Device for separating sheets piled up so as to form a stack, in a feeder of a sheet-processing machine

Information

  • Patent Grant
  • 6505826
  • Patent Number
    6,505,826
  • Date Filed
    Friday, February 16, 2001
    24 years ago
  • Date Issued
    Tuesday, January 14, 2003
    22 years ago
Abstract
A device for separating or singling sheets, which have been piled up to form a stack, in a feeder of a sheet-processing machine, having a transport element with a guide edge, includes a device for matching the shape of the guide edge to the contour of the topmost sheet at a front side of the stack, as viewed in a sheet transport direction.
Description




BACKGROUND OF THE INVENTION




Field of the Invention




The invention relates to a device for separating or singling sheets piled up so as to form a stack, in a feeder of a sheet-processing-machine, having a transport element with a guiding edge.




Heretofore known devices for separating or singling sheets, which have been piled up so as to form a stack, in a feeder of a sheet-processing machine have a transport element which is constructed as a pivotable flap and functions for transporting one or more sheets, by a pivoting movement, from the stack to a feeder roll of the machine. For this purpose, the respective sheet resting on the top of the stack is pushed along the guiding edge onto a guide face of the transport element which, by subsequent pivoting movement thereof, transports the respective sheet by the leading edge thereof to the feeder roll. Disadvantageously, the contour of the topmost sheet on the front side of the stack, as viewed in the sheet transport direction, is not always flat, so that it is possible for disruption to occur during the transport of the respective sheet from the stack to the feeder roll, for example, because the sheet is in a skewed position. Individual, visual averaging out of the different heights (lower edge region, higher center region) of the stack at the front side by an operator, and corresponding positioning of the stack and, in particular, of the sheet resting on the top thereof, in relation to the guide edge of the transport element does not lead to reliable results with regard to secure and reliable sheet transport from the stack to the feeder roll.




In addition, the published German Patent Document DE 34 11 886 A1 discloses a device having a first and a second detector for establishing the respective height of the front and rear region of a sheet stack or pile.




SUMMARY OF THE INVENTION




It is accordingly an object of the invention to provide a device of the type mentioned at the introduction hereto which, in a reliable, exact and repeatable manner, ensures correct separation or singling of sheets piled up to form a stack, in the feeder, and trouble-free transport of the respective sheets from the stack to a feeding roller of a sheet-processing machine.




With the foregoing and other objects in view, there is provided, in accordance with the invention, a device for separating or singling sheets, which have been piled up to form a stack, in a feeder of a sheet-processing machine, having a transport element with a guide edge, comprising a device for matching the shape of the guide edge to the contour of the topmost sheet at a front side of the stack, as viewed in a sheet transport direction.




In accordance with another feature of the invention, the shape-matching device has a transport element which is at least one of elastically and plastically deformable so as to match the shape of the guide edge to the contour of the topmost sheet.




In accordance with a further feature of the invention, the separating device includes a measuring device for determining the contour of the topmost sheet at the front side of the stack.




In accordance with an added feature of the invention, the separating device includes an adjusting device for matching the contour of the guide edge to the contour of the topmost sheet.




In accordance with an additional feature of the invention, the separating device includes a control unit operatively connected to the measuring device and to an adjusting device for matching the contour of the guide edge to the contour of the topmost sheet.




In accordance with yet another feature of the invention, the transport element is formed as an L profile in cross section and, at an end thereof, has a stop crosspiece which is bringable into engagement with the front side of the stack and, at a top thereof, the stop crosspiece has a guide crosspiece formed with a guide face onto which the topmost to sheet is transportable, the guide edge being located at the outside between the stop crosspiece and the guide crosspiece.




In accordance with yet a further feature of the invention, the transport element is formed rigid in the sheet transport direction and, at the stop crosspiece, is provided with a plurality of mutually spaced teeth for assisting in an elastic deformation of the transport element for matching the contour of the guide edge to the contour of the topmost sheet.




In accordance with yet an added feature of the invention, the separating device includes a fixing device for firmly clamping the teeth separately in order to stabilize the contour-matched guide edge.




In accordance with yet an additional feature of the invention, the fixing device is formed with holding openings wherein the teeth are freely positionable and firmly clampable, by deforming the transport element, so as to match the contour of the guide edge to the contour of the topmost sheet.




