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Comment: Published by Scroll Versions from space EVO and version 9.0
Sv translation
languageen

In cases where it is not practical to assume that the web growth is linear across the paper, a nonlinear web growth profile can be created to capture the actual displacements from the base separation.

This topic provides nonlinear web growth profile examples for distortions occurring:

  • Across the web
  • Across and around the drum

Example 1: nonlinear web growth profile-across the web

This web growth profile example uses the same displacement measurements as in Table 1: Displacements from the yellow separation across a grid. It uses plate tower 1 for the black separation, plate tower 2 for the cyan separation, and plate tower 3 for the magenta separation.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE profile SYSTEM "WebGrowthProfile.dtd">
<profile>
<measurePosition x = "1" y = "1" unit = "mm"/>
<measureShift x = "1" y = "1" unit = "mm"/>
<plate tower="1" side="U">
<xshift x=
  "-886.8" dx= "-1.38" />
<xshift x=
  "-584.0" dx= "-.82" />
<xshift x=
  "-252.0" dx= "-.36" />
<xshift x=
  "-12.7"  dx= ".10" />
<xshift x=
  "12.7"   dx= ".13" />
<xshift x=
  "315.5"  dx= ".64" />
<xshift x=
  "584.0"  dx= ".95" />
<xshift x=
  "886.8"  dx= "1.40" />
</plate>

<plate tower="2" side="U">
<xshift x=
  "-886.8" dx= "-1.04" />
<xshift x=
  "-584.0" dx= "-.66" />
<xshift x=
  "-252.0" dx= "-.36" />
<xshift x=
  "-12.7"  dx= ".10" />
<xshift x=
  "12.7"   dx= ".10" />
<xshift x=
  "315.5"  dx= ".30" />
<xshift x=
  "584.0"  dx= ".46" />
<xshift x=
  "886.8"  dx= ".78" />
</plate>

<plate tower="3" side="U">
<xshift x=
  "-886.8" dx= "-.52" />
<xshift x=
  "-584.0" dx= "-.30" />
<xshift x= "-252.0" dx= "-.08" />
<xshift x= "-12.7"  dx= ".10" />
<xshift x= "12.7"   dx= ".08" />
<xshift x= "315.5"  dx= ".12" />
<xshift x= "584.0"  dx= ".23" />
<xshift x= "886.8"  dx= ".40" />
</plate>
</profile>

Note that the xshift element has two attributes: x, which is the horizontal distance across the web; and dx, which is the displacement from the base separation.

The profile also specifies how the measurements are spaced along the plate with the measurePosition element, and the measureShift element specifies the units used for the displacement measurements themselves.

Example 2: nonlinear web growth profile (across and around the drum)

In this example, measurements are made across the drum (on the x axis), and around the drum (on the y axis). Across the drum, measurements are made every 8 inches and displacements are measured in 1-millimeter increments:

< measurePosition x = "8" unit = "inch" />

<measureShift x = "1" unit = "mm" />

The x origin (the across-the-drum measurement) is at the centre of the plate, and so the left-hand x coordinates are negative, and the right-hand coordinates are positive. If the plate is 44" wide, and the first measurement is 2" in from the left edge, this left-most x coordinate will be (44/2 - 2) / 8 = -2.5. Because the measurements are spaced by measurePosition, they will have the x coordinates -2.5, -1.5, -0.5, 0.5, 1.5, and 2.5. The displacement, dx, is simply the measured difference between a feature position in the base separation and the "current" separation.

The y origin (the around-the-drum measurement) is at the plate's leading edge, and so the y coordinates start from 0 and are always positive, but otherwise, the concept is the same as the across–the-drum measurements. The yshift element has two attributes, y and dy, which specify the y offset and the displacement in the y direction respectively. An example web growth profile with nonlinear web growth in both the x and y directions is shown below:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE profile SYSTEM "WebGrowthProfile.dtd">

