US3769809A

US3769809A - Control apparatus for an ice maker

Info

Publication number: US3769809A
Application number: US00145130A
Authority: US
Inventors: J Robinson; J Lyman
Original assignee: Whirlpool Corp
Current assignee: King Seeley Thermos Co
Priority date: 1971-05-20
Filing date: 1971-05-20
Publication date: 1973-11-06
Anticipated expiration: 1990-11-06
Also published as: CA962077A

Abstract

An ice maker of the type comprising a freezing cylinder with the coils of an evaporator disposed circumjacent thereto, an auger rotatable within the freezing cylinder and a bin for receiving and storing an ice product produced by the ice maker has a control apparatus adapted to control the operation of an auger motor rotating the auger so that the auger motor operates whenever the accumulation of ice within the storage bin is below a preselected level and the temperature of a compressor suction line connected to the evaporator is above a first preselected value and discontinuing the operation of the auger motor whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line at a point adjacent to a compressor is below a second preselected value less than the first preselected value. In that manner, the production of ice is regulated in accordance with the demand for ice and is discontinued in the event of excessive flood back to the compressor. The control apparatus also discontinues operation of the compressor in the event the auger motor becomes overloaded, and a clean cycle switch enables operation of the auger motor without simultaneously operating the compressor to facilitate cleaning operations.

Description

mired States Patent [1 1 obinson et al.

[ Nov. 6, 1973 CUNTROL APPARATUS FOR AN lCE MAKER [75] Inventors: James M. Robinson, White Bear Lake; John B. Lyman, Bloomington, both of Minn.

[73] Assignee: Whirlpool Corporation, Benton Harbor, Mich.

[22] Filed: May 20, 1971 [21] Appl. No.: 145,130

2,737,024 3/1956 Swenson 62/342 X Primary Examiner-William E. Wayner AtzorneyHill, Sherman, Meroni, Gross & Simpson [57] ABSTRACT An ice maker of the type comprising a freezing cylinder with the coils of an evaporator disposed circumjacent thereto, an auger rotatable within the freezing cylinder and a bin for receiving and storing an ice product produced by the ice maker has a control apparatus adapted to control the operation of an auger motor rotating the auger so that the auger motor operates whenever the accumulation of ice within the storage bin is below a preselected level and the temperature of a compressor suction line connected to the evaporator is above a first preselected value and discontinuing the operation of the auger motor whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line at a point adjacent to a compressor is below a second preselected value less than the first preselected value. in that manner, the production of ice is regulated in accordance with the demand for ice and is discontinued in the event of excessive flood back to the compressor. The control apparatus also discontinues operation of the compressor in the event the auger motor becomes overloaded, and a clean cycle switch enables operation of the auger motor without simultaneously operating the compressor to facilitate cleaning operations.

13 Claims, 1 Drawing Figure l l l Patentd Nov. 6, 1973 3,769,809

@WTTORNEYS CONTROL APPARATUS FOR AN ICE MAKER BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to an augertype ice making apparatus, and more particularly refers to a control circuit for controlling the operation of an auger-type ice maker in response to demand for ice and in a manner to prevent damage to the appartus.

While the present invention is described in reference to a specific auger-type ice maker including separate harvest and compression augers and being described in several copending applications commonly assigned with this application, the principles of the present invention have general utility with most auger-type ice machines.

2. Description of the Prior Art An auger-type ice maker generally comprises a freezing chamber having an interior cylindrical wall for cooperation with the flights of an auger rotatable within the chamber in a manner to harvest a film of ice which forms on the interior wall. The coils or passageway means of an evaporator are circumjacently disposed about the freezing chamber and form part of a refrigeration system, which also includes a compressor, a condenser, an expansion valve and conduits interconnecting the components and including a suction line between the evaporator and the compressor. An ice product produced by the ice maker may be tranported to and stored in an appropriate storage bin for utilization by a consumer.

In order to prevent damage to an auger motor driving the rotatable auger, it is desirable to prevent start up of the motor in the event the freezing chamber is clogged with accumulated ice. Further, an accumulation of ice within the freezing chamber during operation of the ice maker may overload the auger motor, in which event the operation of the auger motor is discontinued. To faciltate thawing of the ice maker unit so that the production of ice may be resumed, it is desirable to discontinue the operation of the compressor and the condenser fan whenever the auger motor cuts out due to an overload.

Heretofore, ice makers have been adapted to operate in response to demand for be within a storage bin, however, those ice makers have not included controls for preventing operation of the machine whenever the inlet water supply is interrupted, during a spin out condition when the system is full of ice but no new ice is being properly transferred fromthe freezing chamber or in the event of excessively low temperature operating conditions.

Also, in order to facilitatethe cleaning of the freezing chamber, it is desirable to operate the auger motor without simultaneously operating the compressor motor, thereby to agitate a cleaning fluid, such as an citric acid solution, within the freezing chamber.

