JP3530626B2 - Image forming apparatus and registration correction method for image forming apparatus - 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 and image having a plurality of scanning optical systems and having a function of automatically correcting an image shift caused by the scanning optical systems when forming images on a recording medium in a multiplex manner. The present invention relates to a registration correction method for a forming apparatus.

[0002]

2. Description of the Related Art FIG. 7 is a perspective view for explaining the structure of the main part of this type of image forming apparatus.

In FIG. 7, a laser beam emitted from a laser light source (not shown) is bidirectionally scanned by a rotary polygon mirror 103 which rotates in the direction of arrow B in the figure, and cyan (C), magenta (M) and yellow ( Fθ lens (not shown) corresponding to Y) and black (BK) respectively
Scanning line 102C passing through the fθ lens,
102Y, 102Y, 102BK indicate arrow A'in the figure
Photoconductor drums 101C, 101M, 10 rotating in the direction
An image is formed on 1Y and 101BK by a known electrophotographic process, and is transferred in the arrow X'direction in the drawing.
By performing multiple transfer on No. 05, multiple images are formed. Incidentally, 113 is a transfer belt, and 114 is a transfer belt drive roller. 106C ~ 108C, 106M ~ 1
08M, 106Y to 108Y, 106BK to 108BK
Is a reflection mirror.

In such an apparatus having a plurality of image forming stations, since images of different colors are sequentially transferred onto the same surface of the same transfer material 105, the transfer image position in each image forming station is changed from the ideal reference position. For example, in the case of a multi-color image, image gaps or overlaps of different colors may occur, and in the case of a color image, a difference in color tint may occur, and when the degree is severe, a color shift may appear. The quality was significantly deteriorated.

By the way, as the types of positional deviation of the transferred image, as shown in FIGS. 8A, 8B, 8C, and 8D, the scanning line writing direction (X1 'direction in the drawing). Position deviation (top margin) (FIG. 8A), position deviation (left margin) in the scanning direction (B ′ direction orthogonal to the X1 ′ direction in the drawing) (FIG. 8B), diagonal direction There are tilt shifts ((c) in FIG. 8), magnification shifts ((d) in FIG. 8), etc. In reality, the above four types of shifts are superimposed.

The main cause of the image shift is shown in FIG.
In the case of the top margin shown in (a) of FIG. 8, it is the deviation of the image writing timing of each image forming station (hereinafter, simply referred to as a station), and in the case of the left margin of FIG. In the case of an image writing timing, that is, a deviation of the scanning start timing in one scanning line, and in the case of the inclination deviation in the oblique direction of FIG. 8C, the attachment angle deviation of the scanning optical system or the rotation axis of the photosensitive drum 8D, the magnification deviation of FIG. 8D is due to the scanning line length deviation due to the error in the optical path length from the optical scanning optical system of each station to the photosensitive drum.

Therefore, regarding the top margin and the left margin, the scanning lines 102C, 102M, 102Y, 10
The amount of deviation is corrected by electrically adjusting the scanning timing of 2BK.

As to the deviation of magnification and the deviation of inclination, as shown in FIG. 9, of the folding mirrors in the optical path of each station, for example, a pair of mirrors 206 and 207 are arranged in a right angle and have a substantially C-shape. The mirror pair 200 is independently adjusted with respect to the apparatus main body in the arrow E'direction and the arrow F'direction, respectively, so that the respective shift amounts can be corrected.

Actuators 27 and 28 such as a linear step actuator having a step motor, which is a drive source for linearly moving in stages, are provided as adjusting means for performing these adjustments.

The mirrors 206 and 207 are mirror holders 2.
The mirror holder 231 is supported by 31 and the swing plate 232
With respect to the mirrors 206, 2 by moving the pressing portion 234 in the F ′ direction by the actuator 28 supported by the three fulcrums 232a, 232b, 232c and supported by the oscillating plate 232.
07 is rotated around the fulcrum 232a. Swing plate 232
Is supported by fixed points 232d and 232e with respect to the fixed plate 233 fixed to the apparatus main body, and the actuator 27 supported by the fixed plate 233 moves the pressing portion 235 in the E ′ direction to move the mirrors 206 and 207 to the fulcrum points 232d and 232d. 232e
Rotate around.

