JP7412147B2 - How to replace piles formed from sheets in feeders - Google Patents

Description

The invention relates to a method for replacing piles formed from sheets in a feeder, with the features of claim 1.

TECHNICAL FIELD AND BACKGROUND The present invention relates to the technical field of the graphics industry, in particular the scope and scope of the feeding of piles of substrate sheets to a feeder, especially during so-called ANS operation ("automatic non-stop"). This is within the scope of pile replacement at the feeder.

Printing machines that process sheets typically include a sheet feeder and a sheet delivery, each configured as a stacking device with a lift plate. A pallet, for example made of wood or plastic, is positioned in each case on the lifting plate. At the feeder there is a pile of unprinted sheets on the pallet, and at the delivery there is a pile of printed sheets. The printing press may include a feed section, for example a roller-type feed device, which makes it possible to feed the pallet towards or away from the machine. At the feeder, for example, pallets containing a pile of unprinted sheets are fed towards the feeder, and empty pallets are fed away from the feeder. During delivery, for example, a pallet containing printed sheets is sent away from the delivery, and an empty pallet is sent toward the delivery.

Printing press feeders allow for "non-stop" pile changes. For this purpose, so-called forks are moved into the grooves of the stacking pallet beneath the decreasing residual pile (or auxiliary pile). The remaining pile is supported there by forks. The empty pallet is then lowered and moved out of the feeder. A new pallet containing a new main pile is moved into the feeder and stopped. The new pile is aligned laterally, ie transversely to the longitudinal direction of the machine, from the rest position towards the remaining pile (side-to-side alignment) and moved upwards and below the remaining pile. Finally, the fork is pulled out of the pile where the remaining pile and the new main pile are brought together. This operation can be repeated many times.

DE 1099556 discloses pile storage, pile feeding to feeders, and the use of main and auxiliary piles or raising and lowering of main and auxiliary piles. This document does not disclose monitoring by sensors.

Furthermore, DE 39 22 803 A1 discloses a sensor-assisted pile change in a feeder. This document discloses a sensor that is positioned within the feeder to assist in side-to-side alignment of the main pile.

Finally, DE 10 2006 046 526 A1 discloses a pile change in which the pile at the feeder and the individualized sheets on the feeder board are monitored by sensors.

In the prior art, the disadvantage is that the corrective movements for the left-right alignment of the sheet piles in the feeder prolong the pile change time. This wastes valuable production time.

Problem The problem of the invention is therefore to provide an improved technical solution over the prior art, which makes it possible in particular to shorten the pile change time.

Solution according to the invention This problem is solved according to the invention by a method having the combination of the features of claim 1. Advantageous and therefore advantageous developments of the invention are apparent from the dependent claims, the description and the drawing. The features of the invention, developments of the invention and embodiments of the invention can also be combined with one another to form further advantageous developments of the invention.

The present invention is a method for exchanging piles formed from sheets in a feeder of a sheet processing machine, in which sheets are separated and processed from a raised auxiliary pile, and a main pile placed on a pallet is replaced by a main pile placed on a pallet. , along a horizontal feed path to a position below the auxiliary pile in the feeder, the main pile is raised and combined with the auxiliary pile to form a new main pile, and the sheets are separated from the new main pile. In the processing method, the position of the main pile relative to the pallet is determined in a first measuring position of the feed path, which is located outside the feeder, when the pallet is stationary or when it is moving; is located in the feeder at a second measuring position of the feed section, and the main pile is moved to a position below the auxiliary pile in the feeder by controlling the drive. It is characterized in that the pile is arranged centered with respect to the auxiliary pile already before being raised.

According to the invention, additional corrective movements for laterally aligning the piles in the feeder can be omitted. With the invention it is advantageously possible to shorten the pile change time and not waste valuable production time.

Instead of carrying out an additional and time-consuming corrective movement at the feeder out of the stop position, as in the prior art, the main pile is already detected outside the feeder (at rest or while moving) and is moved sideways. A directional correction is carried out when entering the feeder or a stop position within the feeder, or the main pile is detected (during movement) when entering the feeder, and a lateral correction is performed when entering the feeder Executed upon subsequent entry into or into a stop position within a feeder.

