JP2970428B2 - Image forming apparatus and toner band forming method thereof - Google Patents

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 such as a copying machine, a printer, or a facsimile machine, and more particularly to ensuring the lubricity of a cleaning device and the copy paper by using a toner band formed on a non-image portion of an image carrier. The present invention relates to an image forming apparatus which removes a component adherence to prevent dripping of an electrostatic latent image and a method of forming a toner band thereof.

[0002]

2. Description of the Related Art In an electrophotographic copying machine, a printer, or a facsimile image forming apparatus, a latent image based on a document image is formed on a photosensitive member serving as an image carrier, and the latent image is developed using toner. The toner image is transferred to a recording medium such as copy paper to reproduce the image, and a cleaning process for removing the toner remaining on the image carrier is performed.

FIG. 7 is a schematic diagram for explaining the structure of a conventional main part of an image forming apparatus of this type.
Is an image forming unit, 1a is an exposure lamp, 1b is an optical scanning system,
1c is a mirror, 1d is a condensing lens, 2 is an image carrier, 3 is a developing device, 4 is a cleaning device, 5 is a non-image portion charge removing lamp, 6 is a charger, and 7 is a charge removing lamp. In FIG. 1, an image forming unit 1 includes an exposure lamp 1a for illuminating a document, an optical scanning system 1b including a plurality of mirrors 1c for scanning the reflected light on a photoconductor as an image carrier 2, and a condenser lens 1d. It is composed of

[0004] The surface of the image carrier 2 is uniformly charged by a charger 6, and an electrostatic latent image corresponding to a document image is formed by scanning the surface of the image carrier 2 with the optical scanning system 1b. After the electrostatic latent image is developed with toner by the developing device 3, it is transferred to transfer paper (copy paper) not shown. The untransferred toner remains on the image carrier 2 after the transfer, and
The residual toner is removed by the cleaning device 4.

Further, the transfer sheet comes into contact with the image carrier 2 when the toner image is transferred, so that components of the transfer sheet adhere to the transfer sheet, which causes disturbance of the electrostatic latent image. Therefore, a toner band is formed on a non-image portion of the image carrier 2 and toner is supplied by the toner band at the time of cleaning by the cleaning device. Is to be removed.

As described above, generally, in an image forming apparatus provided with a blade type cleaning device,
In order to ensure the lubricity of the cleaning blade and the seal of the cleaning device, or to improve the cleaning performance of the image carrier, a toner band is formed on the non-image portion, and the untransferred toner band is supplied to the cleaning device. It is configured as follows.

As a prior art relating to a method of forming a toner band in an image forming apparatus provided with such a cleaning device using a toner band, Japanese Patent Application Laid-Open No. 58-1529 is disclosed.
As disclosed in JP-A-79-180 and JP-A-61-120180, a black band is printed on the non-document portion of the document table, and the black band is also scanned during the copying operation, and exposed and developed. There is known an image bearing member that forms a toner band as an image of the black band on an image carrier.

Japanese Patent Application Laid-Open No. Sho 64-64 discloses a method in which the amount of charge is controlled by controlling the timing of shutting off the charging device and the discharging lamp, or by stopping the developing device and the timing of shutting off the charging device and the discharging lamp. −10859
No. 2 discloses this.

[0009]

However, in the above-mentioned prior art, the above-mentioned method requires a space for printing a black band on the non-document portion of the document table, and it is necessary to scan the black band printing portion without fail. At the same time, when the copy magnification is changed, the width and length of the image on the image carrier changes according to the copy magnification because the printing part of the black band is located on the object side of the optical lens of the scanning system. There was a problem that it was difficult to supply the amount stably.

Further, the latter method of controlling the timing of shutting off the charging device and the discharging lamp and controlling the timing of stopping the toner developing device, the discharging lamp, and the amount of charge to form the toner band complicates the timing control. There has been a problem that it is difficult to supply a stable amount of toner to the cleaning device because the accuracy of the width of the toner band is hardly obtained. In these conventional techniques, the toner band to be created cannot be confirmed, and it becomes more difficult to create an accurate toner band as the process speed of the image forming apparatus increases.

A first object of the present invention is to solve the above-mentioned problems of the prior art, to form a required toner band accurately, and to make a toner band actually formed visible to a stable cleaning device. An object of the present invention is to provide an image forming apparatus capable of supplying an amount. A second object of the present invention is to provide a toner band forming method for supplying toner to a cleaning device in the image forming apparatus.

