JP2004029675A - Image forming apparatus, control method for the image forming apparatus, control program for the image forming apparatus, and storage medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus, a control method for the image forming apparatus, a control program for the image forming apparatus, and a storage medium for minimizing color slurring by adjusting the phase of an image carrier without increasing a user's down time nor the consumption of a toner etc. <P>SOLUTION: An optimum phase result determined by adjusting the rotary phase of a photoreceptor drum (image carrier) 1 is stored in a memory and if a phase shift quantity measured value based upon the last adjustment result stored in the memory is within a prescribed range when the rotary phase of the photoreceptor drum 1 is adjusted, the rotary phase adjustment is ended while the last phase is regarded as an optimum phase as it is, but if not, a motor control part 54 performs control for making rotary phase adjustments with phases at all angles according to the last phase adjustment result. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention stores an image forming apparatus such as a color copying machine, a color printer (for example, a laser beam printer, an LED printer, etc.), a facsimile apparatus and a word processor, a control method for the image forming apparatus, a control program for the image forming apparatus, and a storage medium for storing the control program. To a storage medium.
[0002]
[Prior art]
In an image forming apparatus using electrophotography, if the image forming apparatus is used for a long time, the image carrier (photosensitive drum) is replaced, the developer is replenished or replaced, and adjustment (cleaning, cleaning, etc.) of other components (e.g., a charger and a cleaner container) is performed. Although replacement is required, such maintenance work has been virtually difficult except for service technicians with specialized knowledge.
[0003]
Therefore, in an image forming apparatus using an electrophotographic image forming process, the electrophotographic photosensitive member and the process means acting on the electrophotographic photosensitive member are integrally made into a cartridge, and this cartridge is detachable from the image forming apparatus main body. A process cartridge system is adopted. According to this process cartridge system, the maintenance of the apparatus can be performed by the user himself without relying on a service person, so that the operability can be remarkably improved. Therefore, this process cartridge system is widely used in image forming apparatuses.
[0004]
Here, the electrophotographic image forming apparatus forms an image on a recording medium using an electrophotographic image forming method. Examples of the electrophotographic image forming apparatus include, for example, an electrophotographic copying machine, an electrophotographic printer (for example, a laser beam printer, an LED printer, and the like), a facsimile machine, a word processor, and the like.
[0005]
The above-described process cartridge system refers to a system in which a charging unit, a developing unit, or a cleaning unit and an electrophotographic photosensitive member are integrally formed into a cartridge, and the cartridge is detachable from an image forming apparatus main body. .
[0006]
Further, the above-mentioned process cartridge system means that at least one of a charging unit, a developing unit, and a cleaning unit and an electrophotographic photosensitive member are integrally formed into a cartridge, and the cartridge is detachably mountable to an electrophotographic image forming apparatus main body. Say
[0007]
Further, the above-mentioned process cartridge system refers to a system in which at least the developing means and the electrophotographic photosensitive member are integrally formed into a cartridge, and this cartridge is detachably mountable to the main body of the electrophotographic image forming apparatus.
[0008]
Conventionally, there is a color image forming apparatus called a so-called in-line system in which a plurality of photosensitive drums are arranged in a line. This is because while the transfer material is carried and conveyed by an electrostatic transfer belt stretched by a plurality of rollers, yellow, magenta, cyan, and black are provided by four photosensitive drums arranged along the transfer material conveyance path. Are sequentially transferred onto a transfer material, and a color image is formed by superimposing each color. This configuration has attracted attention in recent years because it can print at high speed.
[0009]
However, since each color is formed by four photosensitive drums, a configuration in which colors are superimposed on one photosensitive drum via four transport buses for each color (hereinafter, simply referred to as a “four-pass method”) ), Higher accuracy is required for the rotational drive of the photosensitive drum. Further, in this type of apparatus, the image forming mechanism is unitized, becomes a process cartridge, and is configured to be detachable from the image forming apparatus main body, so that maintenance can be easily performed.
[0010]
In general, a drive gear train is used to drive the photosensitive drum, and low-frequency rotation unevenness such as one rotation component of the gear always occurs. However, in the case of the four-pass system, the reduction ratio of the drive gear train is reduced. By using a combination of integers, it is possible to avoid the accumulated pitch error of the gears and to adjust the image forming position of each color.
[0011]
However, in the case of the in-line method, since the plurality of photosensitive drums are independent, the drive gear train is also independent, and it is difficult to avoid the above-described four-pass method, and the image forming position of each color is shifted. Image quality deterioration such as color shift is likely to occur.
[0012]
Therefore, conventionally, as a countermeasure against color misregistration, the angular speed of the photosensitive drum is detected, the image transferred to the transfer material is read to detect the speed unevenness, and the rotation of the motor is canceled so as to cancel the speed unevenness. As disclosed in JP-A-9-146329 and JP-A-10-333398, the relative color misregistration is achieved by adjusting the rotational phase of each photosensitive drum to a desired state. Measures have been taken to reduce this.
[0013]
By the way, conventionally, a color image forming apparatus and an image quality adjustment system capable of greatly reducing color misregistration by a method of easily detecting angular velocity unevenness of a photosensitive drum and adjusting a rotation phase of each photosensitive drum have been taken. I have.
[0014]
In this case, in order to adjust the rotation phase of each photoconductor drum to a desired state, an image transferred to a transfer material of the photoconductor drum is read, and a detection method of detecting angular velocity unevenness uses a method of detecting the phase of each photoconductor drum. There is a photoconductor drum phase adjustment method that determines the optimum phase for color misregistration by controlling and detecting speed unevenness corresponding to the phase of the photoconductor drum.
[0015]
[Problems to be solved by the invention]
However, in the above-described conventional photoconductor drum phase adjustment method, measurement is performed on all phases in accordance with the resolution at which the drum phase can be controlled. Therefore, measurement time is required for all phases, and a long time is required until the adjustment is completed. This is necessary and there is a disadvantage that downtime for the user increases. Further, performing the phase measurement for all the phases has a disadvantage in that the consumption of toner and the like increases to form an image necessary for the phase measurement.
[0016]
SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems of the related art, and has as its object to execute the phase adjustment of the image carrier without increasing the downtime of the user and the consumption of toner and the like. In addition, it is an object of the present invention to provide an image forming apparatus, a control method of the image forming apparatus, a control program of the image forming apparatus, and a storage medium which can minimize color misregistration.
[0017]
[Means for Solving the Problems]
In order to achieve the above object, an image forming apparatus according to the present invention stores an optimum phase result determined by adjusting a rotational phase of an image carrier corresponding to a plurality of colors in a memory, and adjusts a rotational phase of the image carrier. At this time, if the measured value of the positional deviation amount due to the previous adjustment result phase stored in the memory is within the specified range, the rotation phase adjustment is terminated with the previous phase as the optimum phase, and the rotation phase is out of the specified range. In this case, a control means is provided that controls the rotational phase adjustment to be performed at all the phases from the previous phase adjustment result.
