JP5409139B2 - Induction heating cooker - Google Patents

Description

  The present invention relates to an induction heating cooker that induction-heats a cooking container.

  The surface of the top plate of a conventional induction heating cooker has a very small thickness of about 0.1 mm to prevent the cooking container from slipping and sticking due to a water film that has entered the gap between the top plate surface and the bottom surface of the cooking container. A dot pattern is printed. Therefore, the gap between the top plate surface and the bottom surface of the cooking container is never completely zero.

  On the other hand, unlike conventional aluminum cooking containers, conventional cooking containers for induction heating cookers have a flat bottom surface. For this reason, there is no rattling when it puts on the top plate of an induction heating cooking appliance. In addition, the distance between the bottom surface of the cooking container and the heating coil under the top plate is equal, and the thermal efficiency is good. On the other hand, the heat of the cooking container induction-heated by the heating coil under the top plate is conducted to the top plate, and the temperature of the top plate surface rises. Therefore, for example, in Patent Document 1, a protrusion is provided on the top plate, and the cooking container is floated from the top plate surface to reduce the contact area, thereby suppressing heat conduction from the cooking container to the top plate surface to prevent temperature rise. Yes.

Japanese Patent Laid-Open No. 2005-32660

  The conventional induction heating cooker has a slight gap between the bottom surface of the cooking container due to the dot pattern formed on the top plate surface. FIG. 11 is a cross-sectional view of the top plate 11 and the cooking container 20 of a conventional induction heating cooker. In FIG. 11, the gap 30 between the top plate 11 and the bottom surface 21 of the cooking container 20 created by a dot pattern (not shown) is liable to cause a capillary phenomenon. Moisture 40 is easily sucked into the entire bottom surface 21 by capillary action. In addition, since the amount of moisture 40 sucked is very small, the time to evaporate is short, and there is a problem that a wide range of scorch occurs in a short time.

  FIG. 12 is a cross-sectional view of the top plate 11 and the cooking container 20 of the induction heating cooker disclosed in Patent Document 1. As shown in FIG. 12, projections 50 are provided on the top plate 11 at certain intervals. In the case of this configuration, there is a problem that the moisture 40 spilled through between the protrusions 50 permeates over a wide range. Moreover, when the prominent protrusion 50 is provided on the surface of the top plate as in Patent Document 1, there is a possibility that the cooking container 20 may be hooked on the protrusion and fall down, which is not practical. Furthermore, the protrusion 50 may be damaged and worn while repeatedly contacting the cooking container 20.

  The present invention has been made to solve the above-described problems, and prevents the occurrence of capillary action between the top plate surface and the bottom surface of the cooking container to prevent the spread of spilled moisture and the temperature of the top plate. The purpose is to prevent scorching by suppressing the rise.

Concentric induction heating cooker according to the present invention, the surface of the top plate, have a gentle irregular shape in which a plurality of recesses is formed by forming, uneven shape, centered on the position corresponding to the center position of the heating coil The width in the radial direction of the recess at the position corresponding to the outer peripheral side of the heating coil is larger than the radial width of the recess in the position corresponding to the center side of the heating coil and larger than the diameter of the heating coil. And a groove extending from the center side of the heating coil toward the outer peripheral side, and the top of the protrusion is the same height as the surface of the top plate .

  According to the present invention, since the surface of the top plate is provided with a gentle uneven shape formed with a plurality of recesses, it is difficult to cause capillary action between the top plate surface and the bottom surface of the cooking container, and the top plate is blown out from the cooking container. In addition to preventing the spread of moisture, the temperature rise of the top plate can be suppressed to prevent the spilled moisture from being burnt.

