EP0179992B1 - Process and device for collecting and stacking sheet-like articles - Google Patents

Description

28. The invention relates to a method and a device for the stack-forming collection of sheet-like products, in particular signatures for the collation of book blocks following a printing press.

In one or one of the methods and apparatus described in the earlier German patent application P 34 10 862.9 (DE-OS 34 10 862) of the applicant for forming discrete stacks from a stream of sheet-like products, a certain number of these products is conveyed into a compartment of the paddle wheel . Rejection and control devices are provided for separating the products of one stack from the next stack. After a predetermined angular rotation of the paddle wheel, the stacks are then pushed radially outward, preferably with the compartments in a horizontal position, and transported away by a transport means.

Such a method and such a device are also known from DE-PS 17 61 594, in which a shingled stream of sheet-like products is assumed to be supplied. The products in the shingled stream must be positioned very precisely and must not shift because otherwise the trouble-free transfer of the first and last sheet or sheet of the stack is at risk. The stream of shingles must be conveyed from a horizontal plane from the side into the compartments of the paddle wheel. The entire opening width of a compartment is therefore not available for the insertion of the sheets, so that either the speed of rotation of the paddle wheel must be selected to be relatively low or the transport speed of the shingled stream must be selected to be relatively high. Stacks are also formed in the individual compartments, for the separation of which a deflection device is provided during feeding.

The stacks are removed when the partition walls are in a horizontal position by pushing them out onto a means of transport. In this known device, the sheet-like products must therefore be fed to the paddle wheel in a horizontal arrangement and also removed therefrom. This means that the angle of rotation range over which the stacks are transported in the paddle wheel is very small, so that space problems can arise in the arrangement. This also results in a speed limitation for the rotary movement of the paddle wheel, since if the rotational speed is too high, the period between feeding and removal becomes too short and the last stacking sheets may not yet be safe enough to lie on the stack when the removal process begins.

To collect occasionally transported sheet-shaped products, it is known from BE-PS 688 119 to also feed these products laterally to the compartments of the paddle wheel. Two spaced, constantly rotating circular disks, the common axis of which is arranged parallel to the axis of the paddle wheel and which reaching into the interior of the compartments are intended to prevent the sheets from forming arcs or becoming wavy when sliding into the predetermined compartment. Accordingly, the disks act on each sheet such that the sheets sliding into the compartment conform to the curvature of the disks. The disks should also hold down the stack forming in the pocket with their outer surface. In order to prevent the first sheet of the next stack from hitting a partition or entering the previous compartment, it is proposed that the speed of rotation of the paddle wheel be increased suddenly for a short time so that the next compartment is open when the first bottom of the stack enters the Area of the paddle wheel. Such a device is expensive. The brief, sudden increase and deceleration of the rotational speed creates vibrations that can impair stacking. The stacks are also removed from the paddle wheel with the respective partition wall in a horizontal position.

It is also known to use a paddle wheel for the stack-forming collection of sheet-like products, which has compartments for the sheet-like products and a stop rail at the bottom, which leads to the transport direction; ie a conveyor belt downstream of the paddle wheel is inclined. The sheet-shaped products are fed from above, rotated in the paddle wheel, braked to a speed of essentially zero on the stop rail, then accelerated again and moved outward under the action of friction. This movement is imprecise, and the well-known paddle wheel can only be used for low speeds, ie up to approx. 8000 revolutions.

A method and a device of the type described in the preamble of claims 1 and 28 can be found in EP-A-O 067 399. In this prior art, the paddle wheel arranged above a transport means formed by a delivery belt is fed with folded, sheet-shaped products by a feed device. The products released by the feed device in the form of a belt guide fall into the compartments of the paddle wheel from above and are deposited on the delivery belt in the form of a scale track after about a quarter turn. To lift the products out of the compartments, parallel lifting or stripping belts are provided above the delivery belt in a rake-like manner in the paddle wheel formed by a plurality of disks arranged at a corresponding distance from one another. These lifting belts run straight, tangential to a circle defined by the shelves and cut the compartments that are currently in a certain angle of rotation range. In this embodiment, it is disadvantageous that the lifting belts push the sheet-shaped products outwards at a progressive speed, and there is also a relative speed between the lifting belts and the sheet-shaped products, so that friction also occurs in this area. This accelerates the sheet-like products, causing them to bend. There is an uncontrolled falling out of the products from the compartments and consequently also an inaccurate placement on the transport means. To remedy this deficiency, additional devices are provided in this known embodiment, with which the sheet-shaped products are adjusted on the conveyor belt. As a result, a considerable additional outlay is specified both in terms of method and device.

