JPH0597260A - Sheaved paper feeding device - Google Patents

Abstract

PURPOSE: To provide a paper sheet feeder which can achieve high productivity by using a simple and economical means. CONSTITUTION: A suction head 14 can be transferred to its lowermost position after the treatment of a pile 3. The suction head 14 can be elevated from the lowermost position in accordance with a signal which is generated when a sensor 21 belonging to the suction head 14 runs onto the upper surface of a new pile 3 when the new pile 3 is elevated. At that time, the lifting speeds of lifting devices 31, 32 and 33 belonging to the suction head 14 correspond at least to the lifting speed of a pulling-up device 4 belonging to a pile loading table 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding device provided with a pile mounting table movable by using a pulling device and a suction head acting on the pile mounting table from above. , It is possible to adjust the movement in the transport direction in relation to the sheet format by means of a sliding device and in the vertical direction by means of a lifting device, in which case the pulling device assigned to the pile platform is the front pile. A lifting device, which is controllable in relation to the signal emitted by the sensor for detecting the upper edge and which is associated with the suction head, is preferably received by the suction head and detects the upper edge of the rear pile. Of the type which is controllable in relation to the signal emitted from the.

[0002]

PRIOR ART German Patent Application Publication No. 362
In the known sheet feeder according to 2693, the suction head is brought to its uppermost position after the pile has been processed, i.e. during the lowering stroke of the empty pile carrier. Then, in this standby position, the suction head remains until the upper edge of the new pile reaches the working height. Only after that, the suction head is lowered, and at this time, the suction head moves close to an appropriate position by using a sensor for detecting the rear upper edge of the pile. This operation requires a relatively long adjustment time,
Therefore, the achievable productivity is adversely affected.

[0003]

SUMMARY OF THE INVENTION The object of the present invention is therefore to improve a sheet feeder of the type mentioned at the beginning such that high productivity can be achieved using simple and inexpensive means. It is to be.

[0004]

In order to solve this problem, in the structure of the present invention, the suction head is movable to the lowest position after the pile is processed, and the suction head moves to the lowest position during the rising stroke of a new pile. It is possible to lift from a lower position in relation to the signal formed when the associated sensor is mounted on the pile upper surface, in which case the lifting speed of the lifting device associated with the suction head is at least as high as the pile platform. It corresponds to the ascending speed of the attached pulling device.

[0005]

The arrangement according to the invention makes it possible to bring the suction head substantially together with the pile into its working position. In this case, the adjustment time between the arrival of the pile in the working position and the arrival of the suction head in the working position can be saved in an advantageous manner. Moreover, unacceptable collisions are eliminated on the basis of the mutually coordinated lifting speeds of the pile and suction head. Therefore, the sheet feeding device configured as in the invention can ensure high productivity, operational comfort, failure prevention and operational reliability in an advantageous manner.

In another advantageous embodiment of the invention, the lifting speed of the lifting device associated with the suction head is greater than that of the lifting device associated with the pile mount.
It is set to be 0 to 20% larger. In this way, a stepwise upward movement of the suction head is produced in an advantageous manner, which makes it possible to achieve particularly high operational reliability and failure protection.

In a further advantageous embodiment of the invention, the sensor for detecting the rear upper edge of the pile is constructed as a press foot which is received by the suction head and moves up and down.
The press foot is movable to its lowest position when the suction head is stopped. With this configuration, the sensor assigned to the suction head is guaranteed to occupy an appropriate position for detecting the upper edge of the pile at the standby position of the suction head.

In still another configuration of the present invention, a sequence circuit is provided, and the sequence circuit is used to perform vacuum load on the lifting sucker of the suction head and supply of pressurized air to the blow nozzle so that the pile and the suction head are provided. It is configured to be operable only after the working position is obtained. In this way, by automatically connecting and connecting vacuum and blowing air at the proper time,
It is possible to suppress troubles in driving and eliminate the possibility of erroneous operation by hand.

It is also advantageous if the lifting sucker of the suction head can be moved to its lowest position when the suction head is stopped. With this configuration, the sucker of the suction head can surely occupy the starting position at the standby position of the suction head, and can reliably catch the sheet at the time of vacuum load at the starting position. This makes it possible to eliminate the waiting time more advantageously in combination with the sequence circuit.

