WO2020078645A1

WO2020078645A1 - A flat bed applicator arrangement and a method for use of a flat bed applicator arrangement

Info

Publication number: WO2020078645A1
Application number: PCT/EP2019/074863
Authority: WO
Inventors: Patrik Johansson
Original assignee: Cwt Worktools Ab
Priority date: 2018-10-17
Filing date: 2019-09-17
Publication date: 2020-04-23

Abstract

The invention relates to a method for and a flatbed applicator, comprising a table (2) and a roll (1) movably guided vertically and horizontally along the table (2) by means of posts (3), a horizontal guiding structure comprising fixed parallel profiles (40) attached to the table (2) and guide members (41) fixedly attached to a support structure (4) carrying each of said post members (3), each of said posts (3) including a vertically moveable support structure (34) and a vertical guiding arrangement (32) arranged to guide said vertically moveable support structure (34), said roll (1) comprising a fixed shaft (10) and coaxial shaft ends (10A, 10C) that are connected to said vertically moveable support stmcture (34), said fixed shaft (10) coaxially and rotatably supporting a cylindrical roll member (11, 100) with gables (110), and wherein a heating arrangement (120) is arranged within said cylindrical roll member (11, 100), wherein, said heating arrangement (120) comprises a heating rod (122) that forms a loop by means of having a first rod half (122 A) extending longitudinally within said cylindrical roll member (11, 100) on a first side of a centre plane (CP) including the centre axis (C) of said cylindrical roll member (11, 100) and a second rod half (122B) extending longitudinally within said cylindrical roll member (11, 100) on a second side of said centre plane (CP).

Description

A FLAT BED APPLICATOR ARRANGEMENT AND A METHOD FOR USE OF A FLAT BED APPLICATOR ARRANGEMENT

TECHNICAL FIELD

The present invention relates to a flatbed applicator, comprising a table and a roll movably guided vertically and horizontally along the table by means of posts, a horizontal guiding structure comprising fixed parallel profiles attached to the side edges of the table and guide members fixedly attached to a support structure carrying each of said post members,

each of said posts including a vertically moveable support structure and a vertical guiding arrangement arranged to guide said vertically moveable support structure and a power unit and actuator arranged to enable vertical movement of said vertically moveable support structure,

said roll comprising a fixed shaft and coaxial shaft ends that are connected to said vertically moveable support structure, said fixed shaft coaxially and rotatably supporting a cylindrical roll member with gables, and wherein a heating arrangement is arranged within said cylindrical roll member.

BACKGROUND ART

From W09853987 there is known a flatbed applicator using a traverse spanning the laying-out surface, which is passed in controlled manner over the laminating table, wherein a rotatable press roll arranged on said traverse, is applied under pressure to produce a desired laminate, wherein the flat bed applicator comprises a traverse spanning the laying-out surface, having linearly movable guided post comprising control and journaling means. However, such a design is both costly and complex, especially due to the use of a bulky traverse device.

From DE DE202010011881 there is known a flatbed applicator wherein the traverse device has been eliminated by means of separating the axis of the press roll from the actual roll and securing a shaft coaxial with the axis to the posts. However, the design suffers from insufficiencies regarding the need of synchronized control and the need of stable and precise control of the movement of the press roll.

There are also various known solutions regarding heating of rolls for laminating purposes, which suffer from one or more disadvantages, e.g. as shown in

US20140326415. SUMMARY OF THE INVENTION

According to one aspect of the present invention, one object of the invention is to provide an improved roll for a flatbed applicator, which is achieved with a flatbed applicator arrangement according to claim 1.

Thanks to the invention a high-quality lamination may be achieved due to providing good heat distribution and good temperature control ability. Further a cost-effective design may be provided which may also provide many other advantages, as may be apparent from the detailed description below.

According to further aspects of the invention:

said rod halves are positioned on a level underneath a horizontal plane including the centre axis of the roll, which provides the advantage that a more optimal distribution of heat may be achieved.

said rod halves are positioned at a distance in relation to the outer surface of said fixed shaft such that an air gap is achieved, wherein preferably said distance is at least of the diameter of said fixed shaft, which also may provide an advantage to achieve a more optimal distribution of heat.

