US3511059A

US3511059A - Auger ice maker with freeze-up control

Info

Publication number: US3511059A
Application number: US716961A
Authority: US
Inventors: Walter H Hoenisch
Original assignee: King Seeley Thermos Co
Current assignee: King Seeley Thermos Co
Priority date: 1968-03-28
Filing date: 1968-03-28
Publication date: 1970-05-12
Anticipated expiration: 1987-05-12

Description

1 1 1 l/ 11 1 71, n1 /fl/ 1 /1 ,7 1/ 1 1/ 1/ I I 2 Sheets-Sheet 1 II I, 1/ 1 I/ ll 1 1/ 1 1 I '1 ///1 1 1/ 11 1/ 11 11 /1 11 11 1 w. H. HOENISCH AUGER ICE MAKER WITH FREEZE-UP CONTROL May 12, 1970 Filed March 28, 1968 l D I nu 0 1/ 11 11 1 1 1/ 11 1 1 11 11 1 1/ 1/ I h May 12, 1970 w. H. HOENISCH 3,511,059

AUGER ICE MAKER WITH FREEZE-UP CONTROL Filed March 28, 1968 2 Sheets-Sheet z FE. 4 MEMO? l ISM/1161' Hwy/fix,

flz amvzrfi United States Patent AUGER ICE MAKER WITH FREEZE-UP CONTROL Walter H. Hoenisch, Albert Lea, Minn., assignor to King- Seeley Thermos Co., Ann Arbor, Mich., a corporation of Michigan Filed Mar. 28, 1968, Ser. No. 716,961 Int. Cl. F25c 1/14 US. Cl. 62-138 7 Claims ABSTRACT OF THE DISCLOSURE An ice making machine including an ice forming chamber; a refrigeration system for producing ice within the chamber; a dispensing mechanism for transferring ice from the chamber to an associated storage bin or the like; a control system comprising an electrical circuit for selectively transmitting electrical power to the refrigeration system and the dispensing mechanism, and control means for selectively opening and closing the aforesaid circuit in response to preselected movement of the dispensing mechanism within the ice forming chamber, whereby the refrigeration system will be automatically deenergized in the event the dispensing mechanism tends to become frozen within the ice forming chamber, thus alleviating the freezing conditions Within the chamber until proper operation of the dispensing mechanism is resumed.

BACKGROUND OF THE INVENTION By virtue of the fact that ice in particulate form, such as shaved, pulverized, crushed or flaked ice, has the desirable characteristics of affording both rapid cooling and extreme portability, there has been an increasing demand for suitable equipment adapted to conveniently dispense and store ice in such particulate form. Although a wide variety of different types of equipment have heretofore been known and used for producing ice in particulate form, one type of apparatus that has been found to be highly successful consists of a generally cylindrical shaped ice forming chamber within which a helical or similar type auger is rotatably mounted. The chamber is provided with a source of water adapted to be frozen around the inner periphery of the chamber wall by means of an associated refrigeration system arranged in heat transfer relation with respect to the ice forming chamber. Upon energization of an associated drive motor, the auger rotates in a manner such that the ice formed within the chamber is conveyed axially outwardly therefrom to an associated storage bin or the like.

Although such auger-type flaked ice manufacturing and dispensing devices have been very effective in con veniently and accurately dispensing quantities of flaked ice in an extremely sanitary and spillage-free manner, such apparatus, under certain operating conditions, have been subject to a problem wherein the ice dispensing augers thereof would freeze within the ice forming chamber, with the result that the drive motors associated therewith would be unable to rotate the augers, thus rendering the apparatus temporarily inoperable. For example, after such a flaked ice dispensing machine has been operating for a period of time, wherein temperature of the water in the ice forming chamber thereof is approximately 32 F., when the machine is temporarily turned off, resulting in deactuation of the refrigerator compressor and anger, the refrigerant in the evaporator continues to provide or produce freezing conditions within the ice forming chamber for a certain period of time, thereby freezing the auger within the chamber. When the machine is subsequently turned on prior to the ice forming chamber having an opportunity to warm up, it has been the practice to have the refrigerator compressor energized immediately, thereby freezing the auger more solidly within the chamber, and with the further result that the Water which is thereafter communicated into the chamber freezing into a solid mass of ice having the auger embedded therein.

