Plate for cooking

Abstract

To inhibit heat conduction to the edge of a plate, prevent the temperature drop of the effective cooking surface on the surface of the plate where cooking is performed, and suppress heat loss caused by heat dissipation outside the effective cooking surface of the plate.SOLUTION: In a cooking plate 1 of a cooking device in which food materials are placed on the surface and heated from the back side to cook, an effective cooking surface where cooking is performed is set in the center of the surface of the plate 1, and a recess 20 with a rectangular cross section and reduced thickness is provided on the back side of the end of the plate 1 to inhibit heat conduction from the effective cooking surface to the end and suppress heat loss.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a cooking plate used in cooking equipment for heating food ingredients.

Background Art

[0002] A cooking plate used in cooking equipment in the commercial or household field is a hot plate for performing cooking using energy such as electricity, gas, or charcoal as a heat source, and is used for cooking such as okonomiyaki, steak, grilled meat, takoyaki, Genghis Khan, and baked confectionery. As materials for the plate, metal plates such as steel, cast iron, stainless steel, copper, or aluminum, wire meshes, non-metal plates such as ceramic plates (including ceramic plates and crystallized glass plates) or stone plates are used. As a manufacturing method, the main part is manufactured by casting, forging, machining, etc., and is assembled using welding or screws in part. The shape of the cooking surface is made according to the cooking method and the finished shape. Steak, okonomiyaki, or hot cakes are approximately flat plates, grilled meat and grilled seafood are perforated flat plates (so-called Rostl), wire meshes, or shapes with a large number of irregularities of about several millimeters, Genghis Khan, etc. are bowl-shaped, and takoyaki, Imagawa-yaki, and other confectionery are plate-shaped with a plurality of depressions.

[0003] In addition, the cooking plate for heating is molded into a square or round shape in a plan view according to the shape of the cooking equipment using it, and in terms of size, there are those as small as about 0.3 m for household use and large cooking counters with a long side exceeding 3 m for commercial use.

[0004] Furthermore, many of these cooking plates for heating are generally flat plate-shaped, and even if they are three-dimensional, grooves for separating cooking juices and fats and oils associated with cooking are cut on the outer periphery of the plate only to the extent outside the part where the food ingredients are actually placed and cooked, and there has been little device for the shape for the main purpose of energy saving.

[0005] For example, Patent Document 1 describes providing a protection part for preventing the backflow (spreading to the back surface) of oil and gravy on the back surface. The first backflow prevention part is uneven with a zigzag cross-section, and the second backflow prevention part is a convex protrusion downward. It is assumed that the oil and gravy flow from the opening on the cooking surface of the heating cooking plate to the back surface and spread, and the second backflow protection part is provided upstream of the flow, and the first backflow protection part is provided downstream. The first backflow protection wall is uneven with a zigzag shape within the range of reducing the thickness of the plate with a triangular wave cross-section. As long as it is uneven, it means that a plurality of concave parts and convex parts are continuous. Also, the second backflow protection wall has a convex shape downward in the direction of increasing the thickness of the heating cooking plate.

[0006] In addition, Patent Document 2 provides a through-hole in the central part of the heating cooking plate to improve the discharge of gravy or oil, and a plurality of ribs are provided on the through-hole for bridging. A downward convex rib for preventing the backflow of gravy is formed around the through-hole of the plate. Patent Document 3 describes unevenness with a zigzag cross-section called a heat replenishment part. The unevenness has a triangular wave shape that increases and decreases the thickness around the average thickness of the heating cooking plate.

[0007] In Patent Document 4, the heating part (heater) is centrally arranged in the plate, and the surrounding is partially heat-shielded by a back groove, and the outer surface of the back groove is used as a heat preservation part. Therefore, the position where the back groove is formed in the plate necessarily requires a mounting space as a heat preservation part, so it is set to be 5 to 10 cm from the end.

[0008] In Patent Document 5, a groove with a semicircular cross-section is formed on the back surface of the plate along the outer edge of the heater to suppress heat dissipation to the surroundings, accelerate the temperature rise of the cooking surface, and increase the maximum temperature.

