Abstract:
A combination microwave ventilated hood cooking system including a microwave oven with a cooking cavity; a magnetron for generating microwaves located adjacent the cooking cavity; and cooling fan outside the cooking cavity. The cooking cavity including at least two trays of different shapes and a stirrer for dispersing microwaves in the cooking cavity. A guide is between the stirrer and the cooling fan such that the guide has a downward slope from the cooling fan to the stirrer. During operation of the microwave, the cooling fan creates an air current, which is directed to the stirrer by the guide and drives the stirrer to disperse microwaves in the cooking cavity and direct an air current to cool the magnetron.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a combination ventilated hood and microwave oven, and more particularly, to a combination ventilated hood and microwave oven having a plurality of trays by which a large quantity of food is cooked at the same time. 
     2. Description of the Background Art 
     A general combination microwave oven and ventilated hood has a function of suctioning steam and smoke generated during the operation of a gas oven range positioned at a lower portion of the microwave oven. 
     The interior of a combination ventilated hood and microwave oven in the conventional art, as illustrated in FIG. 1, includes a cavity  102 , which is a cooking space for cooking foodstuffs by microwaves oscillated from a magnetron  106 . Usually, since the cavity  102  of the combination ventilated hood and microwave oven is installed across the width of an upper portion of the gas oven range, the horizontal length L of the cavity  102  is large as compared to the general stand alone microwave oven. Also, an exhaust motor  104  is installed in the cavity  102  to exhaust steam and smoke. 
     At the bottom surface of the cavity  102 , a circular rotary tray  108  for putting foodstuffs to be cooked on the top surface thereof, is installed. In addition, a rotary tray mounting unit  107  is connected to a lower portion of the rotary tray  108  so that the rotary tray  108  is mounted for rotation. 
     The rotary tray mounting unit  107  is positioned at the bottom surface of the cavity  102  and includes a driving source  103  with a power transmission device for rotating the rotary tray  108 . 
     However, in the conventional combination ventilated hood and microwave oven, the rotary tray  108  is installed at the center portion of the bottom surface of the cavity  102 , and the rotary tray mounting unit  107  for rotating the rotary tray  108  is also installed at a lower side of the center portion of the bottom surface of the cavity  102 . 
     Namely, in the conventional ventilated hood and microwave oven, although the horizontal length L of the cavity  102  is large as compared to the general microwave oven, the rotary tray  108  is mounted at the central portion of the cavity  102  in the same manner as the general microwave oven. 
     Therefore, in the conventional microwave oven and ventilated hood, the right and left side portions of the rotary tray in the cavity are not used as a cooking space. Also, although the size of the inner space of the cavity is large as compared to the general microwave oven, the actual space for putting foodstuffs thereon for cooking purposes has the same size as the general microwave oven, resulting in an inefficient use of the cooking space. 
     Meanwhile, as illustrated in FIG. 2, another microwave structure according to the conventional art is disclosed. The structure includes a first tray  210  and a second tray  220  each having a smaller size than the above-described rotary tray. The first tray  210  is installed at one side of the rotary tray (not shown) and the second tray  220  is installed on the other side of the rotary tray. Both the first tray  210  and the second tray  220  are to be driven by a motor  330  for driving the rotary tray. 
     Also, the structure includes a main gear  201  connected to the motor  330  for driving the rotary tray; a first slave gear  211  for driving the first tray  210  engaged with the main gear  201 ; a second slave gear  221  for driving the second tray  220  is engaged with the main gear  201  and opposite the first slave gear  211 ; and the axis of the motor  310  extends from the motor through the main gear  201 . Further, although not shown, the structure has a third tray. 
     However, although the above-described structure can have three trays, the rotary tray alone is driven during actual operation of the microwave oven. As illustrated in FIG. 2, only the first tray  201  and the second tray  202  must be driven in a state where the rotary state is escaped to the outside of the main frame. Consequently, there occurs a problem that the manufacturing cost is increased, and the space of a cooking chamber is not efficiently used. 
     Meanwhile, FIG. 3 illustrates still another structure according to the conventional art. The structure includes a stirrer fan  312  driven by the motor  307  is installed at one side of the rotary tray  305 , and a base plate  319  on which a container  318  for containing a temperature probe  320  can be put on is installed at an upper side of the stirrer fan  312 . Thereby, it is possible to simultaneously carry out cooking using the rotary tray  305  and cooking using the temperature probe  320 . 
     The driving structure of the stirrer fan  312  driven by the motor  307  will now be described. The rotating shaft  306  of the rotary tray  305  is connected to the rotating shaft  308  of the motor  307 . A pulley  314  fixed to the rotating shaft  313  of the stirrer fan  312  and a pulley  315  fixed to the rotating shaft  308  of the motor  307  are connected with a belt  316 , thereby making it possible for the stirrer fan  312  to be driven by the motor  307 . 