<profile>
<measurePosition x = "8" y = "2" unit = "inch" />
<measureShift x = "1" y = "1" unit = "mm" />
<plate tower="1" side="U">
<xshift x= "-2.5" dx= "-1.584" />
<xshift x= "-1.5" dx= "-.720" />
<xshift x= "-.5"  dx= "-1.544" />
<xshift x= ".5"   dx= ".288" />
<xshift x= "1.5"  dx= "1.288" />
<xshift x= "2.5"  dx= "1.578" />
<yshift y= ".5"   dy= "-3.288" />
<yshift y= "1.5"  dy= "0" />
<yshift y= "2.5"  dy= "-2.578" />
<yshift y= "3.5"  dy= "-4" />
<yshift y= "4.5"  dy= "-2" />
<yshift y= "5.5"  dy= "0" />
<yshift y= "6.5"  dy= "-2" />
<yshift y= "7.5"  dy= "0" />
</plate>
</profile>

 

Sv translation
languagefr

Lorsqu'il n'est pas réaliste de supposer un étirement linéaire de la bande à travers le papier, un profil d'étirement de la bande non linéaire peut être créé pour capturer le déplacement réel par rapport à la sélection de base.

Cette rubrique fournit des exemples d’étirement de la bande non linéaire pour les distorsions qui surviennent :

  • à travers la bande ;
  • à travers et autour du tambour.

Exemple 1 : profil d'étirement de la bande non linéaire à travers la bande

Cet exemple de profil d'étirement de la bande utilise les mêmes mesures de déplacement que dans le tableau 1 : déplacements par rapport à la sélection jaune sur une grille. Il utilise le modèle tour 1 pour la sélection noire, le modèle tour 2 pour la sélection cyan et le modèle tour 3 pour la sélection magenta.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE profile SYSTEM "WebGrowthProfile.dtd">
<profile>
<measurePosition x = "1" y = "1" unit = "mm"/>
<measureShift x = "1" y = "1" unit = "mm"/>
<plate tower="1" side="U">
<xshift x=
  "-886.8" dx= "-1.38" />
<xshift x=
  "-584.0" dx= "-.82" />
<xshift x=
  "-252.0" dx= "-.36" />
<xshift x=
  "-12.7"  dx= ".10" />
<xshift x=
  "12.7"   dx= ".13" />
<xshift x=
  "315.5"  dx= ".64" />
<xshift x=
  "584.0"  dx= ".95" />
<xshift x=
  "886.8"  dx= "1.40" />
</plate>

<plate tower="2" side="U">
<xshift x=
  "-886.8" dx= "-1.04" />
<xshift x=
  "-584.0" dx= "-.66" />
<xshift x=
  "-252.0" dx= "-.36" />
<xshift x=
  "-12.7"  dx= ".10" />
<xshift x=
  "12.7"   dx= ".10" />
<xshift x=
  "315.5"  dx= ".30" />
<xshift x=
  "584.0"  dx= ".46" />
<xshift x=
  "886.8"  dx= ".78" />
</plate>

<plate tower="3" side="U">
<xshift x=
  "-886.8" dx= "-.52" />
<xshift x=
  "-584.0" dx= "-.30" />
<xshift x= "-252.0" dx= "-.08" />
<xshift x= "-12.7"  dx= ".10" />
<xshift x= "12.7"   dx= ".08" />
<xshift x= "315.5"  dx= ".12" />
<xshift x= "584.0"  dx= ".23" />
<xshift x= "886.8"  dx= ".40" />
</plate>
</profile>

Remarquez que l'élément xshift comporte deux attributs : x, qui mesure la distance horizontale à travers la bande et dx, qui représente le déplacement par rapport à la sélection de base.

Ce profil spécifie également l'espacement des mesures le long de la plaque avec l'élément measurePosition, tandis que l'élément measureShift détermine les unités utilisées pour les mesures de déplacement proprement dites.