Here, in order to correct the tilt deviation in FIG. 8C, the actuator 28 is used as shown in FIG. 9C.
This can be done by driving the and shifting the tilt positions of the front and back of the mirrors 206 and 207.

To correct the magnification deviation shown in FIG. 8D,
By driving the actuator 27 to rotate the mirrors 206 and 207 including the swing plate 232 as shown in FIG. 9B, the optical path length to the photosensitive drum of the optical scanning optical system is changed. It will be possible.

As described above, the mirrors 206 and 207 in which a pair of mirrors are installed at a substantially right angle are provided in the scanning optical device to the photosensitive drums 101C, 101M, 101Y and 101B.
Scan lines up to K 102C, 102M, 102Y, 102
The optical path length or the scanning line 102 is arranged by adjusting the positions of the pair of mirrors 206 and 207 by the actuator 27 or the actuator 28 by disposing them in the optical path of BK.
The tilts in the scanning direction of C, 102M, 102Y, and 102BK can be adjusted independently.

That is, by moving the mirror pair 200 provided with a pair of mirror-shaped mirrors 206 and 207 in the E'direction, the photoconductor drums 101C and 101C are moved.
Scanning line 102 formed on M, 101Y, 101BK
Without changing the positions of C, 102M, 102Y, 102BK, the scanning lines 102C, 102M, 102Y, 102
Only the optical path length of BK, that is, the magnification shift can be corrected, and the scanning lines 102C, 102M, 102 can be moved by moving the pair of mirrors 206, 207 in the F'direction.
It is possible to correct the image forming position and angle on the photoconductor drums 101C, 101M, 101Y and 101BK without changing the optical path lengths of Y and 102BK. The above-mentioned various means for reading the positional deviation will be described.

In FIG. 7, 315 and 316 are transfer materials 1.
05 or a register mark transferred onto the transfer belt 113, 313 and 314 are sensors (usually CCD) for reading the register mark, 309 and 31
Reference numeral 0 is an optical system for reading with a sensor. An assembly of the respective optical systems is the LSR and LSF.

In such a configuration, the positional deviation of the image caused by the various factors described above is read by the sensor (CCD) 313, 314 of the register mark transferred to the transfer belt 113 or the transfer material 105, and is obtained therefrom. Various positional deviations are calculated from the signals and the deviations are corrected by the method described above. A flow chart for misalignment correction is shown in FIG.

FIG. 10 is a flowchart showing an example of a registration correction processing procedure in this type of image forming apparatus. Note that (1) to (8) indicate each step.

First, a registration mark is formed at each station (1), each registration mark transferred to the transfer belt is read by the sensor units LSR and LSF (2), and each registration deviation amount is calculated (3). A correction amount for correcting the registration of each station is calculated (4), the tilt deviation is corrected by the actuator 28 (5), the magnification deviation is mechanically corrected by the actuator 27 (6), and each of the laser beams L1 to L1. The scanning timing of L4 is changed to electrically correct the top margin and the left margin (7), (8).

[0019]

However, when the amount of color misregistration that causes a difference in tint of an image exceeds 150 μm,
Since the image becomes unbearable, the deviation is adjusted to 150 μm or less.

Further, considering the recent trend toward higher image quality, it is necessary to set the deviation correction target to about 120 μm. That is, since the current 150 μm is changed to 120 μm, it is necessary to improve the accuracy by 30 μm.

As described in the figure, when the actuator 28 is driven to correct the tilt shift, the tilt of the image is designed to move "2" when the actuator 28 is moved "1".

In FIG. 9, when the actuator 28 is moved by the correction amount, the pressing portion 23 of the mirror holder 231 is moved.
Press 4 by a predetermined amount. Mirror holder 231 is spring 25
Since the oscillating plate 232 is urged by the actuators 1 and 252, and the actuator 28 is urged by a spring (not shown), the actuator 28 resists the force and the mirror holder 23.
You need to move 1.

Further, since the mirror holder 231 and the holding member (not shown) for holding the actuator 28 are made of a metal or a resin material, the actuator 28 is surely formed no matter how rigid the shape is. Elastic deformation occurs due to the pressing force of.

That is, as described above, 100 μm on the image
When performing the displacement correction, the actuator is moved by 50 μm, which is ½ of the displacement. However, if the elastic deformation of each part is about 15 μm, the mirror holder 231 actually moves only 35 μm, and it moves only 70 μm, which is twice that on the image, that is, a correction error of 100−70 = 30 μm occurs. This 30 μm error is the boundary between the color misregistration amount of 150 μm or 120 μm and greatly affects the image quality.