The invention is based on the object of a method and a device which are specified in the preamble of claims 1 and 28, respectively To create the type that allows the sheet-shaped products to be led out of the compartments of the paddle wheel without accelerating the sheet-shaped products, even at high speeds, to form a reliable stack in a simple manner.

This object is solved by the features in the characterizing parts of claims 1 and 28, respectively. Advantageous developments of the invention are characterized in the subclaims.

The method according to the invention and the device according to the invention are essentially independent of the special type of feeding, ie the sheet-like products can be fed vertically or horizontally, singly or in a stream of flakes. The supply can thus be selected according to the circumstances.

The removal of the sheet-shaped products in the form of sheets or leaves from the paddle wheel does not have to be carried out in a horizontal position, since the sheet-shaped products are held in the paddle wheel and are pushed outwards in a precise orientation and positioning in the compartments to the desired removal point. In this way, a sufficiently large angle of rotation range can always be realized, and the stack formation can be carried out at high working speeds.

The invention is essentially based on the fact that the leaf-shaped elements in the paddle wheel are shifted exactly and continuously. The synchronization of the pushing out and removal movement from the impeller with the impeller rotation is particularly favorable. A time-adapted transport of the collected sheets or the stack is expedient.

According to the invention, individual blades are preferably transported in the paddle wheel and continuously pushed or pushed radially outward in the paddle wheel, their front edge moving from the shelf at a first radial distance from the axis of rotation of the paddle wheel to the outer edge of the respective partition wall with a second radial distance. The removal process is thus initiated while the sheets are in the compartments of the paddle wheel, and the front or the inner edge of the sheets has reached the outside of a compartment at the very moment in which the sheet has this compartment for further transport or should leave the stack formation. The turning and removal process are thus nested in time, which can save time. This combined procedure is made possible in particular by the fact that the sheets in the compartments are always arranged in a well-defined position.

The displacement of the blades radially outwards takes place at such a speed that the sections of the arcuate path between two partition walls of the impeller each have the same length. The leading edges of the sheets then do not move at a certain radial distance from the axis of rotation at the circulating speed of the shelf, but at a slower but constant speed which is predetermined by these geometric conditions. The guidance of the blades is simplified in this way, and the blades can leave the paddle wheel in a particularly safe and trouble-free manner. These geometrical relationships can be achieved in particular by suitable inclination of the shelves. The sheets, ie the sheet-shaped products, are expediently pressed against the respective partition wall in the region of their front edge, so that the sheets are held somewhat jammed in the compartments and force the speed jump from the shelf circulating speed to the lower speed along the curved path. The relative speed between the scraper belt and the leading edge of the blade is preferably zero in the gusset formed by the scraper belt and blade during the downward movement of the blades.

The guidance of the sheets in the compartments is improved in that the partitions are convex or arcuate as a slideway for the sheet-shaped products and that these are supported during the radially outward movement in the area of the trailing edge on a moving stop. As a result, the displacement movement of the sheets can take place in a particularly targeted manner, in particular when the compartments are more inclined during removal.

The sheet-shaped products preferably move in free fall after leaving the paddle wheel and are then stacked and transported away in stacks. The last sheet of a stack is expediently pushed onto its rear edge when it leaves the region of the impeller with its front edge, and the first sheets of the subsequent stack are held for a short time while the previous stack is being transported away. A particularly good separation of the individual stacks is achieved in this way.

The procedural steps are expediently synchronized with the rotation of the paddlewheels, so that the movement sequences are probably coordinated with one another, which is very important especially at the high working speeds. The radial displacement of the blades does not necessarily have to take place during the entire dwell time in the paddle wheel, but rather the blades can first be rotated and then additionally displaced during a second rotating section. This results from the geometric arrangement of the feed to the paddle wheel and the downstream means of transport.

The exact guidance of the sheet-like products in the paddle wheel is advantageously achieved by a scraper belt, which has a special geometric shape and guides the sheets outwards in the fan. In the area of engagement with the blades, the belt is designed in the form of an arcuate path, the sections of which between two partition walls of the paddle wheel each have the same length and the speed of the stripping belt is selected such that a certain point on the belt covers such a distance per cycle time travels. The cycle time is the rotation time of the paddle wheel divided by the number of compartments. This measure ensures that the leading edge of the sheets has no relative speed to the scraper belt.

The scraper belt is preferably driven by a drive wheel which runs with the paddle wheel. As a result, the synchronization of the rotation and displacement movement is particularly simple. The drive wheel is expediently arranged coaxially with the paddle wheel. According to one In an advantageous further development of the invention, the partition walls in the impeller are not made compact, but consist of at least two sections or fingers arranged separately from one another in the axial direction, and the scraper belt is arranged in the axial space between these sections. The structure of the device according to the invention is particularly simplified by the common drive, and the arrangement is very space-saving.

