Background Art With the rapid development of the electronic industry, products including cooking equipment such as a rice cooker as well as simple kitchenware such as a fry pan and a mug cup to which electronic devices are mounted have been being placed on the market.

The electronic devices attached to the cooking equipment or kitchenware include those related to original functions of the equipment such as cooking temperature control, and those related to special functions such as generation of a melody for celebrating a special anniversary.

As an example of simple kitchenware to which an electronic device related to a special function is attached, the structure of a melody or musical mug cup shown in Fig.

1 a will be described below.

A cup body 11 made of ceramic has essentially a concave space formed at a lower end thereof. Then, a melody generation kit (hereinafter, referred to as a"melody kit) 12 is inserted into the space that in turn is closed by an additional cover plate 13.

The cover plate 13 is made of a transparent or translucent synthetic resin with a proper strength and generally subjected to special surface processing such that a user can feel the cover plate to be homogeneous with the ceramic cup body 11.

Referring to Fig. lb that is a plan view separately showing the melody kit 12, the melody kit 12 comprises a circuit board 12a for electrically connecting respective

components arranged thereon to one another, a memory chip 12b mounted on the circuit board 12a, a battery 12c for supplying electric power to the entire melody kit 12, a thin film speaker 12d disposed at a side of the circuit board 12a, and an optical sensor S for sensing external light and simultaneously establishing a closed circuit.

The optical sensor S described herein is a sensor with a switch function among optical sensor operating mechanisms that can be classified into several types, in other <BR> <BR> words, the function of performing control (i. e. , opening or closing) of an electrical circuit including itself while sensing external light.

Whether an optical sensor has which one of the operating mechanisms, i. e. opening or closing of an electrical circuit, is a design factor for the sensor. Optical sensors placed on the market have predetermined unique uses according to their types such as a circuit opening type and a circuit closing type.

Such a circuit control type optical sensor with a switch function has been widely used in various kinds of automatic equipment including an unattended light capable of sensing whether the surroundings are bright or dark and turning on or off the light according to the sensed results.

For reference, the optical sensor for use in the unattended light corresponds to the circuit opening type described above. At night with no light introduced into the sensor, the optical sensor cannot sense light and thus the electrical circuit is not opened, whereby the unattended light remains in an"on"state. On the contrary, after morning where the surroundings get bright, the sensor senses introduction of natural light thereinto and opens the electrical circuit, thereby turning off the unattended light.

The melody mug cup 10 constructed as above is characterized in that a lilting melody is output from the melody kit 12 under particular conditions.

For example, when the mug cup 10 is simply placed on a table, the surface of the table shuts off light incident on the optical sensor S, so that there is no closing of the electrical circuit by the optical sensor S and thus a melody is not generated. On the contrary, when a user picks up the mug cup, the light shutting state by the surface of the table is released and light is incident on the optical sensor S, so that the optical sensor S closes the electrical circuit and a melody is then generated.

In other words, the optical sensor used in the mug cup has the function of sensing light and simultaneously closing an electrical circuit contrary to the unattended light with an optical sensor capable of sensing light and simultaneously opening an electrical circuit.

The melody kit 12 including the memory chip 12 and the like is constructed as a kit like its name and then employed in other kitchenware or a variety of products. As another example, there is a kind of Christmas card in which a melody is generated when the card is unfolded but is not generated when it is folded.

Such a Christmas card is identical with the melody mug cup in view of their components except operation activation of the optical sensor, i. e. the principle of shutting off light and releasing the shutting state.

Meanwhile, as described above, conventional kitchenware including the mug cup using the melody kit constructed as such can obtain only a simple advantage in that a melody is generated in response to changes in the position of relevant kitchenware.

That is, there is an essential problem in that changes in the state of contents within kitchenware other than the changes in the position of the kitchenware cannot be sensed. Further, in view of a response to the changes in the position of the kitchenware, it cannot be expected to obtain uses beyond the simple generation of a melody, i. e. the generation of simple special effects for celebrating a variety of anniversaries and the like.

Disclosure of Invention The present invention is conceived to solve the problems and disadvantages in the prior art. An object of the present invention is to provide heat sensing kitchenware, wherein if the temperature of contents within kitchenware is below or above a predetermined temperature, a variety of responses such as generation of a melody or warning sound or a lighting operation are made according to the sensed results.

Heat sensing kitchenware of the present invention for achieving the object is constructed such that, if the temperature of contents within kitchenware is below or above a predetermined temperature, a sensing means including an optical sensor senses the temperature and then makes a response such as generation of a melody or warning

sound or a lighting operation.

