Device for cutting a protective layer away from a material roll

Device for cutting a protective layer away from a material roll of web-formed material, comprising a rotation device which rotates the roll. The rotation device includes at least two rotatable carrier rollers, on which the material roll is supported and is rotated. In this way the protective layer on the material roll is cut away from the roll during a cutting operation by a cutting tool device. This contacts the roll during its rotation. The rotatable carrier rollers form lifting and carrying devices on a mobile load carrier in order to support the material roll whilst rotating it during the cutting operation and in order to transport the material roll to and, respectively, from a chosen place for the cutting operation.

TECHNICAL FIELD 
The present invention relates to a device for cutting a protective layer 
away from a material roll of web-formed material, comprising a rotation 
device intended to rotate the roll, whereby the rotation device includes 
at least two rotatable carrier rollers, on which the material roll is 
supported and is arranged to rotate, whereby the protective layer on the 
material roll is cut away from the roll during a cutting operation by 
means of a cutting tool which is arranged to contact the roll during its 
rotation. 
For transport and storage of material rolls comprising web-formed material, 
for example paper, these are provided, in connection with manufacture, 
with a packaging in form of one or more protective layers on the end faces 
of the roll or covering layers of a strong material, for example coarse 
paper. Before the roll of web-formed material contained in the packaging 
is used, e.g. in the graphics industry, packaging industry etc., the 
protective layer is removed before the web material can be unrolled. 
STATE OF THE ART 
It is known in the art to remove the protective layer from material rolls 
by the material roll being transported to a station for so-called 
roll-stripping, whereby the roll is normally transported by means of a 
truck, unloaded to a rotation device at the station and whereupon by means 
of a knife the packaging is cut open during rotation of the roll. After 
removal of the packaging the material roll is again loaded onto a suitable 
load carrier for further transport to a following station for unrolling of 
the web-formed material. The actual removal of the protective layer is a 
relatively fast procedure, whilst the total procedure is however 
lengthened unfavourably by an unloading procedure both before and after 
the removal of the protective layer. 
The object of the present invention is to facilitate the procedure with 
removal of the protective layer from material rolls. 
SUMMARY OF THE INVENTION 
Said object is achieved by means of a device according to the present 
invention, which is characterized in that said rotatable carrier rollers 
form lifting and carrying means on a mobile load carrier in order to 
support the material roll whilst rotating it during the cutting operation 
and to transport the material roll to and, respectively, from a chosen 
place for the cutting operation.

