JPH04337765A - Image forming device - Google Patents

Abstract

PURPOSE:To accurately correct individual registration caused by the change of an ambient temperature accompanied with a main body setting position and the processing of image forming. CONSTITUTION:When desired registration correction information is inputted based on an image output state, a 1st control means (control circuit 43a) controls the actuation of correction means (actuators 27-29) so as to correct the deviation of registration between a photosensitive body and an optical scanning system. After the correction, a 2nd control means (control circuit 43a) corrects the registration corrected by the 1st control means based on temperature information outputted from a temperature detection means.

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 that is equipped with a plurality of image carriers and is capable of multiple-forming images formed on each image carrier on a recording medium.

0002

2. Description of the Related Art FIG. 7 is a schematic perspective view illustrating the structure of this type of image forming apparatus.

[0003] In this process, a laser beam emitted from a laser light source (not shown) is scanned in both directions by a rotating polygon mirror 103 rotating in the direction of arrow B in the figure, resulting in colors of cyan (C), magenta (M), and yellow (Y). ), black (BK), respectively, and scanning lines 102C, 102M, 1 that have passed through the fθ lenses (not shown) respectively correspond to black (BK).
Photosensitive drums 101C, 101M, 101Y, 101BK rotate in the direction of arrow A in the figure by 02Y, 102BK.
An image is formed on the transfer material 105, and multiple images are formed by multiple transfer onto a transfer material 105 that is conveyed in the direction of arrow X in the figure. Note that 13 is a transfer belt, and 31 is a transfer belt drive roller. 6C~8C, 6M~8M, 6Y~8
Y, 6BK to 8BK are scanning mirrors.

In an apparatus having a plurality of image forming stations as described above, images of different colors are sequentially transferred onto the same surface of the same transfer material 105, so that if the transferred image position at each image forming station deviates from the ideal position, For example, in the case of a multicolor image, this may result in a gap between images of different colors or overlapping, and in the case of a color image, this may appear as a difference in color tone, or in severe cases, a color shift, which can significantly reduce the quality of the image. It was deteriorating.

By the way, as shown in FIGS. 8(a) to 8(d), the types of positional deviation of the transferred image include positional deviation (top margin) in the scanning line writing direction (direction A in the figure).
(See (a) in Figure 8), positional deviation (left margin) in the scanning direction (direction B perpendicular to direction A in the figure) ((b) in Figure 8).
), diagonal tilt deviation (see (c) in Figure 8),
There are deviations due to magnification errors (see (d) in FIG. 8), and in reality, a superimposition of the above four types of deviations appears.

[0006]The main cause of the above image shift is shown in FIG.
The top margin shown in (a) of FIG. This is a deviation in the image writing timing, that is, the scanning start timing for one scanning line, and in the case of the tilt deviation in the diagonal direction shown in FIG. The angular deviation is caused by a magnification error shown in FIG. 8(d), which is due to a deviation in the scanning line length due to an error ΔL in the optical path length from the optical scanning optical system of each station to the photosensitive drum. Therefore, regarding the top margin and left margin, scanning lines 102C and 10
The amount of deviation is corrected by electrically adjusting the scanning timing of 2M, 102Y, and 102BK. And the magnification error deviation,
In order to prevent tilt deviation, among the folding mirrors located in the middle of the optical path of each station, a substantially V-shaped pair of mirrors 6 and 7, which are a pair of mirrors 6 and 7 at right angles, are fixed to the main body of the apparatus, as shown in FIG. The amount of deviation can be corrected by making independent adjustments in the direction of the arrow E and the direction of the arrow F, respectively.

As adjustment means for making these adjustments, actuators 27 to 29 such as linear step actuators equipped with a step motor as a drive source that moves linearly in a stepwise manner are provided. Here, the actuator 27 is moved approximately parallel to the direction of arrow E1 in FIG. 9 to shorten the optical path length up to the photosensitive drums 101C, 101M, 101Y, and 101BK, and drive the actuator 27 in the direction of arrow E2 in FIG. Accordingly, the optical path length can be adjusted to be long. In this way, by adjusting the optical path length, the scanning lines 102C and 102C having a predetermined spread angle can be
2M, 102Y, 102BK photosensitive drum 101C, 1
The length on the 01M, 101Y, 101BK surface is
For example, as shown in FIG. 10(a), the scanning line m0 can be changed to the scanning line m1.

