Heating cooker

Abstract

A heating cooker (10) comprises: a heating chamber (28) that accommodates food inside a body (11); a plurality of tube heaters (31) that pass through the heating chamber (28) and that irradiate the heating chamber (28); at least two pieces of protective glass (33) that protect the tube heaters (31); and reflection plates (34) that reflect radiant heat (T31) from the tube heaters (31). The heating cooker (10) comprises, in the given order from an outer side of the heating chamber (28), the reflection plates (34), the tube heaters (31), and the protective glass (33).

Description

heating cooker

[0001] The present invention relates to a cooking device.

[0002] Literature describing the configuration of the heater area of ​​a cooking appliance includes, for example, Patent Documents 1 to 5. Patent Document 1 describes a configuration in which a perforated metal is provided on a portion of the wall of a heating chamber, and a spacer, a transparent plate (glass), a heat source (halogen lamp), and a reflector are arranged on the perforated metal. Patent Document 2 describes a configuration in which chokes are arranged around the heater to suppress radio wave leakage from the heater to the outside of the cooking appliance. Patent Document 3 describes a configuration in which a squeezed portion is provided on the wall of the heating chamber, and at least one turn of a coiled heater wire is contained within the squeezed portion. Patent Document 4 describes a configuration in which a heater with a heat-activated deodorizing catalyst coated on its surface is arranged above the perforated metal, and air is passed from the inside to the outside of the cooking appliance through the perforated metal by an ascending air current, thereby deodorizing the cooking appliance. Patent Document 5 describes a configuration in which a protective plate is arranged to cover the underside of a heater stored in a heater storage chamber, and the protective plate catches any objects that fall into the heater storage chamber.

[0003] Japanese Patent Laid-Open No. 4-295522 Japanese Patent Laid-Open No. 59-150221 Japanese Utility Model Publication No. 5-30315 Japanese Patent Laid-Open No. 5-157252 Japanese Patent Laid-Open No. 2010-112578

[0004] In all of the conventional cooking devices described in Patent Documents 1 to 5, it is desirable to improve the ease of cleaning the heating chamber while ensuring high heating power.

[0005] The present invention has been made to solve the above-mentioned problems, and a main object of the present invention is to provide a cooking device that ensures high heating power while improving the ease of cleaning the heating chamber.

[0006] In order to achieve the above object, the present invention provides a cooking appliance comprising a heating chamber for storing food inside a main body, a plurality of tube heaters that penetrate the heating chamber and irradiate the heating chamber, two or more protective glasses for protecting each of the tube heaters, and a reflector for reflecting radiant heat from the tube heaters, the reflector, the tube heaters, and the protective glasses being arranged in this order from the outside of the heating chamber. Other means will be described later.

[0007] According to the present invention, it is possible to improve the cleaning ability of the heating chamber while ensuring high heating power.

[0008] 1 is a perspective view of the appearance of a cooking device according to an embodiment; FIG. 1 is a cross-sectional view taken along the X1-X1 line in FIG. 1; FIG. 1 is a cross-sectional view of a heating unit seen from the side; FIG. 1 is a cross-sectional view of a heating unit according to a modified example seen from the side; FIG. 1 is a cross-sectional view of an upper part of a heating chamber of a cooking device seen from the side; FIG. 1 is a cross-sectional view of an upper part of a heating chamber of a cooking device seen from the top; FIG. 1 is a perspective view of a choke; FIG. 1 is a development view of a choke; FIG. 1 is a rear view of a choke; FIG. 1 is a bottom view of a choke; FIG. 1 is a side view showing a state in which a tube heater is held by the choke; FIG. 1 is a schematic explanatory view of an example of the arrangement of a heating unit in a cooking device according to a first comparative example; FIG. 1 is a schematic explanatory view of an example of the arrangement of a heating unit according to another modified example; FIG. 1 is a cross-sectional view of a heating unit according to another modified example seen from the side; FIG. 1 is an explanatory view of a problem in a cooking device according to a second comparative example in which a planar heater is used in the heating unit; FIG. 1 is a cross-sectional view of a heating unit of a cooking device according to a modified example using a planar heater seen from the side; FIG. 1 is a three-dimensional assembly view of mounting a heating unit according to a reference example of the present invention; FIG. 1 is a view showing an example of screw fastening; FIG. 1 is a view showing an example of adhesive fastening; FIG. 1 is a view showing an example of inset adhesive fastening; FIG. 1 is a view showing an example of screw fastening with punched metal installed. FIG. 1 is a diagram showing an example of adhesive fixing with punching metal installed; FIG. 2 is a diagram showing an example of fit-in adhesive fixing with punching metal installed; FIG. 3 is a diagram showing an example of screw fastening with positioning parts installed; FIG. 4 is a diagram showing an example of adhesive fixing with positioning parts installed; FIG. 5 is a diagram showing an example of fit-in adhesive fixing with positioning parts installed; FIG. 6 is a diagram showing an example of screw fastening with punching metal and positioning parts installed; FIG. 7 is a diagram showing an example of adhesive fixing with punching metal and positioning parts installed; FIG. 8 is a diagram showing positioning by a recess in a wall surface.

[0009] Hereinafter, an embodiment of the present invention (hereinafter referred to as "the present embodiment") will be described in detail with reference to the drawings. Note that each drawing is merely a schematic illustration to allow a sufficient understanding of the present invention. Therefore, the present invention is not limited to the illustrated examples. Furthermore, in each drawing, common or similar components are designated by the same reference numerals, and redundant explanations thereof will be omitted.

[0010] The present embodiment is also intended to provide a cooking device that can solve the following problems.

[0011] <(1) First Problem> The above-mentioned Patent Document 1 has the following problems. (1a) Patent Document 1 has a problem in that a transparent plate (glass) is placed between the heat source and the perforated metal, and radiant heat that is reflected by the non-opening parts of the perforated metal and then reflected by the reflector repeatedly passes through the transparent plate, thereby reducing heating performance. In other words, Patent Document 1 has a problem in that the radiant heat repeatedly passes through the transparent plate, causing the amount of heat that should be used to heat food to be absorbed and attenuated by the transparent plate, making it impossible to effectively use the heat.

[0012] <(2) Second Problem> The above-mentioned Patent Documents 2 and 3 have the following problems. (2a) Patent Document 2 has the problem that the choke is easily heated because it is configured on the heating chamber wall surface inside the heating chamber, and the heating chamber wall is close to the heater, so the choke is easily thermally deformed, changing the choke depth and reducing the electromagnetic wave shielding effect. (2b) Furthermore, Patent Document 3 has the problem that a drawn portion (positioning portion) is configured on the heating chamber wall, and the relative position of the heater and the drawn portion can be defined, but the heating chamber wall is close to the heater, so the drawn portion is easily deformed, causing a shift in the relative position of the heater and the choke, reducing the electromagnetic wave shielding effect.

[0013] <(3) Third Problem> The above-mentioned Patent Documents 1 and 4 have the following problems. (3a) Patent Document 1 has the problem that only radiant heat that passes through the openings (holes) of the perforated metal contributes to heating food, resulting in poor heating performance. (3b) Furthermore, Patent Document 4 has the problem that dirt (part of the food) passes through the holes of the perforated metal and penetrates into the heater side, making it impossible to clean and remove the infiltrated dirt. In this regard, dirt that adheres to the cooking chamber side of the perforated metal can be removed by wiping it off, but dirt that adheres to the heater side of the perforated metal cannot be removed because it is impossible to reach in and wipe it off.

