Abstract:
In processing web material, the material is passed through a guiding arrangement which has a plurality of guide elements. In order to enable removing the guide element for repair without disturbing the web material, each of the guide elements is provided with a lifting arrangement which is concentric to the guide element and is movable from one angular position withdrawn from the path of the elongated material engaging the guide element to a second position lifting the elongated material off of the guide element so that the guide element can be axially withdrawn from the machine.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    The present invention is directed to an apparatus for guidance of an elongated material, particularly of a web-like material, and of a traction mechanism in the web-processing machine. The invention is also directed to a system for printing or copying and to a method for the guidance of an elongated material.  
           [0002]    Examples of web-processing machines are printers or copies wherein web-shaped recording media are guided via guide elements, for example drums or rolls. In order to thread web material through the machine at the beginning of a processing event, traction mechanisms in the form of traction cables or bands are often employed. These cables or bands grasp a leading section of the web material and guide it largely automatically through the machine. The traction mechanisms are also conducted via guide elements. Examples of these printers and copiers are disclosed by WO 98/39691, whose disclosure is incorporated herein by reference thereto.  
           [0003]    In known printers and copiers, the guide elements for the web material or the traction mechanisms as well as their bearings are generally parts that must be maintained or replaced at specific time intervals. A relatively high assembly outlay is required for replacing these component parts. In addition, the web material and/or traction mechanism must usually be removed.  
         SUMMARY OF THE INVENTION  
         [0004]    An object of the present invention is to offer an apparatus and a method that allows assembly work at the guide elements for the elongated material to be implemented in a simple way.  
           [0005]    This object is achieved by an apparatus for guidance of an elongated material in which a pivotable or shiftable lifting mechanism or element is provided for each guide element for guiding the elongated material, said lifting element being pivotable from a first position at the guide element outside of the region wherein the elongated material runs via the guide elements into a second position where it holds the elongated material at a distance from the guide elements.  
           [0006]    According to the invention, the pivotable lifting mechanism is allocated to each guide element for guiding the elongated material, for example a material web or a traction mechanism. This lifting mechanism has two positions. In the first position, the lifting mechanism is outside of the region wherein the elongated material runs via the guide element and is, thus, in a retracted position. In the second position, the lifting mechanism holds the elongated material at a distance from the guide element. In this way, assembly work can be implemented at the guide element without having to remove the elongated material from the machine. This arrangement facilitates the assembly job.  
           [0007]    According to another aspect, a system for printing or copying is provided which is equipped with the apparatus of the present invention, and this system for printing or copying can be easily maintained and requires very little assembly outlay.  
           [0008]    Other advantages and features of the invention will be readily apparent from the following description of the preferred embodiments, the drawings and claims. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]    [0009]FIG. 1 is a schematic illustration illustrating the principles of the present invention;  
         [0010]    [0010]FIG. 2 is a perspective end view of an exemplary embodiment having a deflection roller and a lifting mechanism in a locked or retracted position;  
         [0011]    [0011]FIG. 3 is a perspective illustration of the device of FIG. 2 with the lifting mechanism in the axially unlocked position;  
         [0012]    [0012]FIG. 4 is an exploded perspective view of an insert with the deflection roller being removed from the rotary flange;  
         [0013]    [0013]FIG. 5 is a perspective view of the embodiment of FIGS.  2 - 4  being installed in a machine frame which has a portion cut away for purposes of illustration;  
         [0014]    [0014]FIG. 6 is a perspective view of a second exemplary embodiment of a guide drum with two deflection rollers;  
         [0015]    [0015]FIG. 7 is a perspective view of portions of a machine frame for receiving the guide drum and two deflection rollers of FIG. 6;  
         [0016]    [0016]FIG. 8 is a perspective view of the guide drum of FIG. 6 with portions disassembled;  
         [0017]    [0017]FIG. 9 is a perspective view of a lifting element in a first, retracted position;  
         [0018]    [0018]FIG. 10 is a perspective view of the lifting element of FIG. 9 in the second, actuated position;  
         [0019]    [0019]FIG. 11 is a perspective view illustrating the support of the material web and cables by the lifting element of FIGS. 9 and 10 in the second, actuated position; and  
         [0020]    [0020]FIG. 12 is a perspective view of the lifting element of FIGS. 9 and 10 in the first, retracted position. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0021]    The principles of the present invention are schematically shown in FIG. 1, wherein a traction mechanism in the form of a traction cable  10  is conducted around a plurality of deflection rollers  12 ,  14  and  16  that are generally referred to as guide elements. In the example of this Figure, a respective deflection of the traction cable  10  by 90° occurs at each of the rollers  12 ,  14  and  16 . Each deflection roller has a lifting mechanism  18 ,  20  and  22 . By pivoting the lifting mechanisms  18 ,  20  and  22  through 180° concentric to the central axis of the respective deflection rollers  12 ,  14  and  16 , the traction cable  10  can be lifted off of the respective deflection roller  12 ,  14  and  16  or lowered thereon.  