The scraper belt expediently runs over two guide rollers, one of which is arranged radially within the imaginary extension at the beginning and the other behind the end of the preferably arcuate path. Between the two guide rollers, a convexly curved guide rail, preferably a Teflon or chrome-plated sheet metal, is provided, over which the band runs and which is shaped in this section in accordance with the desired course of the band. The web shape is chosen so that the sheet-like products are pinched because of the very small inlet angle.

The moving stop for supporting the trailing edges of the blades during part of the outward movement is advantageously formed by a conveyor belt which moves in the area of engagement with the sheet-shaped products in accordance with the direction of rotation of the paddle wheel, i.e. in the same direction in which the Move trailing edges. This conveyor belt preferably cuts the circle formed by the trailing edges of the sheet-like products, so that the sheets are continuously held more firmly when they are pushed out of the compartments.

Advantageously, the transport means arranged downstream of the paddle wheel arrangement additionally has a faster chain with stops for the finished stacks, the drive of which is synchronized with the rotation of the paddle wheel so that a stop pushes the rear edge of the last sheet-shaped product when it leaves the paddle wheel with its front edge. In this way, collected stacks can be transported away particularly quickly and reliably.

To improve the separation of the first sheets of a stack from the previous stack, a holding element is arranged in a preferred embodiment of the invention in addition to the scraper belt on the end product of the arcuate web, which preferably has an inclined pin that can be moved downwards. The pin is pushed down and holds the first preferably one or two sheets of a stack and is withdrawn again when there is no longer a risk that these sheets will be carried by the stop of the means of transport. The movement of the pin is also synchronized with the rotation of the paddle wheel. It is expediently driven by a crank or a cam disk.

Fig. 1

schematisch eine Rückansicht einer erfindungsgemäßen Schaufelradvorrichtung,

Fig. 2

schematisch eine Ansicht in Pfeilrichtung eines Schnitts längs der Linie A-B in Fig. 1, wobei außerdem ein Transportmittel zum Wegtransportieren eines gesammelten Stapels der blattförmigen Produkte dargestellt ist,

Fig. 3

ein Diagramm, das den zeitlichen Verlauf der Transportgeschwindigkeit der Blätter veranschaulicht,

Fig. 4

ein Diagramm, das die Steuerung eines als Halteelement für die ersten blattförmigen Produkte eines Stapels vor der Freigabe vom Schaufelrad dienenden Stifts veranschaulicht,

Fig. 5 bis 8

erfindungsgemäße Ausgestaltungen zur Stapeltrennung im Schuppenstrom,

Fig. 9 und 10

eine Anordnung zur Stapelbildung ohne vorhergehende Schuppenbildung.

The invention is explained below with reference to an embodiment shown in the drawing. Show it:

Fig. 1

schematically shows a rear view of a paddle wheel device according to the invention,

Fig. 2

1 schematically shows a view in the direction of the arrow along the line AB in FIG. 1, a transport means for transporting away a collected stack of the sheet-like products also being shown,

Fig. 3

1 shows a diagram which illustrates the time course of the transport speed of the sheets,

Fig. 4

FIG. 2 shows a diagram which illustrates the control of a pin serving as a holding element for the first sheet-like products of a stack before release from the impeller, FIG.

5 to 8

refinements according to the invention for stack separation in the shingled stream,

9 and 10

an arrangement for stacking without previous dandruff.

The invention can advantageously be used to form blocks from single sheets or signatures, which must be carried out, for example, in the production of books following rotary printing presses and feeding the sheets to perfect binding machines.

1 schematically shows a rear view of a paddle wheel device according to the invention, in which the feed device and the transport means for transporting the stacks away are not shown for a better overview. Since the device shown is constructed essentially symmetrically to the section line AB, for the sake of clarity, essentially only the parts of one half are provided with reference numerals. The paddle wheel 2 has on the outside a relatively thin circular disk-shaped protective cover 4, the diameter of which is approximately equal to the largest diameter of the parts located within the cover (2 x R2). Between the two caps of the protective cover there is the cylindrical paddle wheel base body 8 with a radius R1, which has a step in the middle, ie an area 30 with a smaller diameter. Axially outside of the stepped area 30, the bucket wheel base carries blades or fingers 6 serving as dividing walls, the number of which is selected according to the desired number of cycles and the diameter of the bucket wheel. In the exemplary embodiment shown, two blades arranged at an axial distance from each other serve as a partition. The width and wall thickness of the blades, which are preferably made of flat material, is selected in accordance with the pressure required and the loads when the blades are pushed out radially. The blades are each arranged at an angle β with respect to the cylindrical base body 8 and bent slightly convex with respect to the latter as a slideway for the front edges of the sheet-like products, which will be explained later. The angle β is determined in particular from the speed of rotation and the arrangement of the feed device and the removal location. In the embodiment shown, the angle β is chosen such that the blades 6 are positioned approximately horizontally below the axis of the blade wheel 2. However, this alignment is not mandatory in the device according to the invention. The blades or partitions 6 form compartments, the shelves 10 of which are formed by the outer surface of the cylindrical base body 8.

