JPH0656326A - Image forming device - Google Patents

Abstract

PURPOSE:To provide an image forming device having a simply structured removal mechanism capable of removing transfer paper with metallic pieces stuck thereto. CONSTITUTION:An image forming device comprising a mechanism to carry paper sheets by means of a paper sheet carrying roller 2, wherein a wider magnet l which is provided in the paper sheet carrying roller 2 than transfer paper 8 or a paper carrying roller having the same shape as that of the roller 2, and paper discharging passages 6, 7, and 14 to discharge the transfer paper 8 with stuck metallic pieces 9 attracted to this paper carrying roller 2 out of the image forming device are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus used in a copying machine, a facsimile, etc., and more particularly to an image forming apparatus having a paper conveying mechanism for preventing paper jam due to metal pieces attached to transfer paper. is there.

[0002]

2. Description of the Related Art Conventionally, a transfer paper used in an image forming apparatus sometimes has metal such as a staple of a stapler. If it is used as it is, the metal may damage a part in the apparatus or a paper jam may occur. There was something to do. In order to solve such a problem, for example, Japanese Utility Model Laid-Open No. 63-116
Japanese Patent Publication No. 951 discloses an image forming apparatus in which a metal piece attached to a transfer paper is magnetically dropped into a groove provided in front of a paper feed roller to prevent the metal piece from entering the inside of the apparatus.

[0003]

However, in the above-mentioned conventional image forming apparatus, when a metal such as a staple of a stapler is attached to the transfer paper, it is often impossible to remove the metal piece only by magnetic force. When the attached transfer paper is conveyed, it causes a paper jam, and there is a problem that the inside of the apparatus has to be opened to remove the paper. Therefore, it is an object of the present invention to solve the above-mentioned conventional problems and provide an image forming apparatus having a removal mechanism having a simple structure, which can remove the transfer paper itself with the metal piece attached. .

[0004]

The gist of the present invention resides in that, in claim 1, in an image forming apparatus having a paper transport mechanism by a paper transport roller, a transfer paper width equal to or larger than a transfer paper width provided inside the paper transport roller is provided. It has a paper conveyance roller composed of a magnet having the same size or a magnet of the same shape, and a discharge path for discharging the transfer paper with metal attracted to the paper conveyance roller to the outside of the apparatus. Further, in claim 2, the magnet is non-rotating and has a fan shape corresponding to an arc of the outer circumference of the transport roller along the discharge path. According to a third aspect of the present invention, in an image forming apparatus having a paper transport mechanism with a paper transport roller, a paper transport provided inside the paper transport roller, the magnet having a size larger than the width of the transfer paper, or a magnet having a similar shape. A roller, a branch path for branching the metal-attached transfer paper attracted to the paper transport roller from a normal transport path, a paper detection means for detecting the transfer paper without metal, and the paper detection means. Has a control means for reversing the paper transport roller and discharging the transfer paper with metal to the original position when the transfer paper without metal is not detected at the scheduled time.

[0005]