         [0022]    As illustrated, the lifting mechanisms  18  and  20  are shown in the respective first or retracted position, wherein the traction cable  10  proceeds unimpeded over the respective guide rollers  12  and  14 . However, the lifting element  22 , as shown in solid lines, is in the second or actuating position, wherein it holds the traction cable  10  at a distance from the deflection roller  16 . In this condition, the deflection roller  16  can be removed from the machine or replaced without having to remove the traction cable  10 . On the contrary, this traction cable  10  remains in a guided and potentially tensed condition as a result of being lifted off of the roller  16  by the lifting mechanism  22 . The first or retracted position of the lifting mechanism  22  for the roller  16  is shown by broken lines. It is, thus, pivoted by 180° in the direction of the arrow P 1  relative to the second position. This first position is the normal operating position, wherein the traction cable  10  lies on the deflection roller  16 . The second position, wherein the traction cable  10  is lifted off from the deflection roller  16 , is then reached by pivoting by 180° in the direction of the arrow P 1 .  
         [0023]    Details of the assembly composed of the deflection roller  16  and the lifting mechanism  22  are shown in FIGS.  2 - 5 . In FIG. 2, the lifting mechanism is illustrated in the first or retracted position. In FIG. 3, the lifting mechanism is in the second or actuated position. FIG.  4  shows an exploded view of the various parts of the assembly with the deflection roller  16  and the lifting mechanism, while FIG. 5 shows the assembly installed in a frame in a perspective illustration.  
         [0024]    According to FIG. 2, the deflection roller  16  has a guide or rail groove  24  that accepts the traction cable  10 . The deflection roller  16  is rotatably mounted on a shaft  26 , which is best illustrated in FIG. 4. An insert  28  that has a handle  30  with a grasping region is rigidly held on this shaft  26 . The insert  28  carries an interlocking flange  32  which has a semicircular shape that is best illustrated in FIGS. 3 and 4.  
         [0025]    As shown in FIG. 4, the insert  28  has an annular section  34  that is introducible into a rotary flange  36 . The rotary flange  36  has dog pins, such as  38 , that engage into dog holes  40  for a twist-resistance seating of the insert  28 . The rotary flange  36  carries an approximately semi-cylindrically-shaped lifting ring segment  42  whose inside diameter is slightly greater than the outside diameter of the deflection roller  16 . The lifting ring  42  has a rail or guide groove  44  for the acceptance of the traction cable  10 . Mounting elements  46  serve the purpose of dependable introduction of the cable and, thus, as assembly aids.  
         [0026]    [0026]FIGS. 2, 3,  4  and  5  also show the arrangement of an interlocking member plate or diaphragm  48  in the form of a semicircular ring. This interlocking diaphragm  48  is connected with screws  50  to a rigid frame  52  of a machine, which is shown in greater detail in FIG. 5.  
         [0027]    The function of the assembly comprising the deflection roller  16  and the lifting mechanism  22  is explained below with reference to FIGS.  2 - 5 . FIG. 4 shows the condition wherein the deflection roller  16  together with the insert  28  are not in engagement with the rotary flange  36 . In this condition, the deflection roller  16  or its bearing or the entire unit comprising the components  16  and  28  can be replaced. For inserting the insert  28  with the deflection roller  16 , the insert  28 , in the illustrated position, is guided in the direction of the dot-dashed lines so that the interlocking flange  32  can be introduced above the interlocking member  48  and the annular section  34  can be guided in an inner ring  54  of the rotary flange  36 , so that the dog pins  38  proceed into the dog holes  40 . In this way, the rotary flange  36  is torsionally connected to the insert  28 . The interlocking flange  32  lies against a surface  56  of the rotary flange  36 , so that the interlocking flange  32  can be pivoted or rotated into the free interspace behind the interlocking member or plate  48 .  