Further, in order to achieve the above object, the image forming apparatus of the present invention has a phase adjustment unit that adjusts the rotation phase of the image carrier corresponding to a plurality of colors, and can simultaneously detect a reference color and a detection color. A misregistration detecting means for calculating a misregistration amount of the detected color with respect to the reference color from a detection result of the detection pattern arranged in the detection pattern; an amplitude of the misregistration amount detected by the misregistration detecting means and detection angle information; An optimal phase detecting means for detecting a rotation phase in which the amplitude is minimized as an optimal phase of the image carrier based on the reference, and a reference for each image carrier determined based on a detection result of the optimal phase detecting means. Storage means for storing an optimum phase for a color, and a rotational phase of the image carrier fixed to an optimum phase which is a previous optimum phase detection result stored in the storage means and detected by the displacement detection means. Rank Judging means for judging whether or not the amplitude detection result of the deviation amount is within a predetermined range; and when the judgment means judges that the amplitude detection result is within the predetermined range, If the optimum phase detection result is determined as the optimum phase result and the optimum phase detection processing is terminated, and the determination means determines that the amplitude detection result is not within the predetermined range, the image is determined based on the previous optimum phase detection result. Control means for controlling the rotational phase of the carrier for each predetermined angle to perform the optimal phase detection processing.
[0018]
In order to achieve the above object, an image forming apparatus according to the present invention includes a plurality of image forming units having an optical unit and an image carrier, and a transfer unit that sequentially passes through the plurality of image forming units. A plurality of transfer units for transferring an image onto a recording material placed / conveyed on the conveying unit; a pattern forming unit for forming a pattern for detecting a positional shift on the conveying unit; and a plurality of transfer units formed on the conveying unit. Position deviation detecting means for detecting a pattern for detecting a position deviation, a phase adjusting means for adjusting a rotation phase of the image carrier, and a detection pattern arranged so as to be able to simultaneously detect a reference color and a detection color. Calculating means for calculating the amount of displacement of the detected color with respect to the reference color from the detection result, and fixing the rotational phase of the image carrier with respect to the reference color, and Image carrier rotation The phase is adjusted for each predetermined angle, and the rotation phase with the minimum amplitude is determined as the optimum phase based on the amplitude of the displacement amount and the detected angle information, and the rotation phase of the image carrier is determined as the optimum phase. In an image forming apparatus having an optimum phase detecting means for detecting the determined phase relationship, a storage means for storing an optimum phase of each of the image carriers with respect to a reference color; Judgment for fixing the rotation phase of the image carrier to the optimum phase which is the phase detection result, performing the amplitude detection of the displacement amount, and determining whether the detection result is within a predetermined range. Means for determining an optimum phase detection result based on a previous optimum phase detection result stored in the storage means as an optimum phase detection result when the amplitude detection result of the displacement amount is determined to be within a predetermined range. And end If it is determined that the amplitude detection result of the positional deviation amount is not within a predetermined range, the rotation phase of the image carrier is set to a predetermined angle based on the previous optimum phase detection result stored in the storage unit. And a control means for adjusting each time to perform an optimum phase detection process.
[0019]
In order to achieve the above object, a control method for an image forming apparatus according to the present invention is a control method for controlling an image forming apparatus, wherein the control method is determined by adjusting a rotation phase of an image carrier corresponding to a plurality of colors. The optimal phase result is stored in the memory, and when the rotational phase of the image carrier is adjusted, if the measured value of the displacement amount due to the previous adjustment result phase stored in the memory is within the specified range, the previous phase is directly used. The method further comprises a control step of terminating the rotation phase adjustment with the phase as the optimum phase and, if the rotation phase adjustment is out of the specified range, performing control to execute the rotation phase adjustment at all angles from the previous phase adjustment result. And
[0020]
In order to achieve the above object, a control method for an image forming apparatus according to the present invention is a control method for controlling an image forming apparatus, the method comprising: adjusting a rotation phase of an image carrier corresponding to a plurality of colors. An adjustment step; a displacement detection step of calculating a displacement amount of the detected color with respect to the reference color from a detection result of a detection pattern arranged so as to be able to simultaneously detect the reference color and the detected color; An optimum phase detection step of detecting a rotation phase having the minimum amplitude as an optimum phase of the image carrier based on the amplitude of the displacement amount detected by the step and the detected angle information; and A storage step of storing in the storage means an optimum phase of each image carrier with respect to the reference color determined based on the detection result; and a previous optimum phase detection stored in the storage means. A determination step of fixing the rotational phase of the image carrier to the optimal phase as a result and determining whether or not the amplitude detection result of the displacement amount detected by the displacement detection step is within a predetermined range; If the amplitude detection result is determined to be within a predetermined range by the determination step, the optimum phase detection processing is ended by using the previous optimum phase detection result as the optimum phase result, and the amplitude is determined by the determination step. If it is determined that the detection result is not within the predetermined range, control is performed such that the rotation phase of the image carrier is adjusted at predetermined angles with respect to the previous optimum phase detection result and the optimum phase detection process is performed. And a control step of performing the control.
[0021]
According to another aspect of the present invention, there is provided a method for controlling an image forming apparatus, comprising: a plurality of image forming units having an optical unit and an image carrier; and a conveying unit sequentially passing through the plurality of image forming units. A plurality of transfer means for transferring an image onto a recording material placed / conveyed on or on the conveying means; a pattern forming means for forming a pattern for detecting a displacement on the conveying means; Position detecting means for detecting a pattern for detecting a position formed on the image carrier, a phase adjusting means for adjusting a rotation phase of the image carrier, and a detecting means arranged to detect a reference color and a detected color simultaneously. Calculating means for calculating the positional shift amount of the detected color with respect to the reference color from the detection result of the pattern for use, and fixing the rotational phase of the image carrier with respect to the reference color and applying the detected color with respect to the reference color. Against the image The rotation phase of the image carrier is adjusted by adjusting the rotation phase of the image carrier at each predetermined angle, and determining the rotation phase having the minimum amplitude based on the amplitude of the displacement amount and the detected angle information as the optimum phase. A control method for controlling an image forming apparatus having an optimum phase detecting means for detecting a phase relationship determined as an optimum phase, wherein an optimum phase of each image carrier with respect to a reference color is stored in a storage means. And executing the amplitude detection of the displacement amount by fixing the rotation phase of the image carrier to an optimum phase which is a previous optimum phase detection result stored in the storage unit, and the detection result is determined in advance. A judging step of judging whether or not the amplitude is within a predetermined range; and, if it is judged that the amplitude detection result of the positional deviation amount is within a predetermined range, the judgment of the previous time stored in the storage means is performed. Optimal phase detection When the optimum phase detection processing is terminated as the optimum phase detection result, and it is determined that the amplitude detection result of the positional deviation amount is not within the predetermined range, the previous optimum phase detection result stored in the storage means is stored. A control step of adjusting the rotational phase of the image carrier for each predetermined angle on the basis of the control to perform an optimal phase detection process.
