US 3046754 A
Description (OCR text may contain errors)
July 31, 1962 w. G. KNxFFlN ICE MAKER CONTROL SYSTEM 6 Sheets-Sheet 2 Filed oct. 2o, 1960 INV EN TOR.
C l fll//lll/l I I I July 31, 1962 w. G. KNIFFIN ICE MAKER CONTROL SYSTEM 6 Sheets-Sheet 3 Filed Oct. 20. 1960 INVENTOR. MQ/faz' KVI/fix BY HIS A7727 EY i@ fl July 31, 1962 w. G. KNIFFIN 3,046,754
ICE MAKER CONTROL SYSTEM Filed OCT.. 20, 1960 6 Sheets-Shea?l 4 l H15 YTORNEY July 31, 1962 w. G. KNIFFIN 3,046,754
' IcE MAKER CONTROL SYSTEM Filed Oct. 20, 1960 6 Sheets-Sheet 5 IN V EN TOR.
Hfs Afro/Mfr July 31, 1962 w. G. KNIFFIN ICE MAKER CONTROL. SYSTEM 6 Sheets-Sheet 6 Filed Oct. 20, 1960 United States Patent O 3,046,754 ICE MAKER CONTRQL SYSTEM Walter G. Kniin, Dayton, Ohio, assigner to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed Oct. 20, 1960, Ser. No. 63,851 Claims. (Cl. 62-135) This invention relates to refrigeration and particularly to a control -arrangement or system for rendering an ice block making and ejecting apparatus automatic in operation.
The control system herein disclosed is especially applicable to anice block maker of the type disclosed in the copending application of -Arthur I. Frei, Serial Number 741,256 filed June 11, 1958, now Patent No. 2,971,346 dated 'February 14, 1961, entitled Refrigeration, assigned to the assignee of this application, and/or to ice makers of a character similar thereto wherein ice blocks are ejected from a mold solely in response to pressures developed in the mold itself by differentially freezing water therein.
An object of the invention is to provide an improved, simplified and inexpensive electric control system for an ice block making and harvesting apparatus.
Another object of the invention is to render a control system for an ice making apparatus responsive to a heating means lassociated with an ice block mold which applies heat to the mold after ice `blocks have been ejected therefrom, as distinguished from employing a control to initiate heating of the mold and utilizing such heat for thawing and releasing ice blocks from a mold.
Another object of lthe invention is to provide a control system for an ice block making apparatus with a delay means which is electrically energized or activated after ice blocks have been ejected from a mold of the apparatus to determine the elapse of a predetermined period of time between heating of the mold and filling same with water.
A further object of the invention is to provide in a control system for an automatic ice block producing apparatus having a weight actuated ice storage receptacle, a combined holding and cut-off device which will not interfere with an ice block freezing cycle of the apparatus once it has been initiated and which will restore the apparatus to automatic operation in response to a future demand for production of ice blocks thereby.
In carrying out the yforegoing object, it is a still further object of the invention to provide a combined holding and cut-off switch device in an electrical control system of an ice block making apparatus which includes a permanent magnet attracting an ice block storage receptacle and suspendingly holding the receptacle supported above its mounting means so that the switch of the device is responsive to the weight of ice blocks in the receptacle for rendering the control system effective and ineffective.
A more specific object of the invention is to provide an improved method of controlling an ice block making apparatus and novel combinations of elements and arrangement of parts of the control system therefor to thereby render such an apparatus practical and positive to produce ice blocks as needed and to interrupt the production of ice blocks when they are not required or desired without impairing subsequent functions of the control system when more ice blocks are to be produced by the apparatus.
Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein a preferred embodiment of the present invention is clearly shown.V
In the drawings:
FIGURE l is a front view of a multiple compartmented ICC refrigerator cabinet with the doors of compartments open showing an automatic ice maker located in the freezing compartment thereof;
VFIGURE 2 is an enlarged fragmentary sectional view taken along the line 2 2 of FIGURE 1 showing a side view of the ice maker within the freezing compartment of the refrigerator;
FIGURE 3 is an enlarged fragmentary sectional View taken along the line 3 3 of FIGURE 2 showing a portion of a mold of the ice maker yfilled with water adapted to be solidified therein;
FIGURE 4 is a fragmentary `sectional view similar to FIGURE 3 and shows an ice block being popped out of the mold and directed into 1an ice block storage receptacle;
FIGURE 5 is another fragmentary sectional View through molds of the ice maker and is taken along the line 5 5 of FIGURE 3;
FIGURE 6 is an enlarged fragmentary sectional view taken along the line 6 6 of FIGURE?. showing a combined ice storage receptacle holding and switch device of the ice maker;
FIGURE 7 is another fragmentary sectional View of the combined receptacle holding and switch device taken along the line 7 7 of FIGURE 6;
FIGURE 8 is a view similar to FIGURE 6 with the ice receptacle lowered with respect to the combined device and with the switch thereof opened;
FIGURE 9 is a view partly in elevation and partly in section of a time delayvrelay of a control system for the ice maker connected to an electric circuit thereof shown diagrammatically;
FIGURE 10 is a sectional View throughcne portion of the relay disclosed in FIGURE 9 and is taken along the line 10 10 thereof; and
FIGURE 1l is a sectional view through another por-` tion of the relay disclosed in FIGURE 9 and is taken along the line 11-11 thereof.