Another example of when the aforementioned type flaked ice producing machines have been found to have the ice dispensing augers thereof frozen within their associated ice forming chambers is when a restriction occurs in the water inlet line, resulting in the ice forming chamber becoming excessively cold. When this happens, the ice that forms around the inner periphery of the chamber is not totally removed by the ice dispensing auger, thereby causing slower rotation of the auger. This condition is further aggravated due to the fact that the refrigerator compressor remains energized, causing a greater build up of ice within the chamber, with the ultimate result that the interior of the chamber freezes solid. A similar result has been found to occur when the discharge spout between the ice forming chamber and the associated storage bin becomes restricted, resulting in flaked ice accumulating within the chamber and eventually freezing the auger solidly therewithin.

The present invention is intended to overcome the above described problems encountered with anger and similar type flaked ice dispensing machines through the provision of an ice producing and dispensing machine incorporating a novel control system adapted to selectively control energization of the various operational components of the machine. Generally speaking, the subject control system comprises an electrical control circuit operatively connecting the refrigeration system of the machine with a suitable source of electrical power as is commonly available, with the control circuit including means responsive to the rotational movement of the ice dispensing auger for selectively energizing the refrigeration system, thus assuring that in the event the anger is not rotating properly preparatory to or during an ice dispensing cycle, the refrigeration system will not be initially energized or will be deenergized so as to not aggravate any undesirable freezing conditions within the ice forming chamber. More particularly, the control circuit comprises a centrifugal or similar type actuating mechanism adapted to be mounted on the drive assembly of the ice dispensing auger, whereby rotation of the auger.

below a predetermined speed effects actuation of the mechanism. Disposed adjacent the centrifugal actuating mechanism is an electrical switching device adapted to selectively open and close an electrical circuit between the source of electrical power and the associated refrigeration system. During normal operation of the machine, the switch terminals are closed, with the result that the refrigeration system is energized to provide for the normal production of ice within the ice forming chamber; however, when the rotational speed of the auger drops below a predetermined level, the switching device will be actuated by the centrifugal mechanism, thereby opening the switch terminals and deenergizing the refrigerator system. At such time as the rotational speed of the auger reaches the aforesaid predetermined level, the centrifugal mechanism will permit the terminals of the switching device to close, thereby resuming normal operation of the associated refrigeration system.

With the above described construction, at such time as the ice producing machine is deenergized under conditions wherein the dispensing auger becomes temporarily frozen within the ice forming chamber, upon reenergization of the machine, the rotational speed of the auger will be below the aforementioned predetermined level, with the result that the terminals of the switching device will remain open and the refrigeration system deenergized. Under such frozen conditions, the auger will begin to rotate very slowly; however, since the refrigeration system remains deenergized, no refrigeration will occur to aggravate the frozen condition of the auger. Eventually, the auger will clear itself and the rotational speed thereof will increase until such time as the centrifugal actuating mechanism permits the terminals of the switching device to close, thereby completing the electrical circuit between the power source and the refrigeration system, resulting in the temperature within the ice forming chamber being lowered until freezing conditions exist therewithin so that the normal production of flaked ice may resume.

In the event the auger becomes frozen within the ice forming chamber while the apparatus is operating, for example, when the water inlet line or ice discharge spout become restricted, the rotational speed of the auger will be reduced below the aforesaid level, whereby the centrifugal actuating mechanism will be biased to a position opening the switch terminals, with the result that the refrigeration system will be deenergized. With the refrigeration system thus deenergized, the auger will have an opportunity to clear itself due to continued operation of the drive motor thereof, so that rotation of the auger will eventually reach the normal operating speed, at which time the centrifugal actuating mechanism will close the switch terminals to reenergize the refrigeration system.

SUMMARY OF THE INVENTION This invention relates generally to improvements in apparatus for producing and dispensing ice and, more particularly, to a new and improved apparatus for producing ice in flaked or particulate form and incorporating a control system adapted to obviate the possibility of the ice dispensing mechanism thereof from freezing up and possibly damaging the apparatus.