         [0028]    With the combination of the rotary flange  36  and the flange  32  being rotated to the first position, as shown in FIG. 2, the lifting mechanism  22  will be rotated into the first or retracted position. The traction cable  10  is accepted by the rail groove  24  of the deflection roller  16 . The interlocking flange  32 , as mentioned, is situated behind the interlocking member  48 , so that the insert  28  cannot be moved out in an axial direction. The interlocking flange  32  and the interlocking plate  48  function as an axial interlocking mechanism and are actually locked in the illustrated position.  
         [0029]    In order to proceed into the second position for the lifting mechanism  22  shown in FIG. 3, the handle  30  is turned in the direction of the arrow P 2  through 180°, which results in the insert  28  together with the rotary flange  36  being rotated or pivoted through 180°. After the implementation of this motion, it can be seen in FIG. 3 that a clearance  58  is present between the interlocking member  48  and the interlocking flange  32 , so that the insert  28  can be removed in the direction of the arrow P 3 . The axial interlocking mechanism, which is formed by the interlocking flange  32  and the interlocking plate  48 , is axially unlocked in this position, so that the insert  28  can be axially removed in the direction P 3 . As a result of the swivel motion or rotary motion in the direction of the arrow P 2 , the lifting ring  42  is likewise moved in the direction of the arrow P 2 , as a result whereof, its rail groove  44  accepts the traction cable  10 . Given this swivel motion, the mounting elements  46  serve as guide aids for the traction cable  10 . In the condition of the second position of the lifting mechanism  22 , which is shown in FIG. 3, the traction cable  10  is held at a distance from the deflection roller  16  so that the deflection roller  16  together with the insert  28  can be moved out in an axial direction P 3 .  
         [0030]    [0030]FIG. 5 illustrates the assembly comprising the deflection roller  16  and the lifting mechanism  22  in the first or retracted position. It can be seen that the annular section  58 ′ is received in a ring bearing  60  of the rigid frame  52  of the machine, which is shown in FIG. 5 with a portion cut away for purposes of illustration. In addition, an end face  62  as well as an annular surface  64  of the rotary flange  36  lie against bearing surfaces  66  and  68  formed by a recess in the frame  52 . It can be seen with reference to FIG. 5 that the deflection roller  16  is arranged in a region within the machine that is difficult to access. In contrast thereto, the insert  28  accepted in the rotary flange  36  is easily accessible proceeding from the left in FIG. 5, so that the insert  28  together with the deflection roller  16  can be removed in an axial direction when the lifting mechanism  22  is in the second position shown in FIG. 3.  
         [0031]    An inventive exemplary embodiment of the assembly, which comprises a guide drum  70  having deflection rollers  16  arranged at both sides or ends as typically occurs in a web-processing machine, for example in a printing machine, is illustrated in FIGS.  6 - 12 . Identical parts continue to be identically referenced. The guide drum  70  serves the purpose of guiding a web material. The deflection rollers  16  for guiding a traction mechanism, for example a traction cable, are provided on a shared hollow shaft  72  on both ends of the guide drum  70 . This traction mechanism serves the purpose of largely automatically pulling a leading section of the web material through the entire machine at the beginning of the web transport. The deflection roller  16  shown at the right in FIG. 6 is connected to the insert  28 , which was described in the preceding Figures, and is merely shown schematically in FIG. 6 and in the following Figures. As set forth later, the entire assembly having the two deflection rollers  16 , the guide drum  70  and the hollow shaft  72  can be removed by removing the insert  28 .  
