JP2002274668A - Paper feeder and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paper feeder and an image forming apparatus capable of removing deposit such as paper dust or calcium carbonate from paper before paper feeding which is the start of copying operation, and preventing the above bad influence. SOLUTION: A front plate 4 on a spare tray 42 of a paper feed part 4 is provided with a blowing fan 422 and an air jet hole 423. The air jet hole 423 is opened in a position opposite to the leading end face of a sheaf of paper sheets stored in the spare tray 42. A rear plate opposite to the jet hole 423 with the sheaf of paper sheet interposed between them is provided with an air suction hole 425, and a suction duct 426 and an intake pipe 427 are provided on the downstream in the flow direction of the air. The intake pipe 427 is provided with a suction pump 428 for sucking air from the suction duct 426, and a collector 429 for collecting deposit such as powder dust.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feeder used for a copying machine, a printer or a facsimile machine for feeding paper to a predetermined portion of the apparatus, and a copying machine, a printer provided with these paper feeders, The present invention relates to an image forming apparatus such as a facsimile and, more particularly, to a sheet feeding apparatus and an image forming apparatus having a function of removing extraneous matter such as paper dust on the surface of a sheet.

[0002]

2. Description of the Related Art In an image forming apparatus typified by a printer or a copying machine, an image is formed on a sheet, and therefore, deposits such as paper dust and fine dust adhering on the sheet adversely affect image formation. It is known to give. Therefore, conventionally, a method of directly or indirectly removing these deposits from the start of sheet feeding has been adopted. The direct removal method is, for example, a method of removing the paper being transported by applying a brush or blowing air, and the method of indirect removal is performed on the surface of a paper feed roller or a transport roller. This is a method for removing adhering paper dust and the like.

However, these methods are performed after the paper feeding operation is started, and a technique for removing extraneous matter such as paper dust and dust on the paper surface before the paper feeding operation is particularly known. Not.

[0004]

By the way, paper is made of fibers and various chemical substances, and the fibers are cut by the stress during the paper manufacturing process, the packaging process, the transportation, the loading, and the like, and the fibers are cut off and adhered to the paper surface. Become. This becomes paper dust. Various substances are used as fillers, dyes, sizing agents, and the like for the paper. In particular, it has been recognized that calcium carbonate used as a filler has various adverse effects together with paper powder. Moreover, in recent years, many papers having a large amount of paper powder and calcium carbonate adhered to the surface have been sold.

This adverse effect is caused by a paper jam, a conveyance jam,
Examples include abnormal image generation, defective fixing, and toner recycling failure. The paper feed jam occurs, for example, when paper dust adheres to the surface of the paper feed roller and the frictional force decreases. The transport jam adheres to the surface of the transport roller and occurs due to a decrease in frictional force. An abnormal image is generated due to poor cleaning of the photoconductor surface. Insufficient fixing is caused by a decrease in the releasability of the toner from the toner adhered to the surface of the fixing roller. Further, an obstacle to the toner recyclability is caused by paper dust and the like mixed into the collected toner.

The present invention has been made in view of the above-mentioned circumstances of the prior art, and its purpose is to start a copying operation for deposits such as paper dust and calcium carbonate, which are the causes of these adverse effects. An object of the present invention is to provide a sheet feeder and an image forming apparatus which are removed from a sheet before the sheet is fed, and do not cause the adverse effect.

[0007]

In order to achieve the above object, the present invention relates to a sheet feeding apparatus for feeding a sheet to a portion where a predetermined process is performed, and a first sheet feeding tray for feeding a sheet to the portion. And a second paper supply tray for supplying paper to the first paper supply tray; and a removing device that removes deposits adhered to the paper surface of the paper loaded on the second paper supply tray. Means.

In this case, the removing means can be constituted by an air blowing device for blowing air onto the sheet bundle stacked on the second sheet feeding tray to remove paper dust. The image forming apparatus further includes a transfer unit that transfers the bundle of sheets stacked on the second sheet tray to the first sheet tray, and the transfer unit completes the attached matter removing operation by the removing unit. Thereafter, the sheet bundle is transferred. The air blowing device includes an air ejection port arranged to face one end face of the sheet bundle stacked on the second paper feed tray and an air ejection port arranged to face the other end face. A collecting device is provided downstream of the air suction port in the air flow direction with respect to the air suction port.

