Patent ID: 12259167

Corresponding reference characters indicate corresponding parts throughout the drawings.

DETAILED DESCRIPTION

Referring toFIG.1, one embodiment of an ice maker is generally indicated at reference number10. This disclosure details exemplary features of the ice maker10that can be used individually or in combination to enhance ice making uniformity, ice harvesting performance, energy efficiency, assembly precision, and/or accessibility for repair or maintenance. One aspect of the present disclosure pertains to an evaporator assembly that includes an evaporator, a freeze plate, and a water distributor. As will be explained in further detail below, in one or more embodiments, the parts of the evaporator assembly are integrated together into a single unit. In certain embodiments, the water distributor includes a configuration of water distribution features that provides uniform water flow along the width of the freeze plate. In an exemplary embodiment, the water distributor is configured to provide ready access to the interior of the distributor for repair or maintenance. In one or more embodiments, the evaporator assembly is configured to mount the freeze plate within the ice maker in an orientation that reduces the time it takes to passively harvest ice using gravity and heat. Other aspects and features of the ice maker10will also be described hereinafter. Though this disclosure describes an ice maker that combines a number of different features, it will be understood that other ice makers can use any one or more of the features disclosed herein without departing from the scope of this disclosure.

The disclosure begins with an overview of the ice maker10, before providing a detailed description of an exemplary embodiment of an evaporator assembly.

I. Refrigeration System

ReferringFIG.1, a refrigeration system of the ice maker10includes a compressor12, a heat rejecting heat exchanger14, a refrigerant expansion device18for lowering the temperature and pressure of the refrigerant, an evaporator assembly20(broadly, an ice formation device), and a hot gas valve24. As shown, the heat rejecting heat exchanger14may comprise a condenser for condensing compressed refrigerant vapor discharged from the compressor12. In other embodiments, for example, in refrigeration systems that utilize carbon dioxide refrigerants where the heat of rejection is trans-critical, the heat rejecting heat exchanger is able to reject heat from the refrigerant without condensing the refrigerant. The illustrated evaporator assembly20integrates an evaporator21(e.g., serpentine refrigerant tubing), a freeze plate22, and a water distributor25into one unit, as will be described in further detail below. Hot gas valve24is used, in one or more embodiments, to direct warm refrigerant from the compressor15directly to the evaporator21to remove or harvest ice cubes from the freeze plate22when the ice has reached the desired thickness.

The refrigerant expansion device18can be of any suitable type, including a capillary tube, a thermostatic expansion valve or an electronic expansion valve. In certain embodiments, where the refrigerant expansion device18is a thermostatic expansion valve or an electronic expansion valve, the ice maker10may also include a temperature sensor26placed at the outlet of the evaporator tubing21to control the refrigerant expansion device18. In other embodiments, where the refrigerant expansion device18is an electronic expansion valve, the ice maker10may also include a pressure sensor (not shown) placed at the outlet of the evaporator tubing21to control the refrigerant expansion device19as is known in the art. In certain embodiments that utilize a gaseous cooling medium (e.g., air) to provide condenser cooling, a condenser fan15may be positioned to blow the gaseous cooling medium across the condenser14. A form of refrigerant cycles through these components via refrigerant lines28a,28b,28c,28d.

II. Water System

Referring still toFIG.1, a water system of the illustrated ice maker10includes a sump assembly60that comprises a water reservoir or sump70, a water pump62, a water line63, and a water level sensor64. The water system of the ice maker10further includes a water supply line (not shown) and a water inlet valve (not shown) for filling sump70with water from a water source (not shown). The illustrated water system further includes a discharge line78and a discharge valve79(e.g., purge valve, drain valve) disposed thereon for draining water from the sump70. The sump70may be positioned below the freeze plate22to catch water coming off of the freeze plate such that the water may be recirculated by the water pump62. The water line63fluidly connects the water pump62to the water distributor25. During an ice making cycle, the pump62is configured to pump water through the water line63and through the distributor25. As will be discussed in greater detail below, the distributor25includes water distribution features that distribute the water imparted through the distributor evenly across the front of the freeze plate22. In an exemplary embodiment, the water line63is arranged in such a way that at least some of the water can drain from the distributor through the water line and into the sump when ice is not being made.

In an exemplary embodiment, the water level sensor64comprises a remote air pressure sensor66. It will be understood, however that any type of water level sensor may be used in the ice maker10including, but not limited to, a float sensor, an acoustic sensor, or an electrical continuity sensor. The illustrated water level sensor64includes a fitting68that is configured to couple the sensor to the sump70(see alsoFIG.4). The fitting68is fluidly connected to a pneumatic tube69. The pneumatic tube69provides fluid communication between the fitting68and the air pressure sensor66. Water in the sump70traps air in the fitting68and compresses the air by an amount that varies with the level of the water in the sump. Thus, the water level in the sump70can be determined using the pressure detected by the air pressure sensor66. Additional details of exemplary embodiments of a water level sensor comprising a remote air pressure sensor are described in U.S. Patent Application Publication No. 2016/0054043, which is hereby incorporated by reference in its entirety.

In the illustrated embodiment, the sump assembly60further comprises a mounting plate72that is configured to operatively support both the water pump62and the water level sensor fitting68on the sump70. An exemplary embodiment of a mounting plate72is shown inFIG.4. The mounting plate72may define an integral sensor mount74for operatively mounting sensor fitting68on the sump70at a sensing position at which the water level sensor64is operative to detect the amount of water in the sump. The mounting plate72may also define a pump mount76for mounting the water pump62on the sump70for pumping water from the sump through the water line63and the distributor25. Each of the sensor mount74and the pump mount76may include locking features that facilitate releasably connecting the respective one of the water level sensor64and the water pump62to the sump70.

III. Controller

Referring again toFIG.1, the ice maker10may also include a controller80. The controller80may be located remote from the ice making device20and the sump70or may comprise one or more onboard processors, in one or more embodiments. The controller80may include a processor82for controlling the operation of the ice maker10including the various components of the refrigeration system and the water system. The processor82of the controller80may include a non-transitory processor-readable medium storing code representing instructions to cause the processor to perform a process. The processor82may be, for example, a commercially available microprocessor, an application-specific integrated circuit (ASIC) or a combination of ASICs, which are designed to achieve one or more specific functions, or enable one or more specific devices or applications. In certain embodiments, the controller80may be an analog or digital circuit, or a combination of multiple circuits. The controller80may also include one or more memory components (not shown) for storing data in a form retrievable by the controller. The controller80can store data in or retrieve data from the one or more memory components.

