The present invention relates to ice-making machines for home refrigerators and the like and specifically to an ice-making machine providing a flexible tray for ejecting ice cubes while using an AC drive.
Household refrigerators commonly include automatic ice-makers located in the freezer compartment. A typical ice-maker provides an ice cube mold positioned to receive water from an electric valve that may open for a predetermined time to fill the mold. The water is allowed to cool until a temperature sensor attached to the mold detects a predetermined low-temperature point where ice formation is ensured. At this point, the ice is harvested from the mold by a drive mechanism into an ice bin positioned beneath the ice mold. The amount of ice in the ice bin may be checked through the use of the bail arm which periodically lowers into the ice bin to cheek the ice level. If the bail, is blocked in its descent by a high level of ice, this blockage is detected and ice production is stopped.
One method of harvesting ice cubes from the molds employs a mold heater. Typically, in this case, the ice tray will be a metal die-cast part incorporating an electrical resistance heater which heats the ice tray to release the ice when the tray is inverted by a motor. The electrical resistance heater and the ice-maker motor normally operate directly at a fine voltage of about 120 volts AC eliminating the need for additional power processing for the motor 51 or, in some reduced complexity embodiments, sophisticated control electronics in the associated refrigerator.
An alternative method of harvesting ice cubes uses a flexible ice tray which is twisted by a DC motor receiving power and control signals from an external DC power source and control electronics in the associated refrigerator. Twisting of the tray ejects the ice cubes from the tray.
This latter approach can operate with considerable energy savings but is not available on some lines of refrigerators which do not provide the necessary DC power supplies for the motor or more sophisticated control electronics for producing the necessary control signals.
The present invention provides an ice-maker using a flexible tray but operating with an AC motor to eliminate the need for DC power processing not available in some refrigerator lines. Simple and precise bidirectional control of the AC motor is provided by interacting stops on a drive gear and the bail arm The invention also provides an extremely simple user interface for an ice-maker allowing testing of the operation of the ice-maker, the outputting of error codes, and improved adjustment of tray fill level in low-pressure environments, according to a teaching routine that may be conducted by the user. In addition, the ice tray provides a mechanical and electrical connector allowing it to be replaced through a simple unplugging and plugging operation.
Specifically then, in one embodiment, the present invention provides an ice-maker having an ice tray providing multiple cube forming compartments open on an upper face of the ice tray for receiving water to mold ice. A motor unit has a connector attachable to the ice tray to rotate the ice tray for filling of the ice tray with water in a first position and warpage of the tray to discharge the cubes from the tray in a second position. The motor unit further provides: (a) an AC motor operable to rotate the connector hi-stably in two directions; (b) a first and second stop blocking the rotation of the AC motor when the tray is in the first and second positions to cause reversal of the direction of operation of the AC motor at those positions; and (c) a position sensor sensing at least one rotated location of the tray. A controller responds to the position sensor to control power to the AC motor to provide a cycling of the tray between the first and second positions for ice making.
It is thus a feature of at least one embodiment of the invention to provide an extremely simple auto reversing mechanism for use in an ice-maker.
The ice-maker may further include an ice bin positioned beneath the ice tray to receive ice cubes discharged from the ice tray in the second position and a bail arm operable by the AC motor to descend into the ice bin as the tray moves from the first position to the second position. The ice-maker may further include a third stop blocking the rotation of the AC motor when the tray is between the first and second position before warpage of the tray, and the bail arm may provide a movable finger interacting with the third stop only when the bail arm is blocked at a predetermined elevation from descent into the ice bin indicating a full state of the ice bin, the interaction of the movable finger with the third stop reversing the AC motor before it reaches the second position.
It is thus a feature of at least one embodiment of the invention to employ a stop mechanism automatically reversing the AC motor to sense and respond to a full ice bin without the need for additional bail arm height sensing contacts or the like.
The movable finger may further interact with the first and second stops to block rotation of the AC motor at the first and second stops.
It is thus a feature of at least one embodiment of the invention to use the bail arm finger to provide a common interference mechanism for the first, second and third stops eliminating the need for additional structure.
The AC motor may be an AC synchronous motor.
It is thus a feature of at least one embodiment of the invention to make use of the bi-stable reversibility of the synchronous motor to simplify the mechanism of an ice-maker. It is another object of the invention to make use of a motor that can directly receive line power without the need for voltage regulation circuitry.
The controller may operate to provide power to the AC motor when the tray is between the first and second positions and to selectively stop the AC motor at the first and second positions,
It is thus a feature of at least one embodiment of the invention to cycle the tray between various positions and to bold the tray at those positions using simple power control of an AC motor.