     In addition, a wave guide  317  for transmitting microwaves generated from the magnetron  309  to the stirrer fan  312  is installed at one side wall of the cavity  302 , while a shelf-shaped base plate  319  for putting the temperature probe  320  on the top surface thereof is positioned at an upper side portion of the stirrer fan  312  at one side of the rotary tray  305 . Reference numeral  321  designates a bracket for fixing the motor. 
     However, in addition to the wave guide  310  installed at an upper portion of the cavity  302 , the wave guide  317  has to be installed in order to transmit microwaves to the stirrer fan  312  positioned at a lower portion of the cavity  302 . Thus, the wave guide must be longer and accordingly increases the manufacturing cost. 
     In addition, the bottom surface of the base plate  319  is positioned higher, than the bottom surface of the rotary tray  305 . Thus, making it inconvenient to clean the microwave oven and aggravating the aesthetic appearance of the microwave oven. 
     In addition, since the pulleys and belt are required for driving the stirrer fan, the manufacturing cost is increased. In particular, the diameter ratio of the pulley fixed to the rotating shaft of the motor for properly rotating the stirrer fan for cooking purposes to the pulley fixed to the rotating shaft of the stirrer fan must be increased, thus making the manufacturing process complicated and increasing the manufacturing cost. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is an object of the present invention to provide a combination ventilated hood microwave oven having a plurality of trays and able to cook a large quantity of food at one time by making the most of a cooking space of the combination ventilated hood and microwave oven. 
     It is another object or me present invention to provide a combination ventilated hood and microwave oven having a plurality of trays by which microwaves supplied into a cavity can be uniformly penetrated through foodstuffs to be cooked. 
     To achieve the above objects, there is provided a combination microwave oven and ventilated hood having a plurality of trays which includes: a stirrer fan installed at an upper portion of the cavity at which the plurality of trays are installed; a coding fan installed at an upper portion of a machine chamber formed at one side of the cavity; and a guide unit for guiding parts of an airflow generated from the cooling fan towards the stirrer fan. Additional advantages, objects and features of the invention will become more apparent, from the description which follow. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will become better understood with reference to the accompanying drawings which are given only by way of illustration and thus are not limitative of the present invention, wherein: 
     FIG. 1 depicts a cross-sectional view of a combination ventilated hood and microwave oven according to the conventional art; 
     FIG. 2 depicts a partial cross-sectional view of another example of a combination ventilated hood and microwave oven according to the conventional art; 
     FIG. 3 depicts a partial cross-sectional view of still another example of a combination microwave oven and ventilated hood according to the conventional art; 
     FIG. 4 depicts a cross-sectional view of a combination ventilated hood and microwave oven having a plurality of trays according to a first embodiment of the present invention; 
     FIG. 5 depicts a top cross-sectional view of, the combination ventilated hood and microwave oven according to the first embodiment of the present invention as depicted in FIG. 4; 
     FIG. 6 depicts part of the construction of the combination ventilated hood and microwave oven having a plurality of trays according to the first embodiment of the present invention; 
     FIG. 7 depicts a partial vertical cross-sectional view of the construction of a driving apparatus for the combination ventilated hood and microwave oven having a plurality of trays according to the first embodiment of the present invention; and 
     FIG. 8 depicts a top cross-sectional view of a combination microwave oven and ventilated hood having a plurality of trays according to a second embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention includes a combination ventilated hood and microwave oven. As depicted in FIG. 4, the microwave oven includes a first tray mounting unit  12  for putting a first tray  12   a  on the top surface thereof and a second tray mounting unit  14  for putting a second tray  14  on the top surface thereof are installed. 
     The first tray mounting unit  12  is installed at a side portion in the cavity  10 , for example, at a position most adjacent to the utmost left side in the cavity  10 . The second tray mounting unit  14  is installed at the other side portion in the cavity  10 , for example, at a position most adjacent to the utmost right side in the cavity  10 . 
     In addition, the first tray mounting unit  12  and the second tray mounting unit  14  are positioned at a space formed on the bottom surface of the cavity  10 , respectively. 
     In a first embodiment of the present invention, as illustrated in FIG. 5, the first tray mounting unit  12  is installed so that the first tray  12   a  of a circular shape can be mounted, and is constructed so that the first tray  12   a  is rotatable during operation of the microwave oven. Additionally, the first tray mounting unit  12  includes a driving source for rotating the first tray  12   a  and a power transmission device for transmitting power from the driving source to the tray. 
     That is, according to the first embodiment of the present invention, the first tray  12   a  is constructed as a circular tray that can be rotated by the first tray mounting unit  12 , which is of similar construction to a general microwave oven. 
     Meanwhile, in the first embodiment of the present invention, the second tray  14   a  is formed in a rectangular shape, and is constructed in such a manner that it is fixed to the second tray mounting unit  14 . 
     That is, in the cavity  10 , the second tray  14   a  is connected to an upper portion of the second tray mounting unit  14  and maintained in a fixed state where it is not rotated during the operation of the microwave oven. Therefore, foodstuffs put on an upper portion of the second tray  14   a  are cooked without rotation. 