[0012]

According to a first aspect of the present invention, there is provided an image exposure section having an exposure lamp and an optical scanning system. An image carrier 2 on which an electrostatic latent image is formed by optical scanning of an exposure unit, and a developing device 3 for developing the electrostatic latent image on the image carrier with toner
And an image forming unit including at least a blade-type cleaning device 4 for cleaning the toner on the image carrier and a non-image-portion discharging lamp 5 for removing charges from a non-image portion of the image carrier. In the image forming apparatus,
First control means 8 for turning off the non-image portion static elimination lamp 5 when the light amount of the exposure lamp falls after a predetermined time period in which the formation of the electrostatic latent image is possible with reference to the timing of turning off the exposure lamp 1a; Exposure lamp 1 for multiple copies
a second control means 9 for synchronizing the center of the non-image portion neutralization lamp 5 with the minimum amount of light from rise to fall by turning off and lighting of a,
A third control unit for controlling the formation of an electrostatic latent image of a toner band on the image carrier using the non-image portion discharging lamp at the time of the backward scanning of the image exposure unit; The developing device 3 develops a toner band formed by developing the electrostatic latent image having a predetermined width formed by the third control means 10 under the control of the control means 8 or the second control means 9. And a fourth control means for cleaning with the cleaning device.

According to a second aspect of the present invention, in the first aspect, an exposure lamp history data storage means 13 for storing a change in a use condition of the exposure lamp 1a; And a correction value storage means 14 for storing a time correction value set in advance in accordance with the correction value. The correction value storage means 14 stores the time correction value output from the first control means 8 based on the correction value read from the correction value storage means 14. It is characterized in that the turning-off timing of the image section static elimination lamp 5 is controlled.

[0014] Further, a third invention according to a third aspect is characterized in that:
In the first or second invention, a developing bias changing unit 15 for changing a developing bias of the developing device 3 is provided,
The developing bias of the developing device 3 is changed based on the timing of turning off the exposure lamp by the first control means 8. Further, according to a fourth aspect of the present invention, in the first to third aspects, the image forming apparatus further comprises a toner band adjustment mode setting means 16, wherein the toner band adjustment mode is set by the toner band adjustment mode setting means 16. The non-image portion static elimination lamp 5 is turned off to change the toner band width.

[0015] The fifth invention according to claim 5 is as follows.
Image exposure unit 1 having exposure lamp 1a and optical scanning system 1b
An image carrier 2 on which an electrostatic latent image is formed by scanning of the image exposure unit; a developing device 3 for developing the electrostatic latent image on the image carrier with toner; and cleaning the toner on the image carrier. A blade-type cleaning device 4, a non-image-portion discharging lamp 5 for removing a non-image portion of the image carrier 2,
A method for forming a toner band in an image forming apparatus including at least an image forming unit including at least a charging device 6 for uniformly charging the image carrier 2, wherein the charging device 6 removes the image carrier 2. And the non-image-portion discharging lamp 5 is turned off when the exposure lamp falls after a predetermined time during which an electrostatic latent image can be formed with reference to the extinguishing timing of the exposure lamp 1a during single-sheet copying. A first toner band portion electrostatic charge remaining process for turning off the light, and a non-image portion charge removing lamp 5 at a portion where the amount of light falls from the fall to the rise due to the extinguishing and lighting of the exposure lamp 1a during multiple copying. A second toner band portion electrostatic charge remaining process for synchronizing the center of the light-off time, and the first toner band portion electrostatic charge remaining process or the second toner band portion electrostatic charge remaining process. Characterized in that it comprises at least a residual electrostatic charge width created a residual electrostatic charge development step of developing by the developing apparatus 3 in.