In accordance with still another feature of the invention, the adjusting device includes a plurality of actuators arranged spaced apart from one another.




In accordance with still a further feature of the invention, the actuators are formed as plungers having a position which is adjustable on a rotatable cam disc.




In accordance with an alternative feature of the invention, the actuators are formed as spindles operatable by a drive.




In accordance with still an added feature of the invention, the transport element is pivotable, between a stop position and a transfer position, about an axis of rotation extending perpendicularly to the sheet transport direction.




In accordance with still an additional feature of the invention, a matching of the contour of the guide edge to the contour of the topmost sheet by the adjusting device is dependent upon a pivoting-angle position thereof relative to the transport element.




In accordance with another feature of the invention, the guide edge is formed so as to be contour-matched to the topmost sheet in the stop position of the transport element and to be straight in the transfer position of the transport element.




In accordance with a further feature of the invention, the transport element is movable selectively counter to and in a respective contour-matching direction by a restoring spring element, respectively, compressible and expandable by the pivoting of the transport element.




In accordance with an added feature of the invention, in the transfer position of the transport element, the restoring spring element is compressed, the transport element is retracted and the contour matching of the guide edge is canceled, while, in the stop position of the transport element, the restoring spring element is expanded, the transport element is extended and the contour of the guide edge is completely matched to the contour of the topmost sheet.




In accordance with a concomitant feature of the invention, the transport element is formed as a continuous, pivotable flap, and the fixing device is formed as a pivoting shaft for the flap.




In order to achieve the objective of the invention, a separating device is proposed having features distinguished by the fact that the shape of the guide edge can be adapted or matched to the contour of the topmost sheet at a front side of the stack, as viewed in the sheet transport direction. This advantageously prevents the leading edge of the topmost sheet, which is generally not straight, but rather, bent downwardly, in particular in the edge regions thereof, from colliding with the guide edge as it is displaced from the stack onto a guide face of the transport element, and becoming skewed in an uncontrolled manner with respect to the sheet transport direction. By adapting or matching the contour of the guide edge to the leading edge of the topmost sheet, correct transport of the respective sheet from the stack to the feeder roll of a sheet-processing machine by the transport element is therefore reliably assured.




It is advantageous, for adapting or matching the contour of the guide edge, that the transport element be elastically and/or plastically deformable. A deformable guide edge is particularly suitable for exact and repeatable adaptation or matching of the contour to the leading edge of the topmost sheet. In this regard, both an elastic, plastic, as well as also a combined, partially elastic and partially plastic deformation of the guide edge is used to adapt or match the contour.




The separating device advantageously has a measuring device for determining the contour of the topmost sheet at the front side of the stack. By using a measuring device, for example, a sensor which can be displaced over the front side of the stack in the direction of the stack width, or a plurality of sensors arranged spaced apart over the front side of the stack in the direction of the width of the stack, it is possible, in a rapid, exact and possibly also continuous manner, to determine the contour of the respectively topmost sheet at the front side of the stack. Based upon these exact determined data, a precise, possibly automatic, adaptation or matching of the contour of the guide edge to the contour of the respective topmost sheet is assured.




The separating device preferably has an adjusting device for adapting or matching the contour of the guide edge to the contour of the topmost sheet. The use of an adjusting device makes it possible, preferably in an automatic manner, to implement exact and repeatable adaptation or matching of the contour of the guide edge to the contour of the topmost sheet. In addition, an adjusting device permanently operatively connected to the transport element permits continuous adaptation or matching of the contour of the guide edge to the contour of the topmost sheet, even during the operation of the separating device, using measured values which are likewise determined continuously.




According to a preferred embodiment, the separating device has a control unit which is operatively connected to the measuring device and the adjusting device. A control unit of this type permits automatic, user-friendly and reliable adaptation or matching of the contour of the guide edge, even during the operation of the separating device, with regard to the contour established, respectively, by the topmost sheet at the front side of the stack. Thereby, in a particularly effective manner, rapid and simultaneously correct transport of the respectively topmost sheet from the stack to the feeder roll of the sheet-processing machine by the transport element is assured.




