JP2509644Y2 - Sheet transfer device - Google Patents

Description

[Detailed Description of the Invention] Purpose of the Invention: (Industrial field of application) This invention is intended for use with photographic film or paper, or
The present invention relates to a sheet conveying device that surely adsorbs and conveys a sheet having a photosensitive layer on the surface of a master paper for electrophotographic plate making without damaging it.

(Prior Art) FIG. 2 is a view showing a conventional sheet conveying device in, for example, an electrophotographic plate making machine. That is, this electrophotographic plate making machine has a master paper supply unit 2 for accommodating roll-shaped plate making paper (hereinafter referred to as master paper 1B) made of, for example, zinc oxide paper, and a photosensitive surface facing downward from the master paper supply unit 2. Supplied as a master paper
A cutter 3 that cuts 1B into a predetermined length, a corona charger 4 that charges the cut master paper 1B, and a belt 11 that is a conveying means of the charged master paper 1B and that is composed of a plurality of belts 11 at intervals. , The rollers 12a and 12b for winding and driving the belt 11, the vacuum chamber 13 for sucking the back surface (anti-photosensitive surface) of the master paper 1B to bring it into close contact with the surface of the belt 11, and the air in the vacuum chamber 13. Vacuum pump 14 for decompressing, sensor means 15 for detecting that master paper 1B has been supplied, and detection signal SA from sensor means 15 in the middle of pipe 16 connecting vacuum chamber 13 and vacuum pump 14 Electromagnetic valve provided in 17
To the drive means 18 for controlling the opening / closing of the electromagnetic valve 17 and the pulse motor 1 for driving the rollers 12a and 12b.
A sheet conveying device 10 composed of 9 and a sheet conveying device 1
An exposure unit 5 provided below 0 for radiating image light;
It is composed of a lens 6 for forming an image on the master paper 1B of the image light emitted from the exposure means 5 to the original 21 placed with the image surface facing upward on the original placing table 20.

According to this apparatus, when the leading end of the master paper 1B supplied from the master paper supply unit 2 is detected by the sensor means 15 and this detection signal SA is input to the drive means 18,
The drive means 18 opens the electromagnetic valve 17, depressurizes the air in the vacuum chamber 13 by the vacuum pump 14, and sucks the master paper 1B through the suction holes 13a formed in the surface of the vacuum chamber 13 at a plurality of intervals between the belts 11. And Laura 1
When the master paper 1B is conveyed by a predetermined amount while the 2a and 12b rotate and the master paper 1B is in close contact with the surface of the belt 11, the master paper
The cutter 3 cuts 1B into a predetermined length, and the cut master paper 1B is sucked and conveyed by the belt 11. In this process, the corona charger 4 charges the master paper 1B, and the image light of the original 21 emitted from the exposing means 5 is imaged on the photosensitive surface of the master paper 1B by the lens 6 and after exposure, the master paper 1B is exposed. The belt 11 is carried out toward the developing section (not shown).

However, in the above-described sheet conveying apparatus 10, since the belt 11 is generally made of a material that can be wound, for example, an elastic member such as rubber or plastic, the roller 12
The lower surface of the a and 12b is stretched and hangs down due to its own weight, and the master paper 1B is placed in the vacuum chamber 13
It had the drawback of being difficult to suck. Even if the master paper 1B is sucked, as shown in the bottom view of the sheet carrying device 10 in FIG. 3, the size in the direction orthogonal to the carrying direction of the master paper 1B (the arrow shown in the figure) is larger than that in the portion where the intake holes 13a are present. If it is large, the belt 11 is
It is easy to come up on a and 11g, and belts 11a and 1g
When the weight of 1g is larger than the suction force, the belts 11a and 11g hang down, and the both ends of the master paper 1B are turned up, 11a → 11b →
There was a problem that it turned over in the order of 11c or 11g → 11f → 11e and dropped.

Therefore, for the purpose of solving the above problems, the present applicant has disclosed a sheet conveying device in an electrophotographic plate making machine as shown in FIG. 4 (JP-A-64-43431). That is, the belt 11 is not provided at both end portions in the direction orthogonal to the conveying direction of the master paper 1B (the arrow shown in the figure), and a plurality of intake holes are provided.
The surface of the vacuum chamber 13 is perforated with 13a.
Then, since both end portions of the master paper 1B are directly adsorbed on the surface of the vacuum chamber 13, the master paper 1B is not supported when the belt 11 is projected on the surface of the vacuum chamber 13.
Since it is impossible to flatten the belt, a concave portion slightly wider than the width of the belt 11 and slightly shallower than the thickness of the belt 11 is provided on the lower surface of the vacuum chamber 13, and the belt 11 runs in this concave portion to flatten the master paper 1B. And suck and convey. As described above, the both end portions of the master paper 1B are directly adsorbed to the surface of the vacuum chamber 13 so that the master paper 1B does not turn over and fall. And master paper
In order to smoothly suck and convey 1B, the frictional force between the master paper 1B and the belt 11 is made larger than the frictional force between the master paper 1B and the portion of the surface of the vacuum chamber 13 where there is no belt. If the suction holes 13a are provided at both end portions of the master paper 1B and the belts are provided inside the suction holes 13a as described above, the number and position of them can be set arbitrarily.