A convex outwardly curved guide or guide rail 40 (for example made of Teflon or chromed sheet metal) is arranged below the region 30 of the cylindrical base body 8 and extends over part of the angle of rotation range through which the sheet-shaped products pass and from a radial distance extends from about R1 to a radial distance of about R2 from the axis of rotation of the impeller 2 in the direction of rotation. The shape of the guide rail 40 is selected in accordance with the desired path of the conveyor belt, that is to say in the form of an arc in the example shown. In the lower region of the cylindrical base body 8 there are also two guide rollers 34, 36. The guide roller 34 is arranged in front of the guide rail 40 with respect to the impeller rotation and its circumference at the radially outermost point is approximately at a distance R1 from the axis of rotation. The other guide roller is located on the other side of the guide rail 40 and is therefore arranged downstream in terms of movement. It is arranged somewhat radially within the imaginary extension of the arcuate path over the area where the blades leave the impeller, and its circumference lies radially at the extreme point within this imaginary line. The scraper belt 32 runs over the stepped region 30 of the cylindrical base body of the impeller 2 and is guided back to the region 30 via the guide rollers 34, 36 and the guide rail 40. The geometric path of the stripper belt is determined by the arrangement, number and diameter of the guide rollers and by the arrangement and shape of the guide rail. In the area of the guide roller 34, the scraper belt runs with a very small angle with respect to the blades 6. The material thickness and type of the scraper belt are chosen so that it engages with the blades in the desired manner and moves them along the arcuate path.

A pin 70 serving as a holding element or support element is arranged next to the scraper belt. This pin is inclined at an acute angle γ to the sheet-shaped products when they are at the end of the arcuate path 38 of the stripping belt 32 and also at an acute angle γ 'to the stripping belt 32. The pin 75 is longitudinally displaceable in a guide 74, for example a sleeve. A crank drive 72 is provided for driving the pin 70; alternatively, for example, a cam disc * can be used. In the rest position, the pin 70 is retracted radially within the scraper belt 32 and can be extended to the position 70 'shown in FIGS. 2 and 4, which is shown in broken lines.
^* an electromagnet or the like synchronization means

The device is further explained below, in particular with reference to FIG. 2, using the procedural movement sequence. The sheet-like products 14, which are, for example, printed signatures in the exemplary embodiment described, leave a printing machine (not shown) after a cutting and pulling device and are to be collected into blocks 16. Arranged above the impeller 2 is a pulling device 18, which in the present example consists of two counter-rotating rollers and conveys the individual signatures 14 into the compartments 12 of the impeller 2.

The falling signatures 14 hit the shelves 10 after passing through the pulling device 18 due to the force of gravity and feed speed and come to rest against the blades which are somewhat curved outwards. After two cycle times and one revolution by an angle α 1, the signatures are clamped between the scraper belt 32 and the respective partition wall because of the very small inlet angle and are fixed in their position. As the figure shows, the scraper belt 32 is geometrically guided so that the distance Δ S between two adjacent partitions is always the same. The scraper belt runs at the speed v _AB = Δ S / ts, where ts is the cycle time per signature. In this way it is achieved that the leading or leading edge of the signatures each move without relative speed with respect to the scraper belt 32. In accordance with the prevailing geometrical circumstances, the signatures undergo a jump in speed from the higher circumferential speed v _{SR of} the paddle wheel at radius R1 to the lower speed v _{AB of} the scraper belt 32 when the stripper belt 32 engages. This step in speed is shown schematically in FIG. 3. The speed is plotted along the ordinate of this diagram and the angle of rotation α is plotted along the abscissa.

The signatures are guided in the gusset between the partition walls, ie the blades 6 and the scraper belt 32, in such a firm and well-adjusted manner that they leave the blade area exactly at the angle of rotation α 2 with the front edge and move down in free fall. Therefore, in the device according to the invention, the position of the signatures is defined precisely enough at any speed, so that correct stack formation is ensured.

In the exemplary embodiment shown, a movable stop in the form of a conveyor belt 50 is additionally arranged obliquely below the impeller 2. The conveyor belt rotates with such a sense of rotation and such a belt speed that it runs along with the trailing edges of the signatures on the side facing the paddle wheel. Due to its inclination, it presses the signatures as they move out of the compartments against the scraper belt and the respective partition walls and thus supports the guidance of the signatures.

