Abstract:
A device for isolating strips conveyed next to another in lengthwise direction is constituted by at least one separating unit which is extended parallel to a lengthwise axis. Each strip is assigned to one guide and it is inserted and guided by the guides in a plane running essentially parallel to the lengthwise axis of the separating unit and different for neighboring guides. When the strips are inserted into the guides, the guides are adjustable from a starting position, in which the strips have a slight lateral interval, into a separable position, in which a larger interval exists between the strips.

Description:
BACKGROUND OF THE INVENTION 
   The present invention relates to a device for isolating strips, particularly metal strips, conveyed next to one another in their lengthwise direction. These types of devices are used in order to produce a defined horizontal interval between the strips, with which the strips may be fed to further processing. In this way, damage of the strip edges is avoided, which otherwise could be caused by contact between the strips conveyed next one another. 
   The isolation has particularly significance in the production and processing of metal strips, which are obtained, for example, from a wide metal band by slitting using slitting shears and are subsequently coiled into isolating coils in a coiling device. These types of strips made of metal have a high intrinsic stiffness transverse to the direction of conveyance even if they have a slight thickness. On the one hand, this intrinsic stiffness makes the production of an interval between the individual strips transverse to the direction of conveyance more difficult. On the other hand, due to the intrinsic stiffness of the strips, even slight contacts between the strips may lead to significant damage. 
   The separation of metal strips is made more difficult if the isolation of the strips is to occur a short distance after the slitting shears. In this case, which occurs frequently due to the overall space available, which is often restricted in practice, the strips which are still connected to the uncut sheet endeavor, due to their intrinsic stiffness, to maintain their original direction of conveyance, so that greater forces have to be applied for the separation. 
   If, in contrast, the isolation is first performed at a large distance from the slitting shears, the connection to the still uncut sheet does not have such a strong effect. Instead, the danger arises that the strips will run uncontrolled out of the intended direction of conveyance. 
   In practice, separating devices whose guideways are delimited by separation disks which are fixed in their position are used as a rule. The strips are typically laid by hand into these guideways. Alternatively, isolating the strips through a mechanically-generated, back and forth shaking movement of a separating shaft has also been attempted. 
   Manual isolation, particularly in the separation of strips made of metal, not only requires great bodily exertion, but also has the danger of injuries. In mechanically-supported isolation, it has been shown that the isolation result of the mechanical back-and-forth movement of the strips is so unreliable that the position of the strips must be corrected by hand. The latter particularly applies for large band thicknesses, in which the intrinsic stiffness of the metallic strips is particularly noticeable. 
   A device for a separating the front ends of strips produced from a metal band by slitting is known from German Published Application 21 38 088, in which the isolation of the strips is performed using an automatically operating isolating unit. For this purpose, the isolating unit is equipped with clamping devices which are displaceable on a joint axis, to each of which one strip front end is assigned. After the strip front ends are clamped in the clamping devices, the clamping devices are simultaneously displaced on the axis, so that the strip front ends are spread apart from one another like a fan. The movement of the clamping devices along the axis is coordinated in this case via threads having different pitch in such a way that all strip front ends reach their separated positions simultaneously. 
   The advantage of the known device described above is that it allows automated isolating of the strips within a short operating interval. However, it is disadvantageous that for this purpose a significant constructive outlay is necessary, particularly for the clamping devices. In addition, as a rule the strip front ends may only be laid in the clamping devices when the device is at a standstill. In addition, the known device requires a significant amount of space, which in many cases may only be made available with difficulty. 
   SUMMARY OF THE INVENTION 
   The object of the present invention is to provide an isolating device of the type described above which is constructed simply and allows reliable, time-saving isolation of the strips. In addition, advantageous uses of such a device are to be indicated. 
   This object is achieved by a device for isolating strips, particularly metal strips, conveyed next one another in their lengthwise direction, having at least one separating unit extending in an axial direction, in which each strip is assigned one guide, each of which guides one of the strips, which are positively inserted into them, in a different plane running essentially parallel to the lengthwise axis of the separating unit than each of the guides positioned neighboring it, the guides, when strips are inserted in them, in addition to having a starting position, in which the strips have a slight lateral interval, being adjustable into a separating position, in which there is a greater lateral interval between the strips. 