[0009] In Patent Document 6, for the purpose of reducing heat loss to the outer peripheral part of the plate, a recess on the back surface is provided at the boundary between the cooking area and the flange. Further, a low heat conduction member such as stainless steel is fitted into the recess. The low heat conduction member is not an ordinary heat insulating material but a low heat conduction metal, and by protruding it from the lower surface of the plate, it is also used as legs or a pot mat when lifting only the plate and placing it on the table. Incidentally, the thermal conductivities of still air and stainless steel (SUS304) are 0.0242 W / mK and 16.0 W / mK respectively, and the fitting of the low heat conduction member (SUS304) cannot suppress heat conduction.

[0010] In Patent Document 7, a temperature control recess (a part with a reduced thickness) is provided at the end of a grill plate (cooking plate) for the purpose of raising the temperature at the end and expanding the cooking surface. The heating part and the end of the temperature control recess overlap in a cross-sectional view.

[0011] Patent Document 8 describes providing a thin part with a thickness of t for absorbing thermal strain during casting or use of an electric hot plate (cooking plate). For example, it is to provide grooves with a rectangular cross-section at a distance of the thickness t on the front and back of the plate. However, in order to form the thin part, a plurality of grooves are required on the front and back, and for absorbing the strain, the thickness t must be less than the thickness of the plate to be meaningful.

Prior Art Documents

Patent Documents

[0012]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

Patent Document 8

Summary of the Invention

Problems to be Solved by the Invention

[0013] In the present invention, by providing a portion with reduced thickness at the back end of the plate, heat conduction to the end of the plate is inhibited, preventing a temperature drop in the effective cooking surface where cooking is performed on the surface of the plate, and suppressing heat dissipation outside the effective cooking surface of the plate to avoid heat loss.

[0014] Also, it is an object to suppress overheating of the housing of cooking equipment in contact with the cooking plate, facilitate compliance with the upper limit temperature regulated by public standards, enable the application of inexpensive and easily moldable materials such as resins with poor heat resistance, or suppress discoloration of stainless steel such as SUS304 that discolors due to temperature rise to maintain appearance, and further partially inhibit the backflow and spread of cooking juices and fats from the plate end face to the back surface.

Means for Solving the Problems

[0015] In a cooking plate for a cooking appliance that places food on the surface of the plate and performs cooking by heating from the back or inside of the plate, a concave portion with a rectangular cross-section and reduced thickness is provided at the outer edge of the back surface of the effective cooking surface set on the surface of the plate. The concave portion reduces the heat capacity and inhibits heat conduction outside the effective cooking surface.

[0016] The heat diffusion in a solid, that is, the heat transfer amount by heat conduction, is proportional to the cross-sectional area of the path and inversely proportional to the length. By providing a concave portion with a rectangular cross-section and reduced thickness at the back end of the effective cooking surface of the plate, the cross-sectional area of the heat passing toward the plate end is reduced at that portion. Therefore, heat conduction from the central portion to the end of the plate is inhibited, and the amount of heat reaching the end outside the concave portion is proportionally reduced.

[0017] In addition, the cooking juice and oil that turn from the end face to the back face of the plate need to go up and down vertically in the concave portion on the back face, and the effect of gravity or the effect due to the increase in distance overcomes the surface tension, suppressing the spread of the cooking juice and oil.

[0018] The thickness of the plate in the concave portion is reduced in thickness from the back face to a rectangular cross-section, so that the thinnest part becomes flat, the cross-section becomes wider than that of the concave portion with other shapes, and it becomes the longest distance as the heat conduction path, so that the heat conduction inhibition effect becomes the maximum. Incidentally, when reducing the thickness to a semi-circular cross-section, the thinnest part becomes point-like. In the central part which is inside the concave portion, the amount of heat dissipated by heat conduction decreases, so the temperature rises and the thermal function as an effective cooking surface is enhanced.

[0019] When the cooking plate is heated from its back face by an electric sheath heater, a lamp heater, or a flame such as gas, a temperature distribution occurs in the cross-section of the plate where the back face is high and the temperature decreases toward the surface. In addition, since the heating is performed in a planar manner at the central part of the plate where normal cooking is carried out, a temperature distribution occurs on the surface of the plate where the central part is hotter than the end part, and heat diffuses (heat conduction) from the central part of the plate toward the end part.