It is accordingly a general object of the present invention to provide a new and improved ice producing and dispensing machine.

It is a more particular object of the present invention to provide a new and improved ice making machine of the above character incorporating a control system adapted to selectively control energization of the flaked ice producing section thereof.

It is another object of the present invention to provide a new and improved ice making machine of the above character wherein the control system is adapted to selectively energize the refrigeration system thereof.

It is still another object of the present invention to provide a new and improved ice making machine of the above character wherein the control system is responsive to the rotational speed of the ice dispensing auger to selectively energize and deenergize the associated refrigeration system.

It is yet another object of the present invention to provide a new and improved apparatus of the above character which utilizes readily available component parts and is therefore economical to commercially manufacture.

It is another object of the present invention to provide a new and improved apparatus of the above character wherein the control system thereof is of a durable construction and may be easily installed.

Other objects and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic representation of an ice producing machine embodying the principles of the present invention;

FIG. 2 is an enlarged side elevational view of a portion of the control system of the machine illustrated in FIG. 1, as taken substantially within the oval 2 thereof;

FIG. 3 is a transverse cross-sectional view taken substantially along the line 33 of FIG. 2, and

FIG. 4 is a schematic representation of a portion of the electrical circuit incorporated in the ice producing and dispensing machine of the present invention.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring now to the drawings, a flaked or particulate ice producing machine 10, in accordance with a preferred embodiment of the present invention, is shown as comprising an exterior housing or cabinet schematically indicated at 12, that encloses an ice storage bin or reservoir 14 having suitable insulated side and

bottom wall sections

16 and 18, respectively, and a cover member 20. Also disposed within the cabinet 12 is a refrigeration system, generally designated by the numeral 22, of a type well known in the art and including a condenser 24, a compressor 26 having an electrically energized drive motor (not shown), and cooling fan assembly 28.

The refrigeration system 22 serves to circulate refrigerant through suitable refrigerant conduits or lines 30 to and from a particulate ice producing mechanism, generally designated by the numeral 32, that is disposed within the cabinet 12 adjacent the ice reservoir 14. It may be noted that the ice producing mechanism 32 per se does not constitute a material part of the present invention and therefore, with the exception of the following general description thereof, will not be described in detail. By way of example, the mechanism 32 may be of the type shown and described in the US. Pat. of Trow, et al., Pat. No. 2,753,694, issued July 10, 1956, which is incorporated herein by reference as a part of the descriptive portion of this application.

Generally speaking, the ice producing mechanism 32 comprises a freezing section 34 that includes a generally upright cylindrical ice forming compartment 36 that is surrounded by a series of cooling coils 38 comprising the evaporator section of the refrigeration system 22. As illustrated in FIG. 1, the coils 38 are communicable with the compressor 26 through the refrigerant lines 30. The ice forming compartment 36 is connected through a suitable conduit 40 to a source of water in the form of a storage tank 42 which is provided with a float valve or the like 44 for controlling the water level therewithin. Located interiorly of the ice forming compartment 36 is an ice conveying auger 46 comprising a central shank section 48 around which a continuous helically arranged ice conveying ramp or blade 50 is provided. The auger 46 is adapted to be rotated within the compartment 36 by means of a suitable drive shaft 52 that is drivingly connected at the upper end thereof to the auger shank section 48 and at the lower end thereof to a suitable gear reduction unit 54 that is driven by a suitable electric motor '56. As illustrated in FIGS. 1 and 2, the motor 56 comprises a generally vertically disposed output shaft 58 and is enclosed within a protective casing or housing 60. In operation, the auger 46 is adapted to convey ice that is formed around the inner periphery of the compartment 36 upwardly to a suitable ice dispensing spout or chute 62 that is located at the upper end of the compartment 36, suitable means being provided in the upper end of the compartment 36 for assuring that the ice conveyed upwardly from therewithin is in particulate form when it is delivered to the chute 62. As illustrated in FIG. 1, the chute 62 has a downwardly inclined wall 64 that is adapted to direct the particulate ice conveyed to the chute 62 into the adjacent storage bin 14. A suitable thermostatic control element 66 is provided in the upper portion of the storage bin 14 and connected in a manner later to be described with the refrigeration system 22 and drive motor 56 to shut off further freezing and delivery of particulate ice to the bin 14 when the quantity of ice chips therewithin reaches a predetermined level.