 The above is the sheet conveying apparatus disclosed.

(Problems to be Solved by the Invention) However, the above-described disclosed sheet conveying apparatus (Japanese Patent Application Laid-Open No. S60-18753)
64-43431), especially in the curled master paper 1B, both side edges thereof are turned up and eventually fall, which is a problem that the effect is not sufficient.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a sheet conveying device that reliably sucks and conveys a sheet with a simple structure.

Configuration of the Invention: (Means for Solving the Problem) The present invention relates to a sheet conveying device such as a master paper in an electrophotographic plate making machine, and an object of the invention is to convey a sheet and the sheet. And a suction means having a large number of suction holes for sucking the sheet, wherein the sheet is conveyed while being brought into close contact with the conveying means by the suction action of the suction means, in a direction orthogonal to the conveying direction of the sheet. This is achieved by providing a part of the air intake hole and forming an insulating material on the surface side of the suction means facing both end portions.

(Operation) In the sheet conveying device according to the present invention, by directly adsorbing both side ends of the sheet in the direction orthogonal to the sheet conveying direction and making the side of the suction means in contact with each other insulating, Since the attractive force due to static electricity is applied, the attractive force is strengthened as compared with the portions other than both side end portions.

Embodiment An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a diagram showing an embodiment of the sheet conveying apparatus of the present invention. The same components as those of the conventional one are designated by the same reference numerals and the description thereof will be omitted. In the embodiment of the present invention, as shown in the figure, the vacuum chamber 13 whose both end portions are in contact with the conveying direction of the master paper 1B.
The surface of the is formed by an insulating material having a smooth surface and good slipperiness by, for example, attaching insulating Teflon tapes 13b and 13c. Even if the portions other than the both end portions are made conductive, by forming the both end portions with the insulating material in this way, static electricity is generated between the both end portions of the master paper 1B facing the portion. Therefore, at the both side end portions, since the suction force due to static electricity is added to the suction force by the intake holes 13a, the suction force is strengthened as compared with the portions other than the both side end portions. Generally, the stronger the adsorption force is, the more the friction force is increased. However, this can be solved by using the insulating material having a smooth surface and slippery as described above.

(Modification) In the above-described embodiments, the case where the sheet conveying device is used for the electrophotographic plate making machine has been described, but the sheet conveying device is not limited to the electrophotographic plate making machine, and particularly the photosensitive surface such as a micro camera or a photo printer is used. The present invention can be used for all devices that convey the sheet.

Advantageous Effects of Invention As described above, according to the sheet conveying apparatus of the present invention, the surface portion of the suction means that directly adsorbs both end portions in the direction orthogonal to the sheet conveying direction is made insulative, thereby curling the sheet. Even if it is opposed, it can be sucked and transported smoothly and reliably without turning over from both ends and dropping. Further, when the material of the sheet is paper as a base, curling is likely to occur especially in a low humidity environment, but the lower the humidity, the more easily the electrically insulating portion is charged, so the adsorption force increases accordingly.

[Brief description of drawings]

FIG. 1 is a bottom view of a sheet conveying apparatus according to an embodiment of the present invention, FIG. 2 is a schematic configuration diagram of an electrophotographic plate making machine having a conventional sheet conveying apparatus, and FIG. 3 is a sheet conveying apparatus of FIG. And FIG. 4 is a perspective view of a conventional improved sheet conveying device. 1B …… Master paper, 10,30 …… Sheet conveying device, 11
...... Belt, 12a, 12b …… Roller, 13 …… Vacuum chamber, 13a …… Intake hole, 13b, 13c …… Insulating Teflon tape.

Claims (1)

(57) [Scope of utility model registration request] 1. A transport means for transporting a sheet, and a suction means having a plurality of suction holes for suctioning the sheet,
In a sheet conveying device that conveys the sheet while adhering to the conveying means by the suction action of the suction means,
A sheet conveying apparatus, which is provided with a part of the suction hole and is formed with an insulating substance on the front surface side of the suction means facing both end portions in the direction orthogonal to the sheet conveying direction. .