JPH08306475A - Induction heating device - Google Patents

Abstract

PURPOSE: To improve heating efficiency by forming an interval between upper and lower inductors of a C-shaped inductor as a variable structure, preventing collision of an end part of a warped heating object material, and narrowing a gap between the heating object material and the inductors. CONSTITUTION: In an induction heating device where a heating coil is respectively wound round upper and lower iron core leg parts sandwiching an opening part of an iron core 9 combined in a C shape, and upper and lower inductors 5a and 5b are formed, and a heating object material 6 is made to travel between these, and induction heating is performed, the iron core 9 combined in a C shape is constituted so as to be separated into upper and lower iron cores 8a and 8b. Hinge parts 11a and 11b on which rotary shafts 10a and 10b are installed are formed in separated parts, and gears 17a and 17b mutually meshing with the rotary shafts 10a and 10b are respectively installed, and a jack 19 is installed on this upper gear 17a through an arm 18, and the upper and lower inductors 5a and 5b are rotated in the reverse direction, and an interval is adjusted.

Description

Detailed Description of the Invention

The present invention relates to a C-shaped inductor for inductively heating a belt-shaped material to be continuously conveyed, and an improved mechanism for adjusting the interval between the upper and lower inductors.

[0002]

2. Description of the Related Art Generally, in a steel rolling line or the like, a process of heating a strip-shaped material to be heated (sheet bar) to a predetermined temperature in advance, continuously running it, and then rolling it by a rolling mill to form a thin plate. Then, there is a problem that the temperature of the end side of the heated material gradually drops. In this way, if the end side temperature drops and the whole temperature is unevenly rolled, the quality is not constant,
Since the hardness of the end side becomes high and the material to be heated is cracked and the rollers of the rolling mill are worn, there are problems such as heating the end of the material to be heated on the upstream side of the rolling mill of the steel rolling line. An induction heating device is installed.

In this conventional induction heating device, an iron core is C
There is a C-shaped inductor formed in a shape. As shown in FIG. 8, this C-shaped inductor 1 has upper and lower inductors in which heating coils 4 and 4 are respectively wound around upper and lower iron core legs 2a and 2b sandwiching an opening 3 of a C-shaped iron core 2 combined. 5a,
5b is formed. This C-shaped inductor 1,
Band-shaped materials to be heated 6 which are arranged so as to face each other and are conveyed.
Both ends of the above are passed through the opening 3 for induction heating.

The C-shaped inductor 1 has a smaller leakage magnetic flux and a better heating efficiency as the space between the upper and lower inductors 5a and 5b is narrow, but it is necessary to cope with the change in the plate width of the material 6 to be heated, and the temperature is in the range of a few thousand degrees. In order to protect the insulation of the heating coil 4 from the radiant heat of the heated material 6 which is also heated, there is a limit to narrowing the interval. Moreover, since the front end and the rear end of the material to be heated 6 along the longitudinal direction are warped, the warped end may collide with the heating coil 4 and be damaged. The rolling line must be stopped and repaired, and in consideration of these, the upper and lower inductors 5
Since the space between a and 5b is formed wide, the heating efficiency could not be improved.

[0005]

SUMMARY OF THE INVENTION The present invention eliminates the above-mentioned drawbacks and makes the interval between the upper and lower inductors of the C-shaped inductor variable so as to prevent the warped end of the heated material from colliding with the heated material. The present invention provides an induction heating device in which the inductor gap is narrowed to improve heating efficiency.

[0006]

The induction heating device according to claim 1 of the present invention is such that a heating coil is wound around upper and lower iron core legs sandwiching an opening of an iron core combined in a C shape and upper and lower inductors are respectively wound. In an induction heating device that forms a sheet and runs induction heating between the upper and lower inductors,
The iron core combined in the C-shape is separated into upper and lower iron cores, and a hinge portion having a rotating shaft attached is formed in the separated portion to adjust the interval between the upper and lower inductors. To do. Further, the invention according to claim 2 is characterized in that the iron core cross-sectional area in the vicinity of a hinge portion that rotatably supports the iron core is locally enlarged.

An induction heating apparatus according to a third aspect of the present invention has a conducting means attached to the rotating shaft and meshing with each other, and a biasing means for biasing the conducting means, and the upper and lower inductors are arranged in opposite directions. It is characterized by being rotated.
Further, the invention according to claim 4 is characterized in that a gear is used as the transmission means, and the diameter of the gear attached to the upper rotating shaft is smaller than the diameter of the gear attached to the lower rotating shaft. It is a thing.

