DE19526594A1 - Sheet magazine for printer - Google Patents

Abstract

The printer has a stack of sheets (4) on a pallet (16) and supported on a vertically moving platform (6). A sensor (19) monitors the height of the stack while a switch (8) monitors the top of the stack and activates the hoist drive, to maintain the top level of the stack. When the residual stack reduces to a set minimum a grid (11) is inserted between the stack and the pallet, by a continuous feed drive (10) to maintain the sheet feed while the platform is lowered and the empty pallet is replaced by a loaded pallet. The sheet lifter (2) has suction pick-ups (3) whose operating height is controlled by a height sensor (9) with high and low limit switches (9.2, 9.3). When the loaded stack is raised, a simple interlocked control sets the top of the residual stack into the low pick-up setting while the grid is withdrawn and the whole stack lifted into the new operating position.

Description

The invention relates to a device for controlling a a suction head, a stacking elevator, a non-stop facility and a control device containing sheet feeder in the non- Stop operation.

A non-stop sheet feeder is known (DE 41 31 014 A1) one that can be raised or lowered by means of a main elevator Stacking table to hold a main stack and with a non- Stop device with a by means of a computing drive device retractable and extendable, in the grooves of the stacking table cash, which can be raised or lowered by means of an auxiliary lift Carrier screen to take over a remaining stack from the stacking table which can then be picked up a new stack on which the Remaining stack is deductible. There are at least two in the area at least one rake rod arranged overflow sensors seen, one pointing up and one pointing down and with the help of which the takeover of the remaining stack by the Non-stop facility and the provision of a new batch are detectable below the remaining stack.

The batch movement and the computing device movement is performed by controlled by a button scanning the sheet stack height.

The disadvantage is that the non- Stop operation is available, the different batch movements only be controlled by the button and not gradually Forces are built up during the stacking process.

The object of the invention is to provide a device for Control of a sheet feeder non-stop operation with a signal technical connection of the same and a gradual forces construction at the batch assembly and when taking over the rest stacks.  

According to the invention, the object is achieved by the claims solves.

The inventive solution is described below using an embodiment Example explained approximately.

The drawings show in

Fig. 1 sheet feeder beginning non-stop operation

Fig. 2 sheet feeder end non-stop operation.

The sheet feeder 1 , according to FIGS. 1 and 2, contains a height-adjustable suction head 2 with several suction cups 3 for separating the uppermost sheet 5 of a sheet stack 4 and for transporting the same in the direction of the printing machine, not shown. The sheet feeder 1 further includes a stack receptacle 6 for receiving the sheet stack 4 , which is connected to a stack elevator 7 . The sheet stack 4 is arranged on a stack pallet te 16 .

The sheet feeder 1 is equipped with a stacking limit switch 8 arranged at the front edge of the sheet stack 4 . Furthermore, a detector stack height 19 is arranged on the leading edge of the sheet stack.

In the suction head 2 a button suction head height 9 is arranged, which determines the relative position of the suction head 2 to the sheet stack. The button Saugkopfhöhe 9 consists of a stack of sheets on the cyclically attachable Tasterfuß 9.1, one cooperating with the suction head sensor Tasterfuß 9.1 to 9.2 and a deep interacting with the suction head sensor Tasterfuß 9.1 9.3 too high. The sheet feeder 1 is permitted with a non-stop device 10 . The non-stop device 10 contains a bar rake 11 and a non-stop elevator 12 .

Arranged on the non-stop device 10 is a sensor stack pallet 13 , a sensor stack top edge 14 , a limit switch rod rake 15 and a limit switch rod rake 18. The sensor stacking pallet 13 determines whether there is a stacking pallet 16 that can be used for non-stop operation and whether the stacking pallet 13 is in a position for the retraction of the rod rack 11 .

The sensor top edge 14 determines whether the sheet stack 4 is in the vicinity of the bar rake 11 of the non-stop device 10 . The limit switch bar rake on 15 is actuated when the bar rake 11 is moved into the sheet stack 4 and the limit switch bar rake out 18 is actuated when the bar rake 11 is extended from the sheet stack 4 .

The sheet feeder 1 is equipped with a control device 17 which is connected on the output side to the height-adjustable suction head 2 , the stacking elevator 7 , the non-stop elevator 12 and the bar rake 11 . On the input side, the control device 17 is connected to the limit switch stack height 8 , the detector stack height 19 , the button suction head height 9 , the sensor stack pallet 13 , the sensor stack top edge 14 , the limit switch rod rake 15 and the limit switch rod rake 18 .