According to a sixth aspect of the present invention, there is provided an image exposure section 1 having an exposure lamp 1a and an optical scanning system 1b, and an image on which an electrostatic latent image is formed by scanning of the image exposure section. A carrier 2, a developing device 3 for developing the electrostatic latent image of the image carrier with toner, a blade-type cleaning device 4 for cleaning toner on the image carrier, and a non-image portion of the image carrier 2. Non-image part static elimination lamp 5 for static elimination
A charging device 6 for uniformly charging the image carrier 2 and an image forming unit including at least a toner band adjustment mode setting unit 16. A step of setting the toner band adjustment mode by the toner band adjustment mode setting means 16; a step of uniformly charging the image carrier 2 by the charging device 6; and the extinguishing of the exposure lamp 1a during single-sheet copying. When the exposure lamp falls after a predetermined time in which an electrostatic latent image can be formed with reference to the timing, the non-image portion charge removing lamp 5 is turned off for a time based on an adjustment input from the toner band adjustment mode setting means 16. First
And the central portion of the non-image portion static elimination lamp 5 in the portion where the amount of light from the fall to the rise due to the extinguishing and lighting of the exposure lamp 1a during multiple copying is the lowest. And a transfer timing for changing the paper feed timing and the scanning timing of the image exposure unit 1 when the toner band adjustment mode is set by the toner band adjustment mode setting unit 16. Change process,
A developing step of developing the remaining electrostatic charge width created in the first toner band portion electrostatic charge remaining step or the second toner band portion electrostatic charge remaining step by the developing device 3; And a toner band transferring step of transferring the toner band formed on the image bearing member onto paper.

[0017]

In the configuration of the first aspect of the invention, the first control means 8 determines the fall of the light amount of the exposure lamp 1a after a predetermined time period in which the formation of the electrostatic latent image is possible with reference to the timing of turning off the exposure lamp 1a. At this time, the non-image portion static elimination lamp 5 is turned off. The predetermined time during which the electrostatic latent image can be formed is stored in the predicted value storage unit 8a as a predicted value obtained by actual measurement in advance.

The second control means 9 synchronizes the center of the extinguishing time of the non-image portion static elimination lamp 5 with the portion where the light quantity rises and falls by the extinguishing and lighting of the exposure lamp at the time of plural copying. . Third control means 10
Controls the formation of an electrostatic latent image of a toner band on the image carrier 2 by using the non-image portion discharging lamp 5 during the backward scanning of the image exposure section 1.

The fourth control means 12 applies the electrostatic latent image of a predetermined width formed by the third control means 10 under the control of the first control means 8 or the second control means 9 to the above. The toner band developed by the developing means is cleaned by the cleaning device 4. In the configuration of the second invention, the exposure lamp history data storage means 13 is provided.
Exposure lamp history data storage means 13 for storing a change in the use condition of the exposure lamp 1a, and a time correction value set in advance corresponding to the history data of the exposure lamp, and read out from the correction value storage means 14. The non-image portion static elimination lamp output from the first control means 8 is turned off timing based on the corrected value.

Further, in the constitution of the third invention, there is provided a developing bias changing means 15 for changing a developing bias of the developing device 3, and the developing bias changing means 15 changes the developing bias of the developing device 3 with reference to the timing of turning off the exposure lamp 5 by the first control means 8. Developing device 3
Characterized in that the developing bias of the developing device is changed. Still further, in the configuration of the fourth invention, the toner band adjustment mode setting means 16 sets the toner band adjustment mode when:
The non-image portion static elimination lamp 5 is turned off to change the toner band width.

In the fifth aspect of the invention, in the charging step, the image carrier 2 is uniformly charged by the charging device 6. The first toner band portion electrostatic charge remaining step is a process for removing the non-image portion when the exposure lamp falls after a predetermined time during which an electrostatic latent image can be formed with reference to the extinguishing timing of the exposure lamp when copying a single sheet. The lamp 5 is turned off.

In the second electrostatic charge remaining step in the toner band portion, the non-image portion static elimination lamp 5 is turned off at a portion where the light amount is lowest from the fall to the rise due to the extinguishing and lighting of the exposure lamp at the time of plural copies. Synchronize the center of time. In the remaining electrostatic charge developing step, the developing device 3 develops the remaining electrostatic charge width created in the first toner band part electrostatic charge remaining step or the second toner band part electrostatic charge remaining step.

Further, in the configuration of the sixth invention,
In the mode setting step, the toner band adjustment mode is set by the toner band adjustment mode setting means 16. In the charging step, the image carrier 2 is uniformly charged by the charging device 6. The first toner band portion electrostatic charge remaining step is a process for removing the non-image portion when the exposure lamp falls after a predetermined time during which an electrostatic latent image can be formed with reference to the extinguishing timing of the exposure lamp when copying a single sheet. The lamp 5 is turned off for a time based on the adjustment input from the toner band adjustment mode setting means 16.

In the second electrostatic charge remaining step of the toner band portion, the non-image portion static elimination lamp 5 is turned off in a portion where the light amount is the lowest from the fall to the rise due to the extinguishing and lighting of the exposure lamp at the time of plural copying. Synchronize the center of time. In the transfer timing changing step, the paper feeding timing and the scanning timing of the optical scanning system 1b are changed when the toner band adjustment mode is set by the toner band adjustment mode setting means 16.