The transport element is preferably formed as an L profile in cross section and, at an end thereof, has a stop crosspiece which is bringable into engagement or touching contact with the front side of the stack and, at the top thereof, the transfer element has a guide crosspiece onto a guide face of which the topmost sheet can be transported, the guide edge being located at the outside between the stop crosspiece and the guide crosspiece. A transport element constructed in this manner is particularly suitable for forming, on the one hand, a stop for the leading edges of a plurality of sheets resting on the stack at the top or stop crosspiece and, on the other hand, for being used as a transport element for transporting the respectively topmost sheet from the stack to the feeder roll. This transport element is suitable, in particular, for adapting or matching the contour of the guide edge or of the entire guide face by appropriate elastic and/or plastic deformation.




The transport element is advantageously formed rigid in the sheet transport direction and, at the stop crosspiece, is provided with a plurality of mutually spaced teeth assisting in the elastic deformation of the transport element to adapt or match the contour of the guide edge. The transport element, which is formed rigid in the sheet transport direction, is particularly suitable as a stop for the leading edges of the sheets resting on the top of the stack. A stop crosspiece provided with a plurality of mutually spaced teeth permits an exact and precisely repeatable elastic deformation of the guide edge or of the guide face of the guide crosspiece in order to achieve correct adaptation or matching of the contour.




According to an alternative embodiment, the teeth are firmly clampable separately by a fixing device in order to stabilize the contour-matched guide edge. The teeth of the stop crosspiece, which are firmly clampable relatively easily in a corresponding fixing device, are particularly suitable for fixing the adaptation or matching of the contour produced by elastic deformation of the transport element.




The fixing device is preferably provided with holding openings, wherein the teeth are freely positionable and firmly clampable, by deforming the transport element, in order to adapt or match the contour of the guide edge. Through the intermediary of a fixing device constructed in this manner and provided with holding openings, the adaptation or matching of the contour of the guide edge and of the guide face of the guide crosspiece, respectively, is possible in a user-friendly and precise manner. In this case, the elastic and/or plastic deformation of the transport element can be performed by manual setting or else automatically by a suitable adjusting device.




The adjusting device is advantageously formed as a plurality of actuators arranged spaced apart from one another. With a plurality of mutually spaced actuators operatively connected to the guide crosspiece of the transport element, it is possible for individual segments of the guide crosspiece (edge regions, central region) to be deformed elastically and/or plastically in such a way that exact and possibly also continuously adjustable contour-adaptation or matching of the guide edge and of the guide face, respectively, of the guide crosspiece is attainable.




According to an alternative embodiment, the actuators are formed as plungers having a position which is adjustable on a rotatable cam disc. Actuators constructed in this manner are particularly suitable for automatic and possibly continuous adaptation or matching of the contour of the guide edge by an appropriate adjustment of the position of the plungers operatively connected to the transport element.




According to a further, alternative embodiment, the actuators are constructed as spindles operatable by a drive. Spindles which are operated by a drive and are operatively connected to the transport element are also suitable, in particular, for automatic and possibly continuous adaptation or matching of the contour of the guide edge.




The transport element is advantageously pivotable, between a stop position and a transfer position, about an axis of rotation which is perpendicular to the sheet transport direction. A transport element that is movable in this manner is particularly suitable as a stop with respect to the leading edges of the sheets resting on the top of the stack and, simultaneously, as a transport element for rapid and correct transport of the respectively topmost sheet from the stack to the feeder roller of the sheet-processing machine.




The adaptation or matching of the contour of the guide edge by the adjusting device advantageously depends upon the pivoting-angle position with respect to the transport element. Because the contour-adapted or matched guide edge is used in particular to ensure reliable and correct displacement of the topmost sheet from the stack onto the transport element (guide face), the adaptation or matching of the contour of the guide edge does not necessarily have to be maintained until the corresponding sheet is transferred to the feeder roller. It may therefore be advantageous to change the contour of the guide edge depending upon the respective pivoting angle of the transport element.




The guide edge is preferably constructed so as to be contour-adapted or matched in the stop position of the transport element and to be straight in the transfer position of the transport element. Because the feeder roll of the sheet-processing machine is normally constructed straight in the direction of the sheet width, it is advantageous that the guide edge is correspondingly configured straight in the transfer position of the transport element, in order to permit correct and disruption-free transfer of the respective sheet to the feeder roll.