It will be noted that while the particular arrangement of the aforementioned refrigeration and ice producing components is not essential to advantageous use of the various hereinafter described features of the present invention, their combination with the present invention provides a completely self-contained unit that will serve to efficiently and conveniently furnish ice in flaked or particulate form.

In accordance with the principles of the present invention, the ice producing machine is provided with means for selectively controlling energization and deenengization of the refrigeration system 22 under certain adverse operating conditions, whereby the refrigeration system 22 will not be initially activated in the event the auger 46 is partially frozen within the compartment 36, or in the event either the water inlet conduit 40 or discharge spout 62 are restricted when the ice producing machine 10 is initially turned on or become restricted after operation of the machine 10 has begun. In general, such control means is in the form of an electrical control circuit incorporating a switch means adapted to control the flow of electric current to the refrigeration system 22, and an actuating mechanism adapted to open and close the terminal of the switch means in response to the rate of rotation of the auger 46, or, more precisely, the rotational speed of the output shaft 58 of the drive motor 56, whereby the refrigeration system 22 will not bge prematurely energized or remain energized to aggravate the frozen condition of the auger 46 within the ice forming compartment 36.

More particularly and as illustrated in FIG. 4, the control means is incorporated within that portion of the electrical circuit of the machine 10 comprising a pair of primary electrical conductors 68 and 70 which are adapted to be connected to a suitable source of electrical power, for example, a commonly available source of 110 volt electrical power. The conductor 68 is connected through a conductor 72 to the armature 74 of the thermostatic control element 66 located within the storage bin 14. The armature 74 is provided with a movable terminal or contact 76 that is selectively engageable with a fixed contact 78 connected through a conductor 80 with the electrically energized fan motor 82 of the fan assembly 28, the motor 82 also being connected to the primary conductor 70 through a suitable conductor 84. The drive motor 56 for rotating the auger 46 is connected to the

conductors

70 and 80 by means of suitable conductors 86 and 88, respectively, with the conductor 88 also being connected through a conductor 90 with the armature section 92 of a control assembly, generally designated 94, that will hereinafter be described in detail. The armature section 92 is provided with a movable contact 96 that is adapted to selectively engage a fixed contact 98 connected by means of a conductor 100 with the compressor drive motor of the refrigeration system 22, which compressor motor is in turn connected by means of a conductor 102 with the primary conductor 7 0. Generally speaking, it will be seen from FIG. 4 that when the contacts 76 and 78 are engaged, electric current will be communicated from the conductor 68 to the drive motor 56, and that when the contacts 96 and 98 are engaged, a circuit will be completed from the conductor 88 to the conductor 100, whereby to communicate electric current from the conductor 68 to the compressor motor of the refrigeration system 22. As will hereinafter be described in detail, the control assembly 94 is adapted to be selectively actuated in response to the rotational speed of the auger 46 whereby to open and close the contacts 96, 98 and thus selectively control energization and deenergization of the compressor 26 in accordance with the operating conditions existing within the ice forming compartment 36 of the machine 10.

Referring now in detail to the control assembly 94, as

best shown in FIGS. 2 and 3, said assembly is preferably although not necessarily mounted within the upper end of the motor housing 60 adjacent the upper end of the output shaft 58. The assembly 94 comprises a switch mechanism, generally designated 104, incorporating the aforesaid armature 92 and contacts 96, 98 therein and having a pair of

terminals

106 and 108 which are adapted to be connected in a conventional manner to the conductors and 90, respectively. The mechanism 104 comprises an on-off plunger 110 which is movable in a generally vertical direction between the solid line position shown in FIG. 2, wherein the contacts 96 and 98 therewithin are disengaged, to the dotted line position shown in FIG. 3 wherein the contacts 96 and 98 are engaged so as to complete a circuit between the

terminals

106 and 108. In other words, when the plunger 110 is in the solid line position shown in FIG. 2, the circuit from the conductor 90 to the compressor 26 is open, and when the plunger 110 is disposed in the dotted line position in FIG. 2, the circuit between the conductor 90 and compressor 26 is closed. The switch plunger 110 is preferably spring biased downwardly so that in the absence of any force moving the plunger 110 to the solid line position in FIG. 2, said plunger 110 will assume the dotted line position in this figure.