Referring to the drawings, for illustrating the invention, there is shown in FIGURE Vl an ice making apparatus embodied in a household refrigerator having a refrigerating system associated therewith. The refrigerator includes a cabinet 10 provided with an upper insulated unfrozen food storage compartment 11, normally closed by a door 12, and a lower insulated freezing or frozen food storage compartment 13, normally closed by a door |14, separate from compartment 11 which compartments are adapted to be cooled by cold air circulated therein. The refrigerating system associated with refrigerator cabinet 10 includes a finned type refrigerant evaporator coil 16 (see FIGURE 2) mounted in a suitable air circulating duct means AI7, having inlet and outlet openings 18 and 19 respectively, for compartment -13 and a platelike pressure welded sheet metal refrigerant evaporator 21 mounted in an air circulating duct means 22, also having outlet and inlet openings 23 and 24 respectively for compartment 11. The refrigerating system also includes a motorcompressor unit, a refrigerant condenser and suitable pipe or conduit connections (not shown) with the evaporators for circulating refrigerant in succession first through evaporator 16 and thence through evaporator 2'1. Conventional controls may be interposed in an electric circuit for the refrigerator so as to control operations of the motor-compressor unit, as is well known to those skilled in the art. yIn order to maintain the temperature of air in compartment l13 between, for example, 0 and 10 F., evaporator 116 is normally at a verylow temperature and the evaporator 21 is `at a higher temperature to maintain air within compartment 11 at approximately 40 F. The air in both compartments 11 and 13 is forcefully circulated throughout their interiors. A Ifan or blowerv 26 is driven by an electric motor 27 and circulates air from compartment 13 into the inlets I18 of duct means 17 over evaporator 16 and thence through the outlet 19 back into the freezing compartment. A similar arrangement is employed for circulating air within the higher temperature unfrozen food storage compartment 11. Reference is made to the L. I. Mann Patent 2,912,834 dated November 17, 1959 and to the copending application of L. I. Mann and E. C. Simmons, Serial No. 725,652 tiled April l, 1958, noWiPatent Number 2,959,936 dated November 15, 1960, both assigned to the assignee of the present application, for a more specific or full disclosure of the type of refrigerating `apparatus herein shown.
fAn ice block freezing device or making apparatus is incorporated in the household refrigerator herein dis- Y closed which is an improved device over that shown in the A. J. Frei patent hereinbefore identified and is claimed in the copending application of A. J. Frei and W. G. Kniffin entitled Ice Block Maker, Serial Number 63,850, filed on even date herewith and assigned to the assignee of this application. An electric circuit is provided for rendering a device or apparatus of the character referred to in said applications automatic in operation to make ice blocks as needed for table use or for chilling drinks in glasses. The ice making device or apparatus presently disclosed forms an integral part of the refrigerator 10 and the electric circuit of the ice maker is connected to the electric circuit of the refrigerator which is employed to energize the electric motor of 'the motor-compressor unit of the refrigerating system associated with cabinet 10 and the electric motors for the air blowers such as motor 27. The ice maker includes an assembly located within freezing or frozen food storage compartment 13 of refrigerator 10 and this assembly comprises, a mold, generally represented by the reference numeral 30 in FIGURE 2 of the drawings, an electric heater for the mold, a temperature responsive switch, a Water filler cup-like member or funnel for the mold and a shroud or mold cover. Mold 30 is in the form of a unitary metal element, preferably cast from aluminum alloyV material, provided with water receiving and retaining chambers and an integral passageway containing the mold heater which has a steel sheath therearound and is preferably molded in place within mold 30 during the casting thereof. The mold 30 includes an upper extension 31 which is secured by screws or bolts 32 (see FIGURES 3 and 4) to an upright wall of a metallic liner 33 of come partment 13 and is substantially insulated froml this metal liner by a plastic or the like insulating pad or spacer 34 whereby the mold is cooled solely by the chilled circulating air in the freezing compartment. Mold 39 has a plurality of integral walls which are immovable relative to each other and define a row of superimposed chambers. For example, a row of cavities or open-top chambers 36 are provided in one or the upper portion of mold 30 and a row of chambers 37, preferably cylindrical in cross-sectional contour, are provided in another or the lower'portion thereof. A restrictor opening or restricted passage 38, of less magnitude than either of the chambers, connects each of the plurality of superimposed chambers 36 and 37 to one another so as to establish communication therebetween.` It is to be noted that the upper wall parts of chambers 37 are inclined toward the restricted passages 3S and these wall parts form or provide each chamber wtih a choke portion therein below and adjacent the restrictors.