The amount of heat that the contents within the kitchenware have is converted into the operation of the optical sensor using a heat sensing property of a temperature- sensitive color-changing ink.

The temperature-sensitive color-changing ink is a material in which a temperature-sensitive color-changing pigment obtained by microencapsulating an electron-donating coloring organic compound (color former), an electron-accepting compound (developer) and a desensitizing agent with urethane resin, epoxy resin, melamine resin or the like and pulverizing the microencapsulated pigment is dispersed in a transparent medium such as epoxy resin, polyester resin or the like. The temperature- sensitive color-changing ink has very unique properties by which a unique specific color is exhibited to be opaque at low temperature below a predetermined temperature due to the occurrence of mutual bonding of the three components including the color former, whereas the unique color disappears to be transparent at high temperature above the predetermined temperature due to the occurrence of separation of the components.

Heat sensing kitchenware according to an embodiment of the present invention employed, upon manufacture thereof, a temperature-sensitive color-changing ink product in which thermo-chromic microcapsule powder available from Sakura Color Products Co. in Japan is dispersed in a transparent medium such as epoxy resin, polyester resin or the like. Since the subject of the present invention is to use a heat sensing property of temperature-sensitive color-changing ink as an optical sensor activating means, detailed descriptions of the principle or structure of the optical sensor and the temperature- sensitive color-changing ink themselves will be omitted.

Since the temperature of a temperature-sensitive color-changing ink at which its original color disappears to be transparent (hereinafter, referred to as"color-changing temperature) is predetermined such that commercially available inks have unique values of the temperature, respectively, a user can merely select any proper product suitable for required color-changing conditions.

The heat sensing kitchenware of the present invention using the optical sensor and the property of the temperature-sensitive color-changing ink essentially has a sensing

means, comprising a melody kit and the like together wit the optical sensor, attached thereon and a member with the temperature-sensitive color-changing ink applied thereon (hereinafter, referred to as a"temperature-sensitive color-changing member") is placed close to the optical sensor.

That is, as a result of a change of the temperature-sensitive color-changing member into a colored opaque member or a colorless transparent member according to the temperature of the contents in the kitchenware, light incident on the optical sensor is shut off or the amount of the incident light increases, which is sensed by the optical sensor that in turn closes an electrical circuit. The entire sensing means then operates in response to the closing of the electrical circuit. Therefore, a variety of responses such as the generation of a melody or warning sound described above are made.

Upon manufacture of the heat sensing kitchenware of the present invention, two kinds of temperature-sensitive color-changing inks are used separately. One of them has a color-changing temperature of 15°C and the other has a color-changing temperature of45°C.

In case of the temperature-sensitive color-changing ink with the color-changing temperature of 15 °C, it is used for heat sensing kitchenware constructed such that the sensing means operates when the contents in the kitchenware are at low temperature below 15°C, i. e. when the kitchenware contains a cool beverage or the like (hereinafter, referred to as"low temperature sensing type kitchenware"). On the other hand, in case of the temperature-sensitive color-changing ink with the color-changing temperature of 45 °C, it is used for heat sensing kitchenware constructed such that the sensing means operates when the contents in the kitchenware are at high temperature above 45°C, i. e. when the kitchenware contains hot coffee or the like (hereinafter, referred to as"high temperature sensing type kitchenware").

Further, upon manufacture of the heat sensing kitchenware of the present invention, two kinds of optical sensors are separately used according to whether the kitchenware is a low temperature sensing type or a high temperature sensing type. One of them is a circuit-opening type optical sensor and the other is a circuit-closing type optical sensor.

In case of an optical sensor with a structure in which an electrical circuit is opened when light is sensed, i. e. the circuit-opening optical sensor, it is used for the low temperature sensing type kitchenware. On the contrary, in case of an optical sensor with a structure in which an electrical circuit is closed when light is sensed, i. e. the circuit-closing optical sensor, it is used for the high temperature sensing type kitchenware.

The reasons of the separate use thereof will be more specifically described by way of example in connection with the low temperature sensing type kitchenware using the temperature-sensitive color-changing ink with the color-changing temperature of 15 °C together with the circuit-opening optical sensor.

In a case where the low temperature sensing type kitchenware is at a temperature below 15°C where the temperature-sensitive color-changing member coated with the temperature-sensitive color-changing ink becomes to be colored and opaque and thus light incident on the optical sensor is shut off, the electrical circuit of the sensing means comprising the optical sensor is closed to make a response such as generation of a melody or the like. On the other hand, at room temperature above 15°C where the temperature-sensitive color-changing member becomes to be colorless and transparent and thus light is incident on the optical sensor, the electrical circuit of the sensing means comprising the optical sensor is opened to make no response. Such a mechanism is opposite to that of the high temperature sensing type kitchenware.

