GB1558696A

GB1558696A - Arrangement for laterally displacing a travelling web

Info

Publication number: GB1558696A
Application number: GB3536177A
Authority: GB
Original assignee: Siemens AG
Current assignee: Siemens AG
Priority date: 1976-08-24
Filing date: 1977-08-23
Publication date: 1980-01-09
Also published as: DE2638022A1; FR2362782A1; SE7708886L; IT1084185B

Description

(54) AN ARRANGEMENT FOR LATERALLY DISPLACING A TRAVELLING WEB (71) We, SIEMENS AKTIENGESELL SCHAFT, a German company, of Berlin and Munich, West Germany, do hereby declare the invention, for which we pray that a patent may be granted to us and the method by which it is to be performed, to be particularly described in and by the following statement: The invention relates to an arrangement in web-conveying apparatus for lateral web displacement.

According to the present invention there is provided, in web-conveying apparatus, an arrangement for laterally displacing a web, the arrangement comprising: a first guide roller from which the web travels in an initial travel direction in a first web plane; a first deflecting roller which is spaced from the first guide roller, and over which the web is deflected through a right-angle into a second web plane; a second deflecting roller which is spaced from the first deflecting roller and over which the web is deflected through a right-angle into a third web plane which is parallel to the first web plane; and a second guide roller which is spaced from the second deflecting roller and which receives the web from the second deflecting roller travelling in a final travel direction, the rotary axes of the deflecting rollers being tiltable together in respective tilt planes, the initial travel direction being normal to the tilt plane of the first deflecting roller and the final travel direction being normal to the tilt plane of the second deflecting roller.

An arrangement for side register adjustment in accordance with the present invention enables a large lateral displacement of the web to be made which is dependent solely on the mutual spacing and degree of tilt of the deflecting rollers.

In the stationary case, no transverse forces occur in the web at the first approach, i.e. in the first web plane, which could lead, with differing longitudinal tensions across the width of the web, to displacement of the lateral web position.

The lateral register adjustment is completely uncoupled from the longitudinal register adjustment for which separate means may be provided. Mutual influences are excluded.

The present invention takes as its basis the fact that the web does not approach any roller of the arrangement obliquely when the vector of the web velocity, the axes of the web guide rollers and the clamping positions and tilt directions of the deflecting rollers are each perpendicular to one another and form the orthogonal axes of a spatial Cartesian coordinate system. The product of the angle of tilt and the web width is very much less than the distances of the deflecting rollers from the adjacent web guide rollers. The tilt movement of the deflecting rollers takes place, in each case, precisely in a tilt plane to which the web velocity vector is perpendicular. The mutual spacing of the two deflecting rollers determines the maximum deflecting ability of the arrangement and must accordingly be greater than zero. The tilt movement of the auxiliary rollers may not change the mean web length between the web guiding rollers.

By a normal vector of a plane is meant, in the sense of the linear analytic geometry of the space, a vector which is perpendicular to all the straight lines lying in the plane.

For a better understanding of the present invention, and to show how it may be carried into effect, reference will now be made, by way of example only, to the accompanying drawings, in which: Figure 1 shows a perspective view of web-conveying apparatus including an arrangement for laterally deflecting a conveyed web; Figure 2 is a side view of the apparatus of Figure 1; Figure 3 shows a section taken along the line III-III of Figure 2; and Figure 4Q and 4b are diagrams to explain the direction of tilt of the deflecting rollers.

The apparatus shown in Figure 1 may, for example, be part of a rotary printing machine. In Figure 1, a paper web 3 runs through a first clamping point comprising the nip between a first set of web guide rollers 1 la and 1 ib. The web velocity vector vl lies in a first web plane A of the web running out from the damp ing point between the web guide rollers 1 la, 1 ib. A first deflecting roller 1 deflects the web upwards through a rightangle 4 into a second web plane C. A second deflecting roller 2 deflects the web again through a right-angle 5 towards a second clamping point comprising the nip between a second set of rollers 12a and 12b. The web velocity vector v2 lies in a third web plane E of the web running into the second clamping point between the web guide rollers 12a, 12b. The two deflection angles 4 and 5 are each exact right-angles.

The first deflecting roller 1 is disposed at a distance a behind the first clamping point between the web guide rollers 1 la, 1 ib. The second deflecting roller 2 is disposed at a distance e in front of the second clamping point between the web guide rollers 12a, 12b. The two deflecting rollers 1 and 2 have a mutual spacing d.

The axis 1 ic of the web guide rollers 11 a is parallel to the axis of the web guide roller 1 lb. Both of these axes, and thus also the contact line of the first clamping point, are parallel to the contact line of the second clamping point and thus also parallel to the axis 12c of the web guide roller 12a and to the axis of the web guide roller 12b.

The deflecting roller 1 is tiltable in a first tilt plane B, outlined by a broken line, of which the web velocity vector vl of the web running out from the first clamping point constitutes a normal vector. The second deflecting roller 2 is tiltable in a second tilt plane D, also outlined by a broken line, of which the web velocity vector v2 of the web running into the second clamping point constitutes a normal vector. The tripod shown in Figure 4a thus applies to the first deflecting roller 1, and indicates that the direction of tilt kl of the first auxiliary roller 1 is perpendicular to the web velocity vector vl and to the axis 1 1c of the web guide roller 1 la or the contact line of the first clamping point. A corresponding tripod, shown in Figure 4b, applies to the second deflecting roller 2, where the direction of tilt of the second auxiliary roller 2 is perpendicular to the web velocity vector v2 and the axis 12c of the web guide roller 12a and thus of the contact line of the second clamping point.

