GB2097765A

GB2097765A - Separately winding of longitudinally divided webs

Info

Publication number: GB2097765A
Application number: GB8121468A
Authority: GB
Original assignee: Jagenberg Werke AG
Current assignee: Jagenberg Werke AG
Priority date: 1981-04-30
Filing date: 1982-04-29
Publication date: 1982-11-10
Also published as: IT8220424A0; ES8304875A1; BR8201614A; JPS58100050A; IT1150934B; FI821210L; FI821210A0; ES511864A0; FR2508017A2

Abstract

Longitudinally divided webs are wound on at least two rolls (6) supported either side of a vertical plane passing through the axis of a driven support roller (7) on the upper half of the periphery of the support roller (7). The ratio of the diameters of the support roller (7) and of the winding rolls (6) in the fully wound state is 1 to 2.5. The angle ( alpha ) between the vertical plane containing the axis of the support roller (7) and the supporting line of the winding rolls (6) is not greater than 40 DEG . A weight-relieving device (8) which can be adjusted as regards its force depending on the respective diameter of the winding rolls (6) acts on the axis of the winding rolls. Pressure rollers (16) mounted on vertically movable crossbars (13) can bear on the rolls (6) at the commencement of a winding operation. <IMAGE>

Description

SPECIFICATION Apparatus for the separate winding of longitudinally divided webs The invention relates to an apparatus for the separate winding of londitudinally divided webs on at least two winding rolls placed on the upper half of the periphery of a single driven support roller alternately on one and the other side of a vertical plane passing through the axis of the support roller.

Apparatus of this type are already known, for example from German Patent 20 48 715.

Apparatus operating according to two different principles are known for winding longitudinally divided webs on two winding rolls. In the winding apparatus operating according to one principle and known for example from German Patent 11 96 463, the winding rolls are located in an axis parallel manner on two driven support rollers arranged at a slight distance apart in an axis parallel manner.

Since the winding rolls are supported with their entire weight on the support rollers, as further material is wound on the winding rolls and their weight increases, the contact pressure between the latter and the support roller increases. Consequently, increasing mechanical stress is applied to the respectively outermost layers of web, the winding hardness increases as a result of the increasing roll gap effect and finally this may even lead to tearing of the material web, when the stress becomes excessive. Furthermore, the roll gap effect on two support rollers also increases the tension on the material web.

In the second apparatus known from German Patent 20 60 758 for example, two winding rolls are arranged diametrically on a common support spindle in an axis parallel manner and with the axes located in the same horizontal plane, in which case the winding rolls are mounted axially separately from each other and the mounting is able to move horizontally radially with respect to the support roller as the winding increases. in this apparatus, the actual weight of the winding roll is taken-up by the axial mounting. The loads which increase as winding continues, due to the actual weight of the winding roll, act on the centre of the winding roll and in this case lead to tearing of the web.Furthermore, the centre must also absorb the horizontal forces necessary for the linear pressure, which forces must be introduced by means of pressure cylinders from outside at the ends of the winding rolls. The weight forces acting vertically and the pressing forces acting horizontally are added together geometrically.

Now it is the object of the present invention to provide a winding apparatus which facilitates the winding of wider, longitudinally divided webs to form large rolls having a uniform winding hardness, in an optimum manner. Large heavy rolls should thus be able to be wound on spindle-free winding machines which do not have excessive dimensions.

The object is achieved according to the invention by an apparatus of the afore-mentioned type with the features characterised in claim 1.

In the apparatus according to the invention, an advantageous division of the forces produced by the actual weight of the winding rolls occurs. Only part of the weight of the winding rolls acts on the support roller, the other part is taken up by the weight-relieving device. The introduction of external forces for the production of linear pressure can be dispensed with.

With the given ratio of the diameters of the support roller and of the winding rolls as well as of the position of the line of contact between the support roller and the winding roll, not only are favourable load-distribution ratios obtained, but also an advantageous winding of the winding roll with a winding hardness which is not too high, but also not too low. With a ratio of diameters above 2.5, the support roller becomes uneconomically large. One strives for a uniform winding hardness irrespective of the diameter of the winding roll, in order to avoid excess stress on the material both inside the roll as well as in the outer layers. By regulating the weight-relieving device, then the support roller can be relieved of the weight of the rolls in a manner adapted to the weight of the winding roll corresponding to the respective degree of winding.By co-ordinating the magnitude of the weight-relieving action with the respective diameter of the winding roll, i.e. a weightrelieving effect varying over a period of time, the contact pressure of the winding roll against the support roller is controlled in the sense of influencing the winding hardness in the desired manner.