Exemple 2 : profil d'étirement de la bande non linéaire (à travers et autour du tambour)

Dans cet exemple, les mesures sont réalisées à travers le tambour (sur l'axe x) et autour du tambour (sur l'axe y). À travers le tambour, les mesures sont réalisées tous les 8 pouces (203 mm) et le déplacement est mesuré par incréments de 1 mm :

< measurePosition x = "8" unit = "inch" />

<measureShift x = "1" unit = "mm" />

L'origine x (mesure à travers le tambour) étant au centre de la plaque, les coordonnées x de gauche sont négatives et les coordonnées de droite positives. Si la plaque mesure 44 pouces (112 mm) de large et que la première mesure est de 2 pouces (50 mm) à compter du bord gauche, la coordonnée x la plus à gauche sera (44/2 - 2) / 8 = -2,5. Les mesures étant espacées par l'élément measurePosition, les coordonnées x sont les suivantes -2,5, -1,5, -0,5, 0,5, 1,5 et 2,5. Le décalage, dx, correspond simplement à la différence mesurée entre un emplacement particulier de la sélection de base et la sélection "actuelle".

L’origine y (mesure autour du tambour) étant sur le bord avant de la plaque, les coordonnées y commencent à 0 et sont systématiquement positives ; mis à part ce point, le concept est identique à celui utilisé pour les mesures à travers le tambour. L'élément yshift comporte deux attributs, y et dy, qui spécifient respectivement le décalage y et le déplacement en direction y. Un exemple de profil d'étirement de la bande non linéaire en directions x et y est illustré ci-dessous :

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE profile SYSTEM "WebGrowthProfile.dtd">

<profile>
<measurePosition x = "8" y = "2" unit = "inch" />
<measureShift x = "1" y = "1" unit = "mm" />
<plate tower="1" side="U">
<xshift x= "-2.5" dx= "-1.584" />
<xshift x= "-1.5" dx= "-.720" />
<xshift x= "-.5"  dx= "-1.544" />
<xshift x= ".5"   dx= ".288" />
<xshift x= "1.5"  dx= "1.288" />
<xshift x= "2.5"  dx= "1.578" />
<yshift y= ".5"   dy= "-3.288" />
<yshift y= "1.5"  dy= "0" />
<yshift y= "2.5"  dy= "-2.578" />
<yshift y= "3.5"  dy= "-4" />
<yshift y= "4.5"  dy= "-2" />
<yshift y= "5.5"  dy= "0" />
<yshift y= "6.5"  dy= "-2" />
<yshift y= "7.5"  dy= "0" />
</plate>
</profile>

 

Sv translation
languagezh

如果假设纸张横向的轮转机延伸误差为线性误差是不切实际的,则可以创建非线性轮转机延伸误差描述文件来捕获相对于基本色版的实际位移。

本主题提供了在下列方向发生的变形的非线性轮转机延伸误差描述文件示例:

  • 轮转机横向
  • 在成像鼓的横向和周向

示例 1:非线性轮转机延伸误差描述文件 - 在轮转机的横向

此轮转机延伸误差描述文件示例使用的位移测量方法与表 1 中相同:相对于黄版横移一个网格的位移量。黑版使用印版轮转色组 1,青版使用印版轮转色组 2,品红版使用印版轮转色组 3。

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE profile SYSTEM "WebGrowthProfile.dtd">
<profile>
<measurePosition x = "1" y = "1" unit = "mm"/>
<measureShift x = "1" y = "1" unit = "mm"/>
<plate tower="1" side="U">
<xshift x=
  "-886.8" dx= "-1.38" />
<xshift x=
  "-584.0" dx= "-.82" />
<xshift x=
  "-252.0" dx= "-.36" />
<xshift x=
  "-12.7"  dx= ".10" />
<xshift x=
  "12.7"   dx= ".13" />
<xshift x=
  "315.5"  dx= ".64" />
<xshift x=
  "584.0"  dx= ".95" />
<xshift x=
  "886.8"  dx= "1.40" />
</plate>

<plate tower="2" side="U">
<xshift x=
  "-886.8" dx= "-1.04" />
<xshift x=
  "-584.0" dx= "-.66" />
<xshift x=
  "-252.0" dx= "-.36" />
<xshift x=
  "-12.7"  dx= ".10" />
<xshift x=
  "12.7"   dx= ".10" />
<xshift x=
  "315.5"  dx= ".30" />
<xshift x=
  "584.0"  dx= ".46" />
<xshift x=
  "886.8"  dx= ".78" />
</plate>