Each of the cavities or open top chambers 36 may be equal in volume to the volume of a lower chamber `37 with which it communicates, if desired, and there is provided means in mold 30 for dierentially freezing Water received in and common to .the communicating upper and lower chambers. This means comprises a nonmetallic molded plastic member. or sleeve 41 lining the chambers 37 and insulating a substantial amount or a portion of water received therein from metal walls thereof. SleevesA 41, being made of a -material of ypoor heat conductivity,
form or provide retarding members or means in the mold especially in the choke portion of each chamber 37 near the restrictor passage 33. The walls of lining memberV or sleeve 41 are tapered throughout their length and the thickened end wall portion thereof is located near the restrictor or restricted passage 3S so as to effect a final freezing and expansion of a portion of the mass of water in chambers 37 closely adjacent the restricted passage within the choke portion of chambers 37 to provide a quick ejection or popping of ice blocks out of mold 30. Sealing plugs 42 are threaded into the bottom end portion of each of the bores or chambers 37 to retain the nonmetallic retarding members orl sleeves within the lower chambers and to close the bottom of these chambers. The plugs 42 each have a reduced part 43 extending into the bore of chambers 37 which is undercut circularly as at 44 to register with a water inlet passage 46 provided in mold 30 to communicate with each of the cylindrical chambers. There is a clearance between the outer diameter of reduced part 43 of plugs 42 and the wall of chambers 37 and sleeve members 41 are cut away as at 47 Y so that water directed through the passages 46 will zlow around the reduced part of the plugs through half moon-like cutouts 47 in the sleeves into the chambers. It is to be noted (see FIGURE 5) that the passages 46 connect, at one end of mold 30, to an upright feeder passage 49 provided in a boss 51 onvthe mold. Boss 51 is Where the ends or terminals of an electric heater 52 (see FIG- URES 3, 4 and 9) protrude out of the mold and this boss forms' a mounting on mold 30 for a housing containing a thermostatic snap-acting switch 48 (see FIG- URES 5 and 9) of a conventional sealed capsular or diaphragm type now well known to those skilled in the art. Thermostatic switch 48 may be of a disk actuated character including a bimetal disk which clicks or snaps over-center with temperature changes to close and open contacts thereof. The upright water feeder passage 49 continues upwardly through a stainless steel coupling 53 to a molded plastic funnel member 54, the bottom of which is substantially on a level with the top of cavities or open top chambers 36 in mold Si). Coupling 53 may be threaded into or otherwise secured to boss 51 and funnel 54 may be threaded into the coupling 53 to clamp these elements in place on the mold assembly'located within compartment 13. stands in upright passa-ge 49 to a level therein substantially equal to the level of water in cavities 36 and the switch 48 mounted in or on boss 51 is calibrated to operate in response to the combined temperature of mold boss 51 and water or ice contained in passage 49 as and for a purpose -to be hereinafter described. A nonmetallic preferably molded plastic pipe or tube 57 (see FIGURES 2 and 5) leads from a spring pressed water valve 58 (see FIGURES 2 and 9) beyond an insulated wall of chamber 13 and actuated by a solenoid 59 (see FIG- URE 9) to direct water to the interior of water funnel 54. Valve 58 is connected to a suitable source of Water supply, preferably under pressure, and is periodically opened and closed, only after ice blocks have been released from mold 30 and after heating of the mold, as will be later described herein to control flow fresh water into mold 30 during operation of the ice block making apparatus. A molded plastic or the like hood'l or-cover 55 (see FIGURES l, 2 and others) is secured, in any suitable or conventional manner, within compartment 13 and this hood or cover serves to deflect ice blocks ejected or popped out of the mold as they are flung therefrom so as to Vdirect them into an ice block storage bin or receptacle, to be presently described, removably located in the freezing compartment. Cover 55 encloses elements or parts of the apparatus and is provided with a front opening permitting removal of the ice storage receptacle from compartment 13 and replacement thereof into the compartment.
A combined ice storage receptacle holding device and Water directed to -mold 30 electric Vcurrentcut-off switch is enclosed in a molded plastic box 66 which may be mounted on a part of duct means 17 or mounted o n the liner 33 of freezing compartment 13 atthe back thereof (see FIGURES 2, 3, 4, 6 and 9). The electric switch portion of this combined device includes a lower stationar-ily mounted contact 61 and an Iupper movable contact 62 (see FIGURES 7 and 9) carried 'by a resilient spring a-rm 63. A small continuously energized electric heater 64 (see FIGURES 7, 8 and 9) is -located within box 60 and is for the purpose of preventing malfunction in the operation of elements of the combined device. The holding portion of the combined device 60 includes a permanent magnet 66 secured to a mounting and locating bracket 67 which bracket is provided with a lateral projection 68` overlying the spring arm 63 and a biasing leaf-like spring 69 straddling magnet 66. Spring 69 has curved ends abutted against side bosses formed in tbox 60 and this spring normally biases magnet 66 upwardly in spaced relation to the bottom wall of the box, as shown in FIGURE 8 of the drawings. A molded plastic ice storage receptacle 73 is removably associated with mold 30 and is adapted -to cause actuation of the combined holding device and electric switch in box 60. Receptacle 73 is located adjacent mold 30 on a mounting means in the form of a generally U-shaped lwire member (see FIGURES 2, 3 and 4). A screw or the like secures the front end of one leg of the U-shaped wire member to mold 30 and the front end of the other `leg thereof is secured, by a screw or the like, to an upright side wall of cover 55 (see FIG- URE 3). That portion of the U-shaped wire member connecting -legs thereof together is supported on a ledge cut out of or provided at the lowermost part of box 60 (see FIGURES 6, 7 and 8). Legs of the U-shaped wire member prov-ide opposed horizontal rails 74 for supporting receptacle 73 within compartment 13 with the bottom of the receptacle spaced above the compartment floor or air duct means 17. An iron or steel plate 76 is fixed, in any suitable or well known manner, to the upper part of rear end portion of .receptacle 73 (see FIGURES 6, 7 and 8) and is adapted to be attracted by magnet 66 to hold the rear end portion of the receptacle above its mounting means or rails 74, as shown in FIGURES 2, 3, 6 and 7 of the drawings, and to cause the magnet to actuate contact 62 of the electric switch of the device Within box 60. Receptacle 73 is adapted to cooperate with the combined holding device and cut-olf switch in box 60 for interrupting theelectric circuit to the ice mak-` ing apparatus as and :in a manner to be hereinafter described.