Below the paddle wheel 2, a conveyor belt 60 is used to transport the stacks away. A chain 61 runs therein, which has spaced stops or fingers 62, against which the finished stacks 16 come into contact during further transport. In the device according to the invention, the speed of the conveyor belt 60 can be chosen essentially freely and, in particular, independently of the speed v _{AB of} the scraper belt 32, since it only serves to form flakes. The chain 61 must, however, have a synchronization with the number of cycles and rotational speed etc. of the device according to the invention in order to ensure the sequence, in order to ensure trouble-free transport of the finished stacks away. In the embodiment shown, the synchronization is chosen such that the fingers 62 of the chain 61 the rear Push the end of the last signature 14 of a stack or block 16 each time when it just leaves the blade area with its front edge.

The pin 70 serves to improve the separation of the signatures of successive stacks 16. The pin 70 is moved out when the last signature of a stack is pushed on and prevents the next released signature from getting into the area of the stop 62 and being transported with the previous block becomes. The pin 70 expediently holds back the first two or three signatures of the subsequent block until the stop 62 has moved far enough to the right in FIG. 2, and is then withdrawn again.

FIG. 4 illustrates the control of the pen 70 using an example in which four signatures 14 are combined to form a block 16. The crank drive 72 of the pin 70 is synchronized with the impeller 2. At the beginning of a clock cycle, which runs from 1 to 4 in the example shown, the pin 70 has moved out and holds the signatures 1 and 2 in the gusset between the stripper 32 and the partition 6. Until shortly before the third signature arrives, the first two signatures of a stack are therefore kept above the conveyor belt 60 and thus at a distance from the stop 62. After finger 70 is withdrawn, the first two signatures are released and fall onto conveyor belt 60. The last two signatures of a stack fall freely onto conveyor belt 60 and are then pushed together by stop 62 and transported on. In this FIG. 4, the course of the scraper belt with respect to the pin 70 is indicated with the reference symbol 32.

5 shows a further advantageous possibility of separating signatures 14 of successive stacks 16 from one another and thus preventing the next signature 14 leaving the paddlewheel 2 from still getting into the area of the stop 62 and thus being transported unintentionally, and that on the other hand entrainment between the signatures 14 takes place. In this case, a block 101 provided with a friction lining is provided, which is raised to hold or brake the first signature 14 of a new stack 16, so that this first, as well as the subsequent signatures 14, come to rest on this block 101. If the previously formed stack 16 to be transported away is far enough away that subsequent signatures are no longer to be taken away due to static friction, block 101 is lowered, whereby the signatures are released and can be transported away by the next stop 62 of the conveyor belt 60. The block 101 can expediently be raised and lowered via a crank mechanism 102, which runs synchronously with the rotation of the paddle wheel, this crank mechanism 102 ensuring that the block 101, in its raised state, executes a movement in the direction opposite to the transport direction of the conveyor belt 60 . This effectively separates the individual stacks 16.

Alternatively, friction for stack separation can also be caused by an additional conveyor belt (not shown) are caused, which has friction linings that are raised analogously to block 101.

6 shows a possibility of stack separation, in particular in connection with a method in which the signatures 14 leaving the paddle wheel initially form a stream of shingles. In order to prevent the subsequent signature from being dragged along when a stack 16 is pushed together by the finger 62, which can be done by the overlap of the signature with the stack to be pushed together and the associated static friction, the invention provides that one or more signatures of a stack in the stream of shingles transported at a uniform speed are clamped in a force-fit manner, while the signatures in front of them are moved away at a higher speed and pushed together into a stack. In this way, the signatures are separated safely and without the risk of dragging subsequent signatures with them, thereby forming discrete stacks. In order to achieve different speeds of the shingled stream and the transport away, it is provided to use two separate conveyor belts 60 and 105. The conveyor belt 105 determines the speed of the shingled stream and the belt 60 determines the higher speed of the transport away for pushing the stacks 16 together using the fingers 62. In the area of the belt 105, a device for clamping the signatures 14 is now provided according to the invention. Fingers 106, 107 are arranged above and below the scale stream, which are synchronized via separate bands 108, 109 move with the shingled stream and hold it tight until the previous stack is so far away that there is no longer any fear of being carried away. It is also advantageous if the belt 105 runs in a plane that is higher than the plane of the belt 60. This creates a step in front of the belt 105, which also contributes to safe stack separation.

In an alternative embodiment, a finger can also be used on one side of the scale flow and a conveyor belt on the other side for clamping the signatures (not shown).