[0010]

Embodiments of the present invention will now be described with reference to the drawings.

The sheet feeding device shown in the drawings comprises a portal frame 1 in which a pile platform 2 is guided so as to be vertically movable. A paper feed pile 3 can be arranged on the pile platform 2 and the paper feed piles are stacked one on top of the other and are fed using a paper sheet feeder of a sheet processing machine, for example a printing machine. It is made up of a number of sheets of paper. The pile mounting table 2 is formed by a lifting chain and has a drive motor 5
It is suspended by a pulling device 4 equipped with. Paper pile 3
The front edge stopper 6 formed by a vertical strip is in contact with the front surface of the. The other pile side edges and trailing edges are open.

In the working position, the uppermost sheet must be able to advance past the leading edge stopper 6 each time. In order to adjust this working position, there is provided a sensor 8 which is arranged at the desired height and which is assigned to the upper edge 7 of the front pile, by means of which the motor 5 is used to drive the feed pile 3 Can be operated until is located at the desired height. For this purpose, the signal produced by the sensor 8 is processed by means of the control device 9 into a suitable input signal for the motor 5 (from the sensor 8 to the control device 9 and from this control device to the motor 5). Signal conductor 10,1
1). The control device 9 is preferably configured in such a way that all functions of the sheet feeder can be controlled by this control device. The sensor 8 can be configured as a mechanical scanner that can cooperate with a two-point switch. In the embodiment shown, the sensor 8 is embodied as a contactless sensor, for example in the form of a reflection switch, that is to say it produces a signal which can be directly processed by the control device 9.

Since the pile mounting table 2 is lifted step by step when the pile is consumed by using the sensor 8, the front upper edge 7 of the pile is always advanced with the uppermost sheet past the front edge stopper 6. It will occupy the desired working position. When lifting a new pile, the sensor 8 also limits the upward movement. This raising movement can be carried out in two stages, ie the new pile is first brought in a quick motion to approach from the lowest position to the position just before the working position and then in a slow motion to the working position. .. To switch the motor 5 from quick to slow motion, a monitoring device 12, which is located below the working position and which in the illustrated embodiment is located in the area of the leading edge stopper 6, is activated. This monitoring device has a substantially photocell shape and is adapted to release the desired switching operation as soon as the paper feed pile 3 has passed (see signal conductor 13 leading to the control device 9). By detecting the pile leading edge 7 for pile height positioning, it is ensured that the leading edge 7 of the pile 3 occupies the correct height even if the pile surface is not flat.

A suction head 14 is arranged above the pile 3, and this suction head is taken up by the lifting sucker 15 for lifting the uppermost sheet of the pile 3 in each case, and the lifting sucker. Drag sucker 16 for forward transport of sheets 16
And have. Then, the sheet is delivered to a conveying unit that is assigned to the sheet feeding table 17 and further guides the sheet during forward conveyance. The lifting sucker 15 and the drag sucker 16 are designed to be loaded with vacuum during their operation. For this purpose, a vacuum conduit 18 is provided which leads from a vacuum source (not shown) to the suction head 14, which vacuum conduit can be interrupted by means of a switching device 19. The suction head 14 is further provided with a press foot 21 newly mounted on the rear pile upper edge 20 at each work step. Press foot 2
In the area 1 there are provided a plurality of blow nozzles 37, which are connected via a pressure air conduit 22 which can be shut off by means of a switching device 23 to a pressure air source (not shown). There is. The switching device 19; 23, for example in the form of a switching valve, is controllable by means of the control device 9, as indicated by the signal conductors 24; 25. The vacuum load on the sucker and, in this case, the lifting sucker 15 which first operates, and the pressure air load on the blow nozzle, are in this case only when the pile 3 and the suction head 14 reach their working position.

