Induction heating device

Patent metadata

Field	Value
Publication number	US-8993941-B2
Application number	US-201013381492-A
Country	US
Kind code	B2
Filing date	Mar 16, 2010
Priority date	Jul 3, 2009
Publication date	Mar 31, 2015
Grant date	Mar 31, 2015

Abstract

Plural induction heating coils for inductively heating to-be-heated object are provided under a top plate on which to-be-heated object is placed, and plural inverter circuits for supplying high-frequency currents to the plural induction heating coils, respectively, are adapted to be cooled by cooling air flows from cooling portions, and placed in a longitudinal row along the cooling air flows, in air-flow blowing path spaces through which cooling air flows from the cooling portions are blown, so as to facilitate cooling designing for an induction heating device and to improve the cooling performance of the induction heating device.

First claim

The invention claimed is:

1. An induction heating device comprising:
a top plate on which a to-be-heated object is allowed to be placed;
plural induction heating coils for inductively heating the to-be-heated object, the induction heating coils being placed just under the top plate;
plural inverter circuit boards for supplying high-frequency currents to the plural induction heating coils, respectively and comprising plural inverter circuits mounted thereon; and
cooling portions comprising a blowing port for blowing cooling air to the plural inverter circuit boards, each blowing port associated with and corresponding to each inverter circuit board;
wherein the plural inverter circuits on each inverter circuit board are placed under the plural induction heating coils with an air-flow blowing path formed there between and cooling air flows from each cooling portion through the air-flow blowing path space, the plural inverter circuits on each inverter circuit board arranged side by side forming a longitudinal row and the cooling air flowing along the longitudinal row of the plural inverter circuits,
wherein each of the plural inverter circuits comprises:
a fin area having a cooling fin on which at least a switching device is mounted, and
a mounted-component area provided with a heat-generating mounted component to be directly cooled by the cooling air flows, wherein the fin area and the mounted-component area are separated from each other in each inverter circuit, and

wherein fin areas of the plural inverter circuits are arranged side by side to form a longitudinal row of the fin areas in each inverter circuit board and mounted-component areas of the plural inverter circuits are arranged side by side to form a longitudinal row of the mounted-component areas in each inverter circuit board,
wherein the blowing port corresponding to each inverter circuit board is arranged to send cooling air directly both to the longitudinal row of the fin areas and the longitudinal row of the mounted-component areas through a respective air-flow blowing path formed in the fin areas and the mounted-component areas;
wherein the cooling air having passed through one of the fin area continues to flow through the longitudinal row of the remaining fin areas in a first cooling path, and the cooling air having passed through one of the mounted-component areas continues to flow through the longitudinal row of the remaining mounted-component areas in a second cooling path, respectively, the longitudinal row of the fin areas being spaced apart and separated from the longitudinal row of the mounted-component areas such that the first cooling path and the second cooling path are separated from each other in each inverter circuit board, and the cooling air flowing in the first cooling path has a volume larger than a volume of the cooling air flowing in the second cooling path,
wherein the cooling air flowing in the first cooling path and the cooling air flowing in the second cooling path flow in the same direction.

2. The induction heating device according to claim 1 , wherein:
the plural inverter circuits comprise a first inverter circuit for supplying a high-frequency current to an induction heating coil having a larger maximum output, and a second inverter circuit for supplying a high-frequency current to an induction heating coil having a smaller maximum output,
the first inverter circuit is provided closer to the corresponding blowing port in the cooling portion than to the second inverter circuit, the first inverter circuit is placed in an upwind side with respect to the second inverter circuit, and the cooling air flowing from the cooling portion passes through the second inverter circuit, after passing through the first inverter circuit.

3. The induction heating device according to claim 2 , wherein
the plural inverter circuits are provided with each of switching devices mounted on different cooling fins, and
the cooling air flowing from the cooling portion pass through the cooling fin on which the switching device in the second inverter circuit is mounted, after passing through the cooling fin on which the switching device in the first inverter circuit is mounted.

4. The induction heating device according to claim 1 , wherein
the plural inverter circuits each include a cooling fin on which at least a switching device is mounted, and
a rectifier for supplying a power supply to the plural inverter circuits is mounted on the cooling fin of the inverter circuit provided most closely to a blowing port in the cooling portion.

5. The induction heating device according to claim 1 , wherein:
the plural inverter circuits comprise a first inverter circuit and a second inverter circuit, the first inverter circuit being placed in an upwind side with respect to the second inverter circuit in a longitudinal row,
the induction heating device includes a power-supply circuit for supplying electric power to each of the first inverter circuit and the second inverter circuit, and a control circuit for controlling the electric power supplied to each of the first inverter circuit and the second inverter circuit, and
the control circuit is adapted such that a total output value constituted by an output of the first inverter circuit and an output of the second inverter circuit is preliminarily set, and is adapted to perform control for allocating an output within the total output value, as the output of the first inverter circuit and the output of the second inverter circuit.

6. The induction heating device according to claim 1 , wherein
a power-supply circuit for supplying electric power to each of the plural inverter circuits is juxtaposed to the cooling portion and is placed at a place where the power-supply circuit does not directly undergo the cooling air flowing from the cooling portion.

7. The induction heating device according to claim 1 , wherein
the plural inverter circuits placed in a longitudinal row are covered with a duct or at least at portions thereof, and cooling air flowing from the cooling portion are blown through the duct.

8. The induction heating device according to claim 1 , wherein each inverter further comprises a partition rib for separating the cooling air passing through the fin area in the first cooling path from the cooing air passing through the mounted-component area in the second cooling path.

9. The induction heating device according to claim 1 , wherein each of the cooling fins provided in the plural inverter circuits is shaped to have substantially the same cross-sectional shape orthogonal to the first cooling path of the cooling air flowing from the cooing portion.

10. The induction heating device according to claim 1 , wherein
the plural inverter circuits comprise a first inverter circuit and a second inverter circuit,
the inverter circuits are each configured to create a high-frequency current using two switching devices in a high-voltage side and a low-voltage side,
different cooling fins are mounted on the respective switching devices, and the respective cooling fins of the first and second inverter circuits are placed side by side to form a longitudinal row of the cooling fins and the first cooling path forms a substantially straight line path,
the cooling air passes first the cooling fin mounted on the high-voltage-side switching device in the first inverter circuit which is placed at a position closest to a blowing port of the cooling portion, and then, sequentially passes the cooling fin mounted on the low-voltage-side switching device in the first inverter circuit, the cooling fin mounted on the high-voltage-side switching device in the second inverter circuit, and the cooling fin mounted on the

Assignees

• Kataoka Akira
• Kusaka Takaaki
• Shigeoka Takehiko
• Matsui Eiji
• Kitaizumi Takeshi
• Panasonic Ip Man Co Ltd

Inventors

• Kataoka Akira
• Kusaka Takaaki
• Shigeoka Takehiko
• Matsui Eiji
• Kitaizumi Takeshi

Classifications

• H05B6/1263 Primary

  using coil cooling arrangements · CPC title