said rod halves forming a loop having overlapping rod ends, which also may provide an advantage to achieve a more optimal distribution of heat, wherein preferably said rod ends include non-heated parts and that the overlap is positioned such that transition zones between heated parts and non-heated parts are positioned substantially in a common plane or with some distance apart said heating rod is secured to said fixed shaft by means of a plurality of holding devices, that may assist in providing a reliable solution

said gables comprise an inner part and an outer part, wherein said inner and outer parts are made from different material, which may facilitate a more reliable design, wherein preferably one of said parts is made in a material having substantially less heat conductivity than the other part and that the bearing is secured in said part having the lowest heat conductivity

said gables are maintained within pre-determined limits of said fixed shaft by means of abutments, preferably locking rings, attached to said shaft ends, preferably arranged to provide some space for thermal movement between the cylindrical roll member with gables and the fixed shaft, wherein preferably at least one of said abutments is in contact with a resilient pushing member arranged to push onto one of said gables to keep the roll urged against the other abutment, said cylindrical roll member includes a metallic cylinder made in a different material than said fixed shaft, which may provide advantages regarding ease of control, wherein preferably said cylindrical roll member also includes a resilient outer layer having a thickness that is larger than the thickness of said metallic cylinder.

BRIEF DESCRIPTION OF THE FIGURES

In the following the invention will be described more in detail with reference to the enclosed figures, wherein:

Fig. 1 shows a perspective view from above of a flatbed applicator according to a preferred embodiment of the invention,

Fig. 2 is a side view of the embodiment in Fig. 1 ,

Fig. 3 is a detailed side view of a chosen part of a preferred embodiment of the invention including the vertically moveable support structure,

Fig. 4 is a detailed view of the vertically moveable support structure,

Fig. 5 is a perspective view from above of an adjustable foot according to a preferred embodiment of the invention, and,

Fig. 6 is a side view of the foot in Fig. 5.

Figure 7 shows a longitudinal cross-sectional view of a novel roll design according to a preferred embodiment of the invention,

Figure 8 shows a perspective view of substantial parts of the inner of the roll according to the preferred embodiment of the invention, wherein the outer cylindric portion of the roll has been removed,

Figure 9 shows a transversal cross-sectional view through novel roll according to the invention,

Figure 10 shows a perspective view of an end part of the preferred embodiment according to the roll design,

Figure 11 shows a perspective view of a roll positioned in posts carried by a support member, provided with a novel function in the form of a drive unit that may provide autonomous movement of the roll,

Figure 12 shows the drive unit seen in a front view,

Figure 13 shows the drive unit in a side view,

Figure 14 shows the drive unit seen from above,

Figure 15 shows the drive unit in a perspective view from above,

Figure 16 shows a side view of the drive unit in active mode, Figure 17 is a view from above of figure 16, and

Figure 18 is a side view with the drive unit in inactive mode.

DETAILED DESCRIPTION

In Figs. 1 and 2 there is shown a side view and a perspective view of an arrangement according to the invention of a preferred embodiment. There is shown schematically a flatbed applicator table 2 being supported by a leg arrangement 21, preferably having remotely adjustable feet 9, as will be explained more in detail below. The leg arrangement 21 includes transversal support beams 211 and transversal feet beams 210. Further a roll holder 212, for an extra roll may be attached to the leg arrangement 21. Two longitudinal supporting beams 22 are attached underneath the table 2 adjacent each longitudinal side of the table 2. On to, preferably at the inside of, the longitudinal supporting beams 22 there are arranged two profiles 40 providing a fixed support for linear, horizontal movement of guiding members 41 for a support structure 4 carrying post members 3. The profiles 40 preferably have a C-shape, wherein the openings of the two profiles 40 are positioned facing each other. On each side there is preferably arranged a longitudinally distanced, pair of guide units, wherein each guide unit comprises two horizontally off set guide members 41, arranged to enable an adjustable clamping pressure within said profile 40.

On each side of the table 2 there is accordingly one such post member 3, which thanks to the support structure 4 and the guiding arrangement 40/41 is linearly, horizontally moveable along the table 2. Within each post member 3, there is arranged a vertically moveable support structure 34. Each vertically moveable support structure 34 supports one end 10 A, 10C of a shaft 10 that carries a roll 1. A motor 5 is arranged under the table 2, which via two shafts 6A, 6B (or alternatively one integral shaft) drives the vertically moveable support structure 34 for vertical displacement of the roll 1. As is evident the arrangement for moving and supporting according to the invention may be used in varying kinds of flatbed applicators, i.e. others than the one shown and exemplified herein.

A mechanical arrangement 31, 33 transmits the torque from the shafts 6A, 6B to each vertically moveable support structure 34. The roll 1 has an outer surface 11 intended to be in contact with an object (not shown) positioned on the upper surface 20 of the table 2 in connection with performing lamination. Each post 3 has a housing 30 that extends vertically upwardly from a bottom 35 and is arranged with a vertically extending slot 30A for through passage of the shaft ends 10A, 10C into the interior of the posts 3, thereby enabling vertical movement in relation to the table 2 and housings 30.