[0014] <Fourth Problem> The above-mentioned Patent Document 5 has the following problems: (4a) Patent Document 5 has a problem that an air layer formed between the planar heater serving as a heat source and the protective plate may reduce heating performance.

[0015] <Configuration of Cooker> Fig. 1 is an external perspective view of a cooker 10 according to this embodiment, showing the configuration of a main body 11 of the cooker 10 as viewed from the front side. In Fig. 1, the main body 11 of the cooker 10 places food to be heated in a heating chamber 28, and cooks the food using microwaves, heat from a heater, or even superheated steam.

[0016] The outer frame 18 is a cabinet that covers the top and left and right sides of the main body 11 of the cooking appliance 10. The door 12 opens and closes to put food in and take it out of the heating chamber 28. Closing the door 12 seals the heating chamber 28, preventing leakage of microwaves used to heat food and sealing in the heat of the heater and superheated steam, enabling efficient heating.

[0017] Handle 19 is attached to door 12 and is shaped to be easy to grip, making it easy to open and close door 12. Glass window 13 is attached to door 12 so that the state of food being cooked can be checked, and is made of glass that can withstand high temperatures generated by heaters, etc.

[0018] The input unit 15 is provided on the operation panel 14 on the lower front side of the door 12, and is composed of a display unit 16 that displays the contents input from the operation unit 17 and the progress of cooking, and an operation unit 17 for inputting the heating unit such as microwave heating or heater heating, the heating time, etc., and the heating temperature.

[0019] Figure 2 is a cross-sectional view taken along the line X1-X1 in Figure 1. In Figure 2, machine chamber 20 is provided in the space between heating chamber bottom surface 28a and bottom plate 21 of main body 11, and on bottom plate 21 are mounted magnetron 45 for heating food, a control board on which waveguide 47 connected to magnetron 45 and the like are mounted, various other components, and a fan device for cooling these various components.

[0020] Heating chamber bottom surface 28a has a recess in the approximate center, within which rotating antenna 26 is installed, and microwave energy radiated from magnetron 45 flows into the underside of rotating antenna 26 through waveguide 47 and opening 47a through which output shaft 46a of rotating antenna 26 passes, where it is diffused by rotating antenna 26 and radiated into heating chamber 28. Output shaft 46a of rotating antenna 26 is connected to rotating antenna driver 46.

[0021] A heating unit 30 made up of a heater is attached to the back side of the heating chamber ceiling 28c of the heating chamber 28.

[0022] The bottom surface 28a of the heating chamber 28 is provided with a plurality of weight sensors SN1, for example, a left weight sensor SN1a and a right weight sensor (not shown) on the left and right sides of the front, and a rear weight sensor SN1b is provided in the center of the rear, on which the table plate 24 is placed.

[0023] An infrared sensor SN2 for detecting the surface temperature of food materials and a temperature sensor SN3 for detecting the temperature inside the heating chamber 28 are provided on the left rear side of the heating chamber top surface 28c of the heating chamber 28.

[0024] The table plate 24 is used to place food on, and is made of a heat-resistant material that can be used for both heater heating and microwave heating, and is also highly permeable to microwaves.

[0025] <Configuration of Heating Unit> FIG. 3 is a cross-sectional view of the heating unit 30 as viewed from the side. As shown in FIG. 3, the cooking appliance 10 includes multiple heating units 30 above the top wall 29 of the heating chamber 28. In the example shown in FIG. 3, each heating unit 30 includes a tube heater 31 that irradiates the heating chamber 28 as a heat source, a protective glass 33 that protects the tube heater 31, a reflector 34 that reflects radiant heat T31 from the tube heater 31, and a metal plate 35 having multiple through holes 35h. Each heating unit 30 is arranged in the following order from the inside to the outside of the heating chamber 28: the protective glass 33, the metal plate 35, the tube heater 31, and the reflector 34. In other words, the cooking appliance 10 includes multiple heating units 30 arranged in the following order from the outside to the inside of the heating chamber 28: the reflector 34, the tube heater 31, the metal plate 35, and the protective glass 33. The tube heater 31 is sometimes referred to as a glass tube heater.

[0026] The protective glass 33 is made of a heat-resistant, transparent glass material and has a rectangular, flat plate shape. The metal plate 35 is made of perforated metal, metal mesh, or the like. The metal plate 35 shields microwaves during microwave heating and suppresses electromagnetic wave leakage outside the oven. The metal plate 35 is positioned facing the upper surface of the protective glass 33. The metal plate 35 is positioned so as to be in contact (close contact) with or adjacent to the upper surface of the protective glass 33. The edge of the metal plate 35 is bent so as to rest on the bent portion of the top wall 29. The metal plate 35 has multiple through holes 35h formed in a direction perpendicular to the plate surface of the metal plate 35. Radiant heat T31 irradiated from the tube heater 31 and radiant heat T31 reflected by the reflector 34 passes through the top wall 29 via the through holes 35h and the protective glass 33, reaches the heating chamber 28, and heats the food stored in the heating chamber 28.

[0027] The reflector 34 is disposed facing the top wall 29. The protective glass 33, the metal plate 35, and the tube heaters 31 are disposed between the top wall 29 and the reflector 34. The reflector 34 has a bent or curved shape so as to surround the upper surface of each tube heater 31. The reflector 34 is fixed to the top wall 29 at any plurality of locations with screws 36. However, the reflector 34 may be fixed to the top wall 29 with adhesive instead of the screws 36. The reflector 34 is disposed so as to contact (closely contact) or be close to the upper surface of the middle portion 29a of the top wall 29. In the example shown in FIG. 3 , the reflector 34 is disposed so as to contact (closely contact) the middle portion 29a and is fixed with the screws 36. This allows the heating unit 30 to efficiently transfer heat from the reflector 34 to the heating chamber 28 via thermal conduction T11. The intermediate portion 29 a is a portion of the top wall 29 between the pipe heaters 31 .

[0028] The top wall 29 has the aforementioned intermediate portion 29a and folded portion 29b. The folded portion 29b is the portion on which the protective glass 33 is placed and has a folded shape. The top wall 29 has protrusions 29p near the end of the folded portion, and the protrusions 29p are fitted into through-holes 35h in the metal plate 35 above the protective glass 33 to secure the metal plate 35. The protrusions 29p of the top wall 29 and the through-holes 35h in the metal plate 35 are preferably fitted at intervals of approximately 20 mm or less along the four edges of the protective glass 33 to provide electromagnetic wave shielding. Furthermore, the surface of the top wall 29 facing the heating chamber 28 is painted with a high-radiation paint. This allows heat from the top wall 29 to be efficiently transferred to the heating chamber 28.

[0029] The cooking device 10 including such a heating unit 30 can be easily cleaned because the underside of the metal plate 35 (punched metal, metal mesh, etc.) is covered with the protective glass 33.

