EP3747608A1

EP3747608A1 - Apparatus and method for fixing a material

Info

Publication number: EP3747608A1
Application number: EP20178334.7A
Authority: EP
Inventors: Bjarne Linding; Bjarne HARBO; Tue Bjørn Fyhn
Original assignee: VKR Holding AS
Current assignee: VKR Holding AS
Priority date: 2019-06-06
Filing date: 2020-06-04
Publication date: 2020-12-09
Anticipated expiration: 2040-06-04
Also published as: PL3747608T3; EP3747608B1

Abstract

The apparatus (1) for fixing a predefined length of a material comprises a substrate (2), a fixing band (8) and retraction means (7). The fixing band (8) can be moved between two states, a fixing state wherein the fixing band is fixed to the substrate (2) by a magnetic force between the substrate and the fixing band, the fixing state being for fixing a predefined length of a material between the fixing band and the substrate, and a rolled-up state wherein the fixing band is rolled from the fixing state by having the retraction means applying a retraction force.

Description

Technical Field

The present invention relates to an apparatus for fixing a predefined length of a material, the apparatus comprising a substrate, a fixing band and retraction means. The invention furthermore relates to a method for fixing a predefined length of a material with said apparatus.

Background Art

The fixing, or fixation, of material, e.g. large cloths, screening bodies, sheets, fabrics, planar metals, prior to treatment of the material is often cumbersome, requires a large amount of factory space, poses a work hazard for factory workers and presents a risk of damaging or unwanted marking of the fixated material during the fixing, handling or treatment of the material. When the treatment of the fixed material comprises a step of cutting, painting, printing or stamping, it is of particular importance that the material is fixed in a very precise, even and firm manner, e.g. to obtain a clean and defined cut or marking of the fixed material. An example for fixing of a material for the treatment of said material is the manufacturing of screening devices, such as roller blinds. Such screening devices typically have a flexible screening body and the manufacturing thereof traditionally includes a large number of steps requiring manual handling. In addition to contributing to the production costs, the work involved often requires precision in measuring and cutting the screening body to the correct size. In a manual operation the material can be fixed to a cutting table with a rod prior to cutting the material along the rod. Typically, the screening body is fixed by pressure from transverse bands or rods as described in GB2388397A1 . Such systems may present a serious work hazard for factory workers whose fingers or arms can be caught in the apparatus during the fixing process. Furthermore, subsequent treatment of the material involves unguided use of a sharp tool. Also, this work is in addition often monotonous, cumbersome, tiring and the transverse bands or rods can damage the often valuable materials during the process of fixing.
Over the years, several attempts have been made to facilitate an alternative approach for the fixing process of materials, and to some extent, automated solutions have been successfully devised. Such alternative approaches are presented in US4086731A and US4362077A .
However, there is still room for improvement, particularly with respect to security, precision and simplicity, regarding fixing of material prior to material treatment and.

