Patent Publication Number: US-2012031282-A1

Title: Cooking device

Description:
TECHNICAL FIELD 
     The present invention relates to a cooking device. 
     BACKGROUND ART 
     There is a conventional cooking device disclosed in JP 2007-327677 A (PTL 1). As shown in  FIG. 15 , the cooking device includes a casing  501 , a door  503  that is pivotably mounted on a front side of the casing  501 , and a cam mechanism  504  that operates with pivotal movement of the door  103 . 
     The cam mechanism  504  has a cam roller  531  and an arm  532  that is supported by the cam roller  531  so as to be movable in a to-and-fro direction with respect to the casing  501  (not shown in  FIG. 15 ). A front end part of the arm  532  is pivotably connected to the door  503 . On the other hand, a rear end part of the arm  532  is connected to the casing  501  through a coiled spring  533 . 
     As the door  503  fully closed is made to pivot in an opening direction in the cooking device having the above configuration, the arm  532  moves in a frontward direction with respect to the casing  501  so that a portion of the arm  532  is protruded forward from the casing  501 , as shown by two-dot chain lines in  FIG. 15 . As the door  503  fully opened is made to pivot in a closing direction, the arm  532  moves in a rearward direction with respect to the casing  501  so as to reach a state shown in solid lines in  FIG. 15 . 
     When the door  503  is fully opened in the conventional cooking device, as shown by the two-dot chain lines in  FIG. 15 , a space (a hatched part) that is generally shaped like a triangle in side view is produced between the protruded portion of the arm  532  and the door  503 . The space is comparatively small when the door  503  is fully opened and is comparatively large when the door  503  is partly opened. That is, the space gradually becomes smaller with transition of the door  503  from a partly opened state to a fully opened state. In case that a user accidentally puts his/her fingers into the space when the door  503  is partly opened and then fully opens the door  503 , accordingly, the fingers are nipped between the protruded portion of the arm  532  and the door  503 . 
     For the conventional cooking device, therefore, there is a risk that a user may be injured when opening or closing the door  503 . 
     It should be noted that  FIG. 15  is presented for convenience for clarifying problems with the conventional cooking device and does not completely coincide with a figure disclosed in JP 2007-327677 A. 
     CITATION LIST 
     Patent Literature 
     PTL1: JP 2007-327677 A 
     SUMMARY OF INVENTION 
     Technical Problem 
     An object of the invention is to provide a cooking device by which safety in opening and closure of a door can be improved. 
     Solution to Problem 
     A cooking device according to the present invention comprises: 
     a casing; 
     a heating compartment provided in the casing and having an opening on front face side thereof; 
     a door having one end pivotably mounted on the casing to open and close the opening of the heating compartment, 
     an arm having a front end part pivotably connected to the door, the arm being movable in a to-and-fro direction relative to the casing; and 
     a prevention mechanism preventing a finger or fingers of a user from being nipped when the door is opened and closed. 
     According to the cooking device having the above configuration, due to the provision of the prevention mechanism preventing a finger or fingers of a user from being nipped when the door is opened and closed, accidents can be prevented such as fracture of the fingers of the user that might be nipped between the door and the arm when the door is fully opened, so that safety in opening and closure of the door can be improved. 
     In one embodiment, when the door is fully opened, the prevention mechanism forms between the door and the arm a space of sufficient size allowing a finger or fingers of the user to be inserted in and withdrawn from the space. 
     According to the cooking device of the embodiment, when the door is fully opened, a space of sufficient size allowing a finger or fingers of the user to be inserted in and withdrawn from the space is formed between the door and the arm by the prevention mechanism. Thus the finger or fingers of the user can reliably be withdrawn, or removed, from the space even if the door is fully opened after the finger or fingers are inserted into the space between the door and the arm at a moment in partial opening of the door, for instance. 
     In one embodiment, the arm is movable by a cam mechanism. 