Electric Circuit An electric circuit is provided for the ice making apparatus to cause same to successively produce ice blocks as long as a demand for ice blocks exists. This circuit includes, in addition to solenoid 59, heaters 52 and 64, the sealed or capsular switch 48 in boss 51 and the combined holding device and cutoif switch in box 60, with which :ice receptacle 73 is associated, a time delay means or relay generally represented by the numeral 75 (see FIGURE 9) and located outside freezingcompartment 13 (see FIGURE 2). Time delay relay 75 controls certain portions of the electric circuit for the ice block maker and governs the interval of time between an ice block freezing-releasing cycle and a mold heating-water filling cycle of mold 30 to cause the apparat-us to produce successive cycles for progressively building up a desired accumulationv of ice blocks in receptacle 73. Referring now to FIGURE 9 of the drawings, the time delay relay 75 is shown in a wiring diagram or circuit for the ice making apparatus. Relay 75 includes a mounting base 71 of insulating material ordinarily covered by a lid or closure lmember for enclosing elements thereof. The lrelay is provided with stationary terminals 77, 78, 79 and 81 for a plurality of wire connections thereto. Terminal 77 has one end of a cantilever spring arm S2 secured thereto and the other end of this arm carries a contact 83 normally biased by arm 82 -into engagement With a stationary contact 84 `mounted on base 71. Terminal 78 has one end of a movable sbimetal arm 86 secured thereto and the other end of this arm Iis interlocked to a movable nonmetallic insulator plate 87. Arm `236 carriesl an adjustable contact S8 adapted to be engaged, at a certain time, by a contact 89 mounted on a movable arm 91 having its one end secured to terminal 79with its other end passing through an elongated clearance opening 90 provided in plate S7 to permit movement thereof in the opening relative to the plate for la purpose to be hereinafter described. rllhe contacts 88 and 89 form the timing contacts of relay 75. A bent toggle spring 92 has its one end pivotally anchored to a stud 93 on base 71 and its other end 'bears against the free end of arm 91. Toggle spring 92 provides arm 91 with a snap action ywhen this arm moves the spring past centerof its pivotal mounting on stud 93 as and for a purpose to be hereinafter described. A wall of the clearance opening 90 in plate 87 forms a stop for -arm 91 in one direction `of movementv thereof and an-adjustable stud 94 secured to base 71 forms a stop for arm 91 -in its other direction of movement. Terminal 79 also has one end of a bimetal arm 96 secured thereto and the opposite end of arm 96 is anchored to plate 87 for simultaneously' moving this plate and bimetal arm S6. Terminal 81 has one endvof a cantilever springv arm 97 secured thereto with its other end normally abutting a stop stud 98 on base 71. Arm 97 carries a contact 99 which is adapted to engage a stationary contact 101 connected by a conductor 102 im'- bedded under relay base 71 and connected with relay terminal 79. Conductor 102 forms a portion of aholding circuit of the electrical system While the relay 75 is activated to provide a timed delay between heating of mold 30 and refilling chambers thereof with Y water. Toggle spring 92 normally biases arm 91 into engagement with platev 87 to force this plate into abutment with the free end of arm 97 to thereby separate the timing contacts 88 and 89, contacts 99 and 101 while contacts 83 and 84 are in engagement with one another. This is the normal position of elements of relay 75 when the relay is not energized and activated. l The bimetal arm 96 is surrounded by a coil of Vresistance-wire 103, electrically insulated therefrom, which provides a heater therefor to cause bow-ing of this arm and movement of its end connected to plate 87 and consequently movement of arms 91 and 86. One end of wire coil 103 is connected to terminal 79 and its other end is connected to a stud terminal and by a conductor 104 under base 71 to the stationary contact 84. Relay 75 inthe electric circuit of t-he ice making apparatus governs a period of time between warming of mold 30, to condition it to be replenished lwith water, and energization of the refill solenoid-operated water valve 58. Thus time means or relay 75 creates mold warming-water filling cycles and water freezing-ice ejecting cycles of operation ofthe ice making apparatus. 'It is to be noted that the electric circuit .to the various elements of the ice making apparatus includes two power lines 111 and 112 which may be branch Wires leading from a source of elect-ric current such as the power mains of the circuit of the motor-compressor unit of the refrigerating system associated with refrigerator cabinet 10. A branch wire 113 leads from power line 111 to one contact 114 of the thermostatic switch 48 and a branch wire 116 leads fromV the other Contact 117 of switch 4S to terminal 77 on time delay relay 75. A Wire 118 connected to wire 116 leads to the mold heater 52 and extends from this heater to a wire 119 attached to terminal 79 of relay 75. Wire 119 is connected to spring arm 63, carrying contact 62, of the cut-olf switch in box 60. Power line 112 :is attached to stationary contact 61 of the switch within box 60 and extends therebeyond to terminal 81 of relay 75. A wire 121 alsoattached to contact 61 7 L i leads to thelsmall heater 64 in box 60 and from this heater to a branch wire 122 connected to power line 111; The branch wire 122 leads to solenoid 59 of water valve 58 and from this solenoid to terminal 78 on the time delay relay 75.
