Device for changing the position of objects conveyed in an overlapping stream

Information

  • Patent Grant
  • 6554125
  • Patent Number
    6,554,125
  • Date Filed
    Wednesday, August 23, 2000
    24 years ago
  • Date Issued
    Tuesday, April 29, 2003
    21 years ago
  • Inventors
  • Original Assignees
  • Examiners
    • Dayoan; D. Glenn
    • Carpenter; Scott
    Agents
    • Alston & Bird LLP
Abstract
An apparatus for changing the position of flexible flat objects, in particular printed products, as they are advanced on a first conveyor in an overlapping stream, and which includes a position changing device positioned above the first conveyor and which comprises a displacement member which is moved along a movement path by means of a drive. The movement path includes one section which extends rectilinearly and in the conveying direction and the displacement member is driven at a speed which corresponds at least approximately to the conveying speed of a second conveyor toward which the displacement member conveys the objects. The second conveyor delivers the objects to a discharge conveyor which is provided with transport clamps which are delivered individually to a fitting point where they receive an object from the second conveyor.
Description




BACKGROUND OF THE INVENTION




The present invention relates to an apparatus for changing the position of flexible, flat objects, in particular printed products, arriving on a first conveyor in an overlapping stream.




An apparatus of this type is disclosed by CH Patent Number 677 778. Arranged in the downstream end region of a first conveyor, between the conveyor tapes forming a conveying plane, is a position-changing device. It has two disks which are arranged beside each other in the conveying plane and driven in opposite directions, on each of which a displacement cam is situated eccentrically. These displacement cams are intended in each case to come into contact with the rear edge of each object arriving on the first conveyor in an overlapping stream, to accelerate said object in the conveying direction and to feed it to the second conveyor. The latter is assigned a braking device, which is intended to brake the objects accelerated by the rotation of the disks to the conveying speed of the second conveyor. The high speeds and retardations associated with this apparatus, in particular in the case of a high processing capacity, constitute a considerable stress on the objects, and can lead to damage. Furthermore, in order to achieve a specific desired spacing between the objects on the second conveyor, the distance of the displacement cams from the axes of rotation of the disks, and the rotational speed of the disks, depend on one another and also on the conveying speeds of the first and second conveyors, the desired spacing and the spacing of the objects in the arriving overlapping formation, for which reason rather closer limits are placed on the ability of the apparatus to be used.




In a further apparatus, which is disclosed in CH 631 410 and is connected between a first and a second conveyor, printed products are conveyed using displacement means which are fixed to a toothed chain and are provided with contact rollers, which are driven in the opposite direction to the direction of motion of the displacement means. The printed products are therefore not gripped immediately by the displacement means but only during the transfer between the first and the second conveyor. The duration of the synchronization procedure depends on the printed products, so that universal use of the apparatus is called into question.




The published specification WO 95/03989 discloses a further apparatus in which printed products are transferred from a first to a second conveyor. The second conveyor has a chain, on which transport clamps are firmly mounted at equal intervals from one another. The transport clamps are therefore filled periodically with a printed product at a transfer point. A position-changing device is provided to ensure that the printed products in each case arrive at the second conveyor at the correct time. The requirements on the first conveyor and the preceding conveying systems are therefore very high, so that if there are irregularities in the feed, disruptions can easily occur.




It is therefore an object of the present invention to develop the apparatus of known type in such a way that it can be used more universally, with more careful handling of the objects.




SUMMARY OF THE INVENTION




The above and other objects and advantages of the present invention are achieved by the provision of an apparatus for changing the position of the objects arriving on a first conveyor, for example, in an overlapping stream, and which comprises a position changing device arranged in the region of the first conveyor and which has a displacement means which is moved along a movement path. During at least one section of the movement path, the displacement means is driven by means of a drive at a higher speed than the conveying speed of the first conveyor and so as to feed each object delivered to the position changing device to a second conveyor, which is driven at a conveying speed that is higher than that of the first conveyor. The one section of the movement path extends at least approximately rectilinearly and in the conveying direction, and the drive drives the displacement means in the one section at a speed which is at least approximately equal to the conveying speed of the second conveyor.




