US2221694A

US2221694A - Ice-making apparatus

Info

Publication number: US2221694A
Application number: US201246A
Authority: US
Inventors: Thomas I Potter
Original assignee: Individual
Current assignee: Individual
Priority date: 1938-04-11
Filing date: 1938-04-11
Publication date: 1940-11-12
Anticipated expiration: 1957-11-12

Description

NGV. 12, 1940. l i T, I POTTER 1 v A2,221,594 v ICE-MAKING APPARATUS I Filed vApril 11, .1938

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v INVENTOR YZ0/m51'. Porn-R ATTORNEY Patented Nov. 12, 1940 UNITED STATES PATENT foFFlcE y 2,221,694 ICE-MAKING APPARATUS f Thomas I. Potter, Buffalo, N. Y.

Application April 11, 1938, Serial No. 201,246

4 Claims.

The present invention relates to improvements in ice-making apparatus, and more particularly to apparatus of the type in which ice blocks are formed at or near the bottom of a tank of water and then are released and floatedv to the surface of the Water. Y

In my copending application Serial No. 130,432, filed March 12, 1937, I describe an ice-maker of this general type which is connected into the l0 refrigerating circuit of a household refrigerator, operating on an intermittent cycle, the ice blocks being formed during the on period of the refrigerating cycle and being released and floated to the surface during the off period.` Most household refrigerators operate on an intermittent cycle in which the on period is of suiiicient duration to freeze the ice blocks and the off period is also of sufcient duration to free the Y ice blocks from their molds. Obviously, however, the ice-making apparatus described in said copending application would not be suitable for use with a refrigerating circuit operating continuously.y nor for one operating intermittently at such frequency that the-on period would be too short to form blocks of ice or the off period too short to release the blocks. It is, therefore,`

an object of the present invention to provide an ice making apparatus with an off and on control making it feasible to connect its refrigerating circuit in series or parallel with a continuously operating refrigerating circuit or with van intermittently operating refrigerating circuit of comparatively high frequency.

One object of my invention is to provide an apparatus of this character with means for controlling the size of the ice blocks formed.

It is a further object of my invention to provide means for supplying heat to the ice molds at proper intervals and in sufficient quantity to eifect a quick release of the ice blocks.

Another object of my invention is to provide automatically operating means for interrupting the freezing of the ice blocks and releasing the same from their molds.. Still another object is to provide thermally controlled means for this DUYPOSB- Other objects and advantages of my invention will appear in the following description and claims.

In the accompanying drawing:

Fig. l is a plan view of an ice-making apparatus embodying this invention and attached to a household refrigerator, the latter being shown fragmentally and in section.

Fig. 2 is a fragmentary transverse vertical sec- (Cl. 62-105) l tional elevation thereof on an enlarged scale on line 2-2, Fig. l.

Fig. 3 is a central sectional View of an end portion of an electric heating element which may be used on my ice-making apparatus. 5

Fig. 4 is a transverse section thereof on line 4 4, 3.

Fig. 5 is a fragmentary longitudinal sectional elevation of another form of ice-making apparatus showing other means for releasing ice i0 blocks formed by means of the apparatus.

Fig. 6 is a sectional bottom plan view on line 6--.6, Fig. 7, of a time-controlled means for use in connection with my improved ice-making apparatus and this figure shows diagrammatically 15 the electrical connections between the time controlled means and other parts of the ice-making apparatus.

Fig. '7 is an elevation of the time-controlled means shown in Fig. 6. 20

Fig. 8 is an elevation, partly insection, of a household refrigerator having an ice block making device embodying this invention.

Fig.. 9 is a wiring diagram connecting the on and off control of the ice making apparatus 25 with the thermostatic control of a household refrigerator.

