Microwave apparatus, and feature for protective door

Abstract

A microwave oven apparatus may comprise a cabinet, a magnetron, a control panel, a chamber door, a primary door input member, a secondary unlocking input member, and a controller, wherein the chamber door can be movably mounted to the cabinet, so as to selectively restrict access to a cooking chamber when at a closed position; the primary door input member may be used for releasing the chamber door from the closed position; the secondary unlocking input member may selectively guide the chamber door to an unlocked state; and the controller may be configured to guide a door monitoring operation, the operation comprising: initiating a locking condition on the basis of a predetermined time period in which the chamber door requires a multi-step opening procedure, determining an empty state of the chamber, and initiating an unlocking condition, and under the unlocking condition, the locked state being stopped, and the chamber door being kept in an unlocked state, allowing for a single-step opening procedure at the primary door input member.

Description

Microwave equipment and protective door features Technical Field

[0001] The present subject matter relates generally to microwave devices and, more particularly, to features and methods for protecting doors therefor. Background Art

[0002] A microwave oven generally includes a housing that defines a cooking chamber. The cooking chamber receives food for cooking. A door is pivotally mounted to the housing to provide access to the cooking chamber. Microwave ovens typically heat food by activating an energy source, such as a magnetron, to generate cooking energy or microwaves. To suppress radiant energy waves, microwave ovens typically include a latch mechanism that locks the door in a closed position during cooking. Furthermore, a closed door indication is typically provided to a controller to ensure safe operation of the microwave oven.

[0003] In addition to these safeguards when the microwave oven is open, the inadvertent opening of the microwave door can also be undesirable. For example, food or items within the microwave oven may be heated after cooking, and accidentally opening the microwave door to remove food or items from the microwave appliance may allow users (e.g., young children) to come into contact with the hot items before they are ready to be served. To address these issues, recently proposed regulations or standards may require a two-step opening procedure or system for opening the chamber doors of various microwave appliances under certain conditions.

[0004] While additional standards and systems may improve safety in some situations, they can also present challenges. In particular, it can be difficult to inform and educate users about these additional standards or systems. Consequently, users may ignore the new procedures for opening the oven door. This can be particularly frustrating or confusing if these standards or systems are applied when the oven is empty or when the user has already taken appropriate precautions. In some cases, this confusion may even lead to users inadvertently damaging the oven door or other components.

[0005] Summary of the Invention

[0006] Aspects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.

[0007] In one exemplary aspect of the present disclosure, a microwave oven device is provided. The microwave oven device may include a housing, a magnetron, a control panel, a chamber door, a primary door input, a secondary unlocking input, and a controller. The housing may define a cooking chamber. The magnetron may be mounted within the housing and communicate with the cooking chamber to direct microwaves into the cooking chamber. The control panel may be mounted to the housing. The chamber door may be movably mounted to the housing to selectively restrict access to the cooking chamber in a closed position. The primary door input may be attached to the housing and operably communicate with the chamber door to release the chamber door from the closed position. The secondary unlocking input may be attached to the housing to selectively direct the chamber door to an unlocked state. The controller may be in operably communication with the control panel. The controller can be configured to direct door monitoring operations including initiating a locked state in which the chamber door is directed to a locked state based on a predetermined time period, during which the chamber door requires a multi-step opening procedure, determining a clear chamber state before expiration of the predetermined time period, determining the clear chamber state including receiving a clear chamber signal, and initiating an unlocked state before expiration of the predetermined time period and in response to determining the clear chamber state, in which the locked state is deactivated and the chamber door remains in the unlocked state to allow a single-step opening procedure at the primary door input.

[0008] In another exemplary aspect of the present disclosure, a method for operating a microwave oven is provided. The method may include initiating a lock condition, wherein the chamber door is directed to a locked state based on a predetermined time period requiring a multi-step opening procedure for the chamber door. The method may also include determining a clear chamber state before expiration of the predetermined time period. Determining the clear chamber state may include receiving a clear chamber signal. The method may also include initiating an unlock condition, in response to determining the clear chamber state, before expiration of the predetermined time period, wherein the lock condition ceases and the chamber door remains in the unlocked state, thereby allowing a single-step opening procedure at the primary door input.

[0009] These and other features, aspects and advantages of the present invention will be better understood with reference to the following description and appended claims.The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present invention and, together with the description, serve to explain the principles of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] A full and enabling disclosure of the invention, including the best mode thereof, is set forth in the specification with reference to the accompanying drawings to those skilled in the art.

[0011] FIG. 1 provides a perspective view of a microwave oven according to an exemplary embodiment of the present disclosure.

[0012] 2 provides an elevational view of a microwave oven according to an exemplary embodiment of the present disclosure, with the door in a closed position.

[0013] 3 provides a perspective view of the exemplary microwave oven apparatus of FIG. 2 with the door in an open position.

[0014] 4 provides a cross-sectional elevation view of a door release assembly according to an exemplary embodiment of the present disclosure.

[0015] 5A , 5B, and 5C provide cross-sectional elevational views illustrating movement of a door release assembly between extended and retracted positions according to an exemplary embodiment of the present disclosure.

[0016] FIG. 6 provides a perspective view of a microwave oven according to an exemplary embodiment of the present disclosure.

[0017] FIG7 provides an elevational view of a microwave oven according to an exemplary embodiment of the present disclosure.

[0018] FIG8 provides a flowchart of a method of operating a microwave oven apparatus according to an exemplary embodiment of the present disclosure.

[0019] FIG9 provides a flowchart of a method of operating a microwave oven apparatus according to an exemplary embodiment of the present disclosure.