SUMMARY OF THE INVENTION In accordance with the principles of the present invention, an auger-type ice maker comprising a freezing cylinder having means forming passageways of an evaporator disposed circumjacent thereto, with the evaporator being part of a refrigeration circuit which also includes a condenser and a compressor driven by an electric compressor motor and having a suction line connected to the evaporator, an auger rotatable within the freezing cylinder and being driven by an electric motor, a bin for receiving and storing an ice product produced by the ice maker, has a control apparatus adapted to operate the auger motor whenever there is a demand for ice within the bin and the temperature of the compressor suction line is above a first preselected value and discontinuing the operation of the auger motor whenever either the bin is full or the temperature of the compressor suction line is below a second preselected value less than that of the first preselected value. Thus, the ice maker isnot operated to produce ice in the event frost accumulates on the compressor suction line in an area adjacent the compressor, which condition will result from an excessive flood back of the refrigerant to the compressor. The excessive flood back may be due to a lack of inlet water being supplied to the freezing chamber, a spin out condition wherein the system is full of ice but no new ice is being properly transferred from the freezing chamber or an excessively low temperature operating condition.

Accordingly, when one of the conditions exist to cause excessive flood back to the compressor, the control means will sense that condition anddiscontinue the operation of the ice maker even thoughthe level'of accumulated ice within the bin is calling for the production of ice;

In order to prevent the unit from trying to start when the freezing chamber is full of ice or in an excessively cold ambient atmosphere, the control apparatus has a safety thermostatic switch preventing operation of the auger motor and the compressor motor whenever the temperature of the evaporator adjacent an outlet end of the freezing chamber is below a preselected value, for example 4l F. In the event the auger motor becomes overloaded during operation, a thermal overload switch will be actuated to interrupt the operation of the auger moton. t

The control apparatus also includes switch means connected with the auger motor, the compressor motor and the thermal overload switch and adapted to simultaneously operate the auger motor and the compressor motor and to discontinue the operation of the compressor motor in the event the overload switch stops the auger motor due to an overloaded condition. Thus, the compressor, and a condenser fan, which is controlled simultaneously with the compressor, are stopped when the auger becomes overloaded during operation due to an excessive accumulation of ice within the freezing chamber, thereby to facilitate the thawing of the machine... The safety thermostatic switch prevents restarting of the ice machine until the evaporator temperature has risen above the preselected value to indicate that the accumulated ice is thawed.

Occasionally it is necessary to clean the auger, the freezing chamber and other components through which the inlet water and ice pass, by circulating a cleaning solution, such as a citric acid, solution through the machine. Manually operable switch means in the control apparatus enable operation of the auger without simultaneously operating the refrigeration circuit, thereby enabling agitation of the cleaning solution during the cleaning operation.

BRIEF DESCRIPTION OF TI-lE DRAWING The drawing is a schematic illustration showing an auger-type ice maker for processing inlet water into a desired ice product deposited in a bin, a refrigeration circuit for the ice maker and a control apparatus embodying the principles of the present invention for controlling the operation of the ice maker.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT Referring to the drawing, an auger-type ice maker, generally indicated at 10, includes an evaporator unit 11 having a freezing chamber formed with an internal bore having a cylindrical wall 12. The evaporator unit 11 has an integrally formed evaporator passageway 13 into which a refrigerant or coolant is expanded by a refrigeration system, generally indicated at 14.

The refrigerant or coolant is expanded into the evaporator passageway 13 through an expansion valve 16, and a compressor 17 is in communication with the evaporator passageway via a suction line 18. The refrigeration system also comprises a condenser 19 serially connected between the compressor 17 and the expansion valve 16. An electric fan 21 circulates air through the condenser 19 to enhance the efficiency of the operation of the refrigeration system.

lnlet water for the production of ice is introduced into the evaporator unit 11 internally of the cylindrical wall 12 through an inlet conduit 22 disposed near a base of the unit 1 1. The water tends to freeze on the refrigerated wall 12 in the form of a thin film of ice. One or more helical flights 23 formed or carried on a rotating harvesting auger 24 cooperate with the cylindrical wall, which, in effect forms a freezing and scraping surface, whereby thin films of ice formed on that surface will be continuously harvested. The auger 24 progressively advances a mixture of ice particles, including slush and chunks, upwardly of the unit 11 towards a collection chamber 26 disposed superjacent of the evaporator unit 11.

In order to produce a clear ice product, the inlet water may be supplied in excess of an amount required for the production of ice. In that manner, minerals and other impurities will migrate or be frozen out of the thin film of ice and entrained in the liquid or unfrozen portion of the inlet water. The excess amount of inlet water, including the minerals and other impurities, is then discarded or drained from the unit via the drain outlet 27 opening above the collection chamber 26.

In order to compress the flake ice product harvested from the refrigerated scraping surface into a solid ice product, a compression auger 28 mounted for corotation with the harvesting auger 24 receives the flake ice product from the collection chamber 26 and squeezes the ice particles through a nozzle bore 29 to remove excess water and to form an emergent solid column of ice at an upper end 31 of the nozzle bore. An appropriately configured forming device may be secured at the upper end 31 of the nozzle bore for forming the emerging, solid column of hard ice into a desired configuration. As illustrated in the drawings, the forming device includes an elbow 32 for urging the emerging column transversely of the nozzle bore in a manner to break the column of hard ice into cubes or sections. Other forms of ice products may be produced by working the emerging column of hard ice, for example, the column may be worked to form chipped ice, shaved ice, cracked ice or small ice cubes.