In various embodiments, the controller80may also comprise input/output (I/O) components (not shown) to communicate with and/or control the various components of ice maker10. In certain embodiments, for example, the controller80may receive inputs such as, for example, one or more indications, signals, messages, commands, data, and/or any other information, from the water level sensor64, a harvest sensor for determining when ice has been harvested (not shown), an electrical power source (not shown), an ice level sensor (not shown), and/or a variety of sensors and/or switches including, but not limited to, pressure transducers, temperature sensors, acoustic sensors, etc. In various embodiments, based on those inputs for example, the controller80may be able to control the compressor12, the condenser fan15, the refrigerant expansion device18, the hot gas valve24, the water inlet valve (not shown), the discharge valve79, and/or the water pump62, for example, by sending, one or more indications, signals, messages, commands, data, and/or any other information to such components.

IV. Enclosure/Ice Bin

Referring toFIG.2, one or more components of the ice maker10may be stored inside of an enclosure29of the ice maker10that defines an interior space. For example, portions or all of the refrigeration system and water system of the ice maker10described above can be received in the interior space of the enclosure29. In the illustrated embodiment, the enclosure29is mounted on top of an ice storage bin assembly30. The ice storage bin assembly30includes an ice storage bin31having an ice hole (not shown) through which ice produced by the ice maker10falls. The ice is then stored in a cavity36until retrieved. The ice storage bin31further includes an opening38which provides access to the cavity36and the ice stored therein. The cavity36, ice hole (not shown), and opening38are formed by a left wall33a, a right wall33b, a front wall34, a back wall35and a bottom wall (not shown). The walls of the ice storage bin31may be thermally insulated with various insulating materials including, but not limited to, fiberglass insulation or open- or closed-cell foam comprised, for example, of polystyrene or polyurethane, etc. in order to retard the melting of the ice stored in the ice storage bin31. A door40can be opened to provide access to the cavity36.

The illustrated enclosure29is comprised of a cabinet50(broadly, a stationary enclosure portion) and a door52(broadly, a movable or removable enclosure portion). InFIG.2, the door40of the ice storage bin assembly30is raised so that it partially obscures the ice maker door52. The door52is movable with respect to the cabinet50(e.g., on a hinge) to selectively provide access to the interior space of the ice maker10. Thus, a technician may open the door52to access the internal components of the ice maker10through a doorway (not shown; broadly, an access opening) as required for repair or maintenance. In one or more other embodiments, the door may be opened in other ways, such as by removing the door assembly from the cabinet.

V. Internal Support

Referring toFIGS.3-5, the illustrated ice maker10comprises a one-piece support110that is configured to support several components of the ice maker inside the enclosure29. For example, the illustrated support110is configured to support the sump70, the mounting plate72, and the evaporator assembly20at very precise positions to limit the possibility of misplacement of these components. The inventors have recognized that ice maker control schemes that use water level as a control input require accurate placement of the water level sensor in the sump. If the position of the water level sensor deviates from the specified position by even a small amount (e.g., millimeters or less), the control scheme can be disrupted. The inventors have further recognized that the aggregated dimensional tolerances of the parts of conventional assemblies for mounting internal ice maker components can lead to misplacement. Still further, the inventors have recognized that precisely positioning an evaporator assembly in an ice maker can enhance gravity-driven ice making and ice-harvesting performance.

In the illustrated embodiment, the support110includes a base112and a vertical support wall114. The illustrated vertical support wall comprises a first side wall portion116, a second side wall portion118, and a back wall portion120extending widthwise between the first and second side wall portions. A large opening122extends widthwise between the front end margins of the side wall portions116,118. When the ice maker10is fully assembled, this opening122is located adjacent a front doorway268(FIG.30) of the enclosure29such that a technician can access the components supported on the vertical wall through the opening when the door52is open.

Each side wall portion116,118includes an integral evaporator mount124(broadly, a freeze plate mount). The evaporator mounts124are configured to support the evaporator assembly20at an operative position in the ice maker10. Each side wall portion116,118further comprises an integral mounting plate mount126that is spaced apart below the evaporator mount124. The mounting plate mount126is configured to support the mounting plate72so that the mounting plate can mount the water level sensor fitting68and the pump62at operative positions in the ice maker10. An integral sump mount128for attaching the sump70to the ice maker is spaced apart below the mounting plate mount126of each side wall portion116,118. InFIGS.3-5, only the mounts124,126,128defined by the right side wall portion116are shown, but it will be understood that the left side wall portion118has substantially identical, mirror-image mounts in the illustrated embodiment.

At least one of the side wall portions116,118that defines the mounts124,126,128is formed from a single piece of monolithic material. For example, in one or more embodiments, the entire vertical support wall114is formed from a single monolithic piece of material. In the illustrated embodiment, the entire support110, including the base112and the vertical support wall114, is formed from a single piece of monolithic material. In one or more embodiments, the support110is a single molded piece. In the illustrated embodiment, the monolithic support110is formed by compression molding. Forming the support110from a single piece eliminates the stacking of tolerances that occurs in a multi-part support assembly and thereby increases the accuracy of the placement of the parts that are mounted on the support.

The evaporator mounts124are configured to mount the evaporator assembly20on the vertical support wall114in the enclosure29such that the freeze plate22slants forward. To accomplish this, each evaporator mount124in the illustrated embodiment comprises a lower connection point130and an upper connection point132forwardly spaced from the lower connection point. As shown inFIG.5, the connection points130,132are spaced apart along an imaginary line IL1that is oriented at a forwardly slanted angle α with respect to a plane BP the back wall portion120of the vertical support wall114. In use, the ice maker10is positioned so that the plane BP of the back wall portion120is substantially parallel to a plumb vertical axis VA. As such, the imaginary line IL1slants forward with respect to the plumb vertical axis VA at the angle α.