Summary of Invention

With this background, it is therefore an object of the invention to provide an apparatus by which the fixing of a material, preferably a planar material, is facilitated and a method for fixing a predefined length of a material using said apparatus.
In a first aspect of the invention, this and further objects are achieved with an apparatus for fixing a predefined length of a material, the apparatus comprising a substrate, preferably a planar substrate, a fixing band and retraction means, wherein the fixing band comprises a, a first end and a second end, the first end being located at a longitudinal end of the fixing band and the second end being located at the opposite longitudinal end of the fixing band, the fixing band being movable between two states, a fixing state in which the fixing band is fixed to the substrate, the fixing state being intended for fixing the predefined length of a material between the fixing band and the substrate, and a rolled-up state in which the fixing band is rolled up from the fixing state, characterised in that the fixing band comprises a magnetic material, that the substrate comprises a magnetic material, and that the retraction means are configured to deliver a retraction force to the fixing band in a longitudinal direction of the fixing band, wherein the fixing band in the fixing state is fixed to the substrate by a magnetic force between the magnetic material of the fixing band and the magnetic material of the substrate, and wherein in the rolled-up state the fixing band is rolled up from the fixing state by allowing the retraction means to apply a retraction force at the second end of the fixing band towards the first end of the fixing band.
It has been found that fixing of a material can be carried out in a simple and easy manner with the apparatus provided by the invention, where the operator has a clear overview of the working area and the material positioned thereon when the fixing band is in the rolled-up state. The presented apparatus allows for simple and safe fixing. The use of fixing via magnetic force further gives advantages regarding precision and safety, as the magnetic force between the substrate and the fixing band can easily be controlled to be within a range where no serious harm can be done to an operator of the apparatus. Further the magnetic force can be used to guide the position that the fixing band fixes the length of material to the substrate allowing for extra precision. Having a rolled-up state also gives the advantages of having a compact solution, which when not fixed to the substrate is easy to handle.
By the term "fixing" within the context of the present invention is meant temporary, releasable retention of the length of material relative to the substrate.
By the term "magnetic material" within the context of the present invention is meant any ferromagnetic or ferrimagnetic material.
In a presently preferred embodiment the magnetic material comprised in the fixing band and/or the magnetic material comprised in the substrate are permanent magnets. The use of permanent magnets is cheap, simple and does not require electrical operation. It is also possible to use permanent magnets with different magnetic characteristics and strengths, e.g. permanent magnets arranged such that their magnetic strength is gradually decreasing or increasing. Only one of the components fixing band and substrate needs to be provided as an active magnet, while the other can be of a suitable magnetic material, or both components are formed as magnets. This provides for a versatile and flexible solution in the configuration of the apparatus. Alternatively, at least one of the fixing band and the substrate may be an electromagnet. Electromagnets are a versatile solution wherein easy control over the forces between the substrate and fixing band is given. The material fixing via magnetic forces is precise and reduces the work hazard for an operator. If an operator accidentally enters the space between the fixing band and the substrate with a finger or an arm, the fixing band will cause little to no damage to the operator, as either the fixing band will come to a stop, or it will roll over the object in its path with a harmless amount of force. Furthermore, it has been found that the relatively weak magnetic force which is needed for material fixing minimizes damage to the material during its fixing. Another advantage of the magnetic fixing of the material is that the material is fixed in a substantially even and uniform manner which allows precise treatment of the fixed material, such as cutting of the fixed material.
In another embodiment, the fixing band is formed by a plurality of units, the units being arranged transversally in the longitudinal direction of the fixing band, the units within the plurality of units being bendingly connected to each other. Forming the units with a bending connection allows for good mutual movement characteristics of the fixing band when rolling up and rolling out the fixing band. When increasing the number of units per fixing band length, the diameter of the rolled fixing band may decrease advantageously. While the fixing band is in its rolled-up state, the operator has a clear overview of the working area and the material positioned thereon.
In yet another embodiment, all the units comprise a permanent magnet, and the substrate comprises an equal number of permanent magnets, the permanent magnets comprised in the substrate being arranged in a corresponding shape as the permanent magnets comprised in the fixing band when the fixing band is in the fixing state, so that when the fixing band is in the fixing state the permanent magnets comprised in the fixing band and the permanent magnets comprised in the substrate attract each other.
The magnets used in the apparatus may be selected to have similar, the same or different characteristics, e.g. magnetic strength. Also the size and shape of the magnets can be selected independently from another, where the shape of the magnets for example can be longitudinal, rectangular, or circular.
In another presently preferred embodiment, the cross-section of each unit is formed substantially as a wedge having its longer dimension at the bottom. Being wider at the bottom of each unit than at the top of each unit, allows the units to contribute to a smooth transition from the fixing state to the rolled-up state of the fixing band and vice versa. It furthermore has been proven that such a shape results in the fixing band in its rolled-up state being more compact and therefore reduces the amount of total apparatus space.