'Operation of Apparatus Assume that the refrigerating system of refrigerator 10 has cooled compartment 13 to aV below freezing vtemperature, say, for example, between and 10 F., with ice storage receptacle 73 removed from association with mold 30 and the combined holding device and switch within box 60 is open and the ice making apparatus is inoperative. This is considered to be the usual procedure when a serviceman installs the refrigerator in a purchasers home. lIt may now be desirable to render the ice maker Within the refrigerator eifective to produce ice blocks in compartment 13 thereof and eject them into receptacle 73. Water may be initially directed into mold 30, by manually holding valve 58 open, until vall chambers in the rnold are filled preferably up to the level in the open top chambers 36 as indicated in FIG-V URE 3 'of the drawings. The receptacle v73 is therefore placed on its mounting means with its flanged top side edg'esrsupporte'd on rails 74 and is then pushed to the back of compartment 13 so as-to align plate 76`at the back ofthe receptacle vertically Iwith magnet 66 in box 60. Magnet 66 attracts plate 76 and, in addition'fto raising and holding the rear` end portion of receptacle 73 upwardly above its mounting means 74, as shown in FIGURES 2, 3, 4, 6 and 7 of the drawings, while its front end portion is supported thereon (see FIGURE 2),
also causes the magnet to move downwardly against the bias of'spring 69 within box 60 (see `FIGURES 6 and 7). The downward movement of magnet 66 carries bracket 67 therewith and consequently projection 68 on this bracket shifts spring arm 63 and contact 62 into engagement with stationary contact 61 thereby closing the electric switch portion of the combined device 60.
This completes an electric circuit from power line 112 and cut-off switch contact 61 through heater 64, in box or device 60, back to power line 111 by way of wires 121 and 122 so as to 'energize heater 64 and warm the interior of box 60, irrespective ofthe position of thermostatic switch 48, for preventing accumulation of frost or ice on elements of the combined device 60 located in freezing compartment 13. Thermostatic switch 48 is, however, now open, due tov the water filled mold 30 being warm, to prevent energization of time delay means or relay 75 and the ice making apparatus is permitted to carry out a water freezing-ice ejecting cycle. The relay 75 remains inactive while the water in mold 30 is being chilledby cold-air within compartment 13. Asthe temperature of'water 'in' mold 30 lowers below 32 F., noncmetallic lining sleeve or retarding member 41 creates a differential freezing of water inthe chambers 36 and 37, since the member 41 insulates a portion of water in chambers 37v from metal walls thereof, and since walls of the open top cavities or chambers 36 are much thinner than wallsY of chamber 37 walls of chambers 36 more rapidly transmit heat from water in chambers 36 to the cold air ambient thereto. By this differential freezinga solid block of ice is formed or frozen in each of the chambers 36 before freezing the mass of water in chambers 37. Continued, and simultaneous cooling of both parts or portions of mold 30, having the chambers 36 and 37rtherein, within compartment 13 after formation of the solid ice blocks in `chambers 36 then ages 38, a single sudden bumper impact to the solidV ice blocks in the open-top chambers 36 and; this impact pops the blocks out of chambers'36and simultaneously ings them beyond walls of mold 30. It is to beunder?` stood that prior to this time the small or thin body of Water about the reduced water inlet portion 44 of sealinlg Y plugs 42 has frozen solid to block oif communication between lower portions of cylindrical chambers 37. When final freezing of Vthat portion of the water in the insulated choke portions of chambers 37 occurs, it rapidly expands or explodes, and since water in passages 38 has already been frozen, there is no ash of liquid from the confining or captive chambers 37. As the ice blocks are ung from mold 30 they strike the deector or hood 55 over the mold and are directed thereby into ice' storage receptacle 73 where they are exposed to the chilled air within compartment 13 to prevent thawing of the ejected blocks. The chilled air in compartment 13 then further cools mold 30, after all ice blocks have been popped therefrom, to atemperature well under 32 F., say, for
example, to Y10 F. or therebelow. Thermostatic s witch '48 isset to 'be actuated in response to a temperature of approximately 15 F. and, therefore, closes to energize and activate the relay V75 for initiating a timed Warming of'mold 30 and a delayed water filled period thereof.y
Activation of relay 75, under the influence of heater 1413, with thermostatic switch 48 closed energizing mold heater 52 to warm the mold 30, causes movement of the elements of the relay to first close contacts 99 and 101 of a holding circuit for the mold 'heater while relay 7'5 performs its timed 'delay function. Heater 103 con-V tinues to be energized for heating bimetal arm 96 and further moves the relay elements, after contacts 99 and 101 are closed, to shift plate 87 and arm 91 whereby the plate 87 engages spring arm 82 and lifts contact 83 ott contact 84.
By this time thermostatic switch 48 has sensed the increased temperature of heated mold 30and has opened the circuit through its contacts 114 and 117 from power line 111 to relay 75. Briefly opening of contacts 83 and 84 deenergizes relay heater 103 and a subsequent timed closing of contacts 88v and 8 9 by relay 75, as will be -herinafter more fully described, energizes solenoid 59 of valve A58 to open this valve and direct water into mold 30 by way of pipe 57, funnel 54.and passage 49. Bi-
freezes and expands the mass of water in chambers 37.
Y By virtue of the thicker walled portion of lining sleeves metal arm 96 begins to cool and then moves back to its normal position. After a predetermined period of time, permitting a suicient amount of Water to be directed into mold 30, toggle spring 92 shifts timer arm 91 with .a' snap action back into its normal position. The return of arm 91 to its normal position breaks contact'89 away from contact 88 and opens the circuit through solenoid 59 whereupon spring biased valve 58 closes to terminate flow of water into mold 30. Another water freezing-ice ejecting cycle of the ice making apparatus for supplying receptacle 73 with more ice blocks is now readied to be carried out.