Furthermore, the amount of elastic deformation is unstable because it depends on the frictional force of various parts of the machine part, so it is difficult to predict the amount in advance, and the same applies to magnification correction. is there.

[0026] The present invention has been made to solve the above problems, the present onset bright object, before registration correction processing start in each image forming station, by moving disposed an optical scanning system resist By trial-driving the drive mechanism for correcting the registration deviation, the mechanical rattling and distortion of the optical scanning system are removed before the registration deviation correction, and even if unexpected elastic deformation of mechanical parts occurs, accurate An object of the present invention is to provide an image forming apparatus capable of performing registration deviation correction and a registration correction method for the image forming apparatus.

[0027]

A first aspect of the present invention is a latent image forming means for forming a latent image by scanning a photoconductor with a modulated laser beam by an optical scanning system, and the photoconductor. In an image forming apparatus in which image forming stations each having a developing unit that visualizes the latent image formed above with a developer are juxtaposed for the number of developing colors, a conveying unit that conveys a transfer material and each image forming station are formed. Detecting means for detecting a predetermined image transferred to the conveying means, and adjusting means for moving the optical scanning system in a predetermined direction to adjust the arrangement position,
A correcting unit that drives the adjusting unit based on the detection result of the detecting unit to mechanically correct the registration of each image forming station; and the adjusting unit before the predetermined image formation by the image forming station. A control means for unconditionally performing trial drive is provided.

According to a second aspect of the present invention, the control means trial drives the adjusting means so as to move the optical scanning system back and forth in the predetermined direction by the same amount.

In a third aspect of the present invention, the control means trial drives the adjusting means so as to vertically move the optical scanning system by the same amount in a predetermined direction.

A fourth invention according to the present invention is the adjusting means.
Is an actuator. According to the present invention
The invention of No. 5 is such that a photosensitive member is optically moved by a modulated laser beam.
A latent image forming means for forming a latent image by scanning with a scanning system;
Visualize the latent image formed on the photoreceptor with a developer
Image forming stations equipped with developing means
In the placed image forming apparatus, a carrier for transferring the transfer material
And the transfer means formed at each image forming station
Detecting means for detecting a predetermined transferred image;
Adjustment to move the scanning system in the specified direction and adjust the placement position
Means and the adjusting hand based on the detection result of the detecting means.
Registration of each imaging station by driving the steps
Correction means for mechanically correcting the image, and the image forming station
Before the prescribed image formation by the
Both equipped with a control means for performing trial drive once or more
Is. According to a sixth aspect of the present invention, the control means is
Move the optical scanning system up and down or back and forth in the same direction in a predetermined direction.
Adjust the adjustment hand so that it can be moved in either direction without
This is a test drive of the stage. Seventh invention according to the present invention
Is equipped with a clocking means for clocking the stopped state of the image forming apparatus.
The control means is responsive to the timing result of the timing means.
And change the number of times the trial drive of the adjusting means is performed.
is there. An eighth aspect of the present invention provides a humidity sensor,
The control means, according to the output of the humidity sensor,
The number of times of trial drive of the adjusting means is changed. Book
In a ninth aspect according to the invention, the adjusting means is an actuator.
Data. A tenth invention according to the present invention is
Optical scanning system on the photoconductor by modulated laser light
A latent image forming means for forming a latent image by scanning;
Developing means for visualizing the latent image formed on the surface with a developer
Image forming stations equipped with
Formed and transferred by several imaging stations
Image forming apparatus including a transport belt that transports each image
At the plurality of imaging stations
Detecting means for detecting a predetermined image transferred on the belt
And move the optical scanning system in a predetermined direction to change the arrangement position.
Adjusting means for adjusting, and based on the detection result of the detecting means
Drive the adjusting means to register the image forming stations.
Correction means for mechanically correcting the tralation, and the image formation
The adjustment before the predetermined image formation by the station
And a control means to drive the means at least once.
It is equipped. The eleventh invention according to the present invention is
The control means moves the optical scanning system up and down by the same amount in a predetermined direction.
Or move it in at least one of the front and back directions
As described above, the adjusting means is trial-driven. In the present invention
According to a twelfth aspect of the present invention, the stop state of the image forming apparatus is timed.
And a control means for controlling the time of the time measuring means.
Depending on the time result, the number of times of trial drive of the adjusting means is changed.
It is something to be improved. A thirteenth invention according to the present invention is humidity
A sensor is provided, and the control unit outputs the humidity sensor.
The number of times the trial drive of the adjusting means is changed according to
It is a thing. A fourteenth invention according to the present invention is a latent image forming means for forming a latent image by scanning the photoconductor with a modulated laser beam by an optical scanning system, and developing the latent image formed on the photoconductor. An image forming station provided with a developing unit that visualizes with a developer is juxtaposed for the number of developing colors, and a conveying unit that conveys a transfer material, and a predetermined image formed at each image forming station and transferred to the conveying unit. Of the image forming stations, the adjusting means for moving the optical scanning system in a predetermined direction to adjust the arrangement position, and the adjusting means driven based on the detection result of the detecting means. In the registration correction method of the image forming apparatus, the adjustment means is unconditionally trial-driven before the predetermined image formation by the image forming station. To those having a driving process.