The ice cubes formed as the emerging hard column of ice passes through the elbow 32 are delivered to an appropriate storage bin 33 via a conduit 34 extending from an outer end 36 of the elbow to the bin.

Suitable fastening means, such as bolts 37, secure the evaporator unit 11 to a drive housing 38. A shaft 39 disposed centrally of the evaporator unit 11 has a lower end portion supported within appropriate bearing means in the drive housing 38 and drivingly engaged by gear reduction means. Water is prevented from entering the drive housing 38 by appropriate seal means including a shaft seal 41 engaging the auger shaft 39.

In accordance with the principles of the present invention, the operation of an auger drive motor 42, a compressor motor 43 and a fan motor 44 is controlled by a control apparatus in a manner to produce ice in reponse to a demand for ice in the storage bin 33 and in a manner to prevent damage to the ice maker 10 and its various components.

The control apparatus includes control circuit means for controlling the operation of the auger motor 42 so that the auger motor is operated whenever the accum ulation of ice within the bin 33 is below a preselected level and the temperature of the compressor suction line 18 at a location adjacent to the compressor 17 is above a first preselected value and the operation of the auger motor is discontinued whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line is below a second preselected value less than the first preselected value. Thus, the ice maker is operated in response to the level of ice within the storage bin and in response to the temperature of the suction line 18. In the event there is an excessive flood back of the refrigerant or coolant to the compressor 17, frost will accumulate on the compressor suction line in the area adjacent the compressor. That excessive flood back may be due to .any number of reasons, including a lack of inlet water being supplied to the freezing chamber via the inlet conduit 22, a spin outcondition wherein the system is full of ice but no new ice is being properly transferred from the freezing chamber or an excessively low temperature operating condition.

As illustrated in the drawing, the control circuit means comprises a series circuit including at least an input terminal 46 for connection with an electric supply, the auger motor 42 and a thermostatic control switch 47 having contacts positioned in response to a sensed temperature by bellows means 48. The thermostatic control switch 47 has a temperature sensing bulb element 49 disposed within the bin 33 and positioned to sense the temperature of the bin in a manner to indicate the level of ice accumulated therewithin. A capillary tube 51 innerconnects the bulb element 49 to the positioning bellows 48 and has a portion 51a passing adjacent to or wrapped around the suction line 18 in an area adjacent tothe compressor 17. The thermostatic switch 47 is.of the type which operates in response to the coldest temperature sensed, and thus, if either the suction line temperature falls below the setting of the switch or the bin becomes sufficiently full to lower the bin temperature below the setting of the switch, the normally closed contacts of the switch will open to discontinue operation of the auger motor, thereby stopping the production of ice. By utilizing the capillary tube 51 to sense the condition of the compressor suction line 18, the present invention provides a low cost shut off device for the auger motor 42 and the compressor 43. In a commercial example of the ice maker 10, the contacts of the control switch 47 are closed at sensed temperatures above 41F. and are opened when the sensed temperature drops below 35F.

in order to prevent the unit from trying to start when the evaporator 11 is clogged with ice or when the unit is in an excessively cold ambient atmosphere, the control apparatus of the present invention inlcudes a safety thermostatic switch 52 preventing operation of the auger motor 42, and thus the compressor motor, whenever the temperature of the evaporator adjacent an outlet end of the freezing chamber is below a preselected value, for example 41F. The safety thermostatic switch means is connected in the control circuit in series between the control thermostatic switch 48 and a thermal overload switch 53 for the auger motor 42. The thermostatic safety switch 52 has contacts positioned by an appropriate bellow means or the like as at 54, with the bellow means being operated by a remote sensing bulb element 56. The sensing bulb element 56 is partially wrapped around an exterior of the evapora tor unit 11 immediately subjacent the collection cham-.

ber 26 or adjacent an outlet end of the freezing chamber. Thus, a drop in the temperature of the evaporator unit 11 due to an excessive accumulation of ice within the freezing chamber will be detected by the bulb element 56. in a commercial example of the present invention, the contacts of the safety thermostatic switch are closed at temperatures above approximately 41F. and are opened below temperatures of about 35F, in a manner similar to that of the controlled thermostatic switch 47.

lt is also contemplated by the present invention to provide switch means connected with the input terminal block 46, the auger motor 42, the auger motor thermal overload switch 53 and the compressor motor 43 with the switch means being adapted to simultaneously operate the auger motor and the compressor motor and to discontinue the operation of the compressor motor whenever the operation of the auger motor is discontinued due to the normally closed contacts of the thermal overload switch opening or otherwise. That switch means generally include a manually operable, double pole, double throw switch 57 and relayswitch means 58 having a relay coil 59 controlling the condition of a first set of normally opened contacts 61 and a second set of normally opened contacts 62. The manually operable switch 57 is the primary control switch for the ice maker unit and has a first set of contacts indicated at 63 and a second set of contacts indicated at 64, both of which are normally closed when the switch 57 is positioned in the normal running condition. The first set of normally closed contacts 63 are connected in a series circuit comprising the control thermostatic switch 47, the safety thermostatic switch 53, the thermal overload switch 53 and the auger motor 42, thereby operating the auger motor whenever the'contacts of the control thermostat and the safety thermostat are closed.

