Abstract:
For levelling webs of paper ( 3 ) gaps ( 20 ) are provided, each defined by a deflection roll ( 17 ) and a stationary bending face ( 16 ). For changing the wrap angle at the bending face ( 16 ) and also for non-bended passage of the web ( 3 ) through the device ( 1 ) the deflection roll ( 17 ) is transferable into varying positions powered by a positioning device ( 30 ). Thereby high speed operation with reliable function and simple construction are achieved.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a device with which flexural or elastic materials can be worked in achieving a desired non-stressed shape, such as a flat shape. Such materials may be substrates or other rollable materials having a constant thickness which are worked as individual sheets or as an endless material web. 
     2. Description of the Background 
     Due to it being supplied as a reeled material, for instance, paper tends to curl, i.e. a portion of the web spread out flat is subject to an inherent bending stress and thus tends to curve or curl to relieve the stresses on release of external forces. However, it may also be wanted to bend or work a flat layer which is planar when free of stress so that it assumes a curved position. In any case, bending breaks a predetermined stress by moving the material on its face to which it is to be curved relative to a bending face. In this arrangement the material defines an angle of wrap in the portion coming into contact with the bending face. This angle of wrap is determined by the position of a deflector or guide for the material next the bending face. This deflector may be provided upstream and/or downstream of the bending face. For modifying the angle of wrap or for optionally working both faces of the material the deflector arrangement and the bending face means are expediently adjustable relative to each other. For this purpose the bending face may be positioned on the device frame so that it can be adjusted relative to the deflector during the entire bending operation, e.g. to transpose material sections in sequence having continuously changing tendencies into the same, non-stressed planar shape or the like. Such an adjustment may, however, result in a bulky configuration involving complicated control and inertia in control movements which makes it difficult to quickly react to varying curl tendencies or other properties of the material. If the length of the material section tensioned freely or linearly between the bending face and the deflection face is greater than the deflection radius of the deflection face the aforementioned drawbacks are likewise given and in addition to this material section may oscillate at high running speeds to the detriment of consistent good quality working. 
     OBJECTS OF THE INVENTION 
     An object is to overcome the drawbacks of known configurations or of the kind described. A wide variety of stresses should be introduceable into the material by simple constructional means. 
     SUMMARY OF THE INVENTION 
     In accordance with the invention the guiding face forming the deflection face and the bending face define as boundaries a relatively narrow gap which permits material to pass preferably free of compression stress. The clear width or the like of the gap is variable so that its minimum width is many times smaller than the cited deflection radius when the material wraps the bending face. This width can be measured in an axial plane of the deflection passing through the center of the bending face or of the angle of wrap. The minimum width may also be smaller than half, a quarter or a tenth of the deflection radius or smaller than 50 or 30 times the thickness of the material so that the free running zone between the two guiding faces is maximally as large as the deflection radius or smaller as compared thereto corresponding to one of the cited values. 
     Although in this case too, the bending face is positionally adjustable during bending operation it is, however, particularly expedient when thereby only the deflection is adjusted transverse to the deflection axis since then the distances and time required maximally for positioning are relatively small. The deflection face can thus be set tangentially to the plane of a flank connecting to the bending face and the tangential point can be continuously displaced from a position remote from the flank and opposing the bending face up to the flank face and a zone behind the bending face. This is especially achieved when the associated positioning axis is located away from the deflection axes of the deflection face upstream or downstream next to the bending face and thus the gap width is slightly altered by the positioning motion. 
     A web of paper to be subsequently worked is expediently secured with its leading edge to the overlapping trailing edge of an advanced paper web, e.g. by an adhesive tape before these ends or the seam reaches the working station. If the seam is passed on an arc or angle of wrap through the working engagement at the bending face or the like it may easily tear. This is why the guiding faces are mutually displaceable in a sudden short impulse such that the seam can be guided past one or both guiding faces without curvature or even contact, thus excluding damage. 
     Although the device can be made for bending engagement only on one face of the material, it is expediently configured for alternating bending engagement on both faces. For this purpose two separate deflecting faces are displaceable in common and two separate bending faces are mutually and separately adjustable relative to the device frame. The deflecting faces provided for this purpose, on the one hand, and the bending faces on the other are facing each other and are minimally spaced from each other by a spacing which is maximally as large as the deflection radius or smaller. The deflecting faces may be formed by rotational faces or rollers, the clear width there between as measured in their common axial plane being smaller than their radius. At both deflecting faces and at the bending face the material may be simultaneously guided and thus curved alternatingly in opposite directions. 
