Abstract:
A cooking apparatus having heaters and a cooking chamber defined in the cooking apparatus, the heaters are provided in the cooking chamber, and two or more buttons are provided representing different cooking temperatures. A temperature of the cooking chamber is set by pushing one of the two or more buttons. One of a plurality of cooking modes is selected depending on a kind of food, and each of the cooking temperatures is represented by one of the two or more buttons corresponds to each of the cooking modes. Therefore, setting various cooking temperatures depending on the kind of food is possible.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
   This application claims the benefit of Korean Application No. 2002-49329, filed Aug. 20, 2002, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a cooking apparatus, and more particularly, to a cooking apparatus having heaters. 
   2. Description of the Related Art 
   In general, a microwave oven is used to heat food by electromagnetic waves generated from a magnetron. Where the microwave oven is equipped with an additional heater, the microwave oven can further fulfill various cooking modes such as a baking function and a broiling function. 
   SUMMARY OF THE INVENTION 
   Accordingly, it is an aspect of the present invention to provide a cooking apparatus having heaters, which is provided with different setting buttons indicating representative set temperatures, so that a user can easily set a desired heating temperature to cook food by pushing one of the setting buttons is provided. 
   Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention. 
   In order to accomplish the above and other aspects, a cooking apparatus is provided comprising: a cooking chamber defined in the cooking apparatus; a heater provided in the cooking chamber; and two or more buttons representing different cooking temperatures; wherein a temperature of the cooking chamber is set by pushing one of the two or more buttons. 
   One of a plurality of cooking modes may be selected depending on a kind of food, and each of the cooking temperatures represented by the two or more buttons may correspond to each of the cooking modes. 
   The cooking apparatus may further include a keypad including numerical keys allocated with preset numeric characters, each of the numerical keys of the keypad representing a preset cooking temperature. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the preferred embodiments, taken in conjunction with the accompanying drawings of which: 
       FIG. 1A  is a cross-sectional view of a microwave oven having heaters; 
       FIG. 1B  is a view showing an input unit of the microwave oven shown in  FIG. 1A ; 
       FIG. 2  is a block diagram showing a microwave oven having heaters according to an embodiment of the present invention; 
       FIG. 3  is a view showing an input unit and a display unit of the microwave oven according to the embodiment of the present invention; and 
       FIG. 4  is a flow chart showing a method of controlling the microwave oven according to the embodiment of the present invention. 
       FIG. 5  is a microwave oven according to the embodiment of the present invention. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Reference will now made in detail to the present preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below in order to explain the present invention by referring to the figures. 
     FIG. 1A  shows a related microwave oven having a heater, invented by the same inventor as in the present invention, in which a door of the microwave is opened. As shown in  FIG. 1A , an electric component compartment  102  is provided therein with a magnetron  104  to generate electromagnetic waves. The magnetron  104  is supplied with electric power of very high voltage from an electric power supply  106 . 
   A cooking chamber  108  is provided at a bottom surface of the cooking chamber  108  with a glass tray  110 , which is used during cooking as electromagnetic waves generated from the magnetron  104  cook the food. The glass tray  110  is rotated by a motor  112 . The cooking chamber  108  is provided therein with an upper heater  124  and a pair of lower heaters  126  and  128 . The upper heater  124  is mounted on a ceiling of the cooking chamber  108  to radiate heat toward an upper surface of the food. A grill  120  is disposed below the upper heater  124 . The grill  120  is placed on grill supports  116   a  and  116   b  so as to be mainly used in broiling meats or fish. The pair of lower heaters  126  and  128  is disposed below the grill  120 . Disposed below the pair of lower heaters  126  and  128  is a plate  114 . The plate  114  is placed on plate supports  130   a  and  130   b  so as to be used in baking breads or biscuits. 
