Refrigerator appliance and a method for operating a refrigerator appliance

A refrigerator appliance is provided. The refrigerator appliance includes features for increasing humidity of an atmosphere about the refrigerator appliance. A method for operating a refrigerator appliance is also provided. The method includes measuring a relative humidity of air about the refrigerator appliance and operating a humidifier of the refrigerator appliance if the relative humidity of air about the refrigerator appliance is less than a reference value.

FIELD OF THE INVENTION

The present subject matter relates generally to refrigerator appliances.

BACKGROUND OF THE INVENTION

Dry air or low humidity conditions, such as conditions where the relative humidity is less than thirty percent, can have various unpleasant effects. For example, low humidity conditions can cause health related issues, such as itchy eyes, sore throat and cracked skin. Dry air also facilitates static electricity accumulation that can cause painful shocks and damage computers or other electronic equipment. In addition, hardwood floors lose moisture and contract in low humidity conditions. House plants can also suffer in low humidity conditions, and wallpaper can peel away from walls in dry air.

Humidifiers include features for evaporating liquid water in order to increase an ambient humidity around the humidifiers. By increasing the ambient humidity, humidifiers can assist with alleviating the unpleasant effects associated with dry air and low humidity conditions. However, humidifiers generally suffer from certain drawbacks. For example, a user of a humidifier may have to frequently refill the humidifier with fresh water. Such refilling can be tedious and inconvenient. In addition, humidifiers can cumbersome and consume large amounts of valuable floor space within a room. Humidifiers can also be expensive to purchase and/or operate.

Accordingly, an appliance with features for increasing an ambient humidity about the appliance would be useful. For example, a refrigerator appliance with features for increasing an ambient humidity about the refrigerator appliance would be useful. In particular, a refrigerator appliance that does not require a user of the refrigerator appliance to manually add fresh water to the refrigerator appliance in order to increase an ambient humidity about the refrigerator appliance would be useful.

BRIEF DESCRIPTION OF THE INVENTION

The present subject matter provides a refrigerator appliance. The refrigerator appliance includes features for increasing humidity of an atmosphere about the refrigerator appliance. A method for operating a refrigerator appliance is also provided. The method includes measuring a relative humidity of air about the refrigerator appliance and operating a humidifier of the refrigerator appliance if the relative humidity of air about the refrigerator appliance is less than a reference value. Additional aspects and advantages of the invention will be set forth in part in the following description, or may be apparent from the description, or may be learned through practice of the invention.

In a first exemplary embodiment, a refrigerator appliance is provided. The refrigerator appliance includes a cabinet that defines a chilled chamber. The cabinet also defines a mechanical compartment at a bottom portion of the cabinet. A sealed system is charged with a refrigerant and is configured for generating chilled air within the chilled chamber of the cabinet. The sealed system includes a condenser positioned within the mechanical compartment of the cabinet. An evaporation pan is positioned below the condenser of the sealed system within the mechanical compartment of the cabinet. An air handler is positioned adjacent the condenser of the sealed system. The air handler is operable to urge a flow of air across the condenser and the evaporation pan. The refrigerator appliance also includes a humidity sensor. A controller is in operative communication with the air handler and the humidity sensor. The controller is configured for receiving a humidity measurement for air at the cabinet from the humidity sensor and activating the air handler if the humidity measurement for air at the cabinet is less than a reference value.

In a second exemplary embodiment, a refrigerator appliance is provided. The refrigerator appliance includes a cabinet that defines a chilled chamber. A sealed system is charged with a refrigerant and is configured for generating chilled air within the chilled chamber of the cabinet. The refrigerator appliance also includes means for measuring humidity of an atmosphere about the cabinet and means for increasing humidity of the atmosphere about the cabinet.

In a third exemplary embodiment, a method for operating a refrigerator appliance is provided. The method includes directing refrigerant through a condenser of the refrigerator appliance, measuring a relative humidity of air about the refrigerator appliance, and operating an air handler of the refrigerator appliance in order to direct a flow of air across the condenser and an evaporation pan of the refrigerator appliance if the relative humidity of air about the refrigerator appliance is less than a reference value at the step of measuring. Liquid water within the evaporation pan evaporates during the step of operating.