The at least approximately rectilinear movement path of the displacement means permits the speed of the objects to be kept low; it never needs to be higher than the conveying speed of the second conveyor, which permits high processing capacities with careful handling of the object.











BRIEF DESCRIPTION OF THE DRAWINGS




The invention will now be explained in more detail with reference to exemplary embodiments illustrated in the drawing, in which, in purely schematic form:





FIG. 1

shows a side view of part of a device for feeding objects arriving in an overlapping stream to a discharge conveyor, the device for matching the overlapping stream to the requirements of the discharge conveyor having, inter alia, a first embodiment of an apparatus according to the invention;





FIG. 2

shows, likewise in side view, a device for feeding objects arriving in an overlapping stream to a discharge conveyor having a second embodiment of the apparatus according to the invention;





FIG. 3

shows a front view of a third embodiment of the apparatus according to the invention;





FIG. 4

shows, in a section along the line IV—IV in

FIG. 3

, the embodiment shown there of the apparatus according to the invention;





FIG. 5

shows a side view of a fourth embodiment of the apparatus according to the invention;





FIG. 6

shows a side view of a fifth embodiment of the apparatus according to the invention; and





FIG. 7

shows, in front view and partly sectioned, the apparatus shown in FIG.


6


.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




The apparatus


10


shown in

FIG. 1

has a first belt conveyor


12


which is driven in the conveying direction F at a first conveying speed v


1


. Connected immediately downstream of said first belt conveyor is a second belt conveyor


14


, which is driven in the conveying direction F at a second conveying speed v


2


which is higher than the first conveying speed v


1


.




Arranged above the first belt conveyor


12


is a position-changing device


16


. It has a displacement means


18


of hook-like design, which can be moved, by means of a drive


22


designed as a cylinder/piston unit


20


, in and counter to the conveying direction F, along a rectilinear movement path


24


. As indicated with dashed lines, the cylinder/piston unit


20


is connected to a control device


26


, which is influenced by the conveying speed v


2


of the second belt conveyor


14


.




Flexible, flat objects


28


, printed products in the present case, arrive on the first belt conveyor


12


in an overlapping formation S


1


, in which each object


28


rests on the respectively following object. The spacing between the rear edges


30


of successive objects


28


is designated by A


1


. It can be subject to considerable scatter. The position-changing device


16


is intended to act positively, with the displacement means


18


, on the rear edge


30


of each object


28


fed by the first belt conveyor


12


, and to feed it in the conveying direction F to the second belt conveyor


14


in such a way that the rear edges


30


of successive objects


28


are spaced apart from one another by a desired spacing A


2


in the overlapping formation S


2


. For this purpose, the drive


22


is operated at a frequency f which is given by the quotient of the second conveying speed v


2


and the desired spacing A


2


. During a displacement stroke in the conveying direction F, the displacement means


18


is accelerated, in a short acceleration section of the movement path


24


, to a speed v which corresponds to the second conveying speed v


2


, is then moved onward at this speed in a section


24


′ of the movement path and braked in a braking section, which is again short. The downstream end of the section


24


′ of the movement path is arranged at a distance from the second belt conveyor


14


such that the object


28


respectively fed by the position-changing device


16


is carried along by the second belt conveyor


14


when the displacement means runs into the braking section.




A discharge conveyor


32


is connected downstream of the second belt conveyor


14


, as indicated by dash dotted lines. It has transport clamps


34


which are arranged one behind another and are intended in each case to pick up an object


28


from the second belt conveyor


14


and convey it away. The second conveying speed v


2


, the desired spacing A


2


and the phase angle of the objects


28


on the second belt conveyor


14


—and thus the position-changing device


16


—are coordinated with the discharge conveyor


32


in such a way that each transport clamp


34


is fed one object


28


.