[0022]
In order to achieve the above object, a control program for an image forming apparatus according to the present invention includes a computer-readable control program for controlling an image forming apparatus, wherein a rotational phase of an image carrier corresponding to a plurality of colors is provided. The optimal phase result determined by the adjustment is stored in the memory, and when the rotational phase of the image carrier is adjusted, if the measured value of the displacement amount due to the previous adjustment result phase stored in the memory is within a specified range, In the case where the rotation phase adjustment is finished with the previous phase as the optimum phase as it is and the rotation phase adjustment is out of the specified range, a control step for performing the rotation phase adjustment with the phase of all angles from the previous phase adjustment result is performed. It is characterized by comprising a program code to be executed by a computer.
[0023]
In order to achieve the above object, a control program for an image forming apparatus according to the present invention includes a computer-readable control program for controlling an image forming apparatus, wherein a rotational phase of an image carrier corresponding to a plurality of colors is provided. A phase adjustment step of adjusting the reference color and the detection color, a misregistration detection step of calculating a misregistration amount of the detection color with respect to the reference color from a detection result of the detection pattern arranged so as to be able to be detected simultaneously, An optimal phase detecting step of detecting, as an optimal phase of the image carrier, a rotation phase at which the amplitude is minimized based on the amplitude of the positional deviation amount detected by the positional deviation detecting step and the detected angle information; A storage step of storing, in a storage means, an optimum phase of each image carrier with respect to a reference color determined based on a detection result of the phase detection step; The amplitude detection result of the displacement amount detected in the displacement detection step by fixing the rotation phase of the image carrier to the optimum phase that is the previous optimum phase detection result stored in the means is a predetermined range. A determination step of determining whether the amplitude is within a predetermined range, and, if the amplitude detection result is determined to be within a predetermined range by the determination step, the previous optimal phase detection result is determined as the optimal phase result. When the processing is completed and the result of the determination is that the amplitude detection result is not within the predetermined range, the rotational phase of the image carrier is adjusted for each predetermined angle based on the previous optimum phase detection result. And a control step of controlling the computer to perform an optimum phase detection process.
[0024]
According to another aspect of the present invention, there is provided a control program for an image forming apparatus, comprising: a plurality of image forming units having an optical unit and an image carrier; and a conveying unit sequentially passing through the plurality of image forming units. A plurality of transfer means for transferring an image onto a recording material placed / conveyed on or on the conveying means; a pattern forming means for forming a pattern for detecting a displacement on the conveying means; Position detecting means for detecting a pattern for detecting a position formed on the image carrier, a phase adjusting means for adjusting a rotation phase of the image carrier, and a detecting means arranged to detect a reference color and a detected color simultaneously. Calculating means for calculating the positional shift amount of the detected color with respect to the reference color from the detection result of the pattern for use, and fixing the rotational phase of the image carrier with respect to the reference color and applying the detected color with respect to the reference color. for The rotational phase of the image carrier is adjusted for each predetermined angle by adjusting the rotational phase of the image carrier, and the rotational phase with the smallest amplitude is determined as the optimal phase based on the amplitude of the positional deviation amount and the detected angle information, and A computer-readable control program for controlling an image forming apparatus having an optimal phase detecting unit for detecting a phase relationship determined as a rotational phase determined to be an optimal phase, wherein an optimal phase for a reference color of each image carrier is determined. A storage step of storing in the storage means, and executing the amplitude detection of the displacement amount by fixing the rotational phase of the image carrier to an optimum phase which is a previous optimum phase detection result stored in the storage means. A determining step of determining whether a result of the detection is within a predetermined range; and a step of determining whether or not the amplitude detection result of the displacement amount is within a predetermined range. When it is determined that the optimum phase detection process is finished using the previous optimum phase detection result stored in the storage unit as the optimum phase detection result and that the amplitude detection result of the positional deviation amount is not within a predetermined range, the storage unit A control step of adjusting the rotational phase of the image carrier for each predetermined angle based on the previous optimal phase detection result stored in the computer and performing an optimal phase detection process. Characterized by comprising the following program code.
[0025]
Further, in order to achieve the above object, a storage medium of the present invention stores a control program of the image forming apparatus.
[0026]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0027]
(First embodiment)
First, a first embodiment of the present invention will be described with reference to FIGS.
[0028]
FIG. 1 is a vertical cross-sectional view showing a configuration of a main part of an image forming apparatus according to the present embodiment. FIG. 2 is a main part of a photosensitive drum drive unit / drive transmission unit in the image forming apparatus according to the present embodiment. FIG. 3 is a perspective view showing a configuration, FIG. 3 is a cross-sectional view showing a main configuration of a photoconductor drum driving unit / drive transmission unit in the image forming apparatus according to the present embodiment, and FIG. 4 is an image according to the present embodiment. FIG. 5 is an explanatory diagram showing a configuration of a main part of a drive unit and a control system of a photosensitive drum in the forming apparatus. FIG. 5 is an explanatory diagram showing a state of color misregistration of each color before control in the image forming apparatus according to the present embodiment. FIG. 6 is an explanatory diagram illustrating a state of a signal that detects a phase of a gear that rotationally drives the photosensitive drum in the image forming apparatus according to the present embodiment. FIG. 7 is a diagram illustrating a state of a signal in the image forming apparatus according to the present embodiment. Eliminates color misregistration of each color after body drum phase control FIG. 8 is an explanatory diagram showing a state, and FIG. 8 is an explanatory diagram showing a positional deviation detection pattern and an example of its arrangement in the image forming apparatus according to the present embodiment. FIG. 9 is a photoconductor in the image forming apparatus according to the present embodiment. FIG. 10 is an explanatory diagram showing a positional deviation amount with respect to a reference color when driving unevenness other than the drum is canceled. FIG. 10 is a positional deviation amplitude when the rotation phase of the photosensitive drum in the image forming apparatus according to the present embodiment is changed. FIGS. 11 to 13 are flowcharts showing the flow of the optimal phase detection processing operation of the photosensitive drum in the image forming apparatus according to the present embodiment.