     According to the cooking device of the embodiment, because the arm is moved by the cam mechanism, an area in which the arm moves can be made small. Accordingly, a risk that the arm may be brought into contact with a hand of a user and/or the like can be reduced and safety of the user can be improved. 
     In one embodiment, the cam mechanism includes the arm, a cam roller rotatably mounted on a support part, and a spring member stretched between the casing and a rear end part of the arm. And, the arm includes a cam surface that is in slide contact with the cam roller, and a recess on a side of the arm that confronts the door such that the space of sufficient size allowing a finger or fingers of the user to be inserted in and withdrawn from the space is formed between the door and the arm by the recess when the door is fully opened. 
     According to the cooking device of the embodiment, because the space of sufficient size allowing a finger or fingers of the user to be inserted in and withdrawn from the space is formed between the door and the arm by the recess when the door is fully opened, safety of the user can reliably be improved with use of a simple structure. 
     In one embodiment, the prevention mechanism comprises the arm, which assumes a shape of a generally inverted letter U in side view once the door passes into a fully opened state from a fully closed state by 90° pivotal movement thereof, and the cooking device further comprises a spring member that biases the arm in a closing direction at beginning of opening of the door. 
     According to the cooking device of the embodiment, because the prevention mechanism comprises the arm that assumes the shape of a generally inverted letter U in side view once the door passes into the fully opened state from the fully closed state by 90° pivotal movement thereof, the space having the sufficient size allowing the finger(s) of the user to be inserted in and withdrawn from the space can reliably be formed between the door and the arm. 
     Besides, due to the provision of the spring member that biases the arm in the closing direction at beginning of opening of the door, the user can be prevented from being injured by the door being opened with great momentum when the door is opened. 
     In one embodiment, once the door passes into the fully opened state from the fully closed state by the 90° pivotal movement thereof, a distance between an end surface of the arm that confronts the door (referred to also as a door-side end surface) and a surface of the door that confronts the arm (referred to also as a arm-side surface) is not less than 10 mm and not more than 50 mm. 
     According to the cooking device of the embodiment, because once the door passes into the fully opened state from the fully closed state by the 90° pivotal movement thereof, there is a distance of not less than 10 mm between the door-side end surface of the arm and the arm-side surface of the door, a risk can be made extremely slight that fingers of the user could not be withdrawn from between the door and the arm with the fingers nipped between the door and the arm. 
     Besides, because once the door passes into the fully opened state from the fully closed state by the 90° pivotal movement thereof, there is a distance of not more than 50 mm between the door-side end surface of the arm and the arm-side surface of the door, the arm is prevented from being obstructive when an object to be cooked is put into or taken out of the heating compartment. 
     In one embodiment, the prevention mechanism comprises a prevention member that prevents the finger or fingers of the user from being nipped during transition of the door from the fully closed state to the fully opened state. 
     According to the cooking device of the embodiment, because the prevention mechanism comprises the prevention member that prevents the finger or fingers of the user from being nipped during transition of the door from the fully closed state to the fully opened state, any finger of the user is prevented from being nipped when the door is partly opened, for instance, and hence when the door is fully opened. 
     In one embodiment, the prevention member is a generally fan-shaped plate member mounted on an end part of the door on a side of the one end. 
     According to the cooking device of the embodiment, because the prevention member is a generally fan-shaped plate member mounted on an end part of the door on a side of the one end, safety of the user can reliably be improved with use of a simple structure. 
     In one embodiment, the prevention member is the arm, which assumes a shape of a generally letter V in side view once the door passes into the fully opened state from the fully closed state by 90° pivotal movement thereof. 
     According to the cooking device of the embodiment, because the arm, which is the prevention member, assumes the shape of a generally letter V in side view once the door passes into the fully opened state from the fully closed state by 90° pivotal movement thereof, it is possible to avoid formation of a space having a sufficient size allowing fingers of the user to be inserted in, during transition of the door from the fully closed state to the fully opened state. 