Furthermore, by simultaneously driving the actuators 28 and 29 in the same direction, for example in the direction of arrow F2 in FIG. As a result, (
The scanning line m0 shown in b) can be moved in parallel to the position of the scanning line m2. In addition, the actuator 28
, 29, or when driving in opposite directions such as moving the actuator 28 in the direction of arrow F1 and the actuator 29 in the direction of arrow F2, The inclination angle of scanning line m0 can be changed like scanning line m3.

As described above, the mirror pairs 6 and 7, each of which has a pair of mirrors assembled at a substantially right angle, are used to form the optical path of the scanning lines 102C, 102M, 102Y, and 102BK from the scanning optical device to the photosensitive drums 101C, 101M, 101Y, and 101BK. By adjusting the position of the mirror pair 6, 7 with the actuator 27 or the actuators 28, 29, the optical path length or the scanning line 102C, 102M,
The scanning positions of 102Y and 102BK can be adjusted independently. That is, by moving the pair of mirrors 6 and 7 arranged in a V-shape in the E direction, the scanning lines 102C, 102M, 102Y, 102BK formed on the photosensitive drums 101C, 101M, 101Y, 101BK are
The scanning lines 102C, 102M,
Only the optical path lengths of 102Y and 102BK can be corrected, and by moving mirror pairs 6 and 7 in the F direction, scanning lines 102C, 102M, 102Y, and 102BK can be corrected.
without changing the optical path length of the photosensitive drums 101C, 10.
The imaging position and angle on 1M, 101Y, and 101BK can be corrected.

[0010] By using the method explained above, it is possible to match all of the magnification error deviation, tilt deviation, top margin, and left margin of the other three scanning lines with respect to the reference scanning line 102C. becomes.

[0011]

[Problem to be Solved by the Invention] However, it is difficult to install a device in which a high-quality image without color shift is obtained by performing the above adjustment at the time of device assembly under suitable conditions and installing it at the location of the user who will actually use it. In this case, the following (1) to (3)
The problem shown below occurs.

(1) Since the inclinations of the floor planes at the device manufacturing adjustment location and the installation location are different, deviations in the inclination of the scanning line occur due to slight or extreme differences in the degree of twist of the entire device, resulting in A shift in the top margin and left margin occurs due to the tilt shift.

(2) Because the environmental temperature of the device manufacturing and adjustment location is different from that of the installation location, the dimensions of the entire device change due to thermal expansion, etc., and the optical path length of the scanning line, the spacing between the photosensitive drums, etc. change, and as a result, Magnification error and top margin deviation occur.

(3) After the apparatus is installed, the temperature of the apparatus is repeatedly raised and cooled by repeatedly moving and stopping each station, resulting in changes in the overall dimensions of the apparatus. This causes a magnification error and a top margin shift, similar to (2) above.

Furthermore, the factors (1) to (3) above will be explained below with reference to FIG. 11 and the like.

FIG. 11 is a sectional view illustrating a schematic configuration of the image forming apparatus shown in FIG. 7.

As shown in this figure, the entire device is supported by four casters or feet 30. Therefore, as mentioned above, if the flatness of the floor differs between the time of device manufacturing adjustment and the location where the device is set up, the height of the floor contact portion of the casters or installation feet 30 will change, and the device casing will be affected by its own weight. It twists without being able to support it. When the housing is twisted, the shafts of the photosensitive drums 101C, 101M, 101Y, and 101BK, the transfer belt drive roller shaft 31, and the driven roller shaft 32 are twisted. Also, the amount of twisting can be determined by using the casters or the installation foot 3.
It is not constant depending on the distance from 0. In such a state, the tilt deviation of the four scanning lines, top margin deviation, and left margin deviation described in the problem (1) above occur.

Furthermore, as the temperature of various parts within the apparatus rises as the apparatus is used, the diameter of the transfer belt drive roller 31 increases in accordance with the linear expansion coefficient and diameter of the material and the amount of temperature rise. Since the transfer belt drive roller 31 rotates at a constant angular velocity, the moving speed v of the transfer belt 13 increases by Δv. In other words, the transfer belt 13 moves at v+Δv. In this case, the top margin changes as shown in FIG. 12.

FIG. 12 shows the photosensitive drum 10 shown in FIG.
1C, 101M, 101Y, 101BK and a main part sectional view showing image transfer position deviations. FIG.

