Magnetic sensing system for multiple door appliances
11892525 ยท 2024-02-06
Assignee
Inventors
Cpc classification
G01R33/091
PHYSICS
F25D23/028
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
G01R33/0088
PHYSICS
G01R33/098
PHYSICS
G01R33/093
PHYSICS
G01R33/072
PHYSICS
International classification
Abstract
A magnetic sensing system includes a sensor and three magnets. The sensor is located within an appliance housing, the appliance having three moving components. The first magnet is disposed in a first orientation adjacent the first moving component, with the position of the first magnet changing in concert with movement of the first moving component. The second magnet is disposed in a second orientation adjacent the second moving component, with the position of the second magnet changing in concert with movement of the second moving component. The third magnet is disposed in a third orientation adjacent the third moving component, with the position of the third magnet changing in concert with movement of the third moving component. The sensor detects displacement of the first moving component, the second moving component, or the third moving component.
Claims
1. A magnetic sensing system comprising: a sensor disposed within a housing of an appliance, wherein the appliance includes a first moving component, a second moving component, and a third moving component; a first magnet disposed in a first orientation adjacent the first moving component, a first position of the first magnet to change in concert with movement of the first moving component; a second magnet disposed in a second orientation adjacent the second moving component, a second position of the second magnet to change in concert with movement of the second moving component; and a third magnet disposed in a third orientation adjacent the third moving component, a third position of the third magnet to change in concert with movement of the third moving component; wherein the sensor detects displacement of the first moving component, the second moving component, or the third moving component; wherein the first magnetic field strength is twice the second magnetic field strength, and the second magnetic field strength is twice the third magnetic field strength.
2. The magnetic sensing system of claim 1, wherein the first orientation is along a first axis, the second orientation is along a second axis, and the third orientation is along a third axis.
3. The magnetic sensing system of claim 2, wherein the first axis is orthogonal to the second axis, the second axis is orthogonal to the third axis, and the third axis is orthogonal to the first axis.
4. The magnetic sensing system of claim 2, wherein the first axis is 905 from the second axis, the second axis is 905 from the third axis, and the third axis is 905 from the first axis.
5. The magnetic sensing system of claim 2, wherein the sensor is disposed along a fourth axis, wherein an intersection of the first axis, the second axis, and the third axis is disposed on the fourth axis.
6. The magnetic sensing system of claim 1, wherein the first magnet is a first distance from the sensor, the second magnet is a second distance from the sensor, and the third magnet is a third distance from the sensor.
7. The magnetic sensing system of claim 6, wherein the first distance equals the second distance and the second distance equals the third distance.
8. The magnetic sensing system of claim 6, wherein the first distance, the second distance, and the third distance are selected to achieve binary weighting of the first magnet, the second magnet, and the third magnet.
9. A magnetic sensing system disposed in an appliance, the magnetic sensing system comprising: an analog sensor centrally located within a housing of the appliance, wherein the analog sensor is oriented along a first axis; a first magnet disposed within a first door of the appliance, the first magnet having a first magnetic field strength, wherein the first magnet is oriented along a second axis in a first position; a second magnet disposed within a second door of the appliance, the second magnet having a second magnetic field strength, wherein the second magnet is oriented along a third axis in a second position; and a third magnet disposed within a third door of the appliance, the third magnet having a third magnetic field strength, wherein the third magnet is oriented along a fourth axis in a third position; wherein the analog sensor detects whether any one of the first door, the second door, and the third door is open; wherein the first position, the second position, and the third position are selected so that the first magnet, the second magnet, and the third magnet are binary weighted.
10. The magnetic sensing system of claim 9, wherein the first magnetic field strength is twice the second magnetic field strength and the second magnetic field strength is twice the third magnetic field strength.
11. The magnetic sensing system of claim 9, wherein the second axis is 905 from the third axis and the third axis is 905 from the fourth axis.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION
(11) For the sake of convenience and clarity, terms such as top, bottom, upper, lower, vertical, horizontal, lateral, transverse, radial, inner, outer, left, and right may be used herein to describe the relative placement and orientation of the features and components of the magnetic sensing system, each with respect to the geometry and orientation of other features and components of the magnetic sensing system appearing in the perspective and cross-sectional views provided herein. Said terminology is not intended to be limiting and includes the words specifically mentioned, derivatives therein, and words of similar import.