     Advantageous Effects of Invention 
     According to the cooking device of the present invention, due to the provision of the prevention mechanism preventing a finger or fingers of a user from being nipped when the door is opened and closed, those accidents that otherwise might occur during the opening and closing of the door are prevented, and safety of the user is thus improved. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a schematic front view of a cooking device in accordance with a first embodiment of the invention; 
         FIG. 2  is a schematic section of the cooking device in accordance with the first embodiment; 
         FIG. 3  is a schematic side view of a door fully closed and a cam mechanism in the first embodiment; 
         FIG. 4  is a schematic side view of the door fully opened and the cam mechanism in the first embodiment; 
         FIG. 5  is a schematic side view of the door partly opened and the cam mechanism in the first embodiment; 
         FIG. 6  is a schematic side view of a lower front part of a cooking device in accordance with a second embodiment of the invention; 
         FIG. 7  is a schematic side view of the lower front part of the cooking device in accordance with the second embodiment of the invention; 
         FIG. 8  is a schematic side view of the lower front part of the cooking device in accordance with the second embodiment of the invention; 
         FIG. 9  is a schematic side view of a lower front part of a cooking device in accordance with a third embodiment of the invention; 
         FIG. 10  is a schematic side view of the lower front part of the cooking device in accordance with the third embodiment of the invention; 
         FIG. 11  is a schematic side view of the lower front part of the cooking device in accordance with the third embodiment of the invention; 
         FIG. 12  is a schematic side view of a lower front part of a cooking device in accordance with a fourth embodiment of the invention; 
         FIG. 13  is a schematic side view of the lower front part of the cooking device in accordance with the fourth embodiment of the invention; 
         FIG. 14  is a schematic side view of the lower front part of the cooking device in accordance with the fourth embodiment of the invention; and 
         FIG. 15  is a schematic diagram for illustrating a conventional cooking device. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Hereinbelow, embodiments of the cooking device of the invention will be described in detail with reference to the drawings. 
     First Embodiment 
       FIG. 1  is a schematic illustration of a cooking device  100  in accordance with a first embodiment of the invention as seen looking from a front face side thereof. 
     The cooking device  100  includes a casing  101  that is shaped like a rectangular parallelepiped, a heating compartment  102  (see  FIG. 2 ) that is provided in the casing  101 , a door  103  that is pivotably mounted in front of the casing  101 , and a cam mechanism  104  (see  FIGS. 3 and 4 ) that operates with pivotal movement of the door  103 . 
     An opening  102   a  on front face side of the heating compartment  102  is opened and closed by the pivotal movement of the door  103 . A handle  110  is mounted on an upper part of the door  103 . Heat-resistant glass  111  is provided generally at a center part of the door  103 , so that a user can observe a state of inside of the heating compartment  102  through the heat-resistant glass  111 . Onto a rear face of the door  103 , packing  112  (not shown) made of heat-resistant resin is fixed so as to surround the heat-resistant glass  111 . 
     The packing is strongly pressed against a part surrounding the opening  102   a  of the heating compartment  102  when the door  103  is fully closed. Thus steam and/or the like in the heating compartment  102  are prevented from leaking out from between the door  103  and the part surrounding the opening  102   a  of the heating compartment  102 . 
     An operation panel  105  is provided on a right side of a front face of the casing  101 . The operation panel  105  has a liquid crystal display part  106 , a dial  107 , and a plurality of buttons  108 . A front face of a water supply tank  112  is exposed under the dial  107 . The water supply tank  112  is attachable to and detachable from the casing  101 . 
       FIG. 2  is a schematic section of the cooking device  100 , wherein reference numeral  114  denotes a drip tray, numeral  115  denotes a water level sensor, numeral  116  denotes a water supply pump, numeral  117  denotes a water supply pipe, numeral  118  denotes an upper heater, numeral  119  denotes an upper heater cover, numeral  120  denotes a tray, numeral  121  denotes a lower heater, numeral  122  denotes a thermal insulation plate, numeral  123  denotes an exhaust port, numeral  124  denotes an exhaust port cover, numeral  125  denotes an exhaust thermo-sensor, numeral  126  denotes an exhaust duct, numeral  126   a  denotes a cool-air introducing opening, numeral  127  denotes a cool-air path, numeral  128  denotes a diluted-exhaust port, and numeral  129  denotes a steam producing unit. Though not shown, a magnetron for producing microwave is also provided in the casing  101 . 