As shown in this figure, a photosensitive drum 10
1C, 101M, 101Y, and 101BK are arranged at regular intervals. In this case, if the moving speed of the transfer belt 13 is the normal moving speed, each image of the other station should overlap with the position C where the image is transferred to the transfer material 105 on the photosensitive drum 101C.
Since the speed of the transfer belt 13 is fast, the photosensitive drum 101M
In this case, the image is transferred to position M, which is later than position C. Similarly, photosensitive drums 101Y, 101BK
The Y and BK images at , as shown, are also transferred to the delayed positions Y and BK. In other words, a top margin shift at the lag level (plus level) occurs. Next, as the temperature of each part of the apparatus rises as the apparatus is used, the position of the side plate supporting the photosensitive drum shaft changes as shown in FIG. 13 in accordance with the linear expansion coefficient and dimensions of the material and the amount of temperature rise.

FIG. 13 shows the photosensitive drum 10 shown in FIG.
1C, 101M, 101Y, 101BK and a main part sectional view showing image transfer position deviations. FIG.

As shown in this figure, as the temperature of each part of the device rises as the device is used, the position of the side plate supporting the photosensitive drum shaft also changes depending on the linear expansion coefficient and dimensions of the material and the amount of temperature rise. For example, considering the photosensitive drum 101C as a reference,
The amount of position change (ΔL, 2ΔL, 3ΔL) increases in the order of photosensitive drums 101M, 101Y, and 101BK. In this case, since the transfer material 105 moves at a constant speed v, the transferred image is transferred to the transfer positions M, Y, and the position C.
BK is advanced, and as a result, a top margin shift of the advanced level (minus level) occurs.

On the other hand, when the side plate of the casing thermally expands as described above, the position of the reflecting mirror supported by the side plate also changes as shown in FIG.
Changes as shown in .

FIGS. 14 and 15 are sectional views of main parts showing the photosensitive drums 101C, 101M, 101Y, and 101BK shown in FIG. 11 and image transfer position deviations.

As shown in this figure, when the side plate of the device housing thermally expands in the same manner as described above, for example, in the x direction (paper conveyance direction), for example, considering the photosensitive drum 101C as a reference,
As the mirror positions of all stations change, the optical path length changes. Note that the amount of change is based on the photosensitive drum 10.
It is determined by the distance from 1C and is not constant.

Further, when the side plate of the device housing thermally expands as described above, for example, when the position changes in the y direction, the position of the mirror changes, so the optical path length and each photosensitive drum 101C change.
, 101M, 101Y, and 101BK change, resulting in a top margin shift.

[0027] The above description has been made regarding the case of temperature rise, but a similar phenomenon occurs in the opposite direction to the above when cooling is performed. As described above, in conventional equipment, magnification deviations, top margin deviations, left margin deviations, etc. occur depending on the installation environment of the main unit (due to the installation location). There was a problem in that internal temperature rises and falls, which inevitably caused tilt deviations and top margin deviations.

The present invention has been made to solve the above-mentioned problems, and by making it possible to correct the registration based on registration correction information, changes in the environmental temperature caused by the installation position of the main body and the execution of image forming processing can be avoided. An object of the present invention is to provide an image forming apparatus capable of outputting a clear, high-quality image without color shift while accurately correcting individual registrations caused by the above.

[0029]

[Means for Solving the Problems] An image forming apparatus according to the present invention includes a displaceable optical scanning system that scans and exposes a photoconductor with an optical signal modulated based on output information, and a displaceable optical scanning system that scans and exposes a photoreceptor to an optical signal that is modulated based on output information. a correction means for correcting the registration by controlling the displacement or the modulation timing of the output information;
a first control means for controlling the movement of the correction means based on registration correction information; a temperature detection means for detecting the environmental temperature around the photoreceptor; and a temperature detection means at the time when the registration correction by the first control means is completed. and second control means for correcting the registration corrected by the correction means based on temperature information output from the control means.

Further, an operating means is provided for manually instructing correction information including the correction amount of the correction means.

Furthermore, a prohibition means is provided for prohibiting registration correction processing by the first or second control means during a predetermined image forming process.

The first control means is configured to control the direction and amount of movement of the correction means based on input predetermined registration correction information to correct the magnification deviation between the optical scanning system and the photoreceptor. This is what I did.

Furthermore, the first control means is configured to control the movable direction and amount of movement of the correction means based on input predetermined registration correction information to correct tilt deviation between the optical scanning system and the photoreceptor. This is what I did.