(12) The embodiments shown and described herein depict a magnetic sensing system as part of a refrigerator. However, the magnetic sensing system may be part of any appliance having movable components that converge to a single location where the movement of each component is to be individually sensed/detected.
(13) Magnetic sensors are devices that issue an electrical signal upon detecting a magnetic field. There are many types of magnetic sensors: some make use of the Hall effect, and some employ magnetoresistance effects, for example. The Hall effect occurs when a magnetic field is applied at right angles to the current flow of an electric field generated in a solid material, with a voltage, known as the Hall voltage, being produced across the solid material. Magnetoresistance is the change in the electrical resistance of a magnetoresistive element when a magnetic field is applied across the element. Hall effect sensors thus produce a voltage in the presence of a magnetic field while magnetoresistive sensors change their resistance.
(14) A Hall sensor consists of a thin piece of rectangular p-type or n-type semiconductor material, such as gallium arsenide (GaAs), indium antimonide (InSb), or indium arsenide (InAs) that passes a continuous current through itself. A magnetoresistive sensor consists of a very thin insulating layer sandwiched between two ferromagnetic layers, where the first ferromagnetic layer has electrons spinning in one direction and the other ferromagnetic layer has electrons spinning in another direction. Magnetoresistive sensors may include tunnel magnetoresistive (TMR), anisotropic magnetoresistive (AMR), giant magnetoresistive (GMR), to name a few. Hall effect sensors and the magnetoresistive sensors may be linear (analog) or digital, bipolar, or unipolar.
(15) Two types of magnetic sensing systems are disclosed herein for detecting movement of movable components of an appliance. A digital magnetic sensing system employs a digital sensor having digital integrated circuits (IC) to detect three similar magnets connected to the components of the appliance. An analog magnetic sensing system employs an analog sensor and the principles of binary weighting to detect magnets connected to the components. Both magnetic sensing systems are illustrated and described below.
(16) Digital Magnetic Sensing System
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(18) In exemplary embodiments, the digital magnetic sensing system 100 is centrally located in the refrigerator 102, as indicated with a dotted circle in
(19) In exemplary embodiments, the magnet 110, the magnet 112, and the magnet 114 are disposed so that they are relatively close to the digital sensor 116. The magnet 110 is near the door 104 and may be within the housing of the door, attached to the door, or adjacent to the door; the magnet 112 is near the door 106 and may be within the housing of the door, attached to the door, or adjacent to the door; and the magnet 114 is near the door 108 and may be within the housing of the door, attached to the door, or adjacent to the door. While remaining stationary relative to the door 104, the first magnet 110 is disposed in a first orientation and its position changes in concert with the movement of the door. While remaining stationary relative to the door 106, the second magnet 112 is in a second orientation and its position changes in concert with the movement of the door. While remaining stationary relative to the door 108, the third magnet 114 is disposed in a third orientation and its position changes in concert with the movement of the door. When the doors are closed, all four elements of the digital magnetic sensing system 100 occupy the dotted circle indicated in
(20) In exemplary embodiments, the three magnets 110, 112, and 114 are oriented on three orthogonal axes relative to one another, with the south pole (S) of each magnet being positioned closer to the digital sensor 116 than the north pole (N) of the magnet. In exemplary embodiments, the three magnets 110, 112, and 114 are oriented on three orthogonal (or nearly orthogonal) axes relative to one another and converging on three sensing axes (one for each digital IC), as illustrated in
(21) Although shown external to the door 108 to indicate its position, in exemplary embodiments, the magnet 114 is located inside the door 108 (and thus denoted with dotted lines). The digital sensor 116 appears to be directly above the magnet 114 in
(22) In exemplary embodiments, as with components of the refrigerator 102 such as wires, connections, and fixing screws, the components of the digital magnetic sensing system 100 may or may not be visible or accessible to a customer. Thus, the magnet 110, the magnet 112, the magnet 114, and the digital sensor 116 may be located within compartments that are disposed within the housing of the refrigerator 102. Further, although magnet 110, magnet 112, magnet 114, and digital sensor 116 are depicted as rectangular elements of a particular size, the illustrations are merely representative of the relative locations of the components of the digital magnetic sensing system 100 and are not meant to be limiting. In exemplary embodiments, the digital sensor 116 will be able to determine which door 104, 106, or 108 is open based on the magnitude of the magnetic fields generated by magnets 110, 112, and 114.