[0031]

[0032]

[0033]

[0034]

[0035]

1 is a schematic perspective view for explaining the structure of an image forming apparatus showing an embodiment of the present invention.

In the figure, laser beams L1 to L4 emitted from a laser light source (not shown) are bidirectionally scanned by a rotary polygon mirror 103 rotating in the direction of arrow B in the figure to produce cyan (C), magenta (M), The scanning line 102 that has passed through the fθ lenses (not shown) corresponding to yellow (Y) and black (BK), respectively, and has passed through the fθ lenses.
The photosensitive drums 101C, 101M, 10 which rotate in the direction of arrow A in the figure by C, 102M, 102Y, 102BK.
An image is formed on the 1Y and 101BK, and a multiple image is formed by performing multiple transfer on the transfer material 105 conveyed in the arrow X direction in the drawing.

Reference numeral 113 is a transfer belt, and 114 is a transfer belt driving roller. 106C to 108C, 106
M ~ 108M, 106Y ~ 108Y, 106BK ~ 10
8BK is a reflection mirror (mirror).

CONT is a controller unit, and CPU, R
It is equipped with an AM and a ROM, and controls the image forming process, registration correction and the like as a whole. The controller unit CONT controls driving of the actuators 27 to 28 via the motor driver MD, and
The emission of the laser beams L1 to L4 for each color modulated based on the image signal is controlled via the laser driver LD.

FIG. 2 is a schematic perspective view of a main part for explaining a resist correction mechanism in the laser scanning system of the image forming apparatus shown in FIG. 1. The same parts as those in FIG. 1 are designated by the same reference numerals. .

Regarding the top margin left margin, the deviation amount is corrected by electrically adjusting the scanning timing of the scanning lines 102C, 102M, 102Y and 102BK. As for the magnification error shift and the tilt shift, as shown in FIG. 2, among the folding mirrors in the optical path of each station, the mirrors 6 and 7 are paired at a right angle to form a substantially C-shaped mirror pair, as shown in FIG. The amount of deviation can be corrected by adjusting the direction of arrow E and the direction of arrow F independently with respect to the apparatus body.

Actuators 27 to 29 such as linear step actuators having a step motor, which is a drive source for linearly moving in stages, are provided as adjusting means for performing these adjustments. Here, the actuator 27 is moved substantially parallel to the arrow E ₁ direction in FIG. 2 to shorten the optical path length onto the photosensitive drums 101C, 101M, 101Y and 101BK, and the actuator 27 is driven in the arrow E ₂ direction in FIG. As a result, the optical path length can be adjusted longer.

Correspondence between this embodiment and each means of the first to third inventions and their functions will be described below with reference to FIGS.

