Patent Publication Number: US-9854628-B2

Title: Over-the-range microwave oven and method of using the same

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims benefit and priority to Korean Patent Application No. 10-2014-0174473, filed on Dec. 5, 2014, with the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference. 
     TECHNICAL FIELD 
     Embodiments of the present disclosure relate to over-the-range microwave ovens, and more specifically, relate to humidity sensing mechanisms of over-the-range microwave ovens. 
     BACKGROUND 
     In general, an over-the-range microwave oven refers to a microwave oven equipped with a venting system for exhausting heat, air and/or fumes during cooking. An over-the-range microwave oven is usually mounted above a gas or electric range. 
     That is, a typical over-the-range microwave oven may include a cooking unit and a duct unit. The cooking unit is used to heat food or liquid (hereinafter, collectively referred to as food) placed therein using microwave energy. 
     During microwave cooking, water vapor is generated from the food being heated. The humidity of food can be sensed by a humidity sensor in the microwave. The sensed humidity may be utilized for controlling the operation of the cooking unit. 
     Usually, a humidity sensor is installed on the upper side of the cooking unit and operates to sense of the amount of water vapor inside the cooking unit. 
     However, because the motion of water vapor generated from food tends to be affected by the air flow induced by the air discharge unit of the microwave oven, the information sensed by the humidity sensor cannot accurately reflect the cooking condition of the food or the working condition of the cooking unit. 
     SUMMARY 
     Embodiments of the present disclosure are directed to providing an over-the-range microwave oven that can sense the humidity inside the cooking unit with enhanced accuracy. 
     An exemplary embodiment of the present disclosure provides an over-the-range microwave oven design including: a housing; a cooking unit which is disposed in the housing; a duct unit which is disposed in the housing; a first panel which divides the duct unit into an upper duct and a lower duct; at least a pair of second panels which forms both lateral side surfaces of the upper duct; and a humidity sensor which is disposed on the first panel. 
     In addition, the housing may include a partition wall which vertically partitions the interior of the housing into the cooking unit and the duct unit and has a water vapor discharge portion through which water vapor flows out of the cooking unit. The duct unit may include an upper duct unit which is disposed between the housing and the cooking unit and is located on an upper side of the cooking unit, the first panel may be spaced apart from an upper side of the partition wall and may form a bottom surface of the upper duct unit. The duct unit may further include the second panels disposed between the first panel and the housing which form the lateral side surfaces of the upper duct unit. An interval or a gap between the second panels decreases along an air flow direction. A humidity sensor may be disposed on the first panel so as to be spaced apart from one of the second panels. 
     In addition, the over-the-range microwave oven may include: a third panel which is disposed on the rear side of the pair of second panels and has an inlet hole into which air flows; and a fourth panel which is disposed outside one panel of the pair of second panels. 
     One of the second panels and the fourth panel may extend to enclose a portion between the first panel and the partition wall. 
     The humidity sensor may be disposed in a space defined by one of the second panels and the fourth panel. 
     In addition, the pair of second panels may include: a pair of first horizontal portions which is disposed at both sides of the third panel, respectively, and parallel with each other; a pair of inclined portions which is extended from the pair of first horizontal portions, respectively, and that has an interval or a gap therebetween that is gradually decreased; and a pair of second horizontal portions which is extended from the pair of inclined portions, respectively, and parallel with each other. 
     In addition, the fourth panel may be disposed so that a space formed by the fourth panel, the inclined portion, and the second horizontal portion is symmetric in shape. 
     In addition, a space (which is defined by one of the second panels and the fourth panel) may be formed above the water vapor discharge portion. 
     In addition, the humidity sensor may be disposed above the water vapor discharge portion. 
