JPH0573644U - Sensitive material holding device for plate making camera - Google Patents

Abstract

(57) [Abstract] [Purpose] When the film F is electrostatically attracted to the photosensitive material drum 15, to ensure the attraction. [Structure] This device is a device provided in the recording unit 4 of a plate-making camera for holding the supplied film F, and has a dielectric film 15a on its surface and is a circulatory sensitive material drum around which the film is wound. 15, a charging device 16 that charges the surface of the photosensitive material drum 15 with electric charges, an elastic thin plate 42 that elastically presses the film on the surface of the photosensitive material drum against the surface of the photosensitive material drum 15, and the elastic material plate 42 The electrostatic brush 43 is provided on the downstream side in the circulation direction to remove electric charges on the surface of the film wound around the photosensitive material drum 15.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a sensitive material holding device for a plate making camera, and more particularly to a sensitive material holding device provided in a recording section of a plate making camera for holding a supplied sensitive material.

[0002]

[Prior Art]

 A camera for plate making is used when exposing image information of an original on a light-sensitive material such as film. For example, in a scanning type plate making camera, a photosensitive material such as a film is wound around a photosensitive material drum, and the original is scanned while facing the photosensitive material drum, and the image information of the original is printed on the photosensitive material wound on the photosensitive material drum. It is baked on.

In the case of holding the sensitive material on the sensitive material drum as described above, a vacuum suction type or a fixture type is known. Further, Japanese Patent Laid-Open No. 64-72136 discloses a method of electrostatically adsorbing a photosensitive material on a photosensitive material drum. In the system in which the photosensitive material is electrostatically attracted to the photosensitive material drum, a charging unit for charging an electrostatic charge on the surface of the photosensitive material drum is provided. The charging means electrostatically charges the surface of the photosensitive material drum, and electrostatically attracts and holds the supplied photosensitive material.

[0004]

[Problems to be solved by the device]

 In the device for holding the sensitive material by using the conventional electrostatic attraction method, the holding force is largely changed due to the change of environment. For example, when the environment of the room where the apparatus is installed is high temperature and high humidity, or when the environment is low temperature and low humidity, the electrostatic attraction force decreases and the photosensitive material is easily peeled off from the photosensitive material drum.

An object of the present invention is to reliably electrostatically attract a sensitive material to a sensitive material holding means such as a sensitive material drum even if the surrounding environment changes.

[0006]

A photosensitive material holding device according to the present invention is a device for holding a supplied photosensitive material, which is provided in a recording portion of a plate making camera, and includes a holding means and a charging means. It has a pressing means and a discharging means. The holding means has a dielectric layer on the surface and is a circulatory means around which a sensitive material is wound. The charging means is means for charging the surface of the holding means with electric charges. The pressing means is means for elastically pressing the sensitive material wound around the holding means against the surface of the holding means. The charge removing unit is arranged downstream of the pressing unit in the circulation direction of the holding unit, and is a unit for removing the electric charge on the surface of the photosensitive material wound around the holding unit.

[0007]

[Action]

 In the photosensitive material holding device according to the present invention, the photosensitive material supplied to the recording section of the plate making camera is wound around the surface of the circulating holding means. Here, the surface of the holding means is electrostatically charged by the charging means, and the photosensitive material wound around the holding means is electrostatically adsorbed.

On the other hand, the sensitive material electrostatically adsorbed by the holding means is elastically pressed against the surface of the holding means by the pressing means, and its lifting is prevented. Further, the electrostatic charge on the surface of the photosensitive material is neutralized by the static elimination unit disposed downstream of the pressing unit. For this reason, the electrostatic adsorption force due to the electrostatic charge on the surface of the holding means increases, and the sensitive material can be reliably held on the surface of the holding means.

[0009]

【Example】

 FIG. 1 is a schematic configuration diagram of a scanning type plate making camera to which an embodiment of the present invention is adopted. This scanning type plate making camera has a document holding frame 1 which is horizontally movable in the direction of arrow A, an illumination lamp 2 which is arranged above the document holding frame 1, and an image which guides reflected light from the document. An optical system 3, a recording section 4 for exposing image information of an original on a film as a light-sensitive material, a film supply section 5 for supplying a film to the recording section 4, and a discharge-processed film for discharge. It is mainly composed of a film discharge section 6 for performing the operation.

The image forming optical system 3 includes a plurality of mirrors 10, 11, 12 and an image forming lens 13. In the recording unit 4, the film F supplied from the film supply unit 5 is wound on the surface of a photosensitive material drum 15, and a charging device 16 for charging the photosensitive material drum 15 with an electrostatic charge (see FIG. 2). And a winding device 17 for winding the film F around the photosensitive material drum 15. A part of the components of the winding device 17 and the photosensitive material drum 15 constitute a photosensitive material holding device. The photosensitive material drum 15 is rotated in the direction of arrow B in FIG. 1 by a driving device (not shown).

