JP2007171574A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To properly prevent toner scattering even when the degree of toner scattering changes due to a toner type, the degree of fatigue of toner, environment, and so on. <P>SOLUTION: The image forming apparatus includes a toner scattering information output means and a control means. On the basis of information about the degree of toner scattering, the image forming apparatus controls a suction device that sucks scattering toner. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image forming apparatus, and more particularly to a technique for removing scattered toner in an image forming apparatus.

  Many electrophotographic image forming apparatuses develop images using dry toner composed of fine powder particles to form an image.

  Since dry toner has the property of being easily scattered, in order to prevent contamination of the image forming apparatus due to the scattered toner, the scattered toner is sucked, the toner is removed by a dust collecting filter, and the air from which the toner has been removed is removed. A scattered toner removing device that discharges outside the image forming apparatus is provided in the image forming apparatus.

  Various contrivances have been proposed regarding the collection of scattered toner such as in Patent Documents 1 to 3, and in these proposals, by making the air volume variable, adverse effects caused by improving the dust collection efficiency and making the air volume excessive. It has been done to prevent.

  That is, in Patent Document 1, the air volume is changed depending on whether it is a monochrome image formation mode or a color image formation mode.

  In Patent Document 2, the exhaust fan drive speed is set to a different value depending on the image forming apparatus.

In Patent Document 3, the air pressure in the collective exhaust means that collects the air of the plurality of exhaust means is set to a predetermined value by controlling the air discharge amount in the plurality of exhaust means.
Japanese Patent Laid-Open No. 10-207309 JP 2001-194967 A JP 2004-354663 A

  It has been conventionally known that the degree of toner scattering in an image forming apparatus varies depending on the properties of the toner. For example, it is known that when the degree of toner fatigue progresses, the charging performance of the toner decreases and the toner tends to scatter.

  As described in Patent Documents 1 to 3, noise control and dust collection efficiency can be improved to some extent by controlling the air volume during toner collection. However, the conventional technology supports the ease of toner scattering. Since toner is not collected, toner scattering occurs, and harmful effects of collecting toner with an excessive air flow, for example, toner to be used for development are collected. Defects such as clogging the dust filter early have occurred.

  The present invention aims to solve such problems in the prior art.

The object is achieved by the following invention.
1.
An image forming apparatus comprising: a suction unit that sucks scattered toner; a scattering information output unit that outputs toner scattering degree information; and a control unit that controls the suction unit based on an output of the scattering information output unit.
2.
2. The image forming apparatus according to 1, wherein the scattering information output unit outputs the toner scattering degree information corresponding to a type of toner.
3.
3. The image forming apparatus according to claim 1, wherein the scattering information output unit outputs the toner scattering degree information according to an operation amount of the developing device.
4).
The image forming apparatus according to any one of 1 to 3, wherein the scattering information output unit outputs the toner scattering degree information according to an environment.
5.
5. The image forming apparatus according to claim 1, wherein the scattering information output unit outputs the toner scattering degree information corresponding to a color of toner.
6).
The image according to any one of claims 1 to 5, wherein the suction unit includes a fan, and the control unit controls the suction unit by controlling a rotation speed of the fan. Forming equipment.
7).
The suction means has a flow path of air containing scattered toner, and the control means controls the suction means by controlling the flow path. 2. The image forming apparatus according to item 1.
8).
8. The image forming apparatus according to any one of claims 1 to 7, further comprising a storage unit that stores a correspondence table of control values with respect to the output of the scattering information output unit.

  According to the present invention, since the suction unit is controlled based on the output of the scattering information output unit that outputs information on the degree of scattering of toner, proper toner collection is always performed, and toner scattering due to insufficient collection or excessive Detrimental effects due to collection are well prevented.

<Image forming apparatus>
The present invention will be described below based on an embodiment, but the present invention is not limited to the embodiment. FIG. 1 is a schematic configuration diagram of a color image forming apparatus as an embodiment of an image forming apparatus according to the present invention.

  The image forming apparatus includes an image forming unit Y that forms a yellow image, an image forming unit M that forms a magenta image, an image forming unit C that forms a cyan image, and an image forming unit K that forms a black image. The unit includes a photoreceptor 1, a developing device 2, a latent image forming device 3, a transfer device 4, and a cleaning device 5. The latent image forming apparatus 3 includes a charging device that charges the photosensitive member 1 and an exposure device that exposes the image of the photosensitive member 1. The intermediate transfer member 6 is disposed to face the image forming units Y, M, C, and K.

  In the image forming portions Y, M, C, and K, the formed single color toner image is transferred to the intermediate transfer member 6 by the transfer device 4, and transferred from the intermediate transfer member 6 to the recording material P by the transfer device 7, and the intermediate transfer member. A color toner image is formed on 6.

  The color toner image on the intermediate transfer member is transferred to the recording material P by the transfer device 7 and fixed by the fixing device 8. A cleaning device 9 cleans the intermediate transfer member after transfer.

  The scattered toner generated in the vicinity of the developing device 2 is removed by the airflow indicated by arrows WY, WM, WC, and WK. The airflow is formed by the suction devices 10Y, 10M, 10C, and 10K, and each of the suction devices 10Y, 10M, 10C, and 10K includes a dust collection filter and a fan.