A first invention is a latent image forming means (reflection mirrors 106C, 107C, 108) for forming a latent image by scanning an optical scanning system on a photoconductor with modulated laser light.
C, 106M, 107M, 108M, 106Y, 107
Y, 108Y, 106BK, 107BK, 108BK)
And the photoconductors 101C, 101M, 101Y, 101
In the image forming apparatus, in which image forming stations including developing means for developing a latent image formed on BK) with a developer are arranged side by side for the number of development colors, a conveying means (transfer belt 113) for conveying the transfer material and Detecting means (sensors 313, 314) for detecting a predetermined image formed at each image forming station and transferred to the conveying means, and adjusting means for moving the optical scanning system in a predetermined direction to adjust the arrangement position. (Actuators 27 to 29), a correction unit (by the CPU of the controller unit CONT) that mechanically corrects the registration of each image forming station by driving the adjustment unit based on the detection result of the detection unit, Before the predetermined image formation by the image forming station, the control means (triggered by the CPU of the controller unit CONT to unconditionally test drive the adjustment means) That) are provided on a substrate, sensor 313,3
Before forming the predetermined image (registration mark) by each image forming station for mechanically correcting the registration of each image forming station by driving the actuators 27 to 29 based on the detection result of 14, the controller unit CONT Allows the actuators 27 to 29 to be unconditionally tested to remove the play and distortion of the optical scanning system adjusted by the adjusting means.

In a second aspect of the invention, the control means (by the CPU of the controller CONT) drives the adjusting means (actuators 28, 29) in a trial direction so as to move the optical scanning system back and forth by the same amount in the predetermined direction. It is possible to remove backlash and distortion without shifting the arrangement of the optical scanning system before and after driving (directions of arrows E ₁ and E ₂ ).

In a third aspect of the present invention, the control means (by the CPU of the controller CONT) drives the adjusting means (actuator 27) so as to move the optical scanning system up and down in the predetermined direction by the same amount. It is possible to remove backlash and distortion without shifting the top and bottom (arrows F ₁ and F ₂ directions) of the optical scanning system before and after driving.

The registration correction preprocessing in the image forming apparatus according to the present invention will be described below with reference to the flow charts shown in FIGS.

FIG. 3 is a flow chart showing an embodiment of the registration correction preprocessing method of the image forming apparatus according to the present invention. Note that (1) to (10) indicate each step.

When the deviation correction operation is turned on, first, the aging processing routine of the actuators 27 to 29 is executed (1) and (2). By this processing operation, it is possible to remove the backlash of the mechanical part and remove the strain caused by the elastic deformation of various parts of the mechanical part.

Immediately after that, a resist mark is formed, and the deviation correction operation is performed in the same manner as in the conventional case (3) to (10). At this time, the actuators 27 to 29 are operated again, but since the backlash / distortion is removed by the aging operation described above, it is possible to perform a predetermined deviation correction.

Next, referring to FIG. 4, the actuator 27
The aging operations of 29 to 29 will be described. Since the actuators 27 to 29 are similar, the actuator 28 will be described as an example here.

FIG. 4 shows the actuator 27 shown in FIG.
30 is a flowchart showing a detailed procedure of a first aging processing routine of Nos. 29 to 29. Note that (1) to (3) indicate each step.

First, the drive pulse P1 (CW direction) is output from the controller unit CONT to the actuator 28 via the motor driver MD, is fed out by 200 μm (1), and the pressing portion 234 of the mirror holder 231 is pressed.

Next, the controller unit CONT outputs a drive pulse P2 (CCW direction) to the actuator 28 via the motor driver MD to pull in 400 μm (2), and further, to the actuator 28 from the controller unit CONT. The drive pulse P1 (CW direction) is output via the motor driver MD and is fed out by 200 μm (3), and the aging process is ended. This allows
Pre-driving eliminates the effects of backlash and distortion of the mirror holder.

Further, since the amount of extension and retraction is the same, the mirror holder 231 is returned to the same position as at the beginning, so that even if the registration mark is written in this state, it can be out of the optical effective range of the reading systems LSR and LSF. There is no.

Further, even if there is a difference between the amount of extension and the amount of drawing in, the deviation amount of the registration mark after reading only increases, and the deviation is corrected from that state.
No problem.

FIG. 5 shows the actuator 27 shown in FIG.
30 is a flowchart showing a detailed procedure of a second aging processing routine of Nos. 29 to 29. Note that (1) and (2) indicate each step.

First, the drive pulse P3 (CCW direction) is output from the controller unit CONT to the actuator 28 via the motor driver MD and pulled in by 200 μm (1), and the controller unit CONT sends the motor driver MD to the actuator 28. The drive pulse P4 (in the CW direction) is output via 200 μm to 200 μm (2), and the aging process ends. As a result, the pre-driving eliminates the influence of backlash and distortion of the mirror holder and the like.