The film supply unit 5 is arranged in the base 20 of the apparatus. Then, a roll film cassette 21 for storing the roll film F, a cutter 22 for cutting the film F fed from the cassette 21 to a predetermined length, and the cut film F is conveyed to the recording unit 4 side. And a belt conveyor 23 for transporting the film. A guide member 24 is arranged on the downstream side of the film supply section 5 in the transport direction. The guide member 24 is a member for guiding the film F conveyed by the conveyor 23 to the film winding device 17 side of the recording unit 4, and is rotatable in the direction of arrow C in FIG. The film discharge unit 6 has been conveyed by a separation roller 25 for separating the exposed film F from the photosensitive material drum 15, a film discharge belt conveyor 26 for conveying the separated film F, and a conveyor 26. It has a film recovery box 27 for storing the film F. A film pressing roller 28 for pressing the film F against the photosensitive material drum 15 is disposed on the upstream side of the separation roller 25 in the film discharging section 6 in the conveying direction.

Next, the charging device 16 will be described with reference to FIG. A support shaft 30 of the photosensitive drum 15 is rotatably supported with respect to a frame 31. The charging device 16 gives an electrostatic charge to the surface of the photosensitive material drum 15 via the support shaft 30. The charging device 16 includes a power source 32 for applying a DC voltage, a first conductive connector 33 provided at the tip of the support shaft 30, and a second conductive connector 33 fixed to the frame side and contacting the first conductive connector 33. It has a conductive connector 34 and a switch 35 provided between the second conductive connector 34 and the power supply 32. An insulating resin flange 37 is provided between the bearing 36 supporting the support shaft 30 and the frame 31.

As shown enlarged in FIG. 3, a dielectric film 15 a is coated on the surface of the photosensitive material drum 15. As shown in FIG. 4, which is a view taken along the arrow IV in FIG. 3, circumferential grooves 15b are formed in the photosensitive material drum 15 at predetermined intervals in the axial direction. When the film F is peeled off, a claw for separation (not shown) is inserted into the circumferential groove 15b. A dielectric film is also coated inside the groove 15b.

As shown in FIGS. 3 and 4, the winding device 17 is provided above the pair of transport rollers 40 for transporting the film F to the photosensitive material drum 15, and above the pair of transport rollers 40. And a pressing roller 41 that is formed. The pressing roller 41 is pressed against the surface of the photosensitive material drum 15, so that the film F guided on the photosensitive material drum 15 is surely brought into contact with the photosensitive material drum 15 and is conveyed without meandering. It is a roller.

Further, the winding device 17 has an elastic thin plate 42 and an electrostatic brush 43. Both the elastic thin plate 42 and the electrostatic brush 43 are fixed to the support frame 44. Both ends of the support frame 44 are supported by the frame 31, as shown in FIG. The elastic thin plate 42 is formed of a resin sheet material such as Mylar (trade name, manufactured by Toray Industries, Inc.). The thickness is preferably about 0.1 to 0.2 mm. The elastic thin plate 42 is continuously provided along the axial direction, and elastically presses the film F wound around the surface of the photosensitive material drum 15 against the surface of the photosensitive material drum 15. The electrostatic brush 43 is arranged so that its tip comes into contact with the surface of the film F 1 wound around the photosensitive material drum 15. The tip of the elastic thin plate 42 is arranged close to the tip of the elastic thin plate 42, and is located downstream of the photosensitive drum 15 in the rotational direction. The electrostatic brush 43 is grounded via the support frame 44 and the frame 31. Here, the electrostatic brush 43 is preferably brought into contact with the film F in a direction orthogonal to the surface of the photosensitive material drum 15. The electrostatic brush is formed by using a conductive brush made of carbon fiber such as ES cleaner (trade name of Nippon Kayaku Co., Ltd.).

Next, the operation will be described. First, a document is set in the document holding frame 1 in advance. Next, when a film mounting key (not shown) on the operation panel is pressed, the switch 35 of the charging device 16 is turned on, and the power source 32 passes through the first and second conductive connectors 33 and 34 and the support shaft 30. As a result, the surface of the photosensitive material drum 15 is charged with a positive electrostatic charge. On the other hand, the film F is sent out from the cassette 21 and cut into a predetermined length by the cutter 22. The cut film F is sent to the recording unit 4 side by the conveyor 23 and the guide member 24. The film F sent to the recording unit 4 is sent to the surface of the photosensitive material drum 15 by the transport roller 40, mounted on the photosensitive material drum 15, and then once stopped at a predetermined origin position (not shown), the film F is temporarily stopped. To do.