   The pair of lower heaters  126  and  128  is positioned between the grill  120  and the plate  114 . In the case of cooking the food by the grill  120 , the food, placed on the grill  120 , is heated at a lower surface of the food. In the case of cooking the food by the plate  114 , the food, placed on the plate  114 , is heated at an upper surface of the food. The lower heaters  126  and  128  are coupled to rotating members  126   a  and  128   a , respectively. Therefore, as the rotating members  126   a  and  128   a  are rotated, the pair of lower heaters  126  and  128  are rotated along with the rotating members  126   a  and  128   a , respectively. 
   In the above microwave oven, when there is a need to cook the food by the upper heater  124  and the pair of lower heaters  126  and  128 , a heating temperature of each of the heaters may be differently set depending on the kind of food. The heating temperature of each of the heaters  124 ,  126  and  128  may be set through manipulation of a keypad  103  of an input unit  100 . Further, the input unit includes an easy cleaning button  106  for setting a clean mode of the microwave oven, a start button  105  to start various operations of the microwave oven and a display  109  to display, for example, various temperature and time settings of the microwave oven.  FIG. 1B  shows the input unit  100  of the microwave oven in which the keypad  103  of the input unit  100  is provided with numerical keys, which indicate numeric characters “0”–“9”, respectively. In order to set a desired heating temperature, the numerical keys corresponding to a numerical value of the desired heating temperature are pushed by a user. For example, in order to set a temperature of 120° C., the numerical keys corresponding to numeric characters “1”, “2” and “0” may be sequentially manipulated. 
   This invention will be described in further detail by way of example with reference to  FIGS. 2 to 4  of the accompanying drawings. 
     FIG. 2  is a block diagram showing a microwave oven having heaters according to an embodiment of the present invention. As shown in  FIG. 2 , the microwave oven includes a control unit  202  to control an overall operation of the microwave oven. The control unit  202  is connected to an input unit  204 , a temperature-detecting unit  222  and a storage unit  206  at an input terminal of the control unit  202 . The input unit  204  is provided with an easy clean button, as shown in  FIG. 1B , as well as various keys such as numerical keys and mode selection keys, which allow a user to set a cooking mode and a time. The temperature-detecting unit  222  detects an inside temperature of a cooking chamber  20 , as shown in  FIG. 5 , and sends a temperature value of the cooking chamber  20  to the control unit  202 . The storage unit  206  stores data required to perform various cooking operations. 
   A magnetron-operating unit  208 , a motor-operating unit  212  and a heater-operating unit  218  are connected to an output terminal of the control unit  202 . The magnetron-operating unit  208  serves to drive a magnetron  210  to generate electromagnetic waves. The motor-operating unit  212  serves to drive a tray motor  214 , thereby rotating a tray  216  disposed in a cooking chamber  20 . The heater-operating unit  218  causes an upper heater  220  and lower heaters  226  and  228  to emit heat, in response to instructions of the control unit  202 . In particular, the heater-operating unit  218  controls not only heating conditions of the lower heaters  226  and  228 , but also rotating conditions of the lower heaters  226  and  228 . More specifically, when the microwave oven is operated in a cooking mode, rotating members  226   a  and  228   a  associated with the lower heaters  226  and  228  respectively, are rotated toward each other to cause the lower heaters  226  and  228  to be extended toward a center of the cooking chamber  20 . When the cooking mode is completed, the rotating members  226   a  and  228   a  are rotated in respective reverse directions to cause the lower heaters  226  and  228  to be returned to respective rest positions. 
     FIG. 3  shows an input unit of the microwave oven according to the embodiment of the present invention. As shown in  FIG. 3 , the input unit  204  of the microwave oven is provided with a keypad  302 , which includes numerical keys indicating temperature values increasing stepwise. Therefore, a user can easily set a temperature of the upper heater  220  and lower heaters  226  and  228  by pushing a numerical key indicating a desired temperature. 