A lead 66 connected as at 67 between the thermal overload switch 53 and the auger motor42 extends to the second set of normally closed contacts 64 of the main control switch, and that set of contacts is connected in series with the relay coil 59. Further, the series circuit including the normally closed contacts 64 and the relay coil 59 are connected in parallel with the auger motor 42. Thus, when the main control switch 57 is in the running condition, as illustrated in the drawings, the relay coil is energized, thereby closing the two sets of

contacts

61 and 62.

In order to avoid passing the start up current for the compressor unit 43 through the main control switch 47, and thus enabling the use of a switch having a lower rating, the second set of contacts 62 of the relay switch 58 are connected with the compressor motor 43 to control the operation of the same. Also, the fan motor 44 is connected in parallel with the compressor motor 43 to operate inunison therewith.

Since the relay coil 59 is disposed in parallel with the auger motor 42, the relay coil will be deenergized whenever the operation of the auguer motor is discontinued due to opening of the thermal overload switch 53 or, the control switch 47.

The second set of normally closed contacts of the relay switch 58 are connected in parallel with the safety thermostatic switch 52, thereby providing a circuit bypassing the safety thermostatic switch once the unit has been started. That bypass circuit opens whenever the auger motor 42 stops, thereby requiring the contacts of the safety thermostatic switch to be closed before the auger motor will restart. For example, when the auger motor 42 becomes overloaded causing the thermal overload switch 53 to open, the relay coil will be deenergized to open the first setof relay contacts 61 so that the auger motor may not be restarted under a loaded condition due to, for example, the evaporator unit 11 being clogged with excessive ice.

During use, scale may accumulate on the walls of the freezing chamber, the harvest auger 24 and the compression auger 28. The accumulated scale may be cleaned by circulating an appropriate cleaning solution, such as a citric acid solution, through the machine. To enhance the cleaning operation, it is desirable to agitate the cleaning solution, and thus, the control apparatus includes switch means for a cleaning cycle wherein only the auger motor 42 is operated without the compressor motor 43 and the fan motor 44 being operated. Accordingly, the manually operable, main control switch 57 includes'a contact 68 which is normally opened when the switch is positioned in the running condition and which closes when the switch is positioned in a clean cycle condition. The normally opened contacts 68 is connected in parallel with a series circuit comprising the normally closed contacts 63 I of the switch 57, the control thermostatic switch 47 and the safety thermostatic switch 52, thereby bypassing the safety thermostat and the control thermostat to operate the auger motor 42. Since the normally closed contacts 64 in series with the relay coil 59 are opened during the clean cycle, the compressor motor 43 and the fan motor 44 are not operated.

Although those versed in the art may suggest various minor modifications, it should be understood that we wish to embodywithin the scope of the patent warranted hereon, all such modifications as reasonably and properly come within the scope of our contribution to the art.

We claim as our invention:

1. In an ice maker of the type comprising a freezing cylinder having means forming passageways of an evaporator disposed circumjacent thereto, the evaporator being part of a refrigeration circuit which also includes a condenser and a compressor driven by an electric compressor motor and having a suction line connected with the evaporator, an auger rotatable within the freezing cylinder and being driven by an electric auger motor, bin means for receiving and storing an ice product produced by the ice maker, and control circuit means controlling the operation of the ice maker, the improvement wherein said control circuit comprises:

input terminals for connection with an electric supply; bin sensing means for sensing the level of ice in said bin; suction line sensing means for sensing the temperature of the compressor suction line; control circuit means for controlling the operation of said auger motor and being connected with said input terminals, said circuit means including a single single-pole switch operated by said bin sensing means and said suction line sensing means for operating said auger motor whenever the accumu-lation of ice within the bin is below a preselected level and the temperature of the compressor suction line adjacent to the compressor is above a first preselected value and discontinuing the operation of the auger motor whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below a second preselected value less than the first preselected value.

2. In an ice maker, a control circuit as defined in claim 1 and further characterized by:

said control circuit means comprising a series circuit connected with said input terminals and including the auger motor and said switch, said switch closing whenever the accumulation of ice within the bin is below the preselected level and the temperature of the compressor suction line adjacent to the compressor is above the first preselected value and opening whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below the second preselected value.

3. In an ice maker, a control circuit as defined in claim 2, said series circuit further comprising a normally closed thermal overload switch connected in series with the auger motor and opening whenever the auger motor is overloaded.

4. In an ice maker of the type comprising a freezing cylinderhaving means forming passageways and an evaporator disposed circumjacent thereto, the evaporator being part of a refrigeration circuit which also includes a condenser and a compressor driven by an electric compressor motor and having a suction line connected with the evaporator, an auger rotatable within the freezing cylinder and being driven by an electric auger motor, bin means for receiving and storing an ice product produced by the ice maker, and control circuit means controlling the operation of the ice maker, the improvement wherein said control circuit comprises:

input terminals for connection with an electric supply; bin sensing means for sensing the level of ice in said bin; suction line sensing means for sensing the temperature of the compressor suction line; control circuit means for controlling the operation of said auger motor and being connected with said input terminals, said circuit means operating said auger motor whenever the accumulation of ice within the bin is below a preselected level and the temperature of the compressor suction line adjacent to the compressor is above a first preselected value and discontinuing the operation of the auger motor whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below a second preselected value less than the first preselected value,