[0020] Repeat use of reference characters in the present specification and drawings is intended to represent same or analogous features or elements of the invention. DETAILED DESCRIPTION

[0021] Reference will now be made in detail to embodiments of the present invention, one or more examples of which are illustrated in the accompanying drawings. Each example is provided by way of explanation of the present invention rather than limitation thereof. In fact, it will be appreciated by those skilled in the art that various modifications and variations may be made to the present invention without departing from the scope of the present invention. For example, a feature illustrated or described as part of an embodiment may be used together with another embodiment to produce another embodiment. Therefore, the present invention is intended to encompass modifications and variations within the scope of the appended claims and their equivalents.

[0022] Reference will now be made in detail to embodiments of the present invention, one or more examples of which are illustrated in the accompanying drawings. Each example is provided by way of explanation of the invention and not as a limitation thereof. Indeed, it will be apparent to those skilled in the art that various modifications and variations may be made to the present invention without departing from the scope of the invention. For example, features shown or described as part of one embodiment may be used together with another embodiment to produce yet another embodiment. Therefore, the present invention is intended to encompass modifications and variations within the scope of the appended claims and their equivalents. Throughout this document, the word "exemplary" is used to mean "serving as an example, instance, or illustration." Furthermore, reference to "an embodiment" or "an embodiment" does not necessarily refer to the same embodiment, although it may refer to the same embodiment. Any embodiment described herein as "exemplary" or "embodiment" is not necessarily to be construed as superior to other embodiments.

[0023] As used herein, the terms "first," "second," and "third" are used interchangeably to distinguish one component from another and do not imply the position or importance of each component. The terms "comprising" and "comprising" are intended to be included in a manner similar to the term "comprising." Similarly, the term "or" is generally intended to be inclusive (i.e., "A or B" is intended to mean "A or B or both"). In addition, in this specification and claims, range limitations may be combined or interchanged. Unless the context or language indicates otherwise, these ranges are identified and include all subranges contained therein. For example, all ranges disclosed herein include endpoints, which can be combined independently of one another. Unless the context clearly states otherwise, the singular forms "a," "an," and "the" include plural references.

[0024] Approximate language, as used herein throughout the specification and claims, may be used to modify any quantitative expression that is permissibly variable without causing a change in the basic function to which it is related. Therefore, a numerical value modified by one or more terms (such as "generally," "about," "approximately," and "substantially") is not limited to the precise value specified. In at least some cases, approximate terms may correspond to the precision of an instrument used to measure a value, or the precision of a method or machine used to construct or manufacture a component or system. For example, an approximate term may refer to being within 10% (i.e., including values ​​that are within 10% greater or less than a specified value). In this regard, for example, when used in the context of an angle or direction, these terms include angles that are within ten degrees greater or less than the angle or direction (e.g., "substantially vertical" includes angles up to ten degrees in any direction, such as clockwise or counterclockwise relative to a vertical direction V).

[0025] Unless explicitly stated otherwise, references to a single processing element (e.g., a "controller," "processor," "microprocessor," etc.) are understood to include more than one processing element. In other words, a "processing element" is generally understood to mean "one or more processing elements." Furthermore, any step or function recited as being performed by a "processing element" or "the processing element" is generally understood to be capable of being performed by "any of the one or more processing elements," unless specifically stated to the contrary. Thus, a first step or function performed by a "processing element" may be performed by "any of the one or more processing elements," while a second step or function performed by a "processing element" may be performed by "any of the one or more processing elements," and not necessarily by the same processing element of the one or more processing elements that performs the first step or function. Furthermore, it should be understood that a reference to a "processing element" or "the processing element" performing multiple steps or functions does not require that at least one discrete processing element be capable of performing each of the multiple steps or functions.

[0026] Typically, it may be useful to restrict access to the cooking cavity of a microwave oven device only under certain conditions. Additionally or alternatively, a microwave oven or method that prevents confusing or unhelpful application of safety-related features to open a microwave oven device door would be beneficial (e.g., without risk of damaging the door or opening mechanism).

[0027] The present disclosure advantageously provides a microwave appliance that can facilitate requirements for selective multi-step opening of a microwave appliance door (e.g., according to standards such as UL 923, 7th Edition). The appliance can include features for determining whether various hazards have been properly considered or whether they are useful given the current state of the microwave appliance. This can advantageously prevent users from inadvertently damaging the appliance or minimize user frustration.

[0028] Turning now to the drawings, FIG1 provides a front perspective view of a microwave oven apparatus (i.e., microwave device or microwave oven) 100, to which the present disclosure may be applied. FIG2 provides an elevational view of the microwave oven apparatus 100 with the chamber door in a closed position. FIG3 provides a front perspective view of the microwave oven 100 with the door in an open position.

[0029] Microwave oven 100 generally includes an insulated cabinet 102. Cabinet 102 defines a cooking chamber 104 for receiving food for cooking. As will be appreciated by those skilled in the art, microwave oven 100 is provided merely as an example, and the present subject matter may be used with any suitable microwave oven, such as a countertop microwave oven, a stovetop microwave oven, etc. Therefore, the exemplary embodiments described in detail herein are not intended to limit the present subject matter to any particular cooking chamber configuration or arrangement.

[0030] As shown, the microwave oven 100 generally defines a vertical direction V, a lateral direction L, and a transverse direction T, each of which is perpendicular to one another so as to generally define an orthogonal coordinate system. The cabinet 102 of the microwave oven 100 extends along the vertical direction V between a top 106 and a bottom 108, along the lateral direction L between a first side 110 (left side when viewed from the front) and a second side 112 (right side when viewed from the front), and along the transverse direction T between a front 114 and a rear 116.

