JPH06168777A - Top plate for induction heater - Google Patents

Abstract

PURPOSE:To improve safety for handling and conveniences for use. CONSTITUTION:A heating coil 2 is laid on an inverter device 1, and a top plate 8 becoming luminous upon exposure to heat, is horizontally supported above the coil 2. The lower side of the top plate 8 is fitted with an optical fiber voltage sensor 9. An optical fiber 11 is laid along a route from the sensor 9 to the top plate 8, and the end of the fiber 11 is inserted in space within the top plate 8. In addition, a plurality of the end sections 12 of the fiber 11 are exposed on the upper surface of the top plate 8. In this case, the end sections 12 are laid to ensure good visibility, for example, in an annular configuration. The sensor 9 is connected to the power supply section of the device 1 via a cord 13, and power voltage, when applied to the device 1, is also applied to the sensor 9. The sensor 9, upon exposure to the voltage, emits an optical signal showing a progress of operation, and sends the signal to the top plate 8 through the optical fiber 11, thereby emitting the signal upward from the end sections 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a top plate used in an induction heater such as an electromagnetic cooker.

[0002]

2. Description of the Related Art Generally, an induction heater such as an electromagnetic cooker places an object to be heated on a top plate supported on a heating coil and heats the object to be heated by induction heating. Figure 8
FIG. 4 is an explanatory diagram showing a usage state of the induction heater. As shown in the figure, in the induction heater, the heating coil 2 is installed on the inverter device 1, and the top plate 3 is horizontally supported above the heating coil 2. Furthermore, the object 4 to be heated is heated by turning on the inverter device 1 with the object 4 to be heated placed on the upper surface of the top plate 3. Figure 9
It is a perspective view of the top plate 3. Ceramics are generally used for the top plate 3. The induction heater is heated by operating the power switch.

[0003]

In the induction heater, when the heating coil 2 is energized to heat the object 4 to be heated, the top plate 3 is heated by the radiant heat from the object 4 to be heated. It gets hot. However, even if the top plate 3 becomes hot, there is no change in its appearance. Therefore, there is a risk that the top plate 3 will not be hot during heating and may be accidentally touched and burned.

Further, it cannot be judged from the appearance of the top plate 3 that the heating coil 2 of the induction heater is energized, that is, is being heated. Must be done, and the operability is poor. In addition, there is a problem that it is easy to forget to turn off the power after heating. The present invention has been made to solve the above problems, and the purpose thereof is to facilitate the confirmation of the heating state of the top plate and the energization state of the heating coil, and the safety of the induction heater, An object is to provide a top plate for an induction heater that can be easily used.

[0005]

In order to achieve the above object, a first invention is a top plate for an induction heater, which is disposed above a heating coil driven by an inverter device and supports an object to be heated, It is characterized by being formed by using a material whose surface is discolored at high temperature.

Here, it is preferable to apply a heat-sensitive dye that develops color at high temperature to the surface of the top plate for the induction heater. It is also possible to mix and form a heat-sensitive dye that develops color at high temperatures in the constituent material of the induction heater top plate.

According to a second invention, in the first invention, the operation signal output means for outputting the operation state of the heating coil as an optical signal, the operation signal output means and the top plate are connected, and the top plate is connected. And an optical fiber which is arranged so as to form a pattern on the surface and emits the optical signal output from the operation signal output means from the top plate surface.

Here, as the operation signal output means, a voltage sensor for transmitting the incident light from the light source when detecting that a power supply voltage is applied, or a light source for detecting a magnetic field generated from the heating coil during heating standby is output from the light source. It is preferable to use a voltage sensor that transmits incident light.

[0009]

In the first aspect of the invention, the top plate for the induction heater arranged above the heating coil driven by the inverter device is being heated because it is made of a material whose surface discolors at high temperatures. This is visually confirmed by the discoloration of the surface. The top plate is formed by coating a surface with a heat-sensitive dye that develops color at high temperature, or by mixing a heat-sensitive dye that develops color at high temperature in a constituent material.