[0030] Furthermore, the cooking device 10 is configured such that multiple protective glass panels 33 are arranged separately on the top wall 29 of the heating chamber 28, and a reflector 34 is arranged so as to contact (closely adhere) or be close to an intermediate portion 29a of the top wall 29. This allows the cooking device 10 to efficiently transfer heat from the reflector 34 to the heating chamber 28 via the intermediate portion 29a. This cooking device 10 can effectively use the heat from the reflector 34 to cook food, thereby improving heating performance. Furthermore, by arranging the multiple protective glass panels 33 separately, the volume of the protective glass panels, and therefore their heat capacity, can be reduced, and the amount of heat absorbed by the protective glass panels 33 is reduced, improving heating performance.

[0031] The cooking appliance 10 is configured with multiple heating units 30, which are arranged in the following order from the outside to the inside of the heating chamber 28: a reflector 34, a tube heater 31 (heat source), a metal plate 35 (e.g., punched metal or metal mesh), and a protective glass 33. If the positions of the metal plate 35 and the protective glass 33 were reversed, i.e., if the protective glass 33 were provided between the tube heater 31 (heat source) and the metal plate 35, the re-reflected wave (radiant heat T31) reflected by a non-opening (a portion other than the through-hole 35h) in the metal plate 35 and then reflected by the reflector 34 would repeatedly pass through the protective glass 33. Therefore, with this configuration, as in Patent Document 1, for example, the amount of heat required to heat the food would be absorbed and attenuated by the protective glass 33, resulting in ineffective use of the heat and reduced heating performance. In contrast, in the cooking appliance 10, the protective glass 33 is not provided between the tube heater 31 (heat source) and the metal plate 35 (perforated metal, metal mesh, or the like), but is provided below the metal plate 35. This cooking appliance 10 can prevent the re-reflected wave (radiant heat T31) that is reflected by non-openings (areas other than the through-holes 35h) of the metal plate 35 and then reflected by the reflector 34 from repeatedly passing through the protective glass 33. Therefore, the cooking appliance 10 can efficiently send the re-reflected wave (radiant heat T31) to the heating chamber 28, thereby improving heating performance.

[0032] Cooking appliance 10 is also configured such that top wall 29 of heating chamber 28 is folded back to contact protective glass 33. Cooking appliance 10 of this type can be cleaned without causing any problems even if the edge of top wall 29 hits the user's fingers.

[0033] Furthermore, in the cooking appliance 10, the metal plate 35 is fixed to the top wall 29 by fitting the protrusion 29p of the top wall 29 into the through-hole 35h of the metal plate 35 above the protective glass 33. In the cooking appliance 10, the fitting portion between the protrusion 29p of the top wall 29 and the through-hole 35h of the metal plate 35 can be positioned in a location hidden from the heating chamber 28. In such a cooking appliance 10, the fitting portion does not get in the way of cleaning. Therefore, the cooking appliance 10 makes it easy to clean the heating chamber 28.

[0034] Furthermore, the cooking appliance 10 is arranged so that the metal plate 35 is in contact (close contact) with or close to the protective glass 33. Therefore, the cooking appliance 10 can efficiently transfer heat from the metal plate 35 to the heating chamber 28 via the protective glass 33, thereby improving heating performance.

[0035] Due to these factors, the cooking appliance 10 can improve the cleaning properties of the heating chamber 28 while ensuring high heating power.

[0036] <Configuration of heating section according to modified example> The heating section 30 shown in Fig. 3 can be modified to form a heating section 30A shown in Fig. 4. Fig. 4 is a cross-sectional view of the heating section 30A according to the modified example, seen from the side.

[0037] As shown in Fig. 4, the heating unit 30A according to the modified example differs from the heating unit 30 shown in Fig. 3 in that the reflecting plate 34 is composed of a reflecting surface portion 34a and a strengthening portion 34b. The reflecting surface portion 34a is a member that reflects radiant heat T31 from the tube heater 31. The strengthening portion 34b is a member that holds the reflecting surface portion 34a.

[0038] The reflecting surface portion 34a is made of a metal material with high reflectivity, such as an aluminum alloy. The strength portion 34b is made of a metal material with higher strength than the reflecting surface portion 34a. The reflecting surface portion 34a has high reflectivity and excellent plasticity, but is easily deformed. Therefore, the heating unit 30A according to the modified example is configured so that the strength portion 34b holds the reflecting surface portion 34a.

[0039] In the example shown in FIG. 4, the reflecting surface portion 34a is attached to the reinforcing portion 34b by hook-shaped fixing portions 34ba, 34bb, and 34bc provided on the reflecting surface portion 34a.

[0040] Such a heating section 30A allows the reflecting surface section 34a to be easily formed into any desired shape, and the reinforcing section 34b can hold the reflecting surface section 34a so that it does not deform.

[0041] 4, the cooking appliance 10 is provided with a heat insulating material 38 above the reflecting plate 34. This allows the cooking appliance 10 to reduce the amount of heat transferred from the reflecting plate 34 side to the housing outer frame 37 side and increase the amount of heat transferred from the reflecting plate 34 side to the heating chamber 28 side. This allows the cooking appliance 10 to improve its heating performance.

[0042] <Modifications of the support structure for the tube heater and the electromagnetic wave shielding structure> Cooking appliance 10 may be configured to include a choke 40 (Fig. 5) for shielding electromagnetic waves according to another modification, instead of metal plate 35 (Figs. 3 and 4). Fig. 5 is a cross-sectional view of the upper part of the heating chamber of the cooking appliance as seen from the side, and Fig. 6 is a cross-sectional view of the upper part of the heating chamber of the cooking appliance as seen from the top.

[0043] As shown in Figures 5 and 6, the cooking device 10 is configured to include a heating chamber 28 for storing food, a tube heater 31 for heating the inside of the heating chamber 28, and a choke 40 for blocking electromagnetic waves.

[0044] The heating chamber 28 has a top wall 29 that forms the top surface (upper surface). This top wall 29 is configured to include a plate portion 291 that extends horizontally, a plate portion 293 that extends horizontally at a position higher than plate portion 291, and a plate portion 292 that connects plate portions 291 and 293 and extends vertically (up and down). This forms a step between plate portions 291 and 293. The lower side in the figure, partitioned by plate portions 291 to 293, is the inside of the heating chamber 28, and the upper side in the figure is the outside of the heating chamber 28.

[0045] The tube heater 31 has a heating element disposed within a cylindrical tube portion 31a. An insulating portion 31b is provided at the end of the tube heater 31, and an electric wire (lead wire) 31c extends from the insulating portion 31b. For example, the tube heater 31 may be a quartz tube heater, a halogen heater, or a carbon heater. While the present embodiment describes a tube heater 31 extending in the left-right direction, the tube heater may also extend in the front-rear direction.

[0046] A through-hole 28f through which the tube heater 31 passes in the left-right direction is formed in the plate portion 292. This through-hole 28f is circular and formed larger than the outer diameter of the tube heater 31, so that a gap (space) 29s is formed between the tube heater 31 and the through-hole 28f. In other words, the tube heater 31 does not contact the edge of the through-hole 28f.