In the remaining electrostatic charge developing step, the remaining electrostatic charge width created in the first toner band part electrostatic charge remaining step or the second toner band part electrostatic charge remaining step is determined by the developing device 3. develop. In the toner band transfer step, the toner band formed on the image carrier is transferred onto a sheet. The toner band width can be easily adjusted by rewriting the data in the correction value storage means 14 with a numeric keypad or the like while visually checking the toner band transferred to the paper.

As described above, according to the present invention, an image exposing device for exposing a non-image portion on an image carrier to form a toner band, a non-image portion charge removing lamp, and a charger are used. Is accurately synchronized, a stable toner band can be reliably formed even when the process speed increases, and a stable amount of toner can be supplied to the cleaning device.

[0027]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic diagram for explaining the configuration of a first embodiment of an image forming apparatus according to the present invention, wherein 1 is an image exposure section, 1a is a fluorescent lamp or a fluorescent lamp which is turned on at the time of forward movement during document scanning and turned off at the time of backward movement. An exposure lamp composed of a halogen lamp, 1b is an optical scanning system for guiding the reflected light from the document to the photosensitive drum 2, and 2 is a photosensitive member that carries an electrostatic latent image and a toner-developed visual image. A drum 3 is a developing device for developing an electrostatic latent image formed on the photosensitive drum 2 with toner, 4 is a blade type cleaning device for scraping toner on the surface of the photosensitive drum 2, and 5 is an unnecessary charge or latent charge. A non-image portion charge eliminating lamp for erasing an image before forming a latent image, 6 a charger for uniformly charging the surface of the photosensitive drum 2 to a positive or negative polarity, and 7 a residual charge on the photosensitive drum 2 A static elimination lamp 8 for removing electric charges, Means 8a is a predicted value storing means for storing a value obtained by previously measuring a predetermined time during which an electrostatic latent image can be formed as a predicted value; 9 is a second control means; 10 is a third control means; Is a fourth control means.

Referring to FIG. 1, the image forming apparatus includes an image exposure section 1 having an exposure lamp 1a and an optical scanning system 1b, an image carrier 2 on which an electrostatic latent image is formed by optical scanning of the image exposure section. A developing device 3 for developing the electrostatic latent image of the image carrier with toner, a blade-type cleaning device 4 for cleaning the toner on the image carrier, and a non-image portion static elimination for eliminating the non-image portion of the image carrier And an image forming unit having at least a lamp 5 for use.

The first control means 8 calculates the value stored in the predicted value storage means 8a when the light quantity of the exposure lamp falls based on the timing of turning off the exposure lamp 1a. The non-image portion static elimination lamp 5 is read out as a predetermined time during which formation is possible, and the non-image portion static elimination lamp 5 is turned off. The center of the extinguishing time of the non-image portion static elimination lamp 5 is synchronized.

The third control means 10 forms the electrostatic latent image of the toner band on the image carrier 2 by using the non-image area discharging lamp 5 during the backward scanning of the image exposure section 1. And the fourth control means 12 controls the operation of the first control means 8
Alternatively, the toner band formed by developing the electrostatic latent image having a predetermined width formed by the third control unit 10 by the developing device 3 under the control of the second control unit 9 is removed by the cleaning device 4. To clean.

The cleaning device in this embodiment is
The transfer paper component (deletion component) is removed together with the toner by cleaning the toner band formed on the non-image portion of the photosensitive drum 2. During continuous copying, the toner band is located between the electrostatic latent image forming portions of the copy.
Further, at the time of one-sheet copy, it is obtained by forming an electrostatic latent image for a copy band for each copy after the formation of the electrostatic latent image is completed, that is, in a non-image portion.

FIG. 2 is an operation timing chart for explaining the operation of the first embodiment of the image forming apparatus according to the present invention.
(A) is the on / off timing of the charger, (b) is the on / off timing of the non-image portion static elimination lamp, (c) is the on / off timing of the exposure lamp, and (d) is the light level (relative) of the exposure lamp. Value). Hereinafter, the operation of FIG.
This will be described with reference to FIG.