Further, the first control means controls the movable direction and the amount of movement of the correction means based on input predetermined registration correction information to correct the top margin deviation between the optical scanning system and the photoreceptor. It is composed of

Furthermore, the first control means controls the movable direction and amount of movement of the correction means based on input predetermined registration correction information to correct left margin deviation between the optical scanning system and the photoreceptor. It is composed of

[0036] Furthermore, the apparatus is constructed such that a plurality of photoreceptors are provided, and the latent image formed on each photoreceptor can be developed using a different color developer.

[0037]

In the present invention, the first control means controls the correction means based on registration correction information based on the image output state to correct misregistration between the photoreceptor and the optical scanning system. After this correction, the second control means controls the first control means based on the temperature information output from the temperature detection means.
The registration corrected by the control means is further corrected to correct registration deviations caused by environmental temperature fluctuations associated with use of the apparatus, thereby making it possible to adjust the registration between the photoreceptor and the optical scanning system.

Furthermore, by manually inputting information including the amount of correction, it is possible to correct the registration caused by the environment in which the main body is grounded.

Further, the prohibition means prohibits the registration correction processing by the first or second control means during a predetermined image forming process, thereby making it possible to maintain the registration characteristics constant.

Further, the first control means controls the movable direction and amount of movement of the correction means based on predetermined registration correction information inputted, corrects the magnification deviation between the optical scanning system and the photoreceptor, and corrects the magnification deviation. This makes it possible to form images without

Furthermore, the first control means controls the movable direction and the amount of movement of the correction means based on input predetermined registration correction information, corrects the tilt deviation between the optical scanning system and the photoreceptor, and corrects the tilt deviation. This makes it possible to form images without

The first control means also controls the movable direction and amount of movement of the correction means based on input predetermined registration correction information to correct the top margin deviation between the optical scanning system and the photoreceptor, and correct the top margin deviation between the optical scanning system and the photoreceptor. It is possible to form an image without margin deviation.

Further, the first control means controls the movable direction and amount of movement of the correction means based on input predetermined registration correction information to correct the left margin deviation between the optical scanning system and the photoreceptor, and corrects the left margin deviation between the optical scanning system and the photoreceptor. It is possible to form an image without margin deviation.

Further, a plurality of photoreceptors are provided, and the latent image formed on each photoreceptor is visualized using a different color developer, thereby making it possible to form a clear color image without color shift.

[0045]

Embodiment FIGS. 1 and 2 are a block diagram and detailed block diagram illustrating a control configuration of an image forming apparatus showing an embodiment of the present invention, and the same parts as in FIG. 7 are denoted by the same reference numerals. be.

In these figures, reference numeral 1 denotes an operation unit through which specifications such as a pulse motor, a driving direction of this pulse motor, the number of driving pulses, a left margin, a top margin, etc., which serve as registration alignment information, are input. 2 is a temperature sensor that constantly monitors the temperature status of each part of the device while the power is turned on, and controls the control circuit section 4.
In step 3, information on temperature rise and fall associated with actual operation is sent.

The control circuit section 43 has a control circuit 43a equipped with a CPU, etc., and drives pulse motors 43b to 43k, which serve as correction means for performing registration correction, individually from the operation section 1 according to the output image result. Based on each relative positional deviation amount Δl with respect to the specified input reference station (relative positional deviation amount ΔlCM between cyan and magenta, relative positional deviation amount ΔlCY between cyan and yellow, relative positional deviation amount ΔlCBK between cyan and black). control. Note that each relative positional deviation amount with respect to the reference station is obtained from the image output result as shown in FIG.

Reference numeral 41 denotes a laser driver for generating laser light, and a solid-state laser element 42 as a laser light source connected to this laser driver 41 blinks in response to a light emission signal thereof. The laser beam emitted from this laser light source is scanned onto the photosensitive drum 101 by the rotating polygon mirror 103 via the folding mirrors 6 to 8, as described above. A pulse motor 43 f for adjusting the magnification error of the V-shaped folding mirror pair 6 and 7 is connected to the control circuit section 43 . The temperature sensor 2 is connected to the control circuit section 43 . 44 is an image processing section, which is connected to the laser driver 41 and the control circuit section 43.

