WO1999062702A1

WO1999062702A1 - Device for paper-lining and method for paper-lining

Info

Publication number: WO1999062702A1
Application number: PCT/SE1999/000917
Authority: WO
Inventors: Jan-Erik Carlsson
Original assignee: Lamina System Aktiebolag
Priority date: 1998-06-03
Filing date: 1999-05-28
Publication date: 1999-12-09
Also published as: SE9801974L; SE512441C2; DE19983258T1; AU4665599A; DE19983258B4; SE9801974D0

Abstract

The present invention relates to a device for the joining of two flat and essentially planar objects, comprising two guides (16, 18), one being arranged over the other, at least one longitudinal holder-on (60) on each guide, and drive assemblies (17, 21) on each guide, capable of driving said objects forward to a joining position and to the longitudinal holder-on. The invention is characterised by a stopping means (32) arranged at the joining position and capable of orienting the front edges of the objects in relation to each other, and a joining means, arranged ahead of the stopping means, as seen in the feeding direction, comprising pressing means (44, 50), rotatably arranged above and below the sheets at the joining position, hereafter denoted upper and lower pressing means, capable of pressing together the two fed-forward objects at their font edges, as seen in the feeding direction.

Description

DEVICE FOR PAPER-LINING AND METHOD FOR PAPER -LINING

TECHNICAL FIELD

The present invention relates to a device for the joining of two flat and essentially planar objects, comprising two guides, one being arranged over the other, at least one longitudinal holder-on on each guide, drive assemblies on each guide, capable of driving said objects forward to a joining position and to the longitudinal holder-on.

BACKGROUND OF THE INVENTION In a known machine for fully or semiautomatic lining of lower sheets of paperboard, cardboard or corrugated board, with upper sheets of paper, plastic film or paperboard, the upper side of the lower sheet is provided with an adhesive, before the two sheets are pressed together. Before being pressed together, the sheets must be brought in the right position - be registered - in relation to each other. This operation has, according to prior art, been performed by one side edge of the sheets having been pressed against a longitudinal holder-on, by aid of mechanical motional means, at the same time as the sheets are being fed forward to an end stop.

Other problems with known devices relate to the pressing together, after the sheets have been positioned. In these, the sheets are fed in between two rollers. If the two sheets are not positioned correctly in relation to each other, or if the upper sheet is relatively thin, the upper sheet is displaced or crumpled in relation to the lower sheet, with bad fitting and un-aesthetic longitudinal crumples as the result.

The above problems have been solved by a device according to the Swedish patent application 9600566-5, by the same applicant as the present invention, which patent application is hereby incorporated by reference.

In the device according to the above application, upper and lower sheets are fed forwards towards an end stop, whereby they are positioned in the sidewards direction during the feeding. When the sheets have reached the end stop, they are positioned at their front edge too and accordingly the upper and lower sheet are registered in relation to each other. After this, a presser foot is lowered and presses the sheets together at their front edges during a certain time period. The length of the time period depends largely on which type of adhesive that is used, i.e. hόw much time there is required for the adhesive to join the sheets at their front edges. Thereafter, the end stop is retracted and the sheets are fed through press rollers for final joining. The described device is functioning excellently for most types of sheet materials and adhesives. It has however been recognised that the press period becomes unacceptably long, due to the contact surface between the upper and lower sheets being so small, for certain types of materials, e.g. when single corrugated board is used as lower sheet, the upper sheet being glued to the ridges or battens of the lower sheet. In order to keep the press period as short as possible, i.e. to keep the capacity of the machine as large as possible, there is used adhesives with a relatively short time period for adhesion. Commercially, there is available a number of cheaper and more simple adhesives with longer time periods for adhesion, which at present can not be used due to capacity reasons.

ACCOUNT OF THE INVENTION

The object of the present invention is to solve the above problem complex in order to increase the capacity of the machine, at the same time as more simple types of adhesives can be used with a good result.

