JPS6342482Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention has an upper surface plate portion and a lower surface plate portion, and a disc-shaped member is inserted between these parts, and the disc-shaped member is heated by high-frequency induction action. Regarding the high frequency coil according to the present invention, it is particularly suitable for application to a high frequency coil used for hardening processing.

FIG. 1 shows a conventional high-frequency coil 1 of this type. The high-frequency coil 1 has a pair of coil lead parts 2 and 3 facing each other, and a pair of coil lead parts 2 and 3 facing each other and having a substantially semicircular plate shape. Each has an upper surface plate portion 4 and a lower surface plate portion 5. In addition, in FIG. 1, 6 is a disk-shaped member to be subjected to high-frequency induction heating. When this disk-shaped member 6 is subjected to high-frequency induction heating, for example, the center hole 7 of this member 6
The member 6 is held by a holding jig (not shown), and approximately half of the member 6 is inserted between the upper plate part 4 and the lower plate part 5 of the high-frequency coil 1, and the disc-shaped member 6 is held by a holding jig (not shown). It was driven to rotate, and at the same time a high frequency large current was caused to flow in the direction of arrow A in FIG.

However, when performing high-frequency induction heating on the disc-shaped member 6 using such a conventional high-frequency coil 1,
As the heating temperature of the member 6 increases, due to its own weight and residual stress, the member 6 is plastically deformed into an umbrella shape from the central hole 7 toward the outer peripheral edge 6a, as shown by the two-dot chain line in FIG. . In order to improve heating efficiency, when the gap l between the upper plate part 4 and lower plate part 5 of the high-frequency coil 1 and the disc-shaped member 6 is configured to be small, the outer peripheral edge 6a of the disc-shaped member 6 came into contact with the lower plate portion 5 of the high-frequency coil 1 and generated sparks between them, and as a result, there was a high possibility that the disk-shaped member 6 and the high-frequency coil 1 would be melted and damaged.

For this reason, in the past, the gap l (see FIG. 2) between the high-frequency coil 1 and the disc-shaped member 6 was set relatively large, and the disc-shaped member 6 was heated during high-frequency induction heating.
Contact with the high frequency coil 1 due to plastic deformation of the coil 1 is prevented. However, if the gap l is increased, the heating efficiency will be greatly reduced, and excessive electric power will be required, which is very uneconomical.

Further, the fact that the disc-shaped member 6 deforms sequentially as the heating progresses means that the gap 1 changes sequentially, so that the heating of the disc-shaped member 6 becomes uneven, and the entire part cannot be heated uniformly. It was very difficult to obtain a product with uniform hardening characteristics.

The present invention was devised in view of the above-mentioned actual situation, and the purpose of the present invention is to ensure mutual contact during high-frequency induction heating even if the gap between the high-frequency coil and the disc-shaped member is reduced. It is an object of the present invention to provide a high-frequency coil that can prevent the above-mentioned problems from occurring and perform high-frequency induction heating of the entire disc-shaped member uniformly and with high heating efficiency.

The present invention is characterized by a high-frequency coil having an upper plate part and a lower plate part, a disc-shaped member inserted between these parts, and heating the disc-shaped member by high-frequency induction action. In order to prevent plastic deformation of the disc-shaped member due to high-frequency induction heating, a plurality of protrusions made of a non-conductive member are provided on the lower plate portion.

Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 3 to 5.

This embodiment relates to a high-frequency coil used for heating and hardening a disc spring member, which is a component of an automobile clutch.

First, FIG. 3 shows a disc spring material 10 as a disc-shaped member, and this disc spring material 10 has a diameter of, for example, 2 mm.
It is made by punching and forming a thin steel plate of about 100 mL, and has a central hole 11 and a plurality of radial holes 12, respectively.

Further, FIG. 4 shows the high frequency coil 13. This high-frequency coil 13 includes a pair of coil lead parts 14 and 15 facing each other, and a semi-disc-shaped part 16 having a size and shape into which approximately half of the disc spring material 10 can be inserted, This semi-disc-shaped portion 16 has a pair of upper surface plate portions 17 and lower surface plate portions 18 which are arranged parallel to each other and facing each other,
It is composed of a pair of left and right side plate parts 19 and 20. Note that semicircular notches 21 and 22 are formed in the center portions of the upper surface plate portion 17 and the lower surface plate portion 18, respectively, so as to correspond to the central hole 11 portion of the disc spring material 10.

Further, in order to prevent plastic deformation of the disc spring material 10 due to heating and to prevent contact with the high frequency coil 13, the lower plate portion 18 of the high frequency coil 13 is made of a non-conductive material such as a ceramic material such as silicon nitride. A plurality of cylindrical projections 23 are provided. The plurality of protrusions 23 are disposed so as to correspond to the outer peripheral edge 10a of the disc spring material 10, and their upper end surfaces 23a are disposed on substantially the same plane.