[0029]
In FIG. 1, reference numeral 100 denotes an image forming apparatus (color image forming apparatus) according to the present embodiment, and four yellow, magenta, cyan, and black pixels are arranged in a line from bottom to top in the drawing. Of the electrophotographic photosensitive drums (image carriers) 1y, 1m, 1c, and 1k (hereinafter, simply referred to as (photosensitive drums 1)). A transfer material transport belt (endless belt) 2 which is a transfer material carrier that attracts and transports the transfer material S by suction is provided.
[0030]
Each of the photoconductor drums 1 is fixed to a drum shaft 1a (see FIG. 3) serving as a rotation shaft of the photoconductor drum 1, and more specifically, a coupling 36 (see FIG. 3) which is a first engagement member described later. ) And the gear 18 on the side of the coupling 33 (see FIGS. 2 and 3), which is a second engaging member engaged with and coupled to the coupling 36, is rotated by a driving motor (not shown) serving as a driving source. The driving force is transmitted and rotated in the counterclockwise direction in FIG.
[0031]
The transfer material transport belt 2 is wound around a plurality of rollers 13, 14a, 14b, and 15 and is driven to rotate.
[0032]
The primary chargers 3y, 3m, 3c, 3k, which are charging means for uniformly charging the surface of the photoconductor drum 1, are arranged around the circumference of each photoconductor drum 1 in order from the upstream in the rotation direction. Primary charger 3). "
[0033]
Exposure means 4y, 4m, 4c, and 4k for irradiating a laser beam on the surface of photoreceptor drum 1 uniformly charged by primary charger 3 based on image information to form an electrostatic latent image. Exposure means 4). "
[0034]
Developing means 5y, 5m, 5c, 5k for adhering toner of each color on the surface of photoreceptor drum 1 on which the electrostatic latent image is formed to visualize as a toner image "hereinafter simply referred to as (developing means 5) Is arranged.
[0035]
Cleaning means 6y, 6m, 6c, 6k for removing the toner remaining on the surface of the photoreceptor drum 1 after the transfer (hereinafter, simply referred to as (cleaning means 6)) are arranged.
[0036]
The photosensitive drum 1, the primary charger 3, the developing unit 5, and the cleaning unit 6 are integrally formed as process cartridges 7y, 7m, 7c, and 7k, which are hereinafter simply referred to as (process cartridge 7). , Is detachably attached to the apparatus main body 100a.
[0037]
Although not shown, a detection unit for detecting the replacement of the process cartridge 7 is provided, and the detection unit can detect whether or not the process cartridge 7 is loaded during the initialization operation.
[0038]
At the position facing each photosensitive drum 1, transfer rollers 8y, 8m, 8c, and 8k, which are transfer means with the transfer material conveying belt 2 interposed therebetween, are referred to as "transfer rollers 8". Are located. These transfer rollers 8 transfer the toner image formed on the surface of the photosensitive drum 1 to the transfer material S carried and transported by the transfer material transport belt 2.
[0039]
A driving unit (not shown) for applying a rotational driving force to the four color process cartridges 7 arranged in a substantially vertical direction is provided on the left side of the apparatus main body 100a. Each process cartridge 7 includes the photosensitive drum 1, the developing unit 4, the cleaning unit 6, and the like, and all of these driving forces are supplied by the driving unit.
[0040]
Since the process cartridge 7 can be attached and detached independently of each color, the drive transmission unit is also arranged in a substantially vertical direction independently of each color, and directly transmits the driving force to the photosensitive drum 1 requiring rotation accuracy. However, other driving, for example, driving of the developing unit 4 and the cleaning unit 6 may be transmitted in another system. The driving force supplied to the process cartridge 7 is distributed to each element by a driving system in the process cartridge 7.
[0041]
As shown in FIGS. 2 and 3, a shaft portion 32a that rotates integrally with the gear 18 for driving the process cartridge 7, and a rotation portion that integrally rotates with the shaft portion 32a are provided inside the driving means. And a coupling 33 for transmitting a rotational driving force to the process cartridge 7, and a drum shaft fixed concentrically with the photosensitive drum 1 from the coupling 33 to the shaft 32 a. A positioning hole 34 for fitting to 1a to determine a position is formed. This integral component can be a resin molded product.
[0042]
As shown in FIGS. 2 and 3, the shaft portion 32a is supported by the cylinder bearing portion 35 installed on the apparatus main body 100a side only in the shaft portion 32a in the vicinity of the gear root with the required accuracy so as to freely rotate and linearly move. I have. The peripheral portion of the coupling portion 33 is wide enough that the positioning hole 34 does not conflict with the shaft position determined by fitting the drum shaft 1a, and does not hinder the engagement of the coupling portion 33. There is a clearance that can be supported.
[0043]
The inclination of the gear shaft (shaft portion 32a) occurs due to the positional accuracy between the cylinder bearing portion 35 and the drum shaft 1a. However, by setting the distance from the gear 18 side end of the shaft portion 32a to the positioning hole 34 sufficiently long. Thus, actual harm such as inclination of the gear shaft (shaft portion 32a) is prevented from occurring.
[0044]
The component integrated with the gear 18 is movable in the axial direction, and is pressed by the leaf spring 37 in the direction of the photosensitive drum 1 (to the right in FIG. 3).
[0045]
A drum shaft 1a that rotates integrally with the photosensitive drum 1 is fixed to the photosensitive drum 1 using a fixing pin (not shown), and the drum shaft 1a is accurately positioned on the apparatus main body 100a via a bearing 38. ing.
[0046]
A non-drive side (driven side) coupling 36 is fixed to an end of the drum shaft 1a via a fixing pin 1b. The non-drive side coupling 36 is connected to the drive side (drive side) coupling 33. The meshing and the rotational driving force are transmitted.
[0047]
The driving-side coupling 33 and the non-driving-side coupling 36 are triangular spiral couplings as shown in FIGS. 2 and 3, and when driven in a predetermined direction, they are always engaged with each other. .
[0048]
As shown in FIG. 4, each of the photosensitive drums 1y, 1m, 1c, 1k "hereinafter simply referred to as (photosensitive drum 1)" is used exclusively for motors 41y, 41m, 41c, 41k. 41). "Is provided. A gear 39 fixed to the drive shaft of the motor 41 meshes with the gear 18 fixed to the drum shaft 1a. Then, the photosensitive drum 1 is driven by the motor 41 via the gears 39 and 18.
[0049]
The teeth 31 of the gear 18 shown in FIGS. 2 and 3 are provided with targets 42y, 42m, 42c, and 42k (hereinafter simply referred to as the target 42) for detecting the phase as shown in FIG. The phase signal can be detected once per rotation by the optical or magnetic phase detectors 43y, 43m, 43c, and 43k “hereinafter, referred to as a unit (phase detector 43)”. .