In the second invention, the operating state of the heating coil is output as an optical signal from the operating signal output means and sent to the top plate via the optical fiber. The sent light is emitted to the outside from an optical fiber arranged so as to form a pattern on the surface of the top plate. If a voltage sensor that transmits the incident light from the light source when it detects that a power supply voltage is applied is used as the operation signal output means, the fact that the power is turned on is visually recognized by the patterned light emission on the surface of the top plate. Can be confirmed.

Further, if a voltage sensor that transmits the incident light from the light source when the magnetic field generated from the heating coil is detected during the heating standby is used as the operation signal output means, the fact that the heating standby is in progress is indicated on the top plate surface. It can be visually confirmed by the patterned light emission.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a first embodiment of the first invention. This example shows a top plate 3 for an induction heater.
Apply a heat-sensitive dye that develops color at high temperature to the surface of pattern 5
Is formed.

When an object to be heated is heated using this top plate 3, when the temperature of the top plate 3 rises due to the radiation from the object to be heated and reaches the reaction point of the heat-sensitive dye, heat The pattern 5 made of a pigment develops color.
Since the coloring of the pattern 5 makes it possible to visually confirm that the top plate 3 is heated, it is less likely that the top plate 3 is accidentally touched and burned during heating.

FIG. 2 is a perspective view showing a second embodiment of the first invention. In this embodiment, when the top plate 6 for an induction heater is molded, a heat-sensitive dye 7 that develops color at high temperature is mixed in its constituent material. When an object to be heated is heated using this top plate 6, when the temperature of the top plate 6 rises and reaches the reaction point of the heat-sensitive dye 7, the heat-sensitive dye 7 develops color and the surface of the top plate 6 also differs. Changes to a different color.

As described above, the coloring of the heat-sensitive dye 7 makes it possible to visually confirm that the top plate 6 is heated. Therefore, it is less likely that the top plate 6 is erroneously touched and burned during heating. Become.

FIG. 3 is a side view showing a third embodiment according to the second invention, FIG. 4 is an enlarged perspective view of the top plate 8 in FIG. 3, and FIG. 6 is a block diagram illustrating an operation of the optical fiber voltage sensor 9 in FIG.

In FIG. 3, reference numeral 1 is an inverter device on which a heating coil 2 is installed. Further, a top plate 8 is horizontally supported above it.
An optical fiber voltage sensor 9 is arranged on the lower surface of the top plate 8. An optical fiber 11 is connected to the sensor 9 and is laid down to the top plate 8, and
The optical fiber 11 is inserted into the inside of the top plate 8, and a plurality of ends 12 are opened on the surface of the top plate 8 as shown in FIG. The end portion 12 is arranged, for example, in an annular shape so that it can be easily seen.

The sensor 9 is connected to the power source section of the inverter device 1 by the cord 13, and when the power source voltage is applied to the inverter device 1, the voltage is also applied to the sensor 9. When a voltage is applied, the sensor 9 emits an optical signal indicating that it is operating and sends it to the top plate 8 via the optical fiber 11.

The top plate 8 emits the transmitted optical signal from the end 12 upward. That is, when the power of the inverter device 1 is turned on and the inverter device 1 is in the operating state, the end 12 of the optical fiber 11 arranged on the surface of the top plate 8 emits light, and the induction heater is turned on. Can be visually confirmed.

Next, the operation of the optical fiber voltage sensor 9 will be described with reference to FIG. The light source 14 includes a lamp that is turned on by a power source common to the inverter device 1, and the optical fiber 1
The sensor 9 is illuminated via 5. The sensor 9 transmits the incident light only when a voltage is applied from the cord 13 and emits it to the optical fiber 11. The top plate 8 has the same structure as the top plates 3 and 6 in the first and second embodiments and is heated to
Color develops when the plate 8 becomes hot.

As a result, in this embodiment, the fact that the top plate 8 itself has become hot can be visually recognized by the discoloration of the surface of the top plate 8 and whether the inverter device is turned on or not is indicated on the surface of the top plate 8. It can be visually recognized by the light emission of the end 12 of the opened optical fiber 11.
Therefore, it is possible to prevent forgetting to turn off the power and improve the usability of the electromagnetic cooker.

In the third embodiment, it is also possible to send the light emitted from the light source 14 directly to the top plate 8 without passing through the sensor 9. In that case, while the power of the inverter device 1 is on. Emits light on the surface of the top plate 8.

