EP0216656B1 - Guiding device for band material, in particular for a metal strip treatment installation - Google Patents

Abstract

Guidance device for material traveling in strip form, especially for a sheet metal treatment plant, which includes a guidance roller (13) over which the strip (20) passes. This roller is carried by a movable structure (10) itself mounted on a fixed structure (1), so as to be capable of oscillating around an axis (Y-Y) contained in a median plane at right angles to the axis (X-X) of the roller, tangent to this roller and forming an angle of between 5 DEG and 30 DEG with the upstream length (21) of the strip.

Description

The present invention relates to guide devices for strip materials, as well as their applications.

In installations for treating an elastoplastic product in the form of a strip and, in particular, in installations for treating strips of hot or cold rolled sheets, it is necessary to use devices for guiding these strips. This is particularly the case in heat treatment furnaces and in accumulators which are generally arranged at the inlet and / or at the outlet of treatment installations.

Such a guide device generally comprises a guide roller mounted to rotate about its axis on a movable frame, itself supported by a fixed frame, actuating and retaining members being provided for moving and holding the movable frame by compared to the fixed frame.

In a first known arrangement, the movable frame supporting the guide roller is mounted so as to be able to oscillate about an axis which can be defined as the intersection of a median plane perpendicular to the axis of the roller with a plane containing the upstream strand of the strip. If the strip moves in a vertical plane, the axis of oscillation of the movable frame and consequently of the guide roller, is then found to be vertical, tangent to the roller and contained in the median plane of the latter. Such an arrangement has a major drawback which lies in too long a reaction time, since it is necessary to move the movable frame and therefore the guide roller over a large amplitude in order to obtain a correction on the strip and a reminder of the latter in centered position. In addition, the correction has no effect on the upstream strand and the regulation of such a device is difficult taking into account this large amplitude of displacement.

US Pat. No. 3,109,572 proposes another arrangement in which the movable frame is supported relative to the fixed frame so as to be able to oscillate around an axis also contained in the median plane perpendicular to the axis of the roller but s' extending perpendicular to the plane of the strip, at a certain distance below the axis of the roll. In such an arrangement, if the strip moves in a vertical plane the axis of rotation is therefore horizontal, whereas it was vertical in the first device described.

The response time of this second device is much shorter, but in return, it has another drawback which consists in an elongation and a deformation of the strip at its edges, this drawback being particularly serious in the case of thin sheets. , that is to say sheets having a thickness less than about 0.4 mm.

In addition, this known device results in limiting the speed of the strips to a value which cannot exceed 25 m / nm; still it should be specified that this upper limit is reached only if a manual control is added to the conventional automatic control device.

The object of this invention is therefore to provide a guide device for elastoplastic web materials, which does not have any of the drawbacks stated above and which, therefore, offers a sufficiently short response time without causing deformation. inadmissible material passing through the device.

To this end, the subject of the invention is a device for guiding a strip of elastoplastic material, comprising a guide roller mounted to rotate about its axis on a movable frame, itself supported by a fixed frame, means of actuation and holding being provided to move and maintain the movable frame by approaching the fixed frame, the frame being mounted oscillating around an axis contained in a median plane perpendicular to the axis of the guide roller, device in accordance with that described in US-A 3,109,572, characterized in that said movable frame is mounted oscillating about the axis on at least one bearing surface of the fixed frame and on at least one cylindrical guide surface centered on the axis, said axis being at least approximately tangent to the roller and forming with one and / or the other strand of the strip an angle of between 5 and 30 _° .