In order to form an electrostatic latent image for a toner band between copies during continuous copying, first, as shown in FIG. And is uniformly charged to the potential. Thereafter, when the scanning of the image exposure section 1 is started and the exposure of the document is completed, the optical scanning system 1b returns to the home position. As shown in FIG. 2C, when the optical scanning system 1b returns, that is, moves back, the exposure lamp 1a is turned off. The extinguishing time of the exposure lamp 1a is a period during which there is no support for scanning the original for the next copy, and the exposure lamp 1 is turned on again for the next exposure.

As shown in FIG. 2 (b), the first control means 8 performs the above-mentioned operation after a predetermined time period during which the electrostatic latent image can be formed with reference to the timing (a) of turning off the exposure lamp 1a. When the light amount of the exposure lamp falls, the value stored in the predicted value storage means 8a is read out as a predetermined time during which the electrostatic latent image can be formed, and the non-image portion static elimination lamp 5 is controlled to be turned off.

The predicted value is a value for synchronizing with the portion where the amount of light from the fall to the rise in the extinguishing to lighting of the exposure tamper 1a becomes lowest as shown in FIG.
The center of the extinguishing time of the exposure lamp 1a in the non-image portion is a value at which the minimum value of the exposure light amount reaches the non-uniform electric field. As a result, the portion where the light of the exposure lamp 1a is not irradiated during the exposure of the original and the non-image portion static elimination lamp 5 is turned off is developed with the toner by the developing device 3, and a toner band is formed.

In this manner, a toner band can be reliably formed in a place where the amount of light is low by only the timing signal for turning off the exposure stamp 1a, and a toner band having a predetermined width can always be created without using complicated control means. it can. In the same manner as described above, the light-on timing of the non-image portion static elimination lamp 5 is turned off according to the time of the predicted value from the turn-off timing signal of the exposure lamp 1a in the same manner as described above. It can be obtained by:

The second control means 9 synchronizes the center of the extinguishing time of the non-image portion static elimination lamp 5 with the portion where the amount of light from the rising to the falling of the light by the extinguishing and lighting of the exposure lamp 1a is reduced during multiple copying. Further, the third control means 10 controls the formation of an electrostatic latent image of a toner band on the image carrier 2 using the non-image portion discharging lamp 5 at the time of the backward scanning of the image exposure section 1, Fourth control means 12
Is created by developing the electrostatic latent image having a predetermined width formed by the third control means 10 by the developing device 3 under the control of the first control means 8 or the second control means 9. The cleaned toner band is cleaned by the cleaning device 4.

With the structure of this embodiment, the photosensitive drum 2
By cleaning the toner band formed on the non-image portion, the transfer paper component (deletion component) is removed together with the toner to eliminate the disturbance of the electrostatic latent image, and a high-quality copy can be obtained. FIG. 3 is a schematic diagram for explaining a configuration of a second embodiment of the image forming apparatus according to the present invention.
Reference numeral 3 denotes an exposure lamp history data storage unit for storing history data relating to usage conditions such as the usage time of the exposure stamp 1a and the number of times of turning on / off, and 14 denotes a time correction value set in advance corresponding to the history data of the exposure lamp. Correction value storage means to be stored, the same reference numerals as those in FIG. 1 correspond to the same parts.

In the present embodiment, the data of the exposure lamp history data storage means 13 refers to the correction data of the correction value storage means 14, and the second control means 9 is controlled by the reference data. This is for controlling the timing of turning off the lamp 5. According to this embodiment, it is possible to turn off the non-image portion static elimination lamp 5 at an optimum timing in accordance with a change in characteristics such as the amount of light of the exposure lamp 1a. To eliminate the disturbance of the electrostatic latent image and obtain a high quality copy.

FIG. 4 is a schematic view for explaining the structure of a third embodiment of the image forming apparatus according to the present invention.
A developing bias changing means 15 for changing the developing bias of the developing device 3 based on the timing of turning off the exposure lamp by the first control means 8. FIGS. 5A and 5B are operation timing charts for explaining the operation of the third embodiment of the present invention. FIG. 5A shows the on / off timing of the charger, FIG. c) shows the on / off timing of the exposure lamp, (d) shows the light amount level (relative value) of the exposure lamp, and (e) shows the development bias.

When the process speed of the image forming apparatus is increased, the extinguishing time of the exposure lamp 1a is shortened, and a sufficient toner bandwidth cannot be secured, so that it becomes difficult to supply a necessary amount of toner. In this embodiment, the developing bias is changed in a direction in which the toner is easy to ride in synchronization with the on / off of the exposure lamp 1a, so that a necessary amount of toner is secured on the photosensitive drum 2.