It is a top view which shows the structure of the induction heating cooking appliance which concerns on Embodiment 1 of this invention. It is sectional drawing which cut | disconnected the induction heating cooking appliance and cooking container shown in FIG. 1 along the AA line. FIG. 3A is a cross-sectional view showing a concavo-convex shape on the top plate surface, FIG. 3A is a wavy concavo-convex cross section of Embodiment 1, FIG. 3B is a trapezoidal concavo-convex cross section, and FIG. Show. It is a top view which shows another structural example of the recessed part of the top plate surface. It is sectional drawing which cut | disconnected the induction heating cooking appliance shown in FIG. 4 along the BB line. It is a top view which shows another structural example of the recessed part of the top plate surface. It is a top view which shows another structural example of the recessed part of the top plate surface. It is a top view which shows another structural example of the recessed part of the top plate surface. It is a top view which shows another structural example of the recessed part of the top plate surface. It is sectional drawing which cut | disconnected the induction heating cooking appliance shown in FIG. 9 along CC line. It is sectional drawing of the top plate and cooking container of the conventional induction heating cooking appliance. It is sectional drawing of the top plate and cooking vessel of the induction heating cooking appliance disclosed by patent document 1. FIG.

Embodiment 1 FIG.
FIG. 1 is a plan view showing a configuration of induction heating cooker 10 according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view of the induction heating cooker 10 and the cooking container 20 shown in FIG. 1 cut along the line AA. In the following description of the embodiment, the same or equivalent components as those of the prior art (FIGS. 11 and 12) described above are denoted by the same reference numerals. The top plate 11 of the induction heating cooker 10 is made of, for example, crystallized glass, and a heating coil 12 indicated by a broken line is provided below the top plate 11. A concentric recess 13 is formed on the surface of the top plate 11 corresponding to each position of the heating coil 12. Moreover, in FIG. 1, the cooking container 20 is shown with a dashed-two dotted line as an example of cooking containers, such as a pan used for cooking, a frying pan.

  As shown in FIG. 2, when the surface of the top plate 11 is a reference surface 14, a plurality of shallow recesses 13 of about 0.3 to 0.5 mm are provided in the reference surface 14. By providing the concave portion 13 continuously formed in a wave shape, the reference surface 14 between the concave portion 13 and the concave portion 13 becomes the convex portion 15. Therefore, the reference surface 14 and the top of the convex portion 15 are at the same height position. The top of the convex portion 15 becomes a surface that directly contacts the bottom surface 21 when the cooking container 20 is placed on the top plate 11.

In the case of the concavo-convex shape shown in FIG. 2, the moisture 40 spilled from the cooking container 20 stays in the concave portion 13 and enters the convex portion 15 a located at the peripheral edge of the bottom surface 21 by capillary action. However, since the gap 30 is widened by the presence of the next concave portion 13 on the center side from the convex portion 15a, the capillary phenomenon does not occur, and the water does not advance toward the central side from the convex portion 15a. In this way, the concave portion 13 is subdivided by the convex portions 15 and 15a to prevent water from spreading over a wide area.
If the bottom of the concave portion 13 is shallow with respect to the reference surface 14 (and the top of the convex portion 15), the capillary phenomenon cannot be sufficiently cut off and the water may be flooded over a wide area, so that reliable flood prevention is possible. In order to obtain the effect, it is desirable to form the recess 13 with a depth of about 1.0 mm or more. Furthermore, considering the strength and cleanability of the top plate 11, the depth of the recess 13 is desirably about 2.0 mm or less. The strength and cleanability will be described later.

  Further, since the concave portion 13 faces the bottom surface 21 with the air layer of the gap 30 interposed therebetween, the thermal conductivity is lower than that of the convex portion 15 that directly contacts the bottom surface 21. Therefore, the transmission of the amount of heat radiated from the cooking container 20 to the top plate 11 surface can be suppressed. Therefore, the surface temperature of the top plate 11 can be kept low by providing a large number of the recesses 13 or increasing the area of the recesses 13 to reduce the contact area between the cooking container 20 and the top plate 11. If the temperature of the top plate 11 is low, even if the moisture 40 spilled from the cooking container 20 adheres to the top plate 11, it will not burn or it will take longer to burn, so there is a possibility of burning. Can be reduced. It also increases the effect of preventing burns.