In the image forming apparatus configured as described above, the image output state is visually checked by the user or the service technician who sets the image, and desired registration correction information is inputted from, for example, the operation unit 1 based on the state at that time. Then, the first control means (in this embodiment, the control circuit 43a) controls the movement of the correction means (actuators 27 to 29 provided corresponding to each photosensitive drum), so that the photoreceptor and the optical scanning system (
In this embodiment, misregistration with mirror pairs 6, 7, etc.) is corrected. After this correction, the second control means (control circuit 43a in this embodiment) further corrects the registration corrected by the first control means based on the temperature information output from the temperature detection means (temperature sensor 2). This makes it possible to relatively correct registration deviations caused by the setting environment of the device itself and registration deviations caused by environmental temperature fluctuations associated with device use, and to correct the registration of the photoreceptor and optical scanning system. do. In addition,
Regarding the first control means, not only correction by manual instruction but also automatic control by automatic registration mark detection is possible.

Furthermore, by manually inputting information including the amount of correction, it is possible to correct the registration caused by the environment in which the main body is grounded.

Furthermore, the inhibiting means (control circuit 43a in this embodiment) inhibits the registration correction process by the first or second controlling means during a predetermined image forming process,
It is possible to maintain constant registration characteristics.

Further, the first control means controls the movable direction and amount of movement of the correction means based on predetermined registration correction information inputted, corrects the magnification deviation between the optical scanning system and the photoreceptor, and corrects the magnification deviation. This makes it possible to form images without

Furthermore, the first control means controls the movable direction and amount of movement of the correction means based on input predetermined registration correction information to correct the tilt deviation between the optical scanning system and the photoreceptor. This makes it possible to form images without

Further, the first control means controls the movable direction and amount of movement of the correction means based on inputted predetermined registration correction information, corrects the top margin deviation between the optical scanning system and the photoreceptor, and corrects the top margin deviation between the optical scanning system and the photoreceptor. It is possible to form an image without margin deviation.

Furthermore, the first control means controls the movable direction and amount of movement of the correction means based on input predetermined registration correction information to correct the left margin deviation between the optical scanning system and the photoreceptor, and It is possible to form an image without margin deviation.

Further, a plurality of photoreceptors are provided, and the latent image formed on each photoreceptor is visualized using a different color developer, thereby making it possible to form a clear color image without color shift. In addition, the above first
, the second control means, and the prohibition means in this embodiment, the control circuit 4
Although the configuration is such that the unit 3a serves as both, each unit may be configured with independent hardware.

FIG. 3 is a flowchart showing an example of the registration correction processing procedure in the image forming apparatus according to the present invention. Note that (1) to (16) indicate each step.

Using the reference scanning line as cyan C, an image is formed on the transfer material using the scanning line so that the cyan station and the magenta station match, and a fixed image is output (1
). Then, a registration alignment process (steps (21) to (27)), which will be described later, is executed (2).

Next, in the same manner as described above, using the reference scanning line as cyan C, a scanning line is formed on the transfer material 105 so that the cyan station and the magenta station match, and a fixed image is output. It is determined whether the register and the register match (3), and if NO, steps (1) to (3) are repeated.

This process is similarly executed for the relationship between the cyan station and the yellow station, and the relationship between the cyan station and the black station (4).
~(9) After all the resists match the cyan station serving as the reference station, resist correction processing based on usage environment temperature fluctuations (details will be described later)
(10), and the process ends.

The registration process in this embodiment will be explained with reference to FIG.

FIG. 4 is a schematic diagram illustrating the registration process in the image forming apparatus according to the present invention. PPP1~
PPP5 is a sheet of paper (transfer paper) that serves as a transfer material, and registration correction detection patterns PATC and PATM formed at each station are sequentially specified to detect each positional deviation element (tilt deviation, magnification deviation, left margin deviation). , top margin deviation, etc.) are corrected.

For example, as shown in FIG. 4(a), paper PP
If P1 is output, it can be determined that the tilt, magnification, left margin, and top margin are all shifted. Therefore, information for correcting the inclination deviation obtained by visually observing the distance difference Δl1 shown in FIG. The number of driving pulses of the pulse motor thus determined is input from the operation unit 1. In response to this input, the control circuit 43a controls the drive of the pulse motor 43f, and individually drives the actuators 29 and 28, which can move the mirror pairs 6M and 7M up and down a specified amount, to adjust the inclination. In this state, the registration correction detection patterns PATC and PATM are outputted onto the transfer paper PPP2 in the same manner as described above.

The registration correction detection patterns PATC (specified by the line segments CL and CR) and PATM (specified by the line segments ML and MR) on the transfer paper PPP2 are the registration correction detection patterns PATC (specified by the line segments ML and MR).
It can be visually observed that the magnifications of the image and the registration correction detection pattern PATM are deviated.