Arranged upstream of the position-changing device


16


, above the first belt conveyor


12


, is a counting device


36


. Arranged on a counting drive


38


is a counting element


40


, which is intended to be placed on the rear edge


30


of each object


28


, in order, for each object


28


, to emit a counting signal to a counter. A pressing roller


39


prevents objects


28


moved in the conveying direction by the counting element


40


being able to carry along the respectively following object by means of friction, if need be. Particularly preferred embodiments of the counting device


36


are disclosed in U.S. Pat. Nos. 6,363,133; 6,349,125; and 6,359,954. The disclosures of these patents are incorporated by reference in the present application.




Connected upstream of the first belt conveyor


12


is a feed conveyor


42


, likewise constructed as a belt conveyor. Arranged above the feed conveyor


42


is a device


44


for pulling apart the objects


28


arriving on the feed conveyor


42


in a closely packed, overlapping formation S


0


. It has a striking element


48


which is arranged on a striking drive


46


and is intended to be placed on the rear edge


30


of each object


28


fed in the overlapping formation S


0


and to feed said object to the first belt conveyor


12


at a speed which is higher than the conveying speed v


0


of the feed conveyor


42


. At the same time, a weighted roller


39


′ prevents the following object


28


being carried along by friction. The conveying speed v


0


of the feed conveyor


42


is lower than the conveying speed v


1


of the first belt conveyor


12


. In order to ensure that the objects


28


fed to the first and second belt conveyors


12


,


14


are carried along, weighted rollers


50


and


50


′ interact with these belt conveyors in the upstream starting area. A further preferred embodiment of the device


44


is disclosed in U.S. Pat. No. 6,363,133.




The apparatus shown in

FIG. 1

operates as follows. In the case of a position-changing device


16


which is synchronized with the discharge conveyor


32


, and a synchronized second belt conveyor


14


, a drive unit


52


for the first belt conveyor


12


is adjusted in such a way that each object


28


is caught individually by means of the displacement means


18


and fed to the second belt conveyor


14


in correct phase and with the required spacing A


2


. The feed conveyor


42


, the counting device


36


and the device


44


are coordinated with the speed of the drive unit


52


, which ensures that the objects


28


arriving in the overlapping formation So are at least pushed apart to the necessary spacing Al and are counted.




In the case of the apparatus


10


shown in

FIG. 2

, the displacement means


18


has two displacement elements


18


′ driven in antiphase. The control device


26


controls the drive


22


of the displacement elements


18


′ in such a way that, at the cycle rate of the second belt conveyor—this is given by the quotient of the desired spacing A


2


and the second conveying speed v


2


—in each case a displacement element


18


′ is located at the downstream end of the section


24


′ of the movement path. Each displacement element


18


′ is assigned a sensor element


54


which, when the relevant displacement element


18


′ interacts in each case with the rear edge


30


of an object


28


, emits a signal to a counter


56


and to a release device


58


of the discharge conveyor


32


connected downstream of the second belt conveyor


14


.




A feed conveyor


42


is again connected upstream of the first belt conveyor


12


, and its conveying speed v


0


corresponds to the conveying speed v


1


of the first belt conveyor


12


. The latter rests in an undershot manner on a coil


60


. The objects


28


wound onto a winding core


62


in a closely packed, overlapping formation S


0


are unwound from said coil


60


, together with a winding tape under tension. As viewed in the unwinding direction W, in the overlapping formation S


0


, each object rests on the respectively following object with a small spacing A


0


between the rear edges


30


.




The drive unit


52


for the first belt conveyor


12


, the feed conveyor


42


and the coil


60


is coordinated with the drive


22


of the position-changing device


16


in such a way that the displacement capacity of the position-changing device


16


is approximately 20% higher than the capacity with which the objects


28


are fed to the position-changing device


16


. Since the displacement elements


18


′ are driven at a higher frequency than the objects


28


arrive, not every displacement element


18


′ displaces an object


28


into the active region of the second belt conveyor


14


with every delivery stroke in the conveying direction F. As a result, gaps L appear in the overlapping stream S


2


as a result of missing objects


28


, but because of the synchronization between the second belt conveyor


14


and the position-changing device


16


, it is ensured that the spacing between the rear edges


30


of successive objects


28


always corresponds to the desired spacing A


2


or an integer multiple thereof.