Therefore, according to the first aspect of the present invention, when the transfer paper having the metal at the leading end comes in, the transfer paper is attracted to the paper transfer roller by the inside of the paper transfer roller (or the magnetic force of the paper transfer roller), and the paper transfer roller. Is carried along with the rotation of and is discharged to the outside of the apparatus through the discharge path. Further, in claim 2, when the transfer paper with metal at the leading end comes in, the transfer paper is attracted to the paper transfer roller by the inside of the paper transfer roller (or the magnetic force of the paper transfer roller), and the transfer roller is rotated. Although it is carried along, the magnet is non-rotating and has a fan shape corresponding to the arc of the outer circumference of the paper transport roller. Therefore, when the transfer paper passes the magnet part, the magnetic force becomes weak and the transfer paper is easily transferred. It becomes easy to leave the transport roller and enter the discharge path, and is discharged to the outside of the apparatus through the discharge path. Further, in claim 3,
When the transfer paper with metal at the tip comes in, the transfer paper is attracted to the paper transport roller by the inside of the transport roller (or the magnetic force of the paper transport roller), and the transfer paper without metal at the tip is carried. It branches from the transport path and is transported along the rotation of the paper transport roller. At this time, the paper detection means provided in the normal conveyance path detects that the transfer paper does not come even at the scheduled time, determines that the transfer paper has metal, and notifies the control means of the signal. Is output. As a result, the control means reverses the paper carrying roller to return the metal-attached transfer paper to the original position and eject it.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. An embodiment according to claim 1 is shown in FIG.
In the figure, a paper conveying roller 2 that abuts on a driving roller 3 with a predetermined pressure and has a magnet 1 fixed therein is rotatably mounted, and guides a transfer paper 8 to pass through the abutting portion. Paper transport guide plates 4 and 5 are provided. A guide plate 6 for guiding the transfer paper 8 attracted by the magnet 1 is provided behind the paper transport roller 2.
Claw 7 for peeling the transfer paper with metal on the downstream side
A guide sheet 7 for ejecting a transfer sheet having a and a guide plate 14 that closely faces and opposes the guide sheet 7 are provided, and the guide plates 7 and 14 form a discharge path. In this structure, after the transfer paper 8 having the metal 9 at its tip passes through the contact portions of the paper transport roller 2 and the drive roller 3, the metal is moved to the magnet 1
The sheet does not move to the normal conveyance path in which the sheet is guided by the guide plate 6 and is guided by the guide plate 6. The transfer paper 8 guided by the guide plate 6 is peeled off from the paper conveying roller 2 by the claw 7a at the tip of the guide plate 7, passes between the guide plates 7 and 14, and is discharged to the outside of the apparatus. Further, the transfer paper without the metal piece advances to the paper carrying guide plate 5 without being attracted to the paper carrying roller 2.

Next, an embodiment based on claim 2 will be described with reference to FIG. In the figure, the overall structure is the same as that of the embodiment of claim 1, but the difference is that, instead of the magnet 1 fixed to the paper carrying roller 2, it is independent of the rotation of the paper carrying roller 2. A fan-shaped magnet 12 which is fixed to the outer circumference of the paper transport roller 2 and which has a curved front end instead of the guide plate 14 is provided. There is. In this configuration, the transfer paper 8 with the metal 9 attached to the tip is the paper transport roller 2
After passing through the contact portion of the drive roller 3, the metal 9 advances in the direction in which the metal 9 is attracted by the magnet 12 and guided by the guide plate 6, and does not proceed to the normal conveyance path that advances the paper conveyance guide plate 5. The transfer paper 8 guided by the guide plate 6 is
After passing, the influence of the magnetic force of the magnet 12 disappears and the metal 9
Is slightly separated from the paper transport roller 2. Transfer paper 8 in this state
Enters the curved portion of the guide plate 15, passes between the guide plates 15 and 7, and is discharged to the outside of the apparatus. Further, the transfer paper 8 without the metal piece 9 advances to the paper carrying guide plate 5 without being attracted to the paper carrying roller 2.

Next, a third embodiment based on claim 3 will be described with reference to FIG. In the figure, the overall structure is substantially the same as that of the embodiment of claim 1, except that the guide plates 7 and 14 are not provided, and the paper detecting means for detecting the presence or absence of the transfer paper 8 is provided. The paper detection sensor 17 is attached to the paper conveyance guide plate 5, and the guide plate 20 that regulates the traveling direction of the transfer paper 8 is arranged close to the paper conveyance guide plate 4. Further, a control means (not shown) for reversing the drive roller 3 according to the detection result of the paper detection sensor 17 is provided. Here, the paper detection sensor 1
The distance between 7 and the contact points of the paper transport roller 2 and the drive roller 3 is set shorter than the distance from the front end to the rear end of the transfer paper 8. In this configuration, the transfer paper 8 having the metal 9 at its tip passes through the contact portion between the transport roller 2 and the drive roller 3, and then the metal 9 is attracted by the magnet 12 and guided by the guide plate 6. Proceed to step 5
Do not proceed to the normal transport route. In this case, a normal transfer paper without metal is advanced through the paper transport guide plate 5 and detected by the paper detection sensor 17, but the transfer paper 8 with metal 9 is not detected even at the scheduled time. Therefore, it is determined that the transfer sheet 8 has the metal 9 attached thereto, and this signal is output to the control means (not shown). The control means reversely rotates the drive roller 3 and conveys the transfer paper 8 in the direction opposite to the direction in which the transfer paper 8 has entered, whereby the guide plate 2
It is discharged from the original position while being regulated to 0. This operation is briefly shown in the flowchart as shown in FIG.
First, the transfer roller 2 is rotated in the forward direction to transfer the transfer sheet, and when the paper detection sensor 17 determines that the transfer sheet is present, the transfer roller 2 is normally rotated as it is, and when it is determined that there is no transfer sheet, the transfer roller 2 is moved. The transfer paper is returned to the original position in the same transport path by reversing.