[0031] The microwave oven 100 includes a chamber door 120 that is pivotally or rotatably attached to the cabinet 102 to allow selective access to the cooking chamber 104. As will be described in greater detail below, a separate primary door input 122 and a secondary unlock input 138 are typically provided for releasing and opening the chamber door 120. The separate primary door input 122 and the secondary unlock input 138 can be engaged, for example, in a prescribed sequence of a multi-step opening sequence, wherein the secondary unlock input 138 is engaged first (e.g., as indicated by hand "1" in a first user engagement gesture 160) and then the primary door input is engaged (e.g., as indicated by hand "2" in a second user engagement gesture 162). The primary door input 122 can include a door release button (e.g., a slidable button 144) that selectively allows access to the cooking chamber 104 (e.g., in response to engagement or depression of the door release button 144). In some embodiments, a handle 156 is mounted to the door 120 to assist a user in opening and closing the door 120 to access the cooking chamber 104. For example, a user can pull the handle 156 mounted to the door 120 to assist in opening or closing the door 120, thereby accessing the cooking chamber 104. In some embodiments, a latch or equivalent mechanism can be used to engage the door 120, maintaining the door 120 in a closed position until the door 120 is actuated or released by the primary door input 122, as discussed in greater detail below. The glass pane 124 can provide a view of the contents of the cooking chamber 104 when the door 120 is closed and can also help insulate the cooking chamber 104.

[0032] In some embodiments, the front portion 114 defines a body cavity 118 . The body cavity 118 can pass through the front portion 114 and into the housing 102 in the transverse direction T. The body cavity 118 can house the body of the button 144 .

[0033] The microwave oven 100 is typically configured to heat an item (e.g., food or beverage, using electromagnetic radiation within the cooking chamber 104) during a heating cycle or a portion of a heating cycle. As is generally understood, the microwave device 100 may include one or more heating elements 119, such as a component that operates (e.g., when activated) to generate electromagnetic radiation. For example, the microwave device 100 may include a magnetron heating element 119 (e.g., a cavity magnetron), a high-voltage transformer, a high-voltage capacitor, and a high-voltage diode. When activated, the transformer can provide energy to the magnetron from a suitable energy source (e.g., an electrical outlet). The magnetron can convert the energy into electromagnetic radiation, particularly microwave radiation. The capacitor typically connects the magnetron and the transformer to a chassis, such as through a high-voltage diode. The microwave radiation generated by the magnetron can be transmitted to the cooking chamber 104 via a waveguide.

[0034] The structure and intended function of a microwave oven are generally understood by those skilled in the art and will not be described in further detail herein. According to alternative embodiments, the microwave oven can include one or more heating elements, such as resistive heating elements, inductive heating elements, other microwave heating elements, halogen heating elements, or suitable combinations thereof, positioned within the cooking cavity 104 for heating the cooking cavity 104 and the food positioned therein.

[0035] As shown, a control panel or user interface panel 130 and a user input device 132 can be located on the exterior of the cabinet 102 (e.g., for selecting one or more heating cycles or variables therefor, as will be understood). The user interface panel 130 can represent a general purpose input / output ("GPIO") device or functional block. In some embodiments, the user interface panel 130 can include or be in operative communication with a user input device 132, such as one or more of a variety of digital, analog, electrical, mechanical, or electromechanical input devices, including a rotary dial, a control knob, a button, and a touchpad. The user input device 132 is typically located near the user interface panel 130. In some embodiments, the user input device 130 can be located on the user interface panel 130. The user interface panel 130 can include a feedback component 134, which can include or be provided as a digital or analog display device designed to provide visual operational feedback to the user (e.g., as will be understood). Separate from or in addition to the display device, the feedback component 134 can include or be provided as a speaker device designed to provide audible or auditory feedback from generated sound waves (e.g., as will be understood). Additionally or alternatively, feedback component 134 may include or be provided as a haptic device designed to provide tactile feedback from vibrations generated that are transmitted to a user in contact with interface panel 130 (eg, as will be understood).

[0036] In conjunction with or separate from the control panel or user interface panel 130, the microwave oven 100 can provide a plurality of multi-step inputs for opening or otherwise releasing the chamber door 120 from a closed position (e.g., under certain or selective locking conditions). In some embodiments, the multi-step inputs include separate primary door inputs 122 and secondary unlocking inputs 138, each of which is attached to the cabinet 102 (e.g., directly or indirectly). Separate engagement of the primary door input 122 and the secondary unlocking input 138 can be used to release the chamber door 120 (e.g., under one or more predetermined conditions), as described in greater detail below. In particular, the secondary unlocking input 138 can be provided (e.g., in operative communication with the door lock 154 or the controller 140) to selectively direct the chamber door 120 to an unlocked state when in a locked condition. A primary door input 122 may be provided (eg, in operative communication with the chamber door 120 ) to release the chamber door 120 from a closed position, such as when the chamber door 120 is first unlocked (eg, temporarily or in an unlocked condition).

[0037] Generally, microwave oven 100 can include a controller 140 (e.g., separate from or in addition to primary door input 122 or secondary unlock input 138) in operable communication with a user input device 132. User interface panel 130 of microwave oven 100 can communicate with controller 140 via, for example, one or more signal lines or a shared communication bus, and signals generated in controller 140 operate microwave oven 100 in response to user input via user input device 132. Input / output ("I / O") signals can be routed between controller 140 and various operating components of microwave oven 100. Operation of microwave oven 100 can be regulated by controller 140 operatively coupled to user interface panel 130.