For completeness, it should be mentioned that again a weighted roller


50


′ interacts with the second belt conveyor


14


, and a retaining device


64


equipped with an endless belt—carrying out the same function as the weighted rollers


39


and


39


′-interacts with the first belt conveyor


12


upstream of the position-changing device


16


, in order to prevent objects


28


being carried along by objects


28


moved by the displacement means


18


.




The discharge conveyor


32


has individually moveable transport clamps


34


which are arranged one behind another in a guide


66


. Directly before the pick-up point


68


at the downstream end of the second belt conveyor


14


, the guide


66


runs around a drive wheel


70


which, as indicated by dash-dotted lines, has a drive coupling to the second belt conveyor


14


. The drive wheel


70


has catching elements at regular intervals on the circumference for the transport clamps


34


. Positioned immediately upstream of the drive wheel


70


is the release device


58


. Since the release device


58


in each case releases a transport clamp


34


only upon a signal from the counter


56


, it is ensured that each transport clamp


34


is fed an object


28


. This is indicated by the fact that, corresponding to the gaps L in the overlapping formation S


2


, catching elements of the drive wheel


70


are not occupied by a transport clamp


34


. This extremely simple control merely makes it necessary that, between the release device


58


and the pick-up point


68


, an equal number or more transport clamps


34


—in this case the release device will be controlled in an appropriately delayed manner—will find space when there are objects


28


at the desired spacing A


2


between the position-changing device


16


and the pick-up point


68


. At or downstream of the pick-up point


68


, the transport clamps


34


occupied by an object are coupled, for example magnetically, to a drive element which is moved, at least in some sections, along the guide


66


, and conveyed away from the pick-up point


68


. A particularly suitable embodiment of the discharge conveyor


32


is disclosed in the earlier CH Patent Application Number 1997 2963/97 and the corresponding U.S. patent application Ser. No. 09/554,546.




Since gaps L are permissible in the device shown in

FIG. 2

, the requirements on the regulation of the drive unit


52


for the first belt conveyor


12


and the coil


60


are low. It is merely necessary to ensure that, in the case of a permissible minimum spacing A


0


in the closely packed, overlapping formation S


0


, a maximum permissible first conveying speed v


1


is not exceeded.




The possibility of the independent adjustment of the speed, the stroke and the frequency with which the displacement means are moved, permit great flexibility.




A particularly preferred embodiment of the position-changing device


16


, such as is advantageously used in the device shown in

FIG. 2

, is illustrated in

FIGS. 3 and 4

. It has two guide rails


72


which are arranged in parallel and extend in the conveying direction F. Guided in each guide rail


72


is a slide


74


, to which a self-sprung displacement element


18


′, for example produced from spring steel, is fastened at one end. The displacement element


18


′, which projects beyond the relevant slide


74


in the conveying direction F, is constructed in its free, leading end region as an insertion tongue


76


, which is provided with a reflector element


78


on its side facing away from the first belt conveyor


12


. At the end of the insertion tongue


76


which faces the slide


74


, the displacement element


18


′ has a displacement cam


80


. The insertion tongue


76


is intended to rest with prestress on that flat side


28


′ of the objects


28


which faces it, and to be inserted at the rear edge


30


of an object


28


in order to displace it. At the downstream end of the section


24


′ of the movement path of each reflector element


78


, and thus of the displacement element


18


′, a light-source/light-sensor unit


82


connected to the counter


56


(

FIG. 2

) is arranged in a fixed position. If, therefore, the reflector element


78


is covered by an object


28


, the light barrier formed by the light-source/light-sensor unit


82


and the reflector element


78


is interrupted, which means that during the corresponding delivery stroke of the displacement element


18


′, an object


28


is fed to the second belt conveyor


14


. If, on the other hand, the light barrier is not interrupted, this means that the displacement element


18


′ is not moving an object


28


.




