DE4131014A1 - BOW FEEDER - Google Patents

Abstract

In a sheet feeder for sheet-processing machines, in particular sheet-fed printing machines, having a pile table (2) for receiving a main pile (4), which pile table (2) can be raised and/or lowered by means of a main hoist (3), and having a nonstop device with at least one, preferably two, supporting rack(s) (13) for receiving a residual pile (4a) from the pile table (2), on which subsequently there can be received a new pile, onto which the residual pile (4a) can be deposited, which supporting racks (13) lying laterlly opposite one another being retractable and extendible by means of a rack drive device (18), can be received in grooves (5a) of the pile table (2) and can be raised and lowered by means of an auxiliary hoist (10), high functional reliability and freedom from disruption can be achieved in that there are provided in the region of at least one rack bar (14) contact sensors (22, 23) one of which faces upwards and one downwards and with the aid of which the reception of the residual pile (4a) by the nonstop device and the provision of a new pile (4) below the residual pile (4a) are detectable. <IMAGE>

Description

The invention relates to a sheet feeder for bogenver working machines, especially sheet printing machines, with a liftable from a main elevator lowerable stacking table to hold a main stack and with a non-stop facility with at least one preferably two opposite one another, by means of a retractable and extendable rake drive device, in grooves of the stacking table, by means of a Auxiliary lift lifting or lowering screen for Takeover of a remaining stack from the stacking table on which finally a new stack can be recorded on which the Remaining stack is deductible.

A sheet feeder of this type is for example from the DE 39 22 803 A1 known. With this known arrangement automation of the batch change is admitted strives. The publication mentioned does not, however  Facilities for securely determining the takeover of the remaining stack by the non-stop facility or the Recognize the provision of a new batch. Lack Such devices can lead to incorrect operation and thus cause disturbances. The well-known arrangement therefore proves to be unsafe and reliable enough.

Based on this, it is therefore the task of the present the present invention, a sheet feeder of the generic type while avoiding the disadvantages of the known arrangements with simple and inexpensive means sern that high reliability and failure freedom can be achieved.

This object is achieved in that at least two in the area of at least one rake Arranged casserole sensors are provided, of which one points up and one points down and with the help which means that the rest of the stack is taken over by the non-stop establishment and provision of a new batch are detectable.

These measures are advantageous Self-control of the takeover of the remaining stack by the Non-stop facility or the reset of the according to Be provision of a new stack of still existing parts of the remaining stack on the new main stack possible where due to a high level of functional reliability and freedom from interference are reachable. For example, the main elevator, instead, with the carrying rake arrangement retracted  the auxiliary elevator by means of a the top of the stack groping button in the stroke direction is tactile when open Running contact of the upward-facing overrun sensor in the Overdrive can be driven in the lowering direction. When open running contact of the downward facing sensor with the the new stack can be made available be initiated.

The run-up sensors can advantageously be in the form of blowing nozzles be formed, which can be acted upon by blown air, de ren feed pressure can be scanned. These measures result in a highly robust, against dust and dirt sensitive arrangement. It also ensures that markings on the adjacent sheet un stay there.

Expediently, at least two rakes can each because it is an axial pocket drill that can be blown with air have a radial bore upwards or goes down below. The use of two separately charged The blowing nozzles simplify the signal reception and serve thereby increasing security and reliability. The distribution of these two, separately actable He can manufacture blow nozzles on two rakes easier.

In further training the higher-level measures can associate the non-stop facility with each screen ten, at least when extending the associated Tragre chens to the stack edge facing this Counterholders can be provided by means of a counter neck terantriebseinrichtung on or off and by means of a sequence that can be controlled by the run-up detectors circuit can be activated before the rake extension movement  are. This makes it easy to prevent that there is a Displacement of the stack side edge results. Appropriately can each counter holder a clamping device arranges through which he stuck in the retracted state is adjustable and by means of the Auflaufde tectors controllable sequential circuit before the arithmetic movement can be activated. This can be training the drive devices assigned to the counterholders simplify.