[0038] The controller 140 is a "processing device" or "controller" and may be implemented as described herein. The controller 140 may include memory and one or more microprocessors, microcontrollers, application-specific integrated circuits (ASICs), CPUs, and the like, such as general-purpose or special-purpose microprocessors operable to execute programmed instructions or microcontroller code associated with the operation of the microwave oven 100 (e.g., methods 800 or 900), and the controller 140 is not necessarily limited to a single component. The memory may represent random access memory, such as DRAM, or read-only memory, such as ROM, electrically erasable programmable read-only memory (EEPROM), or FLASH. In one embodiment, the processor executes programmed instructions stored in the memory. The memory may be a separate component from the processor or may be included onboard the processor. Alternatively, the controller 140 may be implemented without a microprocessor (e.g., using a combination of discrete analog and / or digital logic circuits, such as switches, amplifiers, integrators, comparators, flip-flops, AND gates, etc., to perform control functions rather than relying on software).

[0039] In an optional embodiment, a presence detection sensor (PDS) 196 is mounted within the cooking cavity 104. Specifically, the PDS 196 can be mounted on or within the cabinet 102 so as to communicate with at least a portion of the cooking device 100 within the cooking cavity 104 (e.g., on the rotatable plate or support plate 158 or other food receiving portion of the appliance 100). The PDS 196 can be in operable (e.g., wired or wireless) communication with the controller 140 and configured to detect one or more items (e.g., food) on the support plate 158. For example, the PDS 196 can be configured to detect whether or when food is present on the support plate 158 and transmit one or more detection signals corresponding thereto.

[0040] In some embodiments, the PDS 196 is in mechanical communication with the support tray 158. For example, the PDS 196 can be mounted below the support tray 158 (e.g., on a bottom wall or tray). Thus, movement or force of the support tray 158 (e.g., provided by the food) can be at least partially transmitted to the PDS 196. In some embodiments, the PDS 196 includes a force sensor 196A configured to receive a load thereon (e.g., a force, torque, or pressure load generated by the presence of food on the support tray 158). Any suitable force sensor 196A can be provided for the PDS 196. For example, the force sensor 196A can include or be configured as a weight / mass sensor (e.g., configured to detect a weight or mass value corresponding to the food on the support tray 158), a pressure sensor (e.g., configured to detect a pressure value corresponding to the pressure generated by the presence of food on the support tray 158), or a presence switch (e.g., a reed switch, a magnetic resistance switch, a push button switch, or a pressure switch configured to monitor for deflections exceeding a set threshold that may be caused by the presence of food on the support tray 158). Thus, the detection signal may include or correspond to a force signal received from force sensor 196A.

[0041] In additional or alternative embodiments, the PDS 196 is provided as an optical sensor 196B. As shown, the optical sensor 196B can be spaced apart from the support tray 158. For example, the optical sensor 196B can be mounted in the top wall of the housing (i.e., above the support tray 158). Thus, the optical sensor 196B can sense movement or objects (e.g., food) on the support tray 158. Any suitable optical sensor 196B can be provided for the PDS 196. For example, the optical sensor 196B can include or be provided as a camera (e.g., a video camera or a digital camera) having an electronic image sensor that is configured to capture one or more images of the support tray. As an additional or alternative example, the optical sensor can include or be provided as a broken beam sensor that is configured to direct a light beam (e.g., a laser beam or an infrared beam) at the support tray that can be interrupted by the food and thereby detected at the broken beam sensor, as will be understood. Thus, the detection signal can include or correspond to an optical (e.g., image or broken beam) signal received from the optical sensor 196B.

[0042] While specific force sensor 196A and optical sensor 196B are described above, it should be noted that PDS 196 may include or be provided as a suitable sensor assembly configured to detect food within cooking cavity 104 (eg, directly or indirectly), as understood in accordance with this disclosure.

[0043] Turning further to Figures 2-4, Figure 4 provides a cross-sectional elevational view of an exemplary door release assembly 142 of the microwave oven 100 that facilitates opening the chamber door 120 (e.g., moving the chamber door 120 from a closed position (Figure 2) to an open position or other non-closed position (Figure 3)). It should be noted that the illustrated door release assembly 142 is merely an exemplary embodiment and is not intended to limit the present disclosure to any particular mechanism unless expressly required. Accordingly, in light of this disclosure, one of ordinary skill in the art will appreciate that any suitable embodiment for opening or releasing the chamber door 120 is within the scope of the present subject matter.

[0044] As described above, the primary door input 122 can be operably (e.g., mechanically or electronically) connected to the chamber door 120, such as directly or through one or more intermediate components. In some embodiments, the primary door input 122 is provided as a slidable button 144 (e.g., as shown). Thus, the primary door input 122 can move (e.g., translate or pivot) relative to the housing 102. In some such embodiments, the slidable button 144 can move between an extended position (e.g., as shown in dashed lines in FIG4 ) and a retracted position (e.g., as shown in solid lines in FIG4 ). As shown, the retracted position can position the slidable button 144 in a relatively inward position within the housing 102 compared to the extended position. Additionally or alternatively, the retracted position can be configured to cause the chamber door 120 to move from a closed position, as understood in light of the present disclosure.

[0045] In certain embodiments, the primary door input 122 can be in mechanical communication with the chamber door 120 such that movement of the primary door input 112 is transmitted to the chamber door 120 (e.g., via one or more intermediate release mechanisms or drive train components). In the illustrated embodiment, the primary door input 122 is aligned with a first lever 146. Specifically, a rear portion of the slidable button 144 selectively engages the first lever 146 to drive its rotation (e.g., when the slidable button 144 moves from an extended position to a retracted position). The illustrated first lever 146 is also selectively engaged with a second lever or gear 148, which itself selectively engages one or more movable latches 150 (e.g., mounted on the chamber door 120 to hook against one or more corresponding catches 152 secured to the housing 102) in the closed position of the chamber door 120. Conversely, rotation of the first lever 146 can cause rotation of the second lever 148, which in turn causes movement (e.g., vertical translation) of the movable latch 150. Such movement of the movable latch 150 may be used, for example, to lift the movable latch 150 from the corresponding catch 152 , thereby releasing the chamber door 120 , thereby allowing the chamber door 120 to move (eg, pivot) from the closed position.