   The input unit  204  is provided with not only a keypad  302 , a start button  304  and a stop button  306 , but also buttons (i.e., mode selection keys  308 ) to allow a user to select a cooking mode. The numerical keys comprising the keypad  302  are allocated with numeric characters “0”–“9” and numeric characters indicating 10 different temperature values increasing stepwise in a range of, for example, 40° C. to 220° C. The 10 numerical keys indicating the numeric characters “1 ”, “2”, “3”, . . . , “8”, “9” and “0” are allocated with corresponding temperature values of, for example “40° C.”, “100° C.”, . . . , “190° C.”, “205° C.” and “220° C.”, respectively. Further, a user can easily set a desired temperature of the upper heater  220  and lower heaters  226  and  228  by pushing one of the numerical keys indicating the desired temperature from among the 10 numerical keys. 
   In an operation of the microwave oven, when a user selects the cooking mode using the upper heater  220  and lower heaters  226  and  228  as in a baking or a broiling mode, the desired cooking temperature is set by pushing one of the numerical keys indicating the desired cooking temperature. More specifically, when a baking mode key of the mode selection keys  308  is selected to bake bread, the input unit  302  is automatically switched to a mode of setting the desired temperature, and one of the numerical keys in the keypad  302 , indicating the desired temperature, is pushed by the user. The set temperature is displayed on a display unit  224 . After the desired temperature is set, the input unit  204  is automatically switched to a mode of setting a cooking time. Thereafter, the user can set a desired cooking time by selecting numerical keys corresponding to the desired cooking time from among the numerical keys of “0”–“9” of the keypad  302 . The set cooking time is displayed on the display unit  224 . After the desired cooking temperature and time are set, a cooking operation is started in the baking mode by pushing the start button  304 . 
     FIG. 4  is a flow chart showing a method of controlling the microwave oven according to the embodiment of the present invention. As shown in  FIG. 4 , when a mode using the heaters is selected, as in a baking mode or a broiling mode at operation S 402 , a temperature of 220° C. is set as a basic temperature at operation S 404 . The control unit  202  determines whether a user changes a cooking temperature at operation S 406 . When the user changes the cooking temperature, the changed cooking temperature is displayed on the display unit  224  at operation S 408 . Thereafter, the user sets the changed cooking temperature by pushing numerical keys corresponding to the changed cooking temperature, as described in reference to  FIG. 3 . If a certain time period (e.g., 10 seconds) is elapsed after the cooking mode using the heaters is selected, the temperature of 220° C. as the basic temperature is decided as a final set temperature, considering that the user does not intend to change the cooking temperature. After setting of the cooking temperature is completed, the process is switched to the mode of setting a cooking time, in which a basic cooking time is set to a time of 10 seconds S 410 . In this operation, the control unit  202  also determines whether the user changes the cooking time at operation S 412 . When the user changes the cooking time, the changed cooking time is displayed on the display unit  224  at operation S 414 . 
   The control unit  202  determines whether the start button  304  is pushed at operation S 416 . If the start button  304  is pushed, a temperature of the cooking chamber  20  is increased to the set cooking temperature by heating of the upper heater  220  and the lower heaters  226  and  228  at operation S 418 . Thereafter, the control unit  202  determines whether a current temperature of the cooking chamber  20  reaches the set cooking temperature at operation S 420 . If the current temperature of the cooking chamber reaches the set cooking temperature, the current temperature remains at the set temperature at operation S 422 . If the current temperature of the cooking chamber  20  does not reach the set cooking temperature, the upper heater  220  and the lower heaters  226  and  228  are further operated to increase the temperature. When the cooking mode using the upper heater  220  and the lower heaters  226  and  228  is completed while the set temperature remains, the heating by the upper heater  220  and the lower heaters  226  and  228  is stopped and the cooking mode is concluded at operation S 424 . 
     FIG. 5  is a microwave oven according to the embodiment of the present invention. 