[0008]

In the induction heating device according to claim 1 of the present invention, C
The iron cores combined in the shape of a letter are separated into upper and lower iron cores,
Form a hinge part with a rotating shaft attached to the separated part,
Since the spacing between the upper and lower inductors is adjusted, the spacing between the upper and lower inductors can be adjusted according to the plate thickness of the material to be heated, and efficient heating can be achieved. Further, since the front end and the rear end side of the material to be heated are warped, when this portion travels, it is possible to avoid the collision with the material to be heated by abruptly moving up the upper inductor and retracting it.

In the induction heating apparatus according to the second aspect, the iron core cross-sectional area in the vicinity of the hinge portion that rotatably supports the iron core is locally enlarged. Therefore, when the interval between the upper and lower inductors is widened, Since the iron core has a large cross-sectional area in the hinge portion and the magnetic flux passage cannot be narrowed, the loss here can be reduced.

In the induction heating device according to the third aspect of the present invention, the arm is rotated by driving the jack or the cylinder according to the change in the plate thickness of the material to be heated, and the upper rotation shaft connected to the arm is rotated. It moves and the upper inductor rotates. A gear is attached to the upper rotating shaft, and the lower gear meshing with the upper rotating shaft also rotates in the opposite direction, and the lower inductor connected to this lower rotating shaft rotates in the opposite direction to keep the gap between the openings. Can be adjusted. Further, in the induction heating device according to claim 4, since the diameter of the gear attached to the upper rotary shaft is smaller than the diameter of the gear attached to the lower rotary shaft, the upper inductor is arranged according to the gear ratio. Can be made larger than the lower inductor.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to FIG. This C-shaped inductor 1 forms an iron core 9 in which the U-shaped iron cores 8a and 8b are combined in a C-shape, fixes the lower U-shaped iron core 8b, and fixes the upper U-shaped iron core 8a. A hinge portion 11 having a rotating shaft 10 attached thereto is formed in the separated portion, and upper and lower iron core leg portions 2 sandwiching an opening portion 3 are formed.
Heating coils 4 and 4 are respectively wound around a and 2b to form upper and lower inductors 5a and 5b. Further, in the hinge portion 11, the end portion of the upper U-shaped iron core 8a has a rotating shaft 10.
Is formed, and a semicircular concave portion 13 is formed at the end of the lower U-shaped iron core 8b that slides with the semicircular portion 12.
Are formed.

In this structure, the upper U-shaped iron core 8a
Is rotatably supported by the hinge portion 11, so that the interval between the upper and lower inductors 5a and 5b can be adjusted according to the plate thickness of the material 6 to be heated, so that efficient heating can be achieved. Further, since the front end and the rear end side of the material to be heated 6 are warped, this is detected by a warp amount detector (not shown) provided on the rolling line, and the upper U-shaped portion is detected based on a signal corresponding to the warp amount. If the iron core 8a is rapidly raised and retracted, it is possible to avoid collision with the heated material 6. Therefore, the upper and lower inductors 5a,
It is not necessary to set the interval b, and in the normal state, the operation is performed according to the plate thickness of the material 6 to be heated, so that heating can be performed efficiently. The lower inductor 5b does not need to be retracted because the center apron is arranged to prevent the tip of the heated material 6 from dropping downward.

FIG. 2 shows another embodiment of the present invention.
If the width of the horizontal portion of the upper U-shaped iron core 8a is A,
The width of the vertical portion where the hinge portion 11 is formed is thickened to A + α. When the width of the horizontal portion of the lower U-shaped iron core 8b is A, the width of the vertical portion where the hinge portion 11 is formed is thickened to A + α. The semicircular recess 13 formed at the end of the vertical portion is formed so that the opening 3 side thereof largely projects upward and overlaps the upper semicircular portion 12. The other structure is the same as that of FIG.

In this structure, the upper U-shaped iron core 8a
As indicated by a phantom line, the iron core cross-sectional area in the hinge portion 11 is large even when the hinge portion 11 is rotated and retracted, and the overlapping width when rotated is kept larger than A and the passage of the magnetic flux is narrowed. Since it is not there, the loss here can be reduced.