[0047] Choke 40 is formed by bending and cutting a steel plate, and is installed on plate portion 291 located outside heating chamber 28. In other words, choke 40 is fixed to the surface of the heating chamber wall (the upper surface of plate portion 291) that is parallel to tube heater 31. Note that the electromagnetic waves that pass through conductor 31d of tube heater 31 and exit heating chamber 28 and the electromagnetic waves reflected within choke 40 cancel each other out, thereby preventing electromagnetic waves from leaking outside heating chamber 28.

[0048] The tube heater 31 passes through the choke 40, and the insulating portion 31b of the tube heater 31 is fitted into the hole 41h for support. Furthermore, since the electric wire 31c extends from the inside of the insulating portion 31b, the electric wire 31c and the hole 41h do not come into contact with each other.

[0049] 7A is a perspective view of the chalk, FIG. 7B is a development view of the chalk, FIG. 7C is a rear view of the chalk, and FIG. 7D is a bottom view of the chalk. As shown in FIG. 7A, the chalk 40 is configured by combining a plate member 41 provided on the outside and a plate member 42 provided on the inside.

[0050] The plate member 41 has an upper surface portion 41a located on the upper surface, a side surface portion 41b extending downward from one opposing edge portion of the upper surface portion 41a, a bottom surface portion 41c extending outward from the lower edge portion of the side surface portion 41b, and a side surface portion 41d (one side of the choke) extending downward from one of the other opposing edges of the upper surface portion 41a.

[0051] As shown in FIG. 7B , the plate members 41 and 42 are each formed from a single plate material. In FIG. 7B , the folding lines along which the plate members 41 and 42 are folded are indicated by dashed lines. The plate member 41 has side portions 41b, 41b located on one side of the top portion 41a, and a bottom portion 41c located on the opposite side of the side portion 41b from the top portion 41a. The plate member 41 also has a side portion 41d located on the other side of the top portion 41a. The top portion 41a and the side portion 41d are formed to have approximately the same width. The bottom portion 41c has a screw insertion hole 41e through which a screw 43 (see FIG. 6 ) is inserted. The side portion 41d has a substantially semicircular hole 41h extending therethrough. As described above, this hole 41h holds the tube heater 31.

[0052] The plate member 42 is disposed inside the plate member 41 and has a top surface 42a, side surfaces 42b, 42b, and bottom surfaces 42c, 42c. The top surface 42a is narrower than the top surface 41a and is located in the center. The side surfaces 42b, 42b are located on one side opposite the top surface 42a. The side surface 42b is narrower than the side surface 41b. The bottom surface 42c is located on the opposite side of the side surface 42b from the top surface 42a. The bottom surface 42c is wider than the bottom surface 41c. Furthermore, a screw insertion hole 42d is formed in the bottom surface 42c, through which a screw 43 (see FIG. 6) is inserted.

[0053] In the plate member 41, a mountain fold is formed between the top surface portion 41a and the side surface portion 41b, and between the top surface portion 41a and the side surface portion 41d. In the plate member 41, a valley fold is formed between the side surface portion 41b and the bottom surface portion 41c. In the plate member 42, a mountain fold is formed between the top surface portion 42a and the side surface portion 42b, and a valley fold is formed between the side surface portion 42b and the bottom surface portion 42c.

[0054] 7C, when viewed from the side opposite side portion 41d, gate-shaped spaces 41s are formed between top surface portion 41a and top surface portion 42a and between side surface portion 41b and side surface portion 42b. Bottom surface portion 41c is superimposed on the top surface of bottom surface portion 42c. Hole 41h is formed so as to be located within space 42s surrounded by top surface portion 42a and side surface portions 42b, 42b.

[0055] As shown in FIG. 7D , the choke 40 is assembled by combining the plate members 41 and 42 such that the screw insertion hole 42d in the bottom surface 42c and the screw insertion hole 41e (see FIG. 7B ) in the bottom surface 41c are aligned vertically. The length of the plate member 42 in the short-side direction (the vertical direction in the figure) is shorter than the length of the plate member 41 in the short-side direction (the vertical direction in the figure). The bottom surface 42c of the plate member 42 is disposed in surface contact with the upper surface of the plate portion 291 (see FIG. 5 ). Screws 43 (see FIG. 6 ) are inserted from above through the screw insertion holes 41e and 42d and screwed into the plate portion 291, thereby securing the choke 40 to the plate portion 291. Note that the method of securing the choke 40 to the plate portion 291 is not limited to screw securing, and other securing methods, such as welding, may also be used.

[0056] FIG. 8 is a side view showing the state in which the tube heater is held by the choke. As shown in FIG. 8, a hole 41h is formed in the side surface 41d of the plate member 41. This hole 41h is approximately semicircular, with the straight portion facing upward and the curved portion facing downward. The insulating portion 31b of the tube heater 31 is fitted into the hole 41h. The electric wire 31c is drawn out from inside the insulating portion 31b. By making the hole 41h approximately semicircular, the tube heater 31 does not rotate around the axial direction of the tube heater 31 within the hole 41h. This prevents the relative position of the tube heater 31 and the choke 40 from changing. Note that the shape of the hole 41h is not limited to approximately semicircular. It may be any other shape, such as a square, triangle, polygon, or ellipse, as long as the tube heater 31 does not rotate within the hole 41h.

[0057] 5 and 6, when choke 40 is fixed to plate portion 291, top surface portion 41a and side surfaces 41b, 41b are in approximate contact with plate portion 292. Note that "approximate contact" may mean either contact or no contact, but when no contact is present, it means that the gap between top surface portion 41a and side surfaces 41b and plate portion 292 is small enough (for example, 1 mm) that electromagnetic waves do not leak out from the gap.

[0058] Furthermore, the tube heater 31 passing through the through-hole 28f is disposed in a space 42s (see FIG. 7C) surrounded by the upper surface 42a and the side surfaces 42b, 42b of the choke 40. Furthermore, the tube heater 31 does not contact the upper surface 42a or the side surfaces 42b, 42b.

[0059] Furthermore, the upper surface 42a and the side surfaces 42b, 42b of the plate member 42 do not contact the plate portion 292, forming a gap 29s. This gap 29s is located on the opposite side (the side of the through-hole 28f) from the hole 41h (see FIG. 7A).

[0060] Additionally, insulating portion 31b at the end of tube heater 31 is fitted into and held in hole 41h formed in choke 40. In this way, tube heater 31 is not supported by top wall 29, but is supported by hole 41h in choke 40. In other words, tube heater 31 is supported only by choke 40. Note that in this embodiment, only one side of tube heater 31 is illustrated and described, but the other side has a similar structure, is provided with a choke, and is supported by only the choke.

[0061] Furthermore, when the heating chamber 28 is heated, the top wall 29 becomes hot because the plate portions 292 and 293 are positioned close to the tube heater 31. On the other hand, the plate portion 291 becomes cold because it is positioned away from the tube heater 31. In this embodiment, the choke 40 is disposed outside the heating chamber 28, so the choke 40 is less susceptible to the heat from the tube heater 31. Furthermore, because the choke 40 is installed on the plate portion 291, which becomes cold, the choke 40 is less susceptible to the heat from the tube heater 31. Furthermore, because the choke 40 also serves to position the tube heater 31, even if the top wall 29 is deformed by the heat of the tube heater 31 and the position of the choke 40 is shifted, the relative position between the choke 40 and the tube heater 31 does not change.