The drive


22


for the displacement elements


18


′ has an intrinsically self-contained traction element


84


, for example formed by a chain. It is lead around two turn wheels


86


in such a way that the conveying run


84


′ extends in the conveying direction F between the guide rails


72


. Catching cams


88


project on alternate sides from the traction element


84


at the desired spacing A


2


for the objects


28


. When the traction element


84


is driven in the circulating direction U, the catching cams


88


in each case come into contact with the upstream end


74


′ of the slides


74


, which are located in the rest position


90


, and carry said slides


74


along in the conveying direction F until the end of the movement path


24


is reached, where the catching cams


88


run off the end


74


′ because of the deflection around the downstream turn wheel


86


. The speed v, at which the catching cams


88


are driven, corresponds to the second conveying speed v


2


. In the acceleration section of the movement path


24


between the rest position


90


of the slides


74


, in which they are held by means of a tension spring


92


, and the position of the axis of the upstream turn wheel


86


, the slide


74


is accelerated to the second conveying speed v


2


. In the section


24


′ of the movement path, which extends over a length corresponding to the spacing between the axes of the two turn wheels


86


, it maintains this speed. From the position of the axis of the downstream turn wheel


86


until the relevant catching cam


88


runs onto the end


74


′, the slide


74


is retarded, and after running off slides back again into the rest position


90


because of the force of the tension spring


92


.




In

FIG. 4

, a slide


74


is also shown at the downstream end of the section


24


′ of the movement path, from where the relevant object


28


is in each case conveyed onward by the second belt conveyor


14


. The design shown of the position-changing device


16


has the advantage that the displacement elements


18


′ do not have to be pivoted out of the region of the objects


28


, which ensures very precise positioning and transfer of the objects to the second belt conveyor


14


. Since the displacement elements


18


′ sweep over objects


28


in their rest position and during their movement counter to the conveying direction F, they do not need to be pivoted into the movement path


24


of the objects


28


for the movement in the conveying direction and in order to act on the objects


28


. They interact with the objects


28


in the manner of a free-wheel. This leads to each object being carried along reliably.




As can be seen from

FIG. 4

, the length of the section


24


′ of the movement path corresponds to the desired spacing A


2


, but can also be different. Here, too, the first conveying speed v


1


is coordinated with the second conveying speed v


2


in such a way that two objects


28


are certainly never caught by the displacement elements


18


′ and fed to the second belt conveyor


14


.




The conveying tapes, arranged beside one another, of the first belt conveyor


12


consist of resilient material, so that in the presence of objects


28


a sag can be formed between said tapes and a reference


96


matched to the insertion tongues


76


. The object


28


to be caught in each case by a displacement element


18


′ therefore rests approximately parallel to the guide rails


72


and the conveying plane of the second belt conveyor


14


.




A further embodiment of the position-changing device


16


is shown in FIG.


5


. The drive


22


is constructed as a cylinder/piston unit


20


, which is mounted in a fixed position at one end and provided at the other end with a displacement element


18


′. The cylinder/piston unit


20


is connected to a control device


26


which, for its part, is connected to a sensing device


94


for the rear edges


30


of the objects


28


arriving on the first belt conveyor


12


in the overlapping formation S


1


. The displacement element


18


′ is intended to rest on the flat side


28


′ of the objects


28


. The control device


26


controls the cylinder/piston unit


20


as a function of the desired spacing A


2


to be achieved, the second conveying speed v


2


and the signals from the sensing device


94


. In this case, the movement path


24


is defined by the flat side


28


′ of the objects


28


. A weighted roller


50


′ prevents the upstream objects


28


being carried along in relation to the displacement element


18


′.