[0046] As shown, door sensor 136 can be selectively in communication with door 120 (e.g., directly mechanically, or alternatively, indirectly, such as via second lever 148, as shown). Generally, door sensor 136 can be operable to sense the position of door 120 (e.g., closed or open). For example, door sensor 136 can be configured to detect whether or when door 120 is in a closed position. Generally, door sensor 136 can include or be configured as any suitable sensor, such as a contact sensor, a reed switch, a Hall effect sensor, an optical sensor, etc. For example, as shown (e.g., in FIG. 3 ), door sensor 136 can be positioned near second lever 148 to engage the second lever when the second lever 148 is pushed downward or rotated by an engaged movable latch 150. Alternatively, door sensor 136 can be included in or as part of a latch assembly configured to lock or otherwise maintain door 120 in a closed position, as understood in light of the present disclosure.

[0047] Note that while a slidable button 144 is specifically shown in FIG4 , any other suitable primary door input 122 may be provided. For example, briefly turning to FIG7 , the primary door input 122 may be provided as a pull handle 156. As will be appreciated, such an embodiment may allow the chamber door 120 to be released by a user applying a pulling action to the pull handle 156. For example, as the chamber door 120 moves rearward (e.g., pivots) away from the housing 102, the pulling action may be used to simultaneously pull the movable biased latch, causing it to translate upward on the corresponding static catch.

[0048] Turning now to Figures 5A, 5B, and 5C, various cross-sectional elevation views illustrate movement of the door release assembly 142 between an extended position and a retracted position. As described above, the secondary unlock input 138 can be attached to the housing 102 separately from or in addition to the primary door input 122. In some embodiments, the primary door input 122 is provided as an electronic button (e.g., one of the user inputs 132, as shown and commonly understood). The secondary unlock input 138 can be in electrical communication with, for example, the controller 140 or the door lock 154. Thus, user engagement of the secondary unlock input 138 can prompt a corresponding signal to be sent to the controller 140 or the door lock 154.

[0049] Typically, a secondary unlock input 138 can be provided to direct the chamber door 120 to an unlocked state, in which the chamber door 120 can be released (e.g., for a set, temporary period of time or an indefinite period of time, which may be dependent on a non-time-related action). In particular, the secondary unlock input 138 can be provided to facilitate a multi-step opening process from the chamber door 120. Thus, user engagement of the secondary unlock input 138 can be required to be separate or distinct from user engagement of the primary door input 122. Specifically, in order to open the chamber door 120 under certain conditions (e.g., a locked condition), the user can be forced to follow a set procedure in which the user is required to provide a first user engagement action 160 at the secondary unlock input 138 (e.g., to release the chamber door 120 from a locked state to an unlocked state) and then provide a second user engagement action 162 at the primary door input 122 (e.g., to move the chamber door 120 from a closed position, such as to an open position).

[0050] In some embodiments, a secondary unlock input 138 is provided in operable communication with a dedicated door lock 154 (e.g., directly, or alternatively, indirectly, such as via the controller 140). In the illustrated embodiment, the door lock 154 is movably disposed in interference engagement with the first lever 146. Specifically, the door lock 154 is movable between a locked state ( FIG. 5A ) and an unlocked state ( FIG. 5B and FIG. 5C ) (e.g., guided by the controller 140 and a solenoid motor (not shown, corresponding to the door lock 154)). As shown, in the locked state, the door lock 154 generally prevents full actuation or movement of the first lever 146 or the primary door input 122. In contrast, in the unlocked state, the door lock 154 can be decoupled from the first lever 146 or the drivetrain path connected to the primary door input 122. As described above, engagement of the secondary unlock input 138 in the form of a first user engagement action 160 can place the door release assembly 142 in the unlocked state, for example, by moving the door lock 154 into the unlocked state. Subsequently, engagement with the primary door input 122 in the form of a second user engagement action 162 may actuate (eg, the first lever 146 ) the chamber door 120 from the closed position.

[0051] It should be noted that although an electronic button is shown in FIG. 4 , particularly with respect to the secondary unlock input 138 , any other suitable secondary unlock input 138 may be provided. For example, turning briefly to FIG. 6 , the secondary unlock input 138 may be provided as a mechanical button or input 164 (e.g., separate from the user input 132 or in mechanical communication with the door lock 154 ). As will be appreciated, such an embodiment may allow for unlocking the chamber door 120 (e.g., without involving the controller 140 or direct electrical communication to unlock the chamber 120 ). As an example, pushing the mechanical button 164 may forcibly move the interior lock (e.g., FIG. 5A , FIG. 5B , FIG. 5C ) from a locked state to an unlocked state. It will be appreciated that a dedicated engagement switch or sensor may be provided in operable communication with the secondary unlock input 138 (e.g., to detect engagement thereof).

[0052] 8 and 9 , the present disclosure may further relate to an algorithm or method (eg, method 800 or 900 ) for operating a microwave oven appliance (eg, microwave oven 100 ). In an exemplary embodiment, controller 140 may be operated to perform various steps of the algorithm or method according to the present disclosure.