   In a device implemented according to the present invention, it is no longer necessary to clamp the strips into the separating unit for the isolating procedure. Instead, the strips are positively guided in guides. Simultaneously, the guides are implemented in such a way that strips positioned neighboring one another each lie in different planes. In this way, lateral contact of the strips and the danger of damage accompanying this is avoided from the outset. In addition, the guides are adjustably implemented in such a way that the strips may be brought from a starting position, in which they have a slight lateral interval in relation to a plane running parallel to the lengthwise axis of the separating device, into a separating position, in which this interval is increased to the size necessary for further processing. At the same time, the guides hold the respective strips lying in them so tightly enclosed that they are reliably positively guided, at least on their edge regions. 
   The positive guiding of each of the strips in a different plane which is provided according to the present invention allows, at the same time, the strips to be held loosely in the guides of the separating unit without the effect of clamping forces. In this way, the front ends of the strips may be pushed into the separating unit without the production cycle having to be interrupted. Thus, during the processing of strips made of metal, bringing the slitting shears to a standstill for inserting and clamping the strip front ends in the separating device is no longer necessary. 
   A further essential advantage of the embodiment of a separating device according to the present invention is that high lateral forces may be applied via the guides onto the strip front ends loosely inserted in them during the separating procedure performed by the adjustment of the guides. In this way, the present invention also allows reliable isolating of metal strips which have a greater thickness and high intrinsic stiffness. 
   In practice, the present invention may be implemented simply if two planes are provided, in each of which strips are guided, and one of the guides at a time guides the strip assigned to it in one plane, while the guide closest neighboring this guide in the axial direction of the separating unit guides the strip assigned to it in the respective other plane. In a device designed in this way, two different conveyor planes are selected, to which the strips, viewed transverse to their direction of conveyance, are each assigned in alternating sequence. This allows reliable separation of the strips to be performed in a simple construction of the device. 
   According to a further embodiment of the present invention, the separating unit may include two rotatably mounted shafts having their axes positioned in parallel, between which the strips are guided, the guides for the strips being implemented on the respective shafts and running around the circumference of the shafts. In this embodiment, the circumferential surfaces of one shaft each form a cover of the open side of the guides implemented on the respective other shafts. In this way, a guide gap is formed for each strip between the shafts, in which the strips are reliably guided. The danger of the strips breaking out of the guides due to twisting or similar things is therefore excluded. 
   In this context, it is particularly advantageous if the guides are implemented like sections of thread, each having a pitch, and the shafts are driven in opposite directions. In a device according to the present invention designed in this way, the strips may be moved into their isolating positions by rotation of the shafts and/or the respective guides assigned to them. It is particularly advantageous in this regard if, starting from a first guide having the smallest pitch, the pitch of each following guide in the axial direction of the shafts is greater than the pitch of the closest neighboring guide to it in the direction of the first guide. This allows the strips to be brought, according to the pitch of the respective guide assigned to them, from a starting position to their final isolating position using one single rotational movement of the shafts. In this case, because the pitches of the successive guides in the axial direction of the shafts each increase in relation to the one preceding, consideration is given to the circumstance that the amount by which the strips are each displaced from the non-separated position transverse to their direction of conveyance must also increase with increasing distance of the strips concerned from the strip displaced least, which is selected as a reference point, in order to obtain a uniform interval of the strips upon termination of the separation. 
   An advantageous variant of the present invention is characterized in that the guides of the separating unit are implemented on isolating segments. In this embodiment, the strips are brought in guides, from the starting position into the separated position by elements which are positionable independently from one another. In this case, the guides present on the isolating segments are again implemented in such a way that the strips positioned neighboring one another are each conveyed into different planes. 
   An expedient alternative for using rotationally operated shafts in this contexts is that the isolating segments are implemented in the form of sliding blocks and are movably guided in the axial direction of the separating unit. The particular advantage of the use of the sliding blocks guided in this way is that relative movements between the strips and the contact surface of the respective guide assigned to them during the separating procedure may be largely avoided. Large adjustment paths may be made possible with simultaneously simplified construction and a low space requirement of the drives required for the adjustment if the isolating elements are distributed onto different guideways. 
   In addition, it is expedient if the separating unit has a first operating position, in which the strips lie loosely in their guides, and a second operating position, in which the strips are clamped in the guides. This embodiment of the present invention allows the strip front ends to be pushed loosely into the separating device without loss of time and subsequently to be clamped in the guides. This is advantageous, for example, if the separating device according to the present invention may travel from an initial position, in which the strip front ends are pushed in, into a transfer position, in which the strips are, for example, transferred to a coiling device. The loose strip front ends, which are positively guided only during the pushing-in procedure, may be reliably fed to further processing in this way, it also being possible to perform the separation during the transfer procedure. 