Next, when heating the disc spring material 10 with the high frequency coil 13 configured as described above, first,
As shown in FIG. 5, the disc spring material 10 is
It is placed and fixed on 4. Thereafter, the disk spring material 10 is moved together with the holding jig 24 by a moving device (not shown), and the high frequency coil 1 is moved as shown in FIG.
Approximately half of it is inserted between the upper surface plate portion 17 and the projection 23 of the lower surface plate portion 18 of No. 3. Under this condition, the disc spring material 10 is rotationally driven together with the holding jig 24 by a drive device (not shown).

At the same time, a high frequency large current is supplied to the high frequency coil 13 from the high frequency power supply 25, and the high frequency large current is passed through the high frequency coil 13 in the direction of arrow A in FIG. Note that the high frequency power source 25 is selected in a frequency range of 30 KHz to 400 KHz depending on the wall thickness of the disc spring material 10. As a result, the disc spring material 10 is heated by the high frequency induction effect.

At this time, since the wall thickness of the disc spring material 10 is relatively thin, as the heating temperature rises, the wall thickness of the disc spring material 10 is increased from the central hole 11 of the disc spring material 10 to the outer peripheral edge 10a as shown by the two-dot chain line in FIG. It begins to transform into an umbrella shape. However, the lower plate portion 1 of the high frequency coil 13
Due to the presence of a plurality of protrusions 23 arranged on 8,
The outer peripheral edge 10a of the disc spring material 10 is rotated and heated while being received by the upper end surfaces 23a of the plurality of projections 23. Therefore,
The amount of plastic deformation of the disc spring material 10 is determined by the amount of plastic deformation of the disc spring material 10
Since the degree of deformation is suppressed according to the length of the deformation, the degree of deformation is suppressed to a small extent, and each part of the disc spring material 10 is uniformly heated as a whole to a required heating temperature. In addition, since the plastic deformation of the disc spring material 10 does not proceed beyond the protrusion 23, the outer peripheral edge 10a of the disc spring material 10 does not come into contact with the lower plate portion 18 of the high frequency coil 13 and sparks are not generated between them. .

In this manner, when the disc spring material 10 reaches the required heating temperature, the supply of the high frequency large current is cut off, and the heat treatment process is completed. Thereafter, the disc spring material 10 is molded into a disc shape in a molding heat treatment step (not shown) and is quenched.

Although one embodiment of the present invention has been described above, the present invention is not limited to the embodiment described above, and various modifications and changes can be made based on the technical idea of the present invention.

For example, in addition to the disc spring material 10 described above, examples of disc-shaped members include disc brakes, which are parts for motorcycles, and the high-frequency coil of the present invention is used to heat the disc brakes during hardening treatment. If used, the same effects as described above can be achieved.

As described above, in the present invention, a plurality of protrusions made of a non-conductive material are provided on the top plate of the high-frequency coil. It is possible to suppress plastic deformation at a certain time to a predetermined amount, and it is possible to reliably prevent melting and damage caused by contact with the high-frequency coil. Moreover, uneven heating caused by excessive plastic deformation of the disc-shaped member can be prevented, and high-frequency induction heating can be uniformly applied to each part of the entire disc-shaped member.

Furthermore, as mentioned above, since contact between the high-frequency coil and the disc-shaped member can be reliably prevented, the distance between the upper and lower plate parts of the high-frequency coil and the disc-shaped member during heating can be reduced. In this way, efficient heating can be performed.

[Brief explanation of the drawing]

1 and 2 are for explaining a conventional high-frequency coil, in which FIG. 1 is a perspective view of the high-frequency coil, FIG. 2 is a sectional view taken along the line - in FIG. 1, and FIGS. Figure 5 is for explaining the high-frequency coil of the present invention, in which Figure 3 is a plan view of the disc spring material, Figure 4 is a perspective view of the high-frequency coil, and Figure 5 is a perspective view of the high-frequency coil.
The figure is a sectional view taken along the - line in FIG. 4. 10... Belleville spring material as a disc-shaped member, 13...
High frequency coil, 17...Top plate portion, 18...Bottom plate portion, 23...Protrusion, 23a...Top end surface, 25...High frequency power supply.

Claims (1)

[Scope of utility model registration request] A high-frequency coil having an upper surface plate portion and a lower surface plate portion, a disk-like member inserted between these and heating the disk-like member by high-frequency induction action. A high frequency coil characterized in that a plurality of protrusions made of a non-conductive material are provided on the lower surface plate part in order to prevent plastic deformation of the disc-shaped member.