' Relay and Circuits Controlled Thereby Vtermination of a water freezing-ice ejecting cycle of the apparatus, the end of bimetal arm 96 opposite relay terminal 79 and the end of birnetal ar-rn 86 oppositerelay terminal 78 are interlocked with insulator plate 87 againstV movement relative thereto .and for simultaneous movement therewith. This interlock of bimetal arms 86 and 96 with plate 87 forms a deectible or unitarily movable beam in relay 75. The end of cantilever arm 91 opposite relay terminal 79 is biased, by toggle spring 92, into abutment with the right-hand wall of opening 90 in plate 87, as viewed in FIGURE 9 of the drawings, and toggle spring 92 is in an off-center position toward the right. Bimetal :beams 86 and 96 `acting as cantilevers biased to the right, force the right-hand end of plate 87 against cantilever spring arm 97 to hold it it in `abutment with stop stud 98 so as to separate contacts 99 and 101 from one another. In this normal biased position of parts or elements of relay 75 the spring cantilever arm 82 biases contact 83, carried thereon, into closed engagement with stationary contact 84 and spring 92 holds timer contacts 88 and `89 open. At the termination of a water freezingice ejecting cycle of the apparatus mold 30 is reduced to a temperature well below 32 F. Thermostatic switch 48 senses this low temperature and closes contacts 114 and 117 thereof at 15 F. for activating relay 75 and energizing heater 103, associated with or surrounding bimetal arm 96, and heater 52 contained in mold 30. This energized circuit directs electric current from power line 111, wire 113, through closed switch 48, wire 116, relay terminal 77, cantilever spring arm 82, closed contacts S3 and 84, conductor 104, stud terminal y100, through relay heater 103, terminal 79, wire 119 and combined device `60 to power line 112. Since heater 52 is interposed in wire 118, which is connected Iin parallel circuit relationship With Wires 116 and 119, the mold heater 52 is energized along with heater 103 to now heat mold 30. Heat produced by heater 52 warms mold 30 to melt or thaw previously congealed or yfrozen liquid contained or remaining in chambers 37 thereof to condition the mold for receiving an additional amount of make-up water. Heat produced or generated by relay heater 103 warms bimetal arm 96 and causes it to bow to the left, as viewed in FIGURE 9 of the drawings, against the biasing eiect of spring 92. The bowing of arm 96 deilects the double bimetal beam in relay 75 and simultaneously shifts plate 87, timer arm 91, resting againstv the right-hand wall of opening 90 in this plate, and arm 86 to the left and also moves the right-hand end of plate 87 away from cantilever arm 97 whereby this spring arm automatically `shifts to the left and closes contact 99 thereon against stationary contact 101. Closing of contacts 99 and 101 completes a circuit through power line l111, wire 113, closed thermostatic switch 4S, wire 116, relay terminal 77, spring cantilever arm 82, closed contacts 83 and 84, conductor 104, stud terminal 100, heater 103, terminal 79, conductor 102, contacts 101 and 99, arm 97, terminal 81 back to power line 112. This completed circuit forms a holding circuit portion of the electrical system lfor heater 103 which is energized upon activation of relay 75 and cannot be de-energized by movement of ice storage receptacle 73, to actuate combined device `60, since ythe one power line 112 is connected to the stationary contact 61 of device 60. Thus, if relay 75 has been energized at a time when receptacle 73 may shift downwardly away from device y60 or is removed from compartment 13 of a refrigerator cabinet 10, the relay continues to carry out a mold warming and water lling cycle of the apparatus irrespective of the position of the electric switch in device 60. Continued heating and bowing of 4bimetal arm 96 moves plate 87 and arms 86 and 91 to the left. Bowing of arm 96 and the bimetal beam forces arm 91 to the left against adjustable screw 94 and shifts toggle spring 92 over center relative to stud 93 to cock the free end of arm 91 into a position lever spring arm 82 to momentarily separate contact 83' breaking of contacts 83 and 84- is a function of powerabsorbed by the bimetal beam and the making or closing of these contacts is a function of energy released by the beam prolonged oscillation of these contacts makes the device insensitive to voltage Variations within the limits of domestic usage. The time in engagement of con- -tacts 83 and 84 is a function of voltage, the time out of engagement thereof is constant, the deection is constant, therefore over the span of repeated engagement and dis- 'engagement of contacts 83 and 84 the power absorbed is averaged. Here it is to be understood that the oscillation of contacts `83 and 84 may open and close the circuit to heater 103 but this does not tie-energize and energize mold heater 52Vbecause thermostatic switch 48 is still closed directing electric current through heater 52 by way 0f power line 111, wire L13, closed switch `4S, wire 118, [terminal 79, conductor 102 of the holding circuit, con'- tacts 99 and 101, arm 97, relay terminal `81 and back to power line 112. The thermostatic switch 48 has, during the period of time of oscillation of contacts 83 and -84 in saturating bimetal arm 96 with heat to a predetermined deection, sensed the heated increased temperature of mold 30, above 50 F., and has opened the contacts -114 and 117 of this switch to de-energize heater 52 and relay heater 103, since these contacts are now out of circuit with power yline 111. With heater 103 de-energized bimetal beam and arm 96 cools `and moves to restore same from the hot saturated bowed shaped to the relatively straight normally cooled shape biased to the right. The motion of beam 96 in cooling carries insulator plate 87 and arm 186 to the right. The left end of insulator plate immediately disengages arm 82 allowing contact :83 thereon, which is normally biased to the right, to meet and close against stationary contact `84. Continued movement to the right of bimetal beam and `arm 96, plate v87 and 4arm 86, as arm 96 of the beam cools, moves adjustable contact 88 on beam arm 86 into electrical contact with contact 89 on arm 91 resting against stop 94 biased thereto by toggle spring 92. In this manner contacts 88 and `89 engage one another only after relay 75 has been de-energizedand during `an initial part of the movable cool-down period of vthe bimetal beam thereof. Closing of contacts `88 and 89 completes a circuit in the electrical system `from one side of contact 88 by way of arm 86, relay terminal 7-8, wire 122, through solenoid 59 of ow controlled valve 58 to power line 111 and from one side of contact i89 by way of yarm 91, relay terminal 79, wire 119, contacts 62 and 61 of device 60 back to power line 112. If contacts 62 and 61 are open, by virtue of movement of receptacle 73, the alternate path lfrom the same side of contact 89 is by way of arm 91, relay terminal 79, conductor 102, now closed` contacts 99 -and 101, arm 97, relay terminal 81, contact 61 of idevice 60, land to power line 1,12. Continued cooling of bimetal beam arm 96 results in -further movement of the beam and insulator plate I87 to the right whereby force brought to bear on arm 91, through the closed contacts 88 and 89, causes a continued movement of arm 91 to the right. When arm 91 carries or shifts spring 92 to the right of its over-center cocked position relative to its pivotally mounted end on stud /93 this spring will snap arm 91 into biased abutment with the right-hand wall of opening in insulator plate 87. At this instant the electrical circuit is broken .at contacts 88 and 89 thus deenergizing solenoid 59 of water iiow control valve 58.