[0053] The algorithm or method (e.g., 800 or 900) can be performed as part of or as part of a door monitoring operation of the microwave oven 100. In particular, the algorithm or method (e.g., 800 or 900) disclosed herein can advantageously detect safety conditions and selectively limit the requirement for a multi-step opening procedure to open a door (e.g., while still allowing the use of a multi-step opening process and preventing confusing or unhelpful application of safety-related features).

[0054] It should be noted that the order of the steps in the algorithms or methods 800 and 900 is for illustrative purposes. In addition, the algorithms or methods 800 and 900 are not mutually exclusive. In other words, the algorithms or methods in the present disclosure may include one or more of the algorithms or methods 800 and 900. All of these can be adopted or described as being completed in a common operation. Unless otherwise stated, one or more steps in the following algorithms or methods 800 and 900 may be changed, rearranged, performed in a different order, or otherwise modified without departing from the scope of the present disclosure.

[0055] Turning specifically to FIG. 8 , at 810 , method 800 includes initiating a heating cycle. Typically, the heating cycle includes activating a heating element (e.g., a magnetron or any additional electrical heating element, such as a resistive heating element, a radiant heating element, an inductive heating element, etc.). The heating cycle can be based on, for example, one or more user-set parameters or parameters independently determined by a controller (e.g., based on one or more sensor signals). Such heating cycles and heating element activations are generally understandable and can be based on known microwave cooking methods. It should be noted that in some embodiments, 810 occurs or is initiated before one or more other steps of method 800. For example, 810 can occur or be initiated before 820 , 830 , 840 , or 850 .

[0056] At 820, method 800 includes initiating a lockout condition, wherein the chamber door is directed to a locked state (e.g., after or simultaneously with 810). Specifically, the chamber door can be set in a closed position and the door lock can be set in a locked state. In some such embodiments, the lockout condition or heating cycle can be prompted or initiated (e.g., automatically) in response to a user-selected heating cycle (e.g., 810). Optionally, a heating time threshold or power level threshold for the heating cycle can be included, such as a minimum threshold for prompting 820.

[0057] The locked condition can be achieved based on a predetermined time period during which the chamber door requires a multi-step opening procedure. Thus, generally, the predetermined time period can be the time period during which a multi-step opening procedure (e.g., as described above) is required to open the chamber door. The predetermined time period effectively sets the time or moment at which the device can be scheduled to switch from the locked condition to the unlocked condition (e.g., without requiring a separate step, instruction, or user intervention with a secondary unlocking input). The predetermined time period can run or continue after 810 or 830. Alternatively, the predetermined time period can begin counting from 810 (or another suitable step below, such as 830). In other words, a timer or tracking program for the predetermined time period can be initiated when (in response to) the heating cycle is determined to have begun, predicted to have ended, determined to have ended, or otherwise expired. In some embodiments, the predetermined time period is a set or fixed value, such as approximately 30 minutes (e.g., starting at 830 or the predicted end time of the heating cycle). In alternative embodiments, the predetermined time period is a variable value based on the selected heating cycle (e.g., set according to a predetermined lookup table, formula, chart, or graph).

[0058] At 830, method 800 includes determining the expiration of the heating cycle. This determination can be based on predicted criteria or, alternatively, on unpredictable criteria. For example, the predicted criteria can include the expiration of a selected cooking time or other parameters of the heating cycle. As an additional or alternative example, the unpredictable criteria can include a user-based interruption of the heating cycle, such as user interaction with one or more inputs (e.g., a primary door input or a secondary unlock input). As will be appreciated, upon or as part of the determined expiration of the heating cycle, the heating element can be deactivated.

[0059] At 840, method 800 includes determining a clear chamber state. Specifically, 840 can be determined before the clear chamber state expires and based at least in part on a received clear chamber signal. Thus, 840 can include receiving a clear chamber signal.

[0060] In some embodiments, a clear chamber signal is received from a secondary unlock input. Conversely, 840 may include receiving an input signal (e.g., corresponding to engagement) at the secondary unlock input, as described above. Optionally, 840 may also include detecting the door being opened and closed. For example, after 820 or 830, 840 may include detecting a door closing event. Such a detected door closing event may be based on a signal received from a door sensor (e.g., upon engagement of the chamber door or when the chamber door is in a closed position), as described above.

[0061] In additional or alternative embodiments, a clear cavity signal is received from a presence sensor (i.e., a PDS). Conversely, 840 may include receiving a detection signal from a presence sensor mounted within the cooking cavity. Furthermore, the detection signal may correspond to an empty state of the cooking cavity. Specifically, a determination may be made as to whether one or more signals are received from the presence detection sensor indicating that one or more food items have been removed from the support plate. If so, an empty or item missing state may be determined, indicating that the food item has been removed (e.g., removed and no longer present on the support plate).

[0062] In some embodiments, determining the empty state includes detecting a decrease in weight (e.g., based on one or more force signals received from a force sensor). The decrease in weight can be, for example, a decrease in a weight value (e.g., compared to a weight value previously detected at 810, 820, or 830) or a switch signal (e.g., indicating that a switch is open or not depressed beyond a set threshold, as would otherwise occur with the presence of food on the support plate).

[0063] In additional or alternative embodiments, determining the empty state is based on one or more optical signals received from an optical sensor. For example, an image can be captured and analyzed to determine that no food is detected in the captured image. In other words, an algorithm that attempts to identify one or more items on the support panel can be applied to the captured image. The attempt to identify the object can be performed by edge matching, divide-and-conquer search, grayscale matching, receptive field response histogram, or another suitable routine (e.g., performed at the controller based on one or more captured images from the camera), as can be understood. As an additional or alternative example, one or more signals from a broken beam sensor can be received and analyzed to determine that the beam is not broken and therefore no food is on the support plate.