In accordance with the principles of the present invention, means is provided directly adjacent the lower side of the switch plunger 110 for effecting vertical movement thereof and thus actuation of the switch 104 in accordance with the rate of rotation of the ice dispensing auger 46, or more particularly, in response to the rate of rotation of the output shaft 58 of the drive motor 56, which, as hereinbefore described, is connected through the gear reduction unit 54 and drive shaft 52 with the auger 46. Such means for selectively actuating the plunger 110 is provided by a centrifugal actuating mechanism 112 that is mounted on the upper end of the output shaft 58 directly below the switch plunger 110 and is adapted to rotate as a unit with the shaft 58. The actuating mechanism consists broadly of a base plate 114, a toggle plate 116 and a shoe member 118. The base plate 114 is generally circular in shape and concave upwardly, as shown by the broken-away section of FIG. 2. The plate 114 is formed with a central annular opening 120 defined by an upwardly extending flange section 122 adapted to be fixedly secured to the outer periphery of the output shaft 58 which extends upwardly through the opening 120. The base plate 114 is formed with three equally circumferentially spaced openings around the periphery thereof, one of which is shown in FIG. 2 and designated by the numeral 124, the openings 124 being arcuate shaped at their radially inner edgest to conform to the curvature of each of three hereinafter to be described centrifugal weights, generally designated 126.

The toggle plate 116 is mounted directly above the base plate 114 and is fabricated of a spring steel material and, for example, may be stamped out of a cupped disk of flexible spring steel. The plate 116 comprises a narrow frusto-conical ring portion 128 having three arcuate, generally L-shaped fingers 130 formed integrally therewith and extending inwardly toward the center of the ring portion 128 and substantially tangent thereto. Each finger 130 is bent at the radially inner end thereof to form a generally V-shaped hook portion 132, and one of a plu rality of holes or weight retaining openings 134 are located in the ring 128 adjacent the juncture point of each of the fingers 130 therewith, as best seen in FIG. 3.

The centrifugal weights 126 are preferably identical in size and each comprises an axial stud portion 136 of reduced diameter which is adapted to be inserted within one of the openings 134 in the ring portion 128, with the stud portions 136 extending upwardly through the openings 124 of the base plate 114. Preferably, some type of resilient mounting grommet 138 is provided on each of the stud portions 136 at the juncture thereof with the 7 periphery of the openings 124 in the base plate 114.

The shoe member 118 is provided with a central hub section 140 which extends downwardly from the lower side thereof, the section 140 having three radially outwardly extending 'boss portions 142 formed integrally thereon and spaced equally circumferentially therearound. The boss portions 142 have the upper sides thereof formed in a generally V-shaped configuration and are adapted to receive and support the hook portions 132 of the fingers 130 thereon, with the result that the shoe member 118 is fixedly secured to the radially inner and uppermost ends of the fingers 130, as illustrated in FIG. 2.