<plate tower="3" side="U">
<xshift x=
  "-886.8" dx= "-.52" />
<xshift x=
  "-584.0" dx= "-.30" />
<xshift x= "-252.0" dx= "-.08" />
<xshift x= "-12.7"  dx= ".10" />
<xshift x= "12.7"   dx= ".08" />
<xshift x= "315.5"  dx= ".12" />
<xshift x= "584.0"  dx= ".23" />
<xshift x= "886.8"  dx= ".40" />
</plate>
</profile>

请注意,xshift 元素有两个属性:x 表示轮转机横向上的水平距离;dx 表示相对于基本色版的位移量。

描述文件还使用 measurePosition 元素指定了如何沿印版方向间隔测量,measureShift 元素则指定了位移测量本身所使用的单位。

示例 2:非线性轮转机延伸误差描述文件(在成像鼓的横向和周向)

在本例中,分别沿成像鼓的横向(在 x 轴上)和周向(在 y 轴上)进行测量。在成像鼓的横向,每 8 英寸测量一次,偏移以 1 毫米增量测量:

< measurePosition x = "8" unit = "inch" />

<measureShift x = "1" unit = "mm" />

x 方向的原点(沿成像鼓的横向测量)位于印版中心,因此左边的 x 坐标为负值,右边的坐标为正值。如果印版的宽度为 44",并且第一次测量值为距离左边界 2",则其最左边的 x 坐标将是 (44/2 - 2) / 8 = -2.5。因为测量是以 measurePosition 为间隔,所以测量值将具有下列 x 坐标:-2.5、-1.5、-0.5、0.5、1.5 和 2.5。位移量 dx 是在基本色版中的某个特征位置和“当前”色版之间测得的差值。

y 方向的原点(沿成像鼓的周向测量)位于印版的前缘,因此 y 坐标从 0 开始并始终为正值,但在另一方面,其概念与沿成像鼓横向测量的概念相同。yshift 元素有两个属性:y 和 dy,分别指定了 y 方向的偏移量和 y 方向的位移量。下面显示了一个 x 和 y 方向上具有非线性轮转机延伸误差的轮转机延伸误差描述文件示例:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE profile SYSTEM "WebGrowthProfile.dtd">

<profile>
<measurePosition x = "8" y = "2" unit = "inch" />
<measureShift x = "1" y = "1" unit = "mm" />
<plate tower="1" side="U">
<xshift x= "-2.5" dx= "-1.584" />
<xshift x= "-1.5" dx= "-.720" />
<xshift x= "-.5"  dx= "-1.544" />
<xshift x= ".5"   dx= ".288" />
<xshift x= "1.5"  dx= "1.288" />
<xshift x= "2.5"  dx= "1.578" />
<yshift y= ".5"   dy= "-3.288" />
<yshift y= "1.5"  dy= "0" />
<yshift y= "2.5"  dy= "-2.578" />
<yshift y= "3.5"  dy= "-4" />
<yshift y= "4.5"  dy= "-2" />
<yshift y= "5.5"  dy= "0" />
<yshift y= "6.5"  dy= "-2" />
<yshift y= "7.5"  dy= "0" />
</plate>
</profile>

 

Sv translation
languagede

In Fällen, in denen nicht angenommen werden kann, dass die Ausdehnung auf dem Papier linear ist, kann ein nicht lineares Papierausdehnungsprofil erstellt werden, um die tatsächlichen Verschiebungen vom Basisauszug zu erfassen.

Dieses Thema enthält nicht lineare Beispiel-Ausdehnungsprofile für folgende Verzerrungstypen:

  • In Bahnrichtung
  • In Achsen- und Umfangsrichtung der Trommel

Beispiel 1: Nicht lineares Papierausdehnungsprofil – in Bahnrichtung

Dieses Beispiel-Papierausdehnungsprofil verwendet die Verschiebungsmaße in Tabelle 1: Verschiebungen vom Gelbauszug über ein Raster. Es verwendet Plattenfarbstation 1 für den Schwarzauszug, Plattenfarbstation 2 für den Cyanauszug und Plattenfarbstation 3 für den Magentaauszug.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE profile SYSTEM "WebGrowthProfile.dtd">
<profile>
<measurePosition x = "1" y = "1" unit = "mm"/>
<measureShift x = "1" y = "1" unit = "mm"/>
<plate tower="1" side="U">
<xshift x=
  "-886.8" dx= "-1.38" />
<xshift x=
  "-584.0" dx= "-.82" />
<xshift x=
  "-252.0" dx= "-.36" />
<xshift x=
  "-12.7"  dx= ".10" />
<xshift x=
  "12.7"   dx= ".13" />
<xshift x=
  "315.5"  dx= ".64" />
<xshift x=
  "584.0"  dx= ".95" />
<xshift x=
  "886.8"  dx= "1.40" />
</plate>

<plate tower="2" side="U">
<xshift x=
  "-886.8" dx= "-1.04" />
<xshift x=
  "-584.0" dx= "-.66" />
<xshift x=
  "-252.0" dx= "-.36" />
<xshift x=
  "-12.7"  dx= ".10" />
<xshift x=
  "12.7"   dx= ".10" />
<xshift x=
  "315.5"  dx= ".30" />
<xshift x=
  "584.0"  dx= ".46" />
<xshift x=
  "886.8"  dx= ".78" />
</plate>

<plate tower="3" side="U">
<xshift x=
  "-886.8" dx= "-.52" />
<xshift x=
  "-584.0" dx= "-.30" />
<xshift x= "-252.0" dx= "-.08" />
<xshift x= "-12.7"  dx= ".10" />
<xshift x= "12.7"   dx= ".08" />
<xshift x= "315.5"  dx= ".12" />
<xshift x= "584.0"  dx= ".23" />
<xshift x= "886.8"  dx= ".40" />
</plate>
</profile>

Beachten Sie, dass dem Element „xshift“ zwei Attribute zugeordnet sind: der horizontale Abstand in Bahnrichtung („x“) und die Verschiebung vom Basisauszug („dx“).

Das Profil definiert zudem mit dem Element „measurePosition“ die Abstände, in denen die Messungen entlang der Platte erfolgen, und das Element „measureShift“ gibt die für Verschiebungsmessungen selbst verwendeten Einheiten an.

Beispiel 2: Nicht lineares Papierausdehnungsprofil – in Achsen- und Umfangsrichtung der Trommel

In diesem Beispiel werden Messungen in Achsenrichtung (auf der x-Achse) und in Umfangsrichtung (auf der y-Achse) der Trommel vorgenommen. In der Achsenrichtung der Trommel erfolgen die Messungen in Abständen von jeweils 8 Zoll, und Verschiebungen werden in Schritten von 1 mm gemessen.

< measurePosition x = "8" unit = "inch" />

<measureShift x = "1" unit = "mm" />

Der x-Nullpunkt (Messung in Achsenrichtung der Trommel) befindet sich am Mittelpunkt der Platte. Somit sind die x-Koordinaten auf der linken Seite vom Nullpunkt negativ, und die Koordinaten auf der rechten Seite sind positiv. Wenn die Platte 44 Zoll breit ist, und die erste Messung 2 Zoll vom linken Rand entfernt stattfindet, ist die äußerste linke x-Koordinate (44/2 - 2) / 8 = -2,5. Da die Messungen in den durch „measurePosition“ vorgegebenen Abständen erfolgen, lauten die x-Koordinaten -2,5, -1,5, -0,5, 0,5, 1,5 und 2,5. Die Verschiebung dx wird einfach anhand der Differenz zwischen einer Elementposition im Basisauszug und dem „aktuellen“ Auszug gemessen.

Der y-Nullpunkt (Messung in Umfangsrichtung der Trommel) befindet sich an der Vorderkante der Platte. Die y-Koordinaten beginnen somit bei 0 und sind immer positiv. Ansonsten ist das Prinzip mit dem der Messungen in Achsenrichtung der Trommel identisch. Dem Element „yshift“ sind zwei Attribute zugeordnet: „y“ für den y-Versatz und „dy“ für die Verschiebung in y-Richtung. Ein Beispiel-Ausdehnungsprofil mit nicht linearer Ausdehnung in x- und y-Richtung sehen Sie im Folgenden:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE profile SYSTEM "WebGrowthProfile.dtd">