In the illustrated embodiment, each of the upper and lower connection points130,132comprises a screw hole. In use, the evaporator20is positioned between the side wall portions116,118, and a screw (not shown) is placed through each screw hole into a corresponding pre-formed screw hole associated with the evaporator assembly20. As explained below, the pre-formed evaporator screw-holes are arranged so that, when they are aligned with the evaporator mount screw holes130,132, the freeze plate22slants forward. It will be appreciated that an integral evaporator mount can include other types of connection points besides screw holes in one or more embodiments. For example, it is expressly contemplated that one or both of the screw holes130,132could be replaced by an integrally formed stud or other structure that can be used to register and attach a freeze plate to the support at the proper position.

Each mounting plate mount126comprises a pair of generally horizontally spaced tapered screw holes134(broadly, connection points). Similarly, each sump mount128comprises a pair of generally horizontally spaced mounting holes136(broadly, connection points). Again, the holes134,136of the mounting plate mount126and the sump mount128could be replaced with other types of integral connection points in one or more embodiments.

As shown inFIG.4, in one or more embodiments, the sump70is generally sized and arranged for being received in the space between the side wall portions116,118of the vertical support wall114. Each of a first end portion and a second end portion of the sump70that are spaced apart widthwise includes a pair of projections138at spaced apart locations. The projections138on each end portion of the sump70are configured to be received in the pair of mounting holes136defined by a respective one of the sump mounts128. The projections138, by being received in the mounting holes136, position the sump70at a precisely specified position along the height of the support110. In addition, a screw (not shown) is inserted through each mounting hole136and threaded into each projection138to fasten the sump70onto the support110at the specified position.

Like the sump70, the illustrated mounting plate72comprises a first end portion and a second end portion that are spaced apart widthwise. Each end portion of the mounting plate114defines a pair pre-formed screw holes that are configured to be aligned with the screw holes134of the corresponding mount126of the support110. Screws (broadly, mechanical fasteners; not shown) pass through the screw holes134and thread into the holes that are pre-formed in the mounting plate72to connect the mounting plate to the support110at a precisely specified position along the height of the support. In one or more embodiments, countersunk screws (e.g., screws with tapered heads) are used to connect the mounting plate72to the support110. The countersunk screws self-center in the tapered screw holes134.

It can be seen that the one-piece support110with integral mounts124,126,128can be used to ensure that the evaporator assembly20, the mounting plate72, and the sump70are supported in the ice maker10at the specified position. The support110can thereby position the freeze plate22to optimally balance desired performance characteristics, such as water distribution during ice making and ease/speed of ice-harvesting. Further, the support110can position the mounting plate72with respect to the sump70so that the pressure sensor fitting68mounted in the sensor mount74is precisely positioned with respect to the sump for accurately detecting the water level using the sensor64. Likewise, the support110positions the mounting plate72with respect to the sump70so that the pump62is precisely positioned for pumping water from the sump70through the ice maker10when the pump is mounted on the pump mount76.

VI. Freeze Plate

Referring toFIGS.6-8, an exemplary embodiment of the freeze plate22will now be described, before turning to other components of the evaporator assembly20that attach the freeze plate to the support110. The freeze plate22defines a plurality of molds150in which the ice maker10is configured to form ice. The freeze plate22has a front defining open front ends of the molds150, a back defining enclosed rear ends of the molds, a top portion and a bottom portion spaced apart along a height HF, and a right side portion (broadly, a first side portion) and a left side portion (broadly, a second side portion) spaced apart along a width WF.

Throughout this disclosure, when the terms “front,” “back,” “rear,” “forward,” “rearward,” and the like are used in reference to any part of the evaporator assembly20, the relative positions of the open front ends and enclosed rear ends of the freeze plate molds150provide a spatial frame of reference. For instance, the front of the freeze plate22that defines the open front ends of the molds150is spaced apart from the rear of the freeze plate in a forward direction FD (FIG.8), and the back of the freeze plate that extends along the enclosed rear ends of the molds is spaced apart from the front of the freeze plate in a rearward direction RD.

In the illustrated embodiment, the freeze plate22comprises a pan152having a back wall154that defines the back of the freeze plate. Suitably, the pan152is formed from thermally conductive material such as copper, optionally having one or more surfaces coated with a food-safe material. As is known in the art, the evaporator tubing21is thermally coupled to the back wall154of the freeze plate22for cooling the freeze plate during ice making cycles and warming the freeze plate during harvest cycles.

The pan152further comprises a perimeter wall156that extends forward from the back wall154. The perimeter wall156includes a top wall portion, a bottom wall portion, a right side wall portion (broadly, a first side wall portion), and a left side wall portion (broadly, a second side wall portion). The side wall portions of the perimeter wall156define the opposite sides of the freeze plate22, and the top and bottom wall portions of the perimeter wall define the top and bottom ends of the freeze plate. The perimeter wall156could be formed from one or more discrete pieces that are joined to the back wall154or the pan152, or the entire pan could be formed from a single monolithic piece of material in one or more embodiments. Suitably, the perimeter wall156is sealed to the back wall154so that water flowing down the freeze plate22does not leak through the back of the freeze plate.

A plurality of heightwise and widthwise divider plates160,162are secured to the pan to form a lattice of the ice cube molds150. In an exemplary embodiment, each heightwise divider plate160and each widthwise divider plate162is formed from a single piece of monolithic material. Each heightwise divider plate160has a right lateral side surface (broadly, a first lateral side surface) and a left lateral side surface (broadly a second lateral side surface) oriented parallel to the right lateral side surface. Each widthwise divider plate162has a bottom surface and a top surface oriented parallel to the bottom surface. The heightwise divider plates162extend from lower ends that are sealingly connected to the bottom wall portion of the perimeter wall156to upper ends that are sealingly connected to the top wall portion of the perimeter wall. The plurality of widthwise divider plates160similarly extend from first ends sealingly connected to the right side wall portion of the perimeter wall156to second ends sealingly connected to the left side wall portion of the perimeter wall.

Generally, the heightwise divider plates160and the widthwise divider plates162are interconnected in such a way as to define a plurality of ice molds150within the perimeter wall156. For example, in the illustrated embodiment, each of the heightwise divider plates160has a plurality of vertically-spaced, forwardly-opening slots164; each of the widthwise diver plates has a plurality of horizontally-spaced, rearwardly-opening slots166; and the heightwise and widthwise divider plates are interlocked at the slots164,166to form the lattice. Suitably, each widthwise divider plate162defines a plurality of the molds150(e.g., at least three molds) immediately above the divider plate and a plurality of the molds (e.g., at least three molds) immediately below the divider plate. Each heightwise divider plate160likewise defines a plurality of the molds150(e.g., at least three molds) immediately to one lateral side of the divider plate and a plurality of the molds (e.g., at least three molds) immediately to the opposite lateral side of the divider plate.