     The water supply pump  116  sucks water from the water supply tank  112  and delivers the water through the water supply pipe  117  to the steam producing unit  129 . The steam producing unit  129  is capable of producing steam by heating the water from the water supply pump  116  and supplying the steam into the heating chamber  102  and also capable of producing superheated steam by heating the steam and supplying the superheated steam into the heating chamber  102 . Herein, the above-mentioned superheated steam refers to steam heated to a superheated state with temperatures of higher than 100° C. 
     An object to be cooked  109  can be heated by the steam or the superheated steam from the steam producing unit  129  and/or can be heated by radiant heat from the upper heater  118  and the lower heater  121 . A top wall of the heating compartment  102  is under the upper heater  118  and a bottom wall of the heating compartment  102  is above the lower heater  121 , so that the upper heater  118  and the lower heater  121  are not exposed in the heating compartment  102 . 
       FIG. 3  is a schematic illustration of the door  103  fully closed and the cam mechanism  104  as seen looking from a lateral side.  FIG. 4  is a schematic illustration of the door  103  fully opened and the cam mechanism  104  as seen looking from the lateral side. 
     As shown in  FIGS. 3 and 4 , the cam mechanism  104  has a support base  130 , a cam roller  131 , an arm  132 , and a coiled spring  133 . Though only the cam mechanism  104  on the left side (which is a side opposite to the operation panel  105 ) of the heating compartment  102  is shown in  FIGS. 3 and 4 , a cam mechanism similar to or same as the cam mechanism  104  is provided on the right side (which is a side including the operation panel  105 ) of the heating compartment  102  as well. The support base  130  is an example of a support part, and the coiled spring  133  is an example of a spring member. 
     The support base  130  is fixed to a bottom part of the casing  101 . The support base  130  has an edge that extends in a horizontal direction, an edge that extends in a vertical direction, and an edge that extends so as to be inclined with respect to the horizontal direction, and is generally shaped like a right triangle in side view. The support base  130  has a hinge part  139  extending from the edge that extends in the vertical direction. A lower end part of the door  103  is pivotably mounted on the hinge part  139  through a door mounting shaft  140 . The door mounting shaft  140  is positioned below an arm connecting shaft  141  when the door  103  is fully closed and is positioned to rear of the arm connecting shaft  141  when the door  103  is fully opened. The arm connecting shaft  141  is provided inside the door  103  so as not to be exposed. 
     The cam roller  131  is rotatably mounted on the edge of the support base  130  that extends so as to be inclined with respect to the horizontal direction, and supports the arm  132  in such a manner that the arm  132  is movable in a to-and-fro direction. 
     A front end part of the arm  132  is connected to the door  103  through the arm connecting shaft  141 , so that the arm  132  is pivotable on the arm connecting shaft  141  with respect to the door  103 . The arm  132  has a cam surface  134  and a recess  135  on a face thereof confronting the cam roller  131  and has an engagement part  142  on a face thereof confronting the coiled spring  133 . 
     The cam surface  134  is in slide contact with the cam roller  131 . Sliding of the cam surface  134  on the cam roller  131  makes it possible for the arm  132  to follow the pivotal movement of the door  103 . 
     A section of the engagement part  142  that is taken along a horizontal plane is generally shaped like a letter U, so that the engagement part  142  nips and engages with the edge of the support base  130  when the door  103  is fully opened. Thus forward movement of the arm  132  relative to the casing  101  is restricted. When the door  103  is fully opened, clockwise moment about the door mounting shaft  140  is caused on the door  103  by gravity and counterclockwise moment about a contact point between the arm  132  and the cam roller  131  is caused on the arm  132  by a tension of the coiled spring  133 . The former moment is greater than the latter moment and thus the door  103  is kept open when a user takes his/her hand off the handle  110 . As the user makes the door  103  pivot from its full open position in a closing direction, the engagement part  142  is released from engagement and the arm  132  moves rearward by receiving a biasing force from the coiled spring  133  and a force from the user. 