According to the present invention, there is provided a paper supply apparatus constructed as described above, and image data read from an image reading apparatus provided therein, image data transmitted from another apparatus, or read from a storage means. Image forming means for forming an image based on the obtained image data, wherein the image forming means forms an image on paper supplied from the paper supply device based on the image data. In the following embodiments, the first paper feed tray corresponds to the paper feed tray 41 and the second paper feed tray corresponds to the spare tray 42.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram showing the configuration of the entire copying machine. The copying machine 1 basically includes an image reading unit 2, an image writing unit 3, a paper feeding unit 4, and a document feeding unit 5. The image reading unit 2 is a known unit that scans a document by performing scanning in a main scanning direction by a so-called scanner and moving the document in a sub-scanning direction. A document is fed onto a contact glass by a document feeder 5 also called an automatic document feeder (ADF), and is optically read.

The image writing unit 3 includes a laser diode,
It is composed of a known optical system using a polygon mirror, fθ lens, etc., and shines light on the surface of the photoreceptor with this optical system, develops the latent image formed by the light writing into a visible image by toner development, and transfers it to paper. By doing so, an image is formed. After the formed image is fixed in the fixing unit, the image is discharged to a discharge tray by a discharge roller.

In this embodiment, the paper feed section 4 is provided in four stages, and one of them, here the uppermost paper feed stage 40, is divided into a paper feed tray 41 and a spare tray 42 as shown in FIG. And can be separately pulled out in a direction perpendicular to the paper surface (a direction perpendicular to the paper feeding direction). A vertical conveyance path 43 is provided in the sheet drawing direction on the right side in the drawing of the sheet feeding unit 4, and supplies the sheet drawn from each sheet feeding stage to the image writing unit 3. For this purpose, each paper feed stage is provided with a paper feed device 46 composed of a pickup roller 44 and a paper feed roller 45 as shown in FIG. 43. In the uppermost paper feed stage 40, the paper feed device 46 is provided on the side of the paper feed tray 41 from which paper is drawn. On the other hand, a transfer fence 47 is provided near the center of the rear end in the sheet conveyance direction on the spare tray 42, and when the sheet in the sheet feed tray 41 runs out, the transfer fence 47 is driven, and The stored sheet bundle is transferred to the sheet feed tray 41 in a lump. Here, although not particularly shown, a rear end fence is provided at the rear end of the paper feed tray 41 in order to regulate the position of the sheet bundle accommodated in the paper feed tray 41. The rear end fence is automatically opened when the sheet bundle is transferred from the spare tray 42 to the paper feed tray 41, and the sheet bundle can be moved to the spare tray.

As shown in the schematic configuration diagram of FIG. 3, a fan 422 for blowing air and an air outlet 423 are provided on a front side plate 421 of the sheet feeding section 4 on the side of the spare tray 42.
The air outlet 423 opens at a position facing the front end face of the sheet bundle stored in the spare tray 42. On the other hand, an air inlet 425 is opened in the rear plate 424 which faces the ejection port 423 with the sheet bundle interposed therebetween, and a suction duct 426 and an intake pipe 427 are provided on the downstream side in the air flow direction.
Is provided. In addition, in the intake pipe 427,
A suction pump 428 for sucking air from the suction duct 426 and a collector 429 for collecting the above-mentioned adhering matter such as paper powder mixed with the air are provided.

In the copier 1 configured as described above, the uppermost paper feed stage 40 is pulled out, the sheets are stacked on the drawn-out spare tray 42, and the spare tray 42 is set on the main body of the paper feed unit 4. It is electrically connected, and the power supply to the paper feed unit 4 is started. With this energization, the fan 422 installed inside the front side plate 21 starts rotating, and air is blown from the front side plate 422 side to the rear side plate 424 as shown by an arrow. By passing an appropriate amount of air, the air passes between the sheets. Also, the paper is vibrated by an appropriate amount of air blow, and the attached matter on the surface is set in a free state. Since the particle size of the adhered substance itself is as very small as several microns, the adhered substance separated from the surface of the paper by air is easily carried to the rear side plate 424.
The suction pump 428 is provided on the main body of the paper feeding unit 4 as described above, and sucks the blast in which the deposits are distributed through the suction duct 426. The deposits are collected by a filter or the like before the exhaust, and the deposits are collected in the collecting device 429. By executing such an attached matter collecting operation for an appropriate time, the attached matter on the surface of the sheet can be removed. When the adhering matter removal operation is completed, the right paper feed tray 41
After the paper is exhausted, the paper is transferred to the right paper feed tray 41 by the transfer fence 47. This operation is repeated every time paper is supplied to the spare tray 42.