   The danger of damage to the strips, particularly to their edges, may be avoided if the free edges of the guides are rounded or flattened, at least in the region in which they come into contact with the strips. If the guides are implemented as thread sections, it is favorable if the angle of the rounding or flattening is adjusted to the respective pitch of the thread section in such a way that an essentially exclusively linear contact between the strips and the free edges occurs. By dimensioning the free edges in this way, damage to the strip edge or surface by edges of the guides which cut into the strips may be reliable avoided. 
   The present invention allows safe, reliable isolation of strips with a low outlay for apparatus and little building material. At the same time, a device according to the present invention is, due to the simplicity of the construction of the separating unit, particularly suitable for automatic adjustment to various operating conditions, such as those which occur, for example, upon a change of the widths of the strips to be processed. 
   A first advantageous use of a device according to the present invention is for such a device to be in the outlet of a device for slitting a band, particularly a metal band, into multiple strips conveyed next one another in the lengthwise direction. In this case, depending on the construction conditions and the requirements which result from the type of further processing of the strips, the isolating device may be positioned stationary. It may also be expedient, however, if the device for isolating the strips may travel from a transfer position, in which it accepts the strips to be isolated, into an isolating position, in which the isolating of the strips occurs. 
   Furthermore, a device according to the present invention may also be advantageously used for transporting strips, particularly metal strips, using which the strips are transported from a device in which the strips are produced by slitting a band to a device in which further processing of the strips occurs. 

   
     BRIEF DESCRIPTION OF THE DRAWING 
     In the following, the invention is described in more detailed with reference to a drawing illustrating an exemplary embodiment. 
       FIG. 1  shows, in a frontal partial view, a pair of shaft used in a device for isolating metal strips in a first operating position, 
       FIG. 1   a  shows, in a frontal partial view, an enlarged detail A of  FIG. 1 , 
       FIG. 2  shows, in a frontal partial view, the pair of shafts shown in  FIG. 1  in a second operating position, 
       FIG. 3  shows a device for slitting a band, a device for transporting the strips, a device for isolating the strips and a device for further processing of the strips. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 3  shows a device A for slitting a band Y, a device B for transporting the strips S 1 -S 12  from the device A, a device B 1  to isolate the strips S 1 -S 12  and a device C in which further processing of the strips S 1 -S 12  takes place. 
   Separating unit N illustrated in the figures, which is made of two shafts  1 ,  2 , is a part of a further device, not shown, for horizontal isolating of strips S 1 -S 12 , which are produced by slitting a steel band, not shown, in slitting shears, also not shown. 
   The device for isolating strips S 1 -S 12  is, for example, positioned in the outlet of the slitting shears. 
   Alternatively, it may also be positioned on a transfer device, not shown. Using such a device, the front ends of strips S 1 -S 12  may be transferred into a coiling device, not shown, in which they are wound into coils. The advantage of this design is that the time necessary for the transfer may be used for separating strips S 1 -S 12 . 
   Each of shafts  1 ,  2  is equipped on one half, shown in  FIGS. 1 ,  2 , with isolating segments V 10 -V 110  and/or V 20 -V 210 , which are pushed onto respective shaft  1  or  2  in succession in axial direction X and are connected to appropriate shaft  1 ,  2  via suitable attachment elements, not shown, so they are removable and rotate with the shaft. The interval in axial direction X between individual isolating segments V 10 -V 110  and/or V 20 -V 210  is fixed in this case by spacers  3 ,  4 . A corresponding number of isolating segments V 10 -V 110  and/or V 20 -V 210 , not shown, is positioned in the same way on the other half of shafts  1 ,  2 . 
