JPH0633396U - Coil device for high frequency induction heating - Google Patents

Abstract

(57) [Abstract] [Purpose] A coil device for high frequency induction heating, which enables quenching and the like by a high frequency induction current even if the inner surface of the work has a small diameter and can be manufactured extremely easily. I will provide a. A coil (3) wound around a rod-shaped core (2) and supplied with a high frequency current is housed in a cover (4), and cooling water (7) is placed on an upper surface (4a) of the cover (4). Is provided with a supply port (8) and a discharge port (9), and cooling water is supplied from the supply port (8) into the cover (4) to cool the core (2) and the coil (3).

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a coil device for high-frequency induction heating that heats a work by a high-frequency induction current, and particularly to a coil device for high-frequency induction heating that can heat even the inner surface of a work having a small diameter.

[0002]

[Prior art]

 Conventionally, when quenching the inner surface of a work using a high frequency induction current, the coil device disclosed in, for example, Japanese Utility Model Publication No. Sho 63-192455 or Japanese Utility Model Publication No. 62-8158 is used. In each of these coil devices, a copper pipe is bent into a predetermined shape so that its outer diameter is slightly smaller than the inner diameter of the workpiece to be quenched, and cooling water is supplied to the pipe. The work is heated while being circulated.

[0003]

[Problems to be solved by the device]

 However, the above coil device has a problem that it cannot be applied to a work having an inner surface of a small diameter, for example. 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 also limited. Therefore, for example, in the case of a work having an inner surface having a diameter of 10 mm or less, it is difficult to quench with the coil device as described above, and it is a fact that quenching is performed by a method other than the induction quenching. Further, in the above coil device, even if a coil device having a small diameter can be manufactured to some extent, it is very troublesome to manufacture the coil device because it requires skill to bend the pipe. There was a point. The present invention has been made in view of the above circumstances, and even if the inner surface of the work has a small diameter, it can be hardened by a high frequency induction current and can be manufactured extremely easily. It is an object of the present invention to provide a coil device for high frequency induction heating.

[0004]

[Means for Solving the Problems]

 In order to achieve such an object, a coil device for high frequency induction heating according to the present invention comprises a rod-shaped core, a coil wound around the core and supplied with a high frequency current, and the coil and the core are substantially sealed. And a non-conductive cover that is housed in the cover, the cover is provided with a cooling water supply port and a cooling water discharge port, and cooling water is supplied from the supply port into the cover to cool the core and the coil. To do. Further, in the above coil device, the supply port is located below the discharge port.

[0005]

[Action]

 In the coil device for high frequency induction heating of the present invention, the coil wound around the core is housed in the cover, and the high frequency current is supplied to the coil and the cooling water is supplied in the cover. The magnetic flux generated from the coil efficiently heats the inner surface of the work by the core, and is subjected to, for example, quenching treatment. The coil and core are cooled by cooling water circulating inside the cover to prevent heat generation. As a result, the coil device itself can be formed in a small size, and high frequency induction heating of the inner surface of the work having a small diameter becomes possible. Further, by arranging the cooling water supply port below the discharge port, a cooling water flow from the lower side to the upper side is generated in the cover, effectively suppressing heat generation of the core and the like.

[0006]

【Example】

 An embodiment of the present invention will be described below in detail with reference to the drawings. 1 and 2 are 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 the coil 3 is housed in a non-conductive cover 4 made of, for example, glass, ceramics or the like. Has been done. Both ends of the coil 3 project from the upper surface 4a of the cover 4, and terminals 5 and 6 are fixed to the ends thereof. A supply member 8 and a discharge member 9 for the cooling water 7 made of, for example, a pipe are provided on the upper surface 4a of the cover 4, and the lower end 8a of the supply member 8 is located near the bottom surface 4b of the cover 4. . The terminals 5 and 6 are electrically connected to the output terminals of the high frequency generator 10, and the supply member 8 and the discharge member 9 are connected to the cooler 11 by hoses or the like. The upper surface 4a of the cover 4 and the connecting portion of the supply member 8, the discharge member 9 and the like are sealed, so that the inside of the cover 4 is substantially sealed.