Final cooling of arm 96 further moves the bimetal beami and insulator' plate 87 to the right and the right-hand end of plate 87 engages arm 97 deflecting it vto open contacts 101 and 99 whereafter the bimetal beam and 4plate 87 will come to rest with arm 97 in abutment with stop 98. All components of relay 75 are once yagain in their normal position. t
The energization of solenoid 59 overcomes the spring in ow control valve 58 and opens this valve to deliver a timed rate or amount of water flow or make-up water into the chambers of mold 3,0. The duration of the energized circuit through solenoid 59 is a function of time rate of restoration of the bimetal beam and arm 96 from a hot.
bowed deflection, when contacts 88 and 89 are in engagement, until a lesser deflection at a lower temperature of arm 96 causes spring 92 to snap arm 91 for de-energizing the circuit. This is determined by the distance in degrees of restored deflection that contacts 88 and 89 remm'n in contact calibrated against the rate of cooling and deflection of the bimetallic beam. Rough calibration is accornplished by material selection and ambient compensa. tion. v Fine variations vare achieved by adjustment of contact `88 on arm 86, stop stud 94, and the pivotally mounted end of toggle spring 92 on stud 93. The amount of water delivered .to mold 30 is suicient to replenish that previ-V ously frozen into iceblocks ejected ,from chambers 36 and is predetermined in accordance with a period of time between the closing and opening of contacts 88 and 89 of relay 75 and by a rate of flow of the water through valve 58. After the final cool-down period of relay 75 a Water freezing-ice block ejection cycle of the ice making apparatus now occurs and upon ejection of'ice blocks from mold B the temperature of the mold is reduced to below F. to actuate thermostatic switch 4S and Yclose the contacts 114 and i117 thereof for re-energizing a circuit to heater 52 and reactivating relay 75 so as to again re generate the system .by a water lling cycle.
Apparatus Operation Interruption When ice storage receptacle 73 receives a predetermined accumulation of ice blocks from mold30, the Weight of ice blocks in the receptacle overcomes the magnetic attraction or holding force of magnet 66 to plate '7 6, forming a part of receptacle 73, and the rear end portion of the receptacle shifts downwardly or gravitationally falls onto its located and mounting means or rails 7'4 with its Vfront end portion'pivoting thereabout. After the holding force between magnet 66 and plate 76 has been broken or over-` come biasingspring 69,'within box 60 and carried by the magnet therein, moves magnet 66 and Vconsequently bracket projection 68 upwardly to thereby permit spring arm 63 to shift contact 62 away from contact 61 to open the switch of the combined holding device and electric cut-off switch housed in box 60'. The opening of this switch breaks or interrupts the electric current supply to the electric circuit of the ice making apparatus for rendering the apparatus inoperative to produce ice blocks. Removal of a quantity of ice blocks from receptacle 73 diminishes the supply thereof therein to reduce its weight and then permanent magnet 66 will again attract plate 76 on the receptacle with suicient force to raise its rear end portion above rails 74. Thus, the rear end portion of receptacle 73 is again held above the rail 74 and is sus pendngly supported from box 60. During this shifting movement of the rear end of receptacle 73 a lug or the like provided thereon adjacent its front end pivots upon the supporting rails 74. The automatic production of ice blocks by the ice making apparatus may also (be interrupted when receptacle 73 is manually moved away from box 60 and mold 30 such as by removing the receptacle from compartment 13 for serving ice blocks therefrom into glasses of drinks at a point remote from the refrigerator cabinet 10. In this case it is to be understood that the automatic operation of the ice block making apparatus can be restored by returning the receptacle 73 to compartment d3, replacing it upon the mounting rail 7 4 and sliding same to the rear of the freezing compartment for attrac-V ing-'water filling cycles thereof. The electric circuit of our control system is devoid of expensive electrically driven motors. The iceV block making apparatus and control system may be manufactured andy sold as a packaged unit to makers of refrigerators and installed in refrigerator cabinets with a minimum amount of labor and cost. The present control system is rendered effective only after ice blocks have been ejected from a mold and Vis therefore to Y be distinguished from such systems or lcircuits that heat a mold to thaw ice blocks prior to releasing the blocks therefrom and in this respect the electric heater of the mold in the apparatus herein disclosed never applies its heat to ice blocks, consequently the frozen blocks are not warmed and remain dry throughout operations of the apparatus to thereby prevent their sticking or mouldingY to one another.