• - l'axe d'oscillation est tangent au rouleau au voisinage du brin amont de la bande;
• - le bâti fixe délimite un plan incliné sur l'horizontale et comporte des moyens d'appui et de guidage coopérant avec des moyens complémentaires portés par le bâti mobile;
• - les moyens d'appui et de guidage et les moyens complémentaires portés par le bâti mobile comprennent trois sous-ensembles comportant chacun au moins un couple de surfaces d'appui et un couple de surfaces de guidage;
• - le rouleau est porté par un bâti sur un bâti intermédiaire de façon à pouvoir osciller par rapport à ce bâti intermédiaire autour d'un axe contenu dans un plan médian, perpendiculaire à l'axe du cylindre, s'étendant perpendiculairement au brin de la bande et situé à une certaine distance au-dessous de l'axe du rouleau, le bâti intermédiaire étant lui-même monté sur le bâti fixe de façon à pouvoir osciller autour d'un axe tel que défini précédemment.
• - des moyens d'immobilisation sont prévus entre le bâti mobile et le bâti intermédiaire, d'une part et entre le bâti intermédiaire et le bâti fixe, d'autre part.

According to other characteristics:

• - The axis of oscillation is tangent to the roller in the vicinity of the upstream strand of the strip;
• - The fixed frame defines an inclined plane on the horizontal and includes support and guide means cooperating with complementary means carried by the movable frame;
• - The support and guide means and the complementary means carried by the movable frame comprise three sub-assemblies each comprising at least a couple of support surfaces and a couple of guide surfaces;
• the roller is carried by a frame on an intermediate frame so as to be able to oscillate relative to this intermediate frame around an axis contained in a median plane, perpendicular to the axis of the cylinder, extending perpendicular to the strand of the strip and located at a certain distance below the axis of the roller, the intermediate frame itself being mounted on the fixed frame so as to be able to oscillate about an axis as defined above.
• - immobilization means are provided between the movable frame and the intermediate frame, on the one hand and between the intermediate frame and the fixed frame, on the other hand.

• - la Fig. 1 est une vue schématique en perspective d'un dispositif de guidage suivant l'invention;
• - la Fig. 2 est un schéma montrant la position de l'axe de rotation ou d'oscillation du rouleau de guidage;
• - la Fig. 3 est une vue en élévation latérale d'un autre mode de réalisation d'un tel dispositif;
• - la Fig. 4 est une vue en coupe prise suivant la ligne 4-4 de la Fig. 3 ; et
• - la Fig. 5 est une vue de droite du dispositif de la Fig. 3.

The invention will be described in more detail below with reference to the attached drawing, which gives only by way of example and in which:

• - Fig. 1 is a schematic perspective view of a guide device according to the invention;
• - Fig. 2 is a diagram showing the position of the axis of rotation or of oscillation of the guide roller;
• - Fig. 3 is a side elevational view of another embodiment of such a device;
• - Fig. 4 is a sectional view taken along line 4-4 of FIG. 3; and
• - Fig. 5 is a right view of the device of FIG. 3.

The guide device shown in the drawings can be placed, for example, in a strip heat treatment oven, or else in an accumulator.

This device as shown in Fig.1 comprises a fixed frame 1 made in any suitable manner and which comprises at its upper part a frame 2 delimiting an inclined plane 3 forming with the horizontal an angle a between 5 and 30 ° and for example around 10 _° in a particular embodiment. On this fixed frame is supported a movable frame 10 also comprising a frame 11 and provided with two bearing supports 12 between which is rotatably mounted a guide roller 13 carried by a shaft 14. This roller is rotatable about its axis XX and can be driven in rotation from a motor 15. On the roller 13 passes a strip 20 whose two upstream 21 and downstream 22 strands are here vertical and that it is a question of maintaining in position centered on the roller.

In the embodiment shown, the movable frame is mounted on the fixed frame so as to be able to oscillate about an axis YY perpendicular to the inclined plane 3 defined by the fixed frame, tangent to the roller 13 on the side of the latter which is attacked by the upstream strand 21 of the strip, and finally contained in the median plane of the roller, perpendicular to the axis XX.

Referring to the diagram in FIG. 2, which is assumed to be contained in the aforementioned median plane of the roller, the position of the axis YY of oscillation of the fixed frame appears clearly. This axis YY therefore forms with the vertical an angle equal to the angle a of inclination of the plane 3, that is to say an angle between 5 and 30 _° and in the example shown close to 10 _° .