In Fig. l, I show at I a portion of a household refrigerator which. it will be understood, is

' equipped with a refrigerating system operating 30 either continuously or intermittently. I'he operating mechanism of this refrigerator and the cooling unit or units provided therein are not shown, but two pipes of the refrigerant circuit are shown at Il and I2 respectively. Pipe II 35 may be on the high pressure sideof the circuit and pipe I2 on the low pressure side. I have also shown in Fig. 2 a refrigerating machine or compressor I3 driven by an electric motor I4, which may form apart of the refrigerating sys- 40 tem employed in connection with the refrigerator Attached to one of the refrigerator walls and on the outside thereof, is an ice-making device incorporating one embodiment of this invention. 45 This device comprises an outer shell I5 and an inner shell I8 between which there is a packing I1 of insulation material. The insulation material is supported under the shell I8 by the bottom wall of the shell I5.

The inner shell I6 which constitutes a water tank, is provided with suitable molds for ice. These molds may be of any suitable form or construction and may be portions of the bottom of the tank I6. By way of example. I have provided the bottom of the water tank with depending ice molds preferably arranged in two rows, with the molds of onerow staggered with respect to those of the other row. These molds are shaped so that when ice blocks are formed therein and released from adhesion to the walls of the molds by melting, they will float to the surface of the water in the tank. For example, the molds may be of inverted conical form and are formed of metal having high thermal conductivity.

The molds in the'particular construction illustrated are refrigerated by means of a U-shaped refrigerant conduit or line, one leg 2| of which is connected to one row of molds at the bottom thereof and the other leg 22 to`the other row of molds. The conduit having these legs 2I and 22 may be cut into the line I2 either in parallel or in series with the cooling unit of the refrigerator. In the embodiment illustrated, a series connection is provided which may be either at the intake or the outlet side of the cooling unit of the refrigerator I9.

Means are preferably provided for interrupting the freezing of water in the molds 20 independently of the intermittent or continuous operation of the mechanism of the refrigerator, and this may be accomplished in any suitable manner. For example, as clearly shown in Fig. 2, I provide thermostatcally controlled means for interrupting -the supply of current to the motor I4 which operates the compressor I3. The thermostatic means may be of any suitable or desired construction, and as illustrated in Fig. 2, this thermostat is provided with a bulb-like portion 24 arranged in thermal contact or in heat conducting relation to one of the molds 29. .The bulb-like portion 2li of the thermostat is connected by means of a capillary tube 25 with an expanslble member or bellows 26. The bulb contains an expansible fluid which when heated expands and in turn causes the expansion of the bellows member 28. The expansion of this member is opposed by means of a coil spring 21, the pressure of which may be varied by means of an adjusting screw 28 so that the temperature at which 'the thermostat operates the bellows 26 may be varied as desired, and the regulation of the adjusting screw 28, consequently, also regulates the size of the ice blocks formed in the molds.

The thermostatic device described may operate in any suitable manner to actuate a current controlling switch so that when the portion of the mold to which the bulb 24 is applied has a temperature of about 32 F. or more, the bellows 26 will expand and move the switch into a position to close a circuit to the motor I4. This will cause the refrigerating apparatus to operate to freeze `ice in the molds 20. When the portion of the mold to which the thermostat bulb 24 is applied becomes chilled below the freezing point of water the action of the switch is reversed so that the supply of electric current to the motor I4 is interrupted. I have illustrated diagrammatically in Fig. 2 a double pole switch 30,-the blades of which are connected by means of conductors 3| and 32 to a source of power. The blades are mounted to swing into contact with stationary switch terminals to which the ends of conductors 33 and 3Q are connected. These conductors lead to the motor I4, .and consequently, when the bellows member 25 is expanded due to heating of the fluid in the thermostatc bulb 24, the switch will be moved into position to supply current to the motor I4.