[0020] However, the heat conduction from the central part toward the end part, due to the above-described temperature distribution between the front and back faces, the conduction from the back face where the temperature difference is large is larger than that from the surface, and the heat transfer inhibition based on the cross-sectional area reduction effect due to reducing the thickness is more effective when forming the concave portion on the back face than on the surface. When an electric resistance wire heater is cast inside the plate or in the case of IH (Induction Heating) heating, since heat is generated inside, although the effect is inferior to the case of back face heating, the heat transfer inhibition effect to the surroundings is still maintained.

[0021] The effective cooking surface is in the shape of a flat plate, a perforated flat plate, or a flat plate with a plurality of depressions formed thereon. The plate forms the effective cooking surface on the surface inside the recess by reducing the thickness at the rear end. Although the periphery of the effective cooking surface is kept planar, depending on the type of cooking, the shape of the effective cooking surface may be deformed. For example, steaks, okonomiyaki, or hot cakes, etc. are in the basic flat plate shape, but for grilled meat or grilled seafood, a perforated flat plate (so-called lostrol) with elongated holes opened, a shape with a large number of irregularities (ribs) of about several millimeters, or a wire mesh, for Mongolian barbecue, etc. a bowl-shaped plate, and for takoyaki, imabari-yaki and other baked confectioneries, a plate with a plurality of depressions is used. Even when such a deformation is applied to the effective cooking surface, by providing a portion with reduced thickness on the back surface of the outer edge of the effective cooking surface, the same effect as that of a flat plate is exhibited.

[0022] The lower end of the outer periphery of the plate is located at the same height as the back surface of the effective cooking surface or lower than the back surface. That is, the thickness of the outer periphery is increased so that the lower end of the outermost periphery of the entire plate is at the same position as or lower than the lower end of the effective cooking surface. As a means for increasing the thickness, it can be realized by integral molding by casting or forging, grooving by machining, or the like.

[0023] In this configuration, since the heat capacity and surface area of the outer periphery of the plate increase, the temperature of that portion decreases. At the same time, due to the increase in the irregularities on the back surface, it is possible to more effectively prevent the cooking juice and oil from spreading around on the back surface of the plate. Further, when implementing the present invention as a specification change, since the shape of the outer periphery can be the same as before the thickness is reduced, compatibility with the conventional plate can be maintained.

[0024] The upper end of the outer periphery of the plate is made slightly higher than the effective cooking surface so as to block fats and oils generated during cooking. If the end of the plate is flat, the cooking liquid and fats and oils may spread on the plate surface and part of them may turn to the back surface. To prevent this, it is effective to increase the height of the plate end face. On the other hand, increasing the height of the end part unnecessarily results in cost increase. In some household hot plates, for example, in order to be able to cook simple pot dishes such as sukiyaki, the plate end face is called a flange and its height is made 50 mm or more, similar to a pot. However, when the heating cooking equipment does not handle soup cooking, it is sufficient to have a height that blocks fats and oils, gravy, etc. associated with cooking to a minimum. The height of the plate end is set slightly higher than the upper end of the end of the effective cooking surface and is made higher than the effective cooking surface by a dimension of 1.5 times or less the thickness of the effective cooking surface. Preferably, it is ideally about 0.5 times to 1.5 times the thickness of the effective cooking surface higher. At this height, cooking utensils (chopsticks, turners, ladles, knives, forks, tongs, etc.) will not hit and will not interfere with the cooking operation. In addition, if there are fats and oils that spread to the back surface exceeding this height, by lowering the lower end of the outer periphery of the plate as described above, it is prevented from spreading to the back surface.