Each of the divider plates160,162has a front edge and a back edge. The back edges may suitably be sealingly joined to the back wall154of the freeze plate pan152. When the freeze plate22is assembled, the front edges of some or all of the divider plates160,162(e.g., at least the widthwise divider plates) lie substantially on a front plane FP (FIG.8) of the freeze plate22. In one or more embodiments, the front plane FP is parallel to the back wall154.

A plurality of the ice molds150formed in the freeze plate22are interior ice molds having perimeters defined substantially entirely by the heightwise and widthwise divider plates160,162. Others of the molds150are perimeter molds having portions of their perimeters formed by the perimeter wall156of the freeze plate pan152. Each interior ice mold150has an upper end defined substantially entirely by the bottom surface of one of the widthwise divider plates162and a lower end defined substantially entirely by the top surface of an adjacent one of the widthwise divider plates. In addition, each interior mold150has a left lateral side defined substantially entirely by a right lateral side surface of a heightwise divider plate162and a right lateral side defined substantially entirely by a left lateral side surface of the adjacent heightwise divider plate.

As shown inFIG.8, each widthwise divider plate162slopes downward and forward from the back wall154of the freeze plate22such that an included angle β between an upper surface of each widthwise divider plate and the back wall is greater than 90°. In one or more embodiments, the included angle β is at least 100° and less than 180°. It can be seen that the included angle between the top surface of each widthwise divider plate16and the front plane FP is substantially equal to the included angle β. Further, it can be seen that the included angle between the bottom surface of each horizontal divider plate162and the back wall154(and also the included angle between the bottom surface of each horizontal divider plate162and the front plane FP) is substantially equal to 180° minus β. The top and bottom portions of the perimeter wall156of the pan are oriented substantially parallel to the widthwise divider plates162in one or more embodiments.

A series of threaded studs168extend outward from the perimeter wall156at spaced apart locations around the perimeter of the freeze plate22. As will be explained in further detail below, the threaded studs168are used to secure the freeze plate22to an evaporator housing170that attaches the evaporator assembly20to the support110. The studs168are suitably shaped and arranged to connect the freeze plate22to the evaporator housing170, and further to the support110, such that the back wall154and front plane FP of the freeze plate slants forward when the freeze plate is installed in the ice maker10.

VII. Evaporator Housing

Referring toFIGS.9-14, the evaporator housing170will now be described in greater detail. In general, the evaporator housing170is configured to support the evaporator tubing21and the freeze plate22. As will be explained in further detail below, the water distributor25is integrated directly into (i.e., forms a part of) the evaporator housing170. The evaporator housing170comprises a frame including a bottom piece172, a top piece174, and first and second side pieces176that together extend around the perimeter of the freeze plate22. Each of the bottom piece172, the top piece174, and the opposite side pieces176is formed from a single, monolithic piece of material (e.g., molded plastic), in one or more embodiments. The inner surfaces of the bottom piece172, the top piece174, and the opposite side pieces176may include a gasket (not shown) to aid in watertight sealing of the evaporator housing. The top piece174of the evaporator housing170forms a bottom piece (broadly, a first piece) of the two-piece distributor25in the illustrated embodiment.

A back wall178is supported on the assembled frame pieces172,174,176,178in spaced apart relationship with the back wall154of the freeze plate22. As shown inFIG.14, the evaporator housing170defines an enclosed space180between the back wall154of the freeze plate22and the back wall178of the housing. As explained in U.S. Patent Application Publication No. 2018/0142932, which is hereby incorporated by reference in its entirety, in one or more embodiments, two discrete layers182,184of insulation fills enclosed space176and thoroughly insulates the evaporator tubing21.

The bottom piece172, the top piece174, the opposite side pieces176, and/or the back wall178may have features that facilitate assembling them together to form the evaporator housing170in a variety of ways, including snap-fit features, bolts and nuts, etc. For example, each of the frame pieces172,174,176comprises stud openings186that are arranged to receive the studs168on the corresponding wall portion of the perimeter wall156of the freeze plate22. Some of the stud holes186are visible inFIG.12. In one or more embodiments, the back wall178is joined to the assembled frame pieces172,174,176by ultrasonic welding.

Referring toFIGS.15and16, one example of how the housing pieces172,174,176attach to the freeze plate72is shown in greater detail. Specifically, the top housing piece174is shown, but it will be understood that the other housing pieces may attach to the freeze plate in a like manner. The top piece174includes a front section that defines the stud openings186. In the illustrated embodiment, each stud opening186comprises a countersunk screw recess that includes an annular shoulder192. The top piece174is positioned atop the freeze plate22such that one stud168is received in each of the openings186. In the illustrated embodiment, a gasket194is located between the top of the freeze plate22and the bottom of the top piece174to seal the interface between the two parts. Nuts196are tightened onto each of the studs168to attach the top piece174to the freeze plate22. Further, because the housing top piece174forms the bottom piece of the distributor25, tightening the nuts196onto the studs also attaches the distributor directly to the freeze plate in the illustrated embodiment. Each nut196is tightened against the shoulder192of a respective countersunk recesses186(broadly, the nuts are tightened directly against the top housing piece170or bottom distributor piece). In the illustrated embodiment, caps198are placed over the tops of the countersunk recesses186. Suitably, the tops of the caps198are substantially flush with the surface of the piece174to present a smooth surface to water flowing through the distributor25.

VIII. Mounting of Evaporator Assembly so that Freeze Plate Slants Forward

Referring again toFIGS.9and10, each of the side pieces176of the evaporator housing170include pre-formed lower and upper screw openings200,202at vertically spaced apart locations. The upper and lower screw openings200,202are configured to be positioned in registration with the screw openings130,132of a respective side wall portion116,118of the support110. When each side piece176is secured to the freeze plate22via the studs168, the screw openings200,202are spaced apart along an imaginary line IL2oriented substantially parallel to the back wall154and the front plane FP of the freeze plate22. Referring toFIG.17, when screws (not shown) secure the evaporator assembly20to the support110via the aligned lower screw openings130,200and the aligned upper screw openings132,202, the imaginary line IL2of the evaporator housing170is aligned with the forwardly slanted imaginary line IL1of the support.