Another expedient embodiment can be in it stand that the counterhold the gap between main and bridge auxiliary stacks and with the main and Side sensors assigned to auxiliary stacks are provided, through the one adjusting device for the side stack adjustment is controllable. This ensures that when changing the stack there are no discontinuities in the area the stack side edge arise.

Further useful training and advantageous Ausge The overall measures are based on the following description of a preferred embodiment Example using the drawing in conjunction with the remaining subclaims.

The drawing shows:

Fig. 1 is a front view of the sheet feeder according to the invention partly in section,

Fig. 2 is a plan view of the arrangement according to FIG. 1,

Fig. 3 shows an example for acted upon by blown air emergence detectors in a schematic representation;

Fig. 4 shows the operating state before taking over the rest of the stack by the non-stop device in the form of a schematic partial view

Fig. 5 shows the operating state before placing the rest of the stack on the new main stack provided below in the form of a schematic partial view.

The sheet feeder on which FIGS . 1 and 2 are based sits a portal-shaped frame 1 in which a stacking table 2 which can be raised and lowered is arranged. This is suspended from a main elevator 3 indicated by lifting chains. The stacking table 2 is down to floor level and can be loaded in the lowered state with a sheet stack 4 indicated by a dashed outline. This rests on a pallet 5 , which can be rolled up onto the stacking table 2 here. For this purpose, here is provided a track 6 extending transversely to the longitudinal axis of feeder rollers, the middle portion is a mounted on the stacking table 2. 6 The upstream and downstream sections of the roller conveyor are arranged on the corridor side.

By actuating the roller conveyor section 6 a mounted on the stacking table 2 , a lateral adjustment of the stack 4 is also possible here. In the example shown, a side stop 8 adjustable by means of an assigned drive device 7 is provided, against which the stack 4 can be moved by means of the roller conveyor section 6 a. The side stop 8 is drawn here in the extended, inactive waiting position.

In the upper area of the frame 1 , a separating and conveying unit, not shown here, is provided, for example in the form of a suction head known per se, by means of which the top sheet in each case can be removed from the stack underneath and transported away. The continuously decreasing stack height is compensated for by lifting the stack support in cycles. The clocking is accomplished by a in Fig. 4 and 5 at 9 to interpreted, the stack top scanning button be accomplished.

The stack 4 received on the stacking table 2 is referred to below as the main stack. Once this is Sta pel processed to a predetermined residual amount, it is used as a residual pile 4 in a non-stop device überge ben, lower to the then empty pile board 2 and be equipped with a new main stack 4 to. During this time, the remaining stack 4 a is processed further. The laying operation must therefore not be interrupted. The populated with a new main stack 4 stacking table 2 is then raised to the extent that can be then placed still EXISTING dene rest of the remainder of the pile 4 a to the new master pack 4 and combined with this.

The above-mentioned non-stop device comprises a suspended on egg nem indicated by its lifting chains auxiliary elevator 10 , guided on a vertical guide 11 lifting platform 12 , which, as can best be seen from FIG. 2, has two frame 12 a flanking the feeder frame 1 has, which are connected to each other by a yoke 12 b extending in the region of the front side in the sheet conveying direction. On each frame 12 a is a transversely to the longitudinal axis of movable support rake 13 is added, the rake bars 14 of the FIGS . 1 and 2 zugrun lying, side waiting position in an auxiliary stack 4 a under, in Fig. 1 indicated by dashed lines working position are feasible and vice versa. The on the stacking table 2 recordable pallet 5 is for this purpose provided with the spacing of the rake bars 14 th, also transverse to the longitudinal axis of the grooves 5 a. As soon as the pallet 5 with its grooves 5 a reaches the level of the lifting platform 12 located in a lower stop position and the carrying rake 13 recorded thereon, these are inserted with their rake rods 14 into the grooves 5 a. Subsequently, the lifting platform 12 is raised further under the command of the button 9 which scans the upper edge of the auxiliary stack 4 a which is now picked up on the supporting rake 13 . The stacking table 2 thus unloaded is lowered to the floor level.