Advantages of the Invention

[0025] The present invention is based on the results of development to develop the effects, starting from the fact that the inventor discovered during experiments that when grooving is performed from the back surface near the end face of the heating cooking plate, the high-temperature part (heating cooking surface) of the surface spreads. The effects of reducing the thickness of the plate so as to have a rectangular cross-section are as follows. 1. An energy-saving effect by suppressing heat escape (diffusion and dissipation) around the plate end and reducing the amount of heat applied 2. An improvement effect of the cooking function in which the temperature of the effective cooking surface rises due to heat loss from the plate end and a decrease in heat capacity 3. When the portion with the reduced thickness on the back surface of the plate is grooved, it can lower the temperature at the plate end, facilitate heat dissipation from the member (usually the housing) in contact with the plate, and conform to temperature regulation, or convert the contact member and the secondary contact member to a low heat-resistant material 4. When the portion with the reduced thickness on the back surface of the plate is grooved, it can lower the temperature at the plate end and reduce the risk of burns when accidentally touching the plate end or the contact member (improving safety)

Brief Description of the Drawings

[0026]

Figure 1

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Figure 13

Best Mode for Carrying Out the Invention

[0027] Fig. 1 shows a cooking appliance using a cooking plate according to the first embodiment. This cooking appliance is a gas grill, and a flat cooking plate 1 is placed on an appliance body 3 by legs 2 made of socket head cap screws. In the figure, 4 is leg rubber, 5 is a gas appliance plug, 6 is a special-shaped joint clip, 7 is a bottom plate, 8 is a burner base, 9 is an igniter, 10 is a damper, 11 is a gas connection port, 12 is a thermostat, 13 is a heat reflecting plate, 14 is a gas burner, 15 is an oil can, 16 is a heat insulating plate, and 17 is a burner frame plate.

[0028] As shown in Fig. 2, the plate 1 is a flat plate having a rectangular shape in plan view. At the end of the back surface of the plate 1, a concave portion 20 having a rectangular cross-sectional shape with a reduced thickness is provided, and an effective cooking surface is set on the surface of the plate 1 according to the concave portion 20. The concave portion 20 reduces the heat capacity outside the effective cooking surface and inhibits heat conduction to the outside of the effective cooking surface. The effective cooking surface is a region that also becomes high temperature on the surface of the plate 1, and the food to be cooked by heating is placed on the effective cooking surface.

[0029] A plate 1 having a relatively large thickness is used, and a thickness of about 4 mm to about 30 mm is often used. As the material, it is a metal plate such as steel, cast iron (including various ferroalloys), stainless steel (SUS304, SUS430, etc.), copper (including copper alloys), or aluminum (including aluminum alloys). Alternatively, non-metal plates such as wire meshes, ceramic plates (including ceramic plates and crystallized glass plates), or stone plates can be mentioned. As the manufacturing method, it is made by casting, forging, machining, etc., and is assembled using welding, screws, etc. in part. The application is cooking by heating such as okonomiyaki, steak, grilled meat, takoyaki, Genghis Khan, baked confectionery, etc., and the shape of the effective cooking surface is made according to the finished shape of each cooking.

[0030] Near the end of the back surface of the plate 1, a groove is formed over the entire circumference, and this groove is made into a recess 20 with a reduced thickness. The recess 20 is continuously provided in a rectangular shape in plan view along the four sides of the rectangular plate 1. The recess 20 is formed in a rectangular cross-section and is a space surrounded by flat inner walls 20a, outer walls 20b, and upper walls 20c respectively. When forming the recess 20 by machining, on the back surface of the metal plate 1, using an end mill, a groove with a rectangular cross-section is cut along the outer circumference of the plate 1. The depth of the groove is, for example, 1 / 2 of the thickness of the plate 1, but it is not limited to this, and any depth that can ensure the strength of the plate 1 at least is acceptable. When forming by machining, on the safety surface or strength surface, it is advisable to have small rounds (roundness) at the four corners of the groove in rectangular shape in plan view. When casting the plate 1, the groove is formed using a mold. In this case, the recess 20 is formed in a trapezoid shape close to a rectangle considering the draft angle. When the plate 1 is circular, the recess 20 is a circular groove along the outer circumference of the plate 1.

[0031] And an effective cooking surface is set in the central part which is the area inside the recess 20 on the surface of the plate 1. Here, since legs 2 are provided at the four corners of the plate 1, the position of the recess 20 is inside by the mounting dimension of the legs 2 from the outer circumference of the plate 1. Here, the position of the inner wall 20a of the recess 20 is within 40 mm from the outer circumference. Therefore, the outer edge of the effective cooking surface is located within 40 mm from the outer circumference of the plate 1.