Due to such fundamental differences between the low temperature sensing type kitchenware and the high temperature sensing type kitchenware, they employ different optical sensors with opposite operating mechanisms. Thus, it is necessary to note these differences upon understanding of the structure described herein.

Brief Description of Drawings Fig. 1 a is a partial sectional view showing a conventional melody mug cup.

Fig. lb is a view showing a melody kit constituting the mug cup of Fig. la.

Fig. 2a is a partial sectional view showing heat sensing kitchenware according to a first embodiment of the present invention.

Fig. 2b is a view showing a sensing means in the heat sensing kitchenware according to the first embodiment of the present invention.

Fig. 3a is a partial sectional view showing heat sensing kitchenware according to a second embodiment of the present invention.

Fig. 3b is a view showing a sensing means in the heat sensing kitchenware according to the second embodiment of the present invention.

<Explanation of reference numerals for designating main components in the drawings> 20,30 : Heat sensing kitchenware 21: Body 22,33 : Sensing means 23: Cover plate 31 : Inner case 32: Outer case 34: Enclosure pack S: Optical sensor Best Mode for Carrying Out the Invention Hereinafter, heat sensing kitchenware according to preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Referring to Fig. 2a showing heat sensing kitchenware according to a first embodiment of the present invention, although a body 21 or a sensing means 22 appears to be identical with that of the aforementioned conventional mug cup in view of their shapes, a structure on a cover plate 23 is apparently different from that of the conventional mug cup, as shown in Fig. 2b.

That is, the heat sensing kitchenware 20 according to a first embodiment of the present invention is identical with a conventional mug cup in that the heat sensing kitchenware 20 also comprises the opaque body 21 having an inner space for containing contents such as coffee or beverages and formed with an installation space for receiving a sensing means at an outer surface thereof, the sensing means 22 including an optical sensor S and installed within the installation space at the surface of the body 21, and the cover plate 23 bonded to an entrance of the installation space on the body 21 to close the

installation space. However, the cover plate 23 is characterized in that a temperature- sensitive color-changing ink is applied to a portion thereof (designated by"B") and the other portion (designated by"A") is processed opaquely.

The opaque processing does not mean specific processing, but means that on the cover plate 23 made of a general transparent synthetic resin material, the other portion A except the portion B with the temperature-sensitive color-changing ink applied thereto is made to be opaque.

For example, it can be contemplated that a general ink or paint is applied to the portion A, or a coloring vinyl film or the like as an opaque body is attached thereto.

That is, the portion B of the cover plate 23 with the temperature-sensitive color- changing ink applied thereto is caused to serve as the temperature-sensitive color- changing member described above.

In an actual manufacturing process, it is preferred that a general ink or the like be applied in advance to the portion A prior to the installation of the sensing means 22 on the cover plate 23.

Meanwhile, although a circuit board, a melody chip, a battery and a speaker in the first embodiment of the present invention are components with structures identical with those of conventional ones, they are designated by additional reference numerals "22a, ""22b, ""22c,"and"22d"for unity in denotation of them and the heat sensing kitchenware 20 according to the first embodiment of the present invention.

The operating principle of the heat sensing kitchenware 20 according to the first embodiment of the present invention will be described with reference to Figs. 2a and 2b.

For better understanding, the description thereof will be made by assuming that the heat sensing kitchenware 20 according to the first embodiment of the present invention is high temperature sensing type kitchenware.

In a normal state where the body 21 is maintained below 45°C, there is no light introduced into the closed space at a lower end of the body 21 in which the sensing means 22 is installed.

If hot contents such as coffee at a temperature of 45 °C or higher is contained in the kitchenware, however, the temperature-sensitive color-changing ink applied to the

portion B of the cover plate 23 is changed to be transparent according to the properties and principle thereof described above.

As a result, light is introduced through the portion B that has been transparent, and the optical sensor S (in this case, a circuit-closing type optical sensor) placed adjacent thereto senses the light and simultaneously closes an electrical circuit of the sensing means 22.

That is, a melody kit constituting the sensing means 22 is operated to output a melody.

The illustrated kitchenware 20 has been described on the assumption that it is the high temperature sensing type kitchenware. On the contrary, if the kitchenware 20 is low temperature sensing type kitchenware, it is identical with the high temperature sensing type kitchenware except that the temperature-sensitive color-changing ink applied to the portion B is a temperature-sensitive color-changing ink with a color- changing temperature of 15°C and the optical sensor S is a circuit-opening type optical sensor rather than the circuit-closing type optical sensor.