The two supporting rakes 13 are received on a respectively assigned carriage 15 which is slidably mounted with rollers 16 on longitudinal guides 17 a arranged along the front and rear spars of the associated frame 12 and can be pushed back and forth by means of an associated drive unit 18 . The drive unit 18 is simply designed here as a drag chain that can be driven by means of a geared motor. To achieve a high stability of the rake bars 14 , these are clamped with their rear end in a flexurally and torsionally rigid support 19 , which is formed from the side bearing plates of the respectively associated carriage bridging web.

After the stacking table 2 is equipped with a new main stack 4 and this is provided below the auxiliary stack 4 a, the supporting rakes 13 are withdrawn from the working position indicated by the dashed line in FIG. 1, ie extended, the remaining stack 4 a remaining on the below it, the new main stack 4 is discontinued. In order to avoid a and the upper portion of the main stack 4 during the extension of the supporting grate 13 a displacement of the remainder of the pile 4, each support 13 is assigned to rake a backstop 20th The counter brackets 20 are also received on the lifting platform 12 and can be placed on the stack side edge 13 facing the respective associated carrying rake 13 when the supporting rakes 13 are extended. The counter-holder 20 contain adjustable pressure plates on the side of the stack, which are attached to the piston rod of an associated drive device 21 forming cylinder-piston unit, since on the associated frame 12 a of the lifting platform 12 is received. The cylinder-piston assemblies forming the counter-holding device can be provided with double-acting pistons with different active areas, so that a slow movement can be carried out with double-sided application and a fast movement with single-sided application. This makes it possible to design the adjustment process in several stages by first moving forward at high speed and then slowly moving the last piece back. Likewise, the return movement can take place in an overdrive.

In order to determine the takeover of the remaining stack 4 a by the carrying rake 13 or the arrival of a new main stack 4 below the remaining stack 4 a, so that depending on this further operations can be initiated automatically who are in the area of the carrying rake 13 , as best Fig. 3 can be seen, two accumulation sensors 22 , 23 are provided, of which here the accumulation sensor 22 is arranged upwards and the accumulation sensor 23 pointing downwards. The run-up sensors 22 , 23 are designed here as air nozzles which can be acted upon and which are closed when the relevant carrying rake 13 opens onto a surface above or below it, as a result of which the pressure in the associated supply line 24 or 25 increases. This increased pressure can be used as a control signal.

To form the emergence sensors 22 , 23 forming blow nozzles here are each associated surfaces rods 14 , each with an associated supply line 24 or 25 with a compressed air source, here in the form of the compressed air network 26 , connected, axial blind bore 27 , from the a radial bore 28 goes out, which opens in one case upwards and in the other case downwards. In the example shown, the two run-up sensors 22 , 23 are distributed over two computing bars 14 . These can belong to the same supporting screen 13 . However, it would also be conceivable to distribute the two run-up sensors 22 , 23 over both supporting rakes 13 . It would also be possible to accommodate both overrun sensors in the area of a single rake bar, although the embodiment shown is simpler in terms of production technology. Likewise, the compressed air supply is easier if both on-run sensors, as shown, listen to the same screen.

The pressure in the supply lines 24 , 25 is received by branching measurement lines 29 and leads to a downstream signal processing device 30 , from which the desired control functions can be performed, as indicated by the input arrows 31 .