FIG. 6 is a side view showing a fourth embodiment according to the second invention, and FIG. 7 is a block diagram for explaining the operation of the optical fiber magnetic field sensor 16 in FIG. In this embodiment, the optical fiber voltage sensor 9 in the third embodiment is replaced with an optical fiber magnetic field sensor 16, and other common parts are designated by the same reference numerals and the description thereof will be omitted.

The sensor 16 is fixed to the top plate 8 above the end portion of the heating coil 2, detects a small magnetic field generated while the inverter device 1 is in the heating standby state, and the magnetic field is generated. Optical signal is sent to the optical fiber 11 only while
To go out. Next, the operation of the optical fiber magnetic field sensor 16 will be described with reference to FIG. The light emitted from the light source 14 is the optical fiber 1.
The sensor 16 is illuminated via 5. If a magnetic field is generated in the inverter device 1, the sensor 16 transmits the incident light and emits it to the optical fiber 11.

This embodiment also has the same effect as that of the third embodiment, but has the feature that the fact that the inverter unit 1 is in the standby state for heating can be visually recognized from the upper surface of the top plate 8. Further, by combining these third and fourth embodiments, it is possible to display the lights respectively sent from the optical fiber voltage sensor 9 and the optical fiber magnetic field sensor 16 in different colors on the same top plate. In that case, it is possible to easily identify whether the power is on or the heating standby state.

[0026]

As described above, according to the first invention,
Since the top plate for the induction heater is made of a material whose surface discolors at a high temperature, when the top plate becomes hot, it can be visually confirmed by the discoloration of the surface. Thereby, it is possible to prevent accidental touching and burn.

According to the second aspect of the invention, an optical signal indicating the operating state of the heating coil is sent to the top plate via the optical fiber and is emitted in a pattern from the surface of the top plate to the outside. As a result, the operation state can be visually confirmed, so that it is less likely to forget to turn off the power and the usability is improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing a first embodiment according to the first invention.

FIG. 2 is a perspective view showing a second embodiment according to the first invention.

FIG. 3 is a side view showing a third embodiment according to the second invention.

FIG. 4 is an enlarged perspective view of the top plate shown in FIG.

5 is a block diagram illustrating an operation of the optical fiber voltage sensor in FIG.

FIG. 6 is a side view showing a fourth embodiment according to the second invention.

7 is a block diagram illustrating an operation of the optical fiber magnetic field sensor in FIG.

FIG. 8 is an explanatory diagram showing a usage state of the induction heater.

FIG. 9 is a perspective view showing a conventional example.

[Explanation of symbols]

 1 Inverter device 2 Heating coil 3 Top plate 5 Pattern 6 Top plate 7 Thermal dye 8 Top plate 9 Optical fiber voltage sensor 11 Optical fiber 12 End part 13 Code 14 Light source 15 Optical fiber 16 Optical fiber magnetic field sensor

Claims (6)

[Claims] 1. An induction heater top plate, which is disposed above a heating coil driven by an inverter device and supports an object to be heated, formed by using a material whose surface discolors at high temperature. Top plate for heater. 2. The top plate for an induction heater according to claim 1, wherein the surface is coated with a heat-sensitive dye that develops color at high temperatures. 3. The top plate for an induction heater according to claim 1, wherein the thermosensitive dye that develops color at a high temperature is mixed in a constituent material. 4. The induction heater top plate according to claim 1, wherein the operation signal output means for outputting the operation state of the heating coil as an optical signal, and the operation signal output means and the top plate are connected together. An optical fiber, which is arranged so as to form a pattern on the surface of the top plate, and which emits the optical signal output from the operation signal output means from the surface of the top plate. plate. 5. The induction heater top plate according to claim 4, wherein the operation signal output means is constituted by a voltage sensor that transmits incident light from the light source when it detects that a power supply voltage is applied. ·plate. 6. The induction heater top plate according to claim 4, wherein the operation signal output means is constituted by a voltage sensor that transmits incident light from the light source when a magnetic field generated from the heating coil is detected during heating standby. Top plate for heater.