   The advantage of equipping shafts  1 ,  2  using isolating elements V 10 -V 110  and/or V 20 -V 210  in the way described, using spacers  3 ,  4 , is that isolating elements V 10 -V 110  and/or V 20 -V 210  of the type may be precisely premanufactured as independent components at low cost and manually or automatically attached to shafts  1 ,  2  according to the current strip program. In this case, it is particularly advantageous if isolating segments V 10 -V 110  and/or V 20 -V 210  are removably connected to shaft  1 ,  2 . This allows separating unit N to be adjusted to changed widths of strips S 1 -S 12  within a short time. The latter particularly applies because, due to the removable attachment, the interval of isolating elements V 10 -V 110  and/or V 20 -V 210  may be adjusted easily. If the respective distance between isolating elements V 10 -V 110  and/or V 20 -V 210  is fixed by spacers  3 ,  4 , it is also ensured that, even in the event of the occurrence of high lateral guide forces in the course of the separation, reliable, exactly positioned isolation of the strips S 1 -S 12  is performed. 
   Each isolating segment V 10 -V 110  and/or V 20 -V 210  has a first radial circumferential contact surface  5 , which is delimited on one side by a free radial circumferential edge  6  of respective isolating segment V 10 -V 110  and/or V 20 -V 210 . In this case, isolating segments V 10 -V 110  and/or V 20 -V 210  are each positioned in pairs P 10 -P 14  and/or P 20 -P 24  in such a way that free edges  6 , which laterally delimit first contact surfaces  5  of isolating segments V 10 -V 110  and/or V 20 -V 210  assigned to respective pair P 10 -P 14  and/or P 20 -P 24 , are assigned to one another. 
   On its other side, first contact surface  5  of isolating segments V 10 -V 110  and/or V 20 -V 210  is delimited by a lateral wall  7  of a circumferential collar  8 . In this case, in each of pairs P 10 -P 14  and/or P 20 -P 24 , lateral walls  7  of isolating segments V 10 -V 110  and/or V 20 -V 210  assigned to respective pair P 10 -P 14  and/or P 20 -P 24  lie opposite to one another and have a parallel course implemented like a screw thread, lateral walls  7  of isolating segments V 20 -V 210  assigned to shaft  2  being implemented in the opposite direction to lateral walls  7  of isolating segments V 10 -V 110  assigned to first shaft  1 . 
   In this way, lateral walls  7  and first contact surfaces  5  of isolating segments V 10 -V 110  and/or V 20 -V 210 , which are each assigned to one of pairs P 10 -P 14  and/or P 20 -P 24 , each form a guide F 10 -F 14  and/or F 20 -F 25 , each of which has its own pitch s 10 -s 14  and/or s 20 -s 25 , which differentiates it from each other pitch s 10 -s 14  and/or s 20 -s 25  of respective other guides F 10 -F 14  and/or F 20 -F 25 . 
   In the region of collar  8 , isolating segments V 10 -V 110  and/or V 20 -V 210  has a diameter D 1 , which is greater than diameter D 2  of isolating segments V 10 -V 110  and/or V 20 -V 210  in the region of first contact surface  5 . The circumferential surface of collar  8  forms a second radial circumferential contact surface  9 , through which respective strip S 1 -S 12  is held in guide F 10 -F 14  and/or F 20 -F 25  implemented on respective opposing shaft  1  and/or  2 . 
   In this way, strips S 1 -S 12  are guided between shafts  1 ,  2  in alternating succession in conveyor gaps R 10 , R 20  in two planes of conveyance E 1 , E 2 , which run parallel to rotational axes W 1 , W 2  of shafts  1 ,  2  and lengthwise axis L of separating unit N, which also runs parallel to these rotational axes W 1 , W 2 . In this case, guides F 10 -F 14  of shaft  1  guide strips S 1 , S 3 , S 5 , S 7 , S 9 , S 11  assigned to plane of conveyance E 1 , while guides F 20 -F 25  guide strips S 2 , S 4 , S 6 , S 8 , S 10 , S 12 , which are assigned to second plane of conveyance E 2 . 
   Free edge  10  between each lateral wall  7  and contact surfaces  9  assigned to this wall  7  is provided with a phase in the form of a flattening ( FIG. 1   a ). This prevents the free edge, which would otherwise be sharp, from cutting into respective strips S 1 -S 12  due to the lateral forces applied in the course of the separating procedure. 