     The recess  135  is provided on the side of the arm  132  that confronts the door  103  and is composed of a curved surface extending from a front end of the cam surface  134 . The recess  135  has such a shape as to form a space S, having a sufficient size allowing fingers of the user to be inserted therein and withdrawn therefrom, between the door  103  and the arm  132  when the door  103  is fully opened. More specifically, the shape of the arm  132  is designed so that a rectangle V shown by two-dot chain lines in  FIG. 4  has a height within a range of, e.g., from 15 to 20 mm and a width within a range of, e.g., from 20 to 30 mm. The rectangle V, which is a virtual figure, has a side coincident with an arm  132 -side edge of the door  103 , and two corners in contact with the recess  135  of the arm. 
     One end of the coiled spring  133  is hooked on a bend part  136 , generally shaped like a hook, of a rear end part of the support base  130 . The other end of the coiled spring  133  is inserted in a through hole  137  in a rear end part of the arm  132 . That is, the coiled spring  133  is stretched between the rear end part of the support base  130  and the rear end part of the arm  132 . The coiled spring  133  strongly biases the door  103  against the casing  101  through the arm  132 . Thus the packing is strongly pressed against the part surrounding the opening  102   a  of the heating compartment  102  when the door  103  is fully closed. 
     When the door  103  is made to pivot for transition thereof from a fully closed state in  FIG. 3  to a fully opened state in  FIG. 4 , in the cooking device  100  having the above configuration, the cam surface  134  slides on the cam roller  131  and the arm  132  moves forward so as to follow the pivotal movement of the door  103 . When the door  103  is fully opened, the recess  135  on the arm  132  forms the space S, having the sufficient size allowing a finger or fingers of the user to be inserted therein and withdrawn therefrom, between the door  103  and the arm  132 . 
     A space S′ having a sufficient size allowing fingers of the user to be inserted therein and withdrawn therefrom is formed between the door  103  and the arm  132  when the door  103  is partly opened, for instance, as shown in  FIG. 5 , and the door  103  and the arm  132  can be prevented from strongly nipping fingers of the user even if the door  103  is fully opened with the fingers of the user inserted in the space S′. 
     As a result, occurrence of accidents can be prevented such as fracture of a finger of the user which might otherwise be caused by the nip of the finger between the door  103  and the arm  132  when the door  103  is fully opened. That is, safety of the user can be improved in opening and closure of the door  103 . 
     The cam mechanism  104  has the coiled spring  133  stretched between the rear end part of the support base  130  and the rear end part of the arm  132  in the first embodiment, whereas the cam mechanism  104  may have a coiled spring stretched between the casing  101  and the rear end part of the arm  132 . 
     That is, in the invention, one end of the spring member may be mounted on the casing or may be mounted on another member fixed to the casing. 
     Though the hinge part  139  is provided on the support base  130  in the first embodiment, the hinge part  139  may be provided on the casing  101 . 
     Though the cam roller  131  is rotatably mounted on the support base  130  in the first embodiment, the cam roller  131  may rotatably be mounted on the casing  101 , for instance. 
     That is, the cam roller in the invention may rotatably be mounted on the casing or may rotatably be mounted on another member fixed to the casing. 
     The cooking device includes the cam mechanism  104  having the support base  130 , the cam roller  131 , the arm  132  and the coiled spring  133  in the first embodiment, whereas the cooking device may include a cam mechanism composed of members other than the support base  130 , the cam roller  131 , the arm  132  and the coiled spring  133 . 