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(24) In exemplary embodiments, the three magnets 110, 112, and 114 are oriented on three orthogonal (or nearly orthogonal) axes relative to one another and converging on three sensing axes (one for each digital IC), indicated as axes 210, 212, and 214. The magnet 112 and the digital IC 204 are oriented on the axis 210; the magnet 110 and digital IC 206 are oriented on the axis 212; and the magnet 114 and digital IC 208 are oriented on the axis 214. The south pole (S) and north pole (N) designations of each magnet are indicated, with the S side of each magnet facing toward the digital sensor 116. Where the magnets 110, 112, and 114 are orthogonal to one another, the axis 210 may be thought of as the x axis, the axis 212 may be thought of as the y axis, and the axis 214 may be thought of as the z axis.
(25) However, in some embodiments, the digital magnetic sensing system 100 works without the magnets 110, 112, and 114 being strictly orthogonal to one another. Angles a, b, and c indicate the relative angles between axes, with a indicating the angle between the axis 210 and the axis 212, angle b indicating the angle between the axis 210 and the axis 214, and angle c indicating the angle between the axis 212 and the axis 214. In exemplary embodiments, a=b=c=90 such that the three magnets 110, 112, and 114 are orthogonal to one another. In some embodiments, the digital magnetic sensing system 100 also works when abc. In other words, the digital magnetic sensing system 100 can detect movement of magnets 110, 112, and 114 when a=93, b=87, and c=90, as one example. In exemplary embodiments, the digital magnetic sensing system 100 is able to detect movement of magnets 110, 112, and 114 when a=9019, b=9019, and c=9019, preferably when a=905, b=905, and c=905, and more preferably when a=903b=903, and c=903. In exemplary embodiments, when a=905, b=905, and c=905, the magnets are said to be nearly orthogonal to one another.
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(27) In exemplary embodiments, the digital sensor 116 is positioned in the chassis 302 of the refrigerator 102. In alternative embodiments, the digital sensor 116 may be placed between planes of glass or in a liner of one of the compartments of the refrigerator 102.
(28) In
(29) The magnet 110 is shown in
(30) The positions of the magnets 110, 112, 114, and the digital sensor 116 in the illustrations herein are not meant to be limiting.
(31) In addition to the magnets 110, 112, and 114 being disposed on distinct axes, the magnets are also characterized as having a direction, given by a vector. Each magnet includes a north pole and a south pole, with N and S shown for each magnet in
(32) In exemplary embodiments, the digital sensor 116 disposed between the three magnets 110, 112, and 114 is designed to detect magnetic field lines. More particularly, the digital IC 204 detects the magnetic field lines of magnet 112; the digital IC 206 detects the magnetic field lines of magnet 110; and the digital IC 208 detects the magnetic field lines of magnet 114.
(33) In exemplary embodiments, by detecting the magnetic field lines for a given magnet (110, 112, or 114), the digital sensor 116 can determine the position of the magnet individually. Magnetic sensor technology, for example, enables detection of the positions of multiple magnets of which magnetization directions are oriented perpendicular to each other, as are the magnets 110, 112, and 114, in one embodiment. The orientation of the magnets 110, 112, and 114 thus enables a magnetic sensor to detect three discrete digital components on different axes.
(34) In exemplary embodiments, the magnetic field strength, H, of each magnet is considered by the digital magnetic sensing system 100. The magnetic field strength for magnet 110 is given by H.sub.1; the magnetic field strength for magnet 112 is given by H.sub.2; and the magnetic field strength for magnet 114 is given by H.sub.3. In some embodiments, the magnetic field strength for the three magnets is identical: H.sub.1=H.sub.2=H.sub.3.