In a development of the presently preferred embodiment, the units of the fixing band are pivotally connected via integrated hinges to each other at the bottom of the units. The integrated hinges between the units provide a simple but flexible connection and further contribute to a smooth transition of the fixing band from a rolled-up state into a fixing state and vice versa. With integrated hinges it is meant that the hinges and units are formed from the same material. Alternatively, to the usage of integrated hinges it would also be possible to connect the units hingedly by screws, welding, gluing, soldering or having connectable or disconnectable hinges connected to the units. The benefit of the latter is that the length of a band can be easily set or even changed.
In yet another embodiment the retraction means comprises a string attachable to the fixing band, preferably at the second end of the fixing band, the retraction means are arranged to pull said string. This arrangement enables retraction of the string and leads to the transition of the fixing band from the fixing state into the rolled-up state. In this case, the retraction is carried out by means of pulling. Alternatively, the retraction may be carried out by pushing, or by a combination of a pushing/pulling mechanism. It is further possible to pull the string via a pulley system or an automated system, where the system can be initiated by a button or other control means. In a further development of this embodiment, the units of the plurality of units comprises a longitudinally through-going hole, the string going through at least some of the through-going holes. To simplify the apparatus, only some of the units could be provided with a through-going hole and the remaining units with a U-shaped recess allowing passage of the string, and the string could run through the holes in only some of the units, for instance every second unit, or it might even be considered to let the string go through only the last unit. It is noted that the term "string" is not limited to a particular cross-sectional geometry and may be substantially cylindrical or flat and comprising one or more parts. The string or strings could also run outside the band.
The string attached to the second end of the fixing band can be arranged to go through the through-going holes. It has been found that a string going through said holes of the units supports the transition of the fixing band from the rolled-up state into the fixing state and vice versa. Also a string going through said holes will reduce the likelihood of accidental interference between an operator and said string. Alternatively, the string may go through a hole located on the very upper portion of the unit. Such a positioning of the hole can result in improved rolling of the fixing band, dependent on the design of the units and fixing band.
In yet another embodiment, the apparatus further comprising a flexible plate element, the flexible plate element being connected to the fixing band, so when the fixing band is in the fixing state the flexible plate element is located between the fixing band and the substrate. Two or more flexible plate elements per fixing band may be provided. Each flexible plate element may be made of any suitable material, such as polymers or metals. The flexible plate element contributes to a high precision during the fixing of the material. Another advantage thereof is that the fixed material can be treated manually by an operator by e.g. cutting or marking the fixed material in a precise manner along the flexible plate element. Further the flexible plate element may also perform a uniform pressure surface, to allow for the fixing band to pressure uniformly onto the material fixed between the substrate and the fixing band. The dimensions of the fixing band and/or the flexible plate element are chosen to allow proper operation. In a preferred further development of this embodiment, the flexible plate element is made of spring steel. In this manner, the operation is enhanced even further, since the flexible plate element may contribute to the rolling out or rolling up according to the configuration of the spring.
In yet another preferred embodiment, the apparatus further comprises a tool, wherein the fixing band has a track formed in the longitudinal direction of the fixing band, the tool being configured to be in engagement with the track and adapted to travel along the track and performing work on a material fixed between the fixing band and the substrate.
The apparatus can be equipped with many different types of tools which can be interchanged with another, e.g. a knife, a puncher, a marker, a laser, a spray. Depending on the length of the track, the tool can perform work over a portion of the width of the fixed material or perform work over the whole width of the fixed material.
In yet another embodiment, wherein the apparatus comprises at least one pair of fixing bands, the fixing bands within the pair being parallel to each other. This arrangement supports precise treating of the fixed material, especially during cutting of the fixed material. Also, the presence of a pair of fixing bands has proven to fix both parts of the fixed material after cutting said material in a safe and precise manner. This was found to reduce damages on the fixed material during fixation and treatment and leads to a lower rejection rate during the manufacturing process.
In a yet further presently preferred embodiment, the apparatus is adapted for use in manufacturing a screening device comprising a roller bar and a screening body, wherein the predefined length of the material is a screening body cloth material, wherein the apparatus furthermore comprises means for holding the roller bar, and means for supporting a roll of screening body cloth material..
In a second aspect of the invention, the invention relates to a method for fixing a predefined length of a material the method comprising the steps of;
in a first step providing an apparatus according to the first aspect of the invention, wherein the fixing band is in the rolled-up state,
in a second step placing a material on the substrate of the provided apparatus, and
in a third step fixing said material by bringing the fixing band from the rolled-up state to the fixing state by releasing the retraction force delivered by the retraction means. By doing this it has been found that the working area is clear for the operator e.g. to safely use tools for the treatment of the fixed material.
In a preferred embodiment, the method comprises the further steps of:

in a fourth step performing work on the fixed material, and
in a fifth step releasing said material, by letting the retraction means applying a retraction force large enough to overcome the magnetic force between the magnetic material of the fixing band and the magnetic material of the substrate, so as to bring the fixing band to the rolled-up state.

The work can be performed manually or with a tool engaged on the track of the fixing band. The work can be cutting, punching, spraying, marking, stamping, penetrating or any other suitable treatment of material during a manufacturing process. The release of the material is carried out by letting the retraction means apply a retraction force large enough to overcome the magnetic force between the fixing band and the substrate. The applied retraction force will then bring the fixing band into the rolled-up state. With this it has been found that the process time can be reduced significantly and that the material is fixed smooth but firm without damaging the material during the fixing or release.
Other presently preferred embodiments and further advantages will be apparent from the subsequent detailed description and drawings.

Brief Description of Drawings

For exemplifying purposes, the invention will be described in closer detail in the following with reference to embodiments thereof illustrated in the
attached drawings, wherein:

Fig. 1 is a perspective view of an apparatus for fixing a predefined length of a material, with a fixing band in a fixing state and a fixing band in rolled-up state on-top of a substrate;
Fig. 2 is a sectional exploded cross-sectional view of the fixing band along a longitudinal direction of the fixing band;
Fig. 3 is a sectional cross-sectional view of the fixing band along a longitudinal direction of the fixing band;
Fig. 4 is an exploded cross-sectional view of the fixing band along a transversal direction of the fixing band;
Fig. 5 is a cross-sectional view of the fixing band along a transversal direction of the fixing band;
Fig. 6 is a front view of the apparatus, in an embodiment with two fixing bands, where one of the fixing bands is in a rolled-up state and the other is in a fixing state;
Fig. 7 is sectional top view of a fixing band;
Fig. 8 is a side view of a fixing band in the rolled-up state;
Fig. 9 is a perspective view of an apparatus according to the invention, where the apparatus is used for manufacturing a screening device;
Fig. 10 is a perspective view of two fixing bands, in an embodiment where one of the fixing bands is equipped with a tool, more specifically a cutter; and
Fig 11 is a flow chart of a method according to the second aspect of the invention.