     Another exemplary embodiment of the present disclosure provides an over-the-range microwave oven including: a housing which includes a partition wall which vertically partitions the interior of the housing into a cooking unit and a duct unit and has a water vapor discharge portion through which water vapor flows out of the cooking unit; the cooking unit which is disposed in the housing; the duct unit which includes an upper duct unit which is disposed between the housing and the cooking unit and is disposed at an upper side of the cooking unit; a first panel which is spaced apart from an upper side of the partition wall and forms a bottom surface of the upper duct unit; a pair of second panels which is disposed between the first panel and the housing to form lateral side surfaces of the upper duct unit and formed such that an interval or a gap therebetween is decreased in a direction from a portion (into which air flows) toward a portion where air is discharged; and a duct module which includes a humidity sensor that is disposed on the first panel, disposed outside the pair of second panels, and disposed on the first panel so as to be spaced apart from one of the second panels. 
     The over-the-range microwave oven may include: a third panel which is disposed at the rear of the pair of second panels and has an inlet hole into which air flows; and a fourth panel which is disposed outside one of the pair of second panels. 
     One of the second panels and the fourth panel may extend to enclose a portion between the first panel and the partition wall. 
     The humidity sensor may be disposed in a space defined by one of the second panels and the fourth panel. 
     The pair of second panels may include: a pair of first horizontal portions which is disposed at both sides of the third panel, respectively, and parallel with each other; a pair of inclined portions which is extended from the pair of first horizontal portions, respectively, and has an interval or gap therebetween that is gradually decreased; and a pair of second horizontal portions which is extended from the pair of inclined portions, respectively, and parallel with each other. 
     The duct module may include: a power source unit which is disposed on the first panel outside one of the first horizontal portions; a running capacitor which is disposed on the first panel outside one of the inclined portions; a noise filter which is disposed on the first panel outside one of the second horizontal portions; and a fuse which is disposed on the first panel outside the other first horizontal portion. 
     The duct module may further include a lighting unit which is disposed on a lower surface of the first panel. The partition wall may have a light entering portion through which light from the lighting unit enters the cooking unit. 
     A filter may be disposed on the pair of second horizontal portions. 
     The over-the-range microwave oven may further include an air discharge unit which is disposed between the third panel and a rear surface of the housing and allows air to flow to the duct unit. 
     In addition, the air discharge unit may include an air discharge motor, and an impeller which is operated by the air discharge motor and allows air to flow to the duct unit. 
     In addition, the third panel may include a first inlet hole, and a second inlet hole, and the impeller may include a first impeller which is disposed at one side of the air discharge motor to allow air to flow into the first inlet hole, and a second impeller which is disposed at the other side of the air discharge motor to allow air to flow into the second inlet hole. 
     The third panel may further include a bent portion which protrudes forward between the first inlet hole and the second inlet hole. 
     Yet another exemplary embodiment of the present invention provides a method of using an over-the-range microwave oven, including: operating an air discharge unit; and discharging air, by using the discharge unit, around a gas range or discharging air flowing by a drive unit of a microwave oven through an upper duct unit, which is disposed between a housing and a cooking unit and forms a flow path, the duct unit including a first panel which is disposed at an upper side of the cooking unit, a pair of second panels which is disposed between the first panel and the housing and disposed symmetrically so that an interval or a gap therebetween is decreased toward the front side, and a third panel which is disposed at the rear of the pair of second panels and has inlet holes into which air flows. An operational state of the cooking unit is controlled in accordance with humidity sensed by a humidity sensor disposed on the first panel. 
     The present disclosure improves ventilation efficiency and air flow efficiency by improving the duct flow path. The duct module integrates the associated electrical components in a compact manner, which improves space usage efficiency of the oven, reduces assembly tolerance, improves manufacturing productivity, improves durability, and facilitates development of compact style over-the-range ovens. 
     The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates the configuration of an exemplary over-the-range microwave oven design according to an embodiment of the present disclosure. 
         FIG. 2  illustrates a top view of an exemplary first panel on which a duct module is mounted according to an embodiment of the present disclosure. 
         FIG. 3  illustrates the first panel illustrated in  FIG. 2  viewed from the lower side thereof. 
         FIG. 4  illustrates a view with the upper duct unit illustrated in  FIG. 2  removed. 
         FIG. 5  is a cross-sectional view of an exemplary over-the-range microwave oven according to an embodiment of the present disclosure taken along line A-A′ of  FIG. 2 . 
