JP3180177B2 - Electric heating device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric heating device for heating a metal strip made of iron, aluminum, copper or the like by passing an electric current thereto, and more particularly to a stable electric heating while preventing the metal strip from meandering. The present invention relates to an electric heating device.

[0002]

2. Description of the Related Art Conventionally, when a metal strip is continuously annealed, the heating and keeping of the temperature are mostly performed by radiation by gas heating or indirect heating by an electric heater. However, since these heating methods indirectly heat the material to be heated, there is a problem that rapid heating cannot be performed, and when the sheet thickness or the sheet width changes, the productivity is greatly restricted.

In order to solve this problem, it has been proposed to employ energization heating. For example, JP-A-61-82
No. 954 discloses that a steel sheet is directly energized through a current-carrying roll to raise the temperature of the steel sheet itself as a heating element.
JP-A-1-142032 and JP-A-1-18778
Japanese Patent Publication No. 9 describes that a metal strip is heated before and after a metal strip passing through an annular transformer to heat the metal strip.

Japanese Patent Application Laid-Open No. 61-82954 discloses a method of winding a metal strip around an energizing roll, and Japanese Patent Application Laid-Open No. 1-142032 discloses a method of clamping a metal strip between rolls. ing. Generally, a method in which a metal strip is sandwiched between energizing rolls and energized,
A method is employed in which a metal strip is wound around a current-carrying roll to energize.

[0005] In this way, the method in which a current is directly applied to a metal strip and heated by Joule heat has a higher heating capacity per unit time than indirect heating of gas or electricity, and the production accompanying a change in the sheet thickness or the sheet width. It is excellent in that it can solve the problem of reduced properties and can make the equipment compact.

However, when the metal strip is heated using the energizing rolls, when the metal strips meander, the meandering metal strips are pressed by the energizing rolls and the holding rolls to pass the metal strips. There is a problem that it becomes easier. To solve this problem, Japanese Patent Application Laid-Open No. 5-103287 describes that the position of a metal strip is corrected before the metal strip is bitten by an energizing roll.

[0007]

However, it has been found that it is sometimes impossible to correct meandering only by correcting the position of the metal strip before biting the metal strip. That is,
If the cause of the meandering of the metal strip is poor shape of the original sheet, that is, a defective rolling shape or poor winding, etc., it is often possible to stably energize by correcting the meandering of the metal strip in front of the low-temperature side energizing roll. In addition, meandering may occur in the area past the high-temperature side energizing roll or the high-temperature side energizing roll, and it has been found that such meandering causes more damage to the product and the energizing roll. In other words, when heated to a high temperature, the strength of the metal strip decreases and the shape tends to collapse, and when the metal strip having the collapsed shape is pressed down, the metal strip breaks and overlaps, and excessive local stress acts on the overlapping portion. In this case, the energizing roll is damaged.

The cause of the meandering of the metal strip after passing through the high-temperature side energizing roll portion or the high-temperature side energizing roll is that the metal strip is provided after the high-temperature heated metal strip or after the high-temperature side energizing roll. It is conceivable that the transport rolls or the like take away heat and expand and deform, or that the current-carrying rolls wear during use and the rolling balance is lost.

Therefore, the present invention provides an electric heating device for energizing and heating a metal strip using an energizing roll.
Provided is an energization heating device capable of detecting meandering of a traveling metal strip and controlling the meandering so that the metal strip always keeps a constant relationship with the energizing roll.

[0010]

SUMMARY OF THE INVENTION The present invention provides an electric heating apparatus comprising: a moving metal strip;
While the metal strip passes through the low-temperature side energizing roll and passes through the high-temperature side energizing roll while being held between the energizing rolls by the holding rolls, a current flows between the low-temperature side energizing roll and the high-temperature side energizing roll, In an electric heating device that heats the plate, an edge detection device that detects an edge position of the metal strip running between the low-temperature energizing roll and the high-temperature energizing roll,
An electric heating device characterized in that at least one of the low-temperature energizing roll and the high-temperature energizing roll has a roll moving device that can freely move the energizing roll itself.
It is a place.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0012]

FIG. 1 is a side view showing an example of an electric heating device according to the present invention. The metal strip 1 is sandwiched between the low-temperature energizing roll 2 by the low-temperature pressing roll 7 and the high-temperature energizing roll 15 by the high-temperature pressing roll 23.
Current from both conductive rolls 2,15 is passed between 2,15 and heated by Joule heat generation during the movement from the low temperature side conductive rolls 2 to the high temperature side conductive rolls 15.

The low-temperature side energizing roll 2 receives a roll shaft 3 by a roll bearing 4 and is fixed to an energizing stand 12 via a base 5. A roll chock 9 connected to a hydraulic pressure, pneumatic, electric, etc. pressure reduction cylinder 10 moves on a slide mechanism 11 by expansion and contraction of the pressure reduction cylinder 10. The low-temperature holding roll 7 passes the roll strip 8 through the roll shaft 8 to reduce the metal strip 1 that travels by the expansion and contraction of the reduction cylinder 10.
It can be opened.

The high-temperature side energizing roll 15 is also fixed to the energizing stand 19 via the base 18 similarly to the low-temperature side energizing roll 2. The roll chock 21 connected to the pressure reduction cylinder 24 for hydraulic pressure, air, electric power, or the like moves on the slide mechanism 22 by expansion and contraction of the pressure reduction cylinder 24. The high-temperature side holding roll 23 passes through the roll chock 21 through the roll shaft 20, and the metal strip 1 running by the expansion and contraction of the reduction cylinder 24.
Can be released.