Further Figs. 1 and 2 shows that the upper end of each post 3 there are arranged handle means 36, to provide for easy movement of the roll 1 along the table 2. In a preferred embodiment there are multiple handles, e.g. a first handle 36A providing a vertically extending gripable part and one second handle member 36B providing a horizontally gripable part. In the preferred embodiment at least one activation device 37 is positioned nearby the handle device 36, to provide for easy activation of the motor 5, via a control unit (not shown) to either lift or lower the roll 1.

In Fig. 2 it is shown in detail that the support structure 4 includes a plurality of parts, that preferably are releasably attached to each other by means of screw nuts. Centrally there is one central part 44 that carries the motor 5 and also the gear reduction device 7. The central part preferably is in a form of a longish U-formed metal plate member having a substantial width to match the total length of the motor and the reduction gear device 7. The leg portions of the U-formed part are directed upwardly and sufficiently high to provide for appropriate strength and for attachment of further parts of the support structure 4. The second part 42 of the support structure has as its main purpose to carry the guiding members 41 that ran within the profiles 40 attached to the beam 22 underneath the table 2. These guiding members 41 are in a form of a plurality of low friction wheel members, as is known per se. The third part 43 forms the intermediate attachment between the central part 44 and the bottom part 35 of each post 3. This part 43 also serves as support for the mechanical arrangement 31, 33 that provides for the vertical movement of the roll 1.

In Fig. 3 it is shown that the mechanical arrangement 31, 33, for vertical movement, is in the form of splines 31, i.e. a pinion, interacting with a vertically extending dented rod 33, i.e. rack, that forms the lower part of each vertically moveable support structure 34. The upper part of each vertically moveable support structure 34 is formed by a resilient arrangement 8.

The resilient arrangement 8 is mechanically connected to the dented rod 33 and as a consequence connects each shaft end 10A, 10C with a dented rod 33. A control unit (not shown) provides for controlled activation of the shafts 6A, 6B via an activation device 37, (e.g. a touch pad) which in turn activates the mechanical arrangement 31, 33, causing lowering or lifting of the vertically moveable support structure 34.

From the output shaft 50 of the motor there is a reduction gear mechanism 7, preferably a worm gear, that reduces the rpm of the motor, in the range of 1/30- 1/100, preferably 1/40-1/60. The shafts 6A, 6B (or alternatively one integral shaft) preferably are hollow shafts, to provide reduced weight and also suitable diameter d, e.g. 20-30 mm, for the splines 31. The splines 31 preferably have an outer diameter D of about 25-30 mm and a pitch of about 4-6 mm. The splines 31 may either be integral with the shaft 6A, 6B or in the form of a bushing fixed to the end of each shaft 6 A, 6B.

As shown in more detail in Fig. 4 each resilient arrangement 8 comprises a rack member 80, a roll member 81 and a resilient member 82 in between them. The rack member 80 is, preferably adjustably, attached to the upper end part 330 of the dented rod 33. The upper end part 330 preferably is in the form of a threaded rod enabling adjustable fixation of the rack part 80 by means of nuts 331,332 fixing a bottom part 80A of the rack member 80. The rack member 80 has upwardly protruding wall parts 80B that protrude past the resilient member 82 and at the top a top part 80C forming an upper stop for the upper end 82A of the resilient member 82. The roll member 81 has an upper part 81 A comprising a roll attachment 81B for fixation of each roll shaft end 10 A, 10C. Downwardly protruding wall parts 81C protrude past the resilient member 82 and at the bottom a bottom part 81D forming a lower stop for the lower end 82B of the resilient member 82. Transversal guide members 83 interacting with vertical slits 84 safeguard a substantially rectilinear vertical movement relative to each other of the rack member 80 and the roll member 81.

The resilient member 82 is positioned between the two stop parts 80C, 81D in pretensioned manner to urge the rack member 80 and the roll member 81 to be positioned at a maximum distance apart in an unaffected mode. Preferably the tension is adjustable, e.g. by adjustment of the nuts 331,332 described above.

When the motor 5 is activated to lower the roll arrangement 1 the resilient arrangement 8 will be activated once the roll 2 gets into contact with the table 2, or an object on the table 2. The roll 1 will then transfer the load (due to contact) via its shaft ends 10A, 10C to the roll member 81, and thereby also to the lower end 82B of the resilient member 82, which will cause compression of the resilient member 82. Flence a resilient force/- pressure will be applied by means of the roll 1 onto the object/table 2. Preferably the resilient member 82 has a spring constant of about 500- 1500 N, more preferred 600- 1200 N.