     
    
    
     DETAILED DESCRIPTION 
     In the following detailed description, reference is made to the accompanying drawing, which forms a part hereof. The illustrative embodiments described in the detailed description, drawing, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented here. 
     Hereinafter, an exemplary embodiment of the present disclosure will be described in detail with reference to the accompanying drawings. 
     Unless particularly defined otherwise, all terms used in the present specification are the same as general meanings of the terms understood by those skilled in the art, and if the terms used in the present specification conflict with general meanings of the corresponding terms, the meanings of the terms comply with the meanings defined in the present specification. 
     However, the present disclosure, which is disclosed below, is intended to merely describe the exemplary embodiment of the present disclosure, but is not intended to limit the scope of the present disclosure, and like reference numerals designate like elements throughout the specification. 
       FIG. 1  illustrates a perspective view of an exemplary over-the-range microwave oven according to an embodiment of the present disclosure in which an upper housing and a lateral side housing are removed.  FIG. 2  is a top view of a first panel on which a duct module is mounted according to the exemplary embodiment of the present disclosure.  FIG. 3  is a view of the first panel illustrated in  FIG. 2  viewed from the lower side thereof.  FIG. 4  is a view in which an upper duct unit illustrated in  FIG. 2  is removed.  FIG. 5  is a cross-sectional view of an exemplary over-the-range microwave oven according to an embodiment of the present disclosure taken along line A-A′ of  FIG. 2 . 
     Referring to  FIGS. 1 and 2 , the microwave oven includes a housing  100 , a cooking unit  200 , a duct unit  300 , an air discharge unit  400 , and a duct module  600 , and may further include a filter unit  500 . 
     The housing  100  defines the exterior of the over-the-range microwave oven, and may be made of a metal or nonmetal material. The housing  100  may include an upper cover and a lateral side cover (not illustrated), a rear cover  110  and a lower cover  120 . The respective covers  100  may be integrally formed or may be detachably coupled to each other. 
     In addition, the housing  100  further includes a partition wall  130  which may vertically partition the interior of the housing  100  into the cooking unit  200  and the duct unit  300 . The partition wall  130  may be formed integrally with the housing  100 , or may be fastened to the housing  100 , e.g., by bolting. 
     Here, the partition wall  130  may have a water vapor discharge portion  131  through which water vapor flows out of the cooking unit  200 , and a light entering portion  132  through which light generated from a lighting unit  660  enters the cooking unit  200 , as described below. 
     The water vapor discharge portion  131  or the light entering portion  132  may be formed by drilling a plurality of holes into the partition wall  130 . In particular, in the case in which the light entering portion  132  includes a plurality of holes, the light entering portion  132  may be covered by glass or a transparent film such that all of the water vapor generated in the cooking unit  200  will flow into the water vapor discharge portion  131 . 
     In addition, the housing  100  may be formed as an outer wall of the duct unit  300  as described below. 
     The cooking unit  200  is disposed in the housing  100 , and may include a cooking chamber, and an electric equipment chamber. 
     The door  210  is disposed in the front of the cooking chamber. The door  210  may be hingedly coupled to the housing  100 . A handle  211  may be disposed on the door  210  which allows a user to easily open and close the door  210 . In addition, in order to allow the user to easily view the interior of the cooking chamber, the door  210  may further include a transparent window  212 , e.g., made of tempered glass, etc. 
     In addition, the cooking unit  200  may include a control panel  220  disposed on one side of the door  210 . The control panel  220  may include input mechanisms (such as buttons, a touch panel, or a dial) for users to control the cooking unit  200 . The control panel  220  may include a display unit  221  for presenting information to users related to the operations of the over-the-range microwave oven. 
     In addition, the control panel  220  may include buttons, a touch panel, or a dial, which allow the user to control the operations of the duct unit  300  and the cooking unit  200 . The state of the interior of the cooking unit  200  can be sensed by a humidity sensor  650  as described below. 
     The duct unit  300  may be disposed between the housing  100  and the cooking unit  200  and forms an air flow path. In this example, the duct unit  300  is divided into an upper duct unit  300  and a lateral side duct unit  320 . 