Description of Embodiments

In the figures of the drawings, embodiments of an apparatus for fixing a predefined length of a material according to the invention are shown.
Referring initially to Fig .1 which is a perspective view of an apparatus 1 comprising a pair of fixing bands 8, one fixing band 8 is shown in a fixing state and one fixing band 8 in a rolled-up state on top of a substrate 2. The two fixing bands 8 may be substantially identical or different from each other. Alternatively, only one fixing band may be provided, or more than the shown two. In addition to the fixing bands 8 and the substrate 2, the apparatus 1 comprises retraction means, not shown in Fig. 1.
The substrate 2 is preferably a planar substrate 2, but may in principle be shaped to the needs of the material that is to be fixed. In the following, reference is made to only one fixing band 8. The fixing band 8 has a first end 9 being located at one longitudinal end of the fixing band and a second end 10 located at the opposite longitudinal end of the fixing band. The fixing band 8 is preferably longer than at least the width of the material to be fixed, but may be shorter if sufficient fixing is still achievable. The fixing band 8 has a top side which when in the fixing state points away from the substrate 2 and a bottom side which when in the fixing state points towards the substrate 2.
The retraction means are configured to apply a retraction force on the fixing band 8. In the embodiment shown in the drawings, the retraction means comprises a string 7, see for instance Figs 2 and 3. The retraction force is applied at a proximal position to the second end 10 and directed towards the first end 9. The retraction means can release said retraction force when controlled to do so. The retraction means may be controlled automatically e.g. via a push button or a switch, or be controlled manually, e.g. via a lever or by directly retraction on the retraction means.
The fixing band 8 can be moved between at least two states, a fixing state and a rolled-up state. The fixing state is for fixing a material between the fixing band 8 and the substrate 2. In the fixing state the first end 9 and the second end 10 are fixed to the substrate 2 by a magnetic force. The fixing band 8 when in the fixing state is preferably parallel to the substrate 2 to achieve an even and uniform fixing of a material between the substrate 2 and the fixing band 8. The rolled-up state is for introducing a material onto the substrate 2, so that the material can be fixed between the fixing band 8 and the substrate 2, when the fixing band 8 moves to the fixing state. In the rolled-up state the fixing band 8 is preferably held coiled up by the retraction means applying a retraction force to the fixing band 8. The fixing band 8 can be moved from the rolled-up state to the fixing state by releasing the retraction force delivered by the retraction means, the release of the retraction force uncoils the fixing band 8, which is followed by the magnetic force retraction the fixing band 8 into the fixing state. The fixing band 8 can be moved from the fixing state to the rolled-up state by letting the retraction means apply a retraction force large enough to overcome the magnetic force between the fixing band 8 and the substrate 2, to bring the fixing band 8 to the rolled-up state. The first end 9 of the fixing band 8 may be fixed, the fixing can be carried out by gluing, screwing or nailing the first end 9 to the substrate 2, if needed other parts of the fixing band 8 may also be fixed to the substrate 2. The fixing band 8 may furthermore be fixed to the retraction means, or if other suitable fixing locations are available these may be chosen.
A flexible plate element 5 may also be connected to the fixing band 8 as shown Fig. 1, so that when the fixing band 8 is in the fixing state the flexible plate element 5 is located between the fixing band 8 and the substrate 2. The flexible plate element 5 may serve the purpose of giving a uniform contact surface, and/or protect the material to be fixed against dirt and/or prevent that the fixing band 8 leaves markings on the material to be fixed. The flexible plate element 5 may be made from a thin plate of steel, polymer or any other suitable material. It is also conceivable to form the flexible plate element as an active element by making the flexible plate element of spring steel. In the embodiment shown, the flexible plate element 5 is made of spring steel with a thickness of 0.4 mm. The flexible plate element 5 may be connected to the fixing band by glue, welding, soldering or by other attachments which leaves only blemishes on one side. In the shown embodiment two fixing bands 8 are shown, alternatively the apparatus may have only one fixing band 8 or a plurality of fixing bands 8. In the case where the apparatus 1 comprises two fixing bands 8, these may form a pair and be placed parallel to each other, though other constellations are easily imaginable, e.g. the fixing bands 8 being perpendicular or slanted relative to each other. The apparatus 1 may be customized for different purposes and materials, e.g. the apparatus 1 may be customized as a screening device adapted to work on screening material, the apparatus 1 would then further comprise a top element with a roller bar, a bottom element, and a screening body.