The rubber material in the outer layer 11 preferably is arranged with a rubber composition in the range 40-55 shore A, which has proven to provide a high quality of the laminated products.

In Figs. 5 and 6 there are shown two views of adjustable feet 9 that may be attached to the leg arrangement 21 of a flatbed applicator, preferably to a transversal feet beam 210. As is evident it may be used in many different flatbed applicators, e.g. by use of adaptors and it is therefore foreseen that one or more divisional applications may be filed protecting the adjustable feet 9 as such. With reference to the flat bed applicator shown in Figs. 1 and 2 the feet 9 are used as replacement for the traditional feet shown in Figs, 1 and 2. The feet 9 comprise a bottom portion 90 that forms the support against a floor and a vertical support structure 91. The vertical support structure 91 is basically in the form of two parallel vertical plates 93, 94. Two horizontal support plates 95, 96 are arranged in-between the two vertical parallel plates 93, 94. Substantially centrally within these plates there are coaxial through holes 950, 960. A linear actuator 97 is arranged coaxially within the vertical member 91 and has its threaded part 970 protruding coaxially through each one of said holes 950, 960. A linear actuator nut 971 is arranged to move the plates 950, 960 up and down, depending on rotation of the screw 970. The horizontal plates 95, 96 are connected by means of vertical side plates 951, 952, which side plates keep the two plates 95, 96 at a constant distance.

Further guide members, preferably in the form of screws connecting the side plates 951 , 952 with the horizontal plates 95, 96, are arranged to be movable within a vertical slit 91 A, 91 B that is arranged substantially in the middle in in each one of the vertical plates 93, 94. A motor and reduction gear 99 provides rotation of the screw 97, such that a motorized adjustment of the height of the plates 95, 96 may be achieved. Attachment holes 953, 963 are arranged to fixedly attach a leg structure 21 of a flatbed applicator. In the embodiment shown in Figs. 1 and 2 it is the ends of the transversal leg beams 210 that will be attached by means of said through holes 953, 963, matching corresponding through holes adjacent each end of the transversal leg beams 210. By the use of a joint control unit (not shown) all motors 99 may be activated simultaneously to easily adjust the height of table 2.

Thanks to the arrangement according to the invention exemplified above numerous advantages may be achieved. The invention may be modified in many ways in relation to what is shown in figures without departing from the basic concept of the invention. For instance, it is foreseen that the motor for the roll height adjustment may be positioned differently, i.e. close to one side instead of the middle, and that more than one motor may be connected to provide the desired torque. Further, the skilled person realizes that different kinds of reduction gears may be used, e.g. a planetary gear, and also that that different kinds of mechanical transmission may be used, e.g. linear actuator mechanism driven by a worm gear by the shaft/s 6. Further, the skilled person realizes that different devices may be used to provide the resilient function, e.g. a rubber member or a blade spring, etc in place of a helical spring. Moreover, it is foreseen that many of the basic aspects of the invention may be fulfilled without any resiliency at all, i.e. a stiff connection of the roll to the vertically movable structure.

In figures 7, 8 and 9 there are shown figures of a novel roll 1 in accordance with a preferred embodiment according to the invention. As is evident the novel roll may be used in many different flatbed applicators and it is therefore foreseen that one or more divisional applications may be filed protecting the novel roll as such. The roll 1 comprises an outer layer 11 of resilient material, e.g. rubber. The tube formed resilient layer 11 is supported by a metallic cylinder 100. The metallic cylinder 100 is supported by gables 110 at each end. The gables 110 are rotatably supported by roller bearings 113 on a fixed shaft 10. The fixed shaft 10 preferably is tube formed and made of steel. The fixed shaft 10 supports a heating member 120, by means of holding members 128 attached to the fixed shaft 10. The gables 110 are axially locked onto the shaft 10 between two locking rings 131, 135. The fixed shaft 10 may be attached to a post member 3 by means of shaft attachment members 140.

As clearly shown in figures 8 and 9 the heating element is in the form of a longish heating rod 122 fixed to the shaft 10 by means of brackets 128. The heating rod 122 has been bent to form a loop that is positioned within the space between the outer surface of the fixed shaft 10 and the inner surface of the rotating metallic cylinder 100. Thanks to the loop one half 122 A of the heating rod 122 is positioned on one side of a plane PV passing through the centre of the fixed axis and a second half 122B is positioned on the other side of that plane. Preferably that plane PV is chosen to be vertical and the rod halves 122A, 122B are positioned symmetrically in relation to said plane. Further, as is noted the ends 122C, 122D of the heating rod 122 may overlap, preferably in the centre part of the roll 1. The reason for this is that each outer part at each end of the heating rod 122 of this kind does not supply heat. Accordingly, the overlap may preferably be positioned such that the heating ends 122E, 122F of the rod 122 will be positioned adjacent a common cross-sectional plane PP through the roll 1, which plane PP preferably is positioned substantially in the middle of the roll, axially. A temperature sensor 127 may preferably be positioned close to overlap plane PP.