DETAILED DESCRIPTION

FIG. 1depicts a refrigerator appliance10according to an exemplary embodiment of the present subject matter. It should be appreciated that the term “refrigerator appliance” is used in a generic sense herein to encompass any manner of refrigeration appliance, such as a freezer, refrigerator/freezer combination, and any style or model of conventional refrigerator. In the illustrated exemplary embodiment, refrigerator appliance10is depicted as an upright refrigerator having a cabinet or casing12that defines chilled compartments for storage of food items therein. In particular, the refrigerator appliance10includes upper fresh-food compartments14having doors16and lower freezer compartment18having upper drawer20and lower drawer22. The drawers20,22are “pull-out” drawers in that they can be manually moved into and out of the freezer compartment18on suitable slide mechanisms.

FIG. 2is a schematic view of certain components of refrigerator appliance10including a sealed refrigeration system60. A machinery compartment62(e.g., positioned at a bottom portion of casing12) contains components for executing a known vapor compression cycle for cooling air. The components include a compressor64, a condenser66, an expansion valve68, and an evaporator70connected in series and charged with a refrigerant. As will be understood by those skilled in the art, sealed system60may include additional components, e.g., at least one additional evaporator, compressor, expansion valve, and/or condenser. As an example, sealed system60may include two evaporators.

Within sealed system60, gaseous refrigerant flows into compressor64, which operates to increase the pressure of the refrigerant. This compression of the refrigerant raises its temperature, which is lowered by passing the gaseous refrigerant through condenser66. Within condenser66, heat exchange with ambient air takes place so as to cool the refrigerant and cause the refrigerant to condense to a liquid state. An air handler or fan72is used to pull air across condenser66, as illustrated by arrows AC, so as to provide forced convection for a more rapid and efficient heat exchange between the refrigerant within condenser66and the ambient air. Thus, as will be understood by those skilled in the art, increasing air flow across condenser66can, e.g., increase the efficiency of condenser66by improving cooling of the refrigerant contained therein.

An expansion device (e.g., a valve, capillary tube, or other restriction device)68receives liquid refrigerant from condenser66. From expansion device68, the liquid refrigerant enters evaporator70. Upon exiting expansion device68and entering evaporator70, the liquid refrigerant drops in pressure and, e.g., at least partially, vaporizes. Due to the pressure drop and phase change of the refrigerant, evaporator70is cool relative to compartments14,18of refrigerator appliance10(FIG. 1). As such, cooled air is produced and configured to refrigerate compartments14,18of refrigerator appliance10(FIG. 1). Thus, evaporator70is a type of heat exchanger which transfers heat from air passing over evaporator70to refrigerant flowing through evaporator70.

Collectively, the vapor compression cycle components in a refrigeration circuit, associated fans, and associated compartments are sometimes referred to as a sealed refrigeration system operable to force cold air through refrigeration compartments14,18(FIG. 1). The sealed system60depicted inFIG. 2is provided by way of example only. Thus, it is within the scope of the present subject matter for other configurations of the sealed system to be used as well.

Refrigerator appliance10is further equipped with a controller50to regulate operation of refrigerator appliance10. Thus, controller50is in operative communication with various components of refrigerator appliance10including compressor64. Controller50may selectively activate and deactivate compressor64in order to operate sealed system60in the manner described above.

Controller50may include a memory and microprocessor, such as a general or special purpose microprocessor operable to execute programming instructions or micro-control code associated with a cleaning cycle. The memory may represent random access memory such as DRAM, or read only memory such as ROM or FLASH. In one embodiment, the processor executes programming instructions stored in memory. The memory may be a separate component from the processor or may be included onboard within the processor. Alternatively, controller50may be constructed without using a microprocessor, e.g., using a combination of discrete analog and/or digital logic circuitry (such as switches, amplifiers, integrators, comparators, flip-flops, AND gates, and the like) to perform control functionality instead of relying upon software.