In accordance with my invention. I also provide means for releasing by meltage ice blocks formed' in the mold 29. This may be accomplished in any suitable or desired manner by supplying suilicient heat to the molds to release the ice blocks and in the particular construction shown by way of example in Fig. 2, I have provided electric heating means for this purpose. These electric heating means are arranged in heat transfer relation to leach mold and may be in the form of an electric resistance wire 31. This resistance wire 31 may be connected by means of

conductors

33 and 39 to two switch terminals which may also be engaged by the movable switch member so that after the switch member has opened the circuit to the motor I4, it will be further moved into engagement with the switch terminals to which the

conductors

38 and 39 are connected. Current will, consequently, be conducted to the resistance wire to heat the mold 20 sufficiently to release the ice block formed therein. As soon as this is accomplished the heat from the resistance coil will also raise the temperature of the bulb 24 of the thermostat so that the movable switch member 30 is again moved into position to supply current to the motor I4. Since the thermostat may be set to operate on temperature differences of comparatively few degrees, it follows that the heating of the molds will be interrupted immediately after release of the ice blocks. so that no unnecessary heating of the water in the tank results.

The electric heating means may be of any suitable construction. I have found, however, that a very satisfactory heatingunit can be formed as shown in Figs. 3 and 4. In these figures, the electric resistance wire 31 isshown as having a covering 49 of suitable electric insulating material such, for example, as woven asbestos. This insulated heating wire is drawn .through a small metal tube 4I which may, for example, be of copper and which may be soldered or otherwise arranged in good heat conducting relation to the molds 20. While asbestos* is also a heat insulator, yet since it forms a comparatively thin layer about the heating wire 31, it permits sufficient heat to pass to the copper tube 4I 'to quickly release an ice block from a mold. The ends of the tube 4I may be sealed in any suitable manner to prevent moisture from entering the interior of this tube. For this purpose, I provide at each end of the wire a suitable sleeve 42 having an enlarged end which may be filled with a suitable ceramic or refractory cement 43 through which the endof the conductor 31 extends and which excludes moisture from the interior of the tube 4I. To the ends of the heating wire 31, low resistance conductors may be connected, the two ends of the heating wire being shown connected to the conductors 3B and 39. The heating element described is desirable in that it prevents short circuits, which might be caused by moisture collecting on the outer surfaces of the molds, due

to condensation. Any other electric heating means for the molds may, of course, be employed, if desired; As clearly shown in Fig. 2, the entire outer surfaceof the mold 20 is surrounded with the heat insulating material I1.

In Fig. 5, I have shown other means for releasing the ice blocks from the molds through.

meltage, which may also be operated electrically and automatically. In this construction, the outer shell I5 arranged about the tank I6 is provided with abottom wall 45 through which at least portions of the molds 20 extend. Below this bottom wall is formed a compartment or space al l , from` the air to the molds.

in' which air may be circulated to provide sufcient heat to release the ice blocks from the molds by meltage. In the construction shown, a housing 46 is provided below the bottom wall 45 of the shell i and this housing may, if desired, contain a drip pan 41 in which water of condensation from the outer surfaces of the molds may be collected. The molds also may be provided with radiating fins or ribs 48 of any suitable or desired form to facilitate the transfer of heat The air housing 46 is provided with any suitable air inlet 56 and. with an air discharge opening 5| and a positive circulation of air through the air housing is provided in any suitable manner, for example, by means of a fan or blower 52 driven by an electric motor 53. The fan, in the construction shown, is arranged at the inlet opening 56 and the outlet opening 5| is so arranged that the air passing through the housing will contact with all of the molds, to ensure quick release of the ice blocks in all of the molds. The molds 20 are connected with a conduit 54 for refrigerant in any suitable manner, for example, as described in connectionv with the molds shown in Figs. 1 and 2.

In the operation of the construction shown in Fig. 5, the circulation of air through the air housing 46, to release by meltage ice blocks formed in the molds 20, can be controlled in the same manner as described in connection with the electric heating units shown in Figs. 2 to 4, namely by connecting the fan motor 53 to the

conductors

38 and 39 in place of the electric heating units shown in Fig. 2.

Bymeans of the construction shown in Fig. 5, air is circulated through the housing 46 only when it is desired to remove the ice blocks from the molds by meltage, at which time the fan 52 provides for an ample flow of air through the housing 46 so that the ice blocks may be readily removed from the molds. During the freezing of the ice blocks in the molds, the fan is standing idle, so that there is very little or no circulation of air through the housing 46, and consequently, the air contained in the housing 46 becomes chilled and does not interfere with the freezing of the ice blocks in the mold.