The transport element is preferably movable counter to or in the respective contour-adaptation or matching direction by a restoring spring element that is compressed or expanded by the pivoting of the transport element. Arranging one or more restoring spring elements which are operatively connected to the transport element ensures, in a relatively simple and particularly reliable manner, that the adapted or matching contour of the guide edge is canceled in the transfer position of the transport element by a pivoting angle-dependent movement or displacement of the transport element counter to the respective contour-adaptation or matching direction, because the respectively deformed segments of the transport element are reshaped, due to the displacement of the latter counter to the respective contour-adaptation or matching direction, when the adjusting device is not displaced correspondingly, forming a desired, straight contour of the guide edge.




In the transfer position of the transport element, the restoring spring element is advantageously compressed, the transport element is retracted and the contour adaptation or matching of the guide edge is canceled, while, in the stop position of the transport element, the restoring spring element is expanded, the transport element is extended and the contour of the guide edge is completely adapted or matched. A restoring spring element acting in this manner permits reliable and quick separation of the sheets, piled up to form a stack, in the feeder, and appropriate transport of the respectively topmost sheet from the stack to the feeder roll by the transport element.




The transport element is preferably formed as a continuous, pivotable flap, and the fixing device is constructed as a pivoting shaft for the flap. A transport element not formed from individual, separate segments but as a continuous flap can be mounted and adjusted in a relatively simple manner. In this case, a pivoting shaft formed as a fixing device helps to provide a particularly compact construction of the separating device.




Further advantageous refinements of the invention emerge from the description.




Other features which are considered as characteristic for the invention are set forth in the appended claims.




Although the invention is illustrated and described herein as embodied in a device for separating or singling sheets piled up to form a stack, in a feeder of a sheet-processing machine, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.




The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, wherein:











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a diagrammatic side elevational view of a feeder of a sheet-processing machine;





FIG. 2

is a diagrammatic front elevational view of a sheet stack formed of piled-up sheets, and of a transport element arranged at the front side of the stack;





FIG. 3

is a diagrammatic front elevational view of a transport element and a pivoting shaft belonging thereto;





FIG. 4

is a diagrammatic side elevational view of

FIG. 3

;





FIG. 5

is an enlarged diagrammatic view of

FIG. 4

, together with a first embodiment of an adjusting device operatively connected to the transport element;





FIG. 6

is a diagrammatic and schematic view like that of

FIG. 5

of a second embodiment of the adjusting device operatively connected to the transport element;





FIG. 7

is a diagrammatic side elevational view of a transport element which is pivotable in the direction of a feeder roll;





FIG. 8

is a diagrammatic side elevational view of a further embodiment of a transport element disposed in a stop position; and





FIG. 9

is another diagrammatic side elevational view of the transport element according to

FIG. 8

in a transfer position.











BRIEF DESCRIPTION OF THE DRAWINGS




Referring now to the drawings and, first, particularly to

FIG. 1

thereof, there is shown therein a diagrammatic side elevational view of a feeder


10


of an otherwise non-illustrated sheet-processing machine. Arranged in the feeder


10


is a stack or pile pallet


13


, whereon sheets


12


are piled up to form a stack or pile


11


. The stack pallet or pile


13


is displaceable in a vertical direction, i.e., upwardly and downwardly, together with the pile or stack


11


, as indicated by a double-headed arrow


14


in FIG.


1


. The feeder


10


has a device, generally identified by the reference numeral


50


, for separating or singling the sheets


12


piled up to form the stack or pile


11


. The respectively topmost sheet


12


is fed to the sheet-processing machine from the pile or stack


11


by the separating or singling device


50


in a transport direction represented by the arrow


15


.





FIG. 2

is a diagrammatic front elevational view of the stack or pile


11


arranged on the stack or pile pallet


13


, and a transport element


16


arranged opposite a front side


18


of the stack or pile


11


, as viewed in the sheet transport direction


15


(note FIG.


1


). The topmost sheet


12


on the stack or pile


11


is not straight, but is curved downwardly in the edge regions thereof, at the front side


18


, as viewed in the direction of the sheet width. The transport element


16


is formed with a guide edge


17


having a shape that is adapted to or matches the contour of the topmost sheet


12


at the front side


18


of the stack or pile


11


.