     In accordance with the invention fluid or suction means is provided with which particles of dust, paper or the like can be permanently exhausted more particularly in the region of the guiding faces or gap. A suction port adjoining the gap or the guiding faces is shaped expediently, as viewed axially, other than circular, more particularly oblong so that in the associated gap boundary only a single suction orifice extending over the full gap length is necessary. Such a configuration is substantially simpler to produce than orifices arranged in a grid pattern. 
     The bending face is expediently arranged on a plate or slat-like or similar type reversible body which can be replaced as a module without needing to destroy any part of it or its fastener means and can be thus reinserted in reversed positions so that a further bending face of three, four or more such faces is in place for workingly engaging the material. Accordingly, these bending faces working alternatingly may be configured in one part. However, the bending face may also be formed by a rotational face, for example, a round rod, instead of an edged face. 
     To facilitate changing the bending body, together with a support body such as a rod, where necessary, its fastening to the device frame is suitable for radial removal, i.e. for removal transversely to the longitudinal direction of the bending face or to the width extension of the material. Removing or changing can thus also be done when the material regularly passes through the device, the same applying also to the deflector arrangement or the individual deflector bodies. 
     In a further aspect of the invention the guiding faces are slantingly adjustable relative to each other or relative to the material or the running direction or the like, more particularly as viewed at right angles to the longitudinal direction of the guiding faces so that varying wrap angles or gap widths can be achieved over the width of the material. This adjustment is possible during bending operation. 
    
    
     BRIEF DESCRIPTION OF THE INVENTION 
     Example embodiments of the invention are explained in more detail in the following and illustrated in the drawings in which: 
     FIG. 1 is a side view of a device for a multi-ply material web, 
     FIG. 2 is a partially sectioned view as seen from the right of a single subdevice of the arrangement as shown in FIG. 1, 
     FIG. 3 is a section through the bending tools as shown in FIG. 2, 
     FIG. 4 is a view of a bending body as shown in FIGS. 2 and 3, 
     FIG. 5 is a longitudinal section through the bending body as shown in FIG. 4, 
     FIG. 6 is a scrap view of the bending body as shown in cross-section in FIG. 3 on an enlarged scale, 
     FIG. 7 is a scrap view of the suction connection of the bending body, 
     FIG. 8 is a cross-sectional view of the mounting arrangement of one end of the bending body, 
     FIG. 9 is a cross-sectional view of the bearing means of the other end of the bending body, and 
     FIG. 10 is a scrap view of a further embodiment of the subdevice as shown in FIG.  1 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     As shown in FIG. 1 multiple equal bending or subdevices  1  are arranged in a station  2  horizontally juxtaposed and spaced from each other by an amount which is smaller relative to the space requirement for a device  1 , each of which is designed to work a separate material  3  in a working zone. In these working zones the materials  3  have parallel running directions  4  inclined downwards in running planes  5  parallel to each other. Each device  1  is arranged as a module for facilitated removal from a frame  6 . A multi-layer material web  7  from which the webs  3  located initially congruently on each other is fed horizontally and above the devices  1  to station  2  from separate reel stands, firstly aligned at a deflection  9  and then downstream thereof the individual materials  3  are each deflected in sequence from the web  7  at an upper deflection  8  and fed extended directly to the associated device  1 . From the working zone each material  3  is fed extended to devices  11  located below at which the materials  3  are placed one on the other in sequence to again form the web  7 . 
     In front and behind of the devices  1  the frame  6  comprises a portal  12  and  13  respectively each composed of rods, the vertical supports of these portals being connected to each other via horizontal girders  14  located on both sides of the material  3 . On their tops these members  14  mount the device modules  1  and can be removed together therewith as a unit from the remaining frame  12 ,  13 . The upper ends of portals  12 ,  13  are likewise interconnected with girders on which the deflectors  8  or rolls are rotatively mounted in sequence. 
     The single-layer material  3  is fed as an endless web to the working zone of the individual devices  1  via a cylindrical guide and deflection face  15  which the material  3  wraps over an angle of maximally 90°. From face  15  the material passes stretched directly to a guide or bending face  16  formed by a corner edge rounded in cross-section. Guide face  15  is formed by a rotating roll or deflector body  17  and the bending face  16  by a stationary bending body  18  comprising rectangular flat cross-sections throughout, which like deflector body  17  covers the full width of the material. Any soilage appearing in the working zone or in the vicinity of gap  20  is continuously removed pneumatically by a flow, for example by suction means  19 . The plane  10  of gap  20  slanting downwards in the direction  4  coincides with the bending flank of the bending face  16  which directly opposes guiding face  15  and is formed by an entirely planar larger face  21  of body  18 . The running plane  5  is steeper than face  21  so that the material  3  passes through the gap  20  from one gap boundary  15  to the opposite gap boundary  16  at an acute slanting angle before then being deflected on bending face  16  downwards and away from face  15  over an angle of less than 90°. The free length of material  3  between the two boundaries  15 ,  16  is extremely short, but continuously variable. This length is smaller than the largest cross-sectional extension of body  17  or  18  or is half or a quarter thereof. 