As shown in figure 9, in the preferred embodiment a transverse line PS through the centers of the two rod halves 122A, 122B passes underneath the plane PC comprising the centre axis C of the roll 1. More preferred that line PS is positioned at a level that is in between a plane PC including the centre line C and a plane PT including the tangent of the outer surface of the fixed shaft 10. Such an arrangement implies that the curved parts 123G, that performs a l80-degree bend of the rod 122, will pass underneath the plane PT comprising the tangent, adjacent each gable 110. In an alternate embodiment the rod ends 122C, 122D may be positioned adjacent one gable 100.

There are contacts 125, 126 at each end 122C, 122D of the heating rod, for attachment of power supply.

Thanks to the invention beneficial distribution of heat will be supplied inside of the roll, such that the outer layer 11 may be provided with optimal heat that is substantially evenly distributed within the layer 11. Further, thanks to the precision that the inventive concept may provide regarding pressure, temperature, and speed it is foreseen that the control of the lamination process may be precisely controlled in accordance with pre-set requirements for a variety of different laminations processes and products. As is well known most manufacturers provide an optimal temperature, an optimal pressure, and optimal lamination speed to achieve the highest quality of the lamination. With the inventive concepts in combination with a control arrangement (e.g. software and appropriate electronic devices) the control unit operated by the operator may be pre programmed to push a certain button (or provide a command in any other appropriate manner) to thereby initiate a lamination process that will deliver pressure, temperature, and lamination speed in accordance with the recommended levels provided by the manufacturer. As a consequence, reliable production for producing high quality laminations may easily be provided.

An algorithm may be used to supply sufficient heat during the lamination process, by applying adapted amount of power to compensate for cooling during the travel of the roll along the laminating table, preferably thereby adapting in relation to a plurality of parameters sensed by appropriate sensors. In order to eliminate the needs of extra heat supply during the lamination process the roll may be designed to contain sufficiently large amount of heat, e.g. by means of relatively thick metal sleeve, such that the cooling during the laminating process may be neglectable. Of course, this is depended on the amount of heat that is absorbed by the product that is to be laminated, which is turn may be minimised by pre-heating the product. An example of sensors that may be used to control the process may be IR sensors.

To optimize, preferably the material in the metallic cylinder 100 is aluminum and of relatively large thickness t, in the range 5- 20 mm, more preferred 8- 15, since a large thickness assist to achieve even distribution and since aluminum has a high heat conductivity, i.e. above 200 W/mK, and has appropriate strength and relatively low weight. To further improve even distribution the thickness T of the outer layer 11 is at least as large as the thickness t of the metallic cylinder 100, preferably T>t. Further the diameter D of the metallic cylinder 100 (e.g. lOOmm < D < 200mm) is bigger than the diameter d of the fixed shaft 10, to provide sufficient space for the heating rod 122 in between their opposing surfaces 100A, 10D, preferably l0d>D>2d, more preferred 7d>D>3d. The heating rod halves 122A, 122B are preferably positioned out of contact with the fixed shaft 10, i.e. providing an air gap G them between, which may be in the region of 0,01-1 d. As already mentioned, the transverse line PS preferably is positioned off-center and below a horizontal centre plane PC at a level X in the range of 0 < X < 0,5D, which provides improved distribution due to heated air moving upwards, i.e. providing a good balance thanks to exposing the lower part of the metallic cylinder 100 with direct radiation heat than the upper part.

The gables 110 have bearings 113, preferably roller bearings, as low friction supports between the fixed shaft 10 and the cylinder support member 111, 112 of the gables 110. Preferably the cylinder support member 111, 112 include an inner part 111 and an outer part 112. The outer part 112 is fixedly attached to the metallic cylinder 100 and is arranged with an inner flange 112A for exact positioning of the inner part 111. A fixation plate 114, attached to the outer part 112, e.g. by screws 114 A, keeps the inner part 111 in place. The design also assists in easy assembly and also provides the possibility to use different materials in the parts 111, 112. Preferably the inner part 111 is in a material that is more resilient than the metals used in the fixed shaft 10 and the metallic cylinder 100, such that differences due to different heat expansions may be easily absorbed by the inner part 111, preferably E< 3000 MPa. Further, preferably the inner part 111 provides a relatively low heat conduction, e.g. l < 1 , which is fulfilled by some polymers, e.g. PTFE. Having low heat conduction in combination with positioning the bearing 113 in a groove 111 A adjacent the outer side of the inner part 111 may protect the bearing 113 from undesired heat exposure.