As shown at A in FIG. 5E, the developing bias of the developing device 3 of FIG. 4 is set based on the timing of turning off the exposure lamp by the first control means 8. To change. As a result, the amount of toner on the toner band portion increases, and a sufficient toner band can be created even when the process speed is high.

FIG. 6 is a schematic diagram for explaining the configuration of a fourth embodiment of the image forming apparatus according to the present invention. The image forming apparatus includes a toner band adjustment mode setting means 16 and the toner band adjustment mode setting means 16 controls the toner band adjustment. When the mode is set, the toner band width is changed by changing the extinguishing time of the non-image portion static elimination lamp 5. In other words, the toner band adjustment mode setting means 16 sets the toner band adjustment mode by a mode selection input from the user interface of the image forming apparatus, and the user changes the extinguishing time of the non-image portion static elimination lamp 5 using a numeric keypad or the like. Change the toner band width.

At this time, in order to visually confirm the toner band width, the toner band adjustment mode setting means 16 is used.
Then, a command to change the transport timing of the copy paper transport mechanism (not shown) and the timing of the scanning system of the exposure scanning unit 1 is output to convert the non-image portion into a hard copy. For example, a magnification of 100
The original is scanned at A4 size and the copying operation is executed at A3 size for copy paper. At this time, the registration timing of the original and the copy paper is set so that the leading ends thereof are substantially the same as in the normal copy mode, and the other conditions are the same as in the normal copy mode in which a toner band is created. By the operation, a toner band is created in a portion of A3 copy paper after the A4 size.

In this way, the toner band of the non-image portion is converted into a hard copy, and in the adjustment mode, the user (adjustment operator) rewrites the light-off time of the non-image portion static elimination lamp while viewing the hard copy to obtain a desired width. Can be formed. Next, an embodiment of the toner band forming method according to the present invention will be described. [First Embodiment of Toner Band Forming Method] Exposure Lamp 1a
An image exposure unit 1 having an optical scanning system 1b, an image carrier 2 on which an electrostatic latent image is formed by scanning of the image exposure unit, and a developing device 3 for developing the electrostatic latent image of the image carrier with toner. A cleaning device 4 of a blade type for cleaning the toner on the image carrier, a non-image-portion discharging lamp 5 for removing a non-image portion of the image carrier 2, and a uniform charging of the image carrier 2 The first embodiment of the toner band forming method in an image forming apparatus including at least an image forming unit including at least a charging device 6 that performs the following steps: (1) The image carrier 2 is uniformly charged by the charging device 6. Charging step, (2) turning off the non-image-portion discharging lamp 5 when the exposure lamp falls after a predetermined time in which an electrostatic latent image can be formed with reference to the timing of turning off the exposure lamp 1a during single-sheet copying. , For multiple copies (3) a toner band portion electrostatic charge remaining step of synchronizing the center of the non-image portion charge eliminating lamp 5 with the center of the extinguishing time to a portion having the lowest light amount from falling to rising by turning off and lighting of the light lamp 1a; A residual electrostatic charge developing step in which the developing device 3 develops the residual electrostatic charge width created in the first toner band electrostatic charge remaining step or the second toner band electrostatic charge remaining step; At least each step is included.

According to this embodiment, an accurate toner band can be created. [Second Embodiment of Toner Band Creation Method] Exposure Lamp 1a
An image exposure unit 1 having an optical scanning system 1b, an image carrier 2 on which an electrostatic latent image is formed by scanning of the image exposure unit, and a developing device 3 for developing the electrostatic latent image of the image carrier with toner. A cleaning device 4 of a blade type for cleaning the toner on the image carrier, a non-image-portion discharging lamp 5 for removing a non-image portion of the image carrier 2, and a uniform charging of the image carrier 2 The second embodiment of the method of forming a toner band in an image forming apparatus including at least an image forming unit having at least a charging device 6 for performing the operation and a toner band adjustment mode setting means 16 includes the following steps: Setting the toner band adjustment mode by the means 16; (2) charging the image carrier 2 uniformly with the charging device 6; and (3) turning off the exposure lamp 1a when copying a single sheet. When the exposure lamp falls after a predetermined period of time after which an electrostatic latent image can be formed with reference to the toner image, the non-image portion static elimination lamp 5 is turned off for a time based on an adjustment input from the toner band adjustment mode setting means 16. In the case of a plurality of copies, a toner band portion electrostatic charge that synchronizes the center of the non-image portion charge removing lamp 5 with the center of the non-image portion charge removing lamp 5 to a portion where the light amount falls from the fall to the rise due to the extinguishing and lighting of the exposure lamp 1a. (4) a transfer timing changing step for changing the paper feeding timing and the scanning timing of the image exposure unit 1 when the toner band adjustment mode is set by the toner band adjustment mode setting means 16; A residual electrostatic charge developing step of developing the residual electrostatic charge width created in the electric charge residual step by the developing device 3, (6) the image Comprising at least a toner band transferring the toner band formed lifting body on the sheet.