     Guiding face  15  is curved about a horizontal deflector axis  22 , oriented parallel to running plane  5  and at right angles to direction  4 . Bending face  16  is curved about a bending axis  24  orientable parallel thereto. The two convex curved faces  15 ,  16  greatly differ in their radius of curvature, the radius of face  15  being at least 10 to 20 times or 30 times larger than the radius of face  16 . Face  15  is adjustable about a positioning axis  25  oriented parallel to axis  22 , the positioning axis  25  being fixed on frame  6  and located on the side of axis  22  or of body  17  facing away from gap  20  or plane  10 . 
     The two ends of body  17  are secured or rotationally mounted on two supporting cheeks  26 , each of which is rotationally mounted about axis  25  over at least 120° or 360° with a bearing  28  and  29  respectively located at the corresponding outer side. Unit  17 ,  26 ,  27  can be radially removed from frame  6 , where necessary, together with bearings  28 ,  29 . For precise, continuous adjustment about axis  25  positioning means  30  are provided which comprise an upright rotational motor  31  and a gear such as an angular gear  32  directly flanged thereto. Gear  32  is secured to the upper side of one member  14  and operates self-locking. The corresponding cheek  26  is secured directly to the freely protruding output journal of gear  32  so that the latters gear bearing directly forms the corresponding sole bearing  28  for positioning unit  17 ,  26 ,  27 , eliminating the need for any further separate or frame-fixed bearing on this side. The positioning means  30 ,  40 ,  42 ,  43  or the suction means  19  may be arranged optionally on both sides of gap  20  by e.g. arranging gear  32  optionally on each one of members  14  and the connection  52 ,  53 ,  54 ,  55  optionally in the region of each one of members  14 . Due to this arrangement the operator side of the device  1  may be located optionally on either the one side or the other and, where necessary, maintained free of means  19 ,  30 ,  42 . 
     For adjusting unit  17 ,  26 ,  27  control means  33  are provided on the side of gear  32  facing away from this unit. Means  33  comprise a control cam  34  located in axis  25  of the journal and arranged directly on the other journal of the same gear shaft. The periphery of cam  34  acts on a sensor  35 , such as an inductive transducer, so that by setting a variable signal value the positioning means  30  is stopped when the corresponding position of guiding body  17  is attained. An analog indication of the position is provided by an optical display  36  on the outer side of the other bearing  29 . 
     The flat or rod-type body  18  having constant outer cross-sections full-length is secured replaceably to a rod or supporting body  37  which is larger in cross-section and which is cross-sectionally configured as a flat rectangular tubular body carrying intimately adjoined body  18  on one of its two wider outer faces. Due to this the edge faces of body  18  adjoining edges  16  are located in the planes of the two outer faces of body  37  which are narrower or located at right angles thereto. The ends of unit  18 ,  37 , more particularly only the ends of body  37  are rigidly connected with circular disk-shaped flanges  38  which are replaceably fixed to plate-shaped supporting flanges  38 ′ of frame  2  by axial bolts which can be screwed into place toward outside. Once the axial bolts have been released unit  18 ,  37  can be removed radially from supporting flanges  38 ′ or conversely reinstalled. 
     Face  16  is manually adjustable by positioning means  39  or  40  relative to unit  17 ,  26 ,  27  and frame  6  separately about two positioning axes  45 ,  46  located at right angles to each other, namely by the positioning means  40  during operation and by the positioning means  39  when operation is stopped. Axis  46  oriented parallel to face  16  and to axes  22 ,  25  is located on the side of face  16  facing away from gap  20 ,  10  roughly in the center axis of supporting body  37  or of the associated flanges  38 . For passage of the cited axial bolts these flanges  38  comprise slots curved about axis  46  so that the inclination of the face  16  and gap flank  21  can be steadily varied and then locked in place by clamping action of the axial bolts. The flank  21  is located in one position of unit  15 ,  26 ,  27  at right angles to the common axial plane  47  of axes  22 ,  25 , this axial plane intersecting flank  21  directly adjacent to face  16 . From this position planes  10 ,  47  can be steadily displaced in both opposing directions. Also so that plane  47  spacedly opposes face  16  and thus slants relative to plane  10 . In the cited center position the clear width of gap  20  is at a minimum, it increasing steadily when varied in both directions as is evident from the positions indicated dot-dashed in FIG.  3 . The minimum gap width is expediently more than one millimeter and less than three or five millimeters. Positioning movements of both positioning means  30 ,  39  result in such changes, it only being the positioning means  39  which establishes the smallest possible gap width. 