Without these measures, the contact pressure of the winding roll against the support roller and thus the winding hardness would increase. The weight-relieving device may consist of hydraulic or pneumatic cylinderpiston units or electrical driving units.

By combining this weight-relieving device with winding carriages able to be adjusted on a cross-bar horizontally to different web widths, a simple and compact construction is facilitated.

According to a preferred embodiment of the apparatus according to the invention, a pair of pressure rollers mounted on a rocking lever can be pressed against the periphery of the winding sleeve. Due to this, particularly at the beginning of winding, the winding roll is pressed with an adjustable force against the support roller and is held in its position. In the course of winding of the winding roll, the rocking lever with the pair of pressure rollers is raised from the periphery of the winding roll.

In a further preferred embodiment, the rocking lever is pivoted on a cross-bar which can be raised and lowered, which may also serve as a protective device. When the rocking levers with the pressure rollers and the crossbar are no longer required, the cross-bar can be raised, after which the winding rolls can be removed from the machine in an unimpeded manner after the completion of the winding operation.

The invention is described in detail with reference to the embodiment illustrated in the drawings: Figure 1 is a side view and Figure 2 is a plan view of an embodiment of the apparatus according to the invention with hydraulic or pneumatic axial relieving of the winding roll.

The web 2 is withdrawn from a delivery roll 1 and divided longitudinally by circular cutters 3 into several strips 4, which are wound separately (Fig. 2).

The winding apparatus provided for this consists of a support roller 5, which is driven.

Located on the support roller 5 are winding rolls 6, whereof the weight of each is relieved separately. The winding rolls 6 lie alternately on one and the other side of the vertical plane 7 passing through the axis of the support roller 5, on the upper peripheral surface of the support roller 5 (Fig. 2), respectively at an angle a c 40".

A separate weight-relieving device is provided for each winding roll 6. Each device consists of a pneumatic or hydraulic cylinderpiston unit 8, whereof the piston rods 9 bring about axial relieving of the winding rolls 6 by way of journals 10 inserted at both sides in the open ends of the winding rolls 6. This relieving action can be controlled or regulated infinitely during the increasing winding on the winding rolls 6, in order to compensate for the increasing weight of the winding rolls 6 by the weight-relieving device 8,9 so that a desired linear pressure is achieved, which determines the winding hardness.

Each weight-relieving device 8,9 is attached to a winding carriage 12, which is arranged to move longitudinally on the cross-bar 11. The winding carriage 1 2 and weight-relieving device 8,9 together form the winding stand, which can be adjusted to various widths of the strips 4 and the various locations of the cutting points at right angles to the direction of travel of the web.

Rocking levers 14 are pivoted on cross-bars 1 3 which can be raised and lowered, which levers are pressed against the winding rolls 6 by means of a pivot drive 1 5 with the pair of pressure rollers 16, at the beginning of the winding operation, as shown in dot dash lines in Fig. 1. In the right-hand part of Fig. 1, the cross-bar 1 3 is also shown in a central position (broken line), in which it can serve as a protective device with respect to the winding region of the machine. Before removing the winding rolls 6 after completing winding, the cross-bars 1 3 with the rocking lever 14 and pressure rollers 1 6 are moved into the upper end position shown in full line in Fig. 1.

Claims

1. Apparatus for the separate winding of longitudinally divided webs on at least two winding rolls placed on the upper half of the periphery of a single driven support roller alternately on one and the other side of a vertical plane passing through the axis of the support roller, wherein the ratio of the diameters of the support roller and of the winding rolls in the fully wound state is 1 to 2.5, the angle (a) between the crest line of the support roller and the supporting line of the winding rolls is not greater than 40 and a weight-relieving device which can be adjusted as regards its force depending on the respective diameter of the winding rolls acts along the axes of the winding rolls.

2. Apparatus according to claim 1, wherein provided on the cross-bar are winding carriages which are able to move longitudinally individually, which can be adjusted respectively in pairs to the width of web strips to be wound and are thus aligned with the cutting points and to which the weight-relieving device is attached.

3. Apparatus according to claim 1 or 2, wherein a pair of pressure rollers mounted on a rocking lever is able to be pressed against the periphery of the winding roll.

4. Apparatus according to claim 3, wherein the rocking levers are pivoted on a crossbar which can be raised and lowered.

5. Apparatus for the separate winding of longitudinally divided webs, substantially as herein described with reference to the accompanying drawings.