FIG. 6 shows the actuator 27 shown in FIG.
30 is a flowchart showing a detailed procedure of a third aging processing routine of Nos. 29 to 29. Note that (1) and (2) indicate each step.

First, the drive pulse P4 (CW direction) is output from the controller unit CONT to the actuator 28 via the motor driver MD and is fed 200 μm (1), and the controller unit CONT outputs the drive pulse P4 (CW direction) to the actuator 28 from the motor driver MD. Drive pulse P via
3 (CCW direction) is output and 200 μm is pulled in (2), and the aging process is completed. As a result, the pre-driving eliminates the influence of backlash and distortion of the mirror holder and the like.

Correspondence between the present embodiment and each step of the fourth invention and its action will be described below with reference to FIGS.

In a fourth aspect of the invention, latent image forming means (reflection mirrors 106C, 107C and 108) for forming a latent image by scanning the photosensitive member with an optical scanning system by means of modulated laser light.
C, 106M, 107M, 108M, 106Y, 107
Y, 108Y, 106BK, 107BK, 108BK)
And the photoconductors 101C, 101M, 101Y, 101
In the image forming apparatus, in which image forming stations including developing means for developing a latent image formed on BK) with a developer are arranged side by side for the number of development colors, a conveying means (transfer belt 113) for conveying the transfer material and Detecting means (sensors 313, 314) for detecting a predetermined image formed at each image forming station and transferred to the conveying means, and adjusting means for moving the optical scanning system in a predetermined direction to adjust the arrangement position. (Actuators 27 to 29) and a correction unit (by the CPU of the controller unit CONT) that drives the adjustment unit based on the detection result of the detection unit to mechanically correct the registration of each image forming station. In the registration correction method for an image forming apparatus, the adjusting means is unconditionally operated before the predetermined image formation by the image forming station. Was driven to drive step (step of FIG. 3 (1), (2)) makes it possible to automate running, the process would eliminate the backlash and distortion of an optical scanning system which is regulated by the regulating means.

In the above embodiment, when the deviation correction is performed,
This is a sequence that is executed each time as a preliminary operation before this correction, but when the device is left in a stopped state for a long period of time, the frictional force of the contact part between machine parts increases and the deformation strain increases. There is a case. In such a case,
By repeating the aging treatment operation shown in (1) several times instead of once, the deformation strain can be reduced, and the same effect can be obtained. The stopped state of the machine can be judged by measuring the time with an internal timer.

When the power outlet is unplugged,
If the above sequence is executed at the time of the first deviation correction after turning on the power, it is possible to cope with a long-term neglect.

Even in a high humidity environment, the frictional force may increase due to the influence of water, and the deformation strain may increase. Even in such a case, the same effect can be obtained by repeating the aging operation several times. It is possible to know whether the high humidity environment is distorted by the humidity sensor provided in the device.

Further, in the above embodiment, the actuator 2
Although the case where the mirror holder is corrected upward by 8 and 29 has been described, the present invention can be applied to the case where the actuator 28 is corrected upward.

[0066]

As described above, the first aspect of the present invention
According to the invention, the correction means for driving the adjusting means on the basis of the detection result of the detection means to mechanically correct the registration of each image forming station before the predetermined image formation by each image forming station. In addition, since the control means unconditionally trial-drives the adjusting means, it is possible to remove rattling and distortion of the optical scanning system adjusted by the adjusting means.

According to the second aspect of the present invention, the control means trial-drives the adjusting means so as to move the optical scanning system forward and backward in the predetermined direction by the same amount. Therefore, the front and rear positions of the optical scanning system are displaced before and after the trial driving. You can remove rattling and distortion without any effort.

According to the third aspect of the invention, the control means performs the test drive of the adjusting means so as to vertically move the optical scanning system by the same amount in the predetermined direction. It is possible to remove backlash and distortion without deviating.