During such time as the output shaft 58 is not rotating or is rotating at a relatively slow rate, the shoe member 118, fingers 130, centrifugal weights 126, and switch plunger 110 will be disposed in the solid line positions illustrated in FIG. 2. As the rotational speed of the output shaft 58 increases, the weights 126 are adapted to pivot outwardly under the influence of centrifugal force, As the centrifugal force increases, the weights 126 exert a twisting, torosional or flattening force upon the toggle plate ring portion 128. The frusto-conical shape of the ring portion 128 causes it to resist this twisting or flattening action, whereby the plate constantly exerts a positive tension in a direction to restore itself to its normal frustoconical shape. As the centrifugal force continues to increase with an increase in the rotational speed of the shaft 58, the torsional force created by the outward movement of the weights 126 builds up until a predetermined speed is reached, at which time the toggle plate 116 suddenly flattens out. As a result of this flattening action of the plate 116, the shoe member 118 attached to the ends of the fingers 130 is suddently biased axially downwardly or retracted toward the base plate 114 and away from the switch mechanism 104, as shown by the dotted lines in FIG. 2, with the result that the plunger 110 will move from its solid line position in FIG. 2 to the dotted line position shown in this figure. The shoe member 118 will remain in this retracted position until such time as the rotational speed of the output shaft 58 decreases below a predetermined amount, at which time the weights 126' are pivoted inwardly to the solid line position shown in FIG. 2, whereby the shoe member 118 Will again be biased by means of the toggle plate 116 from the dotted line position in FIG. 2 to the solid line advanced position, resulting in the switch plunger 110 being moved from its dotted line position to its solid line position. It will be noted that in a preferred construction of the present invention, the actuating mechanism 112 is mounted such that when the shoe member 118 is in its dotted line retracted position, said member 118 is not engaged with the lower end of the switch plunger 110, thus preventing any frictional wear of either of these members during rotation of the mechanism 112 on the shaft 58.

Referring now to the overall operation of the ice producing machine 10 of the present invention with particular reference being made to the schematic representation of the control circuit illustrated in FIG. 4, assuming that the conductors 68 and 70 are connected to a suitable source of electrical power, that the armature 74 of the thermostatic control element 66 is biased to its closed position wherein the contacts 76 and 78 are engaged, and that the switch plunger 110 and shoe member are disposed in their respective solid line positions in FIG. 2, at such time as the machine 10 is initially turned on, an electric circuit will be completed to the fan motor 82 of the fan assembly 28, as well as to the drive motor 56, resulting in energization of these motors. As previously mentioned, during such time as the drive motor 56 is not operating, the components of the actuating mechanism 112 are disposed in the solid line positions in FIG. 2 and the armature 92 of the switch mechanism 104 is arranged such that the contacts 96 and 98 are disengaged, thereby providing an open circuit condition between the conductor 88 and the drive motor of the compressor 26. During normal operating conditions, once the machine 10 is turned on, the drive motor 56 will cause the output shaft 58 to rotate at sufiicient speed whereby the shoe member 118 of the actuating mechanism 112 is biased to its retracted position, with the result that the switch plunger 110 is spring biased to a position effecting engagement of the contacts 96 and 98 to complete an electrical circuit to the compressor 26. Accordingly, the compressor 26 will begin to operate almost immediately after the drive motor 56 is energized, whereby ice will be formed within the compartment 36 and be conveyed therefrom to the storage bin 14 as a result of normal rotation of the auger 46. At such time as the machine 10 is turned off, either manually or upon opening of the contacts 76 and 78 of the thermostatic control 66, the electric circuit to both the drive motor 56 and compressor 26 will be opened, resulting in de-energization thereof. When the motor 56 is thus shut off, the output shaft 58 thereof will cease to rotate, whereby the shoe-member 118 will be automatically biased to its advanced position, resulting in the switch plunger 110 being moved to its solid line position in FIG. 2, preparatory to the next operational cycle of the machine 10.

In the event that the machine 10 is turned on when the auger 46 is temporarily frozen within the ice forming compartment 36, it will be seen that when the drive motor 56 is initially energized, the output shaft 58 will rotate at a relatively slow rate due to the fro-zen condition of the auger 46. Accordingly, the actuating mechanism 112 will not be rotated at a sufiicient speed to cause the shoe member 118 to be retracted and consequently the contacts 96 and 98 of the switch mechanism 104 will remain open to preclude energization of the compressor 26. Thus, the refrigeration system 22 will not operate to aggravate the frozen condition of the auger 46 within the compartment 36. By virtue of the continued energization of the drive motor 56, the auger 46 will eventually clear itself within the compartment 36 and the rotational speed of the output shaft 58- will increase until the actuating mechanism 112 effects actuation of the switch mechanism 104, thereby energizing the compressor 26 to permit normal operation of the refrigeration system 22 and the production of particulate ice.