The depth of the grooves 5 a of the pallet 5 is, as can best be seen from FIG. 4, greater than the diameter of the rake bars 14 . When the rake bars 14 are inserted into the grooves 5 a, both blow nozzles forming the run-up sensors 22 , 23 remain open. Accordingly, the same low pressure prevails in the supply lines 24 , 25 . After completion of the retraction process, as already mentioned above, the lifting platform 12 with the supporting rake 13 is clocked up under the control of the button 9 instead of the stacked table 2 . For this purpose, instead of the stacking table 2 associated main lift 3 of the lifting platform controlled by the switch 9 12 associated auxiliary elevator 10th By lifting the lifting platform 12 , the rake bars 14 of the supporting rake 13 run on the underside of the stack previously resting on the pallet 5 and now as an auxiliary stack 4 a on the supporting rake 13 , where through the upward-facing casserole sensor 22 bil end up opening blowing nozzle is closed. Accordingly, the pressure in the associated supply line 24 rises. This signal can be used as a control signal to initiate the lowering of the stacking table 2 . The associated main elevator 3 can be controlled by the signal processing device 30 so that it is lowered to Flurni veau at high speed. Of course, braking and a transition to a slower speed is possible shortly before the end position is reached.

The forming the upwardly facing overrunning sensor 22, opening out to the top nozzle is kept closed as long as the auxiliary pile 4 a is located on the support rakes 13. The downward-facing casserole sensor 23 bil dende, downward-opening blow nozzle is initially open, as shown in FIG. 5. During the captured on the support grate 13 is processed residual pile 4 a, on the lowered stacking table 2, a new master pack 4 is placed, as has been done in more detail above in. Then the stacking table 2 is raised. This can be done by hand control. The stroke movement can also be done initially in overdrive until about the position on which FIG. 5 is based is reached just below the supporting rake 13 . The last, short distance can be covered in a slow gear. The switch from overdrive to slow gear can be carried out automatically using suitable sensors.

In the FIG. 5 underlying the intermediate position, the bil Dende downwardly facing blowing nozzle overrunning sensor 23 is still open. If the main stack 4 is now raised further, its upper side runs up onto the underside of the carrying rake 13 , as a result of which the casserole sensor 23 , which points downward, is closed and opens out at the end of the blowing nozzle. Correspondingly, there is now also a pressure rise in the associated supply line 25 , which can be used as a control signal for starting the counter-holder 20 and for extending the supporting rake 13 . It is also conceivable to initiate these processes in dependence on a further condition, for example on the presence of a certain residual stack height, so that the same conditions are always present. The desired residual stack height can be sensed by means of a sensor, the output signal of which can be linked to the output signal of the downward-facing overrun sensor 23, for example by an AND gate.

To initiate the rake extension process, the counterholders 20 are first placed on the side of the stack, as already explained above. For this purpose, the associated drive devices 21 are controlled in such a way that the plate-shaped counterholders 20 run onto the respectively facing side of the stack. The counterholders 20 are then locked in this position. For this purpose, the cylinder-piston assemblies forming the drive devices 21 can each be assigned a clamping cylinder 32, which can be controlled via a sequential circuit integrated into the signal processing device 30 after activation of the drive devices 21 . The drive devices 18 assigned to the carrying rakes 13 can then be activated in the extension direction via a further sequential circuit integrated in the signal processing device 30 . The Ausfahrgeschwin speed can include several stages. As long as the rake bars reach deep into the stack, the extension speed can be selected depending on the material. At least from the point in time at which the rake bars 14 emerge from the stack, the extension movement can be continued at high speed. The associated drive devices can be easily provided with a frequency converter for this purpose.

The retainers 20 are here, as best 5 is seen from Fig., As adapted to the gap caused by the supporting grate 13 between the auxiliary stack 4a and the underlying provided main stack 4 bridge and, accordingly, both below and above the support rakes comprise 13 to exploiting Dende support surfaces with which they stack on the main stack 4 and auxiliary 4 a can start. In this way, any lateral shift of both the main can be accordingly stack 4 and the auxiliary stack 4 a stop. The counterholders 20 are of course designed in such a way that a collision with the neighboring rake bars 14 does not occur. In the exemplary embodiment shown, the counterholders 20 are provided with a drive-through recess assigned to the respective adjacent rake bar 14 . The retainers 20 are here as Fig. Makes NEN further erken 5, with the main stack 4 and the auxiliary stack 4 a side associated with sensors 33, through which an already above mentioned means for lateral stack adjustment can be controlled, agreement whereby upon Ver of Main stack 4 and auxiliary stack 4 a discontinuities in the stack side edge can be avoided.