The connector may be axially connected to a gear having the first, second and third stops on a surface of the gear and the AC motor shaft may communicate with the gear through at least one additional gear.
It is thus a feature of at least, one embodiment of the invention to control mechanical advantage to the AC motor so that it may be indifferent to normal frictional and tray warpage forces experienced during operation of the ice tray while nevertheless being, reversible by mechanical stops.
The ice-maker may provide an electrically actuatable valve communicating with the controller to be activated by the controller for delivering water to the ice tray in the first position and may include at least one switch actuatable by a user of the ice-maker to open the valve at a first tune and close the valve at a second time indicating an amount of time necessary to fill the ice tray; and wherein the controller stores an indication of the amount of time to use to control the electrically actual:able valve at subsequent times when the tray is in the first position for filling with water.
It is thus a feature of at least one embodiment of the invention to provide a simple mechanism for the consumer to adjust for varying water pressures such as, may affect filling of the ice tray.
The ice tray includes a sensor communicating with at least one cube-forming compartment to sense the formation of ice, and the connector may releasably attach to the ice tray and include releasable electrical contacts communicating with corresponding contacts in the ice nay and wherein the sensor provides electrical signals indicating the formation of ice through the releasable electrical contacts of the connector to the controller.
It is thus a feature of at least one embodiment of the invention to provide a thermal sensing ice tray that can be readily replaced by disconnecting then reconnecting a connector providing both mechanical and electrical connection. This allows improved repairability oldie ice-maker or the ability to use a variety of different ice trays providing different sizes or ice cube geometries.
The ice tray may include a water receiving chute extending upward therefrom and providing a sloping surface diverting downwardly flowing water across the upper face of the ice tray.
It is thus a feature of at least one embodiment of the invention to reduce splashing of the water entering the ice tray at different pressures through the use of an integrated diverter chute.
The ice-maker may further include a slip ring system providing an electrical path from the releasable electrical contacts of the connector to the controller with rotation of the connector.
It is thus a feature of at least one embodiment of the invention to eliminate interconnecting wiring such as may flex and break during operation of the ice-maker and which can interfere with replacement of the ice tray if damaged during repetitive flexing.
The slip ring system may provide a set of rotating wipers attached to the connector and, communicating with stationary conductive traces to provide the slip ring system.
It is thus a feature of at least one embodiment of the invention to provide a slip ring system that can integrate with a position sensor using similar mechanism.
Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings in which like numerals are used to designate like features.
Before the embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. The use of “including” and “comprising” and variations thereof is meant to encompass the items listed thereafter and equivalents thereof as well as additional items and equivalents thereof.
Referring now to
The ice harvest drive mechanism 14 may have a drive coupling 16 exposed at a front wall 18 of a housing 20 of the ice harvest drive mechanism 14 and communicating with the mold 12 or comb. The drive coupling 16 may rotate about an axis 22 along which the ice tray 12 or comb extends.
The right wall 24 of the housing 20, flanking the front wall 18, may support one end of a bail arm 30 extending generally parallel to axis 22 allowing the bail arm 30 to pivot about a horizontal axis 32 generally perpendicular to axis 22 and extending from the right wall 24. As so attached, the opposed cantilevered end of the bail arm 30 may swing down into the ice storage bin 15 to contact an upper surface of the pile of cubes 17 in the ice storage bin 15 to determine the height of those cubes 17 and to deactivate the ice-maker 10 when a sufficient volume of cubes 17 is in the ice storage bin 15 to prevent full descent of the bail arm 30. The bail arm 30 may be a thermoplastic material attached to a rotatable shaft 36 extending along axis 32 through the housing 20.
A water valve 19 may receive tap water from a supply line 21 to provide water into the ice tray 12 under the control signals generated by the ice harvest drive mechanism 14 as will be discussed below,
Referring now to
The microcontroller 59 including a processor, computer memory holding a stored program, and input/output circuits that may communicate with other components on the printed circuit board 46, including the traces 58, provides inputs related to the rotational position of the gear 50. The microcontroller 59 may also communicate with a three-color (RGB) LED 61 as will be discussed below and a first and second switch 63. Output signals from the microcontroller 59 may control the AC motor 51 and the electric valve 19 (shown in
Referring now to
Extending radially inward from the rim 60 is a first home-stop 66 presenting a radial face that may abut the reversing arm 62 preventing further rotation of the gear 50 in a clockwise direction past the home-stop 66 as depicted. Approximately halfway around the rim 60 is an end-stop 68 also providing a radial face that may abut the reversing arm 62 preventing further counterclockwise rotation of the gear 50 past the end-stop 68. When the home-stop 66 abuts the reversing arm 62, the ice tray 12 (shown in
Partway between the home-stop 66 and end-stop 68 and extending radially outward from the center of the rear face of the clear 50 is a bin-full stop 69 having a limited radial extent presenting a gap between the outermost radial edge of the full-bin stop 69 and the inner surface of the rim 60.