In Figs. 6 and '7, I have illustrated an arrangement whereby the thermostatic control of the ice-making apparatus may be replaced by time or clock controlled means. 60 represents a clock which may be mounted on any suitable xed support 6i which may, for example, be a part of the outer shell of the ice-making device or of the refrigerator. The clock 66 drives a contact arm 62 fwhich bears against a -commutator or circuit openingand closing device 59 having a. contact segment 63 which is .electrically connected by means of aco'nductor 464 with one terminal of a solenoid 65. The other terminal of the solenoid may be connected to one of a pair of

power lines

66 and 61, for example, the line 66, the other line 61 being connected with the contact arm 62. Consequently, when the contact arm 62 engages the segment 63 the solenoid will be energized so that a core 18 thereof will be drawn into the solenoid against the action of a coil spring 1I. This core is connected to a movable switch member 12 having two blades which are connected .respectively with the

power lines

66 and 61 by means of

conductors

13 and 14. When the solenoid is energized, the switch member 12y will be drawn into circuit closing position in iwhich the blades thereof contact-with termi-nais connected with conductors T5: and 16 leading to a motor 11 which -driyes the compressor of the refrigerating apparatus. When the contact` arm 62 moves out of engagement with the segment 6l, the solenoid will be de-energized and the spring 1| will move the core 10 outwardly, thus moving the switch 12 out of engagement with the terminals of the conductors and 16 and thus interruptingy the supply of current to the driving motor 11 of the compressor.

If the contact arm 62 is driven in counterclockwise direction indicated by the arrow in Fig. 6, the end of the contact arm 62 will contact wit', the insulation of the commutator 59 for a brief period of time after moving out of contact with vthe segment 63, and will then contact'with another segment 86 also arranged on the commutator 59. 'Ihis segment 86 in the construction shown in Fig. 6 is connected by means of a conductor 8| to suitable means for heating the molds to release the ice blocks. By way of example, I have shown in Fig. 6 a series of electric resistance wires 82, corresponding to the resistance wire 31 described in connection with Figs. 1 to 4. The other terminals of these resistance wires are connected by means of a conductor 83 to the line 66, so that if a switch 84 arranged in the conductor 83 is closed, a circuit including the heating coils 82 will be completed through the contact arm 672 and segment 86 to the other line 61'. After the contact arm 62 moves out of engagement with the segment 80, it will again contact with the insulating surface of the commutator 59 for a short period of time, whereupon it will again contact with the segment 63 to start the operation of the refrigerating system. The

segments

63 and 80 may extendin the path of movement in the contact arm 62 to'any suitable or desired extent, depending upon the length of vplace of the heating coils 82 and if the airvheat- .ing of the molds as shown in Fig. 5 is employed,

the electric motor 53 may be substituted for the heating coils 82 so that the clock controlled mechanism may provide current to the electric fmotor'53 when the movable contact arm 62 engages the segment 86.

While I have illustrated in Fig; 1 an application of my improved ice-making apparatus to a household refrigerator of ordinary construction, yet it will be obvious that it is not intended to limit my improved ice-making. apparatus to use as an adjunct'or accessory to a household refrigerator, for the reason that, if desired, my invention can readily be applied to a refrlgerating apparatus which serves solely to produce ice blocks. By way of example', I have illustrated an apparatus of this type in Fig. 8.

This refrigerator includes acabinet 96 having a lower compartment 9| containing any suitable type of heat pumping unit. -This unit may comprise a motor 92which drives a compressor- 93.

represents a condenser which receives and condenses the refrigerant compressed byv the compressor 93 and discharges the liquefied refrigerant to a receiver 95. A high pressure line 96 conveysf'reirigerant from the receiver 95 to a suitable conduit or conduits 98, which are in ther- .0 ring relation to said mold and connected with mal contact'or heat transferring relation to a series of molds 99 in the base of a tank |00 arranged in the upper portion of the cabinet. The conduit or conduits 98 may be connected to a return pipe |0| leading to the compressor. |03 represents electric heating coils also arranged in heat conducting relation to the molds 99 for releasing the ice blocks formed in the molds. 'I'he operation of this cabinet may, of course, be automatically controlled by any of the means herein described and the electric heatingcoils may also be replaced by the mold heating means shown in Fig. 5. tank |00.