     The lateral side duct unit  320  is disposed between the cooking unit  200  and the side cover (not illustrated) or may be disposed between the control panel  220  and the side cover (not illustrated). In this case, the housing  100  serves as the outer wall of the duct unit  300 . 
     Here, the lateral side duct unit  320  includes a first inlet port  321  having an opening at the lower cover  120  for accepting air from the outside of the oven. The lateral side duct unit  320  guides air flowing from the first inlet port  321  to the upper duct unit  300 . A plurality of first inlet ports  321  may be formed similarly. 
     The upper duct unit  310  is disposed on an upper side of the cooking unit  200  and may include a first panel  311 , second panels  312 , and/or a third panel  313 , and may further include a fourth panel  314 . 
     By use of the upper duct unit  300 , an air discharge flow path (or the exhaust path) from the rear side towards the front side is formed. Thus, a range hood and an over-the-range microwave oven according to the present disclosure may advantageously reduce turbulent air flows, electric power consumption, and noise level. 
     The first panel  311  divides the duct unit  300  into an upper duct and a lower duct. 
     More specifically, the first panel  311  may be disposed in the housing  100  to form a bottom surface of the upper duct unit, and may be disposed on an upper side of the cooking unit  200  and on an upper side of the partition wall  130 . The first panel  311  may be integrally formed as an upper surface of the partition wall  130 . Alternatively, the first panel  311  may be disposed to be spaced apart from the upper side of the partition wall  130 . Alternatively, a part of the partition wall  130  may be recessed downward, such that the partition wall  130  may be spaced apart from the first panel  311 . 
     In addition, the first panel  311  includes second inlet ports  311   a  (in the rear side) through which air flowing from the lateral side duct unit  320  flows into the upper duct unit  310 . The second inlet ports  311   a  may be formed on both sides of the back of the first panel  311 , respectively, and correspond to a first impeller  411  and a second impeller  412  as described below. 
     The first panel  311  may be made of metal or plastic, for example. 
     Two second panels  312  are disposed as a pair between the first panel  311  and the housing  100  and form both lateral side surfaces of the upper duct unit, thereby partitioning the interior of the upper duct unit  310 . 
     The gap between the pair of second panels  312  may be designed to decrease along the air flow direction. More specifically, the pair of second panels  312  may be symmetrically disposed and the gap therebetween increasingly narrows toward the front side. 
     According to the present disclosure, in order to effectively contain water vapor generated from food within he cooking unit such that the humidity sensor  650  can accurately detect humidity therein, one of the pair of second panels  312  may extend downward to enclose a region between the first panel  311  and the partition wall  130 . 
     More specifically, the pair of second panels  312  includes a pair of first horizontal portions  312   a  disposed on both sides of the third panel  313  (as described below) and in parallel to each other. The second panels  312  further include a pair of inclined portions  312   b  extending from first horizontal portions  312   a  and having an increasingly smaller gap. The second panels  312  further include a pair of second horizontal portions  312   c  extending from the inclined portions  312   b  and disposed in parallel to each other. 
     According to the present disclosure, the air flow path has a symmetrical geometry and becomes narrower toward the front side. The flow path may advantageously improve flow efficiency of the exhaust air or fumes discharged compared to the related art, and may reduce the noise level. 
     Here, a connecting surface between the first horizontal portion  312   a  and the inclined portion  312   b  (or a connecting surface between the inclined portion  312   b  and the second horizontal portion  312   c  may be tapered or rounded), thereby forming an air discharge flow path offering enhanced ventilation efficiency. 
     The third panel  313  is disposed in the rear of the pair of second panels  312 , and may have inlet holes  313   aa  and  313   ab  for air flow. 
     That is, referring to  FIG. 3 , in the air discharge flow path according to the exemplary embodiment, air may pass through the first inlet port  321 , the second inlet ports  311   a  and to the impellers  411  and  412  (which redescribed below), and may flow into the inlet holes  313   aa  and  313   ab . The air flow is then discharged to the outside through a flow path formed by the first panel  311 , the second panels  312 , and the upper cover  100 . 
     In addition, the third panel  313  may include the first inlet hole  313   aa  directing to the first impeller  411 , and the second inlet hole  313   ab  directing to the second impeller  412 , thereby effectively enhancing the various air flows. 
