JP3395336B2 - Strip levitation support device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a strip levitation supporting device for non-contact supporting and conveying a strip such as a metal strip in a continuous heat treatment furnace in a levitation state.

[0002]

2. Description of the Related Art In order to prevent the occurrence of scratches when a strip such as a metal strip conveyed in a continuous annealing furnace comes into contact with a roll in the furnace, a strip is formed from a plenum chamber provided in the furnace. It has been conventionally known as a method of transporting a strip that the gas is blown toward the lower surface of the strip to float and support the strip by the gas pressure to support the strip in a non-contact manner.

In order to prevent the strip from colliding with the furnace wall by shifting in the width direction during traveling, for example, JP-A-61-261.
As shown in FIG. 8, the levitating and transporting method disclosed in Japanese Patent No. 440 forms a flat plate portion b horizontally on the upper surface of the plenum chamber a facing the lower surface of the strip plate c, and the flat plate portion b travels in the strip plate traveling direction. A pair of slit-shaped jets d, d opened along the width direction of the strip c are formed at the front and rear edges, and gas is blown obliquely upward inward from the jets d, d to form an upper surface of the flat plate portion b. A static pressure region is formed between the bottom surface of the strip c and the opening widths of the jet ports d, d are wider at both end portions d ′ than in the center of the strip c. A large amount of gas is blown out from the portion d ′ to automatically correct the widthwise displacement of the strip c, that is, a self-centering function is provided.

The levitation device disclosed in Japanese Patent Laid-Open No. 61-201738 has a large number of plenum chambers a provided above and below the strip c as shown in FIG. Of the nozzles e, e, e ... inclined toward the center of the traveling line of the strip plate c, thereby giving a directivity toward the center to the strip plate c by the blown gas pressure and having a centering function. It was.

[0005]

By the way, as described above, the slit-shaped fumaroles d, d whose opening widths are partially different from each other are described.
In the device having the above, there is a problem in that a sufficient static pressure cannot be obtained because the width of the gas curtain formed by the fumes is not uniform.

Further, since the inclined nozzles e, e, e ... Are inclined uniformly toward the center, the directivity in the central direction is always uniformly exerted on the lower surface of the strip c. However, there is a problem in that the belt c moves on the left and right even if the belt c is on the center line to make the running unstable.

[0007]

SUMMARY OF THE INVENTION The strip levitation support device of the present invention is intended to solve the above-mentioned problems. A flat plate portion facing the bottom surface of the strip is formed on the upper surface of the plenum chamber, and the flat plate portion is formed. A pair of slit-like fumaroles that are open along the width direction of the strip at the front and rear edges in the running direction of the strip so that the gas blows diagonally upward inward toward the flat plate portion. At the same time, a gas outlet is opened in the flat plate portion so that the opening ratio gradually increases from the center line toward both sides.

Further, in the strip levitation support device of the present invention, a horizontal flat plate portion is formed on the upper surface of the plenum chamber so as to face the lower surface of the strip plate, and the width of the strip plate is formed at the front and rear edges of the flat plate portion in the strip running direction. A pair of slits of the same width, which are opened along the direction, are formed so that the gas blows obliquely upward and inward toward the flat plate portion, and the flat plate portion approaches both sides from the center line. A feature of the present invention is that the gas outlet is opened by inclining the blown gas toward the center line so that the tilt angle gradually increases.

Further, in the strip levitation support device of the present invention, a horizontal flat plate portion is formed on the upper surface of the plenum chamber so as to face the lower surface of the strip plate, and the width of the strip plate is formed at the front and rear edges of the flat plate portion in the strip running direction. A pair of slits of the same width, which are opened along the direction, are formed so that the gas blows obliquely upward and inward toward the flat plate portion, and the flat plate portion approaches both sides from the center line. It is characterized in that the opening ratio is gradually increased, and the gas outlet is opened so that the angle of inclination of the blown gas toward the center line is gradually increased.

[0010]

With a pair of slits having the same width, the static pressure region can be surely formed on the flat plate portion and the strip plate can be stably supported. Centering action is achieved.

[0011]

Embodiments of the present invention will now be described with reference to the drawings.
In the embodiment shown in FIGS. 1 to 3, the flat plate portion 3 facing the lower surface of the strip 2 is horizontally formed on the upper surface of the plenum chamber 1,
At the front and rear edges of the flat plate portion 3 in the traveling direction of the strip plate, a pair of slit-shaped jet nozzles 4 and 4 having the same width are provided along the widthwise direction of the flat plate portion 3, and gas is directed obliquely upward inward toward the flat plate portion 3. So that a static pressure region is formed between the upper surface of the flat plate portion 3 and the lower surface of the strip plate 2 as shown in FIG. At the same time, a large number of gas outlets 5, 5, 5 ... Are formed in the flat plate portion 3 so that the intervals become closer as the center line 6 approaches both sides as shown in FIG. Then, hot air of non-oxidizing gas, reducing gas, etc., which has been pressure-fed into the plenum chamber 1 from a blower (not shown) through the blow-in port 7 is blown out from the blower ports 4, 4 and the gas blow-out ports 5, 5, 5. The band plate 2 is floated and supported to run in the direction of the arrow.