It will be seen from the foregoing description that the present invention provides a novel ice producing machine which is adapted to function effectively in producing ice in flaked or particulate form. By virtue of the novel control system incorporated therein, in the event the ice dispensing auger 46 becomes temporarily frozen after shutting oif the machine for a short period of time, or possibly during actual operation thereof, the associated refrigeration system will be automatically deenergized,

, whereby to prevent aggravation of the frozen conditions and obviate possible damage to the ice dispensing mechanism thereof. Accordingly, the ice producing machine of the present invention will have a long and effective operational life.

While it will be apparent that the preferred embodiment illustrated herein is well calculated to fulfill the objects above stated, it will be appreciated that the present invention is susceptible to modification, variation and change Without departing from the proper scope or fair meaning of the subjoined claims.

What is claimed is:

1. In combination with an ice making machine including an ice forming chamber, a refrigeration system for producing ice within the chamber, and rotatable dispensing mechanism for transferring ice from the interior of the chamber to a storage bin or the like,

power means for supplying electrical power to the refrigeration system,

circuit means for selectively communicating said power means with the refrigeration system, and

switch means for opening and closing said circuit means,

said switch means normally maintaining said circuit means in an open condition and being actuatable to close said circuit means when said dispensing mechanism rotates at a speed in excess of a preselected speed. 2. In an ice making machine comprising an ice forming chamber, a refrigerator system including a compressor for producing ice within the chamber, and a rotatable dispensing mechanism for transferring ice from the chamber to a storage bin or the like, the improvement which comprises,

a control system for communicating electrical power from a source thereof to the refrigerator compressor,

said system including switch means for selectively opening and closing an electrical circuit between said power source and said refrigerator compressor, and

means responsive to the rate of rotation of said dispensing mechanism for actuating said switch means, whereby said switch means opening said circuit between said power source and said compressor when said dispensing mechanism rotates at a speed less than a preselected speed and closing said circuit when said dispensing mechanism rotates at a speed in excess of said preselected speed so that the refrigeration system will be automatically deenergized in the event that the dispensing mechanism tends to become frozen within the ice forming chamber, thus alleviating the freezing conditions within the chamber until proper operation of the dispensing mechanism is resumed.

3. The invention as set forth in claim 2 wherein said means for actuating said switch means comprises a centrifugal actuating mechanism.

4. The invention as set forth in claim 2 wherein said dispensing mechanism comprises an ice conveying means rotatably mounted within said ice forming chamber, and wherein said means for actuating said switch means is operable in response to the rate of rotation of said ice conveying means.

5. The invention as set forth in claim 2 wherein said dispensing mechanism comprises auger means and drive motor means for rotating said auger means, wherein said means for actuating said switch means comprises a centrifugal actuating mechanism having an actuating portion movable between advanced and retracted positions, and wherein said switch means is operable to close said circuit when said actuating portion moves to said retracted position and to open said circuit when said actuating portion moves to said advanced position.

6. In the method of operating an ice producing machine having an ice forming chamber, a refrigeration system for producing ice within the chamber, and a relatively rotatable dispensing mechanism for transferring ice from the chamber to a storage bin or the like, the steps which include,

maintaining an electrical circuit between a source of power and the refrigeration system in an open condition when the rotational speed of the dispensing mechanism is less than a preselected speed, and closing the electrical circuit between the source of power and the refrigeration system to energize said system when the rotational speed of said dispensing mechanism is in excess of said preselected speed.

7. The method as set forth in claim 6 in which said closing of the electrical circuit is accomplished by a centrifugally actuated switch in response to said preselected speed.

References Cited UNITED STATES PATENTS 2,076,816 4/1937 Hess 73-59 3,191,398 6/1965 Rader 62354 X 2,034,213 3/1936 Smith 62138 X 3,108,449 10/1963 Lents 62-354 X 3,365,901 1/1968 Guard 62354 X WILLIAM E. WAYNER, Primary Examiner US. Cl. X.R. 62-354