Claims (12)

1. Sheet feeder for sheet processing machines, particularly sheet printing machines, which can be raised with a with means of a main lift (3) or laterally from lowerable stacking table (2) for receiving a main pile (4) and with a non-stop device having at least one, preferably two mutually opposite, by means of a rake drive device ( 18 ) retractable and extendable, in grooves ( 5 a) of the stacking table ( 2 ) receivable, by means of an auxiliary elevator ( 10 ) lifting or lowering screen ( 13 ) for taking over a remaining stack ( 4 a) from Stacking table ( 2 ), on which a new stack can then be accommodated, onto which the remaining stack ( 4 a) can be placed, characterized in that at least two run sensors ( 22 , 23 ) arranged in the area of at least one rake bar ( 14 ) are provided , one of which points up and one points down and with the help of which the takeover of the remaining stack ( 4 a) by the non-stop facility and the region It is possible to detect a new stack ( 4 ) underneath the rest of the stack ( 4 a). 2. Sheet feeder according to claim 1, characterized in that the emergence sensors ( 22 , 23 ) are designed as blowing nozzles, which can be struck with blowing air, whose supply-side pressure can be scanned bar. 3. Sheet feeder according to claim 2, characterized in that the blowing nozzles are each designed as an outgoing radial bore ( 28 ) arranged from an axial blind bore ( 27 ). 4. Sheet feeder according to claim 2 or 3, characterized in that the two emergence sensors ( 22 , 23 ) forming blowing nozzles on different rake bars ( 14 ), preferably the same Tragre chens ( 13 ), are arranged. 5. Sheet feeder according to any one of the preceding Ansprü surface, characterized in that the main elevator ( 3 ), instead of the retracted arrangement of the auxiliary elevator ( 10 ) by means of a scanning the stack top button ( 9 ) in the stroke direction is tactile, when contact of the Overhead sensor ( 22 ) can be activated in the rapid gear in the lowering direction. 6. Sheet feeder according to one of the preceding Ansprü surface, characterized in that at Auflaufkon tact of the downward opening sensor ( 23 ) the rake extension process can be initiated. 7. Sheet feeder according to one of the preceding claims, characterized in that the non-stop device is provided with at least one, each supporting rake ( 13 ) associated, at least when extending the supporting rake ( 13 ) to the facing stack edge adjustable counter-holder ( 20 ) which can be activated or deactivated by means of an associated drive device ( 21 ) and can be activated by means of a sequence circuit which can be controlled by the overrun sensors ( 22 , 23 ) before the computing extension movement. 8. Sheet feeder according to claim 7, characterized in that the counter-holder ( 20 ) in the retracted state by means of a clamping device ( 32 ) can be fixed, which can be activated by means of a sequential circuit controlled by the running sensors ( 22 , 23 ) before the computing extension movement. 9. Sheet feeder according to one of the preceding claims, characterized in that the counterholders ( 20 ) bridge the gap between the main and auxiliary stacks and are provided with the main and auxiliary stacks associated side sensors ( 33 ) by which an adjusting device for lateral adjustment of the stack is controllable. 10. Sheet feeder according to one of the preceding Ansprü surface, characterized in that two opposite, oppositely movable, Seitli che supporting rakes ( 13 ) are provided, which are mounted on a lifting platform ( 10 ) suspended on the lifting platform ( 12 ) on the supporting rakes ( 13 ) assigned, lateral frame ( 12 a), which are interconnected by a front yoke ( 12 b). 11. Sheet feeder according to one of the preceding claims, characterized in that the stacking table ( 2 ) is provided with a section ( 6 a) of a roller conveyor ( 6 ), which preferably has further sections arranged upstream and downstream and on which one the grooves ( 5 a) having pallet ( 5 ) is receivable. 12. Sheet feeder according to one of the preceding Ansprü surface, characterized in that the depth of the stack table grooves ( 5 a) is greater than the diameter of the support bars ( 14 ).