     Second Embodiment 
       FIGS. 6 through 8  are schematic illustrations of lower front part of a cooking device in accordance with a second embodiment of the invention as seen looking from a lateral side thereof. In  FIGS. 6 through 8 , the same components as those of the first embodiment are provided with the same reference numerals as those in the first embodiment, and description thereof is omitted. In description below, the same components as those of the first embodiment are provided with the same reference numerals as those in the first embodiment, and description thereof will be omitted. 
     As shown in  FIG. 6 , the cooking device includes an arm  232  of which a front end part is pivotably connected to the door  103  and which is movable in a to-and-fro direction relative to the casing  101 , but has no cam mechanism. Though the arm  232  is provided on the left side (which is a side opposite to the operation panel  105 ) of the heating compartment  102 , an arm (not shown) similar to the arm  232  is provided also on the right side (which is a side including the operation panel  105 ) of the heating compartment  102 . The arm  232  is an example of the prevention mechanism. 
     A lower end part of the door  103  is mounted through a hinge  239  on lower front side of the casing  101 . In  FIGS. 6 through 8 , it is omitted to show a side part of the casing  101 . 
     A front end part of the arm  232  is connected to the door  103  through the arm connecting shaft  141 , so that the arm  232  is pivotable on the arm connecting shaft  141  with respect to the door  103 . One end of the coiled spring  133  is connected to a rear end part of the arm  232 . The other end of the coiled spring  133  is connected to a specified site on the casing  101 . 
     The coiled spring  133  biases the arm  232  in a closing direction at beginning of opening of the door  103 . More specifically, by the coiled spring  133 , the door  103  is biased toward the casing  101  when the door  103  is fully closed and a downward force is exerted on the arm connecting shaft  141  when the door  103  is fully opened. 
     A space S 1  having a sufficient size allowing a finger or fingers of a user to be inserted therein and withdrawn therefrom is formed between the door  103  and the arm  232  when the door  103  is partly opened as shown in  FIG. 7 , for instance, in middle of transition of the door  103  from a fully closed state in  FIG. 6  to a fully opened state in  FIG. 8  by 90° pivotal movement thereof. 
     Also, when the door  103  passes into the fully opened state in  FIG. 8 , a space S 2  having a sufficient size allowing a finger or fingers of the user to be inserted therein and withdrawn therefrom is formed between the door  103  and the arm  232 . At that time, the arm  232  has a shape of a generally inverted letter U, and a distance D between a door-side end surface of the arm  232  (which is a surface that confronts the door  103 ) and an arm-side surface of the door  103  (which is a surface that confronts the arm  232 ) is not less than 10 mm and not more than 50 mm. 
     In the cooking device having the above configuration, the space S 2  having the sufficient size allowing fingers of the user to be inserted therein and withdrawn therefrom is formed between the door  103  and the arm  232  when the door  103  is fully opened, and thus the fingers can reliably be withdrawn from between the door  103  and the arm  132  even if the door  103  is fully opened after the fingers of the user are inserted between the door  103  and the arm  232  when the door  103  is partly opened, for instance. 
     As a result, occurrence of accidents can be prevented such as fracture of the fingers of the user that might be nipped between the door  103  and the arm  132 . 
     The arm  232  assumes the shape of a generally inverted letter U in side view once the door  103  passes into the fully opened state in  FIG. 8  from the fully closed state in  FIG. 6  by the 90° pivotal movement thereof, and thus the space S 2  having the sufficient size allowing a finger or fingers of the user to be inserted therein and withdrawn therefrom can reliably be formed between the door  103  and the arm  232  when the door  103  is fully opened. 
     The distance D between the end surface of the arm  232  that faces the door  103  and the surface of the door  103  that faces the arm  232  is not less than 10 mm once the door  103  passes into the fully opened state in  FIG. 8  from the fully closed state in  FIG. 6  by the 90° pivotal movement thereof, and thus a risk can be made extremely slight that fingers of the user could not be withdrawn from between the door  103  and the arm  232  because being nipped between the door  103  and the arm  232 . 