FIGS. 3 and 4

show the transport element


16


provided with a cross section preferably formed as an L profile and, at an end, provided with a stop crosspiece


22


and, at the top, provided with a guide crosspiece


23


. Between the stop crosspiece


22


and the guide crosspiece


23


, the guide edge


17


is located on the outside of the L-shaped transport element


16


. The transport element


16


is formed rigid in the sheet transport direction


15


, extending perpendicularly into the plane of the drawing of FIG.


3


. In order to ensure that the transport element


16


is preferably elastically deformable so as to adapt or match the guide edge


17


to the contour of the topmost sheet


12


at the front side


18


of the stack or pile


11


, the stop crosspiece


22


of the transport element


16


is formed with a plurality of mutually spaced teeth


24


. In order to stabilize the contour-adapted guide edge


16


, the teeth


24


can be firmly clamped separately from one another by a fixing device


25


. To this end, the fixing device


25


is provided with take-up or holding openings


26


, preferably formed as through-openings, wherein the teeth


24


can be freely positioned and firmly clamped by deforming the transport element


16


in order to match the contour of the guide edge


17


. The matching of the contour of the guide edge


17


can be effected by applying to the transport element


16


a deformation force according to the arrows


38


,


39


, in order, with reference to the contour of the topmost sheet


12


illustrated in

FIG. 2

(hanging corners) at the front side


18


of the stack or pile


11


, to obtain a contour which is curved downwardly in the end regions of the guide edge


17


. In this regard, the matching or adaptation of the contour of the guide edge


17


can be achieved by manually adjustable, elastic deformation or else automatically by an adjusting device not illustrated in FIG.


3


. Because the transport element


16


is preferably formed as a continuous, pivotable flap, the fixing device


25


is advantageously configured as a pivoting shaft


36


that is rotatable about an axis of rotation


32


. According to the embodiment of

FIG. 3

, it is thus possible for the transport element


16


both to be fixed in the pivoting shaft


36


, after producing an elastic matching or adaptation of the contour of the guide edge


17


, and to be pivoted into various operating positions by the very same pivoting shaft


36


.





FIG. 5

illustrates an alternative embodiment of an adjusting device


19


provided for adapting or matching the contour of the guide edge


17


and formed as an actuator. According to this embodiment, the adjusting device


19


is a spindle


30


which is operatable or adjustable by a drive


29


in the vertical direction of the pile or stack according to the double-headed arrow


31


. The spindle


30


is operatively connected to the guide crosspiece


23


of the transport element


16


so that, in the event of a movement of the spindle


30


in accordance with the double-headed arrow


31


, corresponding elastic and/or plastic deformation of the guide crosspiece


23


and, therefore, also of the guide edge


17


, is obtained in order to adapt or match the contour of the latter. The spindle


30


extends through a suitable passage opening


47


formed in the pivoting shaft


36


. The holding openings


26


formed as through-openings in the pivoting shaft


36


, permit unimpeded movement of the teeth


24


(note also

FIG. 3

) of the stop crosspiece


22


, according to the double-headed arrow


31


. The stop crosspiece


22


forms a stop in relation to the leading edges of the sheets


12


, piled up to form a stack


11


, at the front side


18


. The respectively topmost sheet


12


is thereby displaceable in the transport direction represented by the arrow


15


by non-illustrated elements belonging to the separating or singling device


50


onto a guide face


48


containing the guide edge


17


, in order to permit the separation of the sheets


12


and onward transport to the sheet-processing machine.





FIG. 6

shows a further alternative embodiment of the adjusting device


19


, which is constructed as an actuator in the form of a plunger


28


, the position of which is adjustable by a rotatable cam disc


27


. The plunger


28


according to

FIG. 6

functions in the same manner as the spindle


30


according to FIG.


5


. As

FIG. 6

illustrates, a measuring device


20


in the form of a sensor or detector, for example, is arranged above the front side


18


of the stack


11


, in order to determine the respective contour of the topmost sheet


12


in the direction of the sheet width, i.e., in the direction extending perpendicularly into the plane of the drawing of FIG.