<profile>
<measurePosition x = "8" y = "2" unit = "inch" />
<measureShift x = "1" y = "1" unit = "mm" />
<plate tower="1" side="U">
<xshift x= "-2.5" dx= "-1.584" />
<xshift x= "-1.5" dx= "-.720" />
<xshift x= "-.5"  dx= "-1.544" />
<xshift x= ".5"   dx= ".288" />
<xshift x= "1.5"  dx= "1.288" />
<xshift x= "2.5"  dx= "1.578" />
<yshift y= ".5"   dy= "-3.288" />
<yshift y= "1.5"  dy= "0" />
<yshift y= "2.5"  dy= "-2.578" />
<yshift y= "3.5"  dy= "-4" />
<yshift y= "4.5"  dy= "-2" />
<yshift y= "5.5"  dy= "0" />
<yshift y= "6.5"  dy= "-2" />
<yshift y= "7.5"  dy= "0" />
</plate>
</profile>

 

Sv translation
languageit

Nei casi in cui non conviene ritenere che l'espansione della bobina sia lineare sulla parte trasversale della carta, è possibile creare un profilo di espansione della bobina non lineare per gli spostamenti effettivi dalla selezione di base.

Il presente argomento riporta degli esempi di profili di espansione della bobina non lineare per le distorsioni che si verificano:

  • trasversalmente rispetto alla bobina
  • trasversalmente e attorno al tamburo

Esempio 1: profilo di espansione della bobina non lineare, trasversale rispetto alla bobina

Questo esempio di profilo di espansione della bobina utilizza le stesse misurazioni di spostamento indicate nella tabella 1: Spostamenti dalla selezione giallo trasversali alla griglia. Esso utilizza l'unità di stampa della lastra (plate tower) 1 per la selezione del nero, l'unità di stampa della lastra 2 per la selezione del ciano e l'unità di stampa della lastra 3 per la selezione del magenta.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE profile SYSTEM "WebGrowthProfile.dtd">
<profile>
<measurePosition x = "1" y = "1" unit = "mm"/>
<measureShift x = "1" y = "1" unit = "mm"/>
<plate tower="1" side="U">
<xshift x=
  "-886.8" dx= "-1.38" />
<xshift x=
  "-584.0" dx= "-.82" />
<xshift x=
  "-252.0" dx= "-.36" />
<xshift x=
  "-12.7"  dx= ".10" />
<xshift x=
  "12.7"   dx= ".13" />
<xshift x=
  "315.5"  dx= ".64" />
<xshift x=
  "584.0"  dx= ".95" />
<xshift x=
  "886.8"  dx= "1.40" />
</plate>

<plate tower="2" side="U">
<xshift x=
  "-886.8" dx= "-1.04" />
<xshift x=
  "-584.0" dx= "-.66" />
<xshift x=
  "-252.0" dx= "-.36" />
<xshift x=
  "-12.7"  dx= ".10" />
<xshift x=
  "12.7"   dx= ".10" />
<xshift x=
  "315.5"  dx= ".30" />
<xshift x=
  "584.0"  dx= ".46" />
<xshift x=
  "886.8"  dx= ".78" />
</plate>

<plate tower="3" side="U">
<xshift x=
  "-886.8" dx= "-.52" />
<xshift x=
  "-584.0" dx= "-.30" />
<xshift x= "-252.0" dx= "-.08" />
<xshift x= "-12.7"  dx= ".10" />
<xshift x= "12.7"   dx= ".08" />
<xshift x= "315.5"  dx= ".12" />
<xshift x= "584.0"  dx= ".23" />
<xshift x= "886.8"  dx= ".40" />
</plate>
</profile>

Si noti che l'elemento xshift presenta due attributi: x, che rappresenta la distanza orizzontale trasversalmente alla bobina e dx che rappresenta lo spostamento dalla selezione di base.

Il profilo specifica inoltre come vengono misurati gli spazi lungo la lastra con l'elemento measurePosition e l'elemento measureShift specifica le unità utilizzate per le misurare gli spostamenti.