FIG. 7 shows how a gripper 110 can also be used for stack separation. This gripper 110 grips the first signature 14 of a stack 16 and holds it until the stack 16 has been pushed together and transported away.

A particularly simple gripper construction is shown in FIG. 8, the gripping forces being obtained by bending the signature 14. This bending takes place through a corresponding arrangement of the conveyor belt 60 for the stacks 16 and the belt 111 for the gripper 110 with respect to the plane of engagement of this gripper 110. The coupling in and out can be controlled by slightly changing the geometric conditions of this arrangement.

In an advantageous development of the invention shown in FIGS. 9 and 10, the problems with stack separation are avoided in that the signatures 14 immediately form a stack 16 when leaving the paddle wheel 2 without forming a scale, which stack is subsequently transported away by fingers 62 moved by means of the belt 60. To this end, it is essential to the invention that the signatures 14 are braked to the speed v = o by a scraper 120 before leaving the impeller 2 and subsequently fall onto the stack in free fall. The synchronization of paddle wheel 2 and transport fingers 62 is set such that a finger 62 transports the stack 16 away when the predetermined number of signatures has been reached and the first signature of the following stack is still in the balance. If further signatures 14 continuously fall at the beginning of the transport away, it is advantageous if a holding device is also provided here which prevents the falling signatures 14 from being carried along by the stack 16. The holding device can be designed in the manner already described, such as by a gripper, by friction (as shown in FIG. 10 under reference number 125) or by suction fingers.

It is essential to the invention that, in contrast to a shingled stream, the holding takes place at a speed of the signatures of v = o, as a result of which the holding forces are very low.

In order to achieve the most accurate possible stack formation of the signatures 14 falling in free fall, a support plate 130 is provided which determines the trajectory of the signatures 14. This support plate 130 is arranged behind the falling signatures 14 as seen in the direction of movement of the transport means 60.

Depending on the speed at which the stacks 16 are transported away and the speed of the impeller 2, scale formation can again occur in this arrangement, but the individual scales consist of stacks 16. It is thereby achieved that the belt 60 can move at a reduced speed with the same number of stacks, since the distances between the individual stacks 16 are very small, or else a higher throughput is achieved at the same belt speed.

Claims (46)