[0062] <Another Modification of Heating Section> The cooking device 10 may be configured to include a heating section 30B (FIGS. 10 and 11) according to another modification, instead of the heating section 30 (FIG. 3) or the heating section 30A (FIG. 3). Here, in order to clearly explain the configuration of the heating section 30B, the configuration of the heating section 30Za in the cooking device 10Za of the first comparative example will first be described using FIG. 9, and then the configuration of the heating section 30B will be described using FIGS. 10 and 11. FIG. 9 is a schematic explanatory diagram of an example of the arrangement of the heating section 30Za in the cooking device 10Za of the first comparative example. FIG. 10 is a schematic explanatory diagram of an example of the arrangement of the heating section 30B according to another modification. FIG. 11 is a cross-sectional view of the heating section 30B according to another modification, viewed from the side.

[0063] 9, the cooking appliance 10Za of the first comparative example is configured to include a heating chamber 28 located below the interior of a housing outer frame 37, a heating unit 30Za located above the heating chamber 28, and a heating chamber top surface 28c separating the heating unit 30Za from the heating chamber 28. The heating unit 30Za is disposed in the space above the heating chamber top surface 28c, and includes a pipe heater 31 as a heat source, and sends heat to the heating chamber 28 via a through-hole 28h provided in the heating chamber top surface 28c.

[0064] In contrast, as shown in Fig. 10, the cooking appliance 10 has a heating chamber 28 located below the interior of the housing outer frame 37, a heating chamber top surface 28c located above the heating chamber 28, and a pipe heater 31 of the heating unit 30B incorporated into the heating chamber top surface 28c. The pipe heater 31 of the heating unit 30B is located closer to the heating chamber 28 than the underside of the heating chamber top surface 28c. Therefore, the heating unit 30B can send heat to the heating chamber 28 more efficiently than the heating unit 30Za of the cooking appliance 10Za of the first comparative example shown in Fig. 9, thereby improving heating performance.

[0065] Fig. 11 shows an enlarged view of the configuration of region R11 shown in Fig. 10. As shown in Fig. 11, the heating unit 30B has a tube heater 31 as a heat source. A heater guard 51 and a reflector 52 are provided around the tube heater 31. The heater guard 51 is disposed on the underside of the tube heater 31 and is a guard member that protects at least the heating chamber 28 side of the tube heater 31. The reflector 52 is disposed on the upper side of the tube heater 31 and is a member that reflects radiant waves emitted from the tube heater 31.

[0066] The heater guard 51 has a rounded portion 51a that is rounded (curved) concentrically with the tube heater 31 in a side view. The rounded portion 51a is an area that is arranged so as to be in contact (close contact) with or close to the surface of the tube heater 31. A plurality of through holes 51h are provided in the rounded portion 51a of the heater guard 51. The through holes 51h are arranged so as to radiate from the center of the tube heater 31, and shield microwaves during microwave heating and suppress electromagnetic wave leakage outside the oven.

[0067] The heater guard 51 and the reflector 52 have a rounded shape concentric with the tube heater 31, and each end extends horizontally. The horizontally extending parts are fixed to the top wall 29 of the heating chamber 28 by screws 36.

[0068] Cooking appliance 10B is configured such that pipe heater 31 of heating unit 30B is recessed closer to heating chamber space 28in than the underside of top wall 29. Therefore, cooking appliance 10B can efficiently send radiant heat emitted from pipe heater 31 to heating chamber space 28in, thereby improving heating performance.

[0069] Cooking appliance 10B also includes a reflector 52 arranged on the upper surface of pipe heater 31 so as to be in contact (close contact) with or close to pipe heater 31. Cooking appliance 10B also includes a heater guard 51 arranged on the lower surface of pipe heater 31 so as to be in contact (close contact) with or close to pipe heater 31, and heater guard 51 is either in partial contact (close contact) with top wall 29 or arranged close to top wall 29. This allows cooking appliance 10B to reduce the amount of heat transferred from the reflector 52 side to heating chamber outer space 28out and to increase the amount of heat transferred from the heater guard 51 side to heating chamber inner space 28in.

[0070] In addition, in cooking appliance 10B, heater guard 51 is configured as a perforated member having through holes 51h, and top wall 29 is configured as a non-perforated member having no through holes 51h, so that heater guard 51 and top wall 29 are configured as separate parts. In cooking appliance 10B, by using only heater guard 51, which is a perforated member, as a high heat-resistant part, it is possible to reduce the cost of parts.

[0071] In addition, a high-emission paint 29c is provided on the underside of the top wall 29. This allows the cooking appliance 10B to further improve its heating performance. Furthermore, the cooking appliance 10B can apply the high-emission paint 29c, which is heat-sensitive, to the top wall 29, which is a non-porous member. This cooking appliance 10B can prevent the top wall 29 from receiving direct waves from the pipe heater 31, thereby suppressing local temperature increases. Furthermore, the cooking appliance 10B can improve its heating performance because the high-emission paint 29c can highly efficiently reflect the heat waves from the pipe heater 31.

[0072] <Another Modification of the Heating Section> The cooking device 10 may be configured to include a heating section 30C ( FIG. 13 ) according to another modification, instead of the heating section 30 ( FIG. 3 ) or the heating section 30A ( FIG. 3 ). To clearly explain the configuration of the heating section 30C, the configuration of the heating section 30Zb in the cooking device 10Zb of the second comparative example will first be described using FIG. 12 , and then the configuration of the heating section 30C will be described using FIG. 13 . The heating section 30Zb ( FIG. 12 ) and the heating section 30C ( FIG. 13 ) each use a planar heater as a heat source. FIG. 12 is an explanatory diagram of a problem with the cooking device 10Zb of the second comparative example, which uses a planar heater for the heating section 30Zb. FIG. 13 is a cross-sectional side view of the heating section 30C of the cooking device 10 according to the modification using a planar heater. The cooking device 10Zb of the second comparative example using a planar heater and the cooking device 10 according to the modified example both heat food by radiant heating from the planar heater above the food.

[0073] As shown in Fig. 12, the cooking appliance 10Zb of the second comparative example includes a planar heater 32, a heat insulating material 63, and a heater presser 64 on the top wall 29. The planar heater 32, the heat insulating material 63, and the heater presser 64 are fixed to an upper wall 294a of the top wall 29 with screws 65. The planar heater 32 has a configuration in which a nichrome wire 62 is sandwiched between two pieces of mica 61, and generates heat when power is supplied to the nichrome wire 62 from a power source 66. In the heating unit 30Zb of the cooking appliance 10Zb, the upper wall 294a of the top wall 29 is deformed in a thermal deformation direction F11 (downward) due to heating by the planar heater 32, which may result in the formation of an air layer 67 between the top wall 29 and the planar heater 32. When the upper wall 294a of the top wall 29 is deformed in the thermal deformation direction F11 (downward), the planar heater 32 is separated from the top wall 29. Therefore, the heating performance of the cooking device 10Zb may be reduced, as in Patent Document 5, for example.