said control circuit means comprising a series circuit connected with said input terminals and including the auger motor and control switch means operated by said bin sensing means and said suction line sensing means for closing whenever the accumulation of ice within the bin is below the preselected level and the temperature of the compressor suction line adjacent to the compressor is above the first preselected value and opening whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below the second preselected value,

said series circuit further comprising av noramally closed thermal overload switch connected in series with the auger motor and opening whenever the auger motor is overloaded,

thermostatic safety switch means sensing the temperature of the evaporator and closing whenever the temperature of the evaporator is above a first preselected value and opening whenever the temperature of the evaporator isbelow a second preselected value less than said first preselected value, and

relay switch means including a relay coil and a first set of normally opened contacts, 'said relay coil being connected in parallel with said auger motor, a

and said first set of normally opened contacts being connected in parallel with said safety switch means, whereby whenever said thermal overload switch opens, said first set of relay contacts opens so that said auger motor means may not be restarted unless said safety thermostatic switch means are closed.

5. In an ice maker, a control circuit as defined in claim 4, and further characterized by:

said relay switch means including a second set of normally opened contacts connected with the compressor motor and closing to operate the compressor motor whenever said relay coil is energized and opening whenever said relay coil is deenergized, whereby said compressor will not be operated in the event said thermal overload switch is opened.

6. In an ice maker, a control circuit as defined in claim 5 and further comprising:

manually operable switch means having a first set of normally closed contacts, a second set of normally closed contacts and a set or normally opened contacts, all of said sets of contacts being mechanically innerconnected for operation in unison, said first set of normally closed contacts being connected in a series circuit comprising said control switch means, said thermostatic safety swtich means, said auger motor overload switch means and the auger motor, said second set of normally closed contacts being connected in series with said relay coil, and said set of normally opened contacts being connected in parallel with said control switch means, said safety thermostatic switch means, and said first set of normally closed contacts. 7. An apparatus for controlling the operation of an ice maker of the type having means forming passageways of an evaporator disposed circumjacent thereto, the evaporator being part of a refrigeration circuit which also includes a condenser and a compressor having a suction line connected with the evaporator, an auger rotatable within the freezing cylinder and bin means for receiving and storing an ice product produced by the ice maker, the control apparatus comprismg:

input terminal means for connection with an electric pp y a an electric motor for rotating the auger and including a thermal overload switch for interrputing the operation of the auger motorwhen the same becomes overloaded;

an electric compressor motor for operating the compressor; and

control means connected with said input terminal means, said auger motor, said thermal overload switch and said compressor motor and including switch means simultaneously operating said auger motor and said compressor motor and discontinuing the operation of said compressor motor whenever said overload switch opens tointerrupt the operation of said auger motor.

8. A control apparatus as defined in claim 7 wherein said switch means comprises:

relay switch means including a relay coil and a set of normally opened contacts, said relay coil being connected in parallel with said auger motor and said set of relay contacts being connected in series with said compressor motor, whereby whenever said thermal overload switch opens, said relay coil is deenergized to open said set of relay contacts to discontinue the operation of said compressor motor.

9. A control apparatus as defined in claim 8, wherein said switch means further comprises:

manually operable switch means having a first set of normally closed contacts, a second set of normally closed contacts and a set of normally opened contacts, all of said sets of contacts being mechanically innerconnected for operation in unison,

said first set of normally closed contacts being connected in a series circuit comprisingsaid auger motor and said thermal overload switch,

said second set of normally closed contacts being connected in series with said relay coil, and

said set of normally opened contacts being connected in parallel with said first set of normally closed contacts, whereby whenever said set of normally opened contacts are closed, said relay coil is deenergized to prevent the operation of said compressor motor, while enabling the operation of said auger motor'separately of said compressor motor.

10. In an ice maker of the type comprising a freezing cylinder having means forming passageways and an evaporator disposed circumjacent thereto, the evaporator being part of a refrigeration circuit which also includes a condenser and a compressor driven by an electric compressor motor and having a suction line connected with the evaporator, an auger rotatable within the freezing cylinder and being driven by an electric auger motor, bin means for receivingand storing an ice product produced by the ice maker, and control circuit means controlling the operation of the ice maker, the improvement wherein said control circuit comprises:

input terminals for connection with an electric supply; bin sensing means for sensing the level of ice in said bin;

suction line sensing means for sensing the temperature of the compressor suction line;

control circuit means for controlling the operation of said auger motor and being connected with said input terminals, said circuit means operating said auger motor whenever the accumulation of ice within the bin is below a preselected level and the temperature of the compressor suction line adjacent to the compressor is above a first preselected value and discontinuing the operation of the auger motor whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below a second preselected value less than the first preselected value,

said control circuit means comprising a series circuit connected with said input terminals and including the auger motor, and control switch means comprising a single single-pole switch operated by said bin sensing means and said suction line sensing means for closing whenever the accumulation of ice within the bin is below the preselected level and the temperature of the compressor suction line adjacent to the compressor is above the first preselected value and the temperature of the evatorator is above a preselected temperature.