Through the above steps, the user or the adjusting operator can visually inspect the formation state of the toner band width as a hard copy, and can adjust the toner band width based on the inspection.

[0048]

As described above, according to the present invention,
Since the extinguishing of the non-image portion static elimination lamp is controlled based on the extinguishing lamp extinguishing timing, a predetermined toner band can be reliably formed with a simple configuration. Further, even if there is a change in the use condition of the exposure lamp, the extinguishing of the non-image portion charge eliminating lamp is controlled in accordance with the prediction control condition stored in advance, so that the extinguishing timing can always be optimally corrected.

Further, even when the speed of the image forming apparatus is increased, a necessary amount of toner can be supplied to the cleaning device. By making a hard copy of the toner band actually created, the creation state can be checked visually, so that it is possible to make sure adjustments.If the toner band has an adjustment mode capable of adjusting the width of the created toner band, it is necessary. The toner bandwidth can be changed according to

When the process speed is further increased, the required toner amount can be put on the image carrier by changing the developing bias in synchronization with the exposure lamp.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a configuration of a first embodiment of an image forming apparatus according to the present invention.

FIG. 2 is an operation timing chart for explaining the operation of the first embodiment of the image forming apparatus according to the present invention.

FIG. 3 is a schematic diagram illustrating the configuration of a second embodiment of the image forming apparatus according to the present invention.

FIG. 4 is a schematic diagram illustrating a configuration of a third embodiment of the image forming apparatus according to the present invention.

FIG. 5 is an operation timing chart for explaining the operation of the third embodiment of the present invention.

FIG. 6 is a schematic diagram illustrating a configuration of a fourth embodiment of the image forming apparatus according to the present invention.

FIG. 7 is a schematic diagram illustrating a configuration of a main part of a conventional image forming apparatus.

[Explanation of symbols]

Exposure lamp consisting of a fluorescent lamp or a halogen lamp which is turned on when moving forward during document scanning and turned off when returning, 1b ... An optical scanning system for guiding to the body drum 2, 2,...
A developing device that develops the electrostatic latent image formed on the photosensitive drum 2 with toner, and a photoconductor drum that is an image carrier that carries an electrostatic latent image and a toner-developed visual image.・
..Blade-type cleaning device for scraping off toner on the surface of photoreceptor drum 2, 5... Non-image portion charge eliminating lamp for erasing unnecessary charges and latent images before forming latent images, 6. ..A charger for uniformly charging the surface of the photosensitive drum 2 to a positive or negative polarity, 7... A static elimination lamp for removing residual charges on the photosensitive drum 2, 8.
... Predicted value storage means for storing a value obtained by previously measuring a predetermined time during which an electrostatic latent image can be formed by actual measurement as a predicted value, 9... Second control means, 10 ...
· Third control means, 12 ··· Fourth control means, 13
... Exposure lamp history data storage means for storing history data relating to usage conditions such as the usage time of the exposure stamp 1a and the number of times of turning on / off, 14... Preset in correspondence with the history data of the exposure lamp ... A developing bias changing means for changing a developing bias of the developing device 3; and a toner band adjustment mode setting means.

Claims (6)