     In addition, the third panel  313  may further include a bent portion  313   b  formed between the first inlet hole  313   aa  and the second inlet hole  313   ab  and protruding forward, thereby further enhancing the air flow. 
     To prevent the formation of turbulance, the bent portion  313   b  may be increasingly narrower toward the front side. For example, the bent portion  313   b  may have a trapezoidal shape. 
     The fourth panel  314  may be disposed outside one of the pair of second panels  312 . The fourth panel  314  encloses a zone in which the humidity sensor  650  is disposed. Thus, water vapor within the cooking unit  200  is unaffected by air flow that is present outside the cooking unit  200 . Thereby, the humidity sensor  650  can accurately sense the humidity within the cooking unit. 
     In this example, the fourth panel  314  extends downward such that the region between the first panel  311  and the partition wall  130  is enclosed. 
     Referring to  FIG. 5 , in the exemplary embodiment having the aforementioned features, the water vapor flow is restricted to the path formed by the cooking unit  200 , the water vapor discharge portion  131 , the pair of second plates  312 , and the fourth plate  314 , and a discharge port at the front side. 
     The air discharge unit  400  is disposed between the third panel  313  and the rear surface of the housing  100 , and allows air to flow into the inlet holes  313   aa  and  313   ab . More specifically, the air discharge unit  400  may include an air discharge motor  410 , and the impellers  411  and  412 . The impellers  411   412  are driven by the air discharge motor  410  and allow air to flow into the inlet holes  313   aa  and  313   ab.    
     Here, the first impeller  411  is disposed on one side of the air discharge motor  410 . The second impeller  412  is disposed on the other side of the air discharge motor  410 . Both ends of the first impeller  411  and the second impeller  412  are disposed proximate to second inlet ports  311   a , respectively, thereby allowing air to be pumped from the outside to the inside of the housing  100 , to the first panel  311 , and to the second panels  312 . 
     According to embodiments of the present disclosure, because the upper duct unit  310  is configured to be narrower toward the front side as described above, the functional components associated with the duct unit  300  may be arranged in a compact manner as a duct module  600 . 
     Here, the duct module  600  may include a power source unit  610 , a running capacitor  620 , a noise filter  630 , and a fuse  640 , and may further include the humidity sensor  650  or the lighting unit  660 . 
     The power source unit  610  can be connected to wall power and distribute electric power for operating the cooking unit  200  or the duct unit  300 . The power source unit  610  may be disposed on the first panel  311  outside one of the first horizontal portions  312   a.    
     The running capacitor  620  (also commonly referred to as a “starting condenser”) is used to provide the initial power for activating the air discharge motor  410 . The running capacitor  620  may be disposed on the first panel  311  outside one of the inclined portions  312   b.    
     The noise filter  630  serves to reduce noise caused by operating the air discharge motor  410 , and to provide related signals. The noise filter  430  may be disposed on the first panel  311  outside one of the second horizontal portions  312   c.    
     The fuse  640  functions to shut off electric power supplied from the power source unit  610 , when an excessive amount of heat (for example, about 90° C. or 150° C.) is generated in the cooking unit  200 , or when overheating of the air discharge motor  410  is sensed. The fuse  640  may be disposed on the first panel  311  outside the other first horizontal portion  312   a.    
     The humidity sensor  650  may be disposed on the first panel  311 . The humidity sensor  650  senses humidity or temperature of water vapor generated from food being cooked in the cooking unit  200 . Accordingly, the humidity sensor transmits a signal to a control unit (not illustrated) to control the cooking unit  200  or generating a signal for automatically turning on and off the air discharge motor  410 . 
     The humidity sensor  650  serves to sense humidity of water vapor generated in the cooking unit  200 , and generally needs to be disposed above the cooking unit  200 . The duct module  600  may be disposed on the first panel  311  outside the other inclined portion  312   b  and the other second horizontal portion  312   c.    
     To facilitate the humidity sensor  650  to function properly, the microwave oven may further include the fourth panel  314  disposed on the first panel  311 . The combination of the fourth panel  314 , the other inclined portion  312   b , and the other second horizontal portion  312   c  define a symmetric region. The humidity sensor  650  may be disposed within this region. 