[0074] As shown in FIG. 13, a heating section 30C of the cooking device 10Zb is different from the heating section 30Zb of the cooking device 10Zb in that the top wall 29 is composed of an upper wall 295a and a side wall 295b.

[0075] That is, the heating section 30C of the cooking device 10 is configured such that the upper wall 295a and the side wall 295b are separate bodies. The heating section 30C of the cooking device 10 is also configured such that the upper wall 295a and the planar heater 32 are in close contact with each other.

[0076] In the heating unit 30C, the upper wall 295a and the planar heater 32 are in close contact with each other, but a gap may be formed between the upper wall 295a and the planar heater 32, potentially forming an air layer 67 in the gap. However, even if the air layer 67 is formed, the heating unit 30C has the upper wall 295a and the side wall 295b configured separately, and the portion shown as region R21 is separated. This allows thermal deformation of the upper wall 295a due to heating by the planar heater 32 to escape in the thermal deformation direction F12 (horizontal direction). Therefore, the heating unit 30C can maintain the distance between the upper wall 295a and the planar heater 32, thereby maintaining heating efficiency.

[0077] Furthermore, the heating unit 30C can improve heating performance because the upper wall 295a and the planar heater 32 are in close contact with each other, allowing radiant heat to be efficiently sent from the upper wall 295a to the heating chamber 28. Furthermore, the heating unit 30C does not have a through-hole in the upper wall 295a, which improves cleaning ease.

[0078] The cooking device 10 including such a heating unit 30C can improve the cleaning properties of the heating chamber 28 while ensuring high heating power.

[0079] The cooking device 10 according to this embodiment is intended to ensure high heating power while improving the ease of cleaning the heating chamber 28. The cooking device 10 according to this embodiment has the following features.

[0080] <Major Features of Cooking Device for Solving First Problem> (1) As shown in Fig. 3 , cooking device 10 according to this embodiment includes a heating chamber 28 that stores food inside main body 11, a plurality of tube heaters 31 that penetrate heating chamber 28 and irradiate heating chamber 28, two or more protective glasses 33 that protect each of tube heaters 31, and a reflector 34 that reflects radiant heat T31 from tube heaters 31. Cooking device 10 is arranged with reflector 34, tube heaters 31, and protective glasses 33 in this order from the outside of heating chamber 28.

[0081] In the heating cooker 10 according to this embodiment, the protective glass 33 is arranged in a divided manner, which reduces the volume of the protective glass and therefore the heat capacity, and therefore reduces the amount of heat absorbed by the protective glass 33, thereby improving heating performance.

[0082] (2) As shown in FIG. 3 , in the cooking device 10 according to this embodiment, the reflecting plate 34 is configured to contact the top wall 29 at the intermediate portion 29 a between adjacent tube heaters 31 .

[0083] The cooking device 10 according to this embodiment can efficiently transfer heat from the reflector 34 to the heating chamber 28 via the intermediate portion 29a. Therefore, the cooking device 10 can improve the ease of cleaning the heating chamber 28 while ensuring high heating power.

[0084] (3) As shown in FIG. 3 , in the cooking device 10 according to this embodiment, the top wall 29 is folded back at the folded back portion 29 b to come into contact with the protective glass 33 .

[0085] The cooking appliance 10 according to this embodiment can prevent the user's fingers from coming into contact with the edge of the top wall 29 during cleaning.

[0086] (4) As shown in FIG. 3, the cooking device 10 according to this embodiment further includes a metal plate 35 having a through hole 35h, and is provided with a reflector 34, a tube heater 31, the metal plate 35, and a protective glass 33 in this order from the outside to the inside of the heating chamber 28.

[0087] The cooking appliance 10 according to this embodiment can prevent the re-reflected waves (radiant heat T31) from repeatedly passing through the protective glass 33. Therefore, the cooking appliance 10 can efficiently send the re-reflected waves (radiant heat T31) to the heating chamber 28, improving heating performance. Furthermore, the cooking appliance 10 can be easily cleaned because the underside of the metal plate 35 (punched metal, metal mesh, or the like) is covered with the protective glass 33.

[0088] (5) As shown in FIG. 3 , in the cooking device 10 according to this embodiment, the metal plate 35 is fitted to the top wall 29 above the protective glass 33 and is positioned so as to be in contact (close contact) with or in close proximity to the protective glass 33.

[0089] In the cooking appliance 10 according to this embodiment, the fitting portion between the metal plate 35 and the top wall 29 does not get in the way of cleaning, making the cooking appliance 10 easy to clean. Also, in the cooking appliance 10, the metal plate 35 comes into contact with the protective glass 33, so that heat from the metal plate 35 can be efficiently transmitted to the heating chamber 28 via the protective glass 33, improving heating performance.

[0090] (6) As shown in FIG. 4, in the heating cooker 10 according to this embodiment, the reflecting plate 34 may be configured to have a reflecting surface portion 34a that reflects the radiant heat T31 from the tube heater 31 and a strength portion 34b that holds the reflecting surface portion 34a.

[0091] In the cooking appliance 10 according to this embodiment, the reflecting surface portion 34a can be easily formed into any shape, and the reinforcing portion 34b can hold the reflecting surface portion 34a so that it does not deform.

[0092] (7) As shown in FIG. 4 , the cooking device 10 according to this embodiment has the heat insulating material 38 above the reflecting plate 34 .

[0093] The cooking device 10 according to this embodiment can reduce the amount of heat transferred from the reflecting plate 34 to the housing outer frame 37 and increase the amount of heat transferred from the reflecting plate 34 to the heating chamber 28. This allows the cooking device 10 to improve its heating performance.

[0094] <Major features of the cooking device for solving the second problem> (1) As shown in Figures 5 and 6, the cooking device 10 according to this embodiment includes a heating chamber 28 for storing food inside the main body 11, a tube heater 31 that is disposed penetrating the top wall 29 (heating chamber wall) and heats the inside of the heating chamber 28, and a choke 40 that blocks electromagnetic waves leaking from through-hole 28f that penetrates the top wall 29 (heating chamber wall). The choke 40 is installed on a plate portion 291 (surface of the heating chamber wall) that is parallel to the tube heater 31 outside the heating chamber 28, and holds the tube heater 31 on a side portion 41d (one surface) of the choke 40.

[0095] In the cooking appliance 10 according to this embodiment, the chalk 40 is disposed outside the heating chamber 28, thereby making the chalk 40 less susceptible to the effects of heat within the heating chamber 28. Furthermore, because the chalk 40 also serves to position the tube heater 31, even if the position of the chalk 40 shifts due to thermal deformation of the plate portion 291 (wall surface) of the heating chamber 28, the relative positions of the tube heater 31 and the chalk 40 do not change, making it possible to maintain the electromagnetic wave shielding effect. Furthermore, because the chalk 40 is installed on the plate portion 291 (wall surface) of the heating chamber 28 parallel to the tube heater 31, the chalk 40 is installed on the plate portion 291 (wall surface) that is away from the tube heater 31 and has a lower temperature, making the plate portion 291 (wall surface) less susceptible to thermal deformation, thereby making it possible to obtain the electromagnetic wave shielding effect.