11. In an ice maker of the type comprising a freezing cylinder having means forming passageways and an evaporator disposed circumjacent thereto, the evaporator being part of a refrigeration circuit which also includes a condenser and a compressor driven by an electric compressor motor and having a suction line connected with the evaporator, an auger rotatable within the freezing cylinder and being driven by an electric auger motor, bin means for receiving and storing an ice product produced by the ice maker, and control circuit means controlling the operation of the ice maker, the improvement wherein said control circuit comprises:

input terminals for connection with an electric supply; bin sensing means for sensing the level of ice in said bin; suction line sensing means for sensing the temperature of the compressor suction line;

control circuit means for controlling the operation of a said auger motor and being connected with said input terminals and circuit means operating said auger motor whenever the accumulation of ice within the bin is below a preselected level and the temperature of the compressor suction line adjacent to the compressor is above a first preselected value and discontinuing the operation of the auger motor whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below a second preselected value less than the first preselected value, said control circuit means comprising a series circuit connected with said input terminals and including the auger motor and control switch means operated by said bin sensing means and said suction line sensing means for closing whenever the accumulation of ice within the bin is below the preselected level and the temperature of the compessor suction line adjacent to the compressor is above the first preselected value and opening whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below the second preselected value, and

relay switch means including a relay coil and a first set of normally opened contacts, said relay coil being connected in parallel with said auger motor, and said first set of normally opened contacts being connected between said compressor motor and said input terminals.

12. In an ice maker of the type comprising a freezing cylinder having means forming passageways and an evaporator disposed circumjacent thereto, the evaporator being part of a refrigeration circuit which also includes a condenser and a compressor driven by an electric compressor motor and having a suction line connected with the evaporator, an auger rotatable within the freezing cylinder and being driven by an electric auger motor, bin means for receiving and storing an ice product produced by the ice maker, and control circuit means controlling the operation of the ice maker, the improvement wherein sqid control circuit comprises:

input terminals for connection with an electric sup- P y; control circuit means for controlling the operation of said auger motor and being connected with said input terminals, said circuit means operating said auger motor whenever the accumulation of ice within the bin is below a preselected level and the temperature of the compressor suction line adjacent to the compressor is above a first preselected value and discontinuing the operation of the auger motor whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below a second preselected value less than the first preselected value, said control circuit means comprising a series circuit. connected with said input terminals and including the auger motor and control switch means closing whenever the accumulation of ice within the bin is below the preselected level and the temperature of the compressor suction line adjacent to the compressor is above the first preselected value and opening whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below the second presewherein said capillary tube has a portion disposed adjacent to and sensing the temperature of the compressor suction line at a location adjacent the compressor. 13. In an ice maker of the type comprising a freezing cylinder having means forming passageways of an evaporator disposed circumjacent thereto, the evaporator being part of a refrigeration circuit which also includes a condenser and a compressor driven by an electric compressor motor and having a suction line connected with the evaporator, an auger rotatable within the freezing cylinder and being driven by an electric auger motor, bin means for receiving and storing an ice product produced by the ice maker, and control circuit means controlling the operation of the ice maker, the improvement wherein said control circuit comprises:

input terminals for connection with an electric supcontrol circuit means for controlling the operation of said auger motor and being connected with said input terminals, said circuit means including a single switch for operating said auger motor whenever the accumulation of ice within the bin is below a preselected level and the temperature of the compressor is above a first preselected value and discontinuing the operation of the auger motor whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below a second preselected value less than the first preselected value;

said control circuit means comprising a series circuit connected with said input terminals and including the auger motor and said switch, said switch closing whenever the accumulation of ice within the bin is below the preselected level and the temperature of the compressor suction line adjacent to the compressor is above the first preselected value and opening whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below the second preselected value;

said switch comprising a thermostatic switch having a temperature sensing bulb element disposed in the bin and a capillary tube innerconnecting said bulb element with means controlling the condition of said control switch means, wherein said capillary tube has a portion disposed adjacent to and sensing the temperature of the compressor suction line at a location adjacent the compressor.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION 3,769,809 Dated siovcmner 6,, 1973 Patent No.

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column line 15, "accumu-lation" should read accumulation Col 11, line 22, "sqid" should read said Signed and sealed this 21st day of May 1971;.

(SEAL) Attest:

EJDZJAEQJ Z-LFLETGE-TER, JR. C. MARSHALL DANE G mmissioneroi Patents Attesting Officer-

Claims

1. In an ice maker of the type comprising a freezing cylinder having means forming passageways of an evaporator disposed circumjacent thereto, the evaporator being part of a refrigeration circuit which also includes a condenser and a compressor driven by an electric compressor motor and having a suction line connected with the evaporator, an auger rotatable within the freezing cylinder and being driven by an electric auger motor, bin means for receiving and storing an ice product produced by the ice maker, and control circuit means controlling the operation of the ice maker, the improvement wherein said control circuit comprises: input terminals for connection with an electric supply; bin sensing means for sensing the level of ice in said bin; suction line sensing means for sensing the temperature of the compressor suction line; control circuit means for controlling the operation of said auger motor and being connected with said input terminals, said circuit means including a single single-pole switch operated by said bin sensing means and said suction line sensing means for operating said auger motor whenever the accumu-lation of ice within the bin is below a preselected level and the temperature of the compressor suction line adjacent to the compressor is above a first preselected value and discontinuing the operation of the auger motor whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below a second preselected value less than the first preselected value.