Next, the guide member 24 blocking the traveling path of the document holding frame 1 rolls over to open the traveling path, and the document holding frame 1 once enters the inner part of the traveling path. This entry position becomes the reference position for starting exposure. Next, the document frame 1 starts to move to the left side in FIG. 1, and at the same time, the illumination lamp 2 is turned on, and the photosensitive material drum 15 rotates in synchronization with the traveling movement of the document holding frame 1.

At this time, the film F is pressed against the surface of the photosensitive material drum 15 by the pressing roller 41, and the surface of the photosensitive material drum 15 is charged with a positive electrostatic charge. It is adsorbed on the surface of the photosensitive material drum 15. When the film F advances in the rotation direction as the photosensitive material drum 15 rotates, the elastic thin plate 42 elastically presses the surface of the photosensitive material drum 15. This prevents the film F from rising. Further, on the downstream side in the rotation direction, the tip of the electrostatic brush 43 contacts the surface of the film F. As a result, the positive electrostatic charge that has been polarized and charged on the surface of the film F is removed, and the electrostatic attraction force increases. In this way, the film F is firmly wound around the surface of the photosensitive material drum 15 and rotated.

When the document holding frame 1 moves to the initial position shown in FIG. 1, the illumination lamp 2 is turned off and the switch 35 of the charging device 16 is turned off. During this time, the exposed film F is separated from the photosensitive material drum 15 by the separation roller 25 at the leading end thereof, and is discharged to the film recovery box 27 by the conveyor 26. Thereafter, the same cycle is repeated to perform the exposure processing on the plurality of films F.

In this embodiment, the film F is electrostatically attracted to the photosensitive material drum 15, and the film F once wound around the photosensitive material drum 15 is attached to the surface of the photosensitive material drum 15 by the elastic thin plate 42. Since the electrostatic brush 43 removes the electrostatic charge on the surface of the film F to increase the electrostatic attraction force, the film F can be reliably attracted to the photosensitive material drum 15.

In particular, since the electrostatic brush 43 is arranged in the vicinity of the downstream side of the elastic thin plate 42 in the photosensitive material conveying direction, the electrostatic brush 43 prevents the electrostatic charge from being lifted up by the electrostatic thin plate 42. It is possible to prevent the film F from falling off in the state where the film F is most easily peeled off in the initial stage of adsorption. Further, the elastic thin plate 42 does not impede the stable rotation of the photosensitive material drum 15, because the load on the photosensitive material drum 15 is lighter than that of the pressing roller or the like.

Further, since the electrostatic attraction force between the film and the photosensitive material drum 15 is increased by the electrostatic brush 43, the voltage supplied to the photosensitive material drum 15 can be lowered. [Other Embodiments] In the above-described embodiments, the resin sheet material is used as the elastic thin plate. However, since the dielectric film 15a is formed on the surface of the photosensitive drum 15, the elastic thin plate 42 is made of a metal thin plate such as stainless steel. You may comprise by.

In addition, in order to facilitate the processing of the surface of the photosensitive material drum 15, it is conceivable that the dielectric film is not formed inside the groove 15b, but in this case, the elastic thin plate 42 is made of an insulating resin. It is necessary to form the sheet material. At this time, if the elastic thin plate 42 is composed of a plurality of members so as to be in contact with the photosensitive material drum 15 while avoiding the groove 15b, the elastic thin plate 42 may be composed of a metal thin plate.

Further, even when the dielectric film is not formed in the groove portion 15b, the thin plate body can be made of metal by coating the surface of the elastic thin plate 42 with a resin such as Teflon.

[0025]

[Effect of the device]

 As described above, in the present invention, the photosensitive material is electrostatically adsorbed to the photosensitive material drum, the photosensitive material is elastically pressed against the photosensitive material drum, and the electric charges on the surface of the wound sensitive material are removed. Since the means for providing is provided, the sensitive material can be reliably held by the holding means even if the surrounding environment or the like deteriorates.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a plate making camera to which an embodiment of the present invention is applied.

FIG. 2 is a configuration diagram of a charging device of the plate making camera.

FIG. 3 is a configuration diagram of a winding device of the plate making camera.

FIG. 4 is an IV-IV arrow view of FIG. 3.

[Explanation of symbols]

 15 Sensitive Material Drum 16 Charging Device 17 Winding Device 42 Elastic Thin Plate 43 Electrostatic Brush

Claims (1)

[Scope of utility model registration request] 1. A photosensitive material holding device provided in a recording section of a plate-making camera for holding a supplied photosensitive material, which has a dielectric layer on the surface thereof and is circulated around the photosensitive material. Holding means, charging means for charging the surface of the holding means with electric charge, pressing means for elastically pressing the photosensitive material wound around the holding means against the surface of the holding means, and the holding means by the pressing means. A photosensitive material holding device for a plate-making camera, which comprises a discharging means arranged on the downstream side in the circulation direction for discharging the electric charge on the surface of the photosensitive material wound around the holding means.