The first tilt plane B, in which the first deflecting roller 1 is tiltable, is parallel to the second tilt plane D, in which the second deflecting roller 2 is tiltable.

The web plane A of the web running out from the first clamping point is parallel to the web plane E of the web running into the second clamping point. The web plane C between the two deflecting rollers 1 and 2 is perpendicular to the web planes A and E and has the web velocity vectors vl and v2 as normal vectors.

As may be seen from Figure 3, he two deflecting rollers 1 and 2 are each tilted in the same direction by the same angle of tilt x in the tilt planes B or D.

This ensures that the web 3 does not approach any of the rollers obliquely, i.e.

the axes of all of the rollers are perpendicular to the web travel direction.

WHAT WE CLAIM IS: 1. In web-conveying apparatus, an arrangement for laterally displacing a web, the arrangement comprising: a first guide roller from which the web travels in an initial travel direction in a first web plane; a first deflecting roller which is spaced from the first guide roller, and over which the web is deflected through a right-angle into a second web plane; a second deflecting roller which is spaced from the first deflecting roller and over which the web is deflected through a right-angle into a third web plane which is parallel to the first web plane; and a second guide roller which is spaced from the second deflecting roller and which receives the web from the second deflecting roller travelling in a final travel direction, the rotary axes of the deflecting rollers being tiltable together in respective tilt planes, the initial travel direction being normal to the tilt plane of the first deflecting roller and the final travel direc

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. web-conveying apparatus including an arrangement for laterally deflecting a conveyed web; Figure 2 is a side view of the apparatus of Figure 1; Figure 3 shows a section taken along the line III-III of Figure 2; and Figure 4Q and 4b are diagrams to explain the direction of tilt of the deflecting rollers. The apparatus shown in Figure 1 may, for example, be part of a rotary printing machine. In Figure 1, a paper web 3 runs through a first clamping point comprising the nip between a first set of web guide rollers 1 la and 1 ib. The web velocity vector vl lies in a first web plane A of the web running out from the damp ing point between the web guide rollers 1 la, 1 ib. A first deflecting roller 1 deflects the web upwards through a rightangle 4 into a second web plane C. A second deflecting roller 2 deflects the web again through a right-angle 5 towards a second clamping point comprising the nip between a second set of rollers 12a and 12b. The web velocity vector v2 lies in a third web plane E of the web running into the second clamping point between the web guide rollers 12a, 12b. The two deflection angles 4 and 5 are each exact right-angles. The first deflecting roller 1 is disposed at a distance a behind the first clamping point between the web guide rollers 1 la, 1 ib. The second deflecting roller 2 is disposed at a distance e in front of the second clamping point between the web guide rollers 12a, 12b. The two deflecting rollers 1 and 2 have a mutual spacing d. The axis 1 ic of the web guide rollers 11 a is parallel to the axis of the web guide roller 1 lb. Both of these axes, and thus also the contact line of the first clamping point, are parallel to the contact line of the second clamping point and thus also parallel to the axis 12c of the web guide roller 12a and to the axis of the web guide roller 12b. The deflecting roller 1 is tiltable in a first tilt plane B, outlined by a broken line, of which the web velocity vector vl of the web running out from the first clamping point constitutes a normal vector. The second deflecting roller 2 is tiltable in a second tilt plane D, also outlined by a broken line, of which the web velocity vector v2 of the web running into the second clamping point constitutes a normal vector. The tripod shown in Figure 4a thus applies to the first deflecting roller 1, and indicates that the direction of tilt kl of the first auxiliary roller 1 is perpendicular to the web velocity vector vl and to the axis 1 1c of the web guide roller 1 la or the contact line of the first clamping point. A corresponding tripod, shown in Figure 4b, applies to the second deflecting roller 2, where the direction of tilt of the second auxiliary roller 2 is perpendicular to the web velocity vector v2 and the axis 12c of the web guide roller 12a and thus of the contact line of the second clamping point. The first tilt plane B, in which the first deflecting roller 1 is tiltable, is parallel to the second tilt plane D, in which the second deflecting roller 2 is tiltable. The web plane A of the web running out from the first clamping point is parallel to the web plane E of the web running into the second clamping point. The web plane C between the two deflecting rollers 1 and 2 is perpendicular to the web planes A and E and has the web velocity vectors vl and v2 as normal vectors. As may be seen from Figure 3, he two deflecting rollers 1 and 2 are each tilted in the same direction by the same angle of tilt x in the tilt planes B or D. This ensures that the web 3 does not approach any of the rollers obliquely, i.e. the axes of all of the rollers are perpendicular to the web travel direction. WHAT WE CLAIM IS:

1. In web-conveying apparatus, an arrangement for laterally displacing a web, the arrangement comprising: a first guide roller from which the web travels in an initial travel direction in a first web plane; a first deflecting roller which is spaced from the first guide roller, and over which the web is deflected through a right-angle into a second web plane; a second deflecting roller which is spaced from the first deflecting roller and over which the web is deflected through a right-angle into a third web plane which is parallel to the first web plane; and a second guide roller which is spaced from the second deflecting roller and which receives the web from the second deflecting roller travelling in a final travel direction, the rotary axes of the deflecting rollers being tiltable together in respective tilt planes, the initial travel direction being normal to the tilt plane of the first deflecting roller and the final travel direc

tion being normal to the tilt plane of the second deflecting roller.

2. In web conveying apparatus, an arrangement as claimed in - claim 1, in which the two deflecting rollers are tiltable about a common tilt axis.

3. In web-conveying apparatus, an arrangement for laterally displacing a travelling web substantially as specifically described herein with reference to the accompanying drawings.