Esempio 2: profilo di espansione della bobina non lineare, trasversalmente e attorno al tamburo

In questo esempio le misurazioni vengono effettuate trasversalmente (sull'asse x) e attorno (sull'asse y) al tamburo. Trasversalmente al tamburo, le misurazioni vengono effettuate ogni 8 pollici e gli spostamenti vengono misurati in incrementi di 1 mm:

< measurePosition x = "8" unit = "inch" />

<measureShift x = "1" unit = "mm" />

L'origine x (la misurazione trasversale al tamburo) si trova al centro della lastra, quindi le coordinate x a sinistra sono negative e quelle a destra sono positive. Se la lastra è larga 44 e la prima misurazione è di 2 verso l'interno rispetto al bordo sinistro, la coordinata x più a sinistra sarà (44/2 - 2) / 8 = -2,5. Poiché le misurazioni sono intervallate da measurePosition, esse presenteranno le coordinate x -2,5; -1,5; -0,5; 0,5; 1,5 e 2,5. Lo spostamento dx corrisponde semplicemente alla differenza misurata tra una posizione caratteristica nella selezione di base e la selezione "corrente".

L'origine y (la misurazione attorno al tamburo) viene effettuata sul bordo anteriore della lastra, quindi le coordinate y iniziano da 0 e sono sempre positive, ma a parte ciò, il concetto è lo stesso delle misurazioni trasversali al tamburo. L'elemento yshift presenta due attributi, y e dy, che specificano rispettivamente l'offset y e lo spostamento nella direzione y. Di seguito è riportato un esempio di profilo di espansione della bobina non lineare in entrambe le direzioni x e y:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE profile SYSTEM "WebGrowthProfile.dtd">

<profile>
<measurePosition x = "8" y = "2" unit = "inch" />
<measureShift x = "1" y = "1" unit = "mm" />
<plate tower="1" side="U">
<xshift x= "-2.5" dx= "-1.584" />
<xshift x= "-1.5" dx= "-.720" />
<xshift x= "-.5"  dx= "-1.544" />
<xshift x= ".5"   dx= ".288" />
<xshift x= "1.5"  dx= "1.288" />
<xshift x= "2.5"  dx= "1.578" />
<yshift y= ".5"   dy= "-3.288" />
<yshift y= "1.5"  dy= "0" />
<yshift y= "2.5"  dy= "-2.578" />
<yshift y= "3.5"  dy= "-4" />
<yshift y= "4.5"  dy= "-2" />
<yshift y= "5.5"  dy= "0" />
<yshift y= "6.5"  dy= "-2" />
<yshift y= "7.5"  dy= "0" />
</plate>
</profile>

 

Sv translation
languagees

En lo casos en los que suponer que la dilatación del papel es lineal en todo el papel no resulte práctico, puede crearse un perfil de dilatación del papel no lineal para capturar los desplazamientos reales con respecto a la separación base.

Este tema ofrece ejemplos de perfiles de dilatación del papel no lineal para distorsiones que tienen lugar:

  • A lo ancho de la bobina
  • A lo ancho y en torno al tambor

Ejemplo 1: perfil de dilatación del papel no lineal a lo ancho de la bobina

Este ejemplo de perfil de dilatación del papel utiliza las mismas medidas de desplazamiento incluidas en la Tabla 1: Desplazamientos a partir de la separación amarilla a lo ancho de la cuadrícula. Utiliza la torre de planchas 1 para la separación de negro, la torre de planchas 2 para la separación de cian y la torre de plancha 3 para la separación de magenta.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE profile SYSTEM "WebGrowthProfile.dtd">
<profile>
<measurePosition x = "1" y = "1" unit = "mm"/>
<measureShift x = "1" y = "1" unit = "mm"/>
<plate tower="1" side="U">
<xshift x=
  "-886.8" dx= "-1.38" />
<xshift x=
  "-584.0" dx= "-.82" />
<xshift x=
  "-252.0" dx= "-.36" />
<xshift x=
  "-12.7"  dx= ".10" />
<xshift x=
  "12.7"   dx= ".13" />
<xshift x=
  "315.5"  dx= ".64" />
<xshift x=
  "584.0"  dx= ".95" />
<xshift x=
  "886.8"  dx= "1.40" />
</plate>

