Abstract: An induction heating device includes a top plate arranged to have an object placed thereon, a heating coil provided under below the top plate for heating the object, a sensor provided under the top plate for detecting a temperature of the object, a judging unit for judging whether or not the object is positioned directly above the sensor, a controller operable to allow the heating coil to heat the object in response to the temperature detected by the sensor detecting, and a position indicator provided at the top plate for indicating a position of the sensor. The position indicator includes a detectable area of the sensor, and is larger than the detectable area. This induction heating device securely positions the object directly above the sensor and detects a temperature of the object accurately, hence heating the object accurately at a predetermined temperature.

Abstract: An induction heating device has an accurate sensing of the temperature of a to-be-heated object and is user-friendly. The induction heating device includes a sensor for sensing the temperature of the to-be-heated object and can carry out a heating operation only when it is determined that the to-be-heated object exists above the sensor. A display having a circular design and characters, for example, that shows the position of this sensor is provided on a top plate of the induction heating device.

Abstract: An infrared permeable window 4a, which is surrounded by a light shielding layer 7b and is narrower than an infrared sensor display window 4g, is formed inwardly of the infrared sensor display window 4g, and an infrared incident area 43a for detecting infrared rays of light and a light emitting unit 56a are provided below the infrared permeable window 4a. Also, a light emitting surface 4b is provided inwardly of the infrared permeable window 4a, so that the user can assuredly place a cooking container P on the infrared permeable window 4a.

Abstract: An induction heater which has an electrical conductor between a heating coil and a top plate. The electrical conductor has an extended portion formed downward from its outer periphery. The extended portion has a connector at its tip for coupling to a low-potential part. A thermal-connection reducing means is provided on the extended portion. A cross-sectional shape near a bent portion of the extended portion is made uniform. With the above structure, the electrical conductor has both the functions of decreasing the buoyancy and electrostatic shielding. This structure uses a smaller number of components, eliminates the risk of electric shock to the human body, and prevents uplift of an object to be heated. The thermal-connection reducing means reduces heat conduction to a connected part. Accordingly, a highly reliable and compact apparatus becomes available.

Abstract: An induction heating device includes a top plate arranged to have an object placed thereon, a heating coil provided under below the top plate for heating the object, a sensor provided under the top plate for detecting a temperature of the object, a judging unit for judging whether or not the object is positioned directly above the sensor, a controller operable to allow the heating coil to heat the object in response to the temperature detected by the sensor detecting, and a position indicator provided at the top plate for indicating a position of the sensor. The position indicator includes a detectable area of the sensor, and is larger than the detectable area. This induction heating device securely positions the object directly above the sensor and detects a temperature of the object accurately, hence heating the object accurately at a predetermined temperature.

Abstract: An infrared permeable window 4a, which is surrounded by a light shielding layer 7b and is narrower than an infrared sensor display window 4g, is formed inwardly of the infrared sensor display window 4g, and an infrared incident area 43a for detecting infrared rays of light and a light emitting unit 56a are provided below the infrared permeable window 4a. Also, a light emitting surface 4b is provided inwardly of the infrared permeable window 4a, so that the user can assuredly place a cooking container P on the infrared permeable window 4a.

Abstract: An induction heater which has an electrical conductor between a heating coil and a top plate. The electrical conductor has an extended portion formed downward from its outer periphery. The extended portion has a connector at its tip for coupling to a low-potential part. A thermal-connection reducing means is provided on the extended portion. A cross-sectional shape near a bent portion of the extended portion is made uniform. With the above structure, the electrical conductor has both the functions of decreasing the buoyancy and electrostatic shielding. This structure uses a smaller number of components, eliminates the risk of electric shock to the human body, and prevents uplift of an object to be heated. The thermal-connection reducing means reduces heat conduction to a connected part. Accordingly, a highly reliable and compact apparatus becomes available.

Abstract: An induction heating device is provided that can realize an accrete sensing of the temperature of a to-be-heated object and that is user-friendly. To realize this, the induction heating device includes a sensor for sensing the temperature of the to-be-heated object and can carry out a heating operation only when it is determined that the to-be-heated object exists above the sensor. A display having a circular design and characters for example that shows the position of this sensor is provided on a top plate of the induction heating device.

Abstract: An induction heating coil having little high-frequency loss and producing little hast is easily manufactured by covering a conductor with a first insulating material to form a wire, then bundling and twisting such wires to form a stranded wire, covering the outer surface of the stranded wire with a second insulating material to form a coil wire, winding the coil wire a certain number of turns into a coil portion having a certain shape. The end portion of the coil portion and a connecting portion are heated with Joule heat while applying pressure to the end portion at the same time, so that the first and second insulating materials are fused and pressure-bonded to the conductor. Thus a terminal portion for the external connection of the coil portion is fixed while keeping the electrical connection with the conductor. Accordingly, an induction heating coil of low cost and stable quality can be easily manufactured.

Abstract: An electric conductor provided for decreasing a lifting force exerted on an object being heated has an aperture of a small diameter in the center thereof, which leaves a large surface area to enhance reduction of the lifting force. The electric conductor is also provided with a comb section around the aperture for preventing a circling current induced in the electric conductor from flowing into an area around the aperture. This structure can thus alleviate excessive heating around the aperture, and allow the heating coil to produce a high output power for a long duration of time even when an inwardly concaved pan is used.

Abstract: An induction heating coil having little high-frequency loss and producing little hast is easily manufactured by covering a conductor with a first insulating material to form a wire, then bundling and twisting such wires to form a stranded wire, covering the outer surface of the stranded wire with a second insulating material to form a coil wire, winding the coil wire a certain number of turns into a coil portion having a certain shape. The end portion of the coil portion and a connecting portion are heated with Joule heat while applying pressure to the end portion at the same time, so that the first and second insulating materials are fused and pressure-bonded to the conductor. Thus a terminal portion for the external connection of the coil portion is fixed while keeping the electrical connection with the conductor. Accordingly, an induction heating coil of low cost and stable quality can be easily manufactured.

Abstract: An electric conductor provided for decreasing a lifting force exerted on an object being heated has an aperture of a small diameter in the center thereof, which leaves a large surface area to enhance reduction of the lifting force. The electric conductor is also provided with a comb section around the aperture for preventing a circling current induced in the electric conductor from flowing into an area around the aperture. This structure can thus alleviate excessive heating around the aperture, and allow the heating coil to produce a high output power for a long duration of time even when an inwardly concaved pan is used.