FR2538761A1 - METHOD AND DEVICE FOR CONTROLLING PRINTING SURFACE PORTIONS OF A MODEL PLATE OF PRINTING MACHINE - Google Patents

Abstract

PROCESS AND DEVICE FOR CONTROL OF THE PRINTER SURFACE PORTIONS OF A MODEL PRINTING MACHINE PLATE. CHARACTERIZED IN THAT ALL PROBING FIELDS ARRANGED ON A PROFILE FIXING RAIL 8, BEFORE THEIR MOVEMENT TO THE PRINTING AREA, BY MEANS OF CALIBRATION STANDARDS 3, 4 ARRANGED TRANSVERSALLY TO THE DIRECTION OF TRAVEL AND THE MEASUREMENT VALUES ARE STORED IN A CALCULATOR AND INTEGRATED TO FORM THE TOTAL VALUE. THE INVENTION RELATES TO THE CONTROL OF PRINTING MACHINES.

Description

Method and Device for Controlling Surface Portions

  The present invention relates to a method and a device for determining the printing surface portions of a stamped pattern plate or the like, outside or inside a machine. print at

  incident light means or by transparency.

  DE 30 29 273 discloses a device

  for measuring the printing area of a printing plate

  off-set, in which a straight-line photoelectric detection installation is used

  for optical probing and determination of the

  and non-printing surfaces of a plate of

  pressure with calibration marks, The detection and the exploitation of the field of the image to be printed are performed by a processing unit with a processor.

  calibrating and the printed area is deter-

  The disadvantage of this device lies in the fact that, for the measurement of the range of the image to be printed, it is necessary to provide an expensive photoelectric detection device and that, by the use of two linear light sources 9 arranged parallel to each other, the measurement error due to thermal deformation although reduced, is not completely eliminated, 2. The present invention aims to propose

  a method and a device for determining the

  printers surfaces, with a less expensive photoelectric detection system and with which one obtains a greater measurement accuracy. The technical problem posed by the invention consists in the realization of a method and a device

  with a smaller number of electrical

  components for the detection system are necessary and in which the thermal deformations of the model to be measured during the measurement process are eliminated. For the resolution of this problem, the model is stretched, by means of a traction force, on a curved support or plane and all the probing fields arranged on a profiled rail of fixation are calibrated simultaneously before the transport of the model towards the area to be printed, by means of calibration standards provided transversely to the transport direction The strip-shared model is explored in all the strips, first by small areas, and the measured values are stored in memory

  in a calculator and then integrated into the

set value.

  Advantageously, the exploration of the model is carried out in such a way that the initial probing in

  all the simultaneous bands in small areas,

  inside the bands as meanders.

  For special small surface probing, it is advan-

  to explore within partial bands along broad bands constituting zones

color of the model.

  For full efficiency, the method of application

  The tensile cation of the model is chosen in such a way that the model, by this tension, occupies its original position on the printing cylinder. In a form of application of the method, it is advantageously provided in the installation.

  sensing elements, arranged at a spacing

  on a fixing device, which is connected to a transport facility for producing a transverse displacement and a longitudinal displacement. The invention is explained below with the aid of an exemplary embodiment, with reference to FIG.

  schematically representing the whole of the

  during a meandering exploration of the model

to be printed.

  In this exploration process, the operation

  probing is carried out, simultaneously, simultaneously, in all

  the bands 1.1 to 1.5 of color width of the model.

  The measured values are taken by the fields of de-

  2.1 to 2.5 and are stored in memory before

  the measurement process itself, the probing fields 2.1 to 2, 5 are observed during the displacement,

  through calibration standards 39, 4 The De-

  placement is carried out by the transport facility 5

  in such a way that the profiled mounting rail posi-

  the probing fields 2.1 to 2.5, after the first measuring operation, the light emitted and transmitted in the probing direction 7, each time the following surface of the probing field size, the bands wide

  This displacement is performed at a large scale

  speed, which is produced, for example, by a pulse-controlled traction magnet, or by a motor not

step by step.

  The width of the probing fields 2.1 to 2.5 then corresponds to half the width of the bands of color zones of the model. When this measuring operation is completed, the displacement of the rail

  fastening profile 8, in the main direction of

  page, until the next line of the model The displacement of return is then of size equal to the length of the 4.-

  individual probing fields 2.1 to 2.5.

  After the measurement values have been taken and stored, the

  positioning of the probing fields 2.1 to 2.5 on the

  conde surface of magnitude of probing of the line in the slots of width of color zones of the model, and so

  The result is a probing path 9 in

  In this process, the exploration of the model requires a smaller number of feeler elements and the installation cost is reduced compared to the use of complete probing lines. The thermal deformations caused by a burn in the model, for example by a

  printing plate, and surface irregularities which

  result, distort the measurement values of the variations

  the intensity of the transmitted or returned light.

  a difference in printing domains detected by

  port-to reality Precise determination of the quantity

  necessary color is therefore not possible to achieve

  ser - -In order to make these thermal deformations, possibly without effect during the measuring operation, it is intended to stretch the model on its edges by means of a pulling force, which may consist, for example, of a rail According to the known arrangement with two light sources arranged parallel to the printing plate, which must be placed at a determined distance from the plate, the method according to the invention

  to eliminate the causes of falsification of the values of

safe.

  the device for the application of the method described is constituted as follows 4 The probing fields 2.1 to 2 ^ 1 consisting of surface diodes are mounted each upstream of an amplifier These amplifiers are connected 2538761 i 5. -

  with their outputs to a multiplex transmission unit.

  The analog values at the output of this multi-unit

  plex are converted by an analog converter

  number of digital signals, which are fed to a micro-calculator which puts these values in

  mate and who integrates them after each

  version of the direction of movement 5, the sampling procedure of the values measured by the multiplex transmission unit 2538761 i 6.-

RBVENDI C AT I ONS

  1. Method for the determination of portions

  the surface of a model's printers, by optical exploration

  that and detection of printed and non-printing surfaces, the process by which the pattern, or

  photoelectric detector installation, are posi-

  provided by means of a transport installation, and the photoelectric basic elements are sampled by means of calibration standards, characterized in that: a) the model is stretched by means of a mechanical force of traction, on a curved or planar support surface, b) all the probing fields arranged on a profiled fixing rail (8) are sampled simultaneously, before their displacement towards the printing domain,

  by means of calibration standards (3 4) arranged transversely

  the moving direction, c) the model, split into strips, is palpated

  first, in small areas, simultaneously in all

your bands,

  (d) the measured values are stored in

  in a calculator and integrated to form the

total value.

  Process according to claim 1,

  characterized in that the small area probing starting simultaneously in all the bands, is performed in

  each strip per meander-shaped course.

  3. Process according to claim 1,

  characterized in that the probing, within the partial bands, is carried out along the width bands

color areas of the model.

  4. Process according to claim 1,

  characterized in that the model is stretched on the cylinder

  printer in its original printing position.

  7.- 5. Device for the application of the method

  according to claim 1, with a detection device

  photoelectric sensor and a transport installation for moving the model or the detector system, characterized by probing elements,

  spaced apart on a fixing device in the wine.

  sensor assembly, and this support device is connected to a transport installation for producing a transverse displacement and a longitudinal displacement of the feelers