1. Process for collecting into stacks sheet-like products (14), in particular signatures for assembling inner books downstream of a printing machine, wherein the sheet-like products (14) are conveyed in compartments (12) formed by approximately radially to tangentially disposed dividing walls (6) of a continuously rotating bucket wheel (2) during a predetermined angular rotation of the bucket wheel (2), during rotation past a predetermined swing angle region in the bucket wheel (2) have their leading edges pressed by the compartment base (10) continuously outwards towards the outer edge of the dividing wall (6) and after leaving the bucket wheel are transported away,
   characterised in that
   the sheet-like products (14) are guided by their leading edges over a path (38) which is so curved and cuts the compartments (12) in such a manner that they are pressed outward at a constant reduced speed.
2. Process according to claim 1,
   characterised in that
   the sheet-like products (14) are pressed radially outwards at such a speed that, in a notionally stationary bucket wheel (2), the portions of the curved path (38) between each two dividing walls (6) of the bucket wheel (2) have the same length ( ΔS).
3. Process according to claim 1 or 2,
   characterised in that
   the leading edges of the sheet-like products during their outward movement are guided along the dividing walls (6) serving as a guideway.
4. Process according to one or more of claims 1 to 3,
   characterised in that
   the sheet-like products (14) are firmly clamped in the region of their leading edge between a stripper band (32) forming the curved path (38) and the respective dividing wall (6) serving as a support, with the sheet-like products (14) being slidable outwards along said dividing walls (6).
5. Process according to one or more of claims 1 to 4,
   characterised in that
   during part of the radially outward-directed movement the sheet-like products (14) are supported in the region of their trailing edge on a co-travelling stop (50).
6. Process according to one or more of claims 1 to 5,
   characterised in that
   after leaving the bucket wheel (2) the sheet-like products (14) are free-falling.
7. Process according to one or more of claims 1 to 6,
   characterised in that
   after leaving the bucket wheel (2) the sheet-like products (14) are stacked and transported away in stacks.
8. Process according to claim 7, wherein the sheet-like products form staggered stacks below the bucket wheel which are then transported horizontally away,
   characterised in that
   the last sheet-like product (14) of a stack is nudged at its trailing edge as its leading edge leaves the region of the bucket wheel (2), and the staggered stack is then pushed together and transported away.
9. Process according to claim 8,
   characterised in that
   the first sheet-like product(s) (14) of a staggered stack is (are) retained in the region of the bucket wheel (2) for a specific period of time after completion and during the start of transporting away of the preceding stack.
10. Process according to claim 9,
    characterised in that
    retention of the first sheet-like products (14) of a stack is effected in synchronism with the rotation of the bucket wheel (2).
11. Process according to claim 9 or 10,
    characterised in that
    retention of the first sheet-like products (14) of a staggered stack is effected by means of friction.
12. Process according to claim 11,
    characterised in that
    the friction is generated by cyclically raised friction linings of a conveyor belt.
13. Process according to claim 11,
    characterised in that
    the friction is generated by a cyclically raised lifting block (101) fitted with a friction lining.
14. Process according to one or more of claims 1 to 7, wherein the sheet-like products after leaving the bucket wheel form a staggered stream,
    characterised in that
    one or more sheet-like products (14) of a stack are force-lockingly clamped in the staggered stream conveyed at uniform speed, while the sheet-like products (14) lying in front are moved away at a higher speed and are pushed together into a stack (16).
15. Process according to claim 14,
    characterised in that
    clamping of the sheet-like products is effected by fingers (106, 107) which are uniformly moved therewith and are disposed above and below the staggered stream.
16. Process according to claim 14,
    characterised in that
    clamping is effected on one side of the staggered stream by a finger and on the other side by a belt.
17. Process according to claim 14,
    characterised in that
    the back end of a sheet-like product is held by means of a co-travelling gripper (110).
18. Process according to one or more of claims 14 to 17,
    characterised in that
    acceleration of the sheet-like products lying in front of the clamped sheet-like products is effected by means of a belt and/or an additional stop.
19. Process according to one or more of claims 14 to 18,
    characterised in that
    acceleration is effected in a pressure-relieved region for the sheet-like products to be accelerated by introducing a step in the direction of transport.
20. Process according to one or more of claims 1 to 7,
    characterised in that
    the sheet-like products, on leaving the bucket wheel, without forming a staggered configuration, immediately form a stack which is transported away by means of a conveyor finger (62).
21. Process according to claim 20,
    characterised in that
    the sheet-like products (14) for non-staggered stack formation are, prior to leaving the bucket wheel (2), slowed down by a stripper (120) to the speed v = 0 and then fall freely onto the stack (16).
22. Process according to claim 20 or 21,
    characterised in that
    depending upon the transport speed and the rotation speed of the bucket wheel, a staggered stream comprising individual stacks (16) is formed.
23. Process according to one or more of claims 20 to 22,
    characterised in that
    the first sheet-like product of each stack (16) is retained at the speed v = 0 to prevent its being carried along by the stack (16) moving away therefrom.
24. Process according to claim 23,
    characterised in that
    the first sheet-like products (14) of each stack (16) are retained by a gripper (125).
25. Process according to claim 23,
    characterised in that
    the first sheet-like products (14) of each stack (16) are retained by friction with the aid of a liftable friction lining.
26. Process according to claim 23,
    characterised in that
    the first sheet-like products (14) of each stack (16) are retained by a suction finger.
27. Process according to one or more of claims 24 to 26,
    characterised in that
    retention to prevent subsequent sheet-like products (14) from being carried along by stacks (16) being moved away is effected cyclically and in synchronism with the bucket wheel (2).