Referring to Figs 2 to 5, Fig. 2 is a sectional exploded cross-sectional view of the fixing band 8 along a longitudinal direction of the fixing band 8, Fig. 3 is a sectional cross-sectional view of the fixing band 8 along a longitudinal direction of the fixing band 8, Fig. 4 is an exploded cross-sectional view of the fixing band 8 along a transversal direction of the fixing band 8 and Fig. 5 is a cross-sectional view of the fixing band 8 along a transversal direction of the fixing band. The fixing band 8 comprises magnetic material 3, the substrate 2 also comprises magnetic material. In the embodiment shown, only the fixing band 8 comprises active magnets, whereas the substrate 2 is made from a magnetic material, here also designated 3. The magnetic material 3 of the fixing band 8 and the magnetic material 3 of the substrate 2 is configured to attract each other by magnetic force when the fixing band 8 is in the fixing state. The magnetic material 3 of the fixing band 8 and the magnetic material 3 of the substrate 2, may be in the form of permanent magnets, with the permanent magnet(s) 3 of the fixing band 8 being arranged to be attracted to the magnetic material 3 of the substrate 2 when the fixing band 8 is in the fixing state. Thereby, the fixing band 8 is fixed to the substrate 2 by a magnetic force when the fixing band 8 is in the fixing state. It may additionally or alternatively be said that either the substrate 2 or the fixing band 8 have one or more electromagnets, allowing for a controllable magnetic force between the fixing band 8 and the substrate 2.
The fixing band 8 may be formed from a plurality of units 4, as shown on Fig. 2. The units 4 being arranged transversally in the longitudinal direction of the fixing band 8, the units 4 within the plurality of units 4 are pivotally connected to each other. In this way, a bending connection is formed between the units 4. In the embodiment shown, the pivotal connection between the units 4 is achieved with bending hinges at the bottom of the units 4, for instance formed integrally by a material bridge. All the units 4 may comprise a permanent magnet, or only some of them, so that when the fixing band 8 is in the fixing state the permanent magnets comprised in the fixing band 8 are attracted to the magnetic material of the substrate 2. As a not-shown alternative to making the substrate a passive part of a magnetic material as described in the above, the substrate 2 may comprise an equal number of permanent magnets, where the permanent magnets comprised in the substrate 2 are arranged in a corresponding shape as the permanent magnets comprised in the fixing band 8 when the fixing band 8 is in the fixing state
The configuration of the fixing band 8 can be chosen in any suitable way. It is preferred that the cross-sectional shape is arc-shaped. The individual units 4 are formed such that the facing sides of neighbouring units are pressed against each other in the rolled-up condition. Since the diameter of the roll composed by the fixing band 8 when rolled up will increase, the gap between neighbouring units is made larger towards the end to ensure control of the movement.
The magnetic material 3 of the fixing band 8 may be accommodated in a recess in the fixing band 8, in the case where the fixing band 8 is formed by a plurality of units 4, each unit 4 of the plurality of units 4 may have a recess for accommodating the magnetic material 3.
In the embodiment shown, the cross-section of each unit 4 shown, is formed substantially as a wedge, in which the bottom of each unit is wider than the top of the unit. The wedge-shape delivers the advantage that it facilitates a roll-up of the fixing band 8 when a retraction force is delivered to the fixing band 8. As mentioned in the above, the retraction means comprises string 7 and suitable winding means (not shown) and the string 7 is attachable to the fixing band 8, preferably at the second end 10 of the fixing band 8.
In the shown embodiment the units 4 comprise a longitudinally through-going hole 6 and the string 7 is adapted to pass through the through-going holes 6 by providing the string 7 within the contours of the fixing band 8. This string arrangement is space saving and the amount of moving parts outside the fixing band 8 is minimized. Alternatively, to having through-going holes 6 through the units 4, each unit 4 may be equipped with loop or ring on top of it, allowing the string 7 to pass through there, making the design of the units 4 simpler.