Although not shown, an energizing brush is attached to the roll shaft 3 of the low-temperature side energizing roll 2, and is connected to a power source 30 through a conductive member 31 such as a copper plate. In the high-temperature side energizing roll 15, similarly, an energizing brush attached to the roll shaft 16 is connected to a power supply 30 by a conductive member 31.

Thus, the power supply 30 and the energizing roll 2
15 are connected, the low-temperature side energizing roll 2, the metal strip 1, the high-temperature side energizing roll 15, the conductive member 31, and the power source 3
0, the conductive member 31, and the closed circuit of the low-temperature side energizing roll 2 are configured, and the running metal strip 1 generates Joule heat by the applied current.

Although not shown, the energizing rolls 2, 1
5. The energizing stands 12 and 19 are grounded on either the high temperature side or the low temperature side, and the energizing stand on the non-ground side is installed on the floor via an insulator so that current does not flow between the energizing rolls. By providing a choke coil, it is possible to prevent a stray current from flowing on the line.

An edge detecting device is provided between the energizing rolls to detect whether or not the traveling metal strip 1 has meandering. That is,
The light emitted from the light projector 13 is received by the light receiver 14 having a line sensor or the like, and the meandering is detected by detecting the position where the metal strip 1 blocks.

Information on the detected edge position of the metal strip 1 is sent to the control device 26 through the cable 25, and the amount of movement of the cylinder of the roll moving device 28 is adjusted so that the edge position of the metal strip 1 is always constant. To control the energizing stand 1
9. The position of the energizing roll 15 is controlled.

FIG. 2 is a top view for explaining the principle of correcting the meandering of the metal strip 1.

When there is no meandering, the metal strip 1 travels at the edge positions 32 and 33 with respect to the energizing rolls 36 and 38. However, it is assumed that meandering occurs for some reason and the metal strip 1 meanders in the direction of the edge positions 34 and 35. When such meandering occurs, wrinkles 37 are formed. Originally, when there was no meandering, the contact positions a, b, c and d between the energizing rolls 36 and 38 and the edge of the metal strip 1 were as shown in FIG. 2, and the diagonal distances ad and diagonal of the contact portions Distance b
-C will be approximately equal. However, when the metal strip 1 meanders for some reason, and the contact portions a ', b', c, and d between the energizing rolls 36, 38 and the edge of the metal strip 1 become as shown in FIG. a'-d and diagonal distance b'-
c is different, and in the case of the example shown in FIG.
c becomes longer.

When such meandering occurs, the energizing roll 39 is inclined as shown by a dotted line in FIG. 2 so that the diagonal distances a'-d and b'-c of the contact portions are substantially equal. good. The moving method includes moving the energizing stand 19 back and forth in the traveling direction of the metal strip 1 as described above, moving the base of the energizing roll up and down using a hydraulic device, an electric cylinder, an air cylinder, or the like, It is also possible to use a method such as moving the object. In this embodiment, the roll moving device 28 is provided on the high-temperature side energizing stand 19, but may be provided on the low-temperature side energizing stand 12 or on both stands.

[0023]

[0024]

[0025]

[0026]

According to the electric heating device of the present invention, the positional relationship between the metal strip and the electric roll can be kept constant, and the electric current can be stably supplied. In addition, since uneven tension distribution is less likely to be generated on the metal strip, wrinkles and breaks can be prevented from occurring, and the operation can be performed without damaging the product. The wrinkles and breaks of the metal strip exert local stress on the rolls and cause damage to the rolls.However, since the wrinkles and breaks of the metal strips can be prevented, the rolls can be prevented from being damaged. Minimize downtime and roll replacement costs.

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of an electric heating device according to the present invention.

FIG. 2 is a top view for explaining occurrence of meandering of a metal strip in an energizing roll section .

[Explanation of symbols]

REFERENCE SIGNS LIST 1 metal strip 2 low-temperature side energizing roll 3 roll shaft 4 roll bearing 5 base 6 energizing stand base 7 low-temperature side holding roll 8 roll shaft 9 roll chock 10 pressure-reducing cylinder 11 slide mechanism 12 energizing stand 13 light emitter 14 receiver 15 high-temperature side energizing roll DESCRIPTION OF SYMBOLS 16 Roll axis | shaft 17 Roll bearing 18 Base 19 Power supply stand 20 Roll axis 21 Roll chock 22 Slide mechanism 23 High-temperature side press roll 24 Reduction cylinder 25 Cable 26 Control device 27 Cable 28 Roll moving device 29 Power supply stand base 30 Power supply 31 Conductive member 32 Edge position 33 edge position 34 the edge position 35 edge position 36 the low temperature side conductive rolls 37 wrinkles 38 hot side conductive rolls 39 hot-side conducting roll a contact position b contact position c contact position d contact position

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-6-145815 (JP, A) JP-A-6-87015 (JP, A) JP-A-4-124223 (JP, A) JP-A-5-124 331555 (JP, A) JP-A-3-226529 (JP, A) JP-A-5-23483 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) C21D 1 / 40,9 / 52 C21D 9 / 56,9 / 62 C22F 1 / 04,1 / 08 H05B 3/00

Claims (1)

(57) [Claims] 1. A running metal strip is rolled on a low-temperature side
While holding each holding roll between
Therefore, while the metal strip passes through the high-temperature side energizing roll via the low-temperature side energizing roll, an electric current is passed between the low-temperature side energizing roll and the high-temperature side energizing roll to heat the metal strip, An edge detection device that detects the edge position of the metal strip running between the low-temperature side energizing roll and the high-temperature side energizing roll, and the energizing roll itself can be freely attached to at least one of the low-temperature side energizing roll and the high-temperature side energizing roll. An electric heating device comprising a roll moving device capable of moving .