[0032] In this way, by providing the recess 20 at the end of the back surface of the plate 1, the heat conduction from the central part to the end can be effectively inhibited, the temperature of the effective cooking surface inside the recess 20 can be raised, and the temperature at the end outside the recess 20 can be lowered, so that cooking can be carried out at a high temperature on the effective cooking surface. Moreover, since no food ingredients are placed at the end of the plate 1, the recess 20 is provided as close as possible to the outer circumference of the plate 1, and the effective cooking surface can be set widely.

[0033] In the concave portion 20 having a rectangular cross section, the thickness of the plate 1 is the thinnest, and the outer surface of this thin portion is flat. Therefore, the cross section becomes wider than that of a groove having other shapes, and the distance as the heat passage becomes the longest. As a result, the heat conduction inhibition effect is maximized.

[0034] As the cooking plate 1 of the second embodiment, as shown in FIG. 3, the concave portion 20 is provided at the outer peripheral edge of the back surface of the plate 1. The concave portion 20 is formed by cutting out a rectangular shape with a predetermined width from the outer end of the back surface of the plate 1. A leg (not shown) is attached to the concave portion 20, and the plate 1 is supported at a position floating from the device main body 3. Therefore, the heat conduction to the device main body 3 is greatly inhibited. Further, since the concave portion 20 does not overlap with the range of the heat source, the heat loss to the end portion of the plate 1 is reduced accordingly. Note that other configurations are the same as those of the first embodiment.

[0035] As the cooking plate 1 of the third embodiment, as shown in FIG. 4, an outflow prevention groove 21 is formed so as to be located outside the concave portion 20 along the four sides of the surface of the plate 1. Note that other configurations are the same as those of the first embodiment. This outflow prevention groove 21 prevents the cooking juice and oil generated during cooking from flowing out to the outer periphery of the plate 1. The outflow prevention groove 21 has a rectangular cross section, and the distance between the inner wall 21a of the outflow prevention groove 21 and the outer wall 20b of the concave portion 20 is set to be about the thickness of the effective cooking surface. By providing the outflow prevention groove 21, a certain heat conduction inhibition effect can be obtained. However, by providing two grooves on the front and back, the heat passage is bent and extended in a labyrinth shape, and the heat conduction inhibition effect is enhanced.

[0036] As the cooking plate 1 of the fourth embodiment, as shown in FIG. 5, a heat insulating material 22 is accommodated in the recess 20. Note that other configurations are the same as those of the first embodiment. Since the applicable temperature of the cooking plate 1 is high, an inorganic heat insulating material 22 is suitable, and examples thereof include rock wool, perlite, and heat insulating brick materials. Although heat dissipation occurs due to convective heat transfer from the surface of the groove forming the recess 20 to the surroundings, by providing the heat insulating material 22, heat dissipation can be suppressed, the temperature drop of the effective cooking surface can be prevented, and the energy saving effect can be maximized.

[0037] As the cooking plate 1 of the fifth embodiment, as shown in FIG. 6, the plate 1 is a perforated flat plate, so-called a roaster. Note that other configurations are the same as those of the first embodiment. A plurality of slits 23 are formed in parallel with the short side on the effective cooking surface of the plate 1 and are used as openings for separating and dropping cooking juices and fats and oils. At the same time, it also serves as a passage for hot air heated by a heater or the like on the back surface, and in the case of gas heating, it also serves as part of the exhaust passage. Striped burnt marks can be formed on the food ingredients.

[0038] As the cooking plate 1 of the sixth embodiment, as shown in FIG. 7, the plate 1 is a plate for takoyaki, and a plurality of hemispherical depressions 24 are provided on the effective cooking surface. If the depression 24 is made shallow with a diameter of about 100 mm, it becomes a plate for imokawa-yaki. Note that other configurations are the same as those of the first embodiment. Also in such a plate 1, since the outside of the effective cooking surface is flat, by providing a recess 20 on the back surface, it is possible to inhibit heat conduction to the end of the plate 1 and increase the temperature of the effective cooking surface.