<plate tower="2" side="U">
<xshift x=
  "-886.8" dx= "-1.04" />
<xshift x=
  "-584.0" dx= "-.66" />
<xshift x=
  "-252.0" dx= "-.36" />
<xshift x=
  "-12.7"  dx= ".10" />
<xshift x=
  "12.7"   dx= ".10" />
<xshift x=
  "315.5"  dx= ".30" />
<xshift x=
  "584.0"  dx= ".46" />
<xshift x=
  "886.8"  dx= ".78" />
</plate>

<plate tower="3" side="U">
<xshift x=
  "-886.8" dx= "-.52" />
<xshift x=
  "-584.0" dx= "-.30" />
<xshift x= "-252.0" dx= "-.08" />
<xshift x= "-12.7"  dx= ".10" />
<xshift x= "12.7"   dx= ".08" />
<xshift x= "315.5"  dx= ".12" />
<xshift x= "584.0"  dx= ".23" />
<xshift x= "886.8"  dx= ".40" />
</plate>
</profile>

Tenga en cuenta que el elemento xshift tiene dos atributos: x, que es la distancia horizontal del ancho de la bobina, y dx, que es el desplazamiento con respecto a la separación base.

El perfil especifica además el modo en que se espacian las mediciones a lo largo de la plancha mediante el elemento measurePosition; a su vez, el elemento measureShift especifica las unidades utilizadas en la medición del desplazamiento.

Ejemplo 2: perfil de dilatación del papel no lineal (a lo ancho y en torno al tambor)

En este ejemplo, las mediciones se toman a lo ancho del tambor (en el eje X) y en torno al tambor (en el eje Y). A lo ancho del tambor, se toman mediciones cada 8 pulgadas y los desplazamientos se miden en incrementos de un milímetro:

< measurePosition x = "8" unit = "inch" />

<measureShift x = "1" unit = "mm" />

El origen X (la medición a lo ancho del tambor) se encuentra en el centro de la plancha de manera que las coordenadas X de la izquierda son negativas y, las de la derecha, positivas. Si la plancha es de 44" de ancho y la primera medida es de 2" in desde la esquina izquierda, esta coordenada situada más a la izquierda será de (44/2 - 2) / 8 = -2,5. Dado que las mediciones están espaciadas por measurePosition, tendrán las coordenadas x -2,5, -1,5, -0,5, 0,5, 1,5 y 2,5. El desplazamiento, dx, es sencillamente la diferencia medida entre una posición de elemento de la separación base y la separación "actual".

El origen Y (la medición en torno al tambor) se encuentra en el borde de entrada de la plancha, de manera que las coordenadas Y empiezan desde 0 y son siempre positivas. A excepción de esta diferencia, el concepto es el mismo que el de las mediciones a lo ancho del tambor. El elemento yshift tiene dos atributos, y y dy, que especifican respectivamente el desplazamiento Y y el desplazamiento en la dirección Y. A continuación, se muestra un ejemplo de perfil de dilatación del papel con dilatación del papel no lineal tanto en la dirección X como en la dirección Y:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE profile SYSTEM "WebGrowthProfile.dtd">

<profile>
<measurePosition x = "8" y = "2" unit = "inch" />
<measureShift x = "1" y = "1" unit = "mm" />
<plate tower="1" side="U">
<xshift x= "-2.5" dx= "-1.584" />
<xshift x= "-1.5" dx= "-.720" />
<xshift x= "-.5"  dx= "-1.544" />
<xshift x= ".5"   dx= ".288" />
<xshift x= "1.5"  dx= "1.288" />
<xshift x= "2.5"  dx= "1.578" />
<yshift y= ".5"   dy= "-3.288" />
<yshift y= "1.5"  dy= "0" />
<yshift y= "2.5"  dy= "-2.578" />
<yshift y= "3.5"  dy= "-4" />
<yshift y= "4.5"  dy= "-2" />
<yshift y= "5.5"  dy= "0" />
<yshift y= "6.5"  dy= "-2" />
<yshift y= "7.5"  dy= "0" />
</plate>
</profile>