[0096] (2) As shown in FIG. 8, in the cooking device 10 according to this embodiment, the end of the tube heater 31 is held in a hole 41h formed through the choke 40, and the hole 41h has a shape (e.g., an approximately semicircular shape) that prevents the tube heater 31 from rotating.

[0097] In the cooking device 10 according to this embodiment, the position of the pipe heater 31 relative to the choke 40 does not change, and therefore, a radio wave shielding effect can be obtained.

[0098] (3) As shown in FIGS. 5 and 6, in the cooking device 10 according to this embodiment, the pipe heater 31 is disposed with a gap 29s between it and the through-hole 28f.

[0099] The cooking device 10 according to this embodiment can prevent the heat from the pipe heater 31 from being transmitted to the top wall 29 (heating chamber wall).

[0100] 11 , the cooking device 10B according to the present embodiment includes a heating chamber 28 that stores food inside the main body 11, a heating unit 30B that irradiates the heating chamber 28, and a heater guard 51 that is disposed between a wall surface of the heating chamber 28 (top wall 29 in the illustrated example) and a pipe heater 31 that is a heat source for the heating unit 30B and serves as a guard member that protects at least the heating chamber 28 side of the pipe heater 31. The heater guard 51 has a plurality of through holes 51h, and is disposed in partial contact with the wall surface of the heating chamber 28 or in close proximity to the wall surface of the heating chamber 28.

[0101] In the cooking device 10B according to this embodiment, the heater guard 51 is disposed in partial contact with the wall surface of the heating chamber 28 or in close proximity to the wall surface of the heating chamber 28. This cooking device 10B can increase the amount of heat transferred from the heater guard 51 to the wall surface of the heating chamber 28. Therefore, the cooking device 10B can efficiently deliver heat to the heating chamber 28. Furthermore, even if food adheres to and clogs the through-holes 51h of the heater guard 51, the cooking device 10B can cook the food to completion. This eliminates the need for cleaning to remove food stains. Therefore, the cooking device 10B can improve the cleanability of the heating chamber 28 while maintaining high heating power. Furthermore, the cooking device 10B can protect the tube heater 31 with the heater guard 51.

[0102] (2) As shown in FIG. 11 , in the cooking device 10B according to this embodiment, the heater guard 51 has the through-holes 51 h only in the area close to the surface of the pipe heater 31 .

[0103] The cooking appliance 10B according to this embodiment can limit the area where food adheres and clogs the through-holes 51h, thereby improving cleanability.

[0104] (3) As shown in FIG. 11, in the heating cooker 10B according to this embodiment, the heater guard 51 is configured as a perforated member having through holes 51h, and the wall surface of the heating chamber 28 (the top wall 29 in the illustrated example) is configured as a non-perforated member having no through holes 51h, and the heater guard 51 and the wall surface of the heating chamber 28 are configured as separate parts.

[0105] In the cooking appliance 10B according to this embodiment, only the heater guard 51, which is a perforated member, is a highly heat-resistant component, thereby reducing component costs. Furthermore, the cooking appliance 10B can have a high-radiation paint 29c, which is heat-sensitive, applied to the wall surface of the heating chamber 28, which is a non-perforated member. This cooking appliance 10B can prevent the wall surface of the heating chamber 28 from receiving direct waves from the tube heater 31, thereby suppressing localized temperature increases. Furthermore, the cooking appliance 10B can improve heating performance by efficiently reflecting the radiant heat from the tube heater 31 with the high-radiation paint 29c.

[0106] (4) As shown in FIG. 11, the cooking device 10B according to this embodiment includes a reflector 52 at a position where the tube heater 31 is sandwiched between the tube heater 31 and the heating chamber 28.

[0107] The heating cooker 10B of this embodiment can improve heating performance by reflecting the radiant heat emitted from the tube heater 31 to the heating chamber outer space 28out side to the heating chamber inner space 28in side using the reflector plate 52.

[0108] (5) As shown in Fig. 11 , in the cooking device 10B according to this embodiment, the pipe heater 31 has a substantially circular cross-sectional shape in side view. The heater guard 51 has a rounded portion 51a that is rounded (curved) concentrically with the pipe heater 31 in side view, and through holes 51h that are radially arranged from the center of the pipe heater 31 are provided in the rounded portion 51a.

[0109] The cooking appliance 10B according to this embodiment is configured such that through holes 51h are provided along the radiation direction of radiant heat emitted from the tube heater 31. The cooking appliance 10B can reduce the amount of radiant waves reflected by the inner wall of the heater guard 51 and efficiently send the radiant waves toward the heating chamber inner space 28in, thereby improving heating performance.

[0110] <Major Features of Cooking Device for Solving the Fourth Problem> (1) As shown in Fig. 13 , cooking device 10 according to this embodiment includes heating chamber 28 that stores food inside main body 11, and planar heater 32 that irradiates heating chamber 28. Heating chamber 28 has upper wall 295a and side wall 295b that are configured as separate bodies, and upper wall 295a and planar heater 32 are in close contact with each other.

[0111] The cooking appliance 10 according to this embodiment can dissipate thermal deformation of the upper wall 295a caused by heating by the planar heater 32 in the thermal deformation direction F12 (horizontal direction). Therefore, the cooking appliance 10 can maintain the distance between the upper wall 295a and the planar heater 32, thereby maintaining heating efficiency. Furthermore, the cooking appliance 10 does not have a through-hole in the upper wall 295a, which improves cleanability. Therefore, the cooking appliance 10 can improve the cleanability of the heating chamber 28 while ensuring high heating power.

[0112] (2) As shown in Fig. 13, the cooking device 10 according to this embodiment further includes a heater presser 64 that presses down and fixes the planar heater 32 from above. The heater presser 64 is configured to surround the side and top surfaces of the planar heater 32.

[0113] In the cooking appliance 10 according to this embodiment, the heater presser 64 can prevent leakage of electromagnetic waves.

[0114] (3) As shown in FIG. 13, in the cooking device 10 according to this embodiment, the heater presser 64 is fixed to the side wall 295b.

[0115] In the cooking appliance 10 according to this embodiment, the flat heater 32 can be firmly fixed.

[0116] <Modification Example 1 of Heating Unit (Reference Example 1)> A modification of the heating unit will be described below as a reference example. Fig. 14 shows a three-dimensional assembly diagram of the heating unit attached to a cooking device according to Reference Example 1 of the present invention. The lower part of Fig. 14 shows the heating chamber upper wall surface 29 (heating chamber ceiling surface; hereinafter simply referred to as the wall surface) that forms the heating chamber 28 of the cooking device 1, and an opening 296c1 is formed in the wall surface 29. A protective glass 331 is positioned above the opening 296c1 to cover it. Mounting holes 296c2 and 296c3 are provided around the opening 296c1.

[0117] Two sets of fasteners 361b are arranged on the upper surface of the protective glass 331 at the left and right positions in the figure, and the protective glass 331 is sandwiched between the wall surface 29 and the fasteners 361b, and the protective glass 331 is fixed to the wall surface 29 by using holes in the fasteners 361b1 and mounting holes 296c2 around the opening 296c1. Also, a reflective box 341 that houses the heater 31 is positioned above the protective glass 1a, and the reflective box 341 is fixed to the wall surface 29 by using holes in the reflective box 341 formed in an attachment portion 341a of the reflective box 341 and other mounting holes 296c3 around the opening 296c1.