         [0032]    The structure with frame-fixed components, i.e., components that are rigidly connected to the frame part  52 , are shown in FIG. 7. These components include a flange  74  that carries an acceptance mandrel  76 . This acceptance mandrel  76  has a conical surface  78  in the region of the flange  74  that serves the purpose of fine-centering once receiving the hollow shaft  72 , which is telescopically inserted over the mandrel  76 . The acceptance mandrel  76  serves as an assembly aid by telescopically receiving the hollow shaft  72  of FIG. 6 when it is pushed from the right side of the frame  52  over the acceptance mandrel in the direction of the arrow P 4 . The right-hand housing frame also carries an interlocking member  48 . The arrow P 5  indicates the swivel or rotational movement by which the insert  28  can be swivelled or rotated in order to proceed into the interlocked position wherein an axial locking between the interlocking flange  32  of the rotary flange  36  and the interlocking diaphragm or member  48  occurs.  
         [0033]    An exploded view of the structure of the assembly of FIG. 6 is shown in FIG. 8. To be seen are the left-hand deflection roller  16  for the traction cable  10 , the bearing elements  80  that hold the drum-shaped guide drum  70  and bear on the hollow shaft  72 , the bearing elements  82  for the right-hand bearing of the guide drum  70 , the right-hand deflection roller  16  for the corresponding traction cable  10 , the insert  28  and the bearing screws  84  which connect to the end section of the hollow shaft  72 .  
         [0034]    A lifting mechanism, generally indicated at  22  overall in FIGS.  6 - 12 , is shown in FIG. 9. The lifting mechanism  22  comprises a lifting element  86  that has the form of a semi-cylindrical cladding or jacket and is connected to the rotary flange  36  at the right-hand side of FIG. 9. The rotary flange  36  is constructed in the fashion of the rotary flange  36  of FIGS.  2 - 5 . A supporting element  88 , which is connected to the semi-cylindrically cladding-shaped lifting element  86  is seated on the flange  74  on the left-hand side of FIG. 9.  
         [0035]    As illustrated in FIG. 10, the arrangement of FIG. 9 is viewed onto the semi-cylindrically cladding-shaped lifting element in the second position. The lifting element  86  has acceptance elements  90  at the two ends for the acceptance of the traction cable  10  when the element is in the second position, wherein the lifting element  86  holds the traction cable  10  at an elevated position from the deflection rollers  16 .  
         [0036]    [0036]FIG. 11 shows the arrangement with the lifting element  86  during operation, namely in the second position, wherein the lifting element  86  holds both the traction cables  10  in the acceptance elements  90  at a distance from the deflection rollers  16  and also holds a material web  92  at a radial distance from the guide drum  70 . In this condition, the insert  28  can be removed from the rotary flange  36  so that all parts shown in FIG. 8 can be removed in an axial direction. For example, the guide drum  70  and the deflection rollers  16  and their bearings can be completely replaced in this manner. Neither the traction cable  10  nor the material web  92  needs to be removed during this replacement. The entire replacement can proceed from the right-hand side of the housing in FIG. 11. Separate access to the left-hand housing side in FIG. 11 is not required.  
         [0037]    [0037]FIG. 12 shows the operating condition in the first or retracted position for the lifting mechanism. The lifting element  86  is then pivoted or rotated into a position wherein the material web  92  is now engaged on the guide drum  70  and the traction cables  10  also run on the deflection rollers  16 . The lifting element  86  does not impede the rolling of the material web  92  on the roller or drum  70  or the traction cables  10  on the rollers  16 .  
         [0038]    The described exemplary embodiments can be modified within the framework of the invention. For example, the lifting element  86  can have a form deviating from a semi-cylindrical cladding form and can describe an angle greater than or less than 180° as seen in the circumferential direction. When only the traction mechanisms are to be lifted up, semi-annular lifting elements in the fashion of lifting elements  42  in FIGS.  2 - 5  can be employed in the environment of the deflection roller  16 . The lifting element removed from the rotary flange can then be moved with the assistance of a torque that is transmitted via the hollow shaft  72 . In order for them to be able to remove the shaft  72 , such a semi-annular lifting element should be mechanically connected to the hollow shaft  72  in a force-transmitting fashion via a releasable coupling, for example a claw coupling.  
         [0039]    The guide elements  16  for the cable in the illustrated exemplary embodiment are implemented as rollers and the guide element for the web is a drum  70 . However, it is also conceivable that these guide elements are torsionally arranged, and this is particularly true for guide elements for guiding web materials.  
         [0040]    Although various minor modifications may be suggested by those versed in the art, it should be understood that we wish to embody within the scope of the patent granted hereon all such modifications as reasonably and properly come within the scope of our contribution to the art.