FIG. 3 shows another embodiment of the present invention.
If the width of the horizontal portion of the upper U-shaped iron core 8a is A,
A structure in which the width of the upper portion of the vertical portion where the hinge portion 11 is formed is A, and the lower portion is formed with a circular portion 14 having a diameter A + α centering on the rotation axis 10 and the iron core cross-sectional area of the hinge portion 11 is locally enlarged. Has become. Further, the width of the horizontal portion of the lower U-shaped iron core 8b is A, the width of the lower portion of the vertical portion where the hinge portion 11 is formed is A, and the width of the upper portion is thicker to A + α. The formed semi-circular concave portion 13 is formed so that the opening 3 side thereof largely projects upward and overlaps the upper circular portion 14.

Also in this structure, as shown by the phantom line in the upper U-shaped iron core 8a, even when the iron core 8a is rotated upward and retracted, the iron core cross-sectional area in the hinge portion 11 is wide, and the overlap occurs when rotated. Since the width is kept larger than A and the magnetic flux passage is not narrowed, the loss can be reduced.

4 and 5 show another embodiment of the present invention. In the drawings, 16 is a dolly, in which an upper U-shaped iron core 8a, an intermediate drum-shaped fixed iron core 8c and a lower portion are provided. An iron core 9 combined with a C-shape is attached by the U-shaped iron core 8b. A rotary shaft 10a is attached to a portion of the upper U-shaped iron core 8a separated from the intermediate fixed iron core 8c, and a semicircular portion 12 centered on the rotary shaft 10a is formed at this end portion. A semi-circular recess 13 is formed in the upper portion of the fixed iron core 8c that slides with the hinge core 11a. Similarly, a rotating shaft 10b is attached to a portion of the lower U-shaped iron core 8b separated from the fixed iron core 8c, and the rotating shaft 10b is attached to this end.
A semi-circular portion 12 centered on 10b is formed, and a semi-circular concave portion 13 is formed in the lower portion of the fixed iron core 8c that slides with the semi-circular portion 12 to form a hinge portion 11b.

A rotating shaft 10a attached to the side surface of the upper U-shaped iron core 8a is supported by penetrating the side surface of the carriage 16 as shown in FIG. 5, and a gear 17a is attached to the penetrating rotating shaft 10a. Has been. Similarly, a rotating shaft 10b attached to the side surface of the lower U-shaped iron core 8b is also supported by penetrating the side surface of the carriage 16, and a gear 17b is attached to the penetrating rotating shaft 10b.
It meshes with the gear 17a having the same diameter as this. Further, one end of an arm 18 is connected to the rotating shaft 10a to which the gear 17a is attached, and the other end is connected to a jack 19 as shown in FIG.

When the material to be heated 6 is heated by the induction heating device having the above structure, the arm 18 is rotated by driving the jack 19 according to the change of the plate thickness, and the rotating shaft 10a connected to the arm 18 is rotated. Rotates, and the upper inductor 5a rotates. A gear 17a is attached to the rotating shaft 10a, and a gear 17b meshing with the rotating shaft 10a is rotated in the opposite direction. The lower inductor 5b connected to the rotating shaft 10b is rotated and the gap between the openings 3 is increased. It can be adjusted greatly.

In this case, when the upper U-shaped iron core 8a tries to descend by its own weight, the lower U-shaped iron core 8a
Therefore, if the weights of the iron cores 8a and 8b are the same and the diameters of the gears 17a and 17b are the same, the weights of the two can be balanced. Therefore, only a small force is applied to the jack 19, and the upper and lower inductors 5a and 5b can be easily rotated without the counterweight by driving the motor with a small capacity. Therefore, when the warped portion on the front end or the rear end side of the heated material 6 passes, the upper and lower inductors 5a and 5b are pivoted so as to open largely by pushing down the arm 18 with the jack 19. Can be evacuated.

FIGS. 6 and 7 show another embodiment of the present invention in which a gear mounted on the upper rotary shaft 10a.
The diameter of 17a is the same as that of the gear 17 attached to the lower rotary shaft 10b.
It is designed to be smaller than the diameter of b.
b is formed in a fan shape to have a large gear diameter,
The teeth are formed only on the circumference. Further, since the load applied to the jack 19 increases in accordance with the gear ratio, it is preferable to extend the horizontal portion 20 on the upper U-shaped iron core 8a and attach the weight 21 there to balance.