(35) In exemplary embodiments, the digital sensor 116 of the digital magnetic sensing system 100 is a Hall sensor. The magnetization directions of the three magnets 110, 112, and 114 are coupled uniquely to respective digital ICs 206, 204, and 208 of the Hall sensor such that each sensing component of the Hall sensor detects the open and closed status of each door. Table 1 shows that there are eight possible combinations of the door positions for the three-door refrigerator 102 of
(36) TABLE-US-00001 TABLE 1 Possible door positions for three-door refrigerator with digital magnetic sensing system 100 door 104 door 106 door 108 scenario (magnet 110) (magnet 112) (magnet 114) 1 C C C 2 C O C 3 O C C 4 C C O 5 O O C 6 C O O 7 O C O 8 O O O
(37) It is also possible for the magnetic field strength, H, of all the specifically oriented magnets to be coupled together. In exemplary embodiments, using the individual digital ICs 206, 204, and 208, the digital sensor 116 can individually detect respective magnetic fields to differentiate between the open and closed status of each door of the refrigerator 102. In exemplary embodiments, this is achieved by defining specific zones and determining the door status based on the presence of magnets in the zone. Table 2 features a combination of three magnets for eight zones. The status of each door as opened (O) or closed (C) is determined by the presence of one or more magnets in the zone. Magnet 110 is indicated as M.sub.1, magnet 112 is indicated as M.sub.2, and magnet 114 is indicated as M.sub.3, where M indicates not just the magnetic field strength, given by H, but also the magnetization vector of each magnet.
(38) TABLE-US-00002 TABLE 2 Zones defined for door positions of three-door refrigerator with digital magnetic sensing system 100 door 104 door 106 door 108 zone magnet (M.sub.1) (M.sub.2) (M.sub.3) 1 M.sub.1; M.sub.2; M.sub.3 C C C 2 M.sub.1; M.sub.3 C O C 3 M.sub.2; M.sub.3 O C C 4 M.sub.1; M.sub.2 C C O 5 M.sub.3 O O C 6 M.sub.1 C O O 7 M.sub.2 O C O 8 no magnet O O O
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(45) In exemplary embodiments, the three magnets 110, 112, and 114 are neodymium N45 magnets, with the three magnets each measuring 40 mm10 mm10 mm. In other embodiments, the three magnets 110, 112, and 114 are a neodymium N35 magnets measuring 20 mm10 mm10 mm. In other embodiments, the magnets 110, 112, and 114 are made of ferrite (a ceramic material made by mixing iron oxide with strontium, barium, manganese, nickel, and/or zinc), a combination of aluminum, nickel, and cobalt (AlNiCo), or samarium cobalt (SmCo).
(46) The dimensions and materials provided herein are not meant to be limiting as the digital magnetic sensing system 100 is operable using a variety of magnet and sensor configurations and materials, such as when used with appliances having different features. For example, the doors 104 and 106 of the refrigerator 102 may not be the same width. Or the door 108 may be disposed at the top of the refrigerator 102 while the doors 104 and 106 are disposed at the bottom. In exemplary embodiments, the digital magnetic sensing system 100 can be adjusted to address different appliance configurations, including the nature and size of the magnets, the positions of the magnets, the location of the digital sensor, the type of digital sensor, and the number of doors.
(47) Analog Magnetic Sensing System
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(49) In exemplary embodiments, the analog magnetic sensing system 600 is centrally located in the refrigerator 602, as indicated with a dotted circle in
(50) In exemplary embodiments, the magnet 610, the magnet 612, and the magnet 614 are disposed so that they are relatively close to the analog sensor 616. The magnet 610 is near the door 604 and may be within the housing of the door, attached to the door, or adjacent to the door; the magnet 612 is near the door 606 and may be within the housing of the door, attached to the door, or adjacent to the door; and the magnet 614 is near the door 608 and may be within the housing of the door, attached to the door, or adjacent to the door. When the doors are closed, all four elements of the analog magnetic sensing system 600 occupy the dotted circle indicated in
(51) In exemplary embodiments, the three magnets 610, 612, and 614 are oriented on three orthogonal axes relative to one another, with the south pole (S) of each magnet being positioned closer to the analog sensor 616 than the north pole (N) of the magnet. In exemplary embodiments, the three magnets 610, 612, and 614 are oriented on three orthogonal (or nearly orthogonal) axes relative to one another, with the analog sensor 616 occupying a fourth sensing axis, as illustrated in
(52) Although shown external to the door 608 to indicate its position, in exemplary embodiments, the magnet 614 is located inside the door 608 (and thus denoted with dotted lines). The analog sensor 616 appears to be directly above the magnet 614 in
(53) In exemplary embodiments, as with components of the refrigerator 602 such as wires, connections, and fixing screws, the components of the analog magnetic sensing system 600 may or may not be visible or accessible to a customer. Thus, the magnet 610, the magnet 612, the magnet 614, and the analog sensor 616 may be located within compartments that are disposed within the housing of the refrigerator 602. Further, although magnet 610, magnet 612, magnet 614, and analog sensor 616 are depicted as rectangular elements of a particular size, the illustrations are merely representative of the relative locations of the components of the analog magnetic sensing system 600 and are not meant to be limiting. In exemplary embodiments, the analog sensor 616 will be able to determine which door 604, 606, or 608 is open based on the magnitude of the magnetic fields generated by magnets 610, 612, and 614.