Further, if the moisture 40 does not diffuse over the entire bottom surface 21 and stays in a narrow range, the contact area between the moisture 40 and the bottom surface 21 is small and the amount of heat received is small, so the heating rate of the moisture 40 is slowed down, The time until burn-in is longer and the possibility of burn-in is reduced.
Further, as a result of reducing the contact area between the top plate 11 and the cooking vessel 20, the amount of heat received by the top plate 11 from the bottom surface 21 of the cooking vessel 20 can be suppressed, so that heat loss is small and cooking can be performed with more energy saving. It becomes possible.

FIG. 3 is a cross-sectional view showing the concavo-convex shape on the surface of the top plate 11, and FIG. 3A shows the wavy concavo-convex cross section of the first embodiment. FIG. 3B shows a trapezoidal uneven cross-section, and FIG. 3C shows an arc-shaped uneven cross-section as in Patent Document 1. As shown in FIG. 3A, the top plate 11 of the present embodiment has a gentle wavy uneven shape, and the height difference between the concave portion 13 and the convex portion 15 is reduced, so that cleaning is easy and dirt is accumulated. Hateful. The dirt can be easily wiped by wiping in the direction along the shape of the recess 13 so as to draw a circle if the concentric recess 13 as shown in FIG. Therefore, even if a scoring occurs, the scoring range is narrow and can be easily removed due to the gentle uneven shape because the water is not submerged from the vicinity of the periphery of the bottom surface 21 of the cooking container 20 as described above.
On the other hand, in the case of the trapezoidal unevenness shown in FIG. 3B, the unevenness switching portion becomes a corner and the dirt 60 tends to accumulate. Also, for example, as shown in FIG. 3C, even when a convex / convex portion is formed by forming a curved convex portion on a flat surface, the dirt 60 tends to accumulate in the concave / convex switching portion.

Further, as shown in FIG. 3A, the robustness of the top plate 11 is ensured by making the concavo-convex shape a structure in which gentle curved surfaces are continuously repeated so as not to concentrate stress locally. The entire structure is connected by a gentle curved surface to distribute stress and minimize the risk of breakage. Even if the cooking container 20 is moved in parallel while being placed on the top plate 11, the top of the convex portion 15 and the reference surface 14 are at the same height, so that there is no catch and safety and the placement is stable. Further, since the unevenness of the surface of the top plate 11 is very shallow, even if the cooking container 20 having a concave shape or a convex shape is used, the bottom surface 21 is not a perfect flat surface, and it is safe to move without being caught. Is also stable.
On the other hand, as shown in FIG. 3C, when the concave portion and the convex portion are not connected by a smooth continuous surface, that is, when the curvature is reduced, the top stress of the curved surface is more easily applied, which may cause damage. Moreover, since the convex part protrudes in some places from a plane part, when parallelly moving the cooking container 20 mounted on the top plate 11, there is a possibility of being caught by the convex part. Easily damaged and worn by contact.

  Next, a configuration example of the recess 13 on the surface of the top plate 11 will be described. As shown in FIG. 1, when the concavo-convex shape composed of a plurality of concave portions 13 is formed in a concentric shape having substantially the same area as the heating coil 12, the concentric circle center of each concave portion 13 coincides with the center of the heating coil 12. The user can intuitively recognize the installation center position of the cooking container 20 (that is, the heating coil position). If the concavo-convex shape is a concentric circle, it is easy for a visually handicapped person to know the center position of the installation by touch. In the case of a concentric circle shape, the radial widths of the concave portions 13 and the convex portions 15 may be the same or different.