This is achieved according to one aspect of the invention, by a device according to the introduction which is characterised by a stopping means arranged at the joining position and capable of orienting the front edges of the objects in relation to each other, and a joining means arranged ahead of the stopping means, as seen in the feeding direction, comprising pressing means, rotatably arranged above and below the sheets at the joining position, hereafter denoted upper and lower pressing means, capable of pressing the two fed-forward objects together at their front edges, as seen in the feeding direction.

According to another aspect of the invention, it is characterised in that the pressing means are idle.

According to yet another aspect of the invention, the upper pressing means are resiliently mounted in the vertical direction.

Several advantages are obtained by a device according to the invention. By the pressing unit comprising rotating pressing means instead of a presser foot and a rail as holder-on, and by the wheels being idle, both the sheets may be fed forward for complete pressing together directly after the registering and pressing together in the front edges, without risking that the sheets slide in relation to each other. This results in that the time period for pressing together, which time period could be relatively long in the previous device, can be considerably decreased. Moreover, there may be used adhesive types which exhibit a longer time period for adhesion, without the end result being at stake.

Capacity improvements of up to 50% in relation to the previous embodiment have been achieved with the device according to the invention, in tests.

These and other aspects of and advantages with the present invention will be apparent from the detailed description of a preferred embodiment, and of the subsequent claims.

SHORT DESCRIPTION OF THE FIGURES

In the following description of a preferred embodiment, there will be referred to the enclosed drawings, of which

Fig. 1 a side view of a device for lining of sheets, comprising the invention according to the application,

Fig. 2 is showing a detailed view of a pressing unit, and

Fig. 3 is showing a detailed view of the pressing unit in Fig. 2, along the line HI-ILI in Fig. 2,

Fig. 4-10 is showing a registering and pressing cycle according to the invention.

DESCRIPTION OF A PREFERRED EMBODIMENT

Referring to Fig. 1, there is shown a device for lining of sheets, of a type which is described in more detail in Swedish patent application 9600566-5. Below, only the components which are necessary for the present invention will be described. For a more detailed description, reference is made to the above mentioned application.

The device for lining of sheets 10 comprises an upper 12 and a lower 14 hopper for sheets which are to be lined. An upper sheet guide 16 is arranged to the upper hopper, which sheet guide comprises feed-forward devices 17 and positioning devices 60 for forward feeding and positioning in the sidewards direction of upper sheets.

A lower sheet guide 18 is arranged to the lower hopper, which sheet guide comprises a adhesive works 20, feed-forward devices 21 and positioning devices (not shown) for adhesive coating and forward feeding and positioning of lower sheets.

Moreover, the device for lining of sheets comprises transmitters and control devices for surveillance and control of the sheets. Subsequent to the sheet guides, as seen in the feeding direction, the device is equipped with a pressing unit 30, which will be described in connection with Fig. 2. The pressing unit 30 comprises an end stop or holder-on 32, which runs across the feed-forward direction M. The end stop 32 is arranged on an arm 34, which arm is rotatably journalled in bearings about a shaft 36, so that the end stop, by aid of a suitable rotating means (not shown), may be rotated from an essentially vertical position, where it acts as a holder-on for the sheets, to a position where the end stop is out of the way for the continuing forward feeding of the sheets. Ahead of the end stop, as seen in the feeding direction M, a lower rail 38 is arranged across the feed-forward direction. Above and ahead of the lower rail 38, there is arranged a slide plate 40, which plate is intended to guide the upper and lower sheets towards the end stop 32. Recesses 42, with a certain distance them between, are arranged in the lower rail 38 and the slide plate 40, Fig. 3. Wheels or rollers 44 are rotatably arranged in the recesses. Corresponding recesses are arranged in the end stop 32.

An upper rail 46 is arranged above the lower rail. The upper rail 46 too runs across the feed-forward direction M and is arranged to be vertically displaceable. The upper rail too is equipped with recesses 48, in which recesses rollers or wheels are rotatably journalled in bearings. The wheels in the upper rail 46 are arranged with a certain resilient freedom of movement in the vertical direction. The recesses and wheels in the upper rail are arranged to be placed vertically above the wheels in the lower rail.

Downstream the end stop 32 there is arranged a unit with two press rolls 52 above each other, the upper roll being vertically displaceable in order to control the press force them between. The rolls are preferably designed in a relatively elastic material.

