|Publication number||US3525232 A|
|Publication date||Aug 25, 1970|
|Filing date||Aug 30, 1968|
|Priority date||Aug 30, 1968|
|Publication number||US 3525232 A, US 3525232A, US-A-3525232, US3525232 A, US3525232A|
|Inventors||Toma Daniel N|
|Original Assignee||Gen Electric|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (4), Referenced by (6), Classifications (7)|
|External Links: USPTO, USPTO Assignment, Espacenet|
'Aug. 25, 1970 T M 3,525,232
AUTOMATIC ICE MAKER CONTROL MEANS Filed Aug. 30, 1968 2 Sheets-Sheet 1 H \S ATTORNEY Aug. 25, 1970 D. N. TOMA 3,525,232
AUTOMATIC ICE MAKER CONTROL MEANS Filed Aug. 30, 1968 2 Sheets-Sheet 2 INVENTOR.
DANEL; N- TOMA H l S ATTORNEY United States Patent O US. Cl. 62-137 9 Claims ABSTRACT OF THE DISCLOSURE A household refrigerator including an automatic ice maker, an ice bin for storing ice pieces produced by the.
BACKGROUND OF THE INVENTION Automatic ice makers of the type presently provided in household refrigerators broadly include means for automatically filling a plurality of mold cavities w th water, discharging the ice pieces formed in the cavities into a movable or removable storage bin or receptacle and then repeating this cycle. Ice-level sensing means are included for terminating the automatic operation of the ice maker when a predetermined level of ice in the storage receptacle has been reached. A known level sensing means of the type described in Pat. 3,331,215Shaw, comprises a feeler arm mechanism movable at some time during each cycle of operation of the ice maker to sense or feel the ice accumulation in the bin and to stop the operation of the ice maker when a desired quantity of ice has been stored. In order that such arm mechanism will not interfere with access to the ice pieces stored in the bin or with the discharge of ice pieces into the bin, it has been necessary to restrict the size and shape thereof so that it actually senses the level of ice at only one point or over a relatively small area of the bin. Also, since the feeler arm mechanism is associated with the ice maker, it senses the level of ice near the ice maker or more specifically immediately below one portion of the ice maker. Thus, once the ice accumulated in the bin fills up to a point where the feeler arm contacts the ice at that portion of the bin sensed by the feeler arm, the automatic operation of the ice maker is stopped regard- 3,525,232 Patented Aug. 25, 1970 restricted to fixed bins or receptacles and both the light source and the receiving unit have been permanently built into or mounted on the walls of the bin. In addition since the photocell sensing has employed a beam of light directed from the light source to the photocell, the level sensing has been restricted to the ice in the line or path less of the level of ice in the remaining portions of the bin.
It has also been proposed, as described in Pat. 3,045,445MacLeod, to employ either thermostatic sensing means or photocell means for sensing the accumulation of a predetermined quantity of ice within a storage bin and thereupon de-energize an ice maker. A thermostatic sensing means is not satisfactory for household refrigerators for a number of reasons including the fact that different users operate their freezers at different temperatures and the frequent door openings of the door to the freezer compartment adversely affect the operation of a thermostatic sensing means. The use of photocell means, as described in the MacLeod patent, has been of this beam.
SUMMARY OF THE INVENTION The present invention is directed to an improved ice level sensing means particularly adapted for use in connection with a movable or removable ice bin and is more specifically concerned with a light operated sensing means forming part of an ice maker control circuitry designed to assure the proper operation thereof under all normal conditions of use of the freezer compartment of the household refrigerator containing the ice bin.