Turning now to Figs 9 and 10, the apparatus 1 may further comprise a tool 12 adapted to perform work on material fixed by the apparatus 1. The tool may be a cutter for cutting the material fixed by the apparatus, a marking tool for marking the fixed material, a stamping tool for stamping the fixed material, or a paint tool for painting the fixed material, or tools for performing other operations. The fixing band 8 may be formed with a track 11 in the longitudinal direction of the fixing band 8. When the apparatus 1 comprises a tool, the tool may be in engagement with the track 11 and be adapted to travel along the track 11 and performing work on a material fixed between the fixing band 8 and the substrate 2. The tool can be mounted to move along the whole length or at least part of the length of the fixing band 8. The track 11 may be formed as longitudinal recesses in the fixing band 8, the recesses may be located on the sides of the fixing band 8, alternatively one or more recesses may form a track 11 in the top part of the fixing band 8, the track 11 may also not be formed by recesses, but can made by extra parts added to the fixing band 8, e.g. magnetic strips, or low friction hooks.
Such a configuration including a cutting tool 12 is particularly advantageous in a specific embodiment, in which a screening device having a screening body 13 and a roller bar 311 is to be manufactured by means of the apparatus. Thus, the apparatus furthermore comprises means 31 for holding the roller bar 311 and means 32 for supporting a roll of screening body cloth material. The relevant steps in the manufacturing of such a screening device will be described in detail below.
According to the invention, a method for fixing a predefined length of a material is provided. In Fig. 11 a flow chart of an embodiment of a method for fixing a predefined length of a material according to the invention is shown.
The first step 21 of the method is to provide an apparatus 1 according to the first aspect of the invention. It is preferable that the fixing band 8 is in the rolled-up state, though it is not strictly necessary to have the fixing band 8 in the rolled-up state as it can be rolled up from its unrolled state quite easily.
The second step 22 is placing a length material on the substrate 2 of the provided apparatus 1. In the above-mentioned embodiment suitable for the manufacture of a screening device, it is the cloth to form the screening body which is placed on the substrate 2. During this step, the cloth is unwound from the roll of cloth sitting on support means 32. The roller bar 311 is fastened to holding means 31 configured to hold the roller bar 311 in a manner which allows rotation of the roller bar 311. In order to provide the screening device with the desired length of the screening body 13, the upper edge of the length of cloth material is first fastened to the roller bar 311, for instance by an adhesive, following which the roller bar 311 is rotated on the holding means 31, for instance by means of a handle (not shown).
It may additionally or alternatively be said that if the apparatus 1 is light and small enough to be portable, or if the apparatus 1 can move the substrate 2 the substrate may be moved in contact with the material.
The third step 23 is fixing said material by bringing the fixing band 8 from the rolled-up state to the fixing state by releasing the retraction force delivered by the retraction means. The release of the retraction force may be done in a number of ways, e.g. the retraction means may be in the form of a pulley system with a string 7 attached to the second end 10 of the fixing band 8, in that case the pulley system might be controllable by a push button or a lever.
In an optional fourth step 24, work is performed on the fixed material. The work performed may be carried out by an operator of the apparatus 1 or if the apparatus 1 is provided with tools they may perform work on the material automatically, or the operator of the apparatus 1 may use the tools provided with the apparatus 1 to perform work on the material. In the embodiment in which the apparatus is configured to be used in the manufacture of a screening device, the cutter tool 12 is moved along the track 11 provided by the juxtaposed units 4 of the fixing band 8.
In an optional fifth step 25, the material is released. By letting the retraction means applying a retraction force large enough to overcome the magnetic force between the magnetic material of the fixing band 8 and the magnetic material of the substrate 2, the fixing band 8 is brought to the rolled-up state. Here, the section of the screening body 13 present between the section already rolled up on the roller bar 311 and the fixing band 8 is also rolled up on the roller bar 311, following which the screening device with roller bar 311 and screening body 13 may either be stored for further handling, or be subjected to further handling steps.
The invention is not limited to the embodiments shown and described in the above, but various modifications and combinations may be carried out. Embodiments of the invention have now been described. However, several alternatives are possible, as would be apparent for someone skilled in the art.