Controller50may be positioned in a variety of locations throughout refrigerator appliance10. Input/output (“I/O”) signals may be routed between the controller50and various operational components of refrigerator appliance10along wiring harnesses that may be routed through casing12. The controller50may include a user interface panel (not shown) through which a user may select various operational features and modes and monitor progress of the refrigerator appliance10. The user interface panel of controller50may represent a general purpose I/O (“GPIO”) device or functional block. In one embodiment, the user interface panel of controller50may include input components, such as one or more of a variety of electrical, mechanical or electro-mechanical input devices including rotary dials, push buttons, and touch pads. The user interface panel of controller50may also include a display component, such as a digital or analog display device designed to provide operational feedback to a user.

It should be understood that during operation of sealed system60water vapor, e.g., from air within refrigeration compartments14,18(FIG. 1) can freeze upon contact with evaporator70. For example, refrigerant within evaporator70may reach a temperature below the freezing point of water. Thus, water vapor contacting evaporator70may freeze and create a frost buildup (not shown) on evaporator70. Such frost buildup may continue to grow during operation of sealed system60. For example, when a user opens freezer doors20,22and permits fresh water vapor containing air to enter freezer chamber18.

To avoid potential negative effects of such frost build up on sealed system60operation, sealed system60is configured for executing a defrost cycle. For example, sealed system60may deactivate compressor64for a period of time sufficient for the frost buildup on evaporator70to melt. As another example, a heating element may be activated to melt the frost buildup. However, when the frost buildup melts, a volume of liquid runoff (e.g, water) is produced that can freeze upon reactivation of compressor64and negatively affect sealed system60and, in particular, evaporator70. Thus, such liquid runoff is directed away from evaporator70via a drain line or conduit90(FIG. 3). In the exemplary embodiment shown inFIG. 2, the liquid runoff is directed to an evaporation pan80(FIG. 3).

Refrigerator appliance10also includes an ice maker92and an ice bucket94. Ice maker92is configured for generating or forming ice cubes. Ice cubes from ice maker92are directed to and stored within an ice bucket94. Sealed system60can maintain air around ice bucket94below the freezing temperature of water in order to limit or prevent melting of ice cubes within ice bucket94. However, sealed system60can stop functioning for a variety of reasons, such as disruption of an electrical power supply to sealed system60, mechanical failure, etc. If ice cubes within ice bucket94are not maintained below the freezing temperature of water, ice cubes within ice bucket94melt and generate liquid runoff. Such liquid runoff can fill ice bucket94and negatively affect operation of refrigeration appliance10. Thus, such liquid runoff is directed out of ice bucket94via drain conduit90(FIG. 3). In the exemplary embodiment shown inFIG. 2, the liquid runoff is directed to evaporation pan80(FIG. 3).

Refrigerator appliance10also includes features for increasing humidity of an atmosphere about refrigerator appliance10. In particular, refrigerator appliance10includes a humidifier100positioned within machinery compartment62at the bottom portion of casing12. Humidifier100is operatively coupled to controller50such that controller50may selectively activate and deactivate humidifier100, as discussed in greater detail below. Humidifier100may be any suitable type of humidifier. For example, humidifier100may be a cool mist humidifier, a warm mist humidifier, an ultrasonic humidifier or a mechanical humidifier.

FIG. 3provides another schematic view of certain components of refrigerator appliance10including humidifier100. In the exemplary embodiment shown inFIG. 3, humidifier100operates in a similar manner to a warm mist humidifier. As discussed above, humidifier100may be any suitable humidifier for increasing humidity of an atmosphere about refrigerator appliance10in alternative exemplary embodiments. Humidifier100is discussed in greater detail below.

As may be seenFIG. 3, refrigerator appliance10includes evaporation pan80. Evaporation pan80extends between a top portion82and a bottom portion84, e.g., along a vertical direction. Evaporation pan80also defines a containment volume86. Liquid water directed to evaporation pan80flows into containment volume86and is stored within containment volume86. Evaporation pan80is open or uncovered at top portion82of evaporation pan80such that liquid water stored within containment volume86of evaporation pan80is exposed to ambient atmosphere, e.g., and evaporates over time.