FIG. 4 is another configuration example of the recess 13 on the surface of the top plate 11, and FIG. 5 shows a cross-sectional view taken along the line BB. In the configuration example of FIGS. 4 and 5, the recess 13 is formed concentrically as in FIG. 1. However, the recess 13 a having a diameter larger than the diameter of the heating coil 12 and having a wide radial width is formed to have a large capacity. Moisture 40 spilled from the cooking container 20 is retained in a large-capacity retaining part outside the cooking container 20 as a retaining part. Thereby, it becomes difficult for the water | moisture content 40 to penetrate | invade into the clearance gap 30 of the bottom face 21, and the amount of water immersion can be reduced.
The heating coil 12 provided under the top plate 11 is generally about 150 mm to 220 mm in diameter. On the other hand, the cooking container 20 has various sizes, and the diameter of the bottom surface 21 may exceed 300 mm for a large one. Even when a cooking container 20 having a large diameter is used, a recess 13a as a staying part for receiving the spilled moisture 40 is formed on the outside of the cooking container 20 by performing uneven processing on a larger area in a range exceeding that. Therefore, it is possible to prevent the spilled water 40 from entering the bottom surface 21. Moreover, since the recessed part 13a is located outside the heating coil 12, it is difficult to reach a high temperature. For example, even if the spilled water 40 stays in the recessed part 13a, it is difficult to burn.

FIGS. 6, 7, and 8 are other configuration examples of the recess 13 on the surface of the top plate 11. In FIG. 6, the linear recessed part 13 is continuously provided and the unevenness | corrugation is formed in stripes. The direction of the striped pattern is arbitrary. For example, the linear recess 13 may be inclined with respect to the longitudinal direction of the top plate 11 as shown in FIG. When unevenness is formed on the entire top plate 11 as shown in FIG. 6 or FIG. 7, a heating coil position display means 16 may be added to the top plate 11 in order to clearly indicate the position of the heating coil 12. The heating coil position display means 16 may be a print display indicating the position of the heating coil 12 or may be light emitted during energization of the heating coil 12, and may be provided as appropriate. On the other hand, as shown in FIG. 8, the recess 13 may be formed only on the surface of the top plate 11 at a position corresponding to the heating coil 12.
In addition, if the top plate 11 is formed with the linear recess 13 as shown in FIGS. 6, 7, and 8, the dirt is less likely to accumulate as in the concentric uneven shape, and follows the shape of the recess 13. The dirt can be easily wiped off.

FIG. 9 is a plan view showing another configuration example of the recess 13 on the surface of the top plate 11, and FIG. 10 shows a cross-sectional view taken along the CC line. In the case of the concavo-convex shape provided concentrically, among the portions covered with the bottom surface 21 of the cooking vessel 20, the gap 31 of the recess 13 near the center tends to be the highest temperature. Therefore, the air in the gap 31 near the center tends to expand.
If the air in the gap 31 expands in a state in which the periphery of the gap 31 is blocked by the moisture 40 blown from the cooking container 20, the cooking container 20 may float. Therefore, in order to allow high-temperature air near the center to escape to the outside in the concavity and convexity formed concentrically, at least one air vent groove 17 that radiates radially from the center to the outer peripheral direction may be provided.

  The material of the top plate 11 is not limited to the mainstream crystallized glass, but may be a heat resistant resin, a ceramic material, or the like. When crystallized glass is used, the concave portion 13 may be provided in the top plate 11 when press-molding a glass material melted at a high temperature. In addition, when using a methacrylic resin reinforced inorganic material generally called artificial marble or a ceramic material mainly composed of alumina or silicon nitride, the recess 13 may be integrally formed on the top plate 11 when molding. . Since the methacrylic resin reinforced inorganic material or ceramic material has a higher degree of molding freedom than crystallized glass and can form the recess 13 without significant cost increase, it forms an uneven shape as in this embodiment. It becomes a powerful material for the top plate 11.

  In the conventional flat top plate, the dot pattern printing is indispensable for preventing the water slip of the cooking container 20. However, since the water slip can be prevented by providing the uneven shape according to the present embodiment, the dot pattern Printing can be omitted. Conventionally, in addition to the top plate molding process, a total of three processes, a dot pattern printing process and a printing quenching process, were required. In this embodiment, the dot pattern printing process and the printing quenching process can be omitted by omitting the dot pattern. Thus, cost reduction can be achieved. However, the top plate 11 of the present embodiment may have a dot pattern.