The suction head 14 is formed by a square rail fixed to the frame of the sheet feeding device, extends parallel to the sheet conveying direction, and is oriented parallel to the pile mounting table 2. It is slidably guided along the longitudinal guide 26. During each format change, the suction head 14 is shifted so that the press foot 21 collides with the rear pile upper edge 20. For movement adjustments related to the format of the suction head 14, a threaded spindle 28, which can be driven by means of an adjusting motor 27, acts, which threaded spindle is axially supported by a longitudinal guide 26. And engages the threaded sleeve of the suction head 14 which projects laterally beyond the longitudinal guide 26. The adjusted operating position may in this case be lockable by means of a tensioning device (not shown). The adjusting motor 27 is controllable via the controller 9, as indicated by the signal line 29. The control device 9 includes an input device 30 for manually inputting a format.
May be provided. As a result, when a pile is exchanged, a new pile format is input. The operation of the drive motor 5 of the pulling device 4 is in this case only released when the suction head 14 is adjusted to the new format.

The working height of the suction head 14 is adjusted corresponding to the rear pile upper edge 20, which may be different from the front upper edge 7, as indicated by the angle α. For this purpose, the longitudinal guide 26 associated with the suction head 14 together with the associated adjusting device are threaded perpendicularly to the plane of the pile table 2 or the sheet transport plane, with the threads received in the feeder frame. Receiving on a spindle 31, these threaded spindles can be driven by their respective bevel gear transmissions. The two bevel gear transmissions are connected to one another via a shaft 32 which is parallel to the longitudinal guide, which shaft is drivable via an associated adjusting motor 33. In order to ensure the translation of the longitudinal guide 26 and thus of the suction head 14, two spindles 31 arranged at the front and rear ends of the longitudinal guide 26 and likewise drivable.
Is provided. The control of the adjusting motor 33 is related to the signal emitted by the press foot 21, which can be supplied by means of the control device 9 via the signal conductor 35 of this control device 9, as indicated by the signal conductor 34. Done. The press foot 21 essentially forms a mechanical sensor for detecting the rear pile upper edge 20. In this case, the press foot 21 may cooperate with a two-point switch (not shown), in which case a switching signal is generated below a certain position and above a certain position. These switching signals can then be processed by the control device 9 into on / off commands for the adjusting motor 33.

During the feeding operation of the pile 3, the suction head 14 uses the above-mentioned device for adjusting its height, irrespective of the position of the front pile upper edge 7, the front pile upper edge 20. Always held equidistant to the rear pile top edge 20, which may be offset from.
When the empty pile mounting table 2 is moved downward after the pile 3 is fed, the suction head 14 is also brought to the lowest position. For this purpose, the adjusting motor 33 uses the control device 9 to drive the spindle 31
The threaded bush penetrated by is contacted until it contacts the lower stopper. The press foot 21 likewise occupies a position below it. This is achieved by the suction head 14 being properly shut off by means of the control device 9 after the pile feeding operation, i.e. the press foot 21 occupies its lowest position. The same is true for the lifting sucker 15, which is desired to first come into contact with the sheet at restart. As described above, the step-wise proper shutoff of the suction head 14 using the control device 9 is
This is indicated by signal conductor 36. Of course, the lowering movement of the suction head 14 to the lower standby position does not have to be carried out at the same time as the lowering movement of the empty pile mounting table 2, but at another time, for example, with the format adjustment of the suction head 14 or a quick operation. To a slow movement and the like when switching the suction head 14 to something similar.

The suction head 14 adjusted to the new format and brought to the lowermost position has a height sensor with a press foot 21 likewise moved downwards, which is assigned to the rear pile upper edge 20. As a result, it stays in the standby position until it rides on the upper edge 20 of the rear pile. When the press foot 21 is raised in this case and the two-point switch associated with it is connected, this causes a closing connection signal for the adjusting motor 33, which results in the suction head 14 being lifted. However, this raising movement continues until the press foot 21 is moved again and the lower contact of the two-point switch cooperating with it is actuated. The control of the adjusting motor 33 for performing the ascending movement is performed by the suction head 1
It is done so that the rate of rise of 4 corresponds to the rate of rise of a new pile that is lifted with the pulling device 4 or is preferably somewhat higher than this. It is particularly advantageous in this case if there is a speed difference of 10 to 20%. With this configuration, a stepwise upward movement of the suction head 14 is generated. This speed relationship can be applied to the ascending operation during the normal paper feeding operation.