In Fig. 10 there is shown a suspension device 130, to keep the roll axially stable despite differences in heat expansion between the fixed shat 10 and the metallic cylinder 100. Such differences would result in a play occurring between the gables 110 and the bearings 113, if these were fixedly attached. However, thanks to enabling the bearings 113 to slide on the fixed shaft 10 such a play may be eliminated. This is achieved by means of the suspension device 130, which comprises two abutments 131, 135, preferably in the form of locking rings, fixed to each shaft end 10A, 10C and the use of a resilient device 132, preferably helical blade spring, positioned between each ring 131, 135 and each gable 110 that will push onto the inner ring of the bearing 113, such that the bearing is always fully in contact with the inner wall in the groove 11 A, whereby any play may be eliminated.

In figure 11 there is shown a perspective view of a roll assembly 1 for a flat-bed applicator having posts 3 and a support arrangement 4 carrying the posts 3. A drive unit 400 is attached to the support arrangement 4 which together with a drive belt 200, preferably dented, may provide for movement of the whole arrangement 1,3,4 along the table. As is evident the arrangement for moving the whole arrangement 1,3,4, according to this aspect of the invention may be used in other kind of applications where there is a need of controlled movement by means of a motor in at least one direction, than the one shown and exemplified herein.

The belt 200 is attached to the table 2 by means of attachment members 201, 202 at one end each of the table 2, which are schematically shown in figure 11. As is evident the belt 200 may be attached to the table 2 by means of many various devices, and is preferably easily detachable, at least at one end, to enable easy/quick demounting. The belt 200 is unattached between the attachment points 201, 202, such that the drive unit 400 may move along the belt 200 between the attachment points 201, 202, and thereby move the roll 1 on top of the table along the table 2.

The drive unit 400 comprises a fixed body member 410 and a pivotal body member 420. A first motor 430 with worm gear reduction 433 is attached to the fixed body member 410 on a first side to provide for pivotal movement of the pivoting body 420. A second motor 440 with worm gear reduction 443 is attached to a second side of the fixed body member 410 to provide for rotation of a drive wheel 441, preferably dented, that in contact with the belt 200 may move the arrangement 1, 3, 4 along the table 2.

In figures 12 to 15 it is shown a preferred embodiment of the driving unit 400. It is shown that the fixed body member 410 may be in the form of a U-shaped support member having a horizontal bottom and two vertical, parallel sides. At the outside of the vertical sides, on each side the motors 430, 440 are attached. Inside of the fixed body member 410 there is arranged the pivotal body member 420 pivotally attached onto a shaft 424 that is secured to the fixed body member 410. The pivotal shat 424 is positioned adjacent one end of the body members 410, 420. At the opposite end in relation to the pivotable shaft 424, the pivotal body member 420 carries two pressing wheels 421, 422. As is evident from figure 14 the pressing wheels 421, 422 are positioned such that they extend along a common line B with the belt 200 and positioned a distance T apart, such that when they are pressed downwards against the drive wheel 441 they will press the belt 200 into gripping contact with the drive wheel 441. As shown in Fig 14 a support wheel 428 for the belt 200 may be arranged onto the shaft 124. Optionally a further support wheel (not shown) may be arranged at the other end of the fixed body member 410, e.g. on a shaft 418,

Both of the motors 430, 440 are preferably electric motors and for driving a respective drive shaft 435, 443 there is arranged a worm gear reduction 433, 443, as is known per se. As output from the drive worm gear reduction 443 the shaft 442 drives the dented wheel 441, which is fixedly attached thereto. The shaft 442 is rotatably secured to the fixed body part 410. Preferably, the shaft 442 is arranged within a horizontal slot 411 on each side of the fixed body 410, e.g. to thereby providing an easy assembly of the shaft 442 with the drive wheel 441 into the fixed body 410.

For the pivotal body 420 there is arranged a pivoting mechanism 425, 432, preferably a lever mechanism, that is attached to the output shaft 435 of the pivoting motor 430, which hence may enable the pivotal body 420 to move between an active mode and an inactive mode.

In figures 16, 17 and 18 there are shown different views of the driving unit 400 when assembled together with the dented belt 200, in an embodiment without support wheels 428. In figure 16 there is shown an active mode, wherein the second motor 430 has pivoted the pivot body 420 downwards such that the drive belt 200 has been moved from its inactive position IA to an active position A, whereby the drive belt 200 is pressed onto the drive wheel 441 by means of the pressing wheels 421, 422, such that more than 90° of the periphery of drive wheel is in contact, preferably gripping, with the drive belt 200. Preferably the pressing wheels 421, 422 are arranged such that at least 120° of the drive wheel 441 is in contact with the drive belt 200. In figure 18 it is shown an inactive mode, wherein the pivotal body 420 has been pivoted into its inactive position whereby the drive belt 200, e.g. by inherent resiliency, has moved up to a higher level, IA, and thereby is positioned at a distance above the drive wheel 441, i.e. without contacting the drive wheel 441. At this position the lower surface of one of the pressing wheels 422 may be in contact with the drive belt 200, In a preferred embodiment the drive belt 200 is not pre-tensioned, i.e. attached without any substantial tension in an inactive mode, but instead a rather non elastic drive belt 200 may be used, due to the fact that the pressing action in active mode will provide for tensioning of the drive belt 200, and a fixedly positioned non elastic belt may be preferable, e.g. from a view point of position control.

From figure 17 it is evident that the pivotal body 420 preferably may assist in keeping the dented belt 200 in a correct position in relation to the dented wheel 441 and the pressing wheels 422, 421, which is achieved by providing the pivotal body 420 with vertical inner wall sides 426, 427 that will safeguard that the dented wheel will always be maintained within the space limited by those inner walls 426, 427.

As already mentioned, and shown in Fig 14, support wheels 428 for the belt 200 may be used. In some applications the preferred embodiment is to use support wheels 428 to keep the more part of belt 200 at a substantially stable level IA in both active and inactive mode, even if the belt 200 is without tension, i.e. the belt 200 is somewhat longer than the distance between the attachment points 201, 202. The support wheels 428 will then maintain the parts of the belt 200 on each side outside of the drive unit 400 at substantially the same level IA at all times. In active mode the pivotal body member 420, by means of the pressing wheels 421, 422, will then push the part of the belt 200 that is in between the support wheels 428 down on to the drive wheel 441, i.e. pushing a part of the belt 200 down to an active level A. The support wheel at the opposite end of the pressing wheels 421, 422 is preferably mounted on the shaft 424 that is also used as the pivoting axis for the pivotal body member 420. At the opposite end there is a separate shaft 418 attached to the fixed body member 110 to mount the other support wheel 424. Preferably the support wheels 428 have a width that substantially corresponds to the width of the belt 200 and have flanges protruding outside of the periphery of the support surface of the support wheels 428, to assist in keeping the belt in place. The drive unit 400 is not limited for use to flatbed applicators but may be used in connection with various kinds of applications. In that regard the table may be seen as a base for attachment of the belt and also forming the structure for movement of the movable arrangement carrying the drive unit. For instance, such a base could be a ladder and having a movable member guided along the ladder, e.g. a platform provided with wheels adapted for the ladder side beams, whereby there may be easily arranged a platform for transporting, e.g. building material, upwards along the ladder, and allowing gravity to return the ladder, by means of having the drive wheel 441 disconnected/non gripping from the belt 200.

Thanks to the design many advantages are gained. It is easy to install, also as a retrofit.

It is cost-efficient. The principle of de-coupling the belt 200 from the drive wheel 441 in inactive mode may provide many benefits, e.g. that a flexible choice between manual operation and motor driven operation is provided. Further, in applications with movements including height differences it provides the possibility of using gravity in de-coupled mode. It is evident for the skilled person that the basic principles of the invention may also be used in combination with a dented rack instead of a belt, i.e. a dented rack that is fixed, e.g. onto the lower side of the table of a flat-bed applicator, and then instead of pressing wheels in the pivoting body member have a dented cog wheel for interaction with the dented rack. Flence, the pivotal movement will then be inverted compared to what is described above.

The skilled person realizes that the drive unit 400 may be powered from the grid or by battery. If battery it may be an advantage to have it attached to the movable arrangement to eliminate moving cables.

Claims

1. A flatbed applicator, comprising a table (2) and a roll (1) movably guided vertically and horizontally along the table (2) by means of post members (3), a horizontal guiding structure comprising fixed parallel profiles (40) attached to the table (2) and guide members (41) fixedly attached to a support structure (4) carrying each of said post members (3),

each of said post members (3) including a vertically moveable support structure (34) and a vertical guiding arrangement (32) arranged to guide said vertically moveable support structure (34),

said roll (1) comprising a fixed shaft (10) and coaxial shaft ends (10A, 10C) that are connected to said vertically moveable support structure (34), said fixed shaft (10) coaxially and rotatably supporting a cylindrical roll member (11, 100) with gables (110), and wherein a heating arrangement (120) is arranged within said cylindrical roll member (11, 100), characterized in that,

said heating arrangement (120) comprises a heating rod (122) that forms a loop by means of having a first rod half (122A) extending longitudinally within said cylindrical roll member (11, 100) on a first side of a centre plane (CP) including the centre axis (C) of said cylindrical roll member (11, 100) and a second rod half (122B) extending longitudinally within said cylindrical roll member (11, 100) on a second side of said centre plane (CP).