The operation of the Lö according to the invention solution.

In Fig. 1, the sheet feeder 1 is shown at the moment of transition from normal operation to non-stop operation.

This condition is characterized by that the on the Sta pelpalette Stop-A Non-is taken over device 16 sheet stack 4 located of the order by lowering of the stack holder 6 including the stack pallet 16 and removing pallet 16 to be able to enter a new stack of sheets of the stack.

In Fig. 2 of the sheet feeder 1 at the moment of transition from non-stop operation is shown in normal operation.

This state is characterized in that the rod rake 11 is extended from the sheet stack 4 and the remaining stack on the rod rake 11 is combined with the retracted gene stack 4 Bo.

In normal operation, the sheet stack 4 is kept at the working height necessary for exact sheet conveyance, taking into account the signals from the detector stack height 19 . The reduction of the sheet stack height by the removal of sheets is compensated for by cyclical lifting of the sheet stack 4 , which is initiated by the stack height detector 19 .

The exact position of the suction head 2 relative to the sheet stack 4 is checked and controlled by the button suction head 9 with the sensors suction head too deep 9.2 and suction head too high 9.3 .

Approaches the lower edge of the sheet stack 4 of the non-stop device 10 , the non-stop stack change is initiated. The sensor stack pallet 13 determines whether the stack pallet 16 is suitable for the non-stop stack change and whether the stack pallet 16 is in a position which is favorable for the retraction of the bar rake 11 .

If these requirements are met, the non-stop device 10 is moved synchronously with the sheet stack 4 upwards and the bar rake 11 of the non-stop device is retracted richly into the sheet stack. The rod rake 11 retracted state is determined by the rod rake limit switch 15 .

With the signal from the rod rake limit switch 15 , a loading mode of the non-stop device is switched on and the suction head sensor is switched too deep 9.2 to a different signal evaluation.

If the sensor suction head too deep 9.2 now generates the signal suction head upwards, the mode catch-up mode switches to normal operation (intermittent lifting of the non-stop device taking into account the signals of the button suction head height 9 ).

The stack holder 6 with the stacking pallet 16 is now lowered from, the stacking pallet 16 removed and a new sheet stack including the stacking pallet 16 retracted.

With the operating mode uninterrupted stacking stroke movement, the sheet stack 4 is moved upwards.

Reaches the top of the stack of sheets 4 the sensor Sta pel upper edge 14 is switched on by the signal of the same mode, the retrieval mode of the stack elevator 7 and the sensor suction head too low 9.2 switched to a unique signal evaluation. If the sensor now signals the suction head upwards, it is switched from the operating mode overhaul to normal operation.

The solution according to the invention ensures that an all gradual approach and a gradual build-up of strength at Sta pel changes regardless of the absolute height of the stack union and the takeover of the remaining stack takes place.

Reference list

1 sheet feeder
2 suction head
3 suction cups
4 stacks of sheets
5 top sheet
6 stacking
7 stacking elevator
8 stack height limit switches
9 suction head height buttons
9.1 Feet
9.2 Sensor suction head too deep
9.3 Sensor suction head too high
10 non-stop facility
11 stick rakes
12 non-stop elevator
13 Sensor stack pallet
14 Sensor top edge
15 Bar switch limit switch on
16 stack pallet
17 control device
18 Limit switch bar switch off
19 detector stack height

Claims (2)

1. Device for controlling the sheet feeder non-stop operation bes, the sheet feeder a suction head including a button suction head height with the detectors suction head too low and suction head too high, a continuous lifting by a Steuereinrich device in the operating modes and controllable by means of a detector stack height intermittent lifting vertically movable stack elevator and a non-stop device with a retractable bar rake and a non-stop device including bar rake vertically in synchronism with the stack elevator in the operating mode intermittent lifting movable non-stop elevator, characterized in that the non-stop elevator ( 12 ) after the end of a rod switch ( 15 ) detected retraction of the rod rack ( 11 ) and a switchover of the sensor suction head too low ( 9.2 ) to a unique different signal evaluation in a mode of hauling and the stacking elevator ( 7 ) after by a sens or stack top edge ( 14 ) detected Approaching the stack top edge of the sheet stack ( 4 ) to the bar rake ( 11 ) and a switchover of the sensor suction head too deep ( 9.2 ) thus effected to a unique different signal evaluation in the mode of haul-off operation can be controlled. 2. Device for controlling the sheet feeder according to claim 1, characterized in that a lifting step of the non-stop elevator ( 12 ) can be carried out in the mode of hauling-in operation at every cycle.