JP2007140332A - Toner replenishing and recovering mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner replenishing and recovering mechanism easily exchanging new toner and waste toner without an expensive sensor or a complicated control. <P>SOLUTION: The toner replenishing and recovering mechanism for an electrophotographic image forming device using a plurality of colors of toners is provided with; a waste toner buffer storing means to accumulate untransferred toner in an electrophotographic image forming process in one spot, a plurality of recovered toner transporting means to transport the recovered toner from a drum cleaner to a waste toner buffer storing means, and a recovered toner distributing means to distribute the toner accumulated in the waste toner buffer storing means according to the replenished ratio of the new toner. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a toner supply and recovery mechanism of a color image forming apparatus having a plurality of new toner containers and a plurality of waste toner containers.

  Conventionally, empty detection of a new toner container of an electrophotographic image forming apparatus using toner is performed by hitting a patch on a photoconductor to detect the density, and if it is thin, the replenishment operation is performed, and when the replenishment operation is performed several times, the patch still remains. The new toner container was detected as empty when the density did not rise above the set value.

Separately from the new toner container, waste toner full tank detection is configured on the waste toner storage container side or the ITB image transfer belt cleaner waste toner storage part to detect the full toner waste (for example, see Patent Document 1).
Japanese Patent Laid-Open No. 11-288203

  Attempts have been made to collect the collected toner collected by the image forming drum cleaner in a collecting container integrated with the new toner, which has been conventionally performed in the new toner replenishment and waste toner collecting system. However, the amount of collected toner varies due to the transfer efficiency, retransfer, etc., and the collected toner container is full even though the new toner still remains. I was forced to exchange.

  In some cases, a plurality of expensive toner sensors are used to detect the amount of collected toner.

  The present invention eliminates troublesome service such as replacement of waste toner of the ITB image transfer belt cleaner and replacement of waste toner of each color drum cleaner, and new toner and waste can be obtained without expensive sensors and complicated control. It is an object of the present invention to provide a toner replenishment / recovery mechanism capable of easily replacing toner.

  In order to achieve the above object, according to the first aspect of the present invention, in the toner replenishment and recovery mechanism of an electrophotographic image forming apparatus using a plurality of colors of toner, untransferred toner at the time of the electrophotographic image forming process is accumulated in one place. Waste toner buffer accommodating means, a plurality of collected toner conveying means for conveying the collected toner from the drum cleaner to the waste toner buffer accommodating means, and the toner accumulated in the waste toner buffer accommodating means according to the new toner replenishment ratio And a collected toner distributing means for distributing.

  According to a second aspect of the present invention, there is provided a waste toner buffer storage means for accumulating untransferred toner in one place in an electrophotographic image forming process in a toner replenishing and collecting mechanism of an electrophotographic image forming apparatus using a plurality of color toners. A plurality of collected toner conveying means for conveying the collected toner from the drum cleaner section and the ITB cleaner section to the waste toner buffer accommodating means, and a collection for distributing the toner accumulated in the waste toner buffer accommodating means in accordance with the new toner replenishment ratio. And a toner distribution unit.

  According to a third aspect of the present invention, in the toner replenishment and recovery mechanism of the electrophotographic image forming apparatus using a plurality of colors of toner, a plurality of developing means and a conveying means for conveying the new toner from each new toner containing means to each developing means The supply transport drive means for driving the supply transport means, the recovery transport drive means for driving the recovery transport means, the replenishment transport drive means, and the recovery transport drive means are connected by a drive means that does not have an irregular mechanism in the middle. It is characterized by always rotating at a constant rotation speed ratio.

  According to a fourth aspect of the present invention, in the toner replenishment / recovery mechanism of the electrophotographic image forming apparatus using a plurality of colors of toner, the plurality of new toner storage means and the new toner container / waste toner container are integrated or close to each other. A plurality of waste toner storage means that are simultaneously replaced, an ITB image transfer belt, an ITB image transfer belt cleaner, a waste toner buffer means with a stirring member that prevents coagulation, and a plurality of developments Means, a transport means for transporting toner from the ITB image transfer belt cleaner to the waste toner buffer means, a recovery transport means for transporting new toner from each new toner storage means to each developing means, and a supply transport for driving the supply transport means The drive means, the recovery transport drive means for driving the recovery transport means, the replenishment transport drive means and the recovery transport drive means are shifted in the middle. Structure are connected by drive means having no, and wherein the rotating always at a constant rotation speed ratio.

  According to the present invention, the waste toner is calculated based on the transfer efficiency + α of the total amount of the new toner, the waste toner buffer volume and the volume of each collected toner collection container are determined, and the waste toner is proportional to the replenishment amount of the new toner to the developing device. Since the toner is distributed to the collection container, it is possible to prevent the collection container from being filled with waste toner. As a result, the new toner container and the waste toner container can be synchronously exchanged, and if it is detected that the new toner has run out, it is not necessary to detect that the waste toner container is full, and the cost is reduced with a simple configuration. It leads to down.

