JP2604396Y2 - Coil device for high frequency induction heating - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-frequency induction heating coil device for heating a workpiece by a high-frequency induction current, and more particularly to a high-frequency induction heating coil device capable of heating a small-diameter work inner surface.

[0002]

2. Description of the Related Art Conventionally, when hardening the inner surface of a work by using a high-frequency induction current, for example, a method disclosed in Japanese Utility Model Application Laid-Open No.
The coil device disclosed in Japanese Unexamined Patent Publication No. 92455 or Japanese Utility Model Publication No. 62-8158 is used. All of these coil devices are formed by bending a copper pipe into a predetermined shape so that its outer diameter is slightly smaller than the inner diameter of the work to be hardened, and supply cooling water into the pipe. The work is heated while circulating.

[0003]

[Problems to be Solved by the Invention] However, the above-mentioned coil device has a problem that it cannot be applied to, for example, a work having a small inner surface. That is, since it is necessary to circulate the cooling water in the pipe forming the coil device, the minimum diameter of the pipe to be used is inevitably determined, and the outer diameter of the coil obtained by bending the pipe is limited.
Therefore, for example, in the case of a work having an inner surface with a diameter of 10 mm or less, quenching with the above-described coil device is difficult, and it is a reality that quenching is performed by a method other than induction hardening.

In the above-described coil device,
Even if a coil device having a small diameter to some extent can be manufactured, there is a problem that the manufacturing of the coil device is very troublesome, for example, the operation of bending the pipe requires skill.

The present invention has been made in view of the above circumstances, and even if the inner surface of a work is small, it can be hardened by a high-frequency induction current, and its manufacture can be performed extremely easily. It is an object of the present invention to provide a coil device for high-frequency induction heating that can be performed.

[0006]

Means for Solving the Problems In order to achieve the object, a coil device for high-frequency induction heating of the present invention includes a rod-shaped core, a coil wound around the core and supplied with a high-frequency current, A non-conductive cover accommodating the coil and the core in a substantially sealed state; a supply member for supplying cooling water separate from the core is disposed in the cover; and a discharge port is provided at an upper portion of the cover. And a cooling water supply port of the supply member is located at a substantially lower end of the core.

[0007]

In the coil device for high-frequency induction heating according to the present invention, the coil wound around the core is accommodated in the cover, and high-frequency current is supplied to the coil and cooling water is supplied into the cover via the supply member. . The magnetic flux generated from the coil efficiently heats the inner surface of the work by the core, and is subjected to, for example, a quenching process. The coil and the core are supplied to the lower end of the core in the cover from the supply port of the supply member, and this is effectively cooled by cooling water flowing upward in the cover and discharged outside the cover from the discharge port provided in the upper part. The heat generation is prevented. Thus, the coil device itself can be formed in a small size, and high-frequency induction heating of the inner surface of a small-diameter work becomes possible.

[0008]

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. 1 and 2 are cross-sectional views of a coil device for high-frequency induction heating according to the present invention. In the figure, a coil device 1 has a coil 3 made of a copper wire or the like wound around a rod-shaped core 2 a predetermined number of times, and this coil 3 is housed in a non-conductive cover 4 made of, for example, glass, ceramics or the like. Have been. Both ends of the coil 3 are covered
The terminals 5, 6 protrude from the upper surface 4a. Further, a supply member 8 and a discharge member 9 for the cooling water 7 formed of, for example, a pipe are disposed on the upper surface 4 a of the cover 4, and the lower end 8 a of the supply member 8 is located near the bottom surface 4 b of the cover 4. .

The terminals 5 and 6 are electrically connected to output terminals of the high-frequency generator 10, and the supply member 8 and the discharge member 9 are connected to a cooler 11 by hoses or the like. The connection between the upper surface 4a of the cover 4 and the supply member 8, the discharge member 9, and the like is sealed, so that the inside of the cover 4 is substantially closed.

Next, a method of using the coil device 1 will be described. First, the coil device 1 is inserted into the hole 12a to be quenched of the work 12 which is the material to be heated, and the high frequency generator 10 is operated to attach the coil
Supply high frequency current of KHZ (kilohertz). Also,
Simultaneously with the operation of the high-frequency generator 10, the cooler 11 is operated to supply the cooling water 7 to the supply member 8.

