Patent Application
20190128596
The present invention relates generally to the field of sensing devices, and relates more particularly to a tunneling magnetoresistance (TMR) door sensor for refrigeration appliances.
A typical refrigeration appliance (e.g., refrigerator, freezer, beverage cooler, etc.) includes a pushbutton door switch that is built into the frame of the appliance. The door switch is physically depressed by a door of the appliance when the door is closed. Thus, when the pushbutton switch is released, a control unit within the appliance may determine that the door has been opened and may perform certain operations accordingly. For example, a light within a refrigeration compartment of the appliance may be turned on, a compressor of the appliance may be activated, etc.
A shortcoming associated with conventional pushbutton door switches is that they include moving, mechanical components that may become worn and/or damaged over the course of use, which may necessitate repair or replacement of a door switch. Furthermore, conventional pushbutton door switches protrude from the frames of refrigeration appliances and thus detract from the overall aesthetic appearance of an appliance.
It is with respect to these and other considerations that the present improvements may be useful.
This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended as an aid in determining the scope of the claimed subject matter.
An exemplary embodiment of a refrigeration appliance in accordance with the present disclosure may include a frame defining a refrigeration compartment, a door connected to the frame and having a door gasket with a magnet disposed therein, the door movable between an open position in which the refrigeration compartment is accessible and a closed position in which the door covers the refrigeration compartment, and a tunneling magnetoresistance (TMR) door sensor disposed within the frame, wherein the magnet is positioned adjacent the TMR door sensor when the door is in the closed position.
Another exemplary embodiment of a refrigeration appliance in accordance with the present disclosure may include a frame defining a refrigeration compartment, a refrigerator door connected to the frame and having a door gasket with a magnet disposed therein, the refrigerator door movable between an open position in which the refrigeration compartment is accessible and a closed position in which the refrigerator door covers the refrigeration compartment and the door gasket forms a seal between the refrigerator door and the frame, the magnet holding the door gasket to the frame in the closed position, a tunneling magnetoresistance (TMR) door sensor disposed within the frame, wherein the magnet is positioned adjacent the TMR door sensor when the door is in the closed position, and a control unit connected to the TMR door sensor and to a light within the refrigeration compartment, wherein the control unit is adapted to detect a decrease in a resistivity of the TMR door sensor and resultantly activate the light when the door is opened from the closed position.
An exemplary embodiment of a refrigeration appliance having a tunneling magnetoresistance door sensor in accordance with the present disclosure will now be described more fully hereinafter with reference to the accompanying drawing. The refrigeration appliance of the present disclosure may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will convey certain exemplary aspects of the refrigeration appliance to those skilled in the art.
Referring to
The refrigerator door 12 and the freezer door 14 may include respective door gaskets 22, 24 attached to interior surfaces thereof. The door gaskets 22, 24 may have respective magnets 26, 28 disposed within them. The magnets 26, 28 may be flexible strip or tape magnetics that may extend through substantially the entire interiors of the door gaskets 22, 24, entirely surrounding the open fronts of the refrigeration compartment 16 and the freezer compartment 18, respectively. In various alternative embodiments, the magnets 26, 28 may extend around less than the entireties of the open fronts of the refrigeration compartment 16 and the freezer compartment 18.
When the refrigerator door 12 and the freezer door 14 are closed, the magnets 26, 28 may be attracted to the metallic frame 30 of the refrigerator 10, causing the door gaskets 22, 24 to be compressed between the frame 30 and each of the refrigerator door 12 and the freezer door 14. The door gaskets 22, 24 may thus seal the refrigeration compartment 16 and the freezer compartment 18 against the ingress of heat. The door gaskets 22, 24 and the magnets 26, 28 are conventional refrigerator components that will be familiar to those of ordinary skill in the art and will therefore not be described in any greater detail herein.
The refrigerator 10 may further include first and second tunneling magnetoresistance (TMR) door sensors 32, 34 disposed entirely within the frame 30. Specifically, the first TMR door sensor 32 may be positioned within the frame 30 such that when the refrigerator door 12 is closed, the magnet 26 in the door gasket 22 of the refrigerator door 12 is disposed in close proximity to (e.g., within 2 inches of) the first TMR door sensor 32. Similarly, the second TMR door sensor 34 may be positioned within the frame 30 such that when the freezer door 14 is closed, the magnet 28 in the door gasket 24 of the freezer door 14 is disposed in close proximity to (e.g., within 2 inches of) the second TMR door sensor 34. The first and second TMR door sensors 32, 34 may be operatively connected to a control unit 36 (e.g., a microprocessor, an application specific integrated circuit (ASIC), etc.) of the refrigerator 10 that is configured to control certain operations of the refrigerator 10 as further described below.
Referring to
The first and second TMR door sensors 32, 34, which may be substantially identical, are formed of a magnetic multilayer film material that exhibits a change in resistivity as a function of applied magnetic field induction. Thus, when the refrigerator door 12 and the freezer door 14 are closed, the first and second TMR door sensors 32, 34 may exhibit relative increases in resistivity due to the relatively close proximities of the magnetic fields emanated by the magnets 26, 28. Conversely, when the refrigerator door 12 and the freezer door 14 are open, the first and second TMR door sensors 32, 34 may exhibit relative decreases in resistivity due to the absence (or near absence) of the magnetic fields emanated by the magnets 26, 28 proximate the first and second TMR door sensors 32, 34, respectively. Thus, the control unit 36 may, by monitoring the resistivities of the TMR door sensors 32, 34, determine whether the refrigerator door 12 and the freezer door 14 are open or closed and may perform certain operations accordingly. For example, when the refrigerator door 12 and/or the freezer door 14 are open, the control unit 36 may activate lights 38, 40 within the refrigeration compartment 16 and/or the freezer compartment 18, respectively. The lights 38, 40 may be deactivated when the refrigerator door 12 and the freezer door 14 are closed. Additionally or alternatively, a compressor (not shown) of the refrigerator 10 may be activated and deactivated depending on the positions of the refrigerator door 12 and the freezer door 14. The present disclosure is not limited in this regard, and it is contemplated that various other operations may be performed or effectuated by the control unit 36 when the refrigerator door 12 and/or the freezer door 14 are determined to be open or closed.
It will be appreciated by those of ordinary skill in the art that the TMR door sensors of the present disclosure provide numerous advantages. For example, the TMR door sensors of the present disclosure are solid state components that have no moving parts, and are therefore not susceptible to mechanical wear. The TMR door sensors of the present disclosure therefore have superior reliability relative to conventional pushbutton door switches. Additionally, the TMR door sensors of the present disclosure can be housed entirely within the frame of a refrigerator and are therefore hidden from view, thus preserving the aesthetic appearance of a refrigerator. Still further, the TMR door sensors of the present disclosure cooperate with existing magnets within conventional refrigerator door gaskets, and therefore do not require any additional components to be installed within the doors of refrigerators.
As used herein, an element or step recited in the singular and proceeded with the word “a” or “an” should be understood as not excluding plural elements or steps, unless such exclusion is explicitly recited. Furthermore, references to “one embodiment” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features.
While the present disclosure makes reference to certain embodiments, numerous modifications, alterations and changes to the described embodiments are possible without departing from the sphere and scope of the present disclosure, as defined in the appended claim(s). Accordingly, it is intended that the present disclosure not be limited to the described embodiments, but that it has the full scope defined by the language of the following claims, and equivalents thereof.
This application claims the benefit of U.S. Provisional Patent Application No. 62/578,910, filed Oct. 30, 2017, the entirety of which is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 62578910 | Oct 2017 | US |
