JPH0342031Y2 - - Google Patents

Description

[Detailed explanation of the idea]

a. Field of Industrial Application The present invention relates to an improvement of a high-frequency induction heating coil, and particularly to a high-frequency induction heating coil suitable for use in surface heating and quenching of the top and side portions of rails. b. Prior Art Conventionally, a coil shown in FIG. 4 has been used as this type of high-frequency induction heating coil. In FIG. 4, a high frequency induction heating coil 100
is composed of nine linear coil pieces connected in series, and each coil piece is connected to other coil pieces almost perpendicularly to each other to form each side of a rectangular parallelepiped. Three parietal surface heating coil pieces 101a, 101b, 10 arranged on the upper surface of this rectangular parallelepiped
1c is located on a plane facing parallel to the top surface of the rail in order to heat the top surface of the rail. Additionally, a pair of coil pieces 102 are arranged on the lower surface of this rectangular parallelepiped.
a and 102b face each other in parallel with both side surfaces along the longitudinal direction of the rail in order to heat the side surfaces of the rail head. This head side heating coil piece 10
2a, 102b are four connected coil pieces 103
a, 103b, 103c, 103d, the above-mentioned parietal surface heating coil pieces 101a, 101b,
101c. Further, the two parietal surface heating coil pieces 101b and 101c have the same length, and have terminals 105a and 105b connected to the high frequency power source 104 at one end. When heating the top and side parts of the rail using this high-frequency induction heating coil 100, the rail top surface is aligned with the plane formed by the coil piece 101a and the coil piece 101b (or 101c). are parallel to each other at a predetermined interval, and both side surfaces of the rail are connected to four connected coil pieces 10.
3a, 103b, 103c, and 103d, the rail and the coil 100 are held by a holder (not shown) so as to be opposed to each other at a predetermined interval, and the rail is made to run relatively. c. Problems to be solved by the invention In the conventional high-frequency induction heating coil 100 described above, a pair of coil parts 102a and 102b arranged on the lower surface of a rectangular parallelepiped and these coil parts 10
2a, 102b and four coil pieces 103a, 103b, 103c, 103d connected vertically face the head side of the rail. On the other hand, three coil pieces 101a, 101b, and 101c disposed on the upper surface of this rectangular parallelepiped face the top surface of the head. Therefore, when heating the rail by passing a high-frequency current through the coil 100, due to the difference in length of the coil parts on the opposing sides,
The density of eddy currents generated on the side of the head of the rail is larger than that on the top of the head, so the rate of temperature rise on the side of the head is greater than that on the top of the head.When the top of the head reaches a predetermined temperature, the side of the head will overheat or It becomes molten. In the coil 100 described above, by conducting heat from the side of the head to the top of the head, the heating temperature of both parts is made uniform. Therefore, by making the clearance (the distance between the coil and the heating material) on the side of the head larger than that on the top of the head, the heating efficiency of the side of the head is lower than that of the top of the head, and at the same time, it is possible to accommodate the longitudinal direction of the rail. It was necessary to increase the length of the coil and increase the heating time of the rail. However, even if the above measures are taken, it is difficult to equalize the heating temperature between the top of the head and the side of the head, and there is also the problem that increasing the clearance on the side of the head increases power consumption. Ta. In the top of the rail that has been surface hardened using the coil 100, the thickness of the hardened layer is thinner and the fatigue strength is lowered. On the other hand, since the head side portion becomes hotter than necessary, there is a risk of quench cracking, and there is also a risk of material deterioration due to coarsening of the quenched structure. The present invention was devised in view of the problems of the prior art described above, and its purpose is to provide a high-frequency induction heating coil that enables uniform heating of the top and side parts of the rail and has a short longitudinal length. It is about providing. d Means for Solving the Problems The present invention for solving the above problems provides a high-frequency induction heating coil for high-frequency induction heating the head of a rail that is relatively moved in the longitudinal direction. (b) a pair of mutually parallel parietal surface heating coil parts arranged correspondingly on the parietal surface along the longitudinal direction of the rail; (b) a pair of mutually parallel heads arranged correspondingly on both coronal side surfaces along the longitudinal direction of the rail; (c) a coil section