In the following, the operation of the device according to the invention will be described in connection with the figures 4-10. Fig. 4 is showing the pressing unit being ready to receive sheets. The end stop 32 is raised and the upper guide is raised to its upper position. In this position, an upper sheet is fed forward from the upper sheet guide. During the feeding forward, the sheet is being positioned in the sidewards direction by one of its side edges sliding against a holder-on 60, Fig. 2. The upper sheet is fed forward to the end stop, Fig. 5, where it is positioned in the feed-forward direction by its front edge abutting the end stop. Shortly thereafter, the adhesive coated lower sheet is fed forward to the end stop, Fig. 6. During the feeding forward, the lower sheet too has been positioned in the sidewards direction by one of its side edges abutting a holder-on (not shown), and in the feed-forward direction by its front edge abutting the end stop. Consequently, the sheets are now registered in relation to each other. Hereafter, the upper rail 46 is led down towards the lower rail 38, whereby the wheels 50 in the upper rail are pressed against the sheets, and whereby the wheels 44 in the lower rail act as holder-on's, Fig. 7, the major part of the press force obtained by the resilient mounting of the upper wheels. The resilience also leads to that the press result not being affected by certain irregularities in the sheets. The pressing of the wheels results in the upper and lower sheets adhering to each other in these points. Immediately thereafter, the end stop is lowered and the two sheets are being fed past the wheels and in between the rolls, Fig. 8-9, where they are joined together completely. Thereafter, the end stop is raised again and the upper rail is brought to its upper position, waiting for new sheets.

The press position of the upper rail, i.e. its lower position, depends on the thickness of the sheet materials. By the upper wheels being arranged resiliently, a good pressing together is obtained even if the sheets exhibit certain irregularities or non-planities. Reference is made to the Swedish patent application 9600566-5, for a more detailed description of the feeding forward of the sheets and the surveillance thereof.

It is to be understood that the invention is not limited to the above described and on the drawings shown embodiment, but may be modified within the scope of the following claims. Accordingly, it may be conceived to use balls which are rotatably arranged in the upper rail, instead of wheels or rollers.

Claims

1. Device for the joining of two flat and essentially planar objects, comprising

- two guides (16, 18), one being arranged over the other, - at least one longitudinal holder-on (60) on each guide, and

- drive assemblies (17, 21) on each guide, capable of driving said objects forward to a joining position and to the longitudinal holder-on, characterised by

- a stopping means (32) arranged at the joining position and capable of orienting the front edges of the objects in relation to each other, and

- a joining means, arranged ahead of the stopping means, as seen in the feeding direction, comprising pressing means (44, 50), rotatably arranged above and below the sheets at the joining position, hereafter denoted upper and lower pressing means, capable of pressing the two fed-forward objects together at their front edges, as seen in the feeding direction.

2. Device according to claim 1, characterised in that the pressing means (44, 50) are idle.

3. Device according to claim 1 or 2, characterised in that the pressing means comprise rollers, wheels, balls or other rotatable means.

4. Device according to claim 1 or 2, characterised in that the upper pressing means (50) are arranged to be movable essentially vertically to and from the lower pressing means and that the upper and lower pressing means are arranged vertically above each other.

5. Device according to any of claims 1-4, characterised in that the upper pressing means are arranged to be resilient in the vertical direction.

6. Device according to any of the preceding claims, characterised by a pair of rollers (52), arranged downstream the joining position, capable of pressing the two objects completely together.

7. Method for the joining of two flat and essentially planar objects, the two objects being fed forward along an upper and a lower guide, respectively, to a joining position, characterised in the steps of - orienting the sheets in the sidewards direction during the feed-forward,

- feeding the sheets forward to a holder-on, whereby they are oriented in the feeding direction and whereby they are oriented in relation to each other,

- pressing the sheets together in their front edges, by aid of pressing means which are rotatably journalled in bearings above and below the sheets,

- rectracting the holder-on from the joining position and feeding the sheets onwards while the pressing means abuts the sheets.

8. Method according to claim 7, c h a r a c t e r i s e d i n that the objects are joined together completely after the pressing together.