JPH0445420B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a document conveying belt, and particularly to one designed to prevent static electricity.

[Technical Background of the Invention] A device that optically reads and processes an image on the surface of a document, such as an electronic copying machine, generally places the document on a glass platen and illuminates the surface of the document with a light source through the glass. The reflected image is formed on the photoreceptor and exposed to light.

Recently, an endless conveyor belt that moves along the glass surface of the document table has been installed inside the presser cover, and the document fed between this belt and the glass is automatically moved to the exposure position by the conveyor belt. There are copying machines that are configured to feed the paper up to a certain point and then automatically eject it after exposure.

It is necessary for the document conveying belt as described above to accurately convey the document without slipping, and for this purpose, it is preferable that the belt be seamless.

In addition, in copying machines that use such a conveyor belt, the document is continuously conveyed by the conveyor belt, so static electricity is generated due to friction between the glass of the document table and the conveyor belt, and the document is placed on the belt surface. There is a problem in that the particles adhere to each other and cannot be separated from the conveyor belt during discharge.

Various techniques have been proposed to solve these problems, and in particular, a technique in which the document conveying belt itself is made conductive has the advantage of simplifying the structure.

Therefore, among the structures that impart conductivity to the conveyor belt, if conductivity is imparted to at least the surface layer that contacts the document, at least no electrostatic attraction force will be generated between the conveyor belt and the document.

[Problems with the Background Art] However, the document conveyance belt is not simply a force transmitting member, but also conveys the document by adhering it to its surface layer, and the conveying force is due to the frictional force between the surface layer and the document. No, even if some electrostatic force exists, it will not be a major hindrance and may even be useful. Of course, electrostatic force must be avoided to the point where separation becomes impossible.

Furthermore, if a rubber material mixed with a conductive material is used as the surface layer material, there is a problem that, depending on the conductive material, when the surface layer comes into sliding contact with glass or the like, it may damage the other material.

Furthermore, if the belt has a seam, the uniformity of adhesion of the surface layer material at the seam tends to be hindered, and there is a problem in that the conductivity varies.

[Purpose of the Invention] This invention has been made in view of the above circumstances, and it is possible to prevent the generation of static electricity on the conveyor belt while also ensuring the conveyance of documents by having some electrostatic adhesion force. It is an object of the present invention to provide a document conveying belt having an adjusted structure that does not damage glass or the like.

[Summary of the Invention] Therefore, the document conveying belt of the present invention has a core material of
After immersing, drying, and heating a low-viscosity zipping liquid made by dissolving a rubbery material such as urethane in a solvent, the same rubbery material as described above is dissolved, and the zipping liquid has a higher viscosity than the zipping liquid. and a core conductive layer formed by coating and drying a first coating liquid formed by mixing a conductive material such as copper powder;
A second coating liquid, which is made by dissolving the same rubbery material as the first coating liquid in a solvent to approximately the same viscosity and lacks the conductive member, is applied in a single layer on at least the document side of the core conductive layer. Alternatively, it is constructed by a skin layer formed by coating multiple layers.

[Example] Hereinafter, an example of the present invention will be described with reference to FIGS.
This will be explained with reference to FIG. Note that FIG. 1 is a perspective view of the document conveyance belt, FIG. 2 is a sectional view showing the structure of the document conveyance belt, and FIG. 3 is a flowchart showing the manufacturing process.

The document conveyance belt of this embodiment is an endless belt as shown in FIG. 1, and is composed of a core conductive layer 1, an outer skin layer 2, and an inner skin layer 3. A fine recess 4 called .

The core conductive layer 1 is formed by coating a core material 5, such as natural fiber or synthetic fiber cloth, with a rubber material 7 mixed with a conductive member 6 such as copper powder.

The outer skin layer 2 and the inner skin layer 3 are formed by coating both surfaces of the core conductive layer 1 with white rubber material 8, for example, in three or two layers.

By the way, the outer epidermal layer 2 and the inner epidermal layer 3,
In particular, the outer skin layer 2 is required to be white and have a high coefficient of friction on the surface against the original, but low against the glass of the original stand, so the rubber material 8 must meet these conditions. For example, rubber materials such as urethane, polychloroprene, and chlorosulfonated polyethylene are used. Note that the same material as the rubber material 8 may be used for the rubber material 7 as well.

The document conveying belt having such a structure is manufactured by the steps shown in FIG.

First, raw threads such as natural fibers and synthetic fibers prepared in step S1 are woven into an endless (cylindrical) fabric in step 2, and then in step 3
The core material 5 is made by cutting it to an appropriate length.

On the other hand, the rubber material prepared in step 4, such as urethane rubber, is dissolved by adding a solvent in step S5, and stirred in step 6 to achieve a viscosity of 6000 to 6000.
Prepare a second coating solution of 8000 CPS. Then, in step S7, a solvent is further added to this second coating liquid to prepare a zipping liquid having a viscosity of 10 to 20 CPS.

Further, in step S8, copper powder is added to the second coating liquid in step S6 to prepare a conductive coating liquid, which is the first coating liquid.

In step S9, the fabric is dipped in zipping liquid, and then in step S10
Dry in . In step S11, this dried fabric is set in a current flow machine and heated, for example, at 130°C for about 10 minutes.

Next, both sides of the zipped fabric are coated with the conductive coating liquid obtained in step S8 (step S12), and dried in step S13 to form the core conductive layer 1.