[0050]
In FIG. 4, reference numeral 51 denotes an axis phase detecting unit that detects an axial phase of the photosensitive drum 1, 52 denotes a speed unevenness detecting unit that detects uneven speed of the photosensitive drum 1, and 53 denotes an axial phase detecting unit 51 and an uneven speed detecting unit An arithmetic unit that performs arithmetic processing based on the detection value of 52, and a motor control unit (control means) that controls the motor 41 based on the arithmetic value of the arithmetic unit 53.
[0051]
As shown in FIG. 4, an image detection sensor 44 is provided so as to face the transfer material transport belt 2, and the image on the transfer material transport belt 2 is optically detected by the image detection sensor 44. Can be.
[0052]
In the image forming apparatus according to the present embodiment, since the main component of the angular velocity unevenness is only one rotation period of the photosensitive drum 1, a pattern formed on the photosensitive drum 1 at equal time intervals is transferred to the transfer material conveying belt. 2, the image is read by the image detection sensor 44, and a sine waveform as shown in FIG. 5 is obtained when the accumulated fluctuation component of the pattern interval is obtained.
[0053]
In FIG. 5, the horizontal axis represents the distance from the leading end of the image, and the vertical axis represents the amount of displacement.
[0054]
In order to determine the phase relationship between the four colors, an image is formed for each color while detecting the image forming start timing of each color, and a pattern is detected to obtain a sine waveform as shown in FIG. Processing such as correction and comparison may be performed.
[0055]
In addition, as shown in FIG. 5, when the Bk (black) color is used as a reference, if the Y (yellow) color is shifted toward the front end of the image by the distance y, the color shift relative to the Bk color can be reduced. it can. Similarly, the M (magenta) color may be shifted toward the image front by the distance m, and the C (cyan) color may be shifted toward the image front by the distance c.
[0056]
However, since this phase detection requires a predetermined time, frequent phase detection results in a loss of image forming time.
[0057]
Therefore, usually, the control is performed based on the phase information from the phase detection device 43 that detects the phase of the gear 18 that rotates the photosensitive drum 1.
[0058]
When the phase waveform detected by the phase detection device 43 is in a state as shown in FIG. 6, if the phase of the Y-color gear 18 is controlled so as to be turned earlier by a time y ′ corresponding to the distance y in FIG. The relative color shift between the Bk color and the Y color is reduced. Similarly, the phase control may be performed so that the M-color gear 18 is turned earlier by a time m ′ corresponding to the distance m, and the C-color gear 18 is turned forward by a time c ′ corresponding to the distance c. You only have to control it.
[0059]
This phase control can be performed by adjusting the speed of the motor 41 by the motor control unit 54.
[0060]
When such phase control is performed and the above-described phase relationship is obtained, the state shown in FIG. 7 is obtained, and the relative color shift can be reduced to about １ ／ or less of that of the related art.
[0061]
8 is transferred to the transfer material transport belt 2, and the pattern is read by image detection sensors 44 (see FIG. 4) provided on both sides of the transfer material transport belt 2 to obtain each pattern. Is detected.
[0062]
In FIG. 8, a reference color a (hereinafter, Bk: black) is shown on one side, and a detected color b (hereinafter, Y: yellow, M: magenta, C: cyan) is shown on the other side. In FIG. 8, a1 to a19 and b1 to b19 indicate the detection timings of the respective patterns for detecting the positional deviation, and arrows indicate the transport direction of the transfer material transport belt 2.
[0063]
In the misregistration detection pattern, since the reference color and the detected color are arranged at the same position in the sheet conveyance direction, the pattern is less susceptible to drive unevenness (speed unevenness) caused by the transfer material transfer belt 2.
[0064]
As shown in FIG. 9, the pitch can be canceled by setting the pitch of the misregistration detection pattern to be an integral multiple of the drive unevenness other than the photosensitive drum 1.
[0065]
The rotation phase of the reference color is fixed, the rotation phase of the detected color with respect to this reference color is shifted and detected at each predetermined angle, and the above-described detection processing is repeated to detect the rotation of the reference color. As for the relationship between the rotation phase and the amplitude of a color, a waveform as shown in FIG. 10 can be obtained, and the optimum phase of each color can be easily determined.
[0066]
In FIG. 10, the vertical axis indicates the amplitude of the positional shift amount of the detected color with respect to the reference color, and the horizontal axis indicates the rotation phase of the detected color with respect to the reference color.
[0067]
The amplitude of the displacement amount of the photosensitive drum 1 of the detected color with respect to the reference color of the displacement detection pattern is expressed by the following equations (1) to (3).
[0068]
ΔC1 (θ) = MAX (a1-bc1, a2-bc2,..., A18-bc18, a19-bc19) −MIN (a1-bc1, a2-bc2,..., A18-bc18, a19-bc19) / 2 (1)
ΔY1 (θ) = MAX (a1-by1, a2-by2,..., A18-by18, a19-by19) -MIN (a1-by1, a2-by2,..., A18-by18, a19-by19) / 2 (2)
ΔM1 (θ) = MAX (a1-bm1, a2-bm2,..., A18-bm18, a19-bm19) −MIN (a1-bm1, a2-bm2,..., A18-bm18, a19-bm19) / 2 (3)
Further, there is a method of roughly adjusting the rotation phase of the photosensitive drum 1 for the detection color with respect to the reference color and then finely adjusting the rotation phase, thereby shortening the time.
[0069]
In the present embodiment, first, a positional deviation detection pattern is detected at 120 ° intervals with respect to the reference phase. Using the detection result, an angle between the phase angles where the amplitude of the positional deviation amount is small is detected. Further, using the detection result, a phase angle where the amplitude of the displacement amount is small is measured, and the angle at which the amplitude of the displacement amount becomes the last is determined as the optimum phase.
[0070]
By feeding back the phase detection result to the rotation phase control of the motor 41, color shift can be reduced.
[0071]
The processing operation of the detecting means for detecting the angle between the phase angles having the small amplitude of the positional deviation amount while sequentially changing the phase of the photosensitive drum 1 as described above will be described with reference to FIGS.
[0072]
When detecting the amplitude of the displacement amount in each phase of the photosensitive drum 1, first, the amplitude of the displacement amount with respect to three phases of 0 °, 120 °, and 240 ° is measured (see FIG. 11). Step S1100).
[0073]
As a measurement result for the phases of 0 °, 120 °, and 240 ° in step S1100 in FIG. 11, when it is detected that the amplitude of the displacement amount when the control is performed at the phase of 0 ° is 120 °, With the phase controlled at 180 °, which is the middle of 240 °, the amplitude of the displacement is measured again (step S1101 in FIG. 11).
