DE19516437B4 - Method for optimizing the operating performance of a folding machine - Google Patents

Abstract

Method for optimizing the operating performance of a folding machine with a sheet feeder (20) and a plurality of successive folding stations by means of a central control device (10) in which signals from sheet detectors (B1, B2, B4 to B7) are processed at different locations along the folding machine the sheet travel distance are arranged, wherein the time interval between the sheet feeder (20) supplied trigger pulses is controlled to the smallest possible value, wherein a predetermined minimum distance between two pulse edges of the sheet detectors (B2, B4, B6, B7), of which the first the trailing edge a preceding sheet at the sheet inlet (11) of a folding station and the second represents the leading edge of the subsequent sheet, wherein the first pulse edge is supplied by an arc detector (B4, B7), from the time of sheet inlet to the time of disappearance of the sheet from the folding zone a same S signal level delivers and
before the start of production a single sheet is called up as a learning sheet and passes through all folding stations, whereby from the ...

Description

The The invention relates to a method for optimizing the operating performance a folding machine with a sheet feeder and several successive Folding stations by means of a central control device, in the Signals are processed by arc detectors that are connected to different Positions of the folding machine arranged along the sheet passage are.

to Optimization of the folding performance in a folding machine with several successive folders must the arc distance between two consecutive Set bow as small as possible become. However, the arc distance is a critical size, because too small a bow gap leads to disturbances the folding operation. To such forced by disturbances shutdown of To prevent folding machine with safety, has been a relative greater Arc distance selected, the but a loss of possible Represents folding performance.

The DE 40 13 401 A1 describes a method for setting up and controlling a folding machine with an automatic set-up procedure. In this case, the length of a pattern sheet is measured by sensors in the folding machine and stored in the machine control. This value is used in the operation of the folding machine as a target arc length for monitoring and control.

The DE 43 15 095 A1 describes a method for operating a folding machine, namely setting up the machine. In this case, an arc detector is provided, which gives a shutdown signal to the folding machine drive upon detection of an incoming sheet. This means that a sheet can be decelerated, moved further at a reduced speed, and sheet guides can be precisely adjusted in the area of the folding unit.

Out the writing "German Printer", Vol. 29, No. 47/48, 16 December 1993, page W32, it is already known, the time interval between the sheet feeder supplied trigger pulses on the smallest possible Value, which is a minimum distance between two sheets equivalent.

to Optimizing the folding performance should be the transport distance between two folds as low as possible be. The minimum arc distance, however, must be so great that a folded sheet is complete has disappeared from the sheet inlet zone of a folding unit before the next Bow can enter this zone.

It If a method is to be developed that the at the folding unit required Arc distance guaranteed and the arc distance at the suction wheel automatically established.

This is provided with the features according to the claim solved.

For a pure one Pocket folding machine is to determine the shortest arc distance the Run-in situation at the first folding unit decisive. In a combination From pocket and sword folding aggregates, the running-in situation must also be considered taken into account at the first blade folder become.

The Invention goes from consideration from that for the setting of the minimum arc distance a learning process or a regulation can be used when the folding machine has a central control device has, in which signals are processed by arc detectors that on various critical points of the folding machine along the sheet pass are arranged, in particular in the region of the sheet inlet of the respective Folding units.

Farther the time interval between the trigger pulses supplied to the sheet feeder on the smallest possible Value regulated, in which a predetermined minimum distance between two Impulse edges of the bow detectors, of which the first the trailing edge a preceding sheet on the sheet inlet of a folding station and the second represents the leading edge of the following bow, not fallen below.

Under Reference to the accompanying drawings 1a to 7b will now be an embodiment of the method described.

In the 1 and 2 the sheet feeding situations at pocket and Schwertfalzaggregaten are shown.

In the central control of a digital control system ( 10 ), the entire sensors and actuators of the folding machine are linked. In addition to the general machine functions, the controller evaluates the signals from the sensors B1, B2, B3, B4, B5, B6, B7 and controls the suction cycle (Y1) and the blade stroke (Y2, Y3).