When a high-frequency current is supplied to the coil 3, a magnetic flux is generated.
Hole 12a is heated and quenched. At this time, since the coil 3 is wound around the core 2, a magnetic flux having a large density can be obtained, and the work 12 is efficiently heated. On the other hand, the supply of the high-frequency current to the coil 3 causes the coil 3 and the core 2 to generate heat. The cooling water 7 supplied from the supply member 8 suppresses the heat generation.

At this time, the flow of the cooling water 7 generated in the cover 4 from below to above causes the coils 3
Etc. are cooled. That is, the cold cooling water 7 supplied from the cooler 11 is supplied from the lower end 8a of the supply member 8 to the bottom surface 4b in the cover 4, and is heated while cooling the coil 3 and the like. The lightened cooling water rises in the cover 4 and returns from the discharge member 9 to the cooler 11. Thereby, the flow of the cooling water 7 is generated, and the cover 4
It does not stay inside. Once the prescribed quenching is performed,
The coil device 1 is taken out from the hole 12a of the work 12, the work 12 is cooled with a coolant or the like, and the quenching operation is completed.

As described above, according to the above embodiment, the coil 3 is wound around the rod-shaped core 2, the coil 3 is accommodated in the cover 4, and the work 12 is cooled while cooling the core 2 and the coil 3 with cooling water. The diameter t of the coil device 1 for quenching
(See FIG. 1), for example, when the inner diameter is 1
Even with a small hole 12a of 0 mm or less, induction hardening of its inner surface is possible. Especially, 100KHZ or 200KH
Even at a high frequency such as Z, quenching with a high-frequency current is possible without deterioration of the core 3 and the like, and a high-precision surface treatment that has been impossible in the past can be performed.

Further, since the coil device 1 can be manufactured simply by winding the coil 3 made of a copper wire or the like around the core 2 and housing the coil 3 in the cover 4, the manufacturing operation is extremely simple. Further, the cooling water 7 circulates in the cover 4 and the cooling water 7
Because there is no stagnation in the cover 4, the coil 3 and the like can be effectively cooled. Accordingly, the diameter of the core 2 and the like can be reduced, and the coil device 1 can be further reduced in size.

In the above embodiment, the case where the inner surface of the workpiece 12 to be quenched is the hole 12a has been described, but the present invention is not limited to this.
It may be a semicircular recess. In the above embodiment, the cover 4 is formed in a cylindrical shape, but the cover 4 may be formed in an appropriate shape according to the shape of the inner surface of the work 12 to be hardened. Further, in the above-described embodiment, a plurality of ejection holes may be provided on the lower side surface of the supply member 8 so that the cooling water is ejected from the ejection holes, or the flow of the cooling water 7 in the cover 4 is controlled. Needless to say, various modifications can be made without departing from the scope of the present invention, for example, by providing a partition plate on the inner wall of the cover 4.

[0016]

As described above in detail, according to the coil device for high-frequency induction heating of the present invention, the coil wound around the core is accommodated in the conductive cover through which the cooling water circulates. The coil device itself can be reduced in size, for example, high-frequency induction heating of the inner surface of a small-diameter work becomes possible,
A high-precision surface treatment can be performed, and the coil device can be easily manufactured. In addition, since the supply port of the supply member is located at a substantially lower end of the core, it is possible to supply cold cooling water to the core and the coil, and to efficiently suppress heat generation of the coil and the like. This has the effect of enabling further downsizing.

[Brief description of the drawings]

FIG. 1 is a sectional view of a coil device for high-frequency induction heating according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG. 1;

[Explanation of symbols]

1: Coil device 2: Core 3: Coil 4: Cover 7: Cooling water 8: Supply member 9: Discharge member 10: High frequency generator 1
1: Cooler 12: Work

Claims (1)

(57) [Scope of request for utility model registration] 1. A cover comprising: a rod-shaped core; a coil wound around the core and supplied with a high-frequency current; and a non-conductive cover for enclosing the coil and the core in a substantially sealed state. A supply member for supplying cooling water separate from the core is disposed therein, and a discharge port is provided at an upper portion of the cover, and a supply port of the cooling water of the supply member is positioned at a substantially lower end of the core. A coil device for high frequency induction heating characterized by the following.