Therefore, registration correction detection patterns PATC (specified by line segments CL and CR), P
Information for visually obtaining the relative length difference Δl2 of ATM (specified by line segments ML and MR) from the transfer paper PPP2 and correcting the magnification deviation, a pulse motor for correcting the relative length difference Δl2, and the like. The correction direction and the number of drive pulses of the designated pulse motor are input from the operation unit 1. In this state, registration correction detection patterns PATC and PATM are outputted onto the transfer paper PPP3 in the same manner as described above.

The registration correction detection patterns PATC (specified by the line segments CL and CR) and PATM (specified by the line segments ML and MR) on the transfer paper PPP3 are the registration correction detection patterns PATC (specified by the line segments ML and MR).
It is visually observed that the left margin is shifted between the left margin and the registration correction detection pattern PATM.

Therefore, registration correction detection patterns PATC (specified by line segments CL and CR), P
Information for visually obtaining the left margin difference Δl3 of ATM (specified by line segments ML and MR) from the transfer paper PPP3 and correcting the left margin deviation, a pulse motor for correcting the margin difference Δl3, and its correction direction. , the number of drive pulses for the specified pulse motor is input from the operation unit 1. In this state, registration correction detection patterns PATC and PATM are outputted onto the transfer paper PPP4 in the same manner as described above.

The registration correction detection patterns PATC (specified by line segments CL and CR) and PATM (specified by line segments ML and MR) on this transfer paper PPP4 are the registration correction detection patterns PATC (specified by line segments ML and MR).
It can be visually observed that the top margins of the pattern and the registration correction detection pattern PATM are shifted.

Therefore, registration correction detection patterns PATC (specified by line segments CL and CR), P
Information for visually obtaining the relative top margin difference Δl4 of ATM (specified by line segments ML and MR) from the transfer paper PPP4 and correcting the top margin deviation, a pulse motor for correcting the margin difference Δl4, and its correction. The direction and number of drive pulses for the designated pulse motor are input from the operation unit 1. In this state, registration correction detection patterns PATC and PATM are outputted onto the transfer paper PPP5 in the same manner as described above. As a result, the resists of the cyan station and the magenta station substantially match. Similarly, for the cyan station, yellow station, cyan station, and black station, the registration correction amount is obtained visually from the pattern output state output on the paper, and the drive of the corresponding pulse motor is controlled from the operation unit 1. , the registration states of all stations can be made to substantially match the cyan station, which is the reference station. As a result, even if the adjustment has been made in the factory shipment state, it is possible to adjust the positional color shift due to the twisting of the casing, etc. that occurs due to the environmental condition in which the device is installed, and it is possible to obtain high-quality color images thereafter.

Next, automatic temperature correction processing will be explained.

As described above, the temperature of the apparatus increases due to the temperature of the environment in which the apparatus is installed and the heat generated inside the apparatus, causing a magnification error deviation and a top margin deviation. Here, as shown in FIG. 5, data on the magnification error deviation amount Δl2 and top margin deviation amount Δl4 are experimentally collected with respect to the temperature increase amount ΔT.

[0072] Here, the experimental range of the temperature increase amount ΔT may be determined by the sum of the maximum value of the calorific value during use of the apparatus, the upper limit value of the environmental temperature in which the apparatus can be used, and the lower limit value of the environmental temperature in which the apparatus can be used. If the temperature detection sensor is set at a fixed location near the transfer belt drive roller 31 or folding mirrors 6 and 7, which cause magnification errors and top margin errors,
A correlation between the magnification error deviation Δl2, the top margin deviation Δl4, and the temperature change amount ΔT can be obtained. The relationship between the temperature change amount, the magnification error correction amount, and the top margin correction amount is obtained from the relationship between the temperature change amount, the magnification error deviation, and the top margin deviation amount obtained as described above. Based on the correction amount obtained in this way, the relationship between the number of V-shaped mirror drive pulses and the top margin write timing change amount is obtained.

[0073] Then, the temperature detected by the temperature detection sensor at the time of register registration at the time of device installation and at the time of inputting the automatic temperature correction start signal (see step (10) shown in FIG. 3) and the temperature at the time of use of the device is determined. The above-mentioned magnification error deviation and top margin deviation are corrected based on the difference. Although the above explanation has been made with reference to the time when the device is installed, the present invention is not limited to that time. Even more effects can be expected if it is carried out when a problem occurs.