  Further, if the new toner container and the waste toner container are made into an integrated cartridge, the container containing the waste toner can be exchanged without the user being aware of the waste toner, and usability equivalent to that of the one-component cartridge can be realized.

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

  1 is a schematic configuration diagram of an image forming apparatus to which the electrophotographic system of the present invention is applied, FIG. 2 is a diagram showing another embodiment of a schematic configuration diagram of an image forming apparatus to which the electrophotographic system of the present invention is applied, and FIG. FIG. 2 is a block diagram showing the concept of the present invention.

  In FIG. 1, an image forming unit 1 for forming an image on a sheet, a sheet conveying unit 2 for storing sheets and feeding them one by one to the image forming unit 1, and a reader scanner unit 3 for reading an image of a document. have.

  The image forming unit 1 includes a photosensitive drum 1 (1y, 1m, 1c, 1b) as an image forming body, and a charging roller 13 (13y, 13m, 1b) that primarily charges the surface of the photosensitive drum 1 around the photosensitive drum 1. 13c, 13b), an exposure device 9 for writing an image on the photosensitive drum 1 by means of a laser beam path as an image writing means, a yellow developing device 2y for developing a latent image formed on the photosensitive drum 1 into a visible image, magenta There are a developing device 2m, a cyan developing device 2c, and a black developing device 2b.

  Each color developing unit is provided with a yellow hopper 7y, a magenta hopper 7m, a cyan hopper 7c, and a black hopper 7b for supplying toner, and each color developing unit 7 (7y, 7m, 7c, 7b) supplies toner to each color developing unit. To be replenished. The latent image formed by laser exposure on the photosensitive drum 1 in accordance with the image signal is developed with each color developing sleeve to form a visible image.

  Toner remaining on the photosensitive drum 1 after the transfer of the primary charging roller 14 (14y, 14m, 14c, 14b) that transfers the visible image of the photosensitive drum 1 (1y, 1m, 1c, 1b) on the ITB belt 10 to each color. The collected toner collected by the drum cleaner 4 (4y, 4m, 4c, 4b) constituted by a cleaning blade and a conveying screw is collected in the collected toner buffer 6 by the conveying screw 5.

  The toner collected in the collected toner buffer 6 is collected in the collected toner container 8 (8y, 8m, 8c, 8b) by the toner conveying screw 6a and the conveying screw 6 (6y, 6m, 6c, 6b). The toner replenishing screw 3 (3y, 3m, 3c, 3b) and the toner recovery screw 6 (6y, 6m, 6c, 6b) are driven at a predetermined gear ratio 7 (7y, 7m, 7c, 7b) to replenish the toner. It rotates in synchronization with the rotation of the screw 3.

  The toner image transferred onto the ITB belt 10 is transferred onto the paper by the second transfer unit 24. The residual toner on the ITB belt 10 is cleaned by the ITB belt cleaning unit 11 and collected in the ITB collection toner box 12.

  On the other hand, the sheet on which the toner image has been transferred is conveyed to the fixing device 25, and heat and pressure are applied by the fixing device, whereby the toner image on the sheet is fixed on the sheet.

  The sheet feeding unit 2 is configured to feed the sheet in the left direction in FIG. 1 by contacting the uppermost sheet in the feeding cassette 21 above the feeding cassette 21 to stack and store the sheets. The image forming apparatus includes a pickup roller 22, a conveyance separation roller 23 that sends a sheet fed by the pickup roller 22 to a sheet conveyance that is continuous with the image forming unit 1, and a registration roller 27 that is arranged in front of the image forming unit 1.

  The sheet discharge unit 7 includes a discharge roller 26 that is a so-called in-body discharge structure that discharges paper to the upper space of the reader scanner 3 and the image forming unit 1.

  Although not shown, the reader scanner unit 3 includes a unit including image reading means such as a CCD, a contact image sensor light source, and a bent optical path mirror.

  In this embodiment, the image forming apparatus functions as a copier by irradiating the exposure device 9 with laser light based on the image of the original read by the reader scanner unit 3, or image data from a computer (not shown) or the like. Or a print command or the like and a laser beam based on the image data is emitted from the exposure device 9 to function as a printer. Further, it can function as a FAX receiver with a built-in FAX line.

  Next, the toner replenishment and waste toner collection mechanism will be described.

  1 to 3, the new toner containers 7 (7y, 7m, 7c, 7b) are independent from each other, and the waste toner collecting section 8 (in the lower part of the new toner containers 7 (7y, 7m, 7c, 7b) is provided. 8y, 8m, 8c, 8b) are provided. The new toner container 7 and the waste toner container 8 are integrated. Next, the toner supply operation relationship will be described step by step.