Many safety precautions are incorporated in the present electric control circuit such, for example as the warming of the combined ice block storage receptable holding and electric switch device and the electrical inactivation of the time delay relay at the moment current is directed therethrough to energize the water valve solenoid.
While the embodiment of the present Vinvention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted.
What is claimed is as follows: K
l. In combination with an ice making apparatus including a compartment, a mold within said compartment, means for directing Water into said mold, means for cooling said mold to freeze water-received therein into an ice block, means for ejecting the frozen ice block from said mold; a system for automatically controlling said apparatus comprising: l
(a) van electric heater associated with said mold for directly heating Walls thereof within said Vcompartment and effective only after the ice block has been ejected therefrom,
(b.) an electric circuit .governing said water directing means and said mold heater,
(c) switching means in said circuit operating with said mold, and
(d) a time delay relay means interposed in said circuit having an electrical connection with said Water directing means,
(e) said switching means being actuated in response to a predetermined low temperature of said mold below that at which said ejecting means ejects the ice block from the mold for simultaneously activating said relay means and energizing said heater,
(f) said switching means also being actuated in response to a temperature of said mold above 32 F. for deenergizing the mold heater while said relay means remains activated,
(g) said time delay relay means both opening and clos-v ing said water directing means after said switching means has deenergized said mold heater.
2. In combination with an ice makingk apparatus including a compartment, a mold within said compartment', means for directing water into said mold, means for cooling said mold to freeze Water received therein into an ice block, means for ejecting the frozen ice block from said thermally co-A 13 mold; a system for automatically controlling said apparatus comprising:
(a) -an electric heater associated with Vsaid mold for directly heating Walls thereof Within said compartment and effective only after the ice block has been ejected therefrom,
(b) an electric circuit governing said Water directing means and said mold heater,
(c) switching means in said circuit thermally cooperating with said mold,
(d) a time delay relay means interposed in said circuit, and Y (e) another electric heater incorporated in said relay means having an electrical connection with said water `directing means,
(f) said switching means being actuated in response to a predetermined low temperature of said mold below that at which said ejecting means ejects the ice block from the mold for simultaneously energizing said mold heater and said another heater,
(g) the energization of said another electric heater heating said relay means and activating same,
(h) said switching means also being actuated in response to a temperature of lsaid mold above 32 F. for deenergizing said mold heater While the heater in said relay means is energized,
(i) the heating of said another heater finally causing the relay means to deenergize same for a cool down period thereof,
(j) said time delay relay means both opening and closing said Water directing means after said switch- Y ing means has deenergized said mold heater and during said cool down period of said another heater for controlling oW of water into said mold.
3. In combination with an ice making apparatus including a compartment, a mold Within said compartment, a solenoid actuatable valve adapted to direct water from a source of supply thereof into said mold, means for cooling said mold to freeze Water received therein into an ice block, means for ejecting the frozen ice block from said mold; a system for automatically controlling said apparatus comprising:
(a) an electric heater associated with said mold for directly heating walls thereof within said compartment and leffective only after the ice block has been ejected therefrom,
(b) an electric circuit for governing the solenoid of said valve and said mold heater,
(c) a thermostatic switch in said circuit operated by temperatures of said mold, and
(d) a time delay relay means interposed in said circuit including a movable bimetal means and another electric heater connected therein for warming and causing movement of said bimetal means in one direction,
(e) said `switch closing in response to a temperature of said mold below that at which said ejecting means ejects the ice block from the mold for energizing said mold heater todirectly heat Walls of the mold and for simultaneously energizing said another heater,
(f) said another heater being deenergized in response to a predetermined movement of the bimetal means of said relay means in said one direction for cooling VII said bimetal means and causing a return movement thereof' in a direction opposite said one direction, (g) said time delay relay means being effective during said return movement of the bimetal means thereof for both energizing and deenergizing the solenoid of said valve to control the duration of flow of Water therethrough into said mold.
4. In an automatically operated ice making apparatus including a freezing compartment and a mold disposed therein having a plurality of immovable Walls formed integral therewith detining chambers containing water to be frozen into ice blocks wherein the blocks of ice are thereafter ejected from said chambers solely by freezing Water in said mold the combination comprising:
(a) means on and in direct heat exchange relation with a wall of said mold adapted to heat same only after ejection of ice blocks from said chambers, `and (b) thermostatic means secured to a Wall of the mold against movement relative thereto actuated in response to a low temperature thereof attained subsequent to ejection of ice blocks from said chambers for rendering said heating means effective.
5. In an ice making apparatus including a compartment, a mold disposed in said compartment having a plurality of stationary Walls formed integral therewith delining ice block chambers therein, means for directing Water into said chambers, means for cooling said mold to freeze water received in chambers thereof into ice blocks, means for ejecting 4frozen ice blocks in a dry state from the chambers solely by freezing water in said mold While all walls there/of remain immovable and a system in combination with said apparatus for automatically controlling its functions comprising:
(a) means creating consecutive water freezing-ice ejecting and mold heating-water filling cycles of the apparatus,
(b) said control system having means associated with said mold for artificially and directly heating walls thereof within ksaid compartment only -betvveen said cycles subsequent to ejection of the ice blocks yfrom chambers of the mold,
(c) said heating means being rendered effective in re- I spense to a low temperature attained by said mold below that temperature thereof at which ice blocks were ejected out of the mold chambers.
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