[0039] As the cooking plate 1 of the seventh embodiment, as shown in FIG. 8, the plate 1 is made of a wire mesh. Note that other configurations are the same as those of the first embodiment. The plate 1 is formed by combining horizontal wires 25 and vertical wires 25. By thinning the horizontal and vertical wires 25 located near the end of the plate 1 and reducing the cross-sectional area, a recess 20 is formed. For example, the wire 25 is drawn to reduce the cross-sectional area of the wire 25. The cross-section of the drawn wire 25 is usually circular, but by using a special mold, it can be made into a semi-circular cross-section or a rectangular cross-section with a flat bottom surface. Alternatively, if the position to be drawn is press-molded, the wire 25 can be made into a cross-sectional shape according to the mold, and the cross-sectional area can be reduced. By providing the recess 20 at the end of the net-like plate 1, the heat conduction to the end of the plate 1 can be inhibited.

[0040] As the cooking plate 1 of the eighth embodiment, as shown in FIG. 9, in the plate 1 of the second embodiment, a weir member 26 is provided on the outer peripheral surface thereof to prevent fats and oils or cooking juices associated with cooking from flowing back to the back surface of the plate. Note that other configurations are the same as those of the first embodiment. The weir member 26 is a thin flat plate in the shape of a tape, for example, a strip steel with a thickness of several millimeters, which is attached to the outer peripheral surface of the plate 1 by welding. The upper end of the weir member 26 is positioned higher than the effective cooking surface, the lower end is positioned at the same height as or lower than the back surface of the effective cooking surface, and lower than the upper wall of the recess 20. At the upper part of the weir member 26, it prevents fats and oils from flowing back to the back surface of the plate 1. However, if by any chance the fats and oils pass over the upper end of the weir member 26, oil drainage is performed at the lower part of the weir member 26 to let the fats and oils drip. Therefore, there is no need to set the upper end of the weir member 26 extremely high, and a height about the thickness of the effective cooking surface is sufficient.

[0041] As the cooking plate 1 of the ninth embodiment, as shown in FIG. 10, a stepped portion 27 is provided with the end portion of the plate 1 being higher than the effective cooking surface. Note that other configurations are the same as those of the first embodiment. The stepped portion 27 is formed from the outer edge of the effective cooking surface to the outer peripheral surface of the plate 1, the height of the stepped portion 27 is set to be equal to or less than the thickness of the effective cooking surface, and the inner wall 27a of the stepped portion 27 is closer to the center than the inner wall 20a of the concave portion 20. The outer edge of the effective cooking surface is at the position of the inner wall 27a of the stepped portion 27. Then, the depth of the groove forming the concave portion 20 is increased, and the thickness of the plate 1 in the concave portion 20 does not increase.

[0042] By providing such a stepped portion 27, it is possible to suppress the grease from flowing around to the back surface of the plate 1. Further, since the heat capacity increases as the thickness of the end portion of the plate 1 increases, the temperature rise of that portion can also be suppressed.

[0043] The temperature change of the plate cross-section when the thickness near the back surface end of the cooking plate 1 was reduced was confirmed using numerical calculations. The calculation was performed by solving the unsteady two-dimensional heat conduction equation (1) using the implicit difference formula (2).

Equation

Equation

[0044] Boundary conditions are exemplified in the following table. Note that the symbols are based on general notations in the heat transfer field and are generally as follows. Symbols: T; (absolute) temperature, x, y; coordinates in the horizontal and vertical (thickness) directions, t; time, α; thermal diffusivity, Qv; heat generation rate, λ; thermal conductivity, ρ; density, c; specific heat, h; heat transfer coefficient, qw; external heating amount Subscripts: i, j; position numbers in the x and y directions, k; time number, f; boundary film (temperature boundary layer), w; wall surface