As soon as the pile reaches its working position during the lifting movement of the new pile, that is, the front upper edge 7 of the pile.
As soon as is detected by the associated height sensor 8, the lifting device 4 and thus the height adjusting device of the suction head 14 is stopped, whereby the pile 3 and the suction head 14 are stopped in their working position. As soon as this working position is obtained, the paper feeding operation can be started without further delay. For this paper feeding operation, first, the lifting sucker 15 and then the drag sucker 16 are vacuum-loaded, and blown air is supplied to the blow nozzle of the press foot 21. The loading of these vacuums and the supply of blown air are performed in relation to the working position of the suction head 14, as already mentioned above. Therefore, the controller 9 is provided with an appropriate sequence circuit.

[Brief description of drawings]

1 is a side view of a sheet feeder according to the invention in partial section.

[Explanation of symbols]

1 frame, 2 pile loading table, 3 pile,
4 pulling device, 5 drive motor, 6 leading edge stopper, 7 front pile upper edge, 8 sensor, 9 control device, 10, 11 signal lead wire, 12 monitoring device,
13 signal conductor, 14 suction head, 15
Lifting sucker, 16 Drag sucker, 17
Paper feed table, 18 vacuum conduits, 19 switching device, 20 rear upper edge of pile, 21 press foot,
22 pressure air conduit, 23 switching device, 24,
25 signal conductors, 26 longitudinal guides, 27 adjusting motors, 28 threaded spindles, 29 signal conductors, 30 input devices, 31 spindles, 33 adjusting motors, 34, 35, 36 signal conductors, 37 blow nozzles

Claims (8)

[Claims] 1. A sheet feeding device comprising a pile mounting table (2) movable by using a pulling device (4) and a suction head (14) acting on the pile mounting table from above. The suction head (14) has a sliding device (27, 2).
8) is adjustable in the transport direction in relation to the sheet format and in the vertical direction by means of lifting devices (31, 32, 33), in this case assigned to the pile platform (2). A lifting device (4) which is controllable in relation to the signal emitted by a sensor (8) which detects the upper pile upper edge (7) and which is associated with the suction head (14). 31, 32,
33) of the type in which the suction head (14) after the treatment of the pile (3) is controllable in relation to a signal emitted by a sensor (21) which detects the upper edge (20) of the rear pile. It is movable to its lowest position and is associated with the signal produced when the associated sensor (21) is riding on the pile top from its lowest position during the upstroke of the new pile (3). Can rise,
In this case, at least the lifting speed of the lifting device (31, 32, 33) assigned to the suction head (14) is the lifting device (4) assigned to the pile mounting table (2).
A sheet feeding device characterized in that it corresponds to the ascending speed of. 2. The lifting speed of the lifting device (31, 32, 33) attached to the suction head (14) is
2. The sheet feeding device according to claim 1, wherein the lifting speed of the pulling device (4) assigned to the pile mounting table (2) is set to be 10 to 20% higher. 3. A sensor for detecting the rear upper edge (20) of the pile is constructed as a press foot (21) which is received by the suction head (14) and moves up and down, and the press foot (14). 3. The sheet feeding device according to claim 1, wherein the sheet feeding device is movable to the lowest position thereof when stopped. 4. The sheet feeder according to claim 1, wherein the lifting device (31, 32, 33) assigned to the suction head is configured as a parallel moving device. .. 5. The pulling device (4) assigned to the pile mounting table (2) is appropriately adapted to the format by using the sliding device (26, 27, 28) to which the suction head (14) belongs. 5. The sheet feeding device according to claim 1, which can be released for the first time afterwards. 6. A sequence circuit is provided, by means of which the vacuum load on the lifting sucker (15) of the suction head causes a sensor (8) to detect the front upper edge (7) of the pile. 6. The sheet feeding device according to claim 1, wherein the sheet feeding device is operable only after the working position of the pile (3) detected using it has been obtained. 7. The sheet feeder according to claim 1, wherein the lifting sucker (15) is movable to its lowest position when the suction head (14) is stopped. .. 8. A sequence circuit is provided, by means of which the blown air supply to the blow nozzle (37) uses a sensor (8) for detecting the front upper edge (7) of the pile. 8. The method according to claim 1, wherein the operation is possible only after the working position of the pile (3) is detected.
The sheet feeder according to any one of items 1 to 7.