According to the fourth invention, the adjusting means is
Since it is a actuator, it can be adjusted by an actuator.
It may remove backlash and distortion of the optical scanning system
it can. According to the fifth invention, based on the detection result of the detection means.
Drive the adjusting means based on
Each work for the correction means to mechanically correct the tralation
Before the prescribed image formation by the image station,
Since the step drives the adjusting means at least once,
Removes play and distortion of the optical scanning system that is adjusted by the adjusting means.
Can be removed. According to the sixth invention,
The control means moves the optical scanning system up or down in the same direction by the same amount or in front.
Adjust to move in at least one direction after
Since the means is test driven, the optical scanning system
Remove backlash and distortion without shifting the top and bottom or front and back
Can be removed. According to the seventh invention, the image
Controlling by providing timing means for timing the stopped state of the image forming apparatus
The means has an adjusting means in accordance with the timing result of the timing means.
The number of trial drives is changed, so the device can be used for a long period of time.
If you increase the number if you leave it in a stopped state
Rattling or distortion of the optical scanning system adjusted by some adjusting means
Can also be removed. According to the eighth invention, the humidity sensor
Sensor, and the control means responds to the output of the humidity sensor.
Change the number of times the trial drive of the adjustment means
Adjustment by means of adjustment that may increase in
It also eliminates rattling and distortion of the optical scanning system.
It According to the ninth invention, the adjusting means is an actuator.
And so the optical scanning adjusted by the actuator
It can remove rattling and distortion of the system. First
According to the invention of No. 0, it adjusts based on the detection result of the detection means.
The registration means of each image forming station by driving the means.
The image forming station is provided for the correction means for mechanically correcting the image
Before the predetermined image formation by the
Since the adjustment means is driven at least once,
Removes rattling and distortion of the optical scanning system adjusted by the node means.
You can get rid of it. According to the eleventh invention,
The control means moves the optical scanning system up or down in the same direction by the same amount or in front.
Said to move in at least one direction after
Since the adjustment means is driven by trial, optical scanning is performed before and after trial drive.
Rattling and distortion without shifting the top and bottom or front and back of the system
Can be removed. According to the twelfth invention
For example, a time-measuring means for timing the stopped state of the image forming apparatus is installed.
The control means adjusts the time in accordance with the timing result of the timing means.
Since the number of times of trial drive of the node means is changed, the device can be used for a long time.
Increases when left in a stopped state for a while
The optical scanning system may be adjusted by some adjusting means.
Data and distortion can also be removed. According to the thirteenth invention
For example, a humidity sensor is provided, and the control means controls the humidity sensor.
Depending on the output, change the number of trial drive of the adjusting means
Therefore, the temperature may increase in a high humidity environment.
Also eliminates backlash and distortion in the optical scanning system that is adjusted by the node means.
Can be excluded. According to the fourteenth aspect , since the adjusting unit is unconditionally driven for trial before the predetermined image formation by the image forming station, the process of removing the play and distortion of the optical scanning system adjusted by the adjusting unit. Can be automated.

Therefore, even if an unexpected elastic deformation of the mechanical component occurs, the registration deviation can be accurately corrected.

[Brief description of drawings]

FIG. 1 is a schematic perspective view illustrating a configuration of an image forming apparatus according to an exemplary embodiment of the present invention.

2 is a schematic perspective view of a main part for explaining a registration correction mechanism in a laser scanning system of the image forming apparatus shown in FIG.

FIG. 3 is a flowchart showing an embodiment of a registration correction preprocessing method of the image forming apparatus according to the present invention.

4 is a flowchart showing a detailed procedure of a first aging processing routine of the actuator shown in FIG.

5 is a flowchart showing a detailed procedure of a second aging processing routine of the actuator shown in FIG.

6 is a flowchart showing a detailed procedure of a third aging processing routine of the actuator shown in FIG.

FIG. 7 is a perspective view illustrating a main configuration of an image forming apparatus of this type.

FIG. 8 is a schematic diagram illustrating the types of registration deviation of this type of image forming apparatus.

9 is a diagram illustrating a mechanical registration correction mechanism of the optical scanning system shown in FIG.

FIG. 10 is a flowchart showing an example of a registration correction processing procedure in this type of image forming apparatus.