The advantages obtained are clear in a comparison of the two examples. In the prior art, a pile change at the feeder of a printing press can take approximately 110 seconds for a standard size of 70 x 100. In this case, with multiple pile changes and a given printing speed, a productivity of approximately 9800 sheets/h typically results. According to the present invention, the time for changing piles at the feeder of a printing press can be reduced to about 100 seconds for a standard size of 70x100. Moreover, this 10 second savings is added up over multiple pile changes. In this case, under the same conditions, an increased productivity of approximately 10,800 sheets/h results.

Developments of the Invention Preferred developments of the invention are characterized by a combination of one or more of the features described below.

A preferred development of the invention provides that the position of the main pile relative to the pallet is determined in a first measuring position using a first sensor, the first sensor determining the position of the pallet. It is characterized by specifying.

A preferred development of the invention provides that the position of the main pile relative to the pallet is determined in the first measuring position using a second sensor, the second sensor determining the position of the main pile relative to the pallet. It is characterized by specifying.

A preferred development of the invention provides that the main pile is moved to a position in the feeder by a predetermined distance S1 (from the measuring point), with: S1=(M1+D1+LP/2)+(M2+D2-(LP-LS) )/2) holds true. S1 may be given, for example, as a number of motor increments.

A preferred development of the invention provides that the position of the main pile relative to the pallet is determined in the second measuring position by means of a third sensor, the third sensor determining the position of the main pile relative to the pallet. It is characterized by specifying.

A preferred development of the invention provides that the main pile is moved to a position in the feeder by a predetermined distance S2 (from the measuring point), with: S2=(M3+LP/2)+(M3+D2-(LP-LS) )/2) holds true. S2 may be given, for example, as a number of motor increments.

A preferred development of the invention provides that the auxiliary pile is placed on the fork before combining the main pile with the auxiliary pile, and the fork is withdrawn from the new main pile when the main pile is combined with the auxiliary pile, The fork is advanced under a new main pile in order to form the next auxiliary pile, characterized in that the fork is prepositioned.

A preferred development of the invention is characterized in that a new measurement of the position of the pallet is carried out using a fifth sensor for pre-positioning.

DRAWINGS AND EXEMPLARY EMBODIMENTS OF THE INVENTION The invention and its preferred developments will be explained in more detail below with reference to the drawings, namely FIGS. 1 and 2, with reference to preferred exemplary embodiments. In this case, mutually corresponding features are provided with the same reference numerals.

1 shows a machine for processing sheets with a feeder when carrying out a preferred embodiment of the method according to the invention; FIG. 2 is a schematic diagram for clearly explaining calculation of distance S1 and distance S2.

FIG. 1 shows a machine 1 for processing sheets, in particular an offset printing press or an ink printing press, with a feeder 2 for the substrate sheets to be processed, when carrying out a preferred embodiment of the method according to the invention. It shows.

The feeder 2 has a stack 3 that is vertically motorically movable and thus positionable, and a fork 4 that is also vertically mechanically movable and thus positionable. The feeder itself defines an area 5 within the feeder and an area 6 outside the feeder.

The sheets 7 to be processed, in particular to be printed, form a main pile 8 (FIG. 1 shows two main piles to be processed in sequence) arranged on a pallet 9. The main pile 8 in the region 5 in the feeder 2 is located in a predetermined horizontal position 10, in particular in a rest position, from which position the pile can perform a lifting movement 13.

Above the main pile 8 in the region 5 (on the fork 4) a so-called auxiliary pile 11 is located, from which the sheets 7 are singulated and then fed through the machine in the processing direction 12, i.e. processed. Ru.

In FIG. 1, the center 14 of the auxiliary pile 11 is shown. Center 14 may coincide with the center of the machine. However, when processing especially thin substrates, the substrate sheets (e.g. sheet piles) must be placed in the feeder 2 in such a way that the leading edge of the sheet must reliably grip the side edges of the sheet, based on its standard size. If positioning is required, the center 14 may be displaced laterally with respect to the center of the machine (keyword: "eccentric printing").

According to the invention, the position 10 is located below the auxiliary pile 11 in such a way that the main pile 8 is arranged centered relative to the auxiliary pile already before the lifting (i.e. before the execution of the lifting movement 13). . That is, at position 10, the center of the main pile 8 coincides with the center of the auxiliary pile 11.

After raising the pile 8 and processing the pile 8, the stack 3 is lowered again and the empty pallet 15 is delivered out of the feeder 2.

FIG. 1 further shows a horizontal feed section 16 for feeding the pallet 9 in a (transverse) feed direction 17. The feed section includes a number of rollers 18 of a feed device 19 , which rollers 18 are driven by at least one drive 20 . The pallet 9 can be fed laterally into the feeder 2 and laterally out of the feeder. Several rollers 18 are associated with (or arranged on) the stack 3 and are vertically movable therewith.