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(56) However, in some embodiments, the analog magnetic sensing system 600 works without the magnets 610, 612, and 614 being strictly orthogonal to one another. Angles d, e, and f indicate the relative angles between axes, with d indicating the angle between axis 704 and the axis 706, angle e indicating the angle between the axis 704 and axis 708, and angle f, indicating the angle between the axis 706 and axis 708. In exemplary embodiments, d=e=f=90 such that the three magnets 610, 612, and 614 are orthogonal to one another. In some embodiments, the analog magnetic sensing system 600 also works when d e f. In other words, the analog magnetic sensing system 600 can detect movement of magnets 610, 612, and 614 when d=90, e=87, and f=93, as one example. In exemplary embodiments, the analog magnetic sensing system 600 is able to detect movement of magnets 610, 612, and 614 when d=9017, e=9017, and f=9017, preferably when d=905, e=905, and f=905, and more preferably when d=903, e=903, and f=903. In exemplary embodiments, when d=905, e=905, and f=905, the magnets are said to be nearly orthogonal to one another.
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(58) In exemplary embodiments, the analog sensing axis 702 intersects the axes 704, 706, and 708. Thus, the analog sensor 616 may be positioned at the intersection point between the axes 704, 706, and 708. However, the analog sensor 616 may be positioned anywhere along the analog sensing axis 702. Angles g, h, and i are also shown. Angle g is the angle between the axis 704 and the analog sensing axis 702; angle h is the angle between the axis 706 and the analog sensing axis; and angle i is the angle between the axis 708 and the analog sensing axis.
(59) In exemplary embodiments, the analog sensing axis 702 may be along the axis 704 (where g=0) or may be g from the axis 704, where g is non-zero. Similarly, the analog sensing axis 702 may be along the axis 706 (where h=0) or may be h from the axis 706, where h is non-zero. And the analog sensing axis 702 may be along the axis 708 (where i=0) or may be i from the axis 708, where i is non-zero.
(60) In exemplary embodiments, the analog magnetic sensing system 600 employs the principle of binary weighting. The binary weighting may be based on the angle between the analog sensor 616 and each of the three magnets or, in other words, the angles between the axis 704, 706, and 708 of magnets 612, 610, and 614 and the analog sensing axis 702, which are given by g, h, and i, respectively. In some embodiments, the angles g, h, and i are selected so that there is a binary weighted coupling factor between the magnets and the analog sensor 616. Thus, as one example, angle g may be selected so that magnet 612 has a coupling factor of 1, angle h may be selected so that magnet 610 has a coupling factor of 2, and angle i may be selected so that magnet 614 has a coupling factor of 4.
(61) Alternatively, in exemplary embodiments, the three magnets 610, 612, and 614 of the analog magnetic sensing system 600 are selected to be binary weighted.
(62) In
(63) In further embodiments, the analog magnetic sensing system 600 may adjust the distances of the magnets relative to the analog sensor 616 based on the magnetic field strength, H. Thus, in some embodiments, a magnet having a higher magnetic field strength is positioned farther from the analog sensor 616 than a magnet having a lower magnetic field strength. This principle is illustrated in
(64) Further, the analog magnetic sensing system 600 may adjust the distances but keep the magnetic field strengths of the magnets the same, as illustrated in
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(66) In exemplary embodiments, the analog magnetic sensing system 600 may adjust the polarity of one or more magnets relative to the analog sensor 616. As one example, the magnet 610 may have its south pole disposed closer to the analog sensor 616 while the magnet 612 and the magnet 614 have their north poles disposed closer to the sensor. Other configurations are possible. The analog magnetic sensor system 600 is flexible in how the polarity of the magnets are positioned relative to the sensor.
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(68) In exemplary embodiments, the analog sensor 616 is positioned in the chassis 802 of the refrigerator 602. In alternative embodiments, the analog sensor 616 may be placed between planes of glass or in a liner of one of the compartments of the refrigerator 602.