[0074]
After the completion of the measurement for the 180 ° phase in step S1101 of FIG. 11, the measurement result for the 120 ° phase is the best as the amplitude measurement result of the displacement amount when the control is performed at each phase of 120 °, 180 °, and 240 °. When it is detected that the speed unevenness is small (maximum displacement amplitude), the amplitude of the displacement relative to the 210 ° phase is measured (step S1102 in FIG. 11). Next, the phase with the smallest positional deviation amplitude is determined from 180 °, 210 °, and 240 ° (step S1103 in FIG. 11), and then the processing operation is terminated.
[0075]
After the measurement for the 180 ° phase in step S1101 of FIG. 11 is completed, the measurement result for the 240 ° phase is obtained as the amplitude measurement result of the displacement amount when the control is performed at each phase of 120 °, 180 °, and 240 °. If it is detected that the speed unevenness is the smallest (the maximum displacement amplitude), the amplitude of the displacement relative to the 150 ° phase is measured (step S1104 in FIG. 11). Next, the phase with the smallest positional deviation amplitude is determined from 120 °, 150 °, and 180 ° (step S1105 in FIG. 11), and then the present processing operation ends.
[0076]
Also, as a measurement result for the 0 °, 120 °, and 240 ° phases in step S1100 of FIG. 11, the measurement result for the 120 ° phase detects that the speed unevenness is the smallest (maximum displacement amplitude). Measures the amplitude of the positional shift amount with respect to the 300 ° phase (step S1106 in FIG. 11).
[0077]
After the completion of the measurement for the 300 ° phase in step S1106 in FIG. 11, the measurement result for the 0 ° phase is the most significant as the amplitude measurement result of the positional shift amount when the control is performed at each phase of 0 °, 240 °, and 300 °. When it is detected that the speed unevenness is small (maximum displacement amplitude), the amplitude of the displacement amount with respect to the 270 ° phase is measured (step S1107 in FIG. 11). Next, the phase with the smallest positional deviation amplitude is determined from 240 °, 270 °, and 300 ° (step S1108 in FIG. 11), and then this processing operation ends.
[0078]
After the completion of the measurement for the 300 ° phase in step S1106 of FIG. 11, the measurement result for the 240 ° phase is the most significant as the amplitude measurement result of the positional deviation amount when the control is performed at each phase of 0 °, 240 °, and 300 °. When it is detected that the speed unevenness is small (maximum displacement amplitude), the amplitude of the displacement relative to the 330 ° phase is measured (step S1109 in FIG. 11). Next, the phase having the smallest positional deviation amplitude is determined from 300 °, 330 °, and 0 ° (step S1110 in FIG. 11), and then the present processing operation is terminated.
[0079]
Also, as a result of measuring the phase of 0 °, 120 °, and 240 ° in step S1100 in FIG. 11, the measurement result of the phase of 240 ° detects that the speed unevenness is the smallest (maximum displacement amplitude). Measures the amplitude of the amount of displacement relative to the 60 ° phase (step S1111 in FIG. 12).
[0080]
After the measurement for the 60 ° phase in step S1111 of FIG. 12 is completed, the measurement result for the 120 ° phase is obtained as the amplitude measurement result of the positional deviation amount when the control is performed at each phase of 0 °, 60 °, and 120 °. When it is detected that the speed unevenness is the smallest (maximum displacement amplitude), the amplitude of the displacement relative to the 30 ° phase is measured (step S1112 in FIG. 12). Next, the phase with the smallest positional deviation amount amplitude is determined from 0 °, 30 °, and 60 ° (step S1113 in FIG. 12), and then the present processing operation ends.
[0081]
After the measurement for the 60 ° phase in step S1111 of FIG. 12 is completed, the measurement result for the 0 ° phase is obtained as the amplitude measurement result of the positional deviation amount when the control is performed at each phase of 0 °, 60 °, and 120 °. When it is detected that the speed unevenness is the smallest (maximum displacement amplitude), the amplitude of the displacement relative to the 90 ° phase is measured (step S1114 in FIG. 12). Next, the phase having the smallest positional deviation amplitude is determined from 60 °, 90 °, and 120 ° (step S1115 in FIG. 12), and then the processing operation ends.
[0082]
The phase in which the amplitude of the displacement amount determined in steps S1103, S1105, S1108, and S1110 in FIG. 11 and steps S1113 and S1115 in FIG. 12 is the minimum is determined as the optimal phase of the photosensitive drum 1 in FIG. And is stored in a non-volatile memory (not shown).
[0083]
The motor control unit 54 notified of the result of the amplitude measurement of the displacement amount drives the drive roller 13 (see FIG. 1) of the transfer material conveying belt 2 to maintain the phase of the photosensitive drum 1 according to the measurement result. The driving speed of a motor (not shown) is controlled so that the speed of the transfer material conveying belt 2 matches the peripheral speed of the photosensitive drum 1 and the speed is made uniform.
[0084]
Since the optimum phase of the photosensitive drum 1 stored in the nonvolatile memory is read into the motor control unit 54 when the power is turned on, the optimum phase detection process of the photosensitive drum 1 is performed again when the power is turned off / on. There is no need to do.
[0085]
Here, the processing operation of the control unit that controls the start of the measurement based on the data from the nonvolatile memory when starting the optimal phase detection (measurement) of the photosensitive drum 1 will be described with reference to FIG. .
[0086]
When starting the detection of the amplitude of the positional deviation amount in each phase of the photosensitive drum 1, first, the optimum phase of the photosensitive drum 1 already stored is read from the nonvolatile memory. The phase of the photosensitive drum 1 corresponding to the read optimal phase of the photosensitive drum 1 is set in the motor control unit 54, and the amplitude of the displacement amount is detected (step S1300).
[0087]
Next, it is determined whether or not the amplitude detection result value of the displacement amount detected in step S1300 is within a predetermined range of the amplitude of the displacement amount (step S1301). If it is determined that the optimum phase of the photosensitive drum 1 is already stored in the non-volatile memory, the process ends without updating the optimum phase.
[0088]
On the other hand, if it is determined in step S1301 that the amplitude detection result value of the displacement amount is not within the specified range, the above-described process is performed using the optimum phase of the photosensitive drum 1 already stored in the nonvolatile memory as a reference value. An amplitude detection process for the amount of displacement is performed based on the flowcharts of FIGS. 11 and 12 (step S1302), and then this processing operation ends.
[0089]
As described above, according to the image forming apparatus according to the present embodiment, the phase measurement for controlling the phase of the photosensitive drum 1 is executed by effectively using the phase measurement result of the photosensitive drum 1, whereby While minimizing the phase measurement time of the body drum 1 and further minimizing the consumption of toner and the like, the amount of color misregistration is kept to a minimum, image quality is stabilized, and high-quality image formation is performed. An apparatus can be provided.