In this embodiment, the means for supporting the movable frame on the fixed frame comprise three bearing assemblies 31, 32, 33 of which two 31.32 are arranged at the upper part of the frame 2 and the other 33 at the part lower of this same frame. Each bearing assembly comprises a block 4 secured to the fixed frame and which delimits a support surface 5 and a cylindrical guide surface 6 centered on the axis YY, as well as a foot 40 carried by the movable frame and also delimiting it a bearing surface 41 and a cylindrical guide surface42. These surfaces are made or coated with an appropriate anti-friction material.

In the example shown and as is more clearly visible in FIG. 4, the guide surfaces associated with the lower assembly 33 have a smaller radius than the guide surfaces of the two other bearing assemblies, because they are closer to the axis of oscillation YY.

The device is supplemented by means for actuating and holding the movable frame relative to the fixed frame. These actuating means comprise two jacks 50 arranged on two opposite sides of these frames and which are connected to a control device, known per se, and which will not be described in detail here. This control device comprises means for supplying the cylinders with hydraulic fluid and a control circuit comprising photocells or other sensors of the position of the strip which, as a function of the position of the latter, ensure the supply jacks so as to move the movable frame in a proper direction to return the strip to its centered position.

This result is obtained by oscillating the movable frame around the axis YY, the angular movement between the two extreme positions of the guide roller can be, for example, of the order of 15 _° in a particular application.

In the example shown in the drawing, the axis of oscillation of the movable frame relative to the fixed frame has been shown rigorously tangent to the roller.

Of course, the position of this axis can be slightly offset without significantly modifying the operation of the device. Likewise, the angle which this axis forms with a reference direction which can be the direction of the adjacent strand of the strip to be guided can be chosen in a range between 5 and 30 _° , preferably between 7 and 20 _° , for the applications considered.

• - le déplacement du rouleau de guidage qui est effectué pour ramener la bande en position centrée se traduit par une déformation faible des rives de la bande :
• c'est ainsi que pour un déplacement latéral de la bande de 100 mm, l'allongement en rives pour une bande donnée est de 4 mm, alors qu'avec le deuxième dispositif antérieur décrit en tête de ce mémoire, pour un déplacement latéral de la bande de 100 mm, l'allongement en rives pour une bande donnée était de 16 mm.

The advantages of this arrangement compared to known arrangements are as follows:

• the displacement of the guide roller which is carried out to bring the strip back to the centered position results in a slight deformation of the edges of the strip:
• Thus, for a lateral movement of the strip of 100 mm, the elongation at the edges for a given strip is 4 mm, whereas with the second prior device described at the head of this thesis, for a lateral displacement of the 100 mm strip, the elongation at the edges for a given strip was 16 mm.

The invention therefore makes it possible to divide the elongation on the bank by 4.

• - ce dispositif a un temps de réponse satisfaisant ;
• - il provoque un effet de guidage important dans le brin aval et moyen dans le brin amont, dans la mesure où l'axe d'oscillation du bâti mobile est tangent au rouleau au voisinage de la génératrice de contact entre le brin amont de la bande et le rouleau ; bien entendu, cet effet pourrait être inversé en disposant l'axe d'oscillation du côté du brin aval ou encore partagé entre les deux brins en disposant l'axe d'oscillation entre ces deux positions extrêmes ;
• - il permet d'augmenter sensiblement la vitesse de défilement des bandes : à titre d'exemple, une vitesse de 35 m/mn peut être atteinte sans intervention manuelle, c'est-à-dire simplement en utilisant un dispositif de commande automatique de conception classique. Des vitesses supérieures, par exemple de l'ordre de 45 m/mn, peuvent être envisagées, la limite supérieure de vitesse étant alors imposée par des considérations indépendantes du guidage.