  FIG. 2 is a block diagram showing the basic configuration of the control system in the present invention.

  Although the suction devices 10Y, 10M, 10C, and 10K in FIG. 1 are collectively indicated by 10 in FIG. 2, the control unit 11 individually controls the suction devices 10Y, 10M, 10C, and 10K in FIG.

  The control means 11 controls the suction device 10 based on the information from the scattering information output means 12 that outputs information representing the degree of toner scattering, and changes the air volume.

The degree of toner scattering varies for various reasons as follows.
(1) Type of toner The degree of scattering varies depending on the particle size of the toner. Usually, since a specific toner is used in a specific image forming apparatus, the scattering information output means 12 does not output different information depending on the type of toner in the specific image forming apparatus. The scattering information output unit 12 of the apparatus is initially set according to the type of toner used in the image forming apparatus, and outputs scattering degree information corresponding to the scattering degree of the used toner.

Further, since the degree of scattering varies depending on the toner color, the scattering information output means outputs the degree of scattering information corresponding to each single color toner.
(2) Fatigue degree of developer of toner In the developing device 2, the developer is agitated. Due to this agitation, the toner and the carrier are fatigued, the chargeability of the toner is lowered, and the scattering degree is reduced. Rises.

The scattering information output means 12 outputs scattering degree information that changes in accordance with the operating amount of the developer carrier in the developing device 2, that is, the accumulated rotation amount of the developer carrier. Specifically, the scattering degree information that rises as the operating amount of the developer carrier increases.
(3) Environment The degree of toner scattering changes according to at least one change in temperature and humidity. That is, the lower the temperature and the lower the humidity, the higher the scattering degree.

  The scattering information output means 12 detects an environmental change and outputs scattering degree information corresponding to the environment.

  The control unit 11 controls the suction device 10 based on the scattering degree information output from the scattering information output unit 12.

  As a control method, there is a method of changing the suction air volume by controlling the rotational speed of the fan 10a shown in FIG. 3 or changing the suction air volume by controlling the blade 10b and changing the area of the suction port. A combination of these can also be used.

  A program for changing the control amount of the suction device 10 in accordance with the type of toner, the degree of developer fatigue, and the environment, that is, a correspondence table of air flow control values corresponding to the output of the scattering information output means 12 is stored in the storage device 13 in advance. The control means 11 controls the suction device 10 with reference to the data stored in the storage means 13.

  In FIG. 4, the developer carrying member 2 a of the developing device 2 rotates with respect to the photosensitive member 1 as indicated by an arrow, and the electrostatic latent image on the photosensitive member 1 is developed.

In the examples described below, the degree of toner scattering is indicated by the amount of scattering (g) per 10 km travel distance of the peripheral surface of the developer carrier 2a. The percentage of the air volume is expressed as an increase rate with respect to the reference air volume, where the reference air volume is 100.
(1) Example 1
As a result of air volume control shown in Table 1 for toner A having a toner scattering degree of 0.25 g / 10 km and toner B having a toner scattering degree of 0.05 g / 10 km, toner scattering was prevented satisfactorily. .

(2) Example 2
The toner scattering degree shown in Table 2 is measured with respect to the movement amount 0 to 25 km, 25 to 50 km, and 50 to 75 km of the peripheral surface of the developer carrier 2a in FIG. 4, and the air volume is changed as shown in Table 2. As a result, good scattering prevention was achieved.

(3) Example 3
By performing the air volume control shown in Table 3 with respect to changes in temperature and humidity, it was possible to prevent good scattering.

1 is a schematic configuration diagram of a color image forming apparatus as an embodiment of an image forming apparatus according to the present invention. It is a block diagram of the control system which performs air volume control. It is a figure which shows a suction device. It is a figure which shows a developing device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Suction apparatus 11 Control means 12 Scatter information output means 13 Storage means

Claims (8)

An image forming apparatus comprising: a suction unit that sucks scattered toner; a scattering information output unit that outputs toner scattering degree information; and a control unit that controls the suction unit based on an output of the scattering information output unit. The image forming apparatus according to claim 1, wherein the scattering information output unit outputs the toner scattering degree information corresponding to a type of toner. The image forming apparatus according to claim 1, wherein the scattering information output unit outputs the toner scattering degree information according to an operation amount of the developing device. The image forming apparatus according to claim 1, wherein the scattering information output unit outputs the toner scattering degree information according to an environment. The image forming apparatus according to claim 1, wherein the scattering information output unit outputs the toner scattering degree information corresponding to a color of toner. The said suction means has a fan, The said control means controls the said suction means by controlling the rotational speed of the said fan, The Claim 1 characterized by the above-mentioned. Image forming apparatus. 7. The suction unit according to claim 1, wherein the suction unit has a flow path of air containing scattered toner, and the control unit controls the suction unit by controlling the flow path. The image forming apparatus according to claim 1. The image forming apparatus according to claim 1, further comprising a storage unit that stores a correspondence table of control values with respect to the output of the scattering information output unit.

Images