List of reference numerals

1: apparatus
2: substrate
3: magnetic material
4: unit
5: flexible plate element
6: through-going hole
7: string
8: fixing band
9: first end
10: second end
11: track
12: tool
13: screening body
21: first step
22: second step
23: third step
24: fourth step
25: fifth step
31: holding means
311: roller bar
32: support means

Claims

An apparatus (1) for fixing a predefined length of a material, the apparatus (1) comprising a substrate (2), preferably a planar substrate, a fixing band (8) and retraction means (7), in which the fixing band (8) comprises a first end (9) and a second end (10), the first end (9) being located at a longitudinal end of the fixing band (8) and the second end (10) being located at the opposite longitudinal end of the fixing band (8), the fixing band (8) being movable between two states, a fixing state in which the fixing band (8) is fixed to the substrate (2), the fixing state being intended for fixing the predefined length of a material between the fixing band (8) and the substrate (2), and a rolled-up state in which the fixing band (8) is rolled up from the fixing state, characterised in that
the fixing band (8) comprises a magnetic material (3), that
the substrate (2) comprises a magnetic material, and that
the retraction means (7) are configured to deliver a retraction force to the fixing band (8) in a longitudinal direction of the fixing band (8),
wherein the fixing band (8) in the fixing state is fixed to the substrate (2) by a magnetic force between the magnetic material (3) of the fixing band (8) and the magnetic material (3) of the substrate (2), and wherein in the rolled-up state the fixing band (8) is rolled up from the fixing state by allowing the retraction means (7) to apply a retraction force at the second end (10) of the fixing band (8) towards the first end (9) of the fixing band (8).
An apparatus (1) for fixing a predefined length of a material according to claim 1, wherein the magnetic material (3) comprised in the fixing band (8) and/or the magnetic material comprised in the substrate (2) are permanent magnets.
An apparatus (1) for fixing a predefined length of a material according to claim 1, wherein the fixing band (8) is formed by a plurality of units (4), the units (4) being arranged transversally in the longitudinal direction of the fixing band (8), the units (4) within the plurality of units (4) being bendingly connected to each other.
An apparatus (1) for fixing a predefined length of a material according to claim 3, wherein all the units (4) comprise a permanent magnet, and the substrate (2) comprises an equal number of permanent magnets, the permanent magnets comprised in the substrate (2) being arranged in a corresponding shape as the permanent magnets comprised in the fixing band (8) when the fixing band (8) is in the fixing state, so that when the fixing band (8) is in the fixing state the permanent magnets comprised in the fixing band (8) and the permanent magnets comprised in the substrate (2) attract each other.
An apparatus (1) for fixing a predefined length of a material according to any one of claims 3 or 4, wherein the cross-section of each unit (4) is formed substantially as a wedge having its longer dimension at the bottom.
An apparatus (1) for fixing a predefined length of a material according to any one of claims 3 to 5, wherein the plurality of units (4) are pivotally connected to each other via integrated hinges at the bottom of the units (4).
An apparatus (1) for fixing a predefined length of a material according to any one of the preceding claims, wherein the retraction means comprises a string (7) attachable to the fixing band (8), preferably at the second end (9) of the fixing band (8), the retraction means are arranged to pull said string (7).
An apparatus (1) for fixing a predefined length of a material according to claim 7 and any of claims 3-6, wherein the units (4) of the plurality of units (4) comprises a longitudinally through-going hole (6), the string (7) going through at least some of the through-going holes (6).
An apparatus (1) for fixing a predefined length of a material according to any of the preceding claims, the apparatus (1) further comprising a flexible plate element (5), the flexible plate element (5) being connected to the fixing band (8), so when the fixing band (8) is in the fixing state the flexible plate element (5) is located between the fixing band (8) and the substrate (2).
An apparatus (1) according to claim 9, wherein the flexible plate element (5) is made from spring steel.
An apparatus (1) for fixing a predefined length of a material according to any of the preceding claims, the apparatus (1) further comprising a tool (12), wherein the fixing band (8) has a track (11) formed in the longitudinal direction of the fixing band (8), the tool (12) being configured to be in engagement with the track (11) and adapted to travel along the track (11) and performing work on a material fixed between the fixing band (8) and the substrate (2).
An apparatus (1) for fixing a predefined length of a material according to any of the preceding claims, wherein the apparatus (1) comprises at least one pair of fixing bands (8), the fixing bands (8) within the pair being parallel to each other.
An apparatus (1) for fixing a predefined length of a material according to any of the preceding claims, wherein the first end (9) of the fixing band (8) is fixed.
An apparatus (1) for fixing a predefined length of a material according to any of the preceding claims, wherein the apparatus (1) is adapted for use in manufacturing a screening device (1) comprising a roller bar (311) and a screening body (13), wherein the predefined length of the material is a screening body cloth material, wherein the apparatus furthermore comprises means (31) for holding the roller bar (311), and means (32) for supporting a roll of screening body cloth material.
A method for fixing a predefined length of a material, the method comprising the steps of;
in a first step (21) providing an apparatus according to any one of claims 1 to 14, wherein the fixing band (8) is in the rolled-up state,
in a second step (22) placing said material on the substrate (2) of the provided apparatus, and
in a third step (23) fixing said material by bringing the fixing band (8) from the rolled-up state to the fixing state by releasing the retraction force delivered by the retraction means (7).
A method for fixing a predefined length of a material according to claim 15, the method further comprising the further steps of:
in a fourth step (24) performing work on the fixed material, and

in a fifth step (25) releasing said material, by letting the retraction means (7) apply a retraction force large enough to overcome the magnetic force between the magnetic material of the fixing band and the magnetic material of the substrate, so as to bring the fixing band (8) to the rolled-up state.