2. In an ice maker, a control circuit as defined in claim 1 and further characterized by: said control circuit means comprising a series circuit connected with said input terminals and including the auger motor and said switch, said switch closing whenever the accumulation of ice within the bin is below the preselected level and the temperature of the compressor suction line adjacent to the compressor is above the first preselected value and opening whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below the second preselected value.

4. In an ice maker of the type comprising a freezing cylinder having means forming passageways and an evaporator disposed circumjacent thereto, the evaporator being part of a refrigeration circuit which also includes a condenser and a compressor driven by an electric compressor motor and having a suction line connected with the evaporator, an auger rotatable within the freezing cylinder and being driven by an electric auger motor, bin means for receiving and storing an ice product produced by the ice maker, and control circuit means controlling the operation of the ice maker, the improvement wherein said control circuit comprises: input terminals for connection with an electric supply; bin sensing means for sensing the level of ice in said bin; suction line sensing means for sensing the temperature of the compressor suction line; control circuit means for controlling the operation of said auger motor and being connected with said input terminals, said circuit means operating said auger motor whenever the accumulation of ice within the bin is below a preselected level and the temperature of the compressor suction line adjacent to the compressor is above a first preselected value and discontinuing the operation of the auger motor whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below a second preselected value less than the first preselected value, said control circuit means comprising a series circuit connected with said input terminals and including the auger motor and control switch means operated by said bin sensing means and said suction line sensing means for closing whenever the accumulation of ice within the bin is below the preselected level and the temperature of the compressor suction line adjacent to the compressor is above the first preselected value and opening whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below the second preselected value, said series circuit further comprising a noramally closed thermal overload switch connected in series with the auger motor and opening whenever the auger motor is overloaded, thermostatic safety switch means sensing the temperature of the evaporator and closing whenever the temperature of the evaporator is above a first preselected value and opening whenever the temperature of the evaporator is below a second preselected value less than said first preselected value, and relay switch means including a relay coil and a first set of normally opened contacts, said relay coil being connected in parallel with said auger motor, and said first set of normally opened contacts being connected in parallel with said safety switch means, whereby whenever said thermal overload switch opens, said first set of relay contacts opens so that said auger motor means may not be restarted unless said safety thermostatic switch means are closed.

5. In an ice maker, a control circuit as defined in claim 4, and further characterized by: said relay switch means including a second set of normally opened contacts connected with the compressor motor and closing to operate the compressor motor whenever said relay coil is energized and opening whenever said relay coil is deenergized, whereby said compressor will not be operated in the event said thermal overload switch is opened.

6. In an ice maker, a control circuit as defined in claim 5 and further compRising: manually operable switch means having a first set of normally closed contacts, a second set of normally closed contacts and a set or normally opened contacts, all of said sets of contacts being mechanically innerconnected for operation in unison, said first set of normally closed contacts being connected in a series circuit comprising said control switch means, said thermostatic safety swtich means, said auger motor overload switch means and the auger motor, said second set of normally closed contacts being connected in series with said relay coil, and said set of normally opened contacts being connected in parallel with said control switch means, said safety thermostatic switch means, and said first set of normally closed contacts.

7. An apparatus for controlling the operation of an ice maker of the type having means forming passageways of an evaporator disposed circumjacent thereto, the evaporator being part of a refrigeration circuit which also includes a condenser and a compressor having a suction line connected with the evaporator, an auger rotatable within the freezing cylinder and bin means for receiving and storing an ice product produced by the ice maker, the control apparatus comprising: input terminal means for connection with an electric supply; an electric motor for rotating the auger and including a thermal overload switch for interrputing the operation of the auger motor when the same becomes overloaded; an electric compressor motor for operating the compressor; and control means connected with said input terminal means, said auger motor, said thermal overload switch and said compressor motor and including switch means simultaneously operating said auger motor and said compressor motor and discontinuing the operation of said compressor motor whenever said overload switch opens to interrupt the operation of said auger motor.

8. A control apparatus as defined in claim 7 wherein said switch means comprises: relay switch means including a relay coil and a set of normally opened contacts, said relay coil being connected in parallel with said auger motor and said set of relay contacts being connected in series with said compressor motor, whereby whenever said thermal overload switch opens, said relay coil is deenergized to open said set of relay contacts to discontinue the operation of said compressor motor.

9. A control apparatus as defined in claim 8, wherein said switch means further comprises: manually operable switch means having a first set of normally closed contacts, a second set of normally closed contacts and a set of normally opened contacts, all of said sets of contacts being mechanically innerconnected for operation in unison, said first set of normally closed contacts being connected in a series circuit comprising said auger motor and said thermal overload switch, said second set of normally closed contacts being connected in series with said relay coil, and said set of normally opened contacts being connected in parallel with said first set of normally closed contacts, whereby whenever said set of normally opened contacts are closed, said relay coil is deenergized to prevent the operation of said compressor motor, while enabling the operation of said auger motor separately of said compressor motor.