2. A flatbed applicator according to claim 1, characterized in that said rod halves (122A, 122B) are positioned on a level (PS) underneath a horizontal plane (PC) including the centre axis (C) of the roll (1).

3. A flatbed applicator according to claim 1 or 2, characterized in that said rod halves (122A, 122B) are positioned at a distance (G) in relation to the outer surface (10D) of said fixed shaft (10) such that an air gap is achieved, wherein preferably said distance (G) is at least 10% of the diameter (d) of said fixed shaft (10).

4. A flatbed applicator according to any of claims 1-3, characterized in that said rod (122) forming a loop has overlapping rod ends (122C, 122D).

5. A flatbed applicator according to claim 4, characterized in that said rod ends (122C, 122D) include non-heated parts and that the overlap is positioned such that transition zones (122E, 122F) between heated parts and non-heated parts are positioned substantially in a common plane (PP) or with some distance apart.

6. A flatbed applicator according to claim 4 or 5, characterized in that said overlap is positioned adjacent longitudinal center of the roll (1).

7. A flatbed applicator according to any of claim 1-6, characterized in that said heating rod (122) is secured to said fixed shaft (10) by means of a plurality of holding devices (128).

8. A flatbed applicator according to claim 1, characterized in that said gables (110) comprise an inner part (111) and an outer part (112), wherein said inner and outer parts (111, 112) are made from different material.

9. A flatbed applicator according to claim 8, characterized in that one of said parts (111, 112) is made in a material having substantially less heat conductivity than the other part and that the bearing (113) is secured in said part having the lowest heat conductivity.

10. A flatbed applicator according to any previous claims, characterized in that said gables (110) are maintained within pre-determined limits of said fixed shaft (10) by means of abutments (131, 135), preferably locking rings, attached to said shaft ends (10A, 10C), preferably arranged to provide some space for thermal movement between the cylindrical roll member (11, 100) with gables (110) and the fixed shaft (10).

11. A flatbed applicator according to claim 10, characterized in that least one of said abutments (131) is in contact with a resilient pushing member (132) arranged to push onto one of said gables to keep the roll (1) urged against the other abutment (135).

12. A flatbed applicator according to any previous claims, characterized in that said cylindrical roll member (11, 100) includes a metallic cylinder (100) made in a different material than said fixed shaft (10) and preferably that said cylindrical roll member (11, 100) also includes a resilient outer layer (11) having a thickness (T) that is larger than the thickness (t) of said metallic cylinder (100).

13. A method for operating a flatbed applicator, said flatbed applicator comprising a table (2) and a roll (1) movably guided vertically and horizontally along the table (2) by means of post members (3), a horizontal guiding structure comprising fixed parallel profiles (40) attached to the table (2) and guide members (41) fixedly attached to a support structure (4) carrying each of said post members (3), each of said post members (3) including a vertically moveable support structure (34) and a vertical guiding arrangement (32) arranged to guide said vertically moveable support structure (34),

a power unit (5) and transmission (6A, 6B, 7) arranged to enable vertical movement of said vertically moveable support structure (34),

said roll (1) comprising a fixed shaft (10) and coaxial shaft ends (10A, 10C) that are connected to said vertically moveable support structure (34), said fixed shaft (10) coaxially and rotatably supporting a cylindrical roll member (11, 100) with gables (110), and wherein a heating arrangement (120) is arranged within said cylindrical roll member (11, 100), characterized by,

providing said heating arrangement (120) in the form of a heating rod (122) that forms a loop by means of having a first rod half (122A) extending longitudinally within said cylindrical roll member (11, 100) on a first side of a centre plane (CP) including the centre axis (C) of said cylindrical roll member (11, 100) and a second rod half (122B) extending longitudinally within said cylindrical roll member (11, 100) on a second side of said centre plane (CP).

14. A method for operating a flatbed applicator according to claim 13, characterized by having said rod halves (122A, 122B) positioned on a level (PS) underneath a horizontal plane (PC) including the centre axis (C) of the roll (1).

15. A method for operating a flatbed applicator according to claim 14, characterized by having said rod halves (122A, 122B) positioned symmetrically in relation to a vertical plane (VP) including the centre axis (C) of the roll (1).