[0009]

As described above, according to the first aspect of the present invention, the paper conveying roller provided inside the paper conveying roller, the magnet having a size larger than the width of the transfer paper, or the magnet having the same shape, and the paper conveying roller. Since it has a discharge path for discharging the metal-attached transfer paper drawn to the conveyor rollers to the outside of the device, the transfer paper with the metal (staple needle) at the tip came into the conveyor path. Even in this case, the paper can be discharged to the outside of the device without stopping the device. According to claim 2, the magnet is non-rotating and has a fan shape corresponding to the arc of the outer circumference of the paper transport roller along the discharge path. Therefore, the transfer paper with metal is attracted to the paper transport roller. After that, the magnetic force acting on the metal becomes weak and the transfer paper can be easily separated from the paper transport roller and smoothly enter the discharge path.
Further, according to the third aspect, a paper conveyance roller provided inside the paper conveyance roller and having a magnet having a size equal to or larger than the width of the transfer paper, or a magnet having a similar shape, and the transfer paper without metal are detected. Paper detection means and control means for reversing the paper transport roller to eject the transfer paper with metal to the original position when the paper detection means does not detect the transfer paper without metal at the scheduled time. Since it is provided with, the transfer paper having the metal (staple needle) at its tip can be discharged to the outside of the apparatus without separately providing a discharge path for discharging from the apparatus and without stopping the apparatus. Is.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of a paper carrying mechanism according to claim 1 of the present invention.

FIG. 2 is a schematic configuration diagram showing an embodiment of a paper transport mechanism according to claim 2 of the present invention.

FIG. 3 is a schematic configuration diagram showing an embodiment of a paper transport mechanism according to claim 3 of the present invention.

FIG. 4 is a flowchart showing an operation of the paper transport mechanism according to claim 3.

[Explanation of symbols]

 1,12 Magnet 2 Paper transport roller 8 Transfer paper 9 Metal piece 6,7,14 Discharge path 17 Paper detection means

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location G03G 15/00 108 7369-2H

Claims (3)

[Claims] 1. An image forming apparatus having a paper transport mechanism using a paper transport roller, wherein a paper transport roller provided inside the paper transport roller, the magnet having a size equal to or larger than a transfer paper width, or a magnet having the same shape, An image forming apparatus having a discharge path for discharging the metal-attached transfer paper attracted to the paper carrying roller to the outside of the apparatus. 2. The image forming apparatus according to claim 1, wherein the magnet is non-rotating and has a fan shape corresponding to an arc of the outer circumference of the conveying roller along the discharge path. 3. An image forming apparatus having a paper transport mechanism using a paper transport roller, comprising: a paper transport roller provided inside the paper transport roller, the magnet having a size larger than a transfer paper width, or a magnet having a similar shape. , A branch path for branching the transfer sheet with metal attracted to the paper transfer roller from the normal transfer path, a paper detection means for detecting the transfer paper without metal, and this paper detection means An image forming device comprising: a control unit for reversing the paper transport roller to eject the transfer sheet with metal to the original position when the transfer sheet without a mark is not detected at the scheduled time. apparatus.