In accordance with the illustrated embodiment of the invention, there is provided a household refrigerator including a freezer compartment containing a storage bin for collecting ice pieces produced by an ice maker. The storage bin has an opening in one wall thereof. A light sensitive means is positioned outside of the bin adjacent the opening where it is sensitive to light passing through the opening and means are provided for illuminating at least that portion of the freezer compartment containing the ice bin. The light sensitive means is part of the ice maker control circuitry which is designed so thatthe ice maker continues to operate until there is a predetermined decrease in the intensity of the light passing through the opening due to accumulation of ice in the bin. Preferably the opening is an elongated horizontal slot and the light sensitive means includes a light collecting bar coextensive with the slot. Additional aspects of the illustrated embodiment of the invention include means fon interrupting the operation of the .ice maker whenever the storage bin is moved from its ice receiving position, means for de-energizing the light source when the desired amount of ice has accumulated in the bin and means com prising the usual light for illuminating the interior of the freezer compartment when the access door thereto is opened for re-energizing the ice maker when the ice level has again been lowered below the stopping level.
BRIEF DESCRIPTION OF THE DRAWING In the accompanying drawing FIG. 1 is a front elevational view of the freezer compartment portion of a household refrigerator;
FIG. 2 is a sectional view taken generally along lines 22 of FIG. 1;
FIG. 3 illustrates one form of light collector bar suitable for use to practice the present invention;
FIG. 4 is a top view of a portion of the collector bar of FIG. 3; and
FIG. 5 is a schematic diagram of electrical circuitry for controlling the operation of the ice maker.
DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to FIGS. 1 and 2 of the drawing there is illustrated a household refrigerator including a freezer compartment 1 having an access opening at the front thereof closed by means of a closure member in the form of a door 2. An automatic ice maker 3 is mounted in an upper portion of the freezer compartment in a position to discharge ice pieces into a storage receptacle 4 suitably supported below the ice maker 3. It will be understood that the ice maker may be any of the well known types presently used in household refrigerators, the illustrated ice maker being generally of the construction shown in the aforementioned Shaw Pat. 3,331,215 except for the substitution of the ice level control means of the present invention for the feeler arm mechanism of the Shaw structure.
Also, while in the illustrated embodiment of the invention the receptacle 4 is illustrated as being supported on a bottom wall of the freezer compartment, in the adaptation of the invention to a refrigerator which includes a storage drawer within the freezer compartment, the receptacle 4 may be carried by the drawer structure in a position such that when the drawer is closed, the receptacle 4 will be in an ice receiving position below the ice maker 3.
The illustrated receptacle 4 is of a generally rectangular shape while the bottom wall 5 of the freezer includes one or more projections or stops 6 for engaging the side and rear walls of the bin to properly position the bin below the ice maker 3. Since the ice maker 3 is supported adjacent the one. side wall 9 of the freezer compartment, this side wall 9 prevents lateral displacement of the receptacle in this direction.
The receptacle 4 is, of course, of a limited storage capacity. Therefore it is necessary to interrupt the operation of the ice maker before the amount of ice discharged into the receptacle exceeds its storage capacity. However it is also desirable to avoid premature stopping of the ice maker. When a mechanical means such as a feeler arm like that described in the aforementioned Shaw patent is employed for terminating the operation of the ice maker, the operation is sometimes interrupted before the full storage capacity of the receptacle is used. For example, employing a receptacle such as that shown in FIGS. 1 and 2 of the drawing and a mechanical feeler arm such as that disclosed in the Shaw patent, the feeler arm will sense the level of ice below the open or discharge side of the ice maker 3 that is adjacent the receptacle side wall 10. Since the ice pieces are discharged into the portion of the receptacle adjacent this wall, they tend to pile up in this area so that the operation of the ice maker may be interrupted even though the ice production of a few additional cycles of operation of the ice maker could be accommodated in the receptacle since such additional ice pieces would tend to roll or slide from the top of the pile downwardly beneath the ice maker and in the direction of the left wall 11 0f the receptacle. While such premature stopping could be avoided by centering the receptacle relative to the point at which the ice pieces are discharged into the receptacle, this would tend to waste the freezer storage compartment volume between the receptacle and the freezer wall 9.
In accordance with the present invention, there is provided means operatively associated with the receptacle rather than with the ice maker for terminating the ice maker operation when the bin contains the optimum amount of ice. More specifically, the ice sensing means comprises photoelectric means comprising a source of illumination for the interior of the freezer compartment or at least that portion thereof adjacent one 'wall thereof and an opening in that wall adjacent the light sensitive means. When the intensity of the light passing through the opening and sensed by the light sensitive means decreases due to the accumulation of ice pieces in front of part or all the opening, the operation of the ice maker is interrupted.