A case in which execution of the registration correction function processing is prohibited will be described below with reference to FIG.

When forming a desired image, first, an image output signal P is inputted from the image processing section 44 to the control circuit section 43, and an image signal S is inputted to the laser driver 41, and the solid-state laser element is activated at a predetermined timing. 42 blinks. The laser beam emitted from the laser light source is scanned by the rotating polygon mirror 103, and an exposure distribution for one scan of the image is formed on the surface of the photosensitive drum 101. Furthermore, the photosensitive drum 101 is rotated by a predetermined amount for each scan. A latent image having an exposure distribution according to the image signal S is formed on the photosensitive drum 101, and is recorded as a visible image on recording paper by a well-known electrophotographic process. The image output signal P is output from the image processing section 44 before the image signal S, and the output ends after the output of the image signal S ends. Further, the control circuit unit 43 stops operating while the image output signal P is input from the image processing unit 44.

Therefore, the temperature signal T from the temperature sensor 2 is not input during the image forming operation (details of the image forming operation in this embodiment will be described later). Further, a magnification error correction signal Q and a top margin correction signal R are sent to pulse motors 43b, 43d, and 4 for requesting magnification, respectively.
Since there is no output to 3f or 43h, the scanning line magnification and top margin can be kept constant, and high-quality images with no color shift or color change can be obtained on a single sheet of recording paper. .

Note that during the image forming operation in this embodiment (
(during image formation) refers to the period during which a light source is modulated according to the image signal S to form a unitary image that becomes a scanning surface, and one scanning line and The above-mentioned one unit does not refer to the period during which the light source is not modulated during one scanning line, but refers to the period in which the light source is not modulated.
), it refers to image information for one sheet of recording paper or multiple sheets of recording paper (as long as there are two or more sheets, the same applies to any number of sheets).
As shown in (c), it does not refer to the intervals between each scanning line of one sheet of recording paper.

[0078]

As explained above, the present invention provides a displaceable optical scanning system that scans and exposes a photoreceptor with an optical signal that is modulated based on output information, and a displaceable optical scanning system that scans and exposes a photoreceptor to an optical signal that is modulated based on output information. a first correction means for controlling the modulation timing of the output information to correct the registration; and a first correction means for controlling the movement of the correction means based on the registration correction information.
a temperature detection means for detecting the environmental temperature around the photoreceptor; and a registration corrected by the correction means based on temperature information output from the temperature detection means at the time when registration correction by the first control means is completed. Since the second control means for correcting the registration is provided, even if the registration deviates depending on the environmental condition of the device, the registration can be adjusted to match the device environment.

Furthermore, since an operating means is provided for manually instructing correction information including the correction amount of the correction means, correction information including the correction amount can be input manually, and registration deviations when the main body is installed can be easily corrected. Can be done.

Furthermore, since a prohibition means is provided for prohibiting the registration correction processing by the first or second control means during a predetermined image forming process, it is possible to prevent misregistration from occurring due to environmental temperature changes accompanying the execution of the image forming process. Even if the registration error is corrected, it can be corrected individually according to the input registration deviation correction information.

The first control means is configured to control the direction and amount of movement of the correction means based on input predetermined registration correction information to correct the magnification deviation between the optical scanning system and the photoreceptor. Therefore, image formation can be continued while the registration state is kept constant, and image deterioration due to registration correction can be prevented.

Furthermore, the first control means is configured to control the movable direction and amount of movement of the correction means based on input predetermined registration correction information to correct the tilt deviation between the optical scanning system and the photoreceptor. Therefore, even if a tilt shift occurs due to a change in the environmental temperature due to the installation position of the main body or the execution of the image forming process, the tilt shift can be corrected individually according to the input registration shift correction information.

Further, the first control means controls the movable direction and amount of movement of the correction means based on predetermined input registration correction information to correct the top margin deviation between the optical scanning system and the photoreceptor. With this configuration, even if a top margin shift occurs due to a change in the environmental temperature due to the installation position of the main body or the execution of image forming processing, the top margin shift can be corrected individually according to the input registration shift correction information.

Furthermore, the first control means controls the movable direction and amount of movement of the correction means based on input predetermined registration correction information to correct left margin deviation between the optical scanning system and the photoreceptor. With this configuration, even if a left margin shift occurs due to a change in the environmental temperature due to the installation position of the main body and the execution of image forming processing, the left margin shift can be corrected individually according to the input registration shift correction information.