     Positioning means  40  permit mutually slanting adjustment of face  16  and axes  24 ,  46 , on the one hand, and of guiding face  15  and axes  22 ,  25  on the other. The cited gap width settings remain constant over the positioning length of positioning means  40 . Positioning means  40  set the one end, remote from positioning means  30 , of unit  18 ,  37  about positioning axis  25  whilst the other end of this unit merely privots about frame-fixed axis  45 , i.e. including the corresponding supporting flange  38 ′ in each case. Axis  45  is always located in the same axial plane of axis  25  and is laterally juxtaposed with the axial planes of axes  22 ,  24 ,  46  oriented parallel thereto. It is possible by the positioning means  30  to translate axis  22  also in this common axial plane. The supporting flange  38 ′ for the one flange  38  is adjustable by a guide  41  curved about axis  25 , this guide comprising a guide pin engaging a curved slot with zero diametral clearance and rigidly connected to supporting flange  38 ′. The mounting about axis  45  oriented transverse or inclined to flank  21  or plane  10  is formed by a joint  42  or a mount comprising a joining pin located fixed to frame  6  in axis  45 . 
     Each of the bearings  41 ,  42  comprises a mounting body  48  fixed to frame  6  laterally on the inside of the corresponding member  14 . The one mounting body carries guide  41  and the other, in a bifurcated arrangement, the joining pin which passes through the corresponding supporting flange  38 ′ between the forked arms of the corresponding mounting body  48 . After this adjustment the unit  18 ,  37  needs to be locked only in the region of guide  41  by suitable means  43 , for example by clamping. For this purpose a manually lever-operable clamping device is provided with which guide  41  can be axially tensioned relative to the corresponding mounting body  48 . To facilitate manual adjustment along the guide  41  the corresponding supporting flange  38 ′ is provided with a radially protruding handle  44  adjoining the inner side of this mounting body  48 . Clamp  43  is accessible directly on the underside of the corresponding member  14 . 
     Body  18  as shown in FIGS. 4 to  6  consists of an integral metal body the surface of which is coated overall or at least in the region of the four longitudinal edges  16  e.g. with a vacuum-deposited film of a harder substance, such as ceramic oxide film or the like maximally a tenth or half a tenth of a millimeter thick, for example. Body  18  is optionally turnable about its longitudinal center axis and about its transverse axis oriented at right angles thereto so that with respect to member  37  each of its four edges  16  can be optionally brought into the same working position for engaging the material  3 . For this purpose fastening means  49  for reversible tool  18  comprise on both flat sides of reversible bit  18  countersinks for fastener bolts with which tool  18  can be tensioned optionally with both flat sides against the corresponding flat side of member  37 . Edges  16  may have different radii of curvature so that one and the same tool  18  has working edges  16  for adapting to various working requirements. 
     Suction means  19  are stationary or not exposed to positional changes in operation and comprise a slot-shaped fluid or suction orifice  50  passing transversely through tool  18  in the middle between edges  16 . Opening  50  is oriented parallel to edges  16  and in line between countersinks  49 . The corresponding wall of member  37  is provided with a coincidental fluid orifice connecting the port of orifice  50  located in flank  21  to a flow passage  51 . Passage  51  is bounded solely by the inner sides of profile  37 , runs full length over the latter and has at one or both ends constricted connectors  52  which are provided for both gaps  20  at the remote outer sides of support flanges  38 ′ and laterally adjacent to  41  or axis  45 . To connectors  52  a flexible tube  53 , e.g. a hose, connects and traverses the underside of the corresponding member  14 . The other end of this tube is connected via a slanting connection  55  to a longitudinal passage  54 . Secured to the other longitudinal section of each member  14  is one such longitudinal passage  54 ! having a rectangular or square cross-section, into the side wall of which the connection  55  issues at an acute angle inclined to the flow direction in passage  54  to eliminate flow losses. The end of passage  54  located nearer to the frame part of deflector  9  translates via a bend into a passage  56  oriented vertically upwards, the upper end of which is connected to a suitable pressure/suction source, such as a blower. 