In the prior art, the measurement position 21 is located in the region 5. The measuring position 21 includes a (fifth) sensor 22 or a stop for determining the (lateral direction 17) position of the stationary pallet 9. Furthermore, the measuring position 21 in the prior art includes a sensor 23 for determining the position (in direction 17) of the pile 8 at rest with the pallet 9. From the two positions, the position (in direction 17) of the pile 8 on the pallet 9 can be determined. In the prior art, from the rest position, an additional corrective movement 24 of the pallet with the pile is then carried out, whereby the main pile 8 is centered and located below the auxiliary pile 11. For this purpose, the position (in direction 17) of the auxiliary pile 11 is known or in particular determined/measured. However, such corrective movements require undesired production time. The present invention therefore takes a different approach and avoids such corrective movements, as explained below.

According to the invention, the first measurement position 25 is located in the area 6 outside the feeder. Optionally, the first measuring position 25 includes a first measuring device, in particular a first sensor 26, for determining the position (in the lateral direction 17) of the stationary (or passing) pallet 9. include. This measuring device can, for example, be omitted when the pallet 9 is started in position.

Measuring position 25 includes a second measuring device 27, in particular a second sensor 27, for determining the position (in direction 17) of the pile 8 that is at rest (or has passed) with the pallet. From the two positions, the position (in direction 17) of the pile 8 on the pallet 9 or the relative distance between the pallet 9 and the pile 8 can be determined. Preferably, the leading edges (located in direction 17) of pallets 8 and piles 9 are located. Alternatively, the position of the trailing edge or special markings may be detected.

According to the invention, the pallet and pile positions are determined outside the feeder, ie in area 6. Preferably, this determination takes place in the rest position present in the feed section 16. The time for determining the two positions is thus preferably present during downtime, so that valuable production time is not wasted.

According to the invention, the position or distance of the main pile relative to the pallet is determined, and the main pile is positioned below the auxiliary pile in the feeder by controlling a predetermined drive, for example drive 20. 10, so that the main pile is already centered with respect to the auxiliary pile before being raised.

It may also be envisaged that instead of two sensors 26 and 27, one common sensor 26 or 27 is provided which determines the two positions (the position of the pallet 8 and the position of the pile 9).

As an alternative to the first measuring position 25 , a second measuring position 28 may be provided in the area 5 within the feeder 2 . This second measuring position 28 includes a third measuring device 29, in particular a third sensor 29, for determining the position (in the lateral direction 17) of the pile 9 that has moved in the direction 17 with the pallet 8. Furthermore, the sensor 29 can specify the position of the pallet 8. Alternatively, two sensors may be used to determine the two locations. From the two positions, as an alternative, the position of the pile 9 on the pallet 8 or the distance between the pile 9 and the pallet 8 can be determined. In this alternative, the position of the main pile relative to the pallet is also determined, and the main pile is moved to a position below the auxiliary pile in the feeder by controlling the drive, so that the main pile is , is already centered and placed with respect to the auxiliary pile before being raised. Since the sensor 29 is in a fixed position and the pallet/pile is moving, each position determination in this alternative is preferably based on a time signal (and in this case the feed rate of the pallet or pile is not known). ).

The machine 1 furthermore has a computing device 33, which is connected via a connection 34 to the sensor and to the drive, so that the computing device can be adapted according to the invention to control the drive. and can be used.

The calculation of the distance S1 that the pallet travels with the pile to the position 10 when the measuring point is located outside the feeder (for example in the rest position) is preferably carried out according to the following formula:
S1=(M1+D1+LP/2)+(M2+D2-(LP-LS)/2).

When the measuring point is located within the feeder, the distance S2 is correspondingly calculated according to the following formula:
S2=(M3+LP/2)+(M3+D2-(LP-LS)/2).

FIG. 2 shows a schematic diagram to make the calculation of distance S1 and distance S2 easier to understand. On the axis parallel to the pallet feeding direction, the center of the auxiliary pile 11 is input as zero, and the measurement positions M1 to M3 are input. Furthermore, the pallet length LP and the pile (or sheet) length LS are illustrated.

M1 to M3 correspond to the mounting locations of the sensors. D1 to D2 may be measured values (measured distances). LP and LS are known and provided for calculation.