Refrigerator appliance10includes various features for facilitating or assisting with evaporating liquid water from containment volume86of evaporation pan80. For example, fan72is positioned adjacent, e.g., directly above, evaporation pan80and is positioned and/or oriented for urging a flow of air across or over liquid water within containment volume86of evaporation pan80during operation of fan72. Thus, fan72may urge a flow of air across both condenser66and evaporation pan80. Evaporation pan80is also positioned, e.g., directly, below condenser66within machinery compartment62of casing12. Refrigerant within condenser66can assist with heating air directed towards liquid water within containment volume86of evaporation pan80by fan72in order to assist with evaporating liquid water from containment volume86of evaporation pan80. In addition, coils of condenser66may extend into containment volume86of evaporation pan80in order to facilitate heat transfer between refrigerant within condenser66and the liquid water within containment volume86of evaporation pan80.

Humidifier100also includes a wick110. Wick110is positioned within containment volume86of evaporation pan80and extends from containment volume86of evaporation pan80towards the flow of air from fan72. Wick110is configured for drawing or wicking liquid water from containment volume86of evaporation pan80towards the flow of air from fan72. Thus, liquid water within wick110may be distributed or disposed within the flow of air from fan72in order to assist with evaporating such water. Wick110may include any suitable hydroscopic or absorptive material that is suitable for moving liquid water from containment volume86of evaporation pan80towards flows of air from fan72, e.g., via capillary action. For example, wick110may include a sponge or a fibrous material.

Humidifier100also includes a humidity sensor120and a temperature sensor122. Humidity sensor120and temperature sensor122are in operative communication with controller50such that measurement or signals from humidity sensor120and temperature sensor122may be received and/or recorded by controller50. Humidity sensor120is configured for measuring a, e.g., relative, humidity of air about refrigerator appliance10. Humidity sensor120may be any suitable type of humidity sensor. For example, humidity sensor120may be a resistive humidity sensor, a capacitive humidity sensor, a thermal conductivity humidity sensor or a psychrometer. Temperature sensor122is configured for measuring a temperature of air about refrigerator appliance10. Temperature sensor122may be any suitable type of temperature sensor. For example, temperature sensor122may be a thermocouple or a thermistor. Temperature measurements from temperature sensor122may assist humidity sensor120and/or controller50with more accurately and/or precisely measuring the humidity of air about refrigerator appliance10, as will be understood by those skilled in the art.

As discussed above, controller50is in operative communication with fan72and humidity sensor120. In particular, controller50is programmed or configured for receiving a humidity measurement for air at or around casing12of refrigerator appliance10from humidity sensor120. Controller50is also programmed or configured for activating fan72and blowing or urging air across containment volume86of evaporation pan80if the humidity measurement for air at or around casing12of refrigerator appliance10is less than a reference value, e.g., thirty percent relative humidity. When fan72is operating, air from fan72evaporates liquid water within containment volume86of evaporation pan80and thereby increases the humidity of air about or around casing12of refrigerator appliance10. Thus, controller50may activate humidifier100in order to increase the humidity of air at or around casing12if controller50detects that the humidity of air at or around casing12is low. In addition, operation of humidifier100also assists with cooling refrigerant within condenser66, as discussed above. Thus, humidifier100may operate efficiently relative to separate humidifiers and refrigerator appliances.

Humidifier100also includes a water conduit130and a valve132, such as solenoid valve. Water conduit130is configured to be coupled or connected to a water supply (not shown), such as a municipal water supply or a well. An outlet134of water conduit130is positioned at or adjacent containment volume86of evaporation pan80. Thus, water conduit130may extend from the water supply to containment volume86of evaporation pan80.

