JPH05289316A - Image transfer device - Google Patents

Abstract

PURPOSE:To facilitate mounting and dismounting of a pin bar by constituting an upper side attaching device so forming a pin as the pin bar with a pin projected from the inner side of a blanket in an inclined part continuous with a partially notched part provided on an impression cylinder. CONSTITUTION:The partially notched part 9 is provided on the impression cylinder 8 and the blanket 10 wound around the surface of the impression cylinder 8 is fixed by a blanket fixing means 11. The inclined part 12 is provided between the partially notched part 9 and the surface of the impression cylinder (circumferential surface). The pin bar 13 is installed in this inclined part 12. The installation of the pin bar 13 is executed by pressing the pin bar 13 to the surface of the impression cylinder by the blanket having a hole in the position corresponding to the pin of the pin bar 13. The pin bar 13 is formed at such a height that its front end does not emerge to the outer side from the circumferential surface of the impression cylinder 8. The pin bar 13 as the upper side attaching device is fixed to the surface of the impression cylinder by the blanket, etc., in such a manner, thereby the mounting and dismounting of the pin bar 13 are facilitated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image transfer device. More specifically, the present invention relates to an image transfer device including a transfer cylinder and an impression cylinder provided with an image forming material impregnating device with improved registration accuracy and stable registration.

[0002]

2. Description of the Related Art Recently, an image-forming material having a photosensitive layer coated on one surface of a support is imagewise exposed, and then the image formed on the photosensitive layer is heated, generally at about 100 ° C., BACKGROUND ART Single-color or multi-color prepress proofs suitable for proof printing to be transferred to an image receptor such as paper have come to be produced. The image forming material comprises a support, a photosensitive layer formed on one surface of the support, and a protective film. A thin film or sheet made of a material such as cellulose acetate, polystyrene, polyvinyl chloride, or polyethylene terephthalate is used as the support and the protective film. As the image receptor, an appropriately selected printing material such as paper or film is adopted.

As an apparatus for producing the above-mentioned prepress proof, an impression cylinder having an image forming material attached thereto and a transfer cylinder having an image receiving member attached thereto are arranged such that the photosensitive layer of the image forming material and the image receiving member face each other. An apparatus has been generally proposed in which both cylinders are contact-pressed with each other to transfer the image formed on the photosensitive layer to an image receptor at a nip between the cylinders. To produce multicolored prints or prepress proofs, color originals are color separated to form imagewise exposed image-forming materials of respective colors, for example yellow, magenta, cyan and black, which are then formed in sequence. The image formed on the photosensitive layer of the material will be transferred to the image receptor.

As an attachment device for the image forming material in the impression cylinder, a pin bar has been usually used in order to facilitate the registration of each color. The pin bar has a plurality of pins installed on a plate extending in the axial direction of the impression cylinder. However, if the pin bar is installed directly on the impression cylinder, a distinct step will be created between the surface of the impression cylinder and the pin bar, and the registration accuracy will be insufficient due to uneven slack of the image forming material installed. Was often the case. Further, since it is not possible to perform printing with sufficient registration accuracy on the pin bar portion, there is also a problem that the actually printable area is reduced.

[0005]

As a device for attaching an image receptor to an impression cylinder, there has been a strong demand for development of a device capable of attaching a soft sheet-like material such as an image forming material without causing misregistration. A device satisfying such a demand has not been developed yet.

[0006]

SUMMARY OF THE INVENTION The present invention comprises an impression cylinder having an image forming material attached thereto and a transfer cylinder having an image receiving member attached thereto, and the image forming material and the image receiving member are rotated by rotating the impression cylinder and the transfer receiving cylinder. In an apparatus for transferring an image formed on a photosensitive layer of the forming material to an image receptor by introducing a sheet into the nip between the impression cylinder and the transfer cylinder, the image forming material attachment device is a top side of the image receptor. Is a device for holding the lower side and the lower side on the surface of the impression cylinder over the entire width direction, and the upper side attachment device projects the pin from the inner side of the blanket at an inclined portion continuous with a partial cutout provided in the impression cylinder. Provided is an image transfer device which is a pin bar.

The present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a schematic cross-sectional view of an image transfer apparatus including an impression cylinder for adhering an image forming material including the image forming material adhering device of the present invention and a transfer cylinder for adhering an image receptor such as paper. 2 and 3 are schematic sectional views of the image forming material impregnating device.

The structure of the image transfer device used in the present invention will be described below with reference to FIG. A partial cutout 2 is provided on the surface of the transfer cylinder 1, and a clamp including a nail 3 and a nail seat 4 which are upper side (holding side) attachment means of the image receptor is provided in the partial cutout, and a lower side ( (Grip end side) A clamp including the nail 5 and the nail seat 6 which are attachment means is installed. The claw 3 and the claw 5 are provided with a drive shaft 7 capable of driving the claw by a driving means such as manual or electric, and the claw 3 is opened and closed by the rotation of the drive shaft. Image receptor such as paper (not shown)
After being gripped by the gripper on the gripper side, the transfer cylinder is rotated in the direction of the arrow while pulling the image receptor, and then the image receiver is gripped by the clamp on the gripper side and attached to the transfer cylinder.

The structure of the impression cylinder 8 will be described with reference to FIG. The impression cylinder 8 is partially provided with a notch 9, and the blanket 10 wound around the surface of the impression cylinder 8 is fixed by the blanket fixing means 11 in the notch. An inclined portion 12 is provided between the partial cutout portion 9 and the impression cylinder surface (circumferential surface), and the pin bar 13 is installed on the inclined portion. Installation of the pin bar 13
It is carried out by pressing the pin bar against the surface of the impression cylinder with a blanket having holes at positions corresponding to the pins of the pin bar. The height of the pin bar 13 is set so that its tip does not extend outside the circumferential surface of the impression cylinder 8. This is because the surface of the pin bar 13 or the transfer cylinder 1 is not damaged when the impression cylinder 8 and the transfer cylinder 1 rotate. The magnet sheet 14 is rotatably mounted in the partially cutout 9. Adhesive tape 15 is provided on the surface of the impression cylinder near the inclined portion 12 on which the pin bar 13 is provided on the impression cylinder surface and in the vicinity of another inclined portion of the partially cutout portion 9. When the magnet sheet 14 is tilted in the direction opposite to the arrow, it does not reach the adhesive tape 15 but has a width sufficient to cover the pin bar 13. Holes corresponding to the upper side pin bar 13 of the image forming material are provided, and after inserting these holes into the pin bar 13, the image forming material is suppressed by the magnet sheet 14, and then the impression cylinder 8
Is rotated in the direction of the arrow to fix the upper and lower sides of the image forming material to the surface of the impression cylinder with the adhesive tape 15.

FIG. 2 shows an installed state of the pin bar 13.
The first gauge film 16 is installed on the surface of the impression cylinder, then the elastic material 17 and the second gauge film 18 are installed, the pin bar 13 is placed thereon, and a blanket having holes corresponding to the pins of the pin bar is provided. The pin bars 13 are placed in a predetermined position by stacking them and fixing them to the surface of the impression cylinder by the blanket fixing means 11 shown in FIG. Figure 3
Shows a configuration in which a pin bar is placed directly on the surface of the impression cylinder, and a first gauge film having holes formed at positions corresponding to the pins of the pin bar, an elastic material, a second gauge film, and a blanket are sequentially laminated.

As the gauge film, a polyethylene terephthalate film is generally used, and it has a function of absorbing a thickness variation generated when a blanket is used. As the elastic material, generally, a material in which cork is used in the form of a non-woven fabric is used, and exerts an appropriate elasticity on the surface of the impression cylinder.
As the blanket, generally, a laminate of several rubber layers and cloth layers is used, and is selected in consideration of elasticity, resilience and the like.

The operation of the image forming material impregnating apparatus of the present invention will be described below. Since the pin bar is fixed to the surface of the impression cylinder with a blanket or the like, it is extremely easy to attach and detach the pin bar. Further, since no distinct step is formed between the pin bar and the surface of the impression cylinder, the image forming material can be attached to the impression cylinder with high registration accuracy.

[0013]

According to the present invention, the attachment of the pin bar,
(EN) Provided is an image transfer device which can be easily removed and can obtain a multi-color prepress proof and printed matter without causing misregistration.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of an image transfer device.

FIG. 2 is a schematic explanatory view of an image forming material impregnating device.

FIG. 3 is a schematic explanatory diagram of an image forming material impregnating device.

[Explanation of symbols]

 1 Transfer cylinder 8 Impression cylinder 12 Inclined part 13 Pin bar

Claims (2)

[Claims] 1. An impression cylinder to which an image forming material is attached and a transfer cylinder to which an image receptor is attached. The image forming material and the image receptor are rotated by the rotation of the impression cylinder and the transfer cylinder. In the apparatus for transferring the image formed on the photosensitive layer of the forming material to the image receptor by introducing it into the nip between the image forming material and the image forming material attaching device, the upper side and the lower side of the image receptor are spread over the entire width direction. It is a device for holding on the surface of the impression cylinder, wherein the upper side attachment device is a pin bar in which a pin is protruded from the inside of the blanket at an inclined portion continuous with a partial cutout provided in the impression cylinder. Image transfer device. 2. The impression cylinder has a surface layer portion in which a first gauge film, an elastic material, a second gauge film, and a blanket are laminated in this order on the surface of the impression cylinder, and the pin bar is inside the first gauge film or the blanket. 2. The image transfer device according to claim 1, wherein the pin is installed in the first position, and the pin projects through the surface layer portion outside the installation position.