[0118] In the example of Figure 14, mounting holes are provided and fastened with bolts and nuts, but screws may also be used to fasten directly between the holes. In this document, these are collectively referred to as screw fastening.

[0119] With this configuration, the protective glass 331, heater 31, and reflector box 341 are arranged in this order on the wall surface 29 of the heating chamber 28 outside the heating chamber. Fig. 14 shows one example of attachment, and the attachment method of the protective glass 331 and reflector 341 is not limited to that shown in Fig. 14. The key is to arrange them in this order, and they can be arranged as shown in Fig. 15A, 15B, or 15C, for example.

[0120] 14, the protective glass 331 is fixed to the wall surface 29 by screwing with a bolt and nut using the hole 361b of the fastener 361 and the mounting holes 296c2 around the opening 291, and the reflective box 341 is fixed to the wall surface 29 by screwing with a bolt and nut using the hole 341b of the reflective box 341 and other mounting holes 296c3 around the opening 296c2. It is preferable that the reflective plate 341 be formed in advance as a unit (reflective box) that incorporates the heater 31.

[0121] 15B and 15C show that the fixing portion 361c between the wall surface 29 and the protective glass 341 is adhesively fixed with silicone, whereas in FIG. 4c, the protective glass 331 is fitted into the opening 296c1 and the fixing portion 361c is adhesively fixed with silicone.

[0122] According to the first embodiment of the present invention, protective glass 331 is provided on a portion of wall surface 29 of heating chamber 28, preventing moisture, oil, seasonings, etc. from food from contaminating the heater, and even if protective glass 331 becomes contaminated, it can be cleaned with a cloth or the like from inside heating chamber 28. Furthermore, since there are few irregularities, cleaning is easy, and the transparent plate can be cleaned from the inside of the heating chamber, resulting in excellent cleanability.

[0123] <Modification 2 of the Heating Section (Reference Example 2)> Reference Example 1 described a system in which no perforated metal was provided. However, depending on the heater 31, it may be better to provide a perforated metal function. In a cooking appliance, a microwave power source is provided on the underside of the heating chamber. However, some heaters generate heat using microwaves, so in these cases it is better to provide a perforated metal function. Specifically, it is better to provide a perforated metal function in the case of a carbon heater, a halogen heater, a graphite heater, or a quartz tube heater.

[0124] 16A, 16B, and 16C show the configurations of Figures 15A, 15B, and 15C, in which a perforated metal 351 is provided, and in each case, the perforated metal 351 is disposed between the protective glass 331 and the heater 31. According to Reference Example 2 of the present invention, heating of the heater by microwaves can be prevented while maintaining cleanability.

[0125] <Modification Example 3 of the Heating Unit (Reference Example 3)> Reference Example 3 describes positioning during the three-dimensional assembly shown in FIG. 14 . It may be advantageous to provide an additional positioning portion for the protective glass on the wall surface 29 of the heating chamber. FIGS. 17A, 17B, and 17C show the configurations of FIGS. 15A, 15B, and 15C, with a positioning portion 361d provided on the wall surface 29. FIGS. 18A, 18B, and 18C show the configurations of FIGS. 16A, 16B, and 16C, with a positioning portion 361d provided on the wall surface 29. Providing a convex positioning portion 361d on the wall surface 29, for example, so as to surround the outer periphery of the fixing portion 361c, facilitates positioning of the protective glass 331 and improves assembly of the heating unit.

[0126] <Modification Example 4 of the Heating Unit (Reference Example 4)> Reference Example 4 is also a device for facilitating positioning during the three-dimensional assembly shown in FIG. 14 . While Reference Example 4 provided a convex positioning portion 361d on the wall surface 29, Reference Example 4 provides a recess 29t on the wall surface 29 of the heating chamber, as shown in FIG. 19 . The wall surface 29 of the heating chamber may also be provided with a recess 29t into which a protective glass is fitted. Fitting the protective glass in this recess 29t facilitates positioning of the protective glass and improves the assembly of the heating unit. The protective glass fitted in the recess 29t can be fixed by screws or adhesive.

[0127] The present invention is not limited to the above-described embodiment, and includes various modifications. For example, the above-described embodiment has been described in detail to clearly explain the present invention, and is not necessarily limited to a configuration including all of the described configurations. Furthermore, it is possible to replace part of the configuration of the embodiment with another configuration, and it is also possible to add another configuration to the configuration of the embodiment. Furthermore, it is possible to add, delete, or replace part of each configuration with another configuration.

[0128] DESCRIPTION OF SYMBOLS 10, 10Za, 10Zb Cooking appliance 11 Main body 28 Heating chamber 28f, 28h, 35h, 51h Through hole 28in Heating chamber inner space 28out Heating chamber outer space 29 Top wall 29a Middle portion 29b Folded portion 29c High radiation paint 29p Protrusion 29s Gap (space) 291, 292, 293 Plate portion 294a, 295a Top wall 295b Side wall 30, 30A, 30B, 30C, 30Za, 30Zb Heating portion 31 Tube heater (heat source) 31a Tube portion 31b Insulating portion 31c Electric wire (lead wire) 32 Planar heater (heat source) 33 Protective glass 34, 52 Reflector 34a Reflective surface portion 34b Strengthening portion 34ba, 34bb, 34bc Fixing portion 35 Metal plate 36, 43 Screw 37 Housing outer frame 38 Heat insulating material 40 Choke 41, 42 Plate member 41a, 42a Top surface portion 41b, 42b Side surface portion 41c, 42c Bottom surface portion 41d Side surface portion (one side of choke) 41e Screw insertion hole 41h Hole 41s Space 42d Screw insertion hole 42s Space 51 Heater guard (guard member) 51a Round portion 61 Mica 62 Nichrome wire 63 Heat insulating material 64 Heater holder 65 Screw 66 Power source 67 Air layer T11 Heat conduction T31 Radiant heat

Claims

1. A cooking device comprising: a heating chamber for storing food inside the body; a plurality of tube heaters which penetrate said heating chamber and irradiate said heating chamber; two or more protective glasses which protect each of the tube heaters; and a reflector which reflects radiant heat from the tube heaters, the reflector, the tube heaters and the protective glass being arranged in this order from the outside of said heating chamber.

2. A cooking device according to claim 1, characterized in that the reflector is in contact with a top wall of the heating chamber between adjacent ones of the tube heaters.

3. A cooking device according to claim 1, characterized in that the top wall is folded back to contact the protective glass.

4. A cooking device as claimed in claim 1, further comprising a metal plate having a through hole, the reflector, the tube heater, the metal plate and the protective glass being arranged in this order from the outside to the inside of the heating chamber.

5. A cooking device as described in claim 1, further comprising a metal plate having a through hole, the metal plate being fitted into the top wall above the protective glass and being positioned so as to be in contact with or in close proximity to the protective glass.

6. A cooking device according to claim 1, characterized in that the reflecting plate has a reflecting surface that reflects radiant heat from the tube heater and a strength portion that holds the reflecting surface.

7. A cooking device according to claim 1, characterized in that it has a heat insulating material above the reflecting plate.

Images