     Also, in the combination microwave oven and ventilated hood of the present invention, a stirrer fan  40  for dispersing microwaves to be uniformly penetrated through foodstuffs when the microwaves oscillated from a magnetron  20  are introduced into the cavity  10  through a wave guide (not shown) is installed at the. upright upper portion of the second tray  14   a.    
     That is, the foodstuffs put on the top surface of the second tray  14   a  can be also uniformly cooked by the stirrer fan  40 . 
     In the second embodiment of the present invention, as illustrated in FIG. 8, the second tray  24  is a non-square shape, and can be formed to have a large area in a predetermined shape within the range where it does not contact the first tray  12   a . Further, the second tray  24  is installed to be rotatable during operation of the microwave oven, and the first tray  12   a  is installed in a fixed state during the operation of the microwave oven. 
     Hereinafter, the construction of the present invention is described in more detail, in particular, with respect to the stirrer fan  40 . 
     The stirrer fan  40  used in the combination ventilated hood and microwave oven having a plurality of trays of the present invention is not constructed to be rotated by a motor, but rather to be rotated by using parts of the flow of cooling air generated from the interior of the microwave oven. 
     As illustrated in FIG. 4, the magnetron  20  for supplying microwaves into the cavity  10  in which foodstuffs to be cooked is installed at a machine chamber  50  positioned at one side of the cavity  10 . 
     In addition, a cooling fan  30  for generating an air flow in order to cool the magnetron  20  and a high pressure trans (not shown) is installed at an upper portion of the machine chamber  50 . 
     In addition, the stirrer fan  40  is installed on the top surface of the cavity  10  adjacent to the machine chamber  50 . In detail, the stirrer fan  40  is installed to be rotatable at the inner side of a fan housing  42 , which is formed concave toward an upper portion of the case of the microwave oven on the top surface of the cavity  10 . 
     Accordingly, parts of an air flow generated by driving the cooling fan  30  to cool the magnetron  20  during operation of the microwave oven are guided towards the stirrer fan  40  for thereby driving the stirrer fan  40 . 
     At one side surface of the fan housing  42 , a plurality of air vents are formed so that air blowing from the cooling fan  30  can be passed through them. 
     Hereinafter, the construction for driving the stirrer fan  40  will be described. 
     As illustrated in FIG. 4, the cooling fan  30  installed at an upper end portion of the machine chamber  50  is installed higher than the stirrer fan  40 . 
     More specifically, at a lower portion of the cooling fan  30 , a guide  32  is extended to a part of the circumference of the cooling fan  30  in order to guide parts of the air flow generated from the cooling fan  30 . The air flow having collided with the guide  32  is guided through the interior of a guide duct  32   a  air-permeably connected to the guide  32 . 
     Continuously, the air flow guided through the interior of the guide duct  32   a  is introduced towards the stirrer fan  40  through the air vents  44  formed at one side surface of the fan housing  42 , and is contacted by the stirrer fan  40 . Thereby, the stirrer fan  40  is rotated. 
     The air flow that has rotated the stirrer fan  40  is discharged through the air vents  46  formed on the other side surface of the fan housing  42 . 
     In this manner, the air discharged through the fan housing  42  is mixed with air exhausted from a first exhaust unit  47  for exhausting air in the cavity  10 , and then is completely exhausted through a second exhaust unit  48  of a front grill of the combination ventilated hood and microwave oven. 
     Regarding the overall air flow formed according to the present invention, the air flow generated from the cooling fan  30  forms an air flow at least as far as the stirrer fan  40 , and thus, from a relatively upper position to a relatively lower position. 
     That is, in the present invention, because the cooing fan  30  is installed higher than the stirrer fan  40 , there is no portion moving upwardly in the path of the air flow guided from the cooling fan  30  to the stirrer fan  40 , resulting in decrease of energy toss due to path resistance. Therefore, the air flow colliding with the stirrer fan  40  has a high potential energy, and thus it is possible to rotate the stirrer fan  40  by much stronger power. 
     As described above, in the combination ventilated hood and microwave oven having a plurality of trays, a large quantity of food can be cooked at one time by making the most efficient use of a cooking space. Thereby, the overall cooking time is reduced. 
     Consequently, a wide variety of pairs of dishes can be cooked (for example, simultaneous warming up of bread and milk). 
     In addition, microwaves are uniformly penetrated through food put on a non-rotating tray without any additional motor during operation of the microwave oven. Thereby, the manufacturing cost and occurrence of failures of the microwave oven are reduced. 
     In addition, the cooling fan  30  is installed higher than the stirrer fan  40 , and accordingly the energy loss due to path resistance can be reduced, thereby reducing the maintenance cost during the operation of the microwave oven. 
     As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the meets and bounds of the claims, or equivalencies of such meets and bounds are therefore intended to be embraced by the appended claims.