DESCRIPTION OF PREFERRED EMBODIMENT 
The device according to the invention, in a developed embodiment, can 
consist of a stationary unit 1 and a mobile unit 2. The stationary unit is 
formed from a stationary cutting device which is fixedly attached onto a 
floor 3 and supports a cutting tool in the form of a knife unit 4, which 
projects sidewardly from a stand with a control and drive unit 5 for the 
cutting device 1. The knife unit 4 is for instance movably arranged 
relative to the control and drive unit 5 for giving controlled movement 
between a retracted position, for example retracted to a hidden position 
inside the unit 5, and a projecting cutting position shown in FIG. 2 and 
possibly also movable sideways, i.e. essentially horizontally. The cutting 
edge 6 of the knife unit extends preferably in a vertical plane or at a 
small angle to this. 
The mobile unit 2 is built like a mobile load carrier, for example like a 
so-called auto carrier i.e. a self-driven self-controlled load vehicle 
which moves between determined positions. The vehicle can either follow a 
predetermined path, choose between several different predetermined paths 
or be programmed to choose by itself suitable routes between stations. The 
freedom of movement of the mobile unit is dependent on the chosen 
technique for controlling the unit. A commonly occurring control technique 
is based on fixedly inlaid control loops in the floor, whilst a more 
flexible solution is constituted by a previously known navigation system 
which is based on a rotating laser carried by the vehicle, which detects 
the reflections from fixed reflection points in the premises. By measuring 
the laser beam's angle relative to a reference line in the horizontal 
plane during reflection from at least two reflection points, the position 
can be determined and the vehicle controlled according to a chosen path by 
means of control equipment. 
The mobile unit 2 is made up of a wagon 7 with at least three wheels 8, 9 
and 10, of which at least one constitutes a steering wheel which is 
controlled by means of the automatic control equipment. The steering wheel 
10 or any of the other wheels 8, 9 serve(s) as a drive wheel which is 
driven by a drive motor for displacement of the wagon 7 with the desired 
speed and for starting and stopping in chosen positions. The wagon 
presents a lifting device 11 in the form of a so-called forklift in which 
the lifting device is designed as a raisable and lowerable unit, movable 
along a guide 12. The lifting device 11 presents two lifting and carrying 
members 13, 14, which are formed by two carrying rollers. These form a 
rotation device and are therefore rotatably carried in the part of the 
lifting device which is formed by a vertical crab 15 which by means of a 
non-depicted drive mechanism is movable vertically along the guide 12. The 
carrying rollers 13, 14 thereby form, in the shown example, fork legs 
positioned essentially parallel to each other and at a suitable respective 
distance such that they can support and rotate a roll 16 of continuous 
material web, e.g. paper. The roll is essentially cylindrical with a 
cylindrical outer surface 17 and two end faces 18. The roll normally 
presents a central core 19 in the form of a tube on which the material web 
is rolled up. The roll 16 is completely or partially enclosed in a 
protective layer which surrounds at least the end faces 18 and is normally 
made from a layer of strong paper. The protective layer can even cover the 
outer surface 17 completely or partially. The most common form of the 
protective layer is a sheet of paper attached on each one of the end 
faces, said sheet of paper being folded with a part over the roll's 
circular edge 22, 23 and glued against the cylinder outer surface 17. It 
is normally sufficient that the sheet extends a few centimeters over onto 
the cylindrical surface. 
The carrying rollers 13, 14 present a suitable, relatively small diameter 
and necessary length in order to be able to be inserted on either side of 
the support surface of the material roll on a base. It is realised that 
the roll is collected from a level above the base 3, for example on a 
cradle or similar. The crab 15 can also be arranged such that both carrier 
rollers 13, 14 are movable sideways with respect to each other, preferably 
by means of a highly geared drive motor, whereby the carrying rollers can 
be adapted to different dimensions of material rolls which are to be 
lifted. The crab 15 further presents a drive motor for rotation of one or 
both of the carrying rollers 13, 14 so that after activation they can be 
made to rotate around their longitudinal axle 20 for rotation of the 
material roll 17 around its geometrical longitudinal axis 21. This 
rotation can be activated either manually by means of a manoeuvring member 
on the mobile unit 2 or remotely controlled via control and drive unit 5 
or a non-depicted central computer in the material handling system. 
The idea with the arrangement according to the invention is thus to remove 
the protective layer, i.e. the packaging, from the material roll in an 
efficient manner. In this example it is required that the protective layer 
should be removed from the end surfaces 18, which occurs in the following 
manner: The material roll 16 is carried into position by means of the 
mobile unit 2 from a warehouse, production site or similar, to the cutting 
position shown in FIG. 2, whereupon the rotation device is activated. This 
activation can occur shortly before or when the mobile unit 2 is located 
at the position shown in FIG. 2 close to the cutting device 1, whereby 
also the knife unit is activated to contact the periphery 17 of the 
material roll 16 and to penetrate the outer surface at one edge portion 
22, 23 at a time. The packaging of the material roll 16 is made of a 
strong material, for example coarse paper in one or more layers, which 
thus shall be removed from the roll on the end faces 18 before the 
material web can be unrolled from this. Cutting open of the packaging by 
means of the cutting device 1 is achieved when the material roll 16 
rotates whilst the knife unit 6 is made to penetrate through the 
packaging. This occurs with the mobile unit 2 and the knife unit 6 
standing still in the position shown in FIG. 2. The knife unit is started 
and is held as near as possible to the edge portions 22, 23 of the 
material roll, whereby a purely annular complete cutline is achieved which 
thus cuts off the packaging over the end part of the roll. After a 
movement of either the knife unit or the mobile unit in the longitudinal 
direction of the roll, the knife unit is placed against the other end 
part, whereafter the roll is rotated and the packaging at the other end 
face is cut off in a similar manner whereby the protection layer falls 
down or is removed by hand. 
After finishing cutting of the packaging, the mobile unit 2 can be 
activated in order to move to the next station and thus take with it the 
material roll without any load transfer procedure. 
The invention is not limited to the embodiments described above and shown 
in the drawings, but can be varied within the scope of the appended 
claims. For example it is imaginable that the actual driven rotation of 
the roll occurs by way of drive means which is connected to a drive motor 
in the stationary unit 1. The drive means can consist of a drive roll 
which lies against the periphery of the roll or eccentrically against one 
end surface. A drive axle with engagement means can alternatively be 
coupled to the centre of the roll. In a simpler embodiment, the stationary 
unit 1 can be replaced by a person holding a cutting tool such as a knife 
in a manner which corresponds to that described above, i.e. during 
rotation of the roll on the mobile unit. In this way any suitable position 
whatsoever can be chosen for the cutting operation. For cutting of a roll 
completely or only of the packaging surrounding the outer surface, the 
knife unit can be made to perform a sideways movement along the roll 
during its rotation whereby a spiral-formed cutline is obtained and the 
protective layer can be removed. 
In practice the carrier members 13, 14 are made from several shorter 
rollers which are rotatably carried on the lifting forks of the mobile 
unit.