Of the Incremental encoder (B3) is mechanically directly with the folding roller drive connected. One millimeter of paper transport equals a certain number of impulses.

The sensors B1 to B7 are covered by the sheet pass and provide the signal level ON during the sheet pass and the signal level OFF during the sheet break. The sensor B1 is located in the immediate vicinity of the suction wheel. Sensor B2 is located at the sheet inlet of the Taschenfalzaggregates. Sensor B4 is located at the pocket inlet of the first folding pocket. Sensor B5 is located on the sheet outlet of the pocket folder. The sensor B5 carries the signal level ON from the time of disappearance from the folding zone. Only when B5 carries the signal level OFF, the next sheet may enter the seaming zone.

The Sensors B6 and B7 are mounted on a format adjustable holder. The holder is adjusted so that the trailing edge of the Stop of the sword folder transported folded sheet the sensor Do not cover B6 anymore. After the bow entry becomes with the falling Signal from the signal transmitter B6 triggers the swerve stroke. The sensor B7 leads vomn Timing of the bow entry until the time of disappearance from the folding zone the signal level ON. Only when the sensor B7 the Signal level OFF, may be the next Run in bow in the folding zone of the Schwertfalzwerkes.

Either At the pocket folder as well as at the knife folder, a minimum arc distance must be maintained for the folding process to work properly.

The digital control system ( 10 ) calculated by means of the waveforms of the sensors B2, B4, B5, B6, B7 and the signals of the pulse generator B3 the correct arc distance at the suction wheel. The calculation takes into account the positions of the sensors. The signal curves of the sensors B1 to B7 are in 5 for a given sheet size and fold type.

through of a learning arc, the suction timing control becomes the correct pitch preset, so that the minimum arc distance at the pocket and Blade folder is complied with. This is a percentage security surcharge added to the measured minimum distance.

The determined Saugtakteinstellung is normally during the Maintain production. Another optimization is the actual minimum distances during the current production and by a trend determination the To reduce or increase the arc distance at the suction wheel.

at Falling below the arc distance (accident) becomes a Schwerthub for the bow already under the sword prevents and the machine shut down immediately.

Farther become the determined arc lengths used for sheet flow control.

The Sensors B2 and B4 will continue to control the complete sheet inlet used in the fold pocket.

Bag inlet control

With the leading edge of the incoming sheet jumps to B2 (signal B2 jumps from off to on) becomes a counter incremented by 1 in the controller and counted down by 1 at B4. If the sheet does not enter the pocket, the count becomes greater 1. The folding machine drive is switched off immediately.

Pocket stop control

One not to the pocket stop running bow is not correct folded and leads to production disruptions. By means of the learning sheet, the path of the incoming and outgoing Arch stored and used as a reference for the signatures in production used. The advantage of pocket inlet control is that a folded sheet early is detected and the folder drive are switched off quickly can.

Claims (1)

Method for optimizing the operating performance of a folding machine with a sheet feeder ( 20 ) and a plurality of successive folding stations by means of a central control device ( 10 ), in which signals from sheet detectors (B1, B2, B4 to B7) are processed, which are arranged at different locations of the folding machine along the sheet passage, the time interval between the sheet feeder ( 20 ), wherein a predetermined minimum distance between two pulse edges of the sheet detectors (B2, B4, B6, B7), of which the first trailing edge of a preceding sheet at the sheet inlet ( 11 ), and the second represents the leading edge of the succeeding sheet, the first pulse edge being supplied by an arc detector (B4, B7) which is the same from the time of sheet feeding to the time of the sheet disappearing from the folding zone Signal level is supplied and before production start a single sheet is called as a learning sheet and passes through all folding stations, from the signals emitted by the sheet detectors determines the sheet length and the sheet feed speed of the folding machine is set to the maximum value, in which neither a predetermined limit of the arc -Speed, yet a predetermined limit of the resulting arc length, arc distance and sheet speed speed of the sheet feeder sequence is exceeded, wherein above a certain value of the sheet length, the predetermined limit of the sheet passing speed is higher than below the determined value of the sheet length.