Thus, the screw openings130,132,200,202position the freeze plate22on the support110so that the back wall154and front plane FP are oriented at the forwardly slanted angle α with respect to both the plumb vertical axis VA and the back plane BP of the support110. In one or more embodiments, the included angle α between the back wall154/front plane FP and the plumb vertical axis VA/back plane BP is at least about 1.5°. For example, in an exemplary embodiment, the included angle α is about 2.0°. Accordingly, the illustrated ice maker10is configured to mount the freeze plate22in the enclosure29so that the back wall154slants forward. It will be appreciated that, though the one-piece support110and the side pieces176of the evaporator housing170are used to mount the freeze plate22in the slanted orientation in the illustrated embodiment, other ways of mounting a freeze plate may be used in other embodiments.

It is believed that conventional wisdom in the field of ice makers held that orienting a freeze plate with grid-type divider plates so that the back wall of the freeze plate slants forward would adversely affect the water distribution performance of the ice maker. However, because of the high-quality flow distribution produced by the water distributor25—achieved, for example, using one or more of the water distribution features described below—water is effectively distributed to the molds150even though the freeze plate22is mounted with the back wall154slanted forward. Further, the slanted freeze plate22enables the ice maker10to harvest ice quickly, using gravitational forces. In one or more embodiments, the ice maker10is configured to execute a harvest cycle by which ice is released from the molds150of the freeze plate22, wherein substantially the only forces imparted on the ice during the harvest cycle are gravitational forces. For example, the harvest cycle is executed by actuating the hot gas valve24to redirect hot refrigerant gas back to the evaporator tubing21, thereby warming the freeze plate22. The ice in the molds150begins to melt and slides forward down the sloping widthwise divider plates162, off the freeze plate, and into the ice bin30. In a harvest cycle in which substantially the only forces imparted on the ice are gravitational forces, no mechanical actuators, pressurized air jets, or the like are used to forcibly push the ice off of the freeze plate22. Rather, the slightly melted ice falls by gravity off of the freeze plate22.

IX. Water Distributor

Referring now toFIGS.9and18-19, an exemplary embodiment of the distributor25will now be described. As explained above, the distributor comprises a bottom piece174that forms a top piece of the evaporator housing170. The distributor25further comprises a top piece210that releasably attaches to the bottom piece174to form the distributor. While the illustrated distributor25comprises a two-piece distributor that is integrated directly into the evaporator housing170, it will be understood that distributors can be formed from other numbers of pieces and attach to the ice maker in other ways in other embodiments. As shown inFIG.9, the distributor25is mounted on the evaporator assembly20adjacent the top of the freeze plate22and has a width WD that extends generally along the width WF of the freeze plate22. The distributor25extends widthwise from a right end portion (broadly, first end portion) adjacent the right side of the freeze plate22to a left end portion (broadly, a second end portion) adjacent the left side of the freeze plate.

The distributor25has a rear, upstream end portion defining an inlet212and a front, downstream end portion defining an outlet214. The downstream end portion extends widthwise adjacent the top-front corner of the freeze plate22, and the upstream end portion extends widthwise at location spaced apart rearward from the downstream end portion. In the illustrated embodiment, the inlet212formed by an opening at the upstream end portion of the distributor, and the outlet214is defined by an exposed lower front edge of the distributor25. In use, this edge is arranged so that water flows off of the edge onto the top portion of the freeze plate22. It is contemplated that the inlet and/or outlet could have other configurations in other embodiments.

As shown inFIG.20, the distributor25defines a distributor flow path FP extending generally forward from the inlet212to the outlet214. The distributor25is generally configured to direct water imparted through the distributor along the distributor flow path FP to discharge the water from the outlet214such that the water flows from the top portion of the freeze plate22to the bottom portion generally uniformly along the width WF of the freeze plate. As will be explained in further detail below, the distributor25includes a number of water distribution features that direct the water flowing along the flow path FP to be distributed generally uniformly along substantially the entire width of the distributor.

Each of the bottom and top pieces174,210will now be described in detail before describing how the distributor25is assembled and used to distribute water over the freeze plate22.

IX.A. Distributor Bottom Piece

Referring toFIGS.21-22, the bottom distributor piece174has a right end wall216(broadly, a first end wall) at the right end portion of the distributor25, a left end wall218(broadly, a second end wall) at the left end portion of the distributor, and a bottom wall220extending widthwise from the right end wall to the left end wall. Referring toFIG.23, as explained above, the bottom distributor piece174is directly attached to the freeze plate22. Further, in the illustrated embodiment, the bottom distributor piece174is in direct contact with the insulation184that fills the enclosed space180between the back wall154of the freeze plate and the back wall178of the evaporator housing170. A front section222of the bottom wall220is located generally above the freeze plate22to mount the distributor piece174on the freeze plate as described above, and a rear section224of the bottom wall is located generally above the enclosed space180to directly contact the insulation184.

In the illustrated embodiment, the rear section224includes a rear leg226extending downward at a rear end portion of the bottom wall and a front leg228extending downward at a location forwardly spaced from the rear leg. Each of the front and rear legs226,224extends widthwise between the right and left end walls216,218of the bottom distributor piece174. The rear leg226is sealingly engaged with the back wall178of the evaporator housing170(e.g., the rear leg is ultrasonically welded to the back wall). The bottom wall220defines a lower recess230located between the front and rear legs226,228. The lower recess230extends widthwise between the right and left end walls216,218and forms the top of the enclosed space180. Thus a portion of the insulation184is received in the recess230and directly contacts the bottom distributor piece along three sides defining the recess. This is thought to thermal losses between the distributor and evaporator.

Referring toFIG.24, each end wall216,218in the illustrated embodiment comprises an elongate tongue232formed along an inner surface. Only the left end wall218is shown inFIG.24, but it will be understood that the right end wall216has a substantially identical, mirror image tongue232. The elongate tongues232extend longitudinally in parallel, generally front-to-back directions. The elongate tongues232are generally configured to form male fittings that releasably couple the bottom distributor piece174to the top distributor piece210without the use of separate fasteners. Each elongate tongue232has a front end portion and a rear end portion spaced apart longitudinally from the front end portion. Between the front end portion and the rear end portion, each tongue comprises a slight depression234.