[0090]
(Second embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG.
[0091]
The basic configuration of the image forming apparatus according to the present embodiment is the same as that of the above-described first embodiment shown in FIGS.
[0092]
FIG. 14 shows that when the optimum phase detection of the photosensitive drum 1 in the image forming apparatus 100 according to the present embodiment is started, the optimum phase detection of the photosensitive drum 1 is started based on the data from the nonvolatile memory. 5 is a flowchart showing the flow of the operation of the control means for controlling the operation.
[0093]
At the time of shipment of the image forming apparatus 100 according to the present embodiment from the factory, the area of the nonvolatile memory in which the optimum phase of the photosensitive drum 1 is to be written is initially set to data that cannot be obtained by normal detection of the optimum phase of the photosensitive drum 1. It is going to be done.
[0094]
In this state, when starting the detection of the amplitude of the positional deviation amount in each phase of the photosensitive drum 1, first, the optimal phase of the photosensitive drum 1 already stored is read from the nonvolatile memory.
[0095]
It is determined whether or not the read optimal phase of the photosensitive drum 1 is out of the specified range, that is, whether or not the data cannot be obtained by normal optimal phase detection of the photosensitive drum 1 (step S1400). . If it is determined that the data cannot be obtained by the normal detection of the optimum phase of the photosensitive drum 1, the initial phase of the optimum phase detection of the photosensitive drum 1 is set to 0 °, and the data in the first embodiment is determined. An optimal phase detection process for the photosensitive drum 1 is performed based on the same flow as in FIG. 11 and FIG. 12 (step S1404), and then the present processing operation ends.
[0096]
On the other hand, if it is determined in step S1400 that the data can be obtained by normal optimum phase detection of the photosensitive drum 1, the amplitude of the displacement amount is detected (measured) at the phase stored in the nonvolatile memory ( Step S1401).
[0097]
Next, it is determined whether or not the amplitude detection value of the displacement amount detected in step S1401 is within a specified range. Then, when it is determined that the amplitude detection value of the displacement amount is within the specified range, this processing operation is terminated without performing any processing.
[0098]
On the other hand, if it is determined in step S1402 that the detected amplitude value of the displacement amount is not within the specified range, the initial phase of the displacement amount is set to the phase read from the non-volatile memory to the optimum phase of the photosensitive drum 1. Then, based on the phase, the amplitude detection processing of the positional shift amount of all phases is performed based on the same flow as in FIGS. 11 and 12 in the first embodiment (step S1403), and thereafter, this processing operation To end.
[0099]
As described above, according to the image forming apparatus according to the present embodiment, the phase measurement for controlling the phase of the photosensitive drum 1 is executed by effectively using the phase measurement result of the photosensitive drum 1, whereby While minimizing the phase measurement time of the body drum 1 and further minimizing the consumption of toner and the like, the amount of color misregistration is kept to a minimum, image quality is stabilized, and high-quality image formation is performed. An apparatus can be provided.
[0100]
(Other embodiments)
An object of the present invention is to supply a storage medium storing a program code of software for realizing the function of each of the above-described embodiments to a system or an apparatus, and a computer (or CPU, MPU, or the like) of the system or the apparatus stores the storage medium. It is needless to say that the present invention can also be achieved by reading and executing the program code stored in the.
[0101]
In this case, the program code itself read from the storage medium implements the functions of the above-described embodiments, and the storage medium storing the program code constitutes the present invention.
[0102]
Examples of a storage medium for supplying the program code include a floppy (registered trademark) disk, hard disk, magneto-optical disk, CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, and DVD. -RW, DVD + RW, magnetic tape, nonvolatile memory card, ROM, and the like can be used.
[0103]
When the computer executes the readout program code, not only the functions of the above embodiments are realized, but also an OS (Operating System) or the like running on the computer based on the instructions of the program code. Does part of or all of the actual processing, and the processing realizes the functions of the above-described embodiments.
[0104]
Further, after the program code read from the storage medium is written into a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, the function expansion is performed based on the instruction of the program code. It goes without saying that the CPU or the like provided in the board or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.
[0105]
【The invention's effect】
As described above, according to the present invention, the optimum phase detection of the photosensitive drum is executed by effectively using the result of the optimum phase detection of the photosensitive drum. With the time minimized and the consumption of toner and the like minimized, the amount of color misregistration can be kept to a minimum, image quality can be stabilized, and quality can be improved.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view illustrating a main configuration of an image forming apparatus according to a first embodiment of the present invention.
FIG. 2 is a perspective view illustrating a main configuration of a drive unit / drive transmission unit of a photosensitive drum in the image forming apparatus according to the first embodiment of the present invention.
FIG. 3 is a cross-sectional view illustrating a configuration of a main part of a drive unit / drive transmission unit of a photosensitive drum in the image forming apparatus according to the first embodiment of the present invention.
FIG. 4 is an explanatory diagram showing a configuration of a main part of a drive unit of a photosensitive drum and a control system in the image forming apparatus according to the first embodiment of the present invention.
FIG. 5 is an explanatory diagram illustrating a state of color misregistration of each color before control in the image forming apparatus according to the first embodiment of the present invention.
FIG. 6 is an explanatory diagram illustrating a state of a signal that detects a phase of a gear that rotationally drives the photosensitive drum in the image forming apparatus according to the first embodiment of the present invention.
FIG. 7 is an explanatory diagram illustrating a state in which a color shift of each color after phase control of the photosensitive drum in the image forming apparatus according to the first embodiment of the present invention has been eliminated.
FIG. 8 is an explanatory diagram showing a misregistration detection pattern and an example of its arrangement in the image forming apparatus according to the first embodiment of the present invention.
FIG. 9 is an explanatory diagram illustrating a positional shift amount with respect to a reference color when driving unevenness other than a photosensitive drum is canceled in the image forming apparatus according to the first embodiment of the present invention.
FIG. 10 is an explanatory diagram illustrating a change in displacement amplitude when the rotation phase of the photosensitive drum is changed in the image forming apparatus according to the first embodiment of the present invention.
FIG. 11 is a flowchart illustrating a flow of an optimal phase detection processing operation of the photosensitive drum in the image forming apparatus according to the first embodiment of the present invention.
FIG. 12 is a flowchart illustrating a flow of an optimum phase detection processing operation of the photosensitive drum in the image forming apparatus according to the first embodiment of the present invention.
FIG. 13 is a flowchart illustrating a flow of an optimal phase detection processing operation of the photosensitive drum in the color image forming apparatus according to the first embodiment of the present invention.
FIG. 14 is a flowchart illustrating a flow of an optimal phase detection processing operation of a photosensitive drum in the image forming apparatus according to the second embodiment of the present invention.