28. Apparatus for collecting into stacks sheet-like products, in particular signatures for assembling inner books downstream of a printing machine, and in particular for carrying out the process according to one of claims 1 to 27, having a feed device (18) for the sheet-like products (14), a bucket wheel (2) downstream of the feed device (18) and having compartments (12) formed by dividing walls (6) which extend approximately radially to tangentially from a cylindrical basic element (8), as well as transport means (60) downstream of the bucket wheel (2) for carrying away the sheet-like products, with the dividing walls (6) each comprising at least two axially spaced portions and with at least one stripper band (32) being guided in the gap between the portions of the dividing walls (6) in such a manner that, within a predetermined swing angle region of the bucket wheel (2), it extends, cutting each of the compartments running through said region, approximately tangentially to the basic element (8) of the bucket wheel (2), said element forming compartment bases (10) and having a first radius (R1) from the bucket wheel axis of rotation, outwards at least as far as a circle determined by the outer edges of the dividing walls (6) and having a second radius (R2), and that the stripper band (32) is moved in the same direction of rotation as the bucket wheel (2),
    characterised in that
    the stripper band (32), in its region cutting the compartments (12), is guided over a guide rail (40) of such a convex curvature that all the band portions lying between each two dividing walls (6) have the same length ( Δ s), and that the speed (v_AB) of the stripper band (32) is equal to the length ( Δ s) of the band portions divided by the cycle time (t_s), with the cycle time (t_s) being equal to the period of one revolution of the bucket wheel (2) divided by the total number of compartments (12).
29. Apparatus according to claim 28,
    characterised in that
    the stripper band (32) forms such an acute angle with each of the dividing walls (6) that the sheet-like products (14) are conveyed each clamped in the region of their leading edges first located on the compartment base (10) formed by the bucket wheel basic element (8) between the relevant dividing wall (6) and the stripper band (32).
30. Apparatus according to claim 28 or 29,
    characterised in that
    for driving the stripper band (32) a driving wheel is disposed coaxially to the bucket wheel (2) and rotates with said bucket wheel.
31. Apparatus according to one or more of claims 28 to 31,
    characterised in that
    the stripper band (32) has two guide rollers (34, 36), that one guide roller (34) at the start of the predetermined swing angle region is disposed in front of the guide device (40) and its outer periphery at its outermost point is at a distance corresponding substantially to the first radius (R1) from the axis of rotation of the bucket wheel (2), that the other guide roller (36) is disposed behind the end of the guide device (40) and its outer periphery at its outermost point is at a distance from the axis of rotation of the bucket wheel (4) which is greater than the second radius (R2) preferably corresponding to the outer radius of the bucket wheel (4) and at the same time is smaller than the distance of the notional extension of the band region (38) which is in engagement with the sheet-like products (14).
32. Apparatus according to one or more of claims 28 to 31,
    characterised in that
    the dividing walls (6) are curved as a guideway for the leading edges of the sheet-like products.
33. Apparatus according to one or more of claims 28 to 32,
    characterised in that
    a co-travelling stop (50) is provided which supports the sheet-like products (14) in the region of their trailing edges during part of the outwardly directed movement.
34. Apparatus according to claim 33,
    characterised in that
    the co-travelling stop (50) is formed by a conveyor belt which, in the region of engagement with the sheet-like products, moves in accordance with the direction of rotation of the bucket wheel (2).
35. Apparatus according to claim 34,
    characterised in that
    the conveyor belt (50), in the region of engagement with the sheet-like products (14), cuts the circle formed by the latter's trailing edges.
36. Apparatus according to one or more of claims 28 to 35,
    characterised in that
    the transport means (60) has a rotating chain (61) and stops (62) are provided for each of the completed stacks (16).
37. Apparatus according to claim 36,
    characterised in that
    the drive of the stops (62) is synchronised with the rotation of the bucket wheel (4), with a stop (62) nudging the trailing edge of each last sheet-like product (14) as the leading edge of the latter leaves the bucket wheel (2).
38. Apparatus according to one or more of claims 28 to 37,
    characterised in that
    disposed next to the stripper band (32) at the end of the region (38) of engagement with the sheet-like products is a holding element (70) which retains the first sheet-like products (14) of a stack (16) for a specific period of time relative to the last sheet-like product of the preceding stack.
39. Apparatus according to claim 38,
    characterised in that
    the holding element (70) is an inclined pin which is slidable outwards beyond the outer radius (R2) of the bucket wheel (2).
40. Apparatus according to claim 39,
    characterised in that
    a drive synchronised with the rotation of the bucket wheel (2) is provided for the pin (70).
41. Apparatus according to one or more of claims 28 to 40,
    characterised in that
    disposed in the region below the bucket wheel (2) and in front of the transport means (60) is a holding device which retains each first sheet-like product (14).
42. Apparatus according to claim 41,
    characterised in that
    the holding device takes the form of a block (101) which is provided with a friction lining and may be cyclically raised and lowered by means of a crank mechanism (102) in such a manner that in its raised state the sheet-like product (14) is lifted and the block (101) executes a movement in the opposite direction to the transport direction of the transport means (60).
43. Apparatus according to claim 41,
    characterised in that
    the holding device takes the form of a pair of fingers (106, 107), of which one finger (106) is disposed above and the other finger (107) is disposed below a staggered stream formed by the sheet-like products (14), and that the sheet-like products (14) are clampable between the fingers (106, 107).
44. Apparatus according to claim 43,
    characterised in that
    the plane of the staggered stream is disposed above the plane of the transport means (60) so that the sheet-like products (14) pass onto the transport means (60) by way of step.
45. Apparatus according to claim 41,
    characterised in that
    the holding device takes the form of a gripper (110) which by means of a belt (111) rotates in synchronism with the staggered stream and clampingly retains each first sheet-like product (14) of a stack, the transport means (60) having a speed (v) which is greater than the speed v_o of the staggered stream or of the gripper (110).
46. Apparatus according to one or more of claims 28 to 45,
    characterised by
    a support plate (130) which determines the flight path of the free-falling sheet-like products (14) and, viewed in the direction of movement of the transport means (60), is disposed behind the sheet-like products (14).

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