FIGS. 6 and 7

show a further embodiment of the position-changing device


16


, in which the displacement means


18


has twelve displacement elements


18


′. These are constructed like double levers and, with their bearing part


19


of U-shaped cross section, are pivotably mounted on bearing shafts


100


protruding from a carrying disk


98


. The bearing shafts


100


extend parallel to a drive shaft


102


, on which the carrying disk


98


is seated such that it rotates with it, and are arranged to be uniformly distributed in the circumferential direction on a circle which is concentric with the drive shaft. Fixed to each of the bearing parts


19


is a bow


19


′, which is produced from a spring-steel strip and is bent like a hook at its free end. By means of a drive


22


, the carrying disk


98


is driven in rotation in the direction of rotation D in a manner coordinated with the conveying speed v


2


of the second belt conveyor


14


connected downstream of the first belt conveyor


12


. The bearing parts


19


of the displacement elements


18


′ each bear a freely rotatably mounted follower roller


104


. One end of a tension spring


108


acts on the bearing pin


106


of each follower roller


104


, and the other end, as viewed in the radial direction, is fixed further in to the carrying disk


98


. The tension springs


108


hold the follower rollers


104


in contact with the circumference of a fixedly arranged control disk


110


. The circumference of the control disk


110


forms a control cam


112


for the pivoting position of the displacement elements


18


′.




The tapes


12


′ which form the first belt conveyor


12


and which are produced from resilient material run underneath the position-changing device


16


. They are driven in the conveying direction F at the first conveying speed v


1


. They are intended to feed the flat objects


28


arriving in an overlapping formation S


1


to the position-changing device


16


. In the overlapping formation S


1


, each object


28


rests on the respectively following object, as a result of which the rear edge


30


of each object


28


is exposed in the upward direction.




Arranged above the first belt conveyor


12


and underneath the carrying disk


98


are two hold-down elements


114


, which are fixed to the machine frame


116


, on which the drive shaft


102


is freely rotatably mounted and to which the control disk


110


is also fixed. The hold-down elements


14


, which are arranged on both sides of the movement path


24


of the displacement elements


18


′, have a rectilinear guide section


114


′ which extends in the conveying direction F, and an upstream inlet section


114


″ arranged at an obtuse angle thereto. The hold-down section


114


′, against which the objects


28


are kept in contact by the resilient design of the first belt conveyor


12


, defines the movement path of the rear edges


30


of the objects


28


. The inlet section


114


′, together with the first belt conveyor


12


, forms an inlet which tapers like a wedge into the gap formed by the tape


12


′ and the hold-down section


114


″.




As viewed in

FIG. 6

, from about three o'clock—in the counterclockwise direction—to about six o'clock, that is to say vertically underneath the drive shaft


102


, the control cam


112


runs concentrically with the drive shaft


102


. Here, the corresponding displacement elements


18


′ assume a position in relation to the circular carrying disk


98


in which the hook-like end trails in relation to the follower roller


104


, and the displacement elements


18


approximately form an angle of 45° with an associated tangent to the carrying disk


98


. Approximately vertically underneath the drive shaft


102


, as viewed in the direction of rotation D, there begins a cam section


112




1


, in which the distance from the drive shaft


112


increases continuously. This is adjoined by an approximately equally long section


112




2


, in which the distance becomes smaller again. Arranged immediately after this is a section


112




3


, in which the distance increases again within a small angular range. In a region which follows the section


112




3


, the distance remains unchanged again, decreases again in a region between about four o'clock and three o'clock and becomes the same as the radius of the concentric section.