In this embodiment, after the paper is supplied to the spare tray 42, air is blown for a predetermined time to perform the adhering matter removing operation. However, this operation is performed at predetermined intervals or when the power is turned on. It can also be set to do so. The setting of the operation time and the execution time of the attached matter removing operation can be appropriately set according to the installation environment of the copying machine and the paper consumption state.

[0017]

As described above, according to the present invention, the first paper supply tray for supplying paper to the paper supply portion and the second paper supply tray for supplying paper to the first paper supply tray And a removing means for removing the deposits adhering to the sheet surface of the sheets stacked on the second sheet feeding tray, so that the deposits such as paper dust and calcium carbonate can be copied. It is possible to provide a sheet feeder that removes sheets from the sheet before the start of sheet feeding and does not cause the adverse effect.

Further, according to the present invention, the removing means includes the second
Of the paper bundle stacked on the paper feed tray, the air blower removes the paper dust by blowing air, so that the paper bundle adheres to the surface of the paper before being transferred to the first paper tray. Deposits such as paper dust can be removed.

Further, according to the present invention, there is provided transfer means for transferring the bundle of sheets stacked on the second paper feed tray to the first paper feed tray at a time, and the transfer means is provided with an adhering substance by the removing means. After the removal operation is completed, the sheet bundle is transported, so that when the sheet bundle is stored in the first sheet feeding tray, all the deposits adhering to the sheet surface are removed and supplied from the first sheet feeding tray to the image forming position. Thus, when the image is formed, the attached matter does not adversely affect the image formation.

Further, according to the present invention, the air blowing device comprises an air ejection port arranged opposite to one end face of the sheet bundle stacked on the second sheet supply tray, and an air ejection port provided on the other side. Since the air suction port is provided so as to face the end face, it is possible to remove deposits attached to both sides of the sheet of paper by air.

Further, according to the present invention, since a collecting device for collecting the adhered substances separated from the surface of the paper is provided downstream of the air suction port in the air flow direction, the attachment separated from the surface of the paper is provided. It is possible to prevent the kimono from adhering again to the paper surface.

Further, according to the present invention, a paper supply device provided with the above-mentioned attached matter removing means, image data read from an image reading device provided therein, and an image transmitted from another device are provided. Data, or image forming means for forming an image based on the image data read from the storage means, wherein the image forming means forms an image on a sheet supplied from the sheet supply device based on the image data. As a result, image formation is performed on paper that has been removed before paper feeding, which is the start of the copying operation, for paper dust, calcium carbonate, and other deposits that cause adverse effects. High quality images can be formed.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a configuration of an entire copying machine according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing a configuration of an uppermost sheet feeding stage of the copying machine of FIG. 1;

FIG. 3 is a schematic configuration diagram of an attached matter removing device according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Copier 2 Image reading part 3 Image writing part 4 Paper supply part 40 Paper supply stage 41 Paper supply tray 42 Spare tray 421 Front side plate 422 Ventilation fan 423 Air outlet 424 Rear side plate 425 Air inlet 426 Suction duct 427 Intake Piping 428 Suction pump 429 Collection unit 43 Vertical conveyance path 46 Paper feeder 5 Document feeder

Claims (6)

[Claims] 1. A sheet supply device for supplying a sheet to a portion where a predetermined process is performed, wherein: a first sheet supply tray for supplying a sheet to the portion; and a first sheet supply tray for supplying a sheet to the first sheet supply tray. A sheet feeding device, comprising: a second sheet feeding tray; and a removing unit that removes an adhering substance attached to a sheet surface of the sheet stacked on the second sheet feeding tray. . 2. The paper according to claim 1, wherein said removing means comprises an air blowing device which blows air onto the paper bundle stacked on the second paper feed tray to remove paper dust. Feeding device. 3. A transfer device for transferring a bundle of sheets stacked on the second paper feed tray to the first paper feed tray at a time, wherein the transfer device performs an adhering matter removing operation by the removing device. 3. The sheet supply device according to claim 2, wherein the sheet bundle is transferred after the completion of the operation. 4. The air blowing device according to claim 1, wherein the air blowing device is arranged to face an end face of one side of the sheet bundle stacked on the second sheet feeding tray, and to face an end face of the other side. 3. The paper supply device according to claim 2, further comprising an air inlet provided. 5. The paper supply device according to claim 4, further comprising a collection device that collects adhered substances separated from the surface of the paper downstream of the air suction port in the air flow direction. 6. The paper supply device according to claim 1, wherein the image data is read from an image reading device provided therein, the image data is transmitted from another device, or is stored. Image forming means for forming an image based on image data read from the means, wherein the image forming means forms an image on a sheet supplied from the sheet supply device based on the image data. An image forming apparatus comprising: