JPS62107030A - Floating type strip passing device - Google Patents

Abstract

PURPOSE:To provide a floating type strip passing device which can reduce an overaging zone without trouble by constituting the device in such a manner that a belt-like body floated, supported and passed by a gas floating and supporting device is stably run always in the prescribed position by a pair of linear moving magnetic field induction motors. CONSTITUTION:The forces fA, fB acting on a metallic strip 1 are offset by each other and do not move the strip 1 in the transverse direction while the strip 1 travels in the normal passing position. On the other hand, the area of the strip 1 covered by linear motors 10A, 10B changes when the strip 1 moves in the transverse direction by a certain cause. More specifically, the area covered by the linear motor on the side of direction to which the strip moves increases and the area on the opposite side direction decreases. The strip 1 is, therefore, automatically reset to the normal passing position by DELTAf without artificial control at all. In the figure, 4 denotes a floater to support the own weight of the strip by ejecting NH gas to generate pressure between said floater and the trip 1, 5 denotes a supply duct to the floater 4, and M denotes the center line of the strip 1.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a floating plate threading device used in lines that handle strips, such as continuous annealing lines, continuous galvanizing lines, stainless steel annealing lines, and colored iron plate coating lines.

<Prior Art> First, a continuous annealing furnace for cold rolled steel sheets will be described as an example of a line for passing a strip.

The strip fed out from the payoff reel and passed through the cleaning tank and looper is supplied to a continuous annealing furnace shown in FIG. In the furnace shown in the figure, rolls 2 are arranged above and below, and the strip 1 is
Necessary heating and cooling are performed while traveling downward between 1 and 1, and material properties such as predetermined high tensile strength and good deep drawability are achieved at room temperature! Led. More specifically, in order to prevent surface oxidation of the strip 1, the furnace is filled with quantitative HN gas, and the strip 1 is normally heated at 650°C.
Heating with radiant tube 3 to ~750℃
+? , then soaked for several tens of seconds, and further heated to 400
It is rapidly cooled to about .degree. C., subjected to an overaging treatment at about 400.degree. C. for about 2 minutes, and finally rapidly cooled to room temperature.

By the way, in such a continuous annealing furnace, the overaging zone takes a long time of about 2 minutes, so the overaging zone becomes long due to the relationship with the speed of the stroke, especially in the large size 1! , In a single continuous annealing furnace, the overage 4"+F is as long as about 100m, and the furnace as a whole is about 150m ■!Y, which is extremely long. Therefore, if this overage 1i) can be reduced by 10, the furnace will It can be manufactured quickly and reduces the construction cost of the furnace.

It has been found that a specific means for shortening this overaging zone is to change the material composition of the strip and raise the heating temperature of the strip higher than before.

However, in order to realize a furnace with a shortened overaging zone, the strip must be of high temperature, so the hot strip comes into contact with the cold rolls, resulting in uneven contact and problems in the rolling oil. The problem is deformation of the strip due to non-uniform cooling in the width direction of the strip due to contact with the non-uniform roll surface on which carbon or the like is adhered.

Furthermore, if the strip is run vertically in the vertical direction, a creep phenomenon occurs due to the strip eyeballs, resulting in a failure to form a product. For this reason, the strip needs to run horizontally and stably.・ Due to the above problem, in order to prevent the hot strip from coming into contact with the roll and also to prevent the strip from running in the vertical direction,
As shown in FIG. 8, floaters (gas flotation support devices) 4 are arranged in the furnace below or on both the upper and lower sides of the strip.
It is better to float the strip and run it horizontally. In Figure 8, the metal strip 1 runs from left to right in the figure, and radian I. A tube 4 is a floater which supports the hair of the strip by spouting HN gas to generate pressure between it and the strip, 5 is a gas duct for supplying the floater 4, and 6 is a furnace wall. The floater 4 has a cross-sectional structure shown in FIG. 9, and the 70-meter 4 communicating with the gas duct 5 has a slit 9 at the HN gas jet port, and the HN gas jetted from the slit 9 has a flow direction. The sudden change in the interlocking amount causes pressure to be generated between the strip 1 and the strip 1.

(Problems to be Solved by the Invention) As mentioned above, in order to shorten the overaging zone, the heating temperature of the strip is increased, and furthermore, in order to eliminate the adverse effects of this high heating temperature, the floaters are arranged horizontally. 8. However, in the floater shown in FIG. 8, although a force is generated in the northward direction (in the direction of gravity) of the strip 1, no force is generated in the width direction of the strip, so that the strip does not move in the width direction. If the strip deviates, it cannot be returned to the normal pass line.In other words, there is no centering function.Therefore, if the strip deviates while it is being fed, there is a greater possibility that the strip will come into contact with the furnace wall, and eventually Needs centering function.

In view of the above problems, the present invention aims to provide a floating plate threading device having a centering function.

<Means for Solving the Problems> The floating plate threading device of the present invention includes a gas levitation support device for ejecting gas and suspending and supporting the strip by ejecting gas, and a threading device for the strip. The present invention is characterized in that it includes a pair of linearly moving magnetic field type induction motors that are arranged symmetrically with respect to the plate direction and generate moving magnetic fields in opposing directions.

(Function) If the strip is threaded along the regular pass line,
This strip is subjected to opposing and equal forces caused by the moving magnetic field and maintains this path line. −・
On the other hand, if the strip deviates from the regular pass line,
The force acting from the direction of deviation of the two-shaped body becomes larger than the other force, pushing the band-shaped body back to the side opposite to the deviation and returning to the normal path line.

<Example> An example of the present invention will be described with reference to FIGS. 1 to 6. Incidentally, the same parts as the conventional ones are given the same reference numerals.

As shown in the first factor, the floating plate threading device has a floater 4 having a slit 9 formed therein and communicating with the gas duct 5.
A gas levitation support device ε consisting of:

Eleven pairs of linearly moving magnetic field type induction motors (hereinafter referred to as linear motors) are arranged below the strip 1 symmetrically with respect to the threading direction of the metal strip 1 supported in levitation by the floater 4. IOA, 108.

Linear motors IOA and IOB are both shown in Figures 2 and 3.
As shown in the figure, a yoke 12 having several teeth 12a and made of a magnetic metal material, and a plurality of coils 11 wound around the peaks 12a and connected to an AC power source (not shown)
It consists of linear motors 1OA and 10B.
generate moving magnetic fields of equal magnitude in mutually opposing directions.

The driving principles of these linear motors IOA and 10B are not particularly different from those known in the past, and there are various driving methods depending on the number of current phases and the number of poles (number of N and S poles). It is not limited to any particular method. Here, the most typical two-pole three-phase system will be explained.

In FIGS. 3 and 4, A, B, and C in the drawings indicate coils 11 corresponding to three phases, respectively, and A', B',
The coils 11 of C' are wound around the yoke 12 in the opposite direction to the coils 11 of A, B, and C, respectively. These A, B, C
, A'.

When currents IA, IB, IC, and I whose phases are shifted by %π are applied to the coils B' and C' +1, IB+ and Ic- are applied to the teeth 12a around which the respective coils 11 are wound. A magnetic field proportional to the current is generated.

IA, IAI-Iosln O The graph shown with a solid line in Fig. 4 is the cage of yoke 12 (
It represents the X-direction intensity component of the magnetic field generated at the position (Y-direction), and is for the case where the current phase is 0=0. The shape of this magnetic field is that since the linear motors IOA and 10B have two poles, one N pole and one S pole are generated.
It is in the form of a sine wave, and when the current phase 0 changes from 0 to 2π in a certain period, the sine wave of the magnetic field also advances in phase in accordance with the change (X direction in Figure 4). ), and the graph shown by the dotted line in FIG. 4 is for the case where the current phase is 0=%π. The magnetic field generated above the yoke 12 and moving linearly in this way
The following force is applied to the conductor placed above 2. In other words, when a moving magnetic field crosses a conductor, an eddy current is generated inside the conductor according to Maxwell's law of induced magnetic field, and the interaction between this eddy current and the magnetic field causes the conductor to move in the same direction as the moving magnetic field. The so-called Lorentz force is generated.

The linear motors IOA and 10B are arranged symmetrically with respect to the centerline M (passing direction) of the metal string 1, which is a conductor, with a gap below the strip 1, and the linear motors IOA and 10B , IOB
The strength of the moving magnetic fields generated in each of the strips is set to be equal, and the moving directions thereof are set to be opposite to each other from the width direction of the strip 1, as shown by the arrows in FIG. Therefore,
As shown in FIGS. 514 and 6, the metal slip I and lip L, which are at the normal threading position where the center line M is in the center between the linear motors IOA and 108, are exposed to the moving magnetic field of the linear motors IOA and IOB, respectively. Force f A+ f
8. are openings facing each other from the width direction of the strip l,
It acts on the magnitude of two times.

(pass line), strip 1
The forces fA and fB acting on the strip 1 cancel each other out and do not move the strip 1 in one width direction. On the other hand, if the metal strip 1 moves (meanders) in one width direction for some reason, the linear motors IOA, IQ
The area of the strip 1 covered by B changes, that is, the area covered by the linear motor increases in the direction of movement, and decreases in the opposite direction. The forces fA and fs acting on the metal strip 1 increase and decrease in proportion to the area of the strip 1 covered by the linear motors IOA and 10B.
For example, when strip 1 moves toward the linear motor IOA, f A > f B and Δf = fA - f
A force B acts on the strip 1 in a direction opposite to its direction of movement. Therefore, without any artificial control.

The metal strip 1 is automatically returned to the normal threading position by the force Δf. Note that this restoring force must be adjusted depending on the thickness of the strip 1, the running distance, etc., but this is due to the current applied to the near motor.
': 43 Mountain Lu Shu r Merinia Mo Yu's k, bottle size, etc. can be easily implemented.

The number of pairs of linear motors to be provided is determined as appropriate, and the position of the linear motors may be freely set not only below the strip 1, but also above or above the strip 1 as appropriate. I can do it. Further, in the above embodiment, the linear motor is disposed at an intermediate position of the floater 4, but it can also be disposed by being incorporated into the floater 4.

<Effects of the Invention> According to the floating plate threading device of the present invention, the strip-shaped body that is floated and supported by the gas levitation support device and threaded can always be stably run at a predetermined position. Therefore, when the present invention is applied to a continuous annealing furnace, the overaging zone can be shortened without any problem, and the manufacturing period and construction cost of the furnace can be shortened.

[Brief explanation of drawings]

1 to 6 relate to one embodiment of the present invention, FIG. 1 is a perspective view of a floating plate threading device, FIG. 2 is a plan view of a beam near motor, and FIG. 3 is a ■A sectional view in the direction of arrows, Figure 4 is an explanatory diagram of the operation of the beam near motor, Figure 5 is a plan view of the beam near motor part of the floating plate threading device, and Figure 6 is Vl-VI in Figure 5.
7 is a schematic configuration diagram of a continuous annealing furnace, FIG. 8 is a sectional view of an over-aging furnace, and FIG. 9 is a sectional view of a floater. In the drawing. ■ is the metal strip, 4 is the floater, 10A, IOB beam near motor, and M is the center line of the metal strip.

Claims (1)

[Claims] A gas levitation support device that ejects gas to levitate and support a strip-shaped object to be threaded by the gas pressure; and magnetic fields disposed symmetrically with respect to the threading direction of the strip-shaped object and moving in directions facing each other. A floating sheet threading device characterized by comprising a pair of linearly moving magnetic field type induction motors that generate.