   As shown in  FIG. 5 , the microwave oven comprises a machine room  10  and a cooking chamber  20 . Several electrical devices, including a magnetron  11 , are installed in the machine room  10  so as to generate high-frequency electromagnetic waves. The housing of the microwave oven is partitioned into the machine room  10  and the cooking chamber  20  which defines a space to cook the food. High-frequency electromagnetic waves generated by the magnetron  210  are transmitted to the cooking chamber  20  to cook the food, which is placed in the cooking chamber  20 . 
   The cooking chamber  20  is defined by a rear wall  21 , a left sidewall  22  and a right sidewall  23 , an upper wall  24  and a bottom wall  25 , and is open at a front of the cooking chamber  20 . A door (not shown) is mounted to the open front so as to selectively open the cooking chamber  20 . A tray  216  and a tray motor  214  are installed at positions above and under the bottom wall  25  of the cooking chamber  20 , respectively. The food to be cooked is placed on the tray  216 . 
   An upper heater  220  is installed at a position adjacent to the upper wall  24  of the cooking chamber  20  and emits heat of a high temperature downwardly in the cooking chamber  20 . One or more middle heaters  226  and  228  are installed between the upper heater  220  and the tray  216  and emit heat of a high temperature upwardly and downwardly in the cooking chamber  20 . That is, the upper heater  220  is positioned at an upper portion in the cooking chamber  20 , and the one or more middle heaters  226  and  228  are positioned between the upper heater  220  and the tray  216 . Thus, heat is transmitted to upper and lower parts of the food placed between the upper heater  220  and the one or more middle heaters  226  and  228 . Further, heat is transmitted to the upper part of the food placed between the one or more middle heaters  226  and  228  and the tray  216 . 
   Each of the one or more middle heaters  226  or  228  is fixed to one rotating member of a pair of rotating members  226   a  and  228   a  and each of the pair of rotating members  226   a  and  228   a  is rotatably installed on the rear wall  21  of the cooking chamber  20 . As the rotating members  226   a  and  228   a  are rotated by a drive unit (not shown) which is installed outside the cooking chamber  20 , the one or more middle heaters  226  and  228  may be rotated between vertical closed positions, respectively, for which the one or more heaters  226  and  228  face the side walls and horizontal open positions, respectively, for which the one or more heaters  226  and  228  are directed to a center of the cooking chamber  20 . 
   A pair of upper supports  34  is provided between the upper heater  220  and the one or more middle heaters  226  and  228  so as to horizontally and inwardly protrude from the left and right sidewalls  22  and  23 , respectively. The pair of upper supports  34  supports a first food holding member  50  or a second food holding member  60  so as to slide in and out of the cooking chamber  20 . In the similar manner as the upper supports  34 , a pair of lower supports  35  is provided between the one or more middle heaters  226  and  228  and the tray  216  so as to horizontally and inwardly protrude from the left and right sidewalls  22  and  23 , respectively. The pair of lower supports  35  support the first food holding member  50  or the second food holding member  60  so as to allow the first food holding member  50  or the second food holding member  60  to slide in and out of the cooking chamber  20 . 
   The first and second food holding members  50  and  60  are removably seated on the upper and lower supports  34  and  35 , thus allowing one or more food items to be cooked in the cooking chamber  20 . A projection  36  is provided on a front portion of the left sidewall of the cooking chamber  20  at a position above one of the upper supports  34  and is spaced apart from the one upper support  34  by a predetermined interval. A vertical step  37  is provided at a position between the upper and lower supports  34  and  35  so as to be positioned at the front portion of the left sidewall  22 , and prevents the first food holding member  50  or second food holding member  60  from interfering with the one or more middle heaters  226  and  228  which are positioned between the upper and lower supports  34  and  35 . 
   As described above, a cooking apparatus having heaters with an input unit including numerical keys allocated with various cooking temperatures is provided. Accordingly, a user can easily perform a setting operation through a manipulation of the numerical keys. 
   Although a few preferred embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in this embodiment without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.