Referring now to
Referring now to
The ice tray 12 again returns to its upright position at the home refill state 70c at which time the motor 51 is deactivated by the microcontroller 59. The microcontroller 59 then may activate the valve 19 for a programmable fill time that will be discussed further below. After conclusion of the fill time and once the thermistor resistance indicates approximately zero degrees centigrade (indicating the presence of water), the ice-maker 10 reverts to the home state 70a without further rotation of the gear 50.
Retelling now to
Referring now to
The LED 61 and the other switch 63 may be used, for example, to run other diagnostic tests, for example, initiating a fill cycle or a harvesting of ice. In addition the LEDs 61 may flash or change color to indicate various failure modes in an extremely compact user interface suitable for the difficult environments of the interior of a refrigerator.
Example constructions of the gear train 52 and of other elements and components of the ice harvest drive mechanism 14 are described in US patent application 2012/0186288 hereby incorporated in its entirety by reference.
Referring now to
The temperature sensor 90 may communicate by conductors 92 to a connector 94 having upwardly extending blades 96 that may be received within corresponding slots 98 in an end of the ice tray 12. The temperature sensor, conductors, and connector 94 may be held in position by a cover plate 99 stepping into the bottom of the ice tray 12.
The slots 98 in the ice tray 12 receiving the blades 96 may communicate with a socket 100, the latter mechanically and releasably interengaging with the drive coupling 16 to support the ice tray 12 for rotation by the coupling 16. When the drive coupling 16 is in the socket 100, the connector pins 55 electrically connect to the blades 96 thereby also providing an electrical as well as a mechanical connection between the drive coupling 16 and the ice tray 12.
Referring still to
Referring now to
In the fill position as shown in
With clockwise rotation of the drive coupling 16 carrying with it the conductive wipers 57 as the ice tray is moved to its flexing and discharging position, conductive wiper 57a will move off of the conductive portion of trace 58a indicating a movement from the home position. At an arbitrary angular motion, the conductive wiper 57a will contact a second portion of the outer trace 58a providing an eject signal 114 indicating that the tray is in the eject position to the microcontroller.
Referring now to
An upper surface of the upper panel 116 proximate to a wall 130 of the refrigerator may support upwardly extending tabs 132 for mounting the icemaker 10 against the wall 130. The tabs 132 may have rearwardly extending slots 134 to engage screws or shoulder screw's 136 projecting horizontally from the vertical face of the wall 130 as the icemaker 10 is moved rearward providing a simple installation of the icemaker 10 in a refrigerator from the front of the refrigerator. The slots 134 may have a constriction 136 allowing them to snap over the shaft of the screws 136 to prevent inadvertent dislodgment of the icemaker 10. The screws 136 may then be tightened further over the tabs 132.
Certain terminology is used herein for purposes of reference only, and thus is not intended to be limiting. For example, terms such as “upper”, “lower”, “above”, and “below” refer to directions in the drawings to which reference is made. Terms such as “front”, “back”, “rear”, “bottom” and “side”, describe the orientation of portions of the component within a consistent but arbitrary frame of reference which is made clear by reference to the text and the associated drawings describing the component under discussion. Such terminology may include the words specifically mentioned above, derivatives thereof, and words of similar import. Similarly, the terms “first”, “second” and other such numerical terms referring to structures do not imply a sequence or order unless clearly indicated by the context
The term “cube” should be understood to be an ice element not limited to any particular shape such as a cube. Generally, the invention contemplates at multiple different ice cube geometries may be used including cylinders, berth cylinders, hemispheres and the like.
When introducing elements or features of the present disclosure and the exemplary embodiments, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of such elements or features. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements or features other than those specifically noted. It is further to be understood that the method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.
It is specifically intended that the present invention not be limited to the embodiments and illustrations contained herein and the claims should be understood to include modified forms of those embodiments including portions of the embodiments and combinations of elements of different embodiments as, come within the scope of the following claims. All of the publications described herein, including patents and non-patent publications, are hereby incorporated herein by reference in their entireties
This application claims the benefit of U.S. provisional application 62/302,313 filed Mar. 2, 2016, and hereby incorporated by reference.
Filing Document | Filing Date | Country | Kind |
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PCT/US2017/014871 | 1/25/2017 | WO | 00 |
Number | Date | Country | |
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62302313 | Mar 2016 | US |