correspondingly arranged along the widthwise center of the top surface of the rail and extending parallel to the head side heating coil section; It consists of a pair of coil pieces each connected to both ends and extending parallel to the parietal heating coil section, and on a plane including the parietal heating coil section, the parietal heating coil section and the head surface. (d) a connecting coil portion connecting each of the coil portions in series; and (d) a connecting coil portion connecting each of the coil portions in series. do. e Effect Among the cross-connected coil parts arranged to cross the rail top surface, the coil pieces arranged parallel to the longitudinal direction contribute to heating near the widthwise central portion of the rail top surface. Furthermore, the two coil pieces disposed perpendicularly to the same direction eliminate unevenness in heating temperature that occurs in the width direction. A coil construction method in which the coil parts constituting the same coil section are connected perpendicularly to each other is the most effective method for uniformizing the composite magnetic field generated by the current flowing through each coil part. f Example Hereinafter, a preferred example of the high frequency induction heating coil according to the present invention will be described in detail based on the accompanying drawings. FIG. 1 is a perspective view showing the configuration of a high-frequency induction heating coil (hereinafter simply referred to as a coil) 1;
FIG. 2 is a perspective view showing how this coil 1 is used. The coil 1 includes a top surface heating coil section 2 consisting of a pair of mutually parallel coil sections 2a and 2b arranged along the width direction of the rail S so as to correspond to the top surface A thereof. At both ends of the coil piece 2a, there are two coil pieces 3a of equal length extending vertically downward with respect to the coil piece 2a.
3b are connected to each other at one end. Also,
At both ends of the coil piece 2b, there are two coil pieces 3c and 3d of equal length, similar to the coil piece 2a.
are connected to each other at one end. At the other end of each of the coil pieces 3a, 3b, there are two coil pieces 4a, 4b extending perpendicularly to the coil pieces 3a, 3b in the longitudinal direction of the rail.
are connected to each other at one end. Also, one end of each of two coil pieces 4c, 4d extending in the longitudinal direction of the rail is connected to the other ends of the coil pieces 3c, 3d, respectively. has been done. By this, 4
The book coil parts 4a, 4b, 4c, 4d serve as a pair of cranial side heating coil parts 4 on both cranial sides _B1 , _B2.
parallel and opposite. The lengths of the coil portion 4a and the coil portion 4d are approximately equal, and the lengths of the coil portion 4b and the coil portion 4c are also approximately equal. One end of each of two coil pieces 3e, 3f having the same length and extending vertically upward with respect to the coil pieces 4a, 4b is connected to each other end of the coil pieces 4a, 4b. There is. Furthermore, one end of each of two coil pieces 3g and 3h, which extend vertically upward and have the same length, is connected to each other end of the coil pieces 4c and 4d, respectively. ing. Two coil portions of equal length are provided on a plane including the parietal surface heating coil portion 2 and within a region surrounded by the parietal surface heating coil portion 2 and the cranial side heating coil portion 3. Pieces 5a, 5b are arranged parallel to coil piece 2a. One end of each of these coil pieces 5a, 5b is connected to the top surface A of the rail S.
are connected to each other via coil pieces 5c that are arranged correspondingly along the widthwise center of the head side heating coil portion 4 and extend parallel to the head side heating coil portion 4. The other ends of the coil pieces 5a and 5b are connected to the other ends of the coil pieces 3e and 3h, respectively. That is, the coil pieces 5a, 5b, 5c are attached to the parietal surface A.
The coil parts 3a, 3b, 3c, 3d, 3
e, 3h are both heating coil parts 2, 4 on the parietal surface and the cranial side surface.
It constitutes a connecting coil section 3 that connects these in series. At the other end of each of the coil pieces 3f and 3g, two coil pieces 2c of equal length are disposed on a plane including the parietal surface heating coil part 2 and parallel to the coil part 2. , 2d are connected to each other. Further, at each other end of the coil pieces 2c, 2d, two coil pieces 2e, 2f of equal length are arranged on the plane and parallel to the coil piece 5c. One end is connected.
High frequency power supply connection terminals 6a, 6b are provided at the other ends of the coil pieces 2e, 2f. As described above, between these terminals 6a and 6b, a coil 1 is constructed in which each of the coil parts is connected in series, and the coil 1 is relatively moved in the longitudinal direction of the rail, and the head of the rail is heated by high frequency induction. It is formed. The high frequency induction heating coil 1 shown in this example is as follows:
The dimensions shown in the table below are preferred.