[Explanation of symbols]

27 Actuator 28 actuators 29 Actuator CONT controller section

Front page continuation (58) Fields surveyed (Int.Cl. ⁷ , DB name) B41J 2/44 G02B 26/10

Claims (14)

(57) [Claims] 1. A latent image forming means for forming a latent image by scanning a photoreceptor with an optical scanning system by a modulated laser beam, and a latent image formed on the photoreceptor is visualized by a developer. In an image forming apparatus in which image forming stations each including a developing unit that is arranged for the number of developing colors are arranged, a conveying unit that conveys a transfer material and a predetermined image formed at each image forming station and transferred to the conveying unit are detected. Detecting means, adjusting means for moving the optical scanning system in a predetermined direction to adjust the arrangement position, and driving the adjusting means based on the detection result of the detecting means to perform registration of each image forming station. Correction means for correcting the image, and before the predetermined image formation by the image forming station,
An image forming apparatus characterized by including a control means for trying driven the adjustment means unconditionally. 2. The image forming apparatus according to claim 1, wherein the control means trial-drives the adjusting means so as to move the optical scanning system back and forth in the predetermined direction by the same amount. 3. The image forming apparatus according to claim 1, wherein the control unit trial-drives the adjustment unit so as to vertically move the optical scanning system by the same amount in a predetermined direction. 4. The adjusting means is an actuator
The image forming apparatus according to claim 1, wherein: 5. Light on the photoconductor by the modulated laser light
Image forming means for forming a latent image by scanning with an optical scanning system
And the latent image formed on the photoconductor is visualized with a developer.
The number of developing colors
In the image forming apparatus juxtaposed with each other, Transporting means for transporting the transfer material, Formed at each image forming station and transferred to the transport means.
Detection means for detecting a predetermined image Adjust the placement position by moving the optical scanning system in a predetermined direction
Adjusting means, Driving the adjusting means based on the detection result of the detecting means
The mechanical registration of each imaging station.
Correction means for correcting to Before the predetermined image formation by the image forming station,
Control for trial driving the adjusting means at least once
Means and An image forming apparatus comprising: 6. The control means sets the optical scanning system to a predetermined value.
The same amount up and down, or at least one of the front and back
Trial driving the adjusting means to move it in the direction
The image forming apparatus according to claim 5, wherein 7. Timekeeping that measures the stopped state of the image forming apparatus
Means The control means, according to the timing result of the timing means,
It is characterized in that the number of times of trial driving the adjusting means is changed.
The image forming apparatus according to claim 6. 8. A humidity sensor is provided, and the control means is
Trial drive of the adjusting means according to the output of the humidity sensor
7. The image according to claim 6, wherein the number of times to perform is changed.
Image forming device. 9. The adjusting means is an actuator
The image forming apparatus according to claim 6, wherein 10. With the modulated laser beam,
Latent image forming means for forming a latent image by scanning with an optical scanning system
And the latent image formed on the photoconductor is visualized with a developer.
The number of developing colors
Side-by-side with each other by the multiple imaging stations
Equipped with a conveyor belt that conveys each formed and transferred image
In the image forming device On the conveyor belt by the plurality of imaging stations
Detection means for detecting the transferred predetermined image, Adjust the placement position by moving the optical scanning system in a predetermined direction
Adjusting means, Driving the adjusting means based on the detection result of the detecting means
The mechanical registration of each imaging station.
Correction means for correcting to Before the predetermined image formation by the image forming station,
Control for trial driving the adjusting means at least once
Means and An image forming apparatus comprising: 11. The control means controls the optical scanning system.
At least one of the same amount up and down or front and back in a fixed direction
Test drive the adjusting means to move in the direction
The image forming apparatus according to claim 10, wherein: 12. The method according to claim 12, A clock that counts the stopped state of the image forming apparatus
Time means, The control means, according to the timing result of the timing means,
It is characterized in that the number of times of trial driving the adjusting means is changed.
The image forming apparatus according to claim 11. 13. A humidity sensor is installed, The control means, according to the output of the humidity sensor,
Characterized in that the number of times of trial driving of the adjusting means is changed.
The image forming apparatus according to claim 11, further comprising: 14. A latent image forming means for forming a latent image by scanning an optical scanning system on a photoconductor with modulated laser light, and a latent image formed on the photoconductor is visualized by a developer. Image forming stations each having a developing unit for paralleling the number of developing colors, and further, a conveying unit for conveying a transfer material, and a detecting unit for detecting a predetermined image formed at each image forming station and transferred to the conveying unit. And adjusting means for adjusting the arrangement position by moving the optical scanning system in a predetermined direction, and mechanically correcting the registration of each image forming station by driving the adjusting means based on the detection result of the detecting means. A registration correction method for an image forming apparatus, comprising: a correction unit for performing the predetermined image formation by the image forming station,
A registration correction method for an image forming apparatus, comprising a driving step of unconditionally trial-driving the adjusting means.