Meanwhile, the optical sensor S in the heat sensing kitchenware 20 of the first embodiment has a structural feature that it is positioned within a dark space with no incident light in a normal state. However, since there is a great need for manufacture of the heat sensing kitchenware of the present invention out of a transparent synthetic resin material, heat sensing kitchenware in which light is always introduced thereinto will be described as a second embodiment of the present invention.

That is. the heat sensing kitchenware according to the second embodiment of the present invention will be described with reference to Figs. 3 a and 3b.

Like the description of the heat sensing kitchenware of the first embodiment, the heat sensing kitchenware 30 is assumed to be high temperature sensing type kitchenware.

Even in this case, a circuit board, a melody chip, a battery and a speaker are <BR> <BR> designated by additional reference numerals"33a, ""33b,""33c,"and"33d"for unity in denotation of them and the heat sensing kitchenware 30 according to the second embodiment of the present invention.

Since light is always introduced into a sensing means 33 constituting the heat

sensing kitchenware 30 according to the second embodiment of the present invention as described above, it is necessary to shut off light incident on the optical sensor S at least in a normal state so as to prevent an abnormal phenomenon in which the optical sensor S receives the light and continuously opens or closes the electrical circuit.

An enclosure pack designated by reference numeral 34 is a thin film member for surrounding the optical sensor S and has a temperature-sensitive color-changing ink applied to both or either of surfaces thereof.

On the assumption that the heat sensing kitchenware 30 is high temperature sensing type kitchenware, the ink applied to the enclosure pack 34 has a color-changing temperature of 45 tC, and the optical sensor S concealed therein is the circuit-closing type optical sensor as described above.

That is, when hot contents such as a beverage at a temperature of 45 °C or higher are contained in the kitchenware 30, the temperature-sensitive color-changing ink applied to the enclosure pack 34 becomes transparent and light is introduced therethrough so that the optical sensor S in the enclosure pack 34 senses the light and closes the electrical circuit.

As a result, it is apparent that the entire sensing means 33 including the optical sensor is operated to output a melody.

Meanwhile, although the illustrated heat sensing kitchenware 30 has a thermal insulation dual structure established by a combination of inner and outer cases 31 and 32 which are made of a transparent synthetic resin material, it is only for illustrative purposes to show a structure in which light is always incident on the sensing means 33 installed at a lower end surface of the inner case 31, and it does not mean that the heat sensing kitchenware according to the second embodiment of the present invention is limited to transparent kitchenware with a dual structure.

Further, although the aforementioned embodiments have been described by way of example in connection with a cup, another embodiment may be implemented by mounting a sensing means at a body portion, including a handle, of a fry pan (not shown) and closing the sensing means with an additional cover plate (not shown).

In this case, the sensing means plays an important role as a safety device that

notifies a user of heating of the fry pan until the fry pan is heated to a proper temperature or when the user temporarily goes away from the fry pan during cooling.

As described above, since those skilled in the art can readily select a single or double structure, a transparent or opaque structure, or alternative application of the present invention to other kitchenware such as a fry pan, it should be understood that various modifications, which can be made without departing from the technical spirit of the present invention by which the heat sensing property of a temperature-sensitive color-changing ink and the light sensing property of an optical sensor are applied to heat sensing kitchenware, fall within the scope of the present invention.

Moreover, although the embodiments have been described by way of example as generating a melody as an output, i. e. a response, for representing heat sensing results of the optical sensor to the outside, it is also possible to select other useful response forms.

In other words, in a case where a different response other than the generation of a melody is made to the opening or closing of an electrical circuit by an optical sensor S, for example, in kitchenware constructed to call a user's attention by a buzzer, the sensing means 22 and 33 comprise a buzzer (not shown) other than the melody kit; and in kitchenware constructed to turn on a red warning light, the sensing means 22 and 33 comprise a red small lamp (not shown).

Although the illustrated embodiments of the heat sensing kitchenware of the present invention have been described by way of example in connection with a mug cup, the technical spirit of the present invention can also be applied directly to other kitchenware such as a fry pan, a cookpot, a bowl, a thermos bottle, a kettle and a rice cooker. Therefore, it should be understood that the present invention covers the whole kitchenware in the inclusive meaning.

Industrial Applicability As described above, the heat sensing kitchenware of the present invention senses whether the contents in the kitchenware are hot or cool and makes a variety of responses to the sensed results, such as generation of a melody or warning sound, or lighting. It is believed that the present invention is very useful as a special effect device, a safety

device or kitchenware in daily life.

That is, the present invention relating to the heat sensing kitchenware is applicable to a wide range of industrial fields as well as kitchenware.