This is particularly important when the strips subjected to this guidance have a very small thickness, for example less than 0.40 mm;

• - this device has a satisfactory response time;
• - It causes a significant guiding effect in the downstream and medium strand in the upstream strand, insofar as the axis of oscillation of the movable frame is tangent to the roller in the vicinity of the contact generator between the upstream strand of the strip and the roller; of course, this effect could be reversed by placing the axis of oscillation on the side of the downstream strand or even shared between the two strands by placing the axis of oscillation between these two extreme positions;
• - it makes it possible to significantly increase the running speed of the strips: for example, a speed of 35 m / min can be reached without manual intervention, that is to say simply by using an automatic control device for classic design. Higher speeds, for example of the order of 45 m / min, can be envisaged, the upper speed limit then being imposed by considerations independent of the guidance.

As a variant of this device, it can be noted that it is possible to combine it with one of the prior devices: this is how in the embodiment shown in FIGS. 3 to 5, the roller is carried by a frame 1OLa mounted relative to an intermediate frame 10b in accordance with the teaching of the second prior device described at the head of this thesis, that is to say oscillating about an axis ZZ horizontal and orthogonal to the XX axis, and located at a certain distance below this XX axis. This intermediate frame 10b is itself mounted on the fixed frame 1 in accordance with the invention. Actuating cylinders 51 are provided to move the frame 10a relative to the frame 10-b, as well as locking devices 52, 53 to selectively secure the frame 10a to the frame 1 0E or else the frame 1 Ob to the frame 1.

Such an arrangement makes it possible to combine the advantages of the two elementary devices.

As a variant, the means for guiding the movable frame relative to the fixed frame may consist of thrust bearings with balls, needles, a crown or any other suitable means.

Claims (8)

1. A device for guiding a strip (20) of elastoplas- tic material comprising a guide roller (13) mounted so as to rotate about its axis (X-X) on a movable structure (10), which is itself supported by a fixed structure (1), actuating and retaining means (50) being provided for moving and retaining the movable structure relative to the fixed structure, said movable structure (10) being pivotally mounted about an axis (Y-Y) contained in a medial plane at right angles to the axis of the guide roller (13), characterized in that said movable structure (10) is mounted so as to be capable of pivoting about the axis (Y-Y) on at least a support surface of said fixed structure (1) and on at least a cylindrical guide surface centred on the axis (Y-Y), said axis (Y-Y) being at least substantially tangent to the roller (13) and forming with one and/or the other side of the strip an angle (a) of between 5 and 30°.

2. A device according to claim 1, characterized in that the pivotal axis (Y-Y) is tangent to the roller (13) in the vicinity of the ascending side (21) of the strip.

3. A device according to claim 1, characterized in that the fixed structure (1) defines a plane (3) which is inclined at an angle (a) to the horizontal and comprises support and guide means (4) cooperating with complementary means (40) carried by the movable structure.

4. A device according to claim 3, characterized in that the support and guide means and complementary means carried by the movable structure comprise three subassemblies (31, 32, 33), each providing at least one pair of support surfaces (5, 41) and a pair of cylindrical guide surfaces (6, 42) centred on the pivot axis (Y-Y) between the two structures.

5. A device according to claim 4, characterized in that two of the subassemblies (31, 32) are disposed in the upper part of the inclined plane (3) and the third subassembly (33) is disposed in the lower part of this inclined plane.

6. A device according to any one of claims 3 to 5, characterized in that the lower part of the inclined plane (3) is disposed closer to the ascending side (21) of the strip (20).

7. A device according to any one of claims 1 to 6, characterized in that the roller (13) is carried by a structure (10a) which is mounted on an intermediate structure (10b) so as to be capable of pivoting relative to said intermediate structure about an axis (Z-Z) contained in a medial plane, at right angles to the axis (X-X) of the cylinder, said axis (Z-Z) extending at right angles to the si e of the strip and being situated at a distance below the axis (X-X) of the roller, the intermediate structure (10b) itself being mounted on the fixed structure (1) so as to be capable of pivoting about an axis (Y-Y) as defined in the preceding claims.

8. A device according to claim 7, characterized in that stoppage means (52, 53) are provided, on the one hand, between the movable structure (10a) and the intermediate structure (10b) and, on the other hand, between the intermediate structure (10b) and the fixed structure (1).

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