As described above, the gas outlets 5, 5, 5 ... Are densely opened toward both sides to gradually increase the opening ratio so that the amount of gas from the inside of the plenum chamber 1 increases as the sides approach both sides. As a result of blowing out, when the strip 2 is displaced in the width direction as indicated by the chain double-dashed line in FIG. 3, more gas is blown to the lower surface of the strip 2 on the displaced side, and the levitation force is increased. The strip 2 is tilted with. Therefore, a correction force for returning to the center acts due to the weight of the strip plate 2. This correction force becomes larger as the shift becomes larger, because more gas is blown to the shift side.

In the above embodiment, the gas outlets 5, 5, 5 ... Are arranged on the flat plate portion 3 on the V-shaped line so that the gas curtain is formed in a multi-layered form, and the static gas pressure difference between the inside and the outside of the gas curtain is reduced. It is easy to obtain.

On the other hand, in the embodiment shown in FIG. 4, as the center line 6 of the flat plate portion 3 is approached to both sides, the gas outlets 5, 5, 5, ... Of large diameter are gradually opened to increase the opening ratio. It was made to become.

Further, in the embodiment shown in FIG. 5, the flat plate portion 3 has slit-shaped gas outlets 5, 5 along the traveling direction of the strip plate 2.
The distance between 5, 5 ... is gradually increased as they get closer to both sides.

As illustrated in these figures, the opening ratio can be gradually increased on both sides by changing the size of the gas outlet or the opening density, and the gas outlet amount can be increased on both sides. Since the amount can be increased as it approaches, it is possible to increase the levitation force of the strip 2 as the strip 2 shifts and to provide self-centering property.

On the other hand, in the embodiment shown in FIG. 6, as the flat plate portion 3 approaches the both sides from the center line 6, the blown gas
A short pipe-shaped gas outlet 5, which is inclined in the flat plate portion 3, so that the inclination angle in the direction of the center line gradually increases.
5, 5, ... Are provided. That is, in this strip supporting device, the gas is blown out almost directly from the gas outlet near the center line 6, and the gas is blown out inclining inwardly up to about 45 degrees on both sides. The inclination angle is gradually changed according to the opening position.

For this reason, as the strip plate 2 shifts in the width direction, a large inward pushing-back force acts on the lower surface so that the strip plate 2 can be centered.

In the embodiment shown in FIG. 7, as in the embodiment shown in FIG. 6, the gas outlets 5, 5, 5 ...
5, 5 ... are gradually increased in diameter as they approach both sides to increase both the gas outlet inclination angle and the gas outlet amount. By thus using both means together, the centering action can be further effectively exerted. Can be expected.

[0020]

As described above, the strip plate levitation support device of the present invention is provided with a pair of slit-shaped jet nozzles of the same width so that the strip plate can be stably levitationally supported by static pressure, and a shift occurs in the width direction. However, there is a beneficial effect that the deviation is corrected by the gas blown out from the gas blowout port formed in the flat plate portion and that a stable traveling state is always obtained.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a strip levitation support device of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG.

FIG. 4 is a plan view of a strip levitation support device showing another embodiment of the present invention.

FIG. 5 is a plan view of a strip levitation support device showing another embodiment of the present invention.

FIG. 6 is a cross-sectional view of a strip levitation support device showing another embodiment of the present invention.

FIG. 7 is a cross-sectional view of a strip levitation support device showing another embodiment of the present invention.

FIG. 8 is a perspective view of a conventional strip levitation support device.

FIG. 9 is a cross-sectional view of a conventional strip levitation support device.

[Explanation of symbols]

1 Plenum chamber 2 strips 3 Flat plate part 4 fumaroles 5 gas outlets 6 Center line

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Claims (3)

(57) [Claims] 1. A horizontal flat plate portion is formed on the upper surface of the plenum chamber so as to face the lower surface of the strip plate, and a pair of the same flat plate portions are formed at front and rear edges of the flat plate portion in the strip plate running direction along the width direction of the strip plate. The width slit-shaped fumaroles are opened so that the gas blows obliquely upward and inward toward the flat plate portion, respectively, and the opening ratio is gradually increased as the flat plate portion approaches both sides from the center line. A strip levitation support device characterized by having a gas outlet. 2. A flat plate portion that is opposed to the lower surface of the strip plate is formed on the upper surface of the plenum chamber, and a pair of the same flat plate portions are formed at the front and rear edges of the flat plate portion in the traveling direction of the strip plate along the width direction of the strip plate. width slit jet ports with gas to open so blown obliquely on inwardly directed onto each plate portion, the outlet gas gets closer from the center line on both sides in the flat plate portion Sen
A strip levitation support device, characterized in that a gas outlet is opened by inclining it so that the inclination angle in the tarline direction is gradually increased. 3. A horizontal flat plate portion is formed on the upper surface of the plenum chamber so as to face the lower surface of the strip plate, and a pair of the same flat plate portions are formed at the front and rear edges of the flat plate portion in the strip running direction along the width direction of the strip plate. The width slit-shaped fumaroles are opened so that the gas blows obliquely upward inward toward the flat plate portion, and the opening ratio gradually increases toward the flat plate portion from the center line to both sides, and A strip levitation support device characterized in that a gas outlet is opened by inclining the blown gas toward the center line so that the angle of inclination is gradually increased.