(57) [Claims] 1. An image exposure section 1 having an exposure lamp 1a and an optical scanning system 1b, an image carrier 2 on which an electrostatic latent image is formed by optical scanning of the image exposure section, and an electrostatic latent image on the image carrier. The image forming apparatus includes at least a developing device 3 for developing an image with toner, a blade-type cleaning device 4 for cleaning toner on the image carrier, and a non-image-portion removing lamp 5 for removing charges from a non-image portion of the image carrier. An image forming apparatus comprising: an image forming unit, wherein the non-image area static elimination is performed when a light amount of the exposure lamp falls after a predetermined time period in which the formation of the electrostatic latent image is possible with reference to a timing of turning off the exposure lamp 1a. A first control means for turning off the lamp; and a non-image portion charge elimination run in a portion having the smallest light quantity from the rise to the fall due to the extinguishing and lighting of the exposure lamp during multiple copying. A second control means 9 for synchronizing the center of the extinguishing time of the image forming unit 5; A third control means 10 for controlling the formation of an electro-latent image, and a predetermined width formed by the third control means 10 under the control of the first control means 8 or the second control means 9 An image forming apparatus comprising: a fourth control unit for cleaning a toner band formed by developing an electrostatic latent image by the developing device with the cleaning device. 2. The exposure lamp 1a according to claim 1, wherein
Exposure lamp history data storage means 13 for storing a change in the use condition of the camera, and a correction value storage means 14 for storing a time correction value set in advance corresponding to the history data of the exposure lamp.
An image forming apparatus that controls the timing of turning off the non-image portion static elimination lamp 5 output from the first control unit 8 based on the correction value read from the correction value storage unit 14. . 3. A developing bias changing means according to claim 1, wherein said developing bias is changed by said developing device.
5. An image forming apparatus, comprising: a developing bias of the developing device based on a timing at which the first control unit switches off the exposure lamp. 4. The image forming apparatus according to claim 1, further comprising a toner band adjustment mode setting unit, wherein when the toner band adjustment mode is set by the toner band adjustment mode setting unit, the non-image portion static elimination lamp is turned off. An image forming apparatus, wherein the toner bandwidth is changed by changing the width. 5. An image exposure section 1 having an exposure lamp 1a and an optical scanning system 1b, an image carrier 2 on which an electrostatic latent image is formed by scanning of the image exposure section, and an electrostatic latent image on the image carrier. Developing device 3 for developing the toner on the toner, and blade type cleaning device 4 for cleaning the toner on the image carrier
And an image forming unit including at least a non-image-portion discharging lamp 5 for discharging the non-image portion of the image carrier 2 and a charging device 6 for uniformly charging the image carrier 2. A method of forming a toner band in a forming apparatus, comprising: a charging step of uniformly charging the image carrier 2 with the charging device 6; and an electrostatic latent image based on the timing of extinguishing the exposure lamp 1a during single-sheet copying. A first toner band portion electrostatic charge remaining step of extinguishing the non-image portion charge eliminating lamp 5 when the exposing lamp falls after a predetermined time after forming, and extinguishing and lighting of the exposing lamp 1a during multiple copying A second toner band portion electrostatic charge remaining step of synchronizing the center of the light-off time of the non-image portion charge removing lamp 5 with a portion having the lowest light amount from the fall of the light amount to the rise of the first toner cover; And a developing step of developing the remaining electrostatic charge width created in the second electrostatic band remaining step or the second toner band electrostatic charge remaining step by the developing device 3. And a toner band forming method in the image forming apparatus. 6. An image exposure section 1 having an exposure lamp 1a and an optical scanning system 1b, an image carrier 2 on which an electrostatic latent image is formed by scanning of the image exposure section, and an electrostatic latent image on the image carrier. Developing device 3 for developing the toner on the toner, and blade type cleaning device 4 for cleaning the toner on the image carrier
A non-image-portion discharging lamp 5 for discharging a non-image portion of the image carrier 2, a charging device 6 for uniformly charging the image carrier 2, and a toner band adjustment mode setting means 16 A toner band forming method for an image forming apparatus comprising: a toner band adjusting mode setting unit configured to set a toner band adjusting mode by the toner band adjusting mode setting unit; A charging step for uniformly charging the non-image area discharging lamp when the exposure lamp falls after a predetermined time after an electrostatic latent image can be formed with reference to the timing of extinguishing the exposure lamp 1a during single-sheet copying. A first toner band portion electrostatic charge remaining step of turning off the light for a time based on the adjustment input from the toner band adjustment mode setting means 16; A second toner band portion electrostatic charge remaining step of synchronizing the center of the non-image portion static elimination lamp 5 with the center of the non-image portion static elimination lamp 5 to a portion having the lowest light intensity from the fall to the rise due to the extinguishing and lighting of the exposure lamp 1a; A transfer timing changing step of changing a paper feeding timing and a scanning timing of the image exposure unit 1 when the toner band adjustment mode is set by the toner band adjustment mode setting means 16; and a first toner band part electrostatic charge remaining step. And a developing step of developing the remaining electrostatic charge width created in the second toner band portion electrostatic charge remaining step by the developing device 3, wherein the toner formed on the image carrier is And a toner band transferring step of transferring the band onto a sheet of paper. .