[0064] At 850, method 800 includes initiating an unlock condition. Specifically, 850 can be initiated before the clear chamber state expires (e.g., in response to 840). In the unlock condition, the locking condition ceases and the chamber door remains in the unlocked state. This unlocked state can eliminate the need for a multi-step opening procedure (e.g., which needs to be part of the locking condition), and instead allows a single-step opening procedure, such as at the primary door input. Thus, the user can open the door by engaging only the primary door input without engaging the secondary unlock input. The unlock condition can persist for an indefinite period of time (e.g., independent of a predetermined period of time), such as until a new heating cycle is started. In other words, the predetermined period of time (e.g., the timing or tracking thereof) can be canceled.

[0065] 9 , at 910 , method 900 includes initiating a lockout condition. For example, 910 may include initiating a lockout condition in which the chamber door remains in a locked state. Specifically, the chamber door may be set in a closed position and the door lock may be set in a locked state. In some such embodiments, the lockout condition or heating cycle may be prompted or initiated (e.g., automatically) in response to a user-selected heating cycle (e.g., input at a control panel).

[0066] At 920, method 900 includes activating a heating element (e.g., a magnetron or any additional electrical heating element, such as a resistive heating element, a radiant heating element, an inductive heating element, etc.), such as as part of a heating cycle. Activation of such a heating element is generally understood and can be in accordance with known microwave cooking methods.

[0067] At 930, method 900 includes evaluating the heating cycle. Specifically, it can be determined whether the heating cycle of 920 is complete. If it is complete, method 900 can continue to 940. However, if the heating cycle is not complete, method 900 can proceed directly to 980 (e.g., while continuing the heating cycle or activating the heating element).

[0068] At 940 , method 900 includes deactivating the heating element (eg, such heat is not directly generated by the heating element), as will be appreciated. Method 900 may then continue to 950 .

[0069] At 950, method 900 includes evaluating a predetermined time period. Typically, the predetermined time period can be a time period that requires a multi-step opening procedure (e.g., as described above) to open the chamber door. The predetermined time period can effectively set the time or moment when the lock condition can end. Optionally, the predetermined time period can be counted starting from 940. In other words, a timer or tracking program for the predetermined time period can be started when (e.g., in response to) the end of the heating cycle or the deactivation of the heating element. In some embodiments, the predetermined time period is a set value or fixed value, such as approximately 30 minutes (e.g., starting from 940). In an alternative embodiment, the predetermined time period is a variable value based on the selected heating cycle (e.g., set according to a predetermined lookup table, formula, chart, or graph). If the predetermined time period is completed, method 900 can continue to 960. However, if the heating cycle is not completed, method 900 can continue to 970.

[0070] At 960, method 900 includes initiating an unlock condition. In the unlock condition, the locking condition ceases, and the chamber door remains in the unlocked state. This unlocked state can eliminate the need for a multi-step opening procedure (e.g., as part of the locking condition), allowing for a single-step opening procedure, such as at the primary door input. Thus, a user can open the door by engaging only the primary door input without engaging the secondary unlock input. The unlock condition can persist for an indeterminate period of time, such as until a new heating cycle begins.

[0071] At 970, method 900 includes evaluating a clear presence signal received from a presence sensor (i.e., PDS). Specifically, it can be determined whether one or more signals are received from a presence detection sensor indicating whether one or more food items have been moved from the support tray. Thus, 970 can include determining an empty state or item missing state indicating that food items have been moved (e.g., removed and no longer present on the support tray), or alternatively, determining an occupied state indicating that food items are present (e.g., in the support tray).

[0072] In some embodiments, determining the item missing state includes detecting a decrease in weight (e.g., based on one or more force signals received from a force sensor). The decrease in weight can be, for example, a decrease in a weight value (e.g., compared to a weight value detected before 910) or a switch signal (e.g., indicating that a switch is open or not depressed beyond a set threshold, as would otherwise occur if food were present on the support plate).

[0073] In additional or alternative embodiments, determining the item missing state is based on one or more optical signals received from an optical sensor. For example, an image can be captured and analyzed to determine that no food is detected in the captured image. In other words, an algorithm that attempts to identify one or more items on the support panel can be applied to the captured image. The attempt to identify the object can be performed by edge matching, divide-and-conquer search, grayscale matching, receptive field response histogram, or another suitable routine (e.g., performed at the controller based on one or more captured images from the camera), as can be understood. As an additional or alternative example, one or more signals from a broken beam sensor can be received and analyzed to determine that the beam is not broken and therefore no food is on the support plate.

[0074] In some embodiments, determining the occupancy state includes detecting a maintenance or increase in weight (e.g., based on one or more force signals received from a force sensor). The maintenance or increase in weight can be, for example, a hold or increase in a weight value (e.g., compared to a weight value detected before 910) or a switch signal (e.g., indicating that a switch is engaged or depressed beyond a set threshold, the set threshold corresponding to the presence of food on the support plate).

[0075] In additional or alternative embodiments, determining the occupancy state is based on one or more optical signals received from an optical sensor. For example, an image can be captured and analyzed to determine that one or more food items are detected in the captured image. In other words, an algorithm for identifying one or more items on the support panel can be applied to the captured image. Identifying objects can be performed by edge matching, divide-and-conquer search, grayscale matching, receptive field response histograms, or another suitable routine (e.g., performed at the controller based on one or more captured images from the camera), as can be understood. As an additional or alternative example, one or more signals from a broken beam sensor can be received and analyzed to determine that the beam is broken and, therefore, food is present on the support tray.

[0076] If an item missing state is determined, method 900 may continue to 960. However, if an occupied state is determined, method 900 may continue to 980.