The light source may be mounted at any convenient point above and adjacent the receptacle. In the illustrated embodiment of the invention, the light source comprises a small bulb 14 mounted by means of a bracket 15 on the discharge edge or side of the automatic ice maker 3 above the receptacle 4. This bulb 14 serves to illuminate at least that portion of the freezer compartment 1 adjacent the receptacle 4. More specifically it illuminates the interior of the receptacle 4.
One wall of the receptacle, preferably the wall 11 spaced the greater distance from the area of the receptacle into which ice is discharged by the ice maker 3 includes at least one opening 16 which is preferably in the form of an elongated horizontal slot as illustrated in FIG. 2 of the drawing. This slot is spaced from the top of the wall 11 a distance such that when the ice has accumulated to approximately the height of opposite Wall 10', the ice pieces at the wall 11 will begin to cover or partially cover the opening 15 and thereby decrease the amount of light passing through the slot opening 15.
Means sensitive to the light passing through the opening '15 is positioned on the outside of the wall 11 and in the illustrated embodiment of the invention this means is mounted on the freezer wall 9. The light sensitive means may be the usual photoelectric cell or any of the well known light-activated semiconductors such as a light activated SCR or a light activated silicon controlled switch or a phototransistor. In accordance with the illustrated embodiment of the invention, a phototransistor is employed as the light sensitive means and this element, generally indicated by the numeral 17, is mounted within a recess 18 in one end of a light collecting bar 19' which is substantially coextensive with opening 15. A phototransistor is a preferred means for sensing the amount of light passing through the opening 15 since it combines both functions of a photocell and transistor in one unit.
The light sensing element or bar 19 is a well known means for collecting light and transmitting that light to a specific point. The bar may be made for example of methyl methacrylate resin and has a light receiving face or front side 20 which is positioned opposite the opening 15 while the remaining sides and rear wall of the bar are coated with a suitable opaque paint or other coating as shown in FIGS. 3 and 4. If desired, means may also be provided for restricting the amount of light reaching the light bar along a path between the freezer wall 9 and the wall 11. For example, a flange 21 may be provided on the wall 11 immediately above and in shielding relationship to the collector bar 19. Also the rear wall of the bar may be provided with a series of arcuate grooves or slots 22 designed to reflect light and increase the transmission of light to the end of the bar containing the phototransistor 17.
Using a light collector bar in combination with a 'horizontal slot 19, the bar will scan a substantial length of the storage bin and therefore sense a build-up of ice at any point along its length as well as provide a control responsive to an average rather than a point or local buildup of ice.
The operation of the light sensing means in controlling the stopping of the ice maker when a. predetermined amount of ice is accumulated in the bin 4 will become more apparent from consideration of the control circuit shown in FIG. 5 of the drawing. The elements or components of the illustrated circuit are only those essential to the operation of the ice maker insofar as the photoelectric sensing control is concerned. The ice maker components included in the diagram of FIG. 5 and more fully described in the aforementioned Shaw patent include a motor 26 for driving the ice maker timing ejection and water fill mechanism, a mold heater 27 for warming the walls of the ice mold to facilitate the release of the ice pieces, and a thermostatic switch 28 for sensing the mold temperature and initially energizing the motor 26 and the heater 27 upon the formation of ice in the ice maker mold. The motor 26 drives a cam 29 operating a plurality of switches during an ice harvesting cycle, one of which energizes and opens a solenoid valve 30 for supplying a fresh charge of water to the ice maker mold.
When the thermostatic switch 28 senses a predetermined below freezing temperature, it closes and connects both the motor 26 and the mold heater 27 across the supply lines 31 and 32. During initial operation of the motor the cam 29 closes a first switch 33 bypassing the thermostat 28 to assure continuous operation of the motor 26 and the mold heater 27 after the heater 27 has warmed the mold to a point where the thermostatic switch 28 opens. After discharge of ice pieces from the mold, the cam 29 closes a second switch 34 for energization of the solenoid controlled water valve 30 to supply a fresh charge of water to the mold. Thereafter, rotation of the cam 29 opens both switches 33 and 34 de-energizing both the motor and the mold heater which remain de-energized until the thermostat 29 again senses a below freezing temperature.
To interrupt this automatic ice making cycle when the amount of ice accumulated in the receptacle 4 has substantially reached the capacity thereof, the phototransistor 17 is part of a control circuit including a DC regulated power supply comprising a voltage regulating Zener diode 35, a dropping resistor 36 and a rectifying diode 37 adapted to supply a low DC voltage from lines 31, 32 to the positive line 38 and negative line 39. The light 14 is connected across the lines 31, 32 through a silicon controlled rectifier (SCR) 41 and also through a circuit which includes a heater 42 and a diode 43 in parallel with the silicon controlled rectifier 41. The phototransistor 17 is connected across the lines 38, 39 in series with a high resistance 44 between the cathode of the phototransistor and the negative terminal 39. The gate 45 of the silicon controlled rectifier 41 is connected between the cathode of the phototransistor 17 and the resistance 44, the resistance 44 being of such a value that when the phototransistor is conducting, it supplies a gating signal to the silicon controlled rectifier to turn that element on. Additional elements of the circuit include a capacitor 48 and a resistance 49 connected in series with one another and in parallel with the SCR 41 to protect the SCR from high voltage transients and, if desired, a capacitor 50 connecting the gate of the phototransistor 17 to the line 39 for stabilizing the operation of the phototransistor.
A heater 42 is mounted in heating relationship with the thermostat or ice sensor 29 and biases the action of the thermostat 28 by the amount of heat supplied thereto.
In considering the operation of this control circuitry, it may be assumed that the light 14 is on and the level of ice in the bin 4 is low. The light ambient in the area of the freezer compartment containing the bin 4 is sufficient to maintain the phototransistor 17 on and with the phototransistor 17 conducting a gating signal is supplied to the silicon controlled rectifier 41. As a result current continues to flow through the light 14 and the silicon controlled rectifier 41 to maintain the light 14 on. Also with the silicon controlled rectifier 41 conducting, it shorts out the heater 42 and with no heat being supplied by the heater 42 to the thermostat 28, the ice maker operates in its normal automatic manner.
When sufficient ice accumulates in the bin 4 to decrease the intensity of the light reaching the phototransistor 17 to a point where the phototransistor no longer conducts, the silicon controlled rectifier 41 is turned off with the result that current then flows through the light 14 and the heater 42. Sufiicient heat is supplied to the thermostat 28 by the heater 42 to maintain the thermostat 28 at a temperature above its normal operating temperature or in other words at a temperature above that at which it normally closes its contacts to energize the ice maker motor 26 and ice mold heater 27. Thus the automatic operation of the ice maker is interrupted. Also, as the heater 42 is now connected in series with the light 14, the amount of light given off by the light 14 is insufficient to trigger the phototransistor on regardless of the amount of ice in the bin 4.
Since the amount of light from the light 14 is insufficient under these conditions to render the phototransistor 17 conducting, means are provided for providing the required light to render the phototransistor 17 conducting whenever the ice level in the bin has been lowered. A convenient source of this re-energizing light is the usual bulb 52 provided for normally illuminating the interior of the freezer compartment and controlled by a normally open door switch 53 which closes to energize the light 52 whenever the door 2 is open. Thus, each time the door 2 is opened, the bulb 52 provides a light ambient in the vicinity of the bin 4. After suflicient ice has been removed from the bin that the intensity of the light reading the phototransistor is sufficient to trigger the phototransistor, the silicon controlled rectifier will be gated on and the light 14 will again be fully on while the heater 42 will be shorted to return the icemaker to its normal automatic operation. In order to prevent reactivation of the ice maker by the light from bulb 52 if bin 4 has been removed from the freezer compartment or is in out of position relative to the ice maker, one of the AC supply lines 31, 32 includes a bin operated switch 54 so that the ice maker circuitry is opened whenever the bin is not in its normal position.
From the above description, it would seem that there has been provided an ice level control circuit for an ice maker which is independent of the position of the ice maker or any mechanical component thereof relative to the bin and which is adapted or tailored to the shape, capacity and positioning of the bin 4. Also the intensity of illumination of the light 14 is an indication to the user of whether the ice maker is operating and whether the bin is full, not full, or out of position.
What I claim as new and desire to secure by Letters Patent of the United States is:
1. A household refrigerator comprising an automatic ice maker, a freezer compartment containing a removable storage bin for collecting ice pieces produced by said ice maker and having an opening in one wall thereof;
control means including means for stopping the operation of said ice maker when the ice collected in said bin at least partially blocks said opening,
said stopping means comprising illuminating means above said bin for illuminating at least the portion of said compartment including said bin and light sensitive means positioned outside said bin adjacent said opening and responsive to a decrease in the intensity of light passing through said opening to a given level for stopping said ice maker.
2. The refrigerator of claim 1 in which said opening is a horizontal slot and said light sensitive means includes a light collecting bar substantially coextensive with said slot.
3. The refrigerator of claim 1 in which said bin is removably positioned in said compartment and said control means includes switch means operable upon removal of said bin to stop said ice maker.
4. The refrigerator of claim 1 in which said illuminating means is positioned generally above said bin.
5. The refrigerator of claim 4 in which said illuminating means is mounted on said ice maker.
6. The refrigerator of claim 1 in which said illuminating means is rendered ineffective upon stopping of said ice maker by said light sensitive means and said compartment contains a second periodically energized illuminating means for reactivating said ice maker when the intensity of light from said second illuminating means passing through said slot is above said given level.
7. The refrigerator of claim 6 in which said ice maker includes a thermostatic control operable in response to the freezing of water therein for discharge of ice into said bin and said control means includes a heater which is energized to prevent operation of said thermostatic control when said first illuminating means is de-energized.
8. The refrigerator of claim 6 comprising a closure member for closing-the access opening to said compartment and in which said second illuminating means is ener gized when said closure member is opened.
9. The refrigerator of claim 7 in which said control means comprises a silicon controlled rectifier for control- 7 8 ling the operation of said heater and said light sensitive 3,188,828 6/1965 Wayne 62--140 means comprises a phototransistor controlling the gating 3,196,274 7/1965 Giordmaine 250-215 X of said silicon controlled rectifier.
References Cited UNITED STATES PATENTS 3,045,445 7/1962 MacLeod 62137 62264; 250215 3,120,108 2/1964 Pansing 62140X WILLIAM E. WAYNER, Primary Examiner U.S. Cl. X.R.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US3045445 *||Dec 19, 1960||Jul 24, 1962||Carrier Corp||Ice making|
|US3120108 *||Mar 30, 1961||Feb 4, 1964||Gen Motors Corp||Refrigerating apparatus including defrost control|
|US3188828 *||Dec 4, 1961||Jun 15, 1965||Chicago Aerial Ind Inc||Photo-electric ice detecting device|
|US3196274 *||Dec 12, 1961||Jul 20, 1965||Bell Telephone Labor Inc||Light beam demodulator|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US4719765 *||Sep 19, 1986||Jan 19, 1988||Whirlpool Corporation||Ice storage receptacle light for ice maker|
|US4822996 *||Jun 3, 1988||Apr 18, 1989||King-Seeley Thermos Company||Ice bin level sensor with time delay|
|US6438976||Jun 4, 2001||Aug 27, 2002||General Electric Company||Icemaker assembly|
|US7426838||Aug 17, 2000||Sep 23, 2008||General Electric Company||Icemaker assembly|
|US20100050677 *||Aug 4, 2009||Mar 4, 2010||BSH Bosch und Siemens Hausgeräte GmbH||Refrigeration appliance with an ice maker|
|DE3711241A1 *||Apr 3, 1987||Oct 15, 1987||King Seeley Thermos Co||Eiskastenniveausensor|
|U.S. Classification||62/137, 250/215, 62/264|
|International Classification||F25C5/00, F25C5/18|