disc cooling by attaching to the lower surface of the thermostat casing il i, which casing is preferably of molded insulating material, a plurality of metallic button members 'it and support this casing from the gear box structure by means of screws if adapted to permit of a sliding movement along their length.r Compression springs 'it then bias the casing downwardly and thereby maintain the button members lil in contact with the supporting shelf member 'it of the evaporator or ice-making compartment upon which the freezer rests, as shown in Fig. 2. Upon endwise insertion into the compartment, a beveled portion it assures that the casing will be forced upwardly to the shelf-contacting position illustrated.

By virtue of this contact the heat storedin the thermostat disc B2 is effectively dissipated to the relatively cold shelf 'i6 and the desired cycle of intermittent motor control is thereby effected with thermostatic devices of commercial design. It will he understood that this expedient is the equivalent of mounting the thermostat tt in direct contact with the cream container it for example. It possesses, however, the before-named advantage of providing a unitary construction for the motor and its control means and hence, in practice, is of utility.

Although I have shown and described certain specific embodiments of my invention, I am fully aware that many modifications thereof are possible. My invention, therefore, is not to be restricted except insofar as is necessitated by the prior art and by the scope of the appended claims.

I claim as my invention:

1. In combination with an ice-cream freezer adapted to be supported by the cooling unit of a refrigerator, said freezer comprising a. container structure and a. removable cover member therefor, means for breaking ice which may form between the freezer and the cooling unit surface upon which it rests, said means comprising a. shaft, a journalled opening near the bottom of said container structure for receiving one end of said shaft, a. cam can'ied by the protruding portion of said shaft, and a handle for rotating the shaft to cause said cam to bear against the said cooling unit surface, the positioning of said journalled opening being such that an e of said cover member when installed, overlaps said cam to prevent said shaft from being withdrawn from the opening.

2. In combination with. an ice-cream freezer adapted to be supported by the cooling unit of a refrigerator, said freezer comprising a container structure anda removable cover member therefor, means for breaking ice which may form between the freezer and the cooling unit surface upon which it rests, said means comprising a shaft, a journalled opening near the bottom of said container structure for receiving one end. of said shaft, a cam carried by the protru portion of said shaft, and a handle for rotating the shaft to cause said cam to bear against the said cooling unit surface, the positioning of said journalled opening being such that a removal of said cover member, one edge of which overlaps said cam, allows said shaft to be withdrawn from. the opening.

3. In combination with an ice-cream freezer adapted to be supported by the cooling unit of a. refrigerator, said freezer comprising a container, an. agitator therein, a detachable cover therefor, an electric motor carried by said cover, and structure for operatively connecting the motor with the agitator, .the combination of a motor-control thermostat supported from the lower portionof said structure, a casing for said thermostat, and means for biasing said casing into contact with the cooling unit surface upon which the freezer rests.

4. In combination with an ice-cream freezer adapted to be supported by the cooling unit of a refrigerator, said freezer comprising a container, an agitator therein, a detachable cover therefor, an electric motor carried by said cover, and

structure for operatively connecting the motor.

with the agitator, the combination of a' motorcontrol thermostat provided with a, heater, a casing surrounding said thermostat and heater means for supporting said casing from the lower portion of said structure, and means for biasing said casing into Contact with the cooling unitsurface upon which the freezer rests to enhance the transfer of heat thereto.

RICHARD H. JORDAN.

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