In the induction heating device having the above structure, the upper gear
Since the diameter of 17a is smaller than the diameter of the lower gear 17b, the turning distance of the upper inductor 5a can be made larger than the turning distance of the lower inductor 5b according to the gear ratio. This is effective when the distance between the running surface of the material to be heated 6 and the floor is small and the material cannot be largely rotated downward. Since the material 6 to be heated is conveyed on the table roller, there is no problem in the downward warp of the material 6 to be heated, and since the upward warp is large, the upper inductor 5a pivots largely upward. Need to be evacuated.

In the above embodiment, the case where the jack 19 is used as the biasing means for rotating the arm 18 has been described, but a cylinder may be used.

[0024]

As described above, in the induction heating device according to the first aspect of the present invention, the interval between the upper and lower inductors constituting the C-shaped inductor is made variable to prevent the warped end of the heated material from colliding. In addition, the heating efficiency can be improved by narrowing the gap between the material to be heated and the inductor. Further, in the induction heating device according to the second aspect, when the interval between the upper and lower inductors is widened, the iron core cross-sectional area in the hinge portion is wide and the passage of the magnetic flux cannot be narrowed, so that the loss here can be reduced.

Further, in the induction heating apparatus according to the third aspect of the present invention, since the upper and lower inductors are rotatably connected to each other via the upper and lower gears, the upper and lower inductors are rotated in the opposite directions, so that the openings are spaced apart. It can be adjusted greatly. Further, since the upper and lower gears are meshed with each other, the weight of the upper and lower inductors can be balanced, and a jack or cylinder having a small capacity can be easily driven. Further, in the induction heating device according to the present invention, the diameter of the gear attached to the upper rotary shaft is smaller than the diameter of the gear attached to the lower rotary shaft. Is effective when the rotation distance of the lower inductor can be made larger than the rotation distance of the lower inductor and the distance between the running surface of the material to be heated and the floor is narrow and the material cannot be largely rotated downward.

[Brief description of drawings]

FIG. 1 is a front view showing an induction heating device for a movable inductor according to an embodiment of the present invention.

FIG. 2 is a front view showing an induction heating device for a movable inductor according to another embodiment of the present invention.

FIG. 3 is a front view showing an induction heating device for a movable inductor according to another embodiment of the present invention.

FIG. 4 is a front view showing an induction heating device in which upper and lower inductors are connected by upper and lower gears according to another embodiment of the present invention.

5 is a vertical cross-sectional view of the induction heating device shown in FIG.

FIG. 6 is a front view showing an induction heating device connected by upper and lower gears having different diameters according to another embodiment of the present invention.

7 is a vertical cross-sectional view of the induction heating device shown in FIG.

FIG. 8 is a front view showing a conventional induction heating device.

[Description of sign]

 1 C-type inductor 2 C-type iron core 2a Iron core leg 3 Opening 4 Heating coil 5a Upper inductor 5b Lower inductor 6 Heated material 8a Upper C-shaped iron core 8b Lower C-shaped iron core 9 C-shaped combination Iron core 10 Rotating shaft 11 Hinge part 12 Semi-circular part 13 Semi-circular concave part 17a Gear 17b Gear 18 Arm 19 Jack 20 Weight

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tetsuji Toizaki 1-1-1, Shibaura, Minato-ku, Tokyo Inside Toshiba Head Office

Claims (4)

[Claims] 1. A heating coil is wound around upper and lower iron core legs sandwiching an opening of an iron core combined in a C shape to form upper and lower inductors, and a material to be heated is run between the upper and lower inductors. In an induction heating device that performs induction heating, the C-shaped combined iron core is separated into upper and lower iron cores, and a hinge portion with a rotating shaft is formed in the separated portion to adjust the interval between the upper and lower inductors. An induction heating device characterized in that 2. The induction heating apparatus according to claim 1, wherein the iron core cross-sectional area in the vicinity of a hinge portion that rotatably supports the iron core is locally enlarged. 3. A transmission means, which is attached to a rotary shaft and meshes with each other, and a biasing means for biasing the transmission means,
The induction heating device according to claim 1, wherein the upper and lower inductors are rotated in opposite directions. 4. A gear is used as the transmission means, and the diameter of the gear attached to the upper rotary shaft is smaller than the diameter of the gear attached to the lower rotary shaft.
Induction heating device as described.