     The distance D between the end surface of the arm  232  that faces the door  103  and the surface of the door  103  that faces the arm  232  is not more than 50 mm once the door  103  passes into the fully opened state in  FIG. 8  from the fully closed state in  FIG. 6  by the 90° pivotal movement thereof, and thus the arm  232  can be prevented from being obstructive when the object to be cooked  109  is put into or taken out of the heating compartment  102 . 
     Third Embodiment 
       FIGS. 9 through 11  are schematic illustrations of lower front part of a cooking device in accordance with a third embodiment of the invention as seen looking from a lateral side thereof. In  FIGS. 9 through 11 , the same components as those of the first embodiment are provided with the same reference numerals as those in the first embodiment, and description thereof is omitted. In  FIGS. 9 through 11 , some components are not shown for the sake of facilitation of understanding. In the description below, the same components as those of the first embodiment are provided with the same reference numerals as those in the first embodiment, and description thereof will be omitted. 
     The cooking device of this embodiment is different from the cooking device of the first embodiment only in that the former includes a plate member  350  that is generally shaped like a fan or sector in side view. Though the plate member  350  is provided on the left side (which is a side opposite to the operation panel  105 ) of the heating compartment  102 , a plate member (not shown) same as the plate member  350  is provided also on the right side (which is a side including the operation panel  105 ) of the heating compartment  102 . In  FIGS. 9 through 11 , a lateral side part of the casing  101  is not shown. The plate member  350  is an example of the prevention member. 
     The plate member  350  is mounted on a lower end part of one lateral end face of the door  103  so that at least a portion of the arm  132  cannot be seen from the lateral side when the door  103  is opened and closed. Thus a space having a sufficient size allowing a finger or fingers of a user to be inserted therein is not formed between the door  103  and the arm  132  during transition of the door  103  from a fully closed state to a fully opened state. 
     In the cooking device having the above configuration, the generally fan-shaped plate member  350  is mounted on the lower end part of the door  103  and thus fingers of a user are prevented from being inserted into between the door  103  and the arm  132  when the door  103  is opened and closed. 
     As a result, the fingers of the user are prevented from being nipped between the door  103  and the arm when the door  103  is fully opened, so that safety in opening and closure of the door  103  can reliably be improved with use of a simple structure. 
     The third embodiment has the configuration in which the plate member  350  is added to the cooking device  100  of the first embodiment, whereas the plate member  350  may be added to cooking devices other than the first embodiment. For instance, the plate member  350  may be added to the cooking device of JP 2007-327677 A. Injury to a user can be prevented by the cooking device of JP 2007-327677 A to which the plate member  350  is added, for instance, as done by the third embodiment. 
     Modifications similar to those described for the first embodiment may be made to the third embodiment. 
     Fourth Embodiment 
       FIGS. 12 through 14  are schematic illustrations of a lower front part of a cooking device in accordance with a fourth embodiment of the invention as seen looking from a lateral side thereof. In  FIGS. 12 through 14 , the same components as those of the first embodiment are provided with the same reference numerals as those in the first embodiment, and description thereof is omitted. In the description below, the same components as those of the first embodiment are provided with the same reference numerals as those in the first embodiment, and description thereof will be omitted. 
     As shown in  FIG. 12 , the cooking device includes an arm  432  of which front end part is pivotably connected to the door  103  and which is movable in a to-and-fro direction relative to the casing  101 , but has no cam mechanism. Though the arm  432  is provided on the left side (which is a side opposite to the operation panel  105 ) of the heating compartment  102 , an arm (not shown) similar to the arm  432  is provided also on the right side (which is a side including the operation panel  105 ) of the heating compartment  102  as well. The arm  432  is an example of the prevention member. 
     A lower end part of the door  103  is mounted through the hinge  239  on a lower front side of the casing  101 . In  FIGS. 12 through 14 , a lateral side part of the casing  101  is not shown. 
     The front end part of the arm  432  is connected to the door  103  through an arm connecting shaft  241  provided on one side end face of the door  103 , so that the arm  432  is pivotable on the arm connecting shaft  441  with respect to the door  103 . One end of the coiled spring  133  is fitted to a rear end part of the arm  432 . The other end of the coiled spring  133  is fitted to a specified site of the casing  101 . 
     The coiled spring  133  biases the arm  432  in a closing direction at beginning of opening of the door  103 . By the coiled spring  133 , more specifically, the door  103  is biased toward the casing  101  when the door  103  is fully closed and a downward force is exerted on the arm connecting shaft  441  when the door  103  is fully opened. 
     A space having a sufficient size allowing fingers of a user to be inserted therein and withdrawn therefrom is not formed between the door  103  and the arm  432  when the door  103  is partly opened as shown in  FIG. 13 , for instance, in middle of transition of the door  103  from a fully closed state in  FIG. 12  to a fully opened state in  FIG. 14  by 90° pivotal movement thereof. 
     A space having a sufficient size allowing the fingers of the user to be inserted therein and withdrawn therefrom is not formed between the door  103  and the arm  432  when the door  103  is in the fully opened state in  FIG. 14 . At that time, the arm  432  is generally in shape of a letter V in side view. 
     In the cooking device having the above configuration, which includes the arm  432 , the space having the sufficient size allowing a finger or fingers of a user to be inserted therein and withdrawn therefrom is not formed between the door  103  and the arm  432  during the transition of the door  103  from the fully closed state in  FIG. 12  to the fully opened state in  FIG. 14  by the 90° pivotal movement thereof. 
     As a result, the fingers of the user are prevented from being nipped between the door  103  and the arm when the door  103  is fully opened, so that safety in opening and closure of the door  103  can reliably be improved. 
     That is, the cooking device of the fourth embodiment attains functional effects similar to those of the third embodiment. In the cooking device of the fourth embodiment, in addition, no cam mechanism is provided and thus number of components thereof and cost for manufacture thereof can be reduced in comparison with the third embodiment. 
     Though the steam producing unit  129  that has a function of producing superheated steam is mounted in the cooking device  100  in the first through fourth embodiments, a steam producing device that merely produces steam and that has no function of producing superheated steam may be mounted in the cooking device  100 . 
     The invention may be applied not only to microwave ovens in which superheated steam is used but also to cooking devices such as cooking ovens, cooking ranges, microwave ovens, and IH cooking heaters in which superheated steam is not used and cooking devices such as cooking ovens, cooking ranges, and IH cooking heaters in which superheated steam is used, for instance. 
     With the cooking devices of the invention, healthy cooking can be performed by use of superheated steam or saturated steam in cooking heaters (including those using IH heaters, electric cooking stoves such as electric heaters, or gas cooking stoves), microwave ovens and the like. In the cooking devices of the invention, for instance, superheated steam or saturated steam having a temperature not lower than 100° C. is supplied onto surfaces of food, the superheated steam or saturated steam deposited onto the surfaces of the food condenses and gives the food a great quantity of latent heat of condensation, and therefore heat can efficiently be transmitted to the food. The condensate water is deposited on the surfaces of the food, and salt content, oil content and the like of the food drop with the condensate water, so that salt content, oil content and the like of the food can be reduced. Furthermore, the heating compartment is filled with the superheated steam or saturated steam so as to be in a state poor in oxygen, and thus cooking by which oxidation of the food is suppressed can be performed. 
     The invention is not limited to the first through fourth embodiments and can be embodied with modification in various ways within the scope of the invention. For instance, matters described for the first through fourth embodiments may be appropriately combined as needed and such combination may be implemented as an embodiment of the invention. 
     The invention can be applied not only to cooking devices having doors of vertical opening type as in the first through fourth embodiments but also to cooking devices having doors of horizontal opening type. 
     REFERENCE SIGNS LIST 
       100  cooking device 
       101  casing 
       102  heating compartment 
       103  door 
       104  cam mechanism 
       130  support base 
       131  cam roller 
       132 ,  232 ,  432  arm 
       133  coiled spring 
       134  cam surface 
       135  recess 
       350  plate member 
     S, S′, S 1 , S 2  space