6


. One possible contour of the topmost sheet


12


in the direction of the sheet width is illustrated in FIG.


2


. The determined measured values are transmitted by the measuring device


20


, via a transmission line illustrated symbolically as an arrow-headed line


44


, to a control unit


21


which, via a control line illustrated symbolically as an arrow-headed line


45


, initiates a corresponding adjustment of the plunger


28


in order to achieve suitable contour adaptation or matching of the guide edge


17


. Of course, the embodiment according to

FIG. 5

can also be provided with such a measuring device or sensor


20


and control unit


21


. In both embodiments according to

FIGS. 5 and 6

, a plurality of adjusting devices


19


spaced apart from one another in the direction of the sheet width are provided, in order to permit exact adaptation or matching of the contour of the guide edge


17


to the determined contour of the topmost sheet


12


at the front side


18


of the stack or pile


11


.




As

FIG. 7

illustrates, the transport element


16


is pivoted in the direction of a diagrammatically illustrated feeder roll


37


in accordance with the double-headed arrow


43


about the axis of rotation


32


by the pivoting shaft


36


in order to transfer a respective non-illustrated sheet


12


to the feeder roll


37


, and pivoted back again to the non-illustrated stack or pile


11


in order to pick up the topmost sheet


12


. The feeder roll


37


is rotatable about the axis of rotation


41


, according to the arrow


42


, in order to transport the respective sheet


12


to the sheet-processing machine. The construction and the functioning of the feeder roll


37


are already known and are therefore neither described nor illustrated in detail herein.





FIGS. 8 and 9

show the transport element


16


, which is pivotable in accordance with the double-headed arrow


43


, into a stop position (

FIG. 8

) and into a transfer position (FIG.


9


). In this preferred embodiment according to

FIGS. 8 and 9

, the adaptation or matching of the contour of the guide edge


17


depends upon the pivoting-angle position or setting of the transport element


16


. Provided for this purpose is a restoring spring element


34


which, assuming appropriate pivoting of the transport element


16


, is compressed or expanded due to a corresponding movement of the transport element


16


counter to and in the respective contour-matching direction, respectively. This movement of the transport element


16


is achieved by a cable pull mechanism


35


which cannot be lengthened but is flexible and firmly connected to the transport element


16


and which, at the other end thereof, is fixed to a stationary holder and, during an appropriate rotational movement according to the double-headed arrow


33


of the pivoting shaft


36


about the axis of rotation


32


, effects a retraction of the transport element


16


(note

FIG. 9

) and, respectively, an extension of the same transport element


16


(note FIG.


8


). In the transfer position of the transport element


16


(FIG.


9


), the restoring spring element


34


is compressed, the transport element


16


is retracted and the contour adaptation or matching of the guide edge


17


is canceled. In the stop position of the transport element


16


(note FIG.


8


), the restoring spring element


34


is expanded, the transport element


16


is extended and the contour of the guide edge


17


is completely matched or adapted. In the transfer position of the transport element


16


, the guide edge


17


is therefore formed straight, corresponding to the feeder roll


37


, in the direction of the sheet width.




Therefore, in the stop position of

FIG. 8

, the transport element


16


with the contour-matched or adapted guide edge


17


thereof is particularly suitable for ensuring reliable and disruption-free displacement of the topmost sheet


12


from the stack or pile


11


onto the guide face


48


of the guide crosspiece


23


. By pivoting the pivoting shaft


36


, which is fixedly connected to the transport element


16


against mutual rotation, about the axis of rotation


32


, the transport element


16


, together with the non-illustrated sheet


12


at least partially resting on the guide face


48


, assumes the transfer position thereof (note FIG.


9


), wherein the guide edge


17


is straight and therefore no longer contour-matched, and ensures the reliable and correct transfer of the respective sheet


12


to the feeder roll


37


.




In principle, it is possible, before beginning the separation and the transport of the sheets


12


, to adapt or match the shape of the guide edge


17


to the contour of the topmost sheet


12


at the front side


18


of the stack or pile


11


, and to keep this contour constant during the operation of the separating or singling device


50


. However, the preset contour of the guide edge


17


can also be adapted or matched, during the course of the processing of the stack or pile


11


, to the changing contour of the respectively-topmost sheet


12


at the front side


18


of the stack or pile


11


. There is therefore a continuous adaptation or matching of the contour of the guide edge


17


during the operation of the separating or singling device


50


.