Then, in step S14, the outside of the core conductive layer 1 is coated with the second coating liquid of step S6, and in step S15, it is dried at 30 to 35° C. for about 30 minutes. This coating and drying process was repeated two more times for a total of three coatings.
A three-layer outer skin layer 2 is formed.

After that, in steps S16 and S17, the inside of the core conductive layer 1 is coated and dried twice.
The inner epidermal layer 3 of the layer is formed.

The document conveying belt on which the skin layers 2 and 3 have been formed in this manner is press-vulcanized in step S18.

The heating plate used in this press vulcanization has a matte finish on its surface, and a so-called "texturing" process is simultaneously performed on the belt surface during press vulcanization. Therefore, fine recesses 4 are formed in the outer skin layer 2, that is, the surface of the belt after press vulcanization.

The belt after press vulcanization is left to stand naturally for about 1 to 5 hours in step S19.

By leaving it for several hours in this way, the internal distortions in the circumferential direction and width direction that occurred during the press vulcanization are removed. Then step this belt
In S20, the document is slit to a predetermined width to obtain a document conveyance belt.

In some cases, as shown by the broken line in Figure 3, after press curing in step S18, step S21 is performed.
The belt is hung on a rotating roller and rotated to prevent width shrinkage and curling, while drying the belt surface on which the recesses 4 are formed at 80° C. for about 20 minutes.
Then, in step S22, the fan is cooled for about 15 minutes.
Stabilizes belt circumference and prevents width shrinkage.

Further, in step S23, the belt is heated at a low temperature of about 5° C. to prevent the width of the belt from shrinking.

As a result, compared to the process of directly moving from step S18 to step S19, the time required for leaving the process in step S19 is shortened.

The document transport belt manufactured in this way is
A core material conductive layer 1 is formed by coating the core material 5 with a rubber material 7 mixed with a conductive material 6 such as copper powder,
This is coated with a white rubber material 8 such as urethane, polychloroprene, or chlorosulfonated polyethylene, so that at least the sliding surface of this conveyor belt with the conveyance surface is white, and the friction between the document and the conveyor belt is white. It has the property of stably transporting the original by overcoming friction with the surface, and also has the properties of an electrical conductor.

Therefore, conditions for stably transporting the document are obtained between the friction coefficient between the glass and the conveyor belt and the friction coefficient between the document and the conveyor belt, making it easier to convey the document. The drive device can be made smaller.

Furthermore, compared to friction between simple insulators, friction between an insulator and a conductor is less likely to generate static electricity, so even if a conductive conveyor belt rubs against an insulator such as glass or a document, , it becomes difficult to charge each other, and even if they are charged, the charge is easily removed through the core conductive layer 1. Therefore, the document is less likely to stick to the conveyance surface, and errors in conveyance of the document can be reduced.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment.

For example, the core material may be conductive or may contain a conductive material. Furthermore, conductive rubber may be used for the core conductive layer. Further, the core conductive layer may be one in which the core material is covered with a rubbery material and conductive rubber or a conductive member is interposed between the core material and the skin layer.

[Effects of the Invention] According to the document conveyance belt according to the present invention, in the document conveyance belt that conveys documents, a conductive material made of a core material in which a rubbery material is dissolved and a conductive material such as copper powder is mixed. A coating liquid formed by dissolving a rubbery material such as urethane, polychloroprene, or chlorosulfonated polyethylene without mixing the conductive material with the core conductive layer formed by the conductive coating liquid is applied to the core conductive layer. A surface layer formed at least on the sliding contact surface of the document is formed, and a core conductive layer mixed with a conductive material and a skin layer not mixed with a conductive material prevent static electricity on the conveyor belt. While preventing this from occurring, it also has some electrostatic adhesion to ensure that the document can be conveyed reliably and will not damage glass or the like.

[Brief explanation of drawings]

1 to 3 show an embodiment of the present invention, in which FIG. 1 is a perspective view of a document conveying belt, FIG. 2 is a sectional view showing the structure of the document conveying belt, and FIG. 3 is a document conveying belt. It is a flowchart showing the belt manufacturing process. 1... Core conductive layer, 2... Outer skin layer, 3...
Inner skin layer, 4... recess, 5... core material, 6... conductive member, 7, 8... rubber material.

Claims (1)

[Scope of Claims] 1. A document table on which a document is placed, and a document conveyance belt that conveys the document held between the document table, comprising: a core material; a rubber material is dissolved in the core material; And a core conductive layer formed from a conductive coating liquid made by mixing a conductive material such as copper powder, and a rubber material such as urethane, polychloroprene, chlorosulfonated polyethylene, etc. without mixing the conductive material. A document conveying belt comprising: a skin layer formed on at least the document sliding surface side of the core conductive layer; and a skin layer formed on at least the document sliding contact surface side of the core conductive layer. 2. In the document conveying belt according to claim 1, the core material conductive layer is made by dissolving a rubbery material such as urethane in a solvent by dissolving a core material formed by endless weaving. After dipping in a low viscosity zipping liquid, drying and heating, the same rubbery material as above is dissolved,
A document conveying belt formed by coating and drying a conductive coating liquid which has a higher viscosity than the zipping liquid and is made by mixing a conductive material such as copper powder. 3. In the document conveying belt according to claim 1, the skin layer refers to a non-conductive coating liquid formed by dissolving a rubber material similar to the conductive coating liquid in a solvent to approximately the same viscosity as the core. A document conveying belt formed by coating at least a single layer or multiple layers of a conductive layer on at least the document side.