  1) For toner replenishment, the density of each color patch on the ITB belt 10 is detected by the patch detection sensor 15, and a new toner replenishment operation is performed when the density is equal to or lower than a set value. The color toner supply screw 2 (2y ′, 2m ′, 2c ′, 2b ′) whose patch density is less than the set value is driven, and a set amount of new toner is supplied to the screw 2 (2y ′, 2m ′, 2c ′). , 2b ′) to supply the developing device 2 (2y, 2m, 2c, 2b).

  2) The toner collected by the drum cleaning 4 (4y, 4m, 4c, 4b) is stored in the collected toner buffer 6 through the conveying screw 5 for each color. The recovered toner buffer 6 includes a stirring member 6z for preventing coagulation. The collected toner of the ITB cleaner 11 may also be stored in the collected toner buffer 6.

  3) The toner is conveyed from the collected toner buffer 6 to the collected toner containers 8 (8y, 8m, 8c, 8b) of the respective colors. A circulating screw 6a is driven to the collected toner buffer 6 to circulate the collected toner. The recovery toner screw 6 (6y, 6m, 6c, 6b) is directly connected to the drive of the supply screw 3 (3y, 3m, 3c, 3b) at a gear ratio 7g set, so that the supply screw 3 rotates. The collection screw 6 collects the collected toner in the collected toner container 8 only during the time during which the toner is collected.

  4) When empty of the new toner 7 is detected, it is determined that there is no toner when the density of the patch does not reach the set value even after the toner supply operation. At this time, waste toner proportional to the replenishment amount is collected in the collected toner container 8. Replacing the empty toner container completes the replenishment operation.

  The present invention can be widely used for a multifunctional multifunction machine equipped with a toner replenishment type electrophotographic image forming apparatus, a laser beam printer, and a fax machine.

It is a schematic block diagram of this invention. It is a schematic block diagram which is other embodiment of this invention. It is a block diagram which shows this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image formation part 2 Sheet | seat conveyance part 3 Leader scanner part 4 Drum cleaning part 5 Cleaning collection screw 6 Collected toner buffer container 7y, m, c, b New toner container 7g Drive gear train 8y, m, c, b Collected toner container 9 Laser exposure apparatus 10 ITB image transfer belt 11 ITB image transfer belt cleaning unit 12 ITB cleaner collection container 14 Primary transfer roller 15 Patch detection sensor

Claims (4)

In the toner supply and recovery mechanism of an electrophotographic image forming apparatus that uses a plurality of colors of toner,
Waste toner buffer accommodating means for accumulating untransferred toner in the electrophotographic image forming process in one place, a plurality of collected toner conveying means for conveying the collected toner from the drum cleaner to the waste toner buffer accommodating means, and waste toner A toner replenishing and collecting mechanism, comprising: a collected toner distributing means for distributing the toner accumulated in the buffer accommodating means in accordance with a new toner replenishing ratio. In the toner supply and recovery mechanism of an electrophotographic image forming apparatus that uses a plurality of colors of toner,
Waste toner buffer storage means for accumulating untransferred toner in the electrophotographic image forming process in one place, and a plurality of recovered toner transport means for transporting the recovered toner from the drum cleaner section and ITB cleaner section to the waste toner buffer storage means And a toner replenishing / recovering mechanism that distributes the toner accumulated in the waste toner buffer accommodating means in accordance with a new toner replenishing ratio. In the toner supply and recovery mechanism of an electrophotographic image forming apparatus that uses a plurality of colors of toner,
A plurality of developing means, a conveying means for conveying new toner from each new toner accommodating means to each developing means, a supply conveying driving means for driving the supply conveying means, a recovery conveying driving means for driving the collecting conveying means, and replenishment A toner replenishing and collecting mechanism, characterized in that the conveying driving means and the collecting and conveying driving means are connected by a driving means that does not have an irregular mechanism in the middle, and always rotate at a constant rotation speed ratio. In the toner supply and recovery mechanism of an electrophotographic image forming apparatus that uses a plurality of colors of toner,
The plurality of new toner storage means and the new toner container / waste toner container are integrated or arranged close to each other, the plurality of waste toner storage means to be replaced at the same time, the ITB image transfer belt, and the ITB image transfer Belt cleaner, waste toner buffer means with stirring member for preventing coagulation, a plurality of developing means, transport means for transporting toner from the ITB image transfer belt cleaner to waste toner buffer means, and each new toner storage means A recovery transport unit that transports new toner from the toner to each developing unit, a supply transport drive unit that drives the supply transport unit, a recovery transport drive unit that drives the recovery transport unit, a replenishment transport drive unit, and a recovery transport drive unit Are connected by a drive means having no speed change mechanism, and always rotate at a constant rotation speed ratio. Mechanism.

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