Referring toFIGS.19and20, the bottom wall220extends generally forward from a rear, upstream end portion to a front, downstream end portion. A rear wall236extends upward from the upstream end portion of the bottom wall220. The inlet opening212is formed in the rear wall236. In the illustrated embodiment, the inlet opening236is generally centered on the rear wall236at a spaced apart location between the end walls216,218. Thus, broadly speaking, the inlet opening212through which water is directed into the interior of the distributor25is spaced apart widthwise between the first end portion and the second end portion of the distributor. During use, the distributor25is configured to direct the water to flow from the inlet opening212along the bottom wall220in a generally forward direction FD from the upstream end portion of the bottom wall to the downstream end portion.

An integral inlet tube238protrudes rearward from the rear wall236and fluidly communicates through the rear wall via the inlet opening212. The tube238slopes downward and rearward as it extends away from the rear wall236. The inlet tube238is configured to be coupled to the ice maker's water line63(FIG.1). Accordingly, when ice is being made, the pump62pumps water from the sump70through the water line63and into the distributor25via the integral inlet tube238. When ice is not being made, residual water in the distributor25can drain through the inlet tube238, down the water line63, and into the sump70.

In the illustrated embodiment, the rear section224of the bottom wall220slopes downward and rearward along substantially the entire width of the bottom wall. Conversely, the front section222of the bottom wall220slopes downward and forward along substantially the entire width. The front section222thus forms a runoff section along which water flows forward and downward toward the downstream end portion of the bottom wall220. Between the sloping rear section224and the sloping front section222the bottom wall comprises a middle section that includes a widthwise groove240. The widthwise groove is configured to sealingly receive a portion of the top distributor piece210when the top distributor piece is coupled to the bottom distributor piece174. In one or more embodiments, the groove240is convex in the widthwise direction (seeFIG.33). An apex of the bottom wall220is located immediately upstream of the widthwise groove240. The rear section224of the bottom wall slopes downward from the apex to the rear wall236. As shown inFIG.23, the rear section224of the bottom wall220includes a ramp surface242that defines the apex and a rearmost (or upstream-most) surface portion244(broadly, an upstream segment). The ramp surface242and the rearmost surface portion244extend widthwise from the right end wall216to the left end wall218. The ramp surface242slopes upward in the generally forward direction and downward in the generally rearward direction. The rearmost surface portion244slopes upward in the generally forward direction more gradually than the ramp surface242. The rearmost surface portion244is oriented at an angle of less than 180° with respect to the ramp surface242such that the rearmost surface portion slopes downward in the generally rearward direction at a more gradual angle than the ramp surface in the illustrated embodiment.

The bottom wall220is configured to passively drain water from the distributor25when the ice maker10stops making ice. Whenever the ice maker10stops making ice, residual water in the front portion of the distributor25flows forward along the sloping front section222(runoff section) of the bottom wall220and drains off of the outlet214onto the freeze plate22. Similarly, residual water in the rear portion of the distributor25flows rearward along the sloping rear section224and drains through the inlet opening212into the inlet tube238. The water directed forward flows downward along freeze plate22and then flows off the freeze plate into the sump70. The water directed rearward flows downward through the water line63into the sump70. Thus, the distributor25is configured to direct substantially all residual water into the sump70when the ice maker10is not making ice. Further, in one or more embodiments, the sump70is configured to drain substantially all of the water received therein through the discharge line78when the ice maker10is not in use. As can be seen, the shape of the bottom wall220of the distributor25facilitates total passive draining of the ice maker10when ice is not being made.

Referring toFIG.21, a lateral diverter wall246extends upward from the bottom wall220along the rearmost surface portion244. The lateral diverter wall246is spaced apart between the rear wall236and the ramp surface242. The lateral diverter wall246extends upward from the bottom wall220to a top edge that is spaced apart below the top of the assembled distributor25(seeFIG.20). The diverter wall246extends widthwise from a right end portion (broadly, a first end portion) spaced apart from the right end wall216to a left end portion (broadly, a second end portion) spaced apart from the left end wall216. The lateral diverter wall246is positioned in front of the inlet opening214. As water flows into the distributor25through the inlet opening, the lateral diverter wall246is configured to divert at least some of the water laterally outward, forcing the water to flow around the left and right ends of the lateral diverter wall.

Referring toFIGS.20A and23, the downstream end portion of the bottom wall220defines a downwardly curving surface tension curve247that extends widthwise from the right end wall216to the left end wall218. The downwardly curving surface tension curve247is configured so that surface tension causes the water flowing along the bottom wall220to adhere to the curve and be directed downward by the curve toward the top end portion of the freeze plate22. In one or more embodiments, the surface tension curve270is at least partially defined by a radius R of at least 1 mm. In certain embodiments, the surface tension curve270is defined by a radius of less than 10 mm. In one or more embodiments, the surface tension curve270is defined by a radius in an inclusive range of from 1 mm to 3 mm. In an exemplary embodiment, the surface tension curve270is defined by a radius of 1.5 mm.

The bottom wall220further comprises a waterfall surface249extending generally downward from the surface tension curve274to a bottom edge that defines the outlet214of the distributor212. The waterfall surface249extends widthwise from the right end wall216to the left end wall218. The waterfall surface249generally is configured so that surface tension causes the water imparted through the distributor25to adhere to the waterfall surface and flow downward along the waterfall surface onto the top end portion of the freeze plate22. In one or more embodiments, the waterfall surface249slants forward in the ice maker10such that the waterfall surface is oriented generally parallel to the back wall254(and front plane FP) of the forwardly slanting freeze plate22.

IX.B. Top Distributor Piece

Referring toFIGS.25-27, the top distributor piece210has a right end wall250(broadly, a first end wall) at the right end portion of the distributor25and a left end wall252(broadly, a second end wall) at the left end portion of the distributor. The width of the top distributor piece210is slightly less than the width of the bottom distributor piece174such that the top distributor piece is configured to nest between the end walls216,218of the bottom distributor piece.

Referring toFIG.28, each end wall250,252in the illustrated embodiment comprises an elongate groove254along an outer surface. Only the left end wall252is shown inFIG.28, but it will be understood that the right end wall250has a substantially identical, mirror image groove254. Generally, the elongate grooves254are configured to form complementary female fittings that mate with the male fittings formed by the elongate tongues232to releasably couple the top distributor piece210to the bottom distributor piece174without the use of separate fasteners. The elongate grooves254are generally parallel, extending longitudinally in a generally front-to back direction. The rear end portion of each elongate groove254defines a flared opening through which a respective elongate tongue174can pass into the groove. Each end wall further defines a protuberance256that protrudes into the groove at a location spaced apart between the front and rear ends of the groove254.

Referring again toFIGS.25-27, the top distributor piece210comprises a top wall258that extends widthwise from the right end wall250to the left end wall252. The top wall258extends generally forward from a rear edge margin. A front wall260extends generally downward from a front end portion of the top wall to a free bottom edge margin. Two handle portions262extend forward from the front wall260in the illustrated embodiment.

As shown inFIGS.26-27, the top distributor piece210further comprises a weir264that extends downward from the top wall258at a location spaced apart between the rear edge margin and the front wall260. The weir264extends widthwise from the right end wall250to the left end wall252and has a free bottom edge margin that is configured to be received in the widthwise groove240of the bottom distributor piece174. As shown inFIG.27, the bottom edge margin of the weir264is convex in the widthwise direction. The weir264defines a plurality of openings266at spaced apart locations along the width WD of the distributor25. A bottom portion of the weir264below the openings266is configured to hold back water until the water level reaches the bottom of the openings. The openings266are configured so that water is passable through the openings as it is imparted through the distributor25. Adjacent openings are separated by portions of the weir264, such that the weir is configured to form a segmented weir that allows water to cross at spaced apart segments along the width WD of the distributor25(through the openings).

IX.C. Assembly of Two-Piece Distributor

Referring toFIGS.29-30, to assemble the distributor25, the top distributor piece210is aligned in the widthwise direction with the space between the end walls216,218of the bottom distributor piece174. Then the top piece210is moved in the rearward direction RD into the space between the rear walls216,218, such that the elongate tongues232of the bottom piece are slidably received in the elongate grooves254of the top piece.

As seen inFIG.30, the evaporator assembly20is suitably arranged in the interior of the ice maker enclosure29so that the top piece210can be installed/removed through an access opening268such as the doorway of the cabinet50. In the illustrated embodiment, the doorway268is spaced apart from the front of the evaporator assembly20in the forward direction FD. Further, the front opening122in the support110is located between the front of the evaporator assembly20and the doorway268. Thus, the top distributor piece210can be installed by moving the piece through the doorway268and the opening122in the rearward direction RD. The top distributor piece210is removed by moving the piece through the opening122and the doorway268in the forward direction FD.

Each tongue232is configured to be slidably received in the respective groove254as the top distributor piece210moves toward the bottom distributor piece174in the rearward direction RD. That is, the parallel longitudinal orientations of the tongues232and grooves254facilitate coupling the top distributor piece210to the bottom distributor piece174simply by moving the top distributor piece in the rearward direction RD. Thus, the complementary fittings formed by the tongues232and grooves254are configured to be engaged by movement of the top distributor piece210inward into the interior of the enclosure29from the doorway268. Further, the complementary fittings232,254are configured to be disengaged simply by urging the top distributor piece210away from the bottom distributor piece174in the forward direction FD, toward the doorway268. When maintenance or repair of the distributor25is required, a technician merely opens the door52(FIG.2), grips the handles262, and pulls the top distributor piece210outward in the forward direction FD through the doorway268. To replace the top distributor piece210, the technician inserts the piece through the doorway268, aligns the open ends of the grooves254with the tongues232, and pushes the top piece rearward. The tongues232are then slidably received in the grooves254, and the complementary fittings thereby couple the top distributor piece210to the bottom distributor piece174without using any additional fasters such as screws or rivets.

Though the illustrated embodiment uses the bottom distributor piece's elongate tongues232as male fittings and the top distributor piece's elongate grooves254as complementary female fittings, other forms or arrangements of complementary integral fittings can be utilized to releasably couple one distributor piece to another in one or more embodiments. For example, it is expressly contemplated that in certain embodiments one or more male fittings could be formed on the top distributor piece and one or more complementary female fittings could be formed on the bottom distributor piece. It is further contemplated that the fittings could be formed at alternative or additional locations other than the end portions of the distributor.

Referring toFIG.31, each pair of complementary fittings comprises a detent configured to keep the respective tongue232at a coupling position along the respective groove254. More specifically, the protuberances256formed in the grooves254are configured to be received in the depressions234of the tongues232to provide a detent when the complementary fittings are at the coupling position. The detent resists inadvertent removal of the top distributor piece210from the bottom distributor piece174and provides a tactile snap when the tongue232slides along the groove254to the coupling position. It will be appreciated that the detent can be formed in other ways in one or more embodiments.

Referring toFIGS.20and32, as the top distributor piece210slides in the rearward direction RD to couple the distributor pieces together, the bottom edge margin of the weir264slides along the downstream (front) section222of the bottom wall220. When the top distributor piece210reaches the coupling position, the bottom edge margin of the weir264is received in the groove240. In one or more embodiments, placing the weir264in the groove240requires pushing the top piece210rearward past a slight interference with the bottom piece174. When the bottom edge margin of the weir264is received in the groove240, the weir sealingly engages the bottom wall220such that water flowing along the distributor flow path FP is inhibited from flowing through an interface between the bottom edge margin of the weir and the bottom wall and is instead directed to flow across the weir through the plurality of openings266.

The weir264extends widthwise along a middle section of the assembled distributor25, at a location spaced apart between the front wall260and the rear wall236. The only couplings between the top distributor piece210and the bottom distributor piece174at this middle section of the distributor25are the tongue-and-groove connections at the left and right end portions of the distributor. Thus, in the illustrated embodiment, the middle section of the distributor25includes couplings at the first and second end portions of the distributor that restrain upward movement of the top distributor piece210with respect to the bottom distributor piece174, but the distributor is substantially free of restraints against upward movement of the top distributor piece relative the bottom distributor piece along the middle section of the distributor at locations between these couplings. However, because the bottom edge margin of the weir264is convex and the groove240is correspondingly concave in the widthwise direction (FIG.32), even as the distributor pieces174,210flex and deform during use, the seal between the weir and the bottom wall220is maintained and water is reliably directed to flow through of openings266, instead of downward through the interface between the weir and the bottom wall.

IX.D. Water Flow Through Distributor

Referring toFIG.20, the distributor25is configured to direct water to flow from the inlet212to the outlet214such that the water flows along the flow path FP between the bottom and top walls220,258and then is directed downward along the surface tension curve247and the water fall surface249onto the top portion of the freeze plate22. Initially, the water flows generally in the forward direction from the inlet tube238through the inlet opening212in the rear wall236. The water then encounters the lateral diverter wall246. The lateral diverter wall246diverts at least some of the water laterally outward, such that the water continues forward through the widthwise gaps between the end portions of the lateral diverter wall and the end portions of the distributor25.

After flowing past the lateral diverter wall246, the water encounters the ramp surface242and the segmented weir264. The ramp surface242is immediately upstream of the weir264such that the water flowing along the bottom wall220of the distributor25must flow upward along the ramp surface before flowing across the weir. The weir264is configured so that the openings266are spaced apart above the bottom wall220(e.g., the bottom edges of the openings are spaced apart above the apex of the ramp surface242). Thus, in the illustrated embodiment, the water must flow upward along the ramp surface242, and upward along a portion of the height of the weir264before it can flow through the openings266across the weir. In one or more embodiments, the weir264is configured so that the portion of the distributor25upstream of the weir backfills with water to a level that generally corresponds with the height of the bottom edges of the openings266before the water begins to spill over the weir through the openings. In certain embodiments, the ramp surface242can direct at least some of the water flowing in the forward direction FD along the ramp surface to flow through the openings266before the upstream portion of the distributor25fills with water to a level that corresponds with the height of the bottom edges of the openings. After flowing across the weir264, the water drops downward onto the sloped front runoff section222of the bottom wall220and then flows downward and forward.

As can be seen, the upper rear edge of the front runoff section222is spaced apart below the openings266by a substantially greater distance than the apex of the ramp surface242. Thus, the water falls a relatively great distance from the segmented weir264onto the front runoff section222, which may create turbulence on impact, enhancing the distribution of water in the distributor25. In one or more embodiments, the vertical distance between the bottom edges of the openings266and the upper rear edge of the front runoff section222is at least 5 mm; e.g., at least 7 mm, e.g., at least 10 mm; e.g., about 12 to 13 mm.

Referring toFIG.20A, in the assembled distributor25, the front wall260of the top distributor piece210forms an overhanging front wall that overhangs the bottom wall220. The bottom edge margin of the front wall260is spaced apart above the forwardly/downwardly sloping front runoff section222of the bottom wall220such that a flow restriction270is defined between the runoff section and the overhanging front wall. The flow restriction270comprises a gap (e.g., a continuous gap) that extends widthwise between the first end portion and the second end portion of the distributor25. In general, the flow restriction270is configured to restrict a rate at which water flows through the flow restriction toward the outlet214. In one or more embodiments, the flow restriction270has a height extending vertically from the runoff section222to the bottom of the front wall260of less than 10 mm, e.g., less than 7 mm; e.g., less than 5 mm; e.g., about 2 to 3 mm.

The water flowing forward along the front section222reaches the flow restriction270, and the flow restriction arrests or slows the flow of water. In one or more embodiments, the overhanging front wall260acts as a kind of inverted weir. The flow restriction270slows the flow of water to a point at which water begins to slightly backfill the front portion of the distributor25. This creates a small reservoir of water behind the flow restriction270. A metered amount of water flows continuously from this back-filled reservoir through the flow restriction270along substantially the entire width WD of the distributor25.

The surface tension curve247—and more broadly the downstream end portion of the bottom wall220—is forwardly proud of the overhanging front wall260and the flow restriction270. After the water flows (e.g., is metered) through the flow restriction270, the water adheres to the downwardly curving surface tension curve247as it flows generally forward. The surface tension curve247directs the water downward onto the waterfall surface249. The water adheres to the waterfall surface249and flows downward along it. Finally the water is discharged from the outlet edge214of the waterfall surface249onto the top end portion of the freeze plate22.

Because of water distribution features such as one or more of the lateral diverter wall246, the ramp surface242, the segmented weir264, the flow restriction270, the surface tension curve247, and the waterfall surface249, water is discharged from the outlet214at a substantially uniform flow rate along the width WD of the distributor25. The distributor25thus directs water imparted through the distributor to flow downward along the front of the freeze plate22generally uniformly along the width WF of the freeze plate during an ice making cycle. Moreover, the distributor25controls the dynamics of the flowing water so that the water generally adheres to the surfaces of the front of the freeze plate22as it flows downward. Thus, the distributor25enables ice to form at a generally uniform rate along the height HF and width WF of the freeze plate22.

X. Use

Referring again toFIG.1, during use the ice maker10alternates between ice making cycles and harvest cycles. During each ice making cycle, the refrigeration system is operated to cool the freeze plate22. At the same time, the pump62imparts water from the sump70through the water line63and further through the distributor25. The distributor25distributes water along the top portion of the freeze plate22which freezes into ice in the molds150at a generally uniform rate along the height HF and width WF of the freeze plate22. When the ice reaches a thickness that is suitable for harvesting, the pump62is turned off and the hot gas valve24redirects hot refrigerant gas to the evaporator tubing21. The hot gas warms the freeze plate22, causing the ice to melt. The melting ice falls by gravity from the forwardly slanted freeze plate22into the bin30. When harvest is complete, the pump62can be reactivated to begin a new ice making cycle. But if additional ice is not required, the discharge valve79is opened. Residual water in the distributor25drains into the sump70as described above, and the water from the sump drains through the discharge line78. The discharge valve79can be closed when the water level sensor64detects that the sump70is empty. If repair or maintenance of the distributor25should ever be required, a technician can simply open the door52to the enclosure and pull out the top piece210as described above. No fasteners are used when removing and replacing the top distributor piece210.

When introducing elements of the present invention or the preferred embodiment(s) thereof, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of the elements. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As various changes could be made in the above products and methods without departing from the scope of the invention, it is intended that all matter contained in the above description shall be interpreted as illustrative and not in a limiting sense.