[Table] Unit: mm
In particular, when the length of each coil section is set so that l ₁ /(L ₁ +L ₂ )=0.3 to 0.5, the heating balance between the top surface and the side surface of the head becomes better. Note that, as shown in FIG. 3, two sets of transversal connection coil parts 5 may be arranged between the parietal surface heating coil parts 2, 2. In this case, the coil pieces 4b and 4c are connected by the coil pieces 3u, 3v, and 3w, and the coil pieces 4d and 4e are connected by the coil pieces 3x, 3y, and 3z, respectively. However, these coil parts constitute the connecting coil part 3 similarly to the coil parts 3a...3h. Terminal 6 of the high frequency induction heating coil 1 of the above embodiment
When a high frequency power source 7 is connected to a and 6b, a large current flows in the direction of the arrow as shown in FIG. At this time,
Current flows in the same direction through the four coil pieces 5a, 5b, 2c, and 2d arranged parallel to the width direction of the rail at the center of the top surface, and the coil pieces 5a, 5b, 2c, and 2d arranged parallel to the longitudinal direction of the rail. Currents in the same direction also flow in the book coil parts 5c, 2e, and 2f. Therefore, heating of the top of the head is effectively strengthened. The rail S and the coil 1 are held by a holder (not shown), so that the rail S passes through the inside of the coil 1 while keeping a predetermined distance therebetween. The heat-treated portion passing through the inside of the coil 1 is sent to the next step, and the surface hardening treatment is completed by spraying cooling water or the like. Although the embodiments of the present invention have been described above, the application of the high frequency induction heating coil according to the present invention is not limited to heat treatment of rails, but can also be applied to flat metal materials. It is possible. g. Effects As described above, the high-frequency induction heating coil 1 for the rail head according to the present invention has the transverse connection coil portion 5 provided between the pair of top surface heating coil portions 2. In addition to the heating effect of the pair of parietal surface heating coil sections 2, the transversally connected coil section 5 also greatly contributes to the heating of the parietal surface. Therefore, the synergistic effect of both coil parts makes it possible to efficiently heat the parietal surface, which was difficult to heat with conventional coils. It is possible to eliminate the non-uniformity of heating temperature. Therefore, even if the dimensions of the cranial side heating coil section 4 are shortened, the problem of non-uniform heating temperature does not occur.

[Brief explanation of drawings]

Figures 1 and 2 show an embodiment of the high-frequency induction heating coil for the rail head according to the present invention, Figure 1 is a perspective view showing the circuit configuration of the coil, and Figure 2 is the use of the coil. It is a perspective view showing an aspect. FIG. 3 is a perspective view showing the circuit configuration of the coil in another embodiment of the present invention. FIG. 4 is a perspective view showing a circuit configuration of a conventional high-frequency induction heating coil for a rail head. 1...High frequency induction heating coil, 2...Parietal surface heating coil section, 3...Connection coil section, 4...Cranial side heating coil section, 5...Transverse connection coil section, 6......
High frequency power supply connection terminal, 7... High frequency power supply, 10
0... High frequency induction heating coil, 101... Parietal surface heating coil piece, 102... Head side heating equal piece, 103... Connection coil piece, 104... High frequency power supply, 105... High frequency power supply connection terminal .

Claims (1)

[Claims for Utility Model Registration] In a high-frequency induction heating coil for high-frequency induction heating the head of a rail that is relatively moved in the longitudinal direction, (a) mutually arranged coils corresponding to the top surface of the rail along the width direction thereof; (b) a pair of mutually parallel cranial side heating coil portions arranged correspondingly on both cranial side surfaces along the longitudinal direction of the rail; (c) a parietal surface of the rail; Coil pieces arranged correspondingly along the central point in the width direction of the surface and extending parallel to the head side heating coil part, and connected to both ends of the coil piece, respectively, and the parietal side heating coil part at least on a plane including the parietal heating coil part and in an area surrounded by the parietal heating coil part and the cranial side heating coil part. A high-frequency induction heating coil for a rail, comprising: a transverse connecting coil section disposed at one location; and (d) a connecting coil section connecting each of the coil sections in series.