GB2093606A

GB2093606A - Improvements in or relating to a method for placing thick sheets on a scanner cylinder, and apparatus for executing said method

Info

Publication number: GB2093606A
Application number: GB8108154A
Authority: GB
Original assignee: CARLSEN LITHO A S
Current assignee: CARLSEN LITHO A S
Priority date: 1981-02-19
Filing date: 1981-03-16
Publication date: 1982-09-02
Also published as: DE3204832A1; DK73681A

Abstract

A method for placing relatively thick and rigid cardboard originals on a scanner cylinder is characteristic in that the thick cardboard original is exposed to a thickness reducing process, in particular a milling, prior to placing on a scanner cylinder, forming part of a conventional electronic scanner equipment. The original 5 is held by suction in a flat plane and the cutter rotates is a plane parallel thereto. <IMAGE>

Description

SPECIFICATION Improvements in or relating to a method for placing thick sheets on a scanner cylinder, and apparatus for executing said method This invention relates to a method for placing relatively thick and rigid cardboard originals on a scanner cylinder, and to an apparatus for executing the method.

When reproducing pictures, drawings or designs that are drawn or painted on relatively thick and rigid cardboard sheets, as is often preferred by designers and artists, it has not been possible hitherto to use such original cardboard sheets when using the present, common reproduction or facsimile transmission technique, in which an original is fastened firmly to the circumferential surface of a cylinder, the cylinder and the attached original then being rotated while simultaneously an electric scanner scans the original and sends signals to a receiving unit.

Therefore, when the reproduction machine operator, or facsimile transmission machine operator, is confronted with this kind of rigid and unbendable cardboard original, he is obliged to use some form or other of photography, the original picture, drawing or design being transferred to a film or paper which is sufficiently yielding to be fastened on the scanner cylinder.

Apart from the fact that such copying inevitably involves the risk of an inaccurate evential reproduction of the original picture, drawing or design this extra copying is obviously an operational step that means an increase of cost.

The object of this invention is to provide a method whereby it is possible to use even very rigid and thick cardboard sheets in connection with the scannertechnique mentioned above enabling an operatorto fix an original that has been prepared on thick cardboard easily on to a scanner cylinder, without the requirement for any form of copying of the original prior to the electronic scanning.

According to this invention there is provided a method for placing a relatively thick and rigid original on a scanner cylinder, comprising the steps of reducing the thickness of the relatively thick and rigid sheet prior to placing it on the scanner cylinder.

By this simple measure, that need not spoil the original picture, drawing or design it is possible to reduce the thickness of the cardboard sheet to a degree such that the sheet can then be fixed firmly on the scanner cylinder without wrinkling or breaking.

In a method according to the invention and preferred in practice, the thickness-reducing operation is performed by using a milling machine in which the cardboard original is placed with the picture, drawing or design facing a suction plane, by means of which the original is held in position during the milling process.

In this way it is possible to use milling machines known per se, of the type, for example, known from the Germn Patent Specification No. 1,038,567. By using a known milling machine of this kind it is possible to mill down the cardboard original to a thickness such that it can easily be placed around the scanner cylinder without the risk of parts of the picture, drawing or design being cut away.

A further object of the invention is to provide an apparatus for use when executing said method.

Thus, according to another aspect of this invention there is provided a milling machine for carrying out the above described method in which a milling cutter is arranged to rotate in a horizontal plane over a suction plane of the milling machine, on which plane the original is held by suction during the milling, wherein the milling cutter has a diamond cutting edge and a porous paper layer is placed between the suction surface and the original.

In utilising such an apparatus a cardboard original can be very securely held without wrinkling, as the porous layer ensures an even distribution over the whole area of the original of the scution power stemming from the vacuum. The use of a diamond cutting edge results in a completely clean milling of the cardboard material.

In order that the invention may be more readily understood, and so that further features thereof may be appreciated, the invention will now be described by way of example with reference to the accompanying drawing, which is a perspective view of part of an apparatus according to the invention, when in use.

As shown on the drawing, a thick cardboard original is placed on an air-permeable or porous paper layer 4 which again is placed on a milling table 1 provided with intersecting channels 3. In the embodiment shown on the drawing, a perforated metal plate 6 is furthermore placed between the porous paper layer 4 and the upper surface of the milling table 1.

When the original 5 is placed on the porous paper layer 4, with the picture, drawing or design on the cardboard in contact with the porous paper, a vacuum source connected with the channels is activated. As indicated on the drawing, the vacuum source is connected with the channels 3 through the tube 2. By activating the vaccuum source the cardboard original 5 is sucked evenly down against thelayer4. The processing ofthe reverse surface of the cardboard original Scan then be done by means of the milling cutter 9 shown schematically, thus reducing the thickness of the cardboard, without damaging the picture, drawing or design thereon.

The reduced thickness sheet then easily be mounted on the cylinder of a reproducing or facsimile transmission apparatus.

1. A method for placing a relatively thick and rigid original on a scanner cylinder, comprising the steps of reducing the thickness of the relatively thick and rigid sheet prior to placing it on the scanner cylinder.

2. A method according to claim 1, wherein the thickness of the surface of the cardboard original behind a picture drawing or design on the original is milled down.

3. A method according to claim 2 wherein the sheet is held on a milling machine by vacuum.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Improvements in or relating to a method for placing thick sheets on a scanner cylinder, and apparatus for executing said method This invention relates to a method for placing relatively thick and rigid cardboard originals on a scanner cylinder, and to an apparatus for executing the method. When reproducing pictures, drawings or designs that are drawn or painted on relatively thick and rigid cardboard sheets, as is often preferred by designers and artists, it has not been possible hitherto to use such original cardboard sheets when using the present, common reproduction or facsimile transmission technique, in which an original is fastened firmly to the circumferential surface of a cylinder, the cylinder and the attached original then being rotated while simultaneously an electric scanner scans the original and sends signals to a receiving unit. Therefore, when the reproduction machine operator, or facsimile transmission machine operator, is confronted with this kind of rigid and unbendable cardboard original, he is obliged to use some form or other of photography, the original picture, drawing or design being transferred to a film or paper which is sufficiently yielding to be fastened on the scanner cylinder. Apart from the fact that such copying inevitably involves the risk of an inaccurate evential reproduction of the original picture, drawing or design this extra copying is obviously an operational step that means an increase of cost. The object of this invention is to provide a method whereby it is possible to use even very rigid and thick cardboard sheets in connection with the scannertechnique mentioned above enabling an operatorto fix an original that has been prepared on thick cardboard easily on to a scanner cylinder, without the requirement for any form of copying of the original prior to the electronic scanning. According to this invention there is provided a method for placing a relatively thick and rigid original on a scanner cylinder, comprising the steps of reducing the thickness of the relatively thick and rigid sheet prior to placing it on the scanner cylinder. By this simple measure, that need not spoil the original picture, drawing or design it is possible to reduce the thickness of the cardboard sheet to a degree such that the sheet can then be fixed firmly on the scanner cylinder without wrinkling or breaking. In a method according to the invention and preferred in practice, the thickness-reducing operation is performed by using a milling machine in which the cardboard original is placed with the picture, drawing or design facing a suction plane, by means of which the original is held in position during the milling process. In this way it is possible to use milling machines known per se, of the type, for example, known from the Germn Patent Specification No. 1,038,567. By using a known milling machine of this kind it is possible to mill down the cardboard original to a thickness such that it can easily be placed around the scanner cylinder without the risk of parts of the picture, drawing or design being cut away. A further object of the invention is to provide an apparatus for use when executing said method. Thus, according to another aspect of this invention there is provided a milling machine for carrying out the above described method in which a milling cutter is arranged to rotate in a horizontal plane over a suction plane of the milling machine, on which plane the original is held by suction during the milling, wherein the milling cutter has a diamond cutting edge and a porous paper layer is placed between the suction surface and the original. In utilising such an apparatus a cardboard original can be very securely held without wrinkling, as the porous layer ensures an even distribution over the whole area of the original of the scution power stemming from the vacuum. The use of a diamond cutting edge results in a completely clean milling of the cardboard material. In order that the invention may be more readily understood, and so that further features thereof may be appreciated, the invention will now be described by way of example with reference to the accompanying drawing, which is a perspective view of part of an apparatus according to the invention, when in use. As shown on the drawing, a thick cardboard original is placed on an air-permeable or porous paper layer 4 which again is placed on a milling table 1 provided with intersecting channels 3. In the embodiment shown on the drawing, a perforated metal plate 6 is furthermore placed between the porous paper layer 4 and the upper surface of the milling table 1. When the original 5 is placed on the porous paper layer 4, with the picture, drawing or design on the cardboard in contact with the porous paper, a vacuum source connected with the channels is activated. As indicated on the drawing, the vacuum source is connected with the channels 3 through the tube 2. By activating the vaccuum source the cardboard original 5 is sucked evenly down against thelayer4. The processing ofthe reverse surface of the cardboard original Scan then be done by means of the milling cutter 9 shown schematically, thus reducing the thickness of the cardboard, without damaging the picture, drawing or design thereon. The reduced thickness sheet then easily be mounted on the cylinder of a reproducing or facsimile transmission apparatus. CLAIMS

4. A milling machine for carrying out a method according to claim 1, in which a milling cutter is arranged to rotate in a horizontal plane over a suction plane ofthe milling machine, on which plane the original is held by suction during the milling wherein the milling cutter has a diamond cutting edge and a porous paper layer is placed between the suction surface and the original.

5. A method of placing an original on a cylinder substantially as herein described with reference to the accompanying drawings.

6. A milling machine according to claim 5 and substantially as herein described with reference to the accmpanying drawings.

7. Any novel feature or combination of features disclosed herein.