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 in the work 12 which is a material to be heated, the high frequency generator 10 is operated, and a high frequency current of, for example, 100 KHZ (kilohertz) is supplied to the coil 3. . Further, at the same time as 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, and the eddy current generated by the magnetic flux heats and quenches the inner surface of the hole 12a of the work 12. 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 high frequency current supplied to the coil 3 causes the coil 3 and the core 2 to generate heat, but the cooling water 7 supplied from the supply member 8 suppresses this heat generation. At that time, the coil 3 and the like are cooled by the flow of the cooling water 7 generated in the cover 4 from below to above. 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 portion within the cover 4, and is heated while cooling the coil 3 and the like. The cooling water whose weight has become lighter rises in the cover 4 and is returned from the discharge member 9 to the cooler 11. As a result, the flow of the cooling water 7 is generated and does not stay in the cover 4. When the predetermined 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 work is completed.

As described above, according to the above-described embodiment, the coil 3 is wound around the rod-shaped core 2, the coil 3 is housed in the cover 4, and the work 1 2 is cooled while cooling the core 2 and the coil 3 with the cooling water. Since the quenching is performed, the diameter t (see FIG. 1) of the coil device 1 can be reduced. For example, even with a small hole 12a having an inner diameter of 10 mm or less, the inner surface of the coil 12 can be induction hardened. In particular, even at a high frequency of 100 KHZ or 200 KHZ, the core 3 and the like are not deteriorated, quenching can be performed with a high frequency current, and high-precision surface treatment which has been impossible in the past can be performed. Further, the coil device 1 can be manufactured only by winding the coil 3 made of copper wire or the like around the core 2 and storing the coil 3 in the cover 4, so that the manufacturing work thereof is extremely simple. Furthermore, since the cooling water 7 circulates in the cover 4 and the cooling water 7 does not stay in the cover 4, the coil 3 and the like can be effectively cooled. As a result, the diameter of the core 2 and the like can be reduced, and the coil device 1 can be further downsized.

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, and for example, a semi-circular recess. Good. Further, in the above-mentioned embodiment, the cover 4 is formed in a cylindrical shape, but the cover 4 may be formed in an appropriate shape depending on the shape of the inner surface of the work 12 to be quenched. 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 cold cooling water is ejected from the ejection holes, and the flow of the cooling water 7 in the cover 4 is controlled. For this reason, it goes without saying that various modifications can be made without departing from the gist of the present invention, such as providing a partition plate on the inner wall of the cover 4.

[0010]

[Effect of device]

 As described in detail above, according to the coil device for high frequency induction heating of the present invention, the coil device itself can be downsized, and for example, high frequency induction heating of the inner surface of a work having a small diameter can be performed, resulting in high accuracy. The surface treatment can be performed and the coil device can be easily manufactured. Further, it is possible to effectively suppress heat generation of the coil and the like, and it is possible to further reduce the size of the coil device.

[Brief description of 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.

[Explanation of symbols]

 1: Coil device 2: Core 3: Coil 4: Cover 7: Cooling water 8: Supply member 9: Ejection member 10: High frequency generator 11: Cooler 12: Work piece

Claims (2)

[Scope of utility model registration request] 1. A cover comprising: a rod-shaped core; a coil wound around the core to supply a high-frequency current; and a non-conductive cover that houses the coil and the core in a substantially sealed state. A coil device for high frequency induction heating, characterized in that a cooling water supply port and a cooling water supply port are provided in the cover, and cooling water is supplied from the supply port into the cover to cool the core and the coil. 2. The coil device for high frequency induction heating according to claim 1, wherein the supply port is located below the discharge port.