[Explanation of symbols]
1 Photoconductor drum (image carrier)
1a Drum shaft
1b Fixed pin
1c Photoconductor drum (image carrier)
1k photoconductor drum (image carrier)
1m photoconductor drum (image carrier)
1y Photoconductor drum (image carrier)
2 Transfer material transfer belt (conveyance means, endless belt)
3 Primary charger
3c Primary charger
3k primary charger
3m primary charger
3y primary charger
4 Exposure means
4c Exposure means
4k exposure means
4m exposure means
4y exposure means
5 Developing means
5c developing means
5k developing means
5m developing means
5y developing means
6 Cleaning means
6c Cleaning means
6k cleaning means
6m cleaning means
6y cleaning means
7 Process cartridge
7c process cartridge
7k process cartridge
7m process cartridge
7y process cartridge
8 Transfer roller (transfer means)
8c transfer roller (transfer means)
8k transfer roller (transfer means)
8m transfer roller (transfer means)
8y transfer roller (transfer means)
13 rollers
14a roller
14b roller
15 rollers
18 gears
21 Fixing means
22 Drum shaft
24 discharge tray
32a Shaft
33 Coupling
34 Positioning hole
35 Cylinder bearing
36 Coupling
37 leaf spring
38 Bearing
39 gears
41 motor
41c motor
41k motor
41m motor
41y motor
42 Target
42c target
42k target
42m target
42y target
43 Phase detector
43c phase detector
43k phase detector
43m phase detector
43y phase detector
44 Image Detection Sensor
51 axis phase detector
52 Uneven speed detector
53 arithmetic unit
54 Motor control unit (control means)
S Recording material (transfer material)
100 Image forming apparatus
100a device body

Claims (22)

The optimum phase result determined by adjusting the rotation phase of the image carrier corresponding to a plurality of colors is stored in a memory, and when the rotation phase of the image carrier is adjusted, the position shift due to the previous adjustment result phase stored in the memory is performed. If the measured value is within the specified range, the rotation phase adjustment is terminated with the previous phase as the optimum phase.If the measured value is outside the specified range, the phase of all angles is calculated from the previous phase adjustment result. An image forming apparatus, comprising: a control unit that performs control so as to execute rotation phase adjustment. Phase adjustment means for adjusting the rotation phase of the image carrier corresponding to a plurality of colors,
A displacement detection unit configured to calculate a displacement amount of the detected color with respect to the reference color from a detection result of the detection pattern arranged to be able to simultaneously detect the reference color and the detected color;
Optimum phase detection means for detecting the rotation phase in which the amplitude is minimized as the optimum phase of the image carrier based on the amplitude and the detected angle information of the displacement amount detected by the displacement detection means,
Storage means for storing an optimal phase for the reference color of each image carrier determined based on the detection result of the optimal phase detection means,
An amplitude detection result of a displacement amount detected by the displacement detection means by fixing a rotation phase of the image carrier to an optimum phase which is a previous optimum phase detection result stored in the storage means is predetermined. Determining means for determining whether the distance is within the range;
When the determination means determines that the amplitude detection result is within a predetermined range, the optimum phase detection processing is terminated using the previous optimum phase detection result as the optimum phase result, and the amplitude detection result is determined by the determination means. If it is determined that is not within the predetermined range, the control is performed such that the rotational phase of the image carrier is adjusted for each predetermined angle based on the previous optimal phase detection result to perform the optimal phase detection processing. And an image forming apparatus. 3. The image forming apparatus according to claim 2, wherein the initial value of the previous optimum phase detection result stored in the storage unit at the time of factory shipment is a value that cannot be obtained as a phase measurement result. The control means, if the previous optimal phase detection result stored in the storage means is a numerical value that can not be taken as the optimal phase detection result, the optimal phase detection processing is not executed, 3. The image forming apparatus according to claim 2, wherein the rotation phase of the image carrier is controlled to perform an optimum phase detection process from a predetermined phase position. A plurality of image forming units having an optical unit and an image carrier,
A plurality of transfer units for transferring an image onto a conveying unit that sequentially passes through the plurality of image forming units or onto a recording material placed / conveyed on the conveying unit;
Pattern forming means for forming a pattern for detecting a displacement on the transport means,
Position shift detecting means for detecting a pattern for position shift detection formed on the transport means,
Phase adjustment means for adjusting the rotation phase of the image carrier,
Calculating means for calculating a positional shift amount of the detected color with respect to the reference color from a detection result of the detection pattern arranged so as to be able to simultaneously detect the reference color and the detected color;
The rotational phase of the image carrier is fixed with respect to the reference color, and the rotational phase of the image carrier is adjusted for each predetermined angle with respect to the detected color with respect to the reference color, and the amplitude of the displacement amount is adjusted. An optimal phase detecting means for judging the rotational phase in which the amplitude is minimum as the optimum phase based on the detected angle information and detecting the phase relationship in which the rotational phase of the image carrier is judged as the optimal phase. In the forming device,
Storage means for storing an optimal phase of each of the image carriers with respect to a reference color,
The rotational phase of the image carrier is fixed to the optimal phase, which is the previous optimal phase detection result stored in the storage unit, and the amplitude detection of the positional deviation amount is executed, and the detection result is predetermined. Determining means for determining whether the value is within the range;
When it is determined that the amplitude detection result of the positional deviation amount is within a predetermined range, the optimum phase detection processing is terminated using the previous optimum phase detection result stored in the storage unit as the optimum phase detection result. If it is determined that the amplitude detection result of the displacement amount is not within a predetermined range, the rotation phase of the image carrier is set to a predetermined value based on the previous optimum phase detection result stored in the storage unit. An image forming apparatus comprising: a control unit configured to perform control for performing an optimum phase detection process by adjusting each angle. 6. The image forming apparatus according to claim 5, wherein the initial value of the previous optimum phase detection result stored in the storage unit at the time of shipment from the factory is a value that cannot be obtained as a phase measurement result. If the optimum phase of the previous optimum phase detection result stored in the storage unit is a value that cannot be obtained as the optimum phase detection result, the control unit may not execute the optimum phase detection process. 6. The image forming apparatus according to claim 5, wherein a rotation phase of the image carrier is controlled to perform an optimal phase detection process from a predetermined phase position. In a control method for controlling an image forming apparatus,
The optimum phase result determined by adjusting the rotation phase of the image carrier corresponding to a plurality of colors is stored in a memory, and when the rotation phase of the image carrier is adjusted, the position shift due to the previous adjustment result phase stored in the memory is performed. If the measured value is within the specified range, the rotation phase adjustment is terminated with the previous phase as the optimum phase.If the measured value is outside the specified range, the phase of all angles is calculated from the previous phase adjustment result. A control method