Table 1

[0045] Since the calculations were two-dimensional, the calculated temperature distribution corresponds to that of the central cross-section of Plate 1 with a width of 200 mm and infinite depth (substantially more than 3 to 5 times the width). The calculations were performed with a mesh size of 1 mm for both width and thickness, and a time step of 5 seconds. Heating was calculated by applying a heat flux of 9.375 kW / m to a 100 mm-wide area on the back surface of the center of Plate 1 for a 6 mm-thick steel plate, and 18.75 kW / m for a 12 mm-thick steel plate. The heat transfer coefficient from Plate 1 to the surrounding environment was set to 0 W / m (insulated) for the unheated part of the back surface, and 20 W / m for the rest. This is because the unheated part of the back surface is near the heated part, and it was considered that the temperature inside the cooking equipment in that area would increase, resulting in no heat loss but rather heat absorption. Convergence of the calculations was determined when the temperature difference between the current and previous calculations at each position in the cross-section was less than 0.000001 °C at all grid points. 2 to a 12 mm-thick steel plate. 2 The heat transfer coefficient from Plate 1 to the surrounding environment was set to 0 W / m 2 (insulated) for the unheated part of the back surface, and 20 W / m 2 for the rest.

[0046] The five tables listed in Fig. 11 show the calculation results of the unsteady temperature distribution of the central cross-section of Plate 1 after 60 seconds (1 minute), 120 seconds (2 minutes), 180 seconds (3 minutes), 300 seconds (5 minutes), and 600 seconds (10 minutes) after heating from above. The calculation was performed using the physical property values of a mild steel plate with a width of 200 mm and a thickness of 6 mm. The numerical values in each cell are the Celsius temperatures at the position of the depth j mm from the surface of Plate 1 and the distance i mm from the left end. However, the part with a width of 30 mm and a depth of 4 mm at a distance of 10 mm from the left end corresponding to the part where the thickness is reduced (recess 20) is left blank. The calculation with the reduced thickness was performed only on the left half-plane and not on the right half-plane. Therefore, the effect of reducing the thickness becomes clear by comparing the numerical values of the cells at symmetric positions. Note that the numerical values in the 1st and 2nd columns of the table represent the depth j mm from the surface, and the numerical values in the 1st and 2nd rows represent the distance i mm from the left end. Therefore, each cell starting from the 3rd column and 3rd row of the table is the temperature of that part. Incidentally, the value at the position where j is 0 mm, that is, the depth is 0 mm, corresponds to the surface temperature of Plate 1, and the value at the position where i is 0 mm indicates the surface temperature at the left end. Similarly, the position where j is 6 mm represents the surface temperature of the back side, and the position where i is 200 mm represents the surface temperature at the right end. By comparing the temperatures at symmetric positions near the ends of Plate 1, it can be seen that the temperature is higher than the symmetric position near the center of the part where the thickness is reduced and lower than the symmetric position near the left end.

[0047] Figure 12 shows a comparison of the calculation results 300 seconds after reducing the thickness of Plate 1, while changing its size, overall thickness, adding insulation, or the material (using physical property values equivalent to SUS304). The left end of the portion where the thickness is reduced (recess 20) is 10 mm from the left end of Plate 1. 12-1 shows a material of mild steel with a thickness of 6 mm, a groove width of 20 mm, and a depth of 4 mm; 12-2 shows a material of mild steel with a thickness of 6 mm, a groove width of 30 mm, and a depth of 3 mm; 12-3 shows a material of mild steel with a thickness of 6 mm, a groove width of 30 mm, and a depth of 4 mm; 12-4 shows a material of mild steel with a thickness of 12 mm, a groove width of 30 mm, and a depth of 8 mm; 12-5 shows a material of mild steel with a thickness of 6 mm, the groove filled with insulation material, a groove width of 30 mm, and a depth of 4 mm; 12-6 shows a material of stainless steel (SUS304) with a thickness of 6 mm, a groove width of 30 mm, and a depth of 4 mm. In all cases, it can be seen that the temperature is higher than the symmetric position near the center of the portion where the thickness is reduced, and lower than the symmetric position near the left end. Thus, it can be confirmed that the four effects listed in the effects of the invention can be achieved.