     That is, the humidity sensor  650  may be disposed on the first panel so as to be spaced apart from one of the second panels  312 . 
     More specifically, the humidity sensor  650  may be disposed within a region defined by one of the second panels  312  and the fourth panel  314 . This region may be located above the water vapor discharge portion  131 . In order to accurately sense a state in the cooking unit  200 , the humidity sensor  650  may be disposed above the water vapor discharge portion  131 . 
     Because the duct unit is closed above the water vapor discharge portion  131 , the humidity sensor  650  may accurately detect the state of food being cooked in the cooking unit  200 . The humidity sensor  650  is coupled to the aforementioned control panel  220  and can provide information used to control the operation of the cooking unit  200 . 
     The lighting unit  660  is disposed on a lower surface of the first panel  311 , and allows observation of the interior of cooking unit  200  without opening the door. To this end, the light entering portion  132  may be formed in the partition wall  130  to allow light into the cooking unit  200 . 
     Because the components associated with operating the duct unit are modularized and integrated onto the first panel  311 , the related assembly tolerance is advantageously reduced, which can improve manufacturing productivity. The reduced assembly tolerance requirements may also facilitate development of over-the-range microwave ovens of smaller sizes. 
     Further, the configuration of the duct unit according to the present disclosure enables an accurate detection of the state of the cooking unit  200  by the humidity sensor  650 . 
     The filter unit  500  may be disposed on the front side of the pair of second panels  312 , and more specifically, on the second horizontal portion  312   c . The filter unit  500  may be a charcoal filter and can serve to filter air before it is discharged outside. The filter unit  500  may be detachable. 
     An exemplary method of using the over-the-range microwave oven design according to an embodiment of the present disclosure will be described below. 
     First, the air discharge unit  400  is activated when a user provides input through the input means associated with the microwave oven, e.g., the buttons, the touch panel, or the dial disposed on the control panel  220 . 
     Then, the air discharge motor  410  is activated once the external electric power is supplied. The motor  410  drives the impellers  411  and  412  to rotate, and thereby the outside air is drawn to the oven from the first inlet port  321  of the lateral side housing. The drawn air flows into the impellers  411  and  412  through the second inlet ports  311  disposed on the first panel  311 . 
     Thereafter, air flow exits the impellers  411  and  412  at a high speed and enters into a duct through the inlet holes  313   aa  and  313   ab  of the third panel  313 . The duct is formed by the housing  100 , the first panel  311 , and the second  312 . 
     In this example, the bent portion  313   b  formed on the third panel  313  guides the air flow toward the front side and can advantageously prevent the formation of turbulent flow from air exiting the impellers  411  and  412 . Because the second panels  312  have a symmetric geometry and form an increasingly narrower gap, air flow can be quickly discharged outside. 
     The filter is disposed between the second horizontal portions  312   c  and at the the narrowest location of the flow path, thereby effectively capturing and filtering contaminants. 
     That is, by the operation of the air discharge unit  400 , hot air or fumes around a gas or electric range may be discharged or air flowing by a drive unit of a microwave oven may be discharged through the upper duct unit  300 . The upper duct unit  300  is disposed between the housing  100  and the cooking unit  200  and serves as a flow path. The upper duct unit includes the first panel  311  disposed on the upper side of the cooking unit  200 , the pair of second panels  312  disposed between the first panel  311  and the housing  100 . The second panels are disposed symmetrically and a gap therebetween decreases toward the front side. The upper duct unit  300  further includes the third panel  313  disposed in the rear of the pair of second panels  312  and having the inlet holes  313   aa  and  313   ab  for air flow. 
     Embodiments of the present disclosure employ an air discharge unit  400  disposed on the rear side and configured to guide air from the rear side toward the front side. The air discharge unit  400  includes a symmetric flow path which is increasingly narrower toward the discharge port to further increase the aforementioned effects. 
     From the foregoing, it will be appreciated that various embodiments of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various embodiments disclosed herein are not intended to be limiting, with the true scope and spirit being indicated by the following claims.