Valve132is coupled or mounted to water conduit130. When valve132is open, liquid water from the water supply flows through water conduit130into containment volume86of evaporation pan80. Conversely, valve132blocks or prevents liquid water from flowing from water conduit130into containment volume86of evaporation pan80when valve132is closed. Controller50is operatively coupled to valve132and is configured for selectively opening and closing valve132in order to regulate the flow of liquid water from water conduit130into containment volume86of evaporation pan80, as discussed in greater detail below.

As may be seen inFIG. 3, humidifier100includes a water level sensor140. Water level sensor140is positioned at or adjacent containment volume86of evaporation pan80. Water level sensor140is configured for measuring or determining a height of liquid water within containment volume86of evaporation pan80. Water level sensor140may be any suitable type of sensor for measuring or determining the height of liquid water within containment volume86of evaporation pan80. For example, water level sensor140may be a float ball sensor, a float switch, a pressure transducer or switch, a conductive water level sensor, an optical sensor, etc. Controller50is in operative communication with water level sensor140. Controller50is programmed or configured for opening valve132in order to direct liquid water into containment volume86of evaporation pan80via water conduit130when water level sensor140signals controller50that the height of water within containment volume86of evaporation pan80is less than a predetermined height. Thus, in certain exemplary embodiments, a user need not manually fill containment volume86of evaporation pan80with water in order to operate humidifier100.

Refrigerator appliance10also includes drain conduit90. As discussed above, drain conduit90extends between evaporator70of sealed system60(FIG. 2) and containment volume86of evaporation pan80. Thus, liquid runoff from evaporator70and/or ice bucket94may be directed to containment volume86of evaporation pan80during defrosting of evaporator70. Such liquid runoff may assist with limiting or reducing a volume of fresh water from water conduit130required for operating humidifier100. In addition, in certain exemplary embodiments, humidifier100need not include water conduit130and valve132and may rely upon liquid runoff from evaporator70and manual refilling of evaporation pan80to supply liquid water for humidifier100.

FIG. 4illustrates a method400for operating a refrigerator appliance according to an exemplary embodiment of the present subject matter. Method400may be used to operate any suitable refrigerator appliance. For example, method400may be used to operate refrigerator appliance10. Controller50of refrigerator appliance10may be programmed or configured to implement method400.

At step410, controller50operates or works sealed system60in order to cool fresh food and freezer chambers14,18. For example, controller50may activate compressor64such that, e.g., hot, refrigerant flows through condenser66at step410. At step420, a relative humidity of air about refrigerator appliance10is measured or determined. For example, controller50may receive a signal from humidity sensor120corresponding to the relative humidity of air about refrigerator appliance10at step420. At430, controller50determines whether the relative humidity of air about refrigerator appliance10measured at step420is less than a predetermined value, e.g., fifty percent relative humidity, forty percent relative humidity or thirty percent relative humidity. At step450, controller50activates or operates fan72is if the measured relative humidity of air about refrigerator appliance10is less than the reference value at step440.

When fan72is operated at step450, fan72directs a flow of air across the condenser66and evaporation pan80. The flow of air from fan72evaporates water within containment volume86of evaporation pan80and thereby increases the relative humidity of air about refrigerator appliance10. Refrigerant within condenser66may heat the flow of air prior to the flow of air crossing evaporation pan80in order to increase or assist evaporation of liquid water within containment volume86of evaporation pan80with the flow of air from fan72. Thus, controller50may activate fan72to increase the relative humidity of air about refrigerator appliance10at step450if the air about refrigerator is dry. In such a manner, method400utilizes various components of refrigerator appliance10in order to humidify air about refrigerator appliance10.

At step460, the height of liquid water within containment volume86of evaporation pan80is determined or measured. For example, controller50may receive a signal from water level sensor140in order to determine the height of liquid water within containment volume86of evaporation pan80at step460. At step470, controller50opens valve132if the height of liquid water within containment volume86of evaporation pan80is less than a predetermined height. Thus, controller50may open valve132and automatically refill containment volume86of evaporation pan80with liquid water to permit further operation of humidifier100without requiring manual refilling of evaporation pan80.