[0048] Figure 13 shows the calculation results 300 seconds after reducing (notching) the back thickness of the end of the plate 1 as shown in Figure 3. 13-1 is made of mild steel, the width of the groove is 20 mm, and the depth is 6 mm. 13-2 is the same as 13-1 except that only the width of the groove is changed to 30 mm. 13-3 is the same as 13-2 except that heat insulation is applied to the groove. 13-4 is the same as 13-2 except that only the material is changed to stainless steel (SUS304). It can be seen that in any of the notch size, heat insulation, or material change at the end, the temperature is higher than that at the symmetric position above or closer to the center of the reduced-thickness part. In this case, it can be seen that among the effects listed in the effects of the invention, the effect of improving the cooking function is realized. Furthermore, in the part where the thickness is reduced by notching, legs 2 are usually provided with bolts or the like to restore the height. Therefore, heat can be prevented from escaping (diffusing / dissipating) from the end of the plate 1 through the legs 2 to the surroundings. Thus, an energy-saving effect can be achieved by reducing the amount of heat added. In addition, by providing a part with a reduced thickness at the end of the plate 1 and using the legs 2, it is possible to easily conform to the temperature regulation of the contacting member (usually the housing), or to expect an effect of converting the contacting member or the secondary contacting member to a low heat-resistant material.

[0049] Note that the present invention is not limited to the above-described embodiments, and it goes without saying that many modifications and changes can be made to the above-described embodiments within the scope of the present invention. In the heating and cooking plate 1, in a roaster or a Genghis Khan grill, grooves for separating and storing cooking juices and fats on the surface are often provided. The grooves can be provided on the outside (end side) or inside (central part side) of the surface portion corresponding to the recess 20 on the back surface. In particular, when provided on the outside, the evaporation of cooking juices and fats in the surface grooves is suppressed by the heat transfer inhibition effect of the recess 20 on the back surface. Conversely, when provided on the inside, evaporation is promoted. Which is appropriate can be determined according to the cooking purpose and the labor of cleaning.

[0050] To form a groove for the recess 20 at the end of the plate 1, casting is simple and inexpensive. In particular, for so-called lost tops with a large number of long holes provided on the cooking surface, or plates 1 such as takoyaki plates or Genghis Khan pans with openings or unevenness on the cooking surface, it is reasonable to mold them together by casting. As casting methods, not only general sand casting (ordinary casting), but also investment casting used for more precise shaping and die casting used for low melting point metals such as aluminum can be used.

[0051] For forming the recess 20 of the plate 1 whose effective cooking surface is flat, machining with an end mill is appropriate. At the same time, if machining is also performed on the part that appears on the surface, a high-class finish can be obtained.

[0052] Since the plate 1 is generally formed to be relatively thick (4 mm or more) as a whole, hot forging is appropriate when manufacturing by forging. The plate 1 heat-treated appropriately after forming has the feature of less thermal deformation (warping and twisting) during heating in cooking.

Explanation of Signs

[0053] 1 Plate 2 Leg 3 Equipment main body 20 Recess 21 Anti-drainage groove 22 Heat insulation material 23 Slit 24 Depression 25 Wire 26 Weir member 27 Step portion

Claims

1. In a cooking plate for a cooking appliance that places food on the surface of the plate and performs cooking by heating from the back or inside of the plate, a recess with a rectangular cross-section and a reduced thickness is provided at the end of the back surface of the plate. An effective cooking surface capable of cooking at a high temperature is set on the surface of the plate inside the inner wall of the recess. A groove is provided on the surface of the plate outside the recess to store the cooking juice and oil generated during cooking so as not to flow out to the outer periphery of the plate. The recess inhibits heat conduction from the effective cooking surface to the outside. A cooking plate for cooking, characterized in that.

2. In a cooking plate for a cooking appliance that places food on the surface of the plate and performs cooking by heating from the back or inside of the plate, a recess with a rectangular cross-section and a reduced thickness is provided at the end of the back surface of the plate. An effective cooking surface capable of cooking at a high temperature is set on the surface of the plate inside the recess. A stepped portion higher than the effective cooking surface is formed from the outer edge of the effective cooking surface to the outer peripheral surface of the plate so as to prevent the cooking juice and oil generated during cooking from flowing into the back surface of the plate at the end of the surface of the plate. The inner wall of the stepped portion that forms the outer edge of the effective cooking surface is closer to the center than the inner wall of the recess. The recess inhibits heat conduction from the effective cooking surface to the outside. A cooking plate for cooking, characterized in that.

3. The cooking plate for cooking according to claim 1 or 2, characterized in that legs are provided outside the recess on the back surface of the plate.

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