[0077] At 980, method 900 includes evaluating the secondary unlock input. Specifically, it can be determined whether a first user engagement action has occurred at the secondary unlock input (e.g., as described above, based on a signal from the secondary unlock input or its absence). If the secondary unlock input has been engaged, method 900 can continue to 982. However, if the secondary unlock input has not been engaged, method 900 can return to an earlier step, such as 950.

[0078] At 982, method 900 includes temporarily unlocking the chamber door. In other words, the door lock may be moved to an unlocked state, for example, for a set temporary time (e.g., between 10 seconds and 1 minute after initiation of 982). Thus, during the duration of the temporary time, the chamber door may be allowed to open (e.g., in response to user engagement of the primary door input).

[0079] At 984, method 900 includes evaluating the primary door input. Specifically, it can be determined whether a second user engagement action occurs at the primary door input within a set temporary time (e.g., based on a signal from the primary door input or its absence, as described above). If the primary door input has been engaged, method 900 can proceed to 986 to deactivate the heating element and then to 960. However, if the primary door input has not been engaged, method 900 can return to an earlier step, such as 950.

[0080] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. If such other examples include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims, then such examples are intended to be within the scope of the claims.

Claims

1. A microwave oven device, comprising: a housing defining a cooking chamber; a magnetron installed in the housing and communicating with the cooking cavity to guide the microwaves into the cooking cavity; a control panel mounted to the cabinet; a cavity door movably mounted to the cabinet to selectively restrict access to the cooking cavity in a closed position; a primary door input attached to the housing in operable communication with the chamber door to release the chamber door from a closed position; a secondary unlock input attached to the housing to selectively direct the chamber door to an unlocked state; as well as a controller in operable communication with the control panel, the controller being configured to direct a door monitoring operation including: initiating a locking condition in which the chamber door is directed to a locked state according to a predetermined time period in which the chamber door requires a multi-step opening procedure, Prior to expiration of the predetermined time period, determining a headroom chamber status, determining the headroom chamber status comprising receiving a headroom chamber signal, and Prior to expiration of the predetermined time period, in response to determining a clear chamber condition, an unlock condition is initiated wherein the locking condition ceases and the chamber door remains in the unlocked state, thereby allowing a single-step opening sequence at the primary door input.

2. The microwave oven device according to claim 1, wherein: Receiving the clear chamber signal includes receiving an input signal at the secondary unlock input.

3. The microwave oven device according to claim 2, wherein: Determining the clear chamber state further includes detecting a door closing event after initiating the lock condition.

4. The microwave oven device according to claim 1, wherein: Receiving the clear cavity signal includes receiving a detection signal from a presence sensor mounted within the cooking cavity, the detection signal corresponding to an empty state of the cooking cavity.

5. The microwave oven device according to claim 1, wherein: The door monitoring operation also includes Prior to the predetermined period of time, a heating cycle is initiated wherein the heating element is directed to an active state to heat one or more items within the cooking cavity.

6. The microwave oven device according to claim 5, wherein: The door monitoring operation also includes Determine the expiration of the heating cycle, Wherein the lockout condition is initiated based on a heating cycle and continues after it is determined that the heating cycle has expired.

7. The microwave oven device according to claim 1, wherein: The predetermined time period is approximately 30 minutes.

8. The microwave oven device according to claim 1, wherein: The primary door input includes a slidable button.

9. The microwave oven device according to claim 1, wherein: The primary door input includes a pull handle.

10. The microwave oven device according to claim 1, further comprising: A door lock in mechanical communication with the chamber door, the door lock being movable between a locked state that restricts movement of the chamber door from the closed position and an unlocked state that permits movement of the chamber door from the closed position.

11. A method for operating a microwave oven device, the microwave oven device comprising a cabinet, a control panel and a chamber door, the method comprising: initiating a locking condition in which the chamber door is directed to a locked state according to a predetermined time period in which the chamber door requires a multi-step opening procedure, Prior to expiration of the predetermined time period, determining a headroom chamber status, determining the headroom chamber status comprising receiving a headroom chamber signal, and Prior to expiration of the predetermined time period, in response to determining a clear chamber condition, an unlock condition is initiated wherein the locking condition ceases and the chamber door remains in the unlocked state, thereby allowing a single-step opening sequence at the primary door input.

12. The method according to claim 11, wherein: Receiving the clear chamber signal includes receiving an input signal at a secondary unlock input.

13. The method according to claim 12, wherein: Determining the clear chamber state further includes detecting a door closing event after initiating the lockout condition.

14. The method according to claim 11, wherein: Receiving the clear cavity signal includes receiving a detection signal from a presence sensor mounted within the cooking cavity of the microwave oven apparatus, the detection signal corresponding to an empty state of the cooking cavity.

15. The method according to claim 11, further comprising: Prior to the predetermined period of time, a heating cycle is initiated wherein the heating element is directed to an active state to heat one or more items within the cooking cavity of the microwave apparatus.

16. The method according to claim 15, further comprising: Determine the expiration of the heating cycle, Wherein the lockout condition is initiated based on a heating cycle and continues after it is determined that the heating cycle has expired.

17. The method according to claim 11, wherein: The predetermined time period is approximately 30 minutes.

18. The method according to claim 11, wherein: The primary door input includes a slidable button.

19. The method according to claim 11, wherein: The primary door input includes a pull handle.

20. The method according to claim 11, wherein: The microwave oven apparatus further includes a door lock in mechanical communication with the chamber door, the door lock being movable between a locked state restricting movement of the chamber door from the closed position and an unlocked state allowing movement of the chamber door from the closed position.

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