In Fig. 9 I have disclosed a wiring diagram showing the contacts of the on and off control switch 30 of the ice making apparatus connected in series with the contacts of the diagrammatically illustrated thermostatically controlled switch |05 of a household refrigerator. During the on period of the on and oif" switch 30 of the ice making'apparatus, the thermostatlcally controlled switch |05 of the refrigerator controls the intermittent operation of the compressor motor in the normal way. This control of-the motor will be interrupted and superseded by the on and off switch 30 when it opens the motor circuit and closes the ice block releasing circuit but only for the short time necessary to release the ice blocks. After the ice blocks have been released the motor circuit will again 4be closed by the on and off switch 30 and the motor will again-operate intermittently under control of the thermostatically controlled` switch |05 in the refrigerator.

For the purpose of freezing ice when the refrigerator is cold and requires no refrigeration, I provide a hand switch |06 to short circuit'the thermostatically controlled switch |05 of the refrigerator and to place the motor under control of the on and olf switch 30 of the ice making apparatus.

While I have described a preferred embodiment of my invention and certain modifications thereof, it will be understood that these are to be taken as illustrative and not limitative of my invention and that I reserve the right to make various changes in form, construction and arrangement of parts without departing from the spirit and scope oi' my invention as pointed out in the following claims.

I claim as my invention:

1. An ice-making apparatus adapted to be used as an Aadjunct to a refrigerating system having a refrigerant circuit operating on an intermittent high frequency cycle, said apparatus comprising a water tank provided with thermally' insulated walls and formed with an ice-block mold, a refrigerant conduit extending into heat transfer- |04 represents a lid or cover for the waterv said circuit to pass at least a part of the refrigerant through said conduit, means for interrupting the flow of refrigerant through the conduit, time controlled means for intermittently actuating said interrupting means at relatively low frequency such that each interval between interruptions will include a plurality of operating periods of said intermittent cycle, meansv adapted to lead a current of air from the outside atmosphere in contact with said mold, and a controller for said air currents.

2. In an ice-making apparatus including a cooling circuit, and a refrigerating system for circulating refrigerant in said cooling circuit, said apparatus comprising a water tank provided with an ice block mold in heat transferring relation to said cooling circuit, a thermostatic member responsive to changes in temperatures of a part of said ice block mold, means actuated by said thermostatic member for starting and stopping said rei'rigerating system, and means for supplying heat to said mold and which are actuated by said thermostatic member when the operation of said refrigerating system is interrupted.

3. In an ice-making apparatus including an electrically driven refrigerating system for circulating refrigerant in a cooling circuit,.the combination of a water tank provided with an ice block mold in heat transferring relation to said cooling circuit, a thermostatic member responsive to changes in temperature of a part of said ice block mold, electrically operated means for supplying heat to said mold to release an ice block formed thereon, and electric control means actuated by said thermostatic member for simultaneously interrupting the supply of electricity to said electrically driven refrigerating system and to supply electric current to said electrically operated heat supplying means to release by meltage an ice block formed onsaid mold.

4. In an ice-making apparatus including an electrically driven refrigerating system for circulating refrigerant in a cooling circuit, the combination of a water tank provided with an ice block mold in heat transferring relation to said cooling circuit, a thermostatic member responsive to changes in temperature of a part of said ice block mold, an air chamber into which at least a portion of said mold extends, a blower for directing a current of air through said air space, an electric motor for driving said blower, and electric control means operated by said thermostatic member for simultaneously interrupting the supply of electricity to said electrically driven refrigerating system and for supplying electricity to said electric motor for driving said blower, to release by meltage an ice block formed on said mold.

THOMAS I. POTTER.