10. In an ice maker of the type comprising a freezing cylinder having means forming passageways and an evaporator disposed circumjacent thereto, the evaporator being part of a refrigeration circuit which also includes a condenser and a compressor driven by an electric compressor motor and having a suction line connected with the evaporator, an auger rotatable within the freezing cylinder and being driven by an electric auger motor, bin means for receiving and storing an ice product produced by the ice maker, and control circuit means controlling the operation of the ice maker, the improvement wherein said control circuit comprises: input terminals for connection with an Electric supply; bin sensing means for sensing the level of ice in said bin; suction line sensing means for sensing the temperature of the compressor suction line; control circuit means for controlling the operation of said auger motor and being connected with said input terminals, said circuit means operating said auger motor whenever the accumulation of ice within the bin is below a preselected level and the temperature of the compressor suction line adjacent to the compressor is above a first preselected value and discontinuing the operation of the auger motor whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below a second preselected value less than the first preselected value, said control circuit means comprising a series circuit connected with said input terminals and including the auger motor, and control switch means comprising a single single-pole switch operated by said bin sensing means and said suction line sensing means for closing whenever the accumulation of ice within the bin is below the preselected level and the temperature of the compressor suction line adjacent to the compressor is above the first preselected value and the temperature of the evatorator is above a preselected temperature.

11. In an ice maker of the type comprising a freezing cylinder having means forming passageways and an evaporator disposed circumjacent thereto, the evaporator being part of a refrigeration circuit which also includes a condenser and a compressor driven by an electric compressor motor and having a suction line connected with the evaporator, an auger rotatable within the freezing cylinder and being driven by an electric auger motor, bin means for receiving and storing an ice product produced by the ice maker, and control circuit means controlling the operation of the ice maker, the improvement wherein said control circuit comprises: input terminals for connection with an electric supply; bin sensing means for sensing the level of ice in said bin; suction line sensing means for sensing the temperature of the compressor suction line; control circuit means for controlling the operation of said auger motor and being connected with said input terminals and circuit means operating said auger motor whenever the accumulation of ice within the bin is below a preselected level and the temperature of the compressor suction line adjacent to the compressor is above a first preselected value and discontinuing the operation of the auger motor whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below a second preselected value less than the first preselected value, said control circuit means comprising a series circuit connected with said input terminals and including the auger motor and control switch means operated by said bin sensing means and said suction line sensing means for closing whenever the accumulation of ice within the bin is below the preselected level and the temperature of the compessor suction line adjacent to the compressor is above the first preselected value and opening whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below the second preselected value, and relay switch means including a relay coil and a first set of normally opened contacts, said relay coil being connected in parallel with said auger motor, and said first set of normally opened contacts being connected between said compressor motor and said input terminals.

12. In an ice maker of the type comprising a freezing cylinder having means forming passageways and an evaporator disposed circumjacent thereto, the evaporator being part of a refrigeration circuit which also includes a condenser and a compressor driven by an electric compressor motor And having a suction line connected with the evaporator, an auger rotatable within the freezing cylinder and being driven by an electric auger motor, bin means for receiving and storing an ice product produced by the ice maker, and control circuit means controlling the operation of the ice maker, the improvement wherein sqid control circuit comprises: input terminals for connection with an electric supply; control circuit means for controlling the operation of said auger motor and being connected with said input terminals, said circuit means operating said auger motor whenever the accumulation of ice within the bin is below a preselected level and the temperature of the compressor suction line adjacent to the compressor is above a first preselected value and discontinuing the operation of the auger motor whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below a second preselected value less than the first preselected value, said control circuit means comprising a series circuit connected with said input terminals and including the auger motor and control switch means closing whenever the accumulation of ice within the bin is below the preselected level and the temperature of the compressor suction line adjacent to the compressor is above the first preselected value and opening whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below the second preselected value, and a thermostatic switch having a temperature sensing bulb element disposed in the bin and a capillary tube innerconnecting said bulb with means controlling the condition of said control switch means, wherein said capillary tube has a portion disposed adjacent to and sensing the temperature of the compressor suction line at a location adjacent the compressor.

13. In an ice maker of the type comprising a freezing cylinder having means forming passageways of an evaporator disposed circumjacent thereto, the evaporator being part of a refrigeration circuit which also includes a condenser and a compressor driven by an electric compressor motor and having a suction line connected with the evaporator, an auger rotatable within the freezing cylinder and being driven by an electric auger motor, bin means for receiving and storing an ice product produced by the ice maker, and control circuit means controlling the operation of the ice maker, the improvement wherein said control circuit comprises: input terminals for connection with an electric supply; control circuit means for controlling the operation of said auger motor and being connected with said input terminals, said circuit means including a single switch for operating said auger motor whenever the accumulation of ice within the bin is below a preselected level and the temperature of the compressor is above a first preselected value and discontinuing the operation of the auger motor whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below a second preselected value less than the first preselected value; said control circuit means comprising a series circuit connected with said input terminals and including the auger motor and said switch, said switch closing whenever the accumulation of ice within the bin is below the preselected level and the temperature of the compressor suction line adjacent to the compressor is above the first preselected value and opening whenever either the accumulation of ice within the bin is above the preselected level or the temperature of the compressor suction line adjacent to the compressor is below the second preselected value; said switch comprising a thermostatic switch having a temperature sensing bulb element disposed in the bin and a capillary tube innerconnecting said bulb element with means controlling the condition of said control switch means, wherein said capillary tube has a portion disposed adjacent to and sensing the temperature of the compressor suction line at a location adjacent the compressor.