  As described above, according to the first embodiment, the surface of the top plate 11 is configured to have a concentric or striped gentle uneven shape formed with a plurality of recesses 13. For this reason, the capillary phenomenon of the gap 30 between the surface of the top plate 11 and the bottom surface 21 of the cooking container 20 hardly occurs, and the spread of the moisture 40 spilled from the cooking container 20 can be prevented. Moreover, since the contact area of the top plate 11 and the cooking container 20 reduces, the temperature rise of the top plate 11 is suppressed and the burning of the spilled moisture 40 can be prevented.

  Further, according to the first embodiment, since the uneven shape is gentle and the top of the convex portion 15 has the same height as the reference surface 14, the cooking container 20 can be moved while sliding on the top plate 11. Safety can be improved without being caught in the uneven shape. Further, by providing the uneven shape, it is possible to prevent the cooking container 20 from slipping and sticking due to the water film. Therefore, the dot pattern printing and quenching step can be omitted, and the cost can be reduced.

Further, according to the first embodiment, the center position of the heating coil 12 under the top plate 11 is intuitively determined by making the uneven shape concentric with the position corresponding to the center position of the heating coil 12 as the center. Can be recognized.
Furthermore, by forming the uneven shape in a region corresponding to the heating coil 12 on the surface of the top plate, the position of the heating coil 12 can be intuitively recognized regardless of a concentric or striped shape.

Further, according to the first embodiment, when the concentric uneven shape is formed, the radial width of the concave portion 13a located at the position corresponding to the outer peripheral side of the heating coil 12 is widened, whereby the spilled moisture 40 A retention part can be made into a large capacity | capacitance and the penetration | invasion to the clearance gap 30 between the bottom face 21 of the cooking vessel 20 and the surface of the top plate 11 can be reduced.
Further, by providing the recess 13a having a diameter larger than the diameter of the heating coil 12, even if the cooking container 20 having a diameter exceeding the diameter of the heating coil 12 is used, the spilled water 40 stays in the recess 13a to cause intrusion. Can be reduced. Moreover, since the recessed part 13a is located outside the heating coil and the cooking container 20, it is difficult to reach a high temperature. For example, even if moisture 40 stays in the recessed part 13a, it is difficult to burn.

  Further, according to the first embodiment, when the concentric uneven shape is provided, by providing the groove 17 from the center side of the heating coil 12 toward the outer peripheral side, the high-temperature air near the center of the concentric circle can be released to the outside. it can.

  Moreover, according to Embodiment 1, crystallized glass, heat resistant resin, or ceramics can be used as the material of the top plate, and it can be easily molded by using especially heat resistant resin or ceramics.

  DESCRIPTION OF SYMBOLS 10 Induction cooking device, 11 Top plate, 12 Heating coil, 13, 13a Concave part, 14 Reference surface, 15, 15a Convex part, 16 Heating coil position display means, 17 Groove, 20 Cooking container, 21 Bottom surface, 30, 31 Crevice , 40 moisture, 50 protrusions, 60 dirt.

Claims (2)

In an induction heating cooker having a top plate on the upper surface of the heating coil,
Said top plate, possess on the surface, a gentle irregular shape in which a plurality of recesses formed thereon,
The concavo-convex shape is a concentric circle centered on a position corresponding to the center position of the heating coil, and the radial width of the recess at a position corresponding to the outer peripheral side of the heating coil is the center side of the heating coil. A recess having a diameter wider than the diameter of the recess at a position corresponding to the diameter of the heating coil and having a diameter larger than the diameter of the heating coil, having a groove from the center side to the outer peripheral side of the heating coil, and the top of the projection is An induction heating cooker having the same height as the surface of the top plate . The top plate of the material, the induction heating cooker of claim 1 Symbol mounting characterized in that it is a crystallized glass, heat-resistant resin, or ceramics.

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