Claims
  • 1. A device for separating or singling sheets, which have been piled up to form a stack, in a feeder of a sheet-processing machine, having a transport element with a guide edge, comprising a device for matching the shape of the guide edge to the contour of the topmost sheet at a front side of the stack, as viewed in a sheet transport direction.
  • 2. The separating device according to claim 1, wherein said shape-matching device has a transport element which is at least one of elastically and plastically deformable so as to match the shape of the guide edge to the contour of the topmost sheet.
  • 3. The separating device according to claim 1, including a measuring device for determining the contour of the topmost sheet at the front side of the stack.
  • 4. The separating device according to claim 1, including an adjusting device for matching the contour of the guide edge to the contour of the topmost sheet.
  • 5. The separating device according to claim 3, including a control unit operatively connected to said measuring device and to an adjusting device for matching the contour of the guide edge to the contour of the topmost sheet.
  • 6. The separating device according to claim 1, wherein said transport element is formed as an L profile in cross section and, at an end thereof, has a stop crosspiece which is bringable into engagement with the front side of the stack and, at a top thereof, said stop crosspiece has a guide crosspiece formed with a guide face onto which the topmost sheet is transportable, the guide edge being located at the outside between said stop crosspiece and said guide crosspiece.
  • 7. The separating device according to claim 6, wherein said transport element is formed rigid in the sheet transport direction and, at said stop crosspiece, is provided with a plurality of mutually spaced teeth for assisting in an elastic deformation of said transport element for matching the contour of the guide edge to the contour of the topmost sheet.
  • 8. The separating device according to claim 7, including a fixing device for firmly clamping said teeth separately in order to stabilize the contour-matched guide edge.
  • 9. The separating device according to claim 8, wherein said fixing device is formed with holding openings wherein said teeth are freely positionable and firmly clampable, by deforming said transport element, so as to match the contour of the guide edge to the contour of the topmost sheet.
  • 10. The separating device according to claim 5, wherein said adjusting device includes a plurality of actuators arranged spaced apart from one another.
  • 11. The separating device according to claim 10, wherein said actuators are formed as plungers having a position which is adjustable on a rotatable cam disc.
  • 12. The separating device according to claim 10, wherein said actuators are formed as spindles operatable by a drive.
  • 13. The separating device according to claim 1, wherein said transport element is pivotable, between a stop position and a transfer position, about an axis of rotation extending perpendicularly to said sheet transport direction.
  • 14. The separating device according to claim 5, wherein a matching of the contour of the guide edge to the contour of the topmost sheet by said adjusting device is dependent upon a pivoting-angle position thereof relative to said transport element.
  • 15. The separating device according to claim 13, wherein the guide edge is formed so as to be contour-matched to the topmost sheet in said stop position of said transport element and to be straight in said transfer position of said transport element.
  • 16. The separating device according to claim 13, wherein said transport element is movable selectively counter to and in a respective contour-matching direction by a restoring spring element, respectively, compressible and expandable by said pivoting of said transport element.
  • 17. The separating device according to claim 16, wherein, in said transfer position of said transport element, said restoring spring element is compressed, said transport element is retracted and the contour matching of the guide edge is canceled, while, in said stop position of said transport element, said restoring spring element is expanded, said transport element is extended and the contour of the guide edge is completely matched to the contour of the topmost sheet.
  • 18. The device according to claim 1, wherein said transport element is formed as a continuous, pivotable flap, and said fixing device is formed as a pivoting shaft for said flap.
Priority Claims (1)
Number Date Country Kind
100 07 029 Feb 2000 DE
US Referenced Citations (5)
Number Name Date Kind
3991998 Banz et al. Nov 1976 A
6273416 Watanabe et al. Aug 2001 B1
6378858 Suga Apr 2002 B1
6382621 Inoue et al. May 2002 B1
6402135 Werner Jun 2002 B1
Foreign Referenced Citations (2)
Number Date Country
34 11 886 Oct 1984 DE
195 09 487 Jun 1996 DE