The machine 1 may have an optional measuring device 35, in particular a fourth sensor 35. This measuring device 35 is used to determine the position (in the lateral direction 17) of the pallet 9 or the position of the groove in the pallet 9 for introducing the fork. Furthermore, the machine 1 may have a drive 36 for moving the fork in the lateral direction 17 and thus for prepositioning. An optional measuring device 35 can be used to determine the position of the pallet 9, so that the forks can be prepositioned and placed exactly in the grooves provided for the forks in the upper surface of the pallet. enter in.

1 Machine/printing machine that processes sheets 2 (Sheet) feeder 3 Stacking board 4 Fork 5 Area inside the feeder 6 Area outside the feeder 7 Sheet 8 Main pile 9 (Main pile) pallet 10 Position inside the feeder before lifting/lowering movement 11 Auxiliary pile 12 Processing direction 13 Lifting direction/lifting movement 14 Center of auxiliary pile (in some cases, center of machine)
15 Empty pallet 16 (Horizontal) feed section 17 Feed direction/feed movement 18 Roller 19 (Roller) feed device 20 Drive device 21 Measuring position (prior art)
22 Measuring device/fifth sensor/stopper for stationary pallets 23 Measuring device/sensor for stationary piles (prior art)
24 Correction movement (prior art)
25 First measuring position outside the feeder 26 Optional measuring device/first sensor/stop for stationary pallets 27 Measuring device/second sensor for stationary piles 28 First measuring position inside the feeder 2 measuring positions 29 Measuring device/third sensor for the moving pile 30 Position of the main pile 31 Distance of the main pile with respect to the pallet 32 Sheet standard size 33 Computing device 34 Connection 35 Optional measuring device/third sensor for the pallet Fourth sensor 36 Fork drive S1 Distance S2 Distance M1 Mounting position of the first sensor M2 Mounting position of the second sensor M3 Mounting position of the third sensor D1 Distance of the pallet to the first sensor (measured value )
D2 Distance of pile to second sensor (measured value)
LP Pallet length LS Pile or sheet length

Claims (8)

A method for replacing a pile formed from sheets in a feeder of a machine processing sheets, the method comprising:
The sheets (7) are separated and processed from the raised auxiliary pile (11), and the main pile (8) placed on the pallet (9) is moved along the horizontal feed section (16) to said feeder ( 2) to a position (10) below said auxiliary pile, raising said main pile to form a new main pile together with said auxiliary pile, and separating sheets from said new main pile; In the method of processing,
The feeding section (16) determines the relative position of the main pile (8) to the pallet (9), being located outside the feeder (6) when the pallet (9) is stationary or moving. or in a second measuring position (28) of said feed section (16) located in the feeder (5) when said pallet (9) moves. identifying and moving said main pile (8) to said position (10) below said auxiliary pile (11) in said feeder by controlling a drive device (20), said main pile already being A method, characterized in that it is arranged centered with respect to said auxiliary pile before raising. Identification of the relative position of the main pile (8) with respect to the pallet (9) is performed at the first measurement position (25) using a first sensor (26), the first sensor comprising: 2. The method of claim 1, further comprising locating the pallet. The relative position of the main pile (8) with respect to the pallet (9) is determined at the first measurement position (25) using a second sensor (27), the second sensor comprising: 3. The method of claim 2, further comprising locating the main pile. moving the main pile (8) from the first measurement position (25) to the position (10) in the feeder (2) by a predetermined distance S1, at which time:
S1=(M1+D1+LP/2)+(M2+D2-(LP-LS)/2)
4. The method according to claim 3, wherein: Identification of the relative position of the main pile (8) with respect to the pallet (9) is carried out at a second measuring position (28) using a third sensor (29), the third sensor 2. Method according to claim 1, characterized in that the main pile is located. moving the main pile (8) from the second measurement position (28) to the position in the feeder (2) by a predetermined distance S2, with:
S2=(M3+LP/2)+(M3+D2-(LP-LS)/2)
6. The method according to claim 5, wherein: Before combining the main pile (8) with the auxiliary pile, the auxiliary pile (11) is placed on the fork (4), and when the main pile is combined with the auxiliary pile, the fork is placed on the new main pile. Claims 1 to 6, characterized in that the fork is moved under the new main pile in order to form the next auxiliary pile, the fork being prepositioned. The method according to any one of the above. 8. Method according to claim 7, characterized in that a new measurement of the position of the pallet (9) is taken with a fourth sensor ( 35 ) for pre-positioning the forks .