This form of the control cam


112


has the following action. As, as viewed in the direction of rotation D, a follower roller


104


approaches the section


112




1


of the control cam, the hook-like end of the displacement element


18


′ moves through between the hold-down elements


114


in the inlet section


114


″ and comes into contact with its free end on the upper flat side


28


′ of an object


28


. As a result, the hook-like end of the displacement element


18


′ is forced back resiliently, but holds the tension spring


108


and the follower roller


104


in contact with the control cam


112


. The start of the hold-down section


114


′ coincides approximately with the region in which the displacement element


18


′ comes into contact with the respective object


28


. The result of the section


112




1


of the control cam


112


is that the hook-like end of the displacement means


118


moves along the section


24


′ of the movement path, which extends at least approximately rectilinearly and in the conveying direction F. For this purpose, the displacement element


18


′ is pivoted in the clockwise direction. Since the circumferential speed of the hook-like end of the displacement element


18


′ is higher than the first conveying speed v


1


, the displacement element


18


′ comes into contact with the rear edge


30


of the leading object


28


and carries the latter along in the conveying direction F. In the section


112




2


of the control cam


112


, the relevant displacement element


18


′ is pivoted in the counterclockwise direction, the result of which is that, on the one hand, the hook-like end of the displacement element


18


′ continues to be moved along the at least approximately rectilinear section


24


′ of the movement path and, on the other hand, the trailing hook-like end of the displacement element


18


′ experiences an acceleration, as viewed in the conveying direction F. As far as the downstream end of the section


112




2


, as viewed in the direction of rotation D, the hook-like end of the displacement element


18


′, as viewed in the conveying direction F, is accelerated to the second conveying speed v


2


of the second conveyor


14


, the result of which is that the object


28


displaced in the conveying direction F by the relevant displacement element


18


′ is fed to the second conveyor at the desired second conveying speed v


2


and at the correct phase angle. The result of the third section


112




3


is that the displacement element


18


′ is pivoted in the clockwise direction, in order to move its hook-like, trailing end inward in the radial direction away from the rear edge


30


of the object


28


displaced forward. This and the following section prevent the displacement element


18


′ acting further on objects


28


.




In this embodiment, the spacing A


2


to be achieved between the rear edges


30


of successive objects


28


in the overlapping formation S


2


formed is defined by the spacing of the displacement elements


18


′ on the carrying disk


98


. This embodiment is distinguished by particularly quiet running, even at very high processing capacity.




The hold-down elements


114


prevent the objects


28


bending up when they are acted on by a displacement element


18


′. In addition, hold-down rollers


118


arranged on both sides of the first belt conveyor


12


prevent the objects


28


bending up laterally.




Of course, in this embodiment [sic] can also have a detection device which interacts with the displacement elements


18


′ and emits a signal to a counting and/or control device in each case when a displacement element


18


′ interacts with an object


28


.




It is preferable if, in all the embodiments, the frequency f at which the displacement means


18


are moved through the movement path


24


is approximately 1.2 to 1.4 times as high as the quotient of the first conveying speed v


1


and a permissible minimum spacing A


1


between the rear edges


30


of successive objects in the arriving formation S


0


or S


1


. It is further preferred for the second conveying speed v


2


to be at least approximately 2 to 4 times as high as the first conveying speed v


1


. In this case, the quotient of the second conveying speed v


2


and the desired spacing A


2


is greater than the quotient of the first conveying speed v


1


and the minimum spacing A


1


in the arriving formation S


0


or S


1


. It is further preferred for the section


24


′ of the movement path to be at least approximately 2 to 4 times as long as the permissible minimum spacing A


1


between the rear edges


30


of successive objects


28


in the arriving formation S


0


or S


1


.




Of course, it is also conceivable for the slides


74


, during their movement counter to the conveying direction F brought about by the tension spring


92


, to come immediately into contact again with their end


74


′ with a catching cam


88


, so that they are driven again in the conveying direction F immediately—without waiting in the rest position


90


.




In particular, the device shown in

FIG. 2

, preferably in combination with the apparatus illustrated in

FIGS. 3

to


7


, is also suitable for equipping each object with a transport clamp


34


.