   Pitches s 10 -s 14  and/or s 20 -s 25  of guides F 10 -F 14  and/or F 20 -F 25  increase, starting from guide F 10  and/or F 20  positioned closest to shaft center  1   a  of shafts  1 ,  2 , in the direction of respective shaft end  1   b,    2   b.  Thus, for example, guide F 11  has a smaller pitch s 11  than guide F 12 , positioned closest neighboring to it in the direction of shaft end  1   b.  In the same way, pitch s 21  of guide F 21  is larger than pitch s 20  of guide F 20 , which is its closest neighbor in the direction of shaft center  1   a.  Simultaneously, pitch s 20  of guide F 20  is smaller than pitch s 10  of guide F 10  of shaft  1 , which is positioned nearer shaft end  1   b,  which in turn is smaller than pitch s 21  of next following guide F 21  of shaft  2  in the direction of shaft end  1   b,  etc. The amount by which pitches s 10 -s 14  and/or s 20 -s 25  of guides F 10 -F 25  each increase in relation to respective next smaller pitches s 10 -s 14  and/or s 20 -s 25  is uniform. In this case, the increase of the thread pitch of individual guides F 10 -F 25  in relation to respective closest neighboring guide F 10 -F 25  is selected in such a way that, starting from the initial position, the desired interval between strips S 1 -S 12  is achieved in the separated position at maximum rotational setting of shafts  1 ,  2 . 
   Shafts  1 ,  2  are rotatably mounted in opposite directions in bearings, not shown, for this purpose and may be transferred, using a drive, also not shown, from their first operating position, illustrated in  FIG. 1 , in which strips S 1 -S 12  are not isolated, into the second operating position, shown in  FIG. 2 , in which strips S 1 -S 12  are located in their separated position. In this case, the direction and speed of rotation of shafts  1 ,  2  during the separating procedure is tailored to the direction and speed of conveyance of strips S 1 -S 12 , so that the relative speeds arising are reduced to a minimum. 
   Using drives, also not shown, shafts  1 ,  2  may be moved away from one another in the radial direction for insertion of the front ends of strips S 1 -S 12 . Their axial interval may also be changed in such a way that strips S 1 -S 12  are clamped in guide gaps R 10 , R 20 . 
   If shaft  1  is moved into an open position, not shown, the front ends of strips S 1 -S 12  coming out of the slitting shears are automatically directed onto contact surfaces  5 ,  9  assigned to guides F 10 -F 25  of second shaft  2 , which is positioned below first shaft  1 . Subsequently, shaft  1  is lowered so that the operating position illustrated in  FIG. 1  is reached. In this position, strips S 1 -S 12  are positioned in respective guides F 10 -F 25  assigned to them. 
   Shafts  1 ,  2  are then rotated in opposite directions. Accompanying this rotation, respective strips S 1 -S 12  are moved in the direction of shaft ends  1   b,    2   b  in correspondence with pitch s 10 -s 14  and/or s 20 -s 25  of respective guide F 10 -F 14  and/or F 20 -F 25 , starting from strip S 1  assigned to shaft center  1   a.  At the end of the rotational movement, they are at uniform intervals in their separated positions (FIG.  2 ). In this case, the interval actually reached between strips S 1 -S 12  in the separating position is dependent on the size of the rotational angle covered during the rotation of shafts  1 ,  2 . 
   As an alternative to introducing the strip front ends when upper shaft  1  is raised, the front ends of strips S 1 -S 12  may also be automatically pushed into guide gaps R 10 , R 20  between shafts  1 ,  2 . 
   Of course, it is also not absolutely necessary to drive shafts  1 ,  2  in opposite directions, as described in the example above. In an appropriate embodiment of guides F 10 -F 25 , shafts  1 ,  2  may also be driven in the same direction. 
   Clamping the strip front ends in guide gaps R 10 , R 20  during or after the separating procedure may be expedient if separating unit N supplies the strip front ends to further processing after the insertion and separating. 
   List of Reference Numbers 
   
       
         1 ,  2  shafts 
         1   a  shaft center 
         1   b,    2   b  shaft ends 
         3 ,  4  spacer 
         5  contact surface 
         6  edge 
         7  wall 
         8  collar 
         9  contact surface 
       D 1  diameter 
       D 2  diameter 
       E 1 , E 2  planes of conveyance 
       F 10 -F 14 , F 20 -F 25  guide 
       L lengthwise axis of the separating unit 
       N separating unit 
       P 10 -P 14 , P 20 -P 24  pairs 
       R 10 , R 20  conveyor gaps 
       S 1 -S 12  strips 
       s 10 -s 14 , s 20 -s 25  pitches 
       V 10 -V 110 , V 20 -V 210  isolating segments 
       W 1 , W 2  rotational axes of shafts  1 ,  2   
       X axial direction