     As shown in FIGS. 1 and 2 only one single simultaneously effective tool edge  16  is provided for each working zone or device  1  so that tool engagement is possible on one face only of the corresponding material  3 . The configuration as shown in FIG. 3 is suitable for providing tool engagement optionally on both faces of the material  3 . For this purpose identical units  18 ,  37  are secured separate to the same support flanges  38 ′ on both sides of axial plane or axis  45  and adjustable about axis  46  independently of each other as as removable independently of each other. The working faces  16  of these two units spacedly oppose each other symmetrically to plane  45 . Flanks  21  are counter inclined so that their planes  10  are oriented at an obtuse angle in a V-formation to each other. Cheeks  26 ,  27  likewise support two separate deflecting faces  15 ,  15 ′ or identical deflection bodies  17  having separate deflection axes  22 ,  23  arranged symmetrically on both sides of an axial plane of positioning axis  25 . In one position this axial plane coincides with plane  45  so that the material  3  is able to pass from deflector  8  to deflector  11  without contact between rolls  17  and tools  18 , i.e. without being deflected in the working zone. By pivoting unit  17 ,  26 ,  27  in the one direction into the position as shown in FIG. 3 the material  3  is transferred from the deflection on one guiding face  15  with one material face into bending engagement of the other material face with the one bending face, namely the right-hand face  16 . By pivoting in the opposite direction the material  3  is correspondingly brought into engagement with the other bending edge  16  by the other deflection face  15 ′. 
     Due to pivoting about axis  25  the angle of wrap at the corresponding edge  16  can be varied dynamically and continuously during operation. Thereby the wrap angle at the corresponding deflection face  15 ,  15 ′ as well as the width of gap  20  are also changed. Gear  32  automatically locks each setting by the inner obstruction of its gear members. Independently of this, this wrap angle and gapwidth can be altered by positioning means  39 . In this respect also the two flanges  38  could be displaced relative to each other in torsional deformation of unit  18 ,  37  to achieve differing wrap angles along the length of edge  16 , as is possible by positioning means  40 . However, the dynamic variation is undertaken not with tools  18  but with deflections  17  resulting in a very simple configuration of the suction means  19 . Each passage  51  is connected to one of the connectors  52 . All subdevices  1  are connected to a common longitudinal header passage  54 . The cited ends of the two passages  54  are connected to the common riser passage  56  via the cited bend, configured as a Y-connector. Since the deflectors  17  cannot come into contact with tools  18  or other components of the device  1  even when fully rotated about axis  25  no means for restricting travel such as limit switches are needed. Each tool  18  or the tool edge  16  thereof may also be replaced by a rotating rod, the bearings of which are to be flanged to the support flanges  38 ′ or provided on flanges  38 . All components are located freely accessible thus greatly facilitating maintenance or insertion of the material  3 . 
     As shown in FIG. 3 on the side of the deflector  17  facing away from tool  18 , namely between deflectors  8 ,  17  or  11 ,  17  a further material guide  57  may be provided located nearer to deflector  17 . Guide  57  does not deflect during bending but when the material  3  is guided past without contacting bending face  16  or at the most slightestly touching it. For each deflection face  15 ,  15 ′ material guide  57  comprises a corresponding frame-fixed deflector  58 ,  58 ′ or cylindrical rod or the like. In one position deflection face  15  forms with deflector  58  a tight passage gap for S-shaped reversing deflection of the material  3  and in the other position for likewise oppositely deflecting in the region of an equal deflector gap between deflection face  15 ′ and deflector  58 ′. The material passes through the deflection gap in each case without any clamping pressure so that only one material face has deflector contact at any moment. Deflectors  58 ,  58 ′ are secured to flanges  59  and thus secured adjustable and removable at a support flange  59 ′ as already described with respect to flanges  38 . Accordingly, here too, positioning means may be provided corresponding to means  39 ,  40 , the deflectors  58 ,  58 ′ like the deflectors  16  each being located eccentrically to the corresponding positioning axis. 
     In the embodiment shown in FIG. 10 the deflectors  17  are provided spacedly downstream of bending faces  16  and deflector  8  is located upstream of faces  16  as shown in FIG.  1 . To engage and disengage passage control mode for non-worked passage of material  3  past the faces  16  the drive  31  is a power of fluid cylinder. Drive cylinder  31  comprises two separate cylinders each separately controllable and rigidly connected to each other in series. The pistons rods face away from each other. Each cylinder can be transposed separately into two end positions so that four stop-limited working strokes, namely that of each individual cylinder and the two working cylinders are achieved. Instead of the deflectors  17  being fixedly mounted to the frame the units  18 ,  37  or the supporting flange  38 ′ are pivoted about axis  25  of deflector  8  by drive  31 . Thereby each of the two tools  18  too, can optionally be brought into engagement with the material  3 . Fine adjustment of the tool  18  or of its wrap angle is done manually via gearing such as a worm gear.