In addition, since a plurality of photoreceptors are provided and the latent image formed on each photoreceptor can be developed using a different color developer, images of each color can be overlapped without color shift. It is possible to form high-quality images without distortion.

Therefore, even if individual registration deviations occur based on the usage environment in which the main body of the apparatus is set, registration correction can be easily performed regardless of the setting environment or usage environment, and the registration deviations can be corrected. This has the advantage that it is possible to always provide high-quality images without any blemishes.

[Brief explanation of drawings]

FIG. 1 is a block diagram illustrating a control configuration of an image forming apparatus showing an embodiment of the present invention.

FIG. 2 is a detailed block diagram illustrating a control configuration of an image forming apparatus according to an embodiment of the present invention.

FIG. 3 is a flowchart showing an example of a registration correction processing procedure in the image forming apparatus according to the present invention.

FIG. 4 is a schematic diagram illustrating the registration process in the image forming apparatus according to the present invention.

FIG. 5 is a characteristic diagram showing the relative relationship between misregistration and environmental temperature in the image forming apparatus according to the present invention.

FIG. 6 is a schematic diagram showing an image processing unit in the image forming apparatus according to the present invention.

FIG. 7 is a schematic perspective view illustrating the configuration of this type of image forming apparatus.

FIG. 8 is a schematic diagram illustrating misregistration in this type of image forming apparatus.

FIG. 9 is a perspective view showing a registration deviation correction mechanism in this type of image forming apparatus.

FIG. 10 is a diagram illustrating registration shift correction processing in this type of image forming apparatus.

11 is a sectional view of the image forming apparatus shown in FIG. 7. FIG.

FIG. 12 is a cross-sectional view of a main part showing the relative relationship between registration deviation factors and output images in this type of image forming apparatus.

FIG. 13 is a cross-sectional view of a main part showing the relative relationship between registration deviation factors and output images in this type of image forming apparatus.

FIG. 14 is a cross-sectional view of a main part showing the relative relationship between registration deviation factors and output images in this type of image forming apparatus.

FIG. 15 is a cross-sectional view of a main part showing the relative relationship between registration deviation factors and output images in this type of image forming apparatus.

[Explanation of symbols]

1　　　　　　　Operation section 2 Temperature sensor 43 Control circuit section 43a Pulse motor 43b Pulse motor 43c pulse motor 43d Pulse motor 43e Pulse motor 43f pulse motor 43g pulse motor 43h pulse motor 43i pulse motor 43j Pulse motor 43k pulse motor

Claims (8)

[Claims] 1. A displaceable optical scanning system that scans and exposes a photoconductor with an optical signal modulated based on output information, and a displaceable optical scanning system that is configured to displace the optical scanning system in a predetermined direction or control the modulation timing of the output information. a correction means for correcting registration; a first control means for controlling movement of the correction means based on registration correction information; a temperature detection means for detecting an environmental temperature around the photoreceptor; and a second control means for correcting the registration corrected by the correction means based on the temperature information output from the temperature detection means at the time when the registration correction by the control means is completed. Device. 2. The image forming apparatus according to claim 1, further comprising operation means for manually instructing correction information including the correction amount of the correction means. 3. The image forming apparatus according to claim 1, further comprising prohibition means for prohibiting registration correction processing by the first or second control means during a predetermined image forming process.
The image forming apparatus according to any one of the above. 4. The first control means corrects the magnification deviation between the optical scanning system and the photoreceptor by controlling the movable direction and the amount of movement of the correction means based on predetermined input registration correction information. The image forming apparatus according to claim 1 or 2. 5. The first control means corrects the tilt deviation between the optical scanning system and the photoreceptor by controlling the movable direction and the amount of movement of the correction means based on input predetermined registration correction information. The image forming apparatus according to claim 1 or 2. 6. The first control means corrects a top margin misalignment between the optical scanning system and the photoreceptor by controlling the movable direction and the amount of movement of the correction means based on input predetermined registration correction information. The image forming apparatus according to claim 1 or 2. 7. The first control means corrects a left margin misalignment between the optical scanning system and the photoreceptor by controlling the movable direction and the amount of movement of the correction means based on input predetermined registration correction information. The image forming apparatus according to claim 1 or 2. 8. The image forming apparatus according to claim 1, wherein the image forming apparatus includes a plurality of photoreceptors, and the latent image formed on each photoreceptor can be developed using a different color developer. .