(69) In
(70) The positions of the magnets 610, 612, 614, and the analog sensor 616 in the illustrations herein are not meant to be limiting.
(71) Table 3 shows that there are eight possible combinations of the door positions for the three-door refrigerator 602 of
(72) TABLE-US-00003 TABLE 3 Possible door positions for three-door refrigerator with analog magnetic sensing system 600 door 604 door 606 door 608 scenario (magnet 610) (magnet 612) (magnet 614) 1 C C C 2 C O C 3 O C C 4 C C O 5 O O C 6 C O O 7 O C O 8 O O O
(73) It is also possible for the magnetic field strength, H, of all the specifically oriented magnets to be coupled together. In exemplary embodiments, the analog sensor 616 can detect the resultant vector field to differentiate between the open and closed status of each door of the refrigerator 602. In exemplary embodiments, this is achieved by defining specific zones and determining the door status based on the presence of magnets in the zone. Table 4 features a combination of three magnets for eight zones. The status of each door as opened (O) or closed (C) is determined by the presence of one or more magnets in the zone. Magnet 610 is indicated as M.sub.1, magnet 612 is indicated as M.sub.2, and magnet 614 is indicated as M.sub.3, where M indicates not just the magnetic field strength, given by H, but also the magnetization vector of each magnet.
(74) TABLE-US-00004 TABLE 4 Zones defined for door positions of three-door refrigerator with analog magnetic sensing system 600 door 604 door 606 door 608 zone magnet (M.sub.1) (M.sub.2) (M.sub.3) 1 M.sub.1 + M.sub.2 + M.sub.3 C C C 2 M.sub.1 + M.sub.3 C O C 3 M.sub.2 + M.sub.3 O C C 4 M.sub.1 + M.sub.2 C C O 5 M.sub.3 O O C 6 M.sub.1 C O O 7 M.sub.2 O C O 8 no magnet O O O
(75) Similarly, the zones defined in Table 4 can be used by the analog magnetic sensing system 600. The status of each door as opened (O) or closed (C) is determined by the presence of one or more magnets in the zone. M.sub.1, M.sub.2, and M.sub.3, indicate not just the magnetic field strength, given by H, but also the magnetization vector of each magnet. As indicated in Table 4, it is the sum of the magnetic fields that is interpreted by the analog sensor 616, rather than the individual magnetic fields interpreted by the digital sensor 116 (using its individual digital ICs).
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(77) As in Table 4, magnet 610 is shown as M.sub.1, magnet 612 is given as M.sub.2, and magnet 614 is given as M.sub.3. Further, circles of varying size are used to indicate the relative magnetic field strength and direction of each magnet. In this example, the magnets are binary weighted so that the magnetic field strength, H.sub.2, of magnet M.sub.2 is twice the magnetic field strength, H.sub.3, of magnet M.sub.3 and the magnetic field strength, H.sub.1, of magnet M.sub.1 is twice the magnetic field strength of magnet M.sub.2 (and thus four times the magnetic field strength of magnet M.sub.3). Stated mathematically, H.sub.1=2H.sub.2=4H.sub.3. In exemplary embodiments, the analog sensor 616 is located along the analog sensing axis 702, and the magnets, M.sub.1, M.sub.2, and M.sub.3 are orthogonal or nearly orthogonal to one another.
(78) Because the magnetic field strength and direction of the three magnets 610, 612, and 614 are specially oriented relative to each other to create a resultant vector field, the analog sensor 616 can differentiate between doors of the refrigerator. Densely dotted bubble denoted M.sub.1 s the magnetic field strength of magnet 610; dotted bubble denoted M.sub.2 is the magnetic field strength of magnet 612; and sparsely dotted bubble denoted M.sub.3 is the magnetic field strength of magnet 614. The analog sensor 616 is shown as a square and is centrally located. In contrast to the digital sensor 116 of the digital magnetic sensing system 100, the analog sensor 616 of the analog magnetic sensing system 600 can determine the opened and closed status of the doors based on a binary weighted response.
(79) In
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(84) In exemplary embodiments, the analog sensor 616 outputs a continuous voltage in response to measuring the vector field of all three magnets. From the output voltage, eight voltage ranges are defined to identify which of the doors of the refrigerator are closed. Thus, in zone 1 (
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(86) 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.
(87) While the present disclosure refers 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.