Claims
  • 1. Apparatus for transferring flexible flat objects from a first conveyor to a discharge conveyor which is provided with transport clamps, comprising:a first conveyor; a second conveyor positioned immediately downstream of the first conveyor; a discharge conveyor positioned downstream of the second conveyor, said discharge conveyor having transport clamps arranged one behind another at a release point, a release device at the release point whereby the transport clamps can be selectively released, said discharge conveyor further comprising a drive for the transport of the transport clamps released at the release point to a pick-up point, said drive being synchronized with the second conveyor; and a position changing device which is arranged in the region of the first conveyor, the position changing device being configured to detect arriving objects, to arrange them individually in correct phase on the second conveyor and to emit a signal to control the release device in such a way that, for each object output from the second conveyor, a transport clamp is provided at the correct time by the discharge conveyor for fitting said clamp at the pick-up point with an object fed by the second conveyor.
  • 2. Apparatus according to claim 1, wherein the position changing device is further configured to control the release device such that between the release point and the pick-up point at least an equal number of transport clamps are positioned as there are objects positioned between the position changing device and the pick-up point.
  • 3. Apparatus according to claim 1, wherein the flexible, flat objects arrive on the first conveyor in an overlapping stream, and the position changing device has a displacement means which is moved along a movement path by means of a drive and, at least in one section of the movement path in relation to the conveying direction of the first conveyor, is driven by said drive of the position changing device at a higher speed than the conveying speed of the first conveyor and so as to feed each object delivered to the position changing device by means of the first conveyor to the second conveyor by striking the rear edge of such object, said second conveyor being driven at a conveying speed that is higher than the conveying speed of the first conveyor, and wherein the one section of the movement path extends at least approximately rectilinearly and at least approximately in the conveying direction, and the drive of the position changing device drives the displacement means in the one section of the movement path at a speed which, at least as the objects are transferred to the second conveyor, is at least approximately equal to the conveying speed of the second conveyor.
  • 4. Apparatus according to claim 3, wherein the drive of the position changing device is controlled as a function of the conveying speed of the second conveyor and a desired spacing of the objects on the second conveyor, and such that its phase angle with respect to the second conveyor can be adjusted.
  • 5. Apparatus according to claim 3, wherein a drive element drives the first conveyor in such a way that the quotient of the conveying speed of the second conveyor and the desired spacing is greater than the quotient of the conveying speed of the first conveyor and a minimum spacing between the rear edges of successive objects in the arriving overlapping stream.
  • 6. Apparatus according to claim 3, wherein a detection device interacts with the displacement means and emits the signal to a counting and/or control device in each case when the displacement means interacts with an object.
  • 7. Apparatus according to claim 3, wherein the position changing device includes a guide means extending in the conveying direction for the displacement means, and the drive of the position changing device includes an endless traction element which is driven so as to circulate at least approximately at the conveying speed of the second conveyor and has catching elements which are arranged one behind another at least approximately at a desired spacing of the objects on the second conveyor and interact with the displacement means in the conveying direction.
  • 8. Apparatus according to claim 7, wherein the displacement means includes at least two displacement elements which are driven alternately in the conveying direction.
  • 9. Apparatus according to claim 3, wherein the displacement means includes a number of displacement elements which are driven so as to circulate along a circular path and whose position can be controlled such that they are moved along the one section of the movement path which extends approximately rectilinearly and at least approximately in the conveying direction.
Priority Claims (1)
Number Date Country Kind
2986/97 Dec 1997 CH
PCT Information
Filing Document Filing Date Country Kind
PCT/CH98/00561 WO 00
Publishing Document Publishing Date Country Kind
WO99/35072 7/15/1999 WO A
US Referenced Citations (7)
Number Name Date Kind
3955667 Muller et al. May 1976 A
4201286 Meier May 1980 A
4333559 Reist Jun 1982 A
4550822 Meier Nov 1985 A
4667950 Linder et al. May 1987 A
4905981 Reist Mar 1990 A
5669604 Hansen Sep 1997 A
Foreign Referenced Citations (6)
Number Date Country
631 410 Aug 1982 CH
677778 Jun 1991 CH
3903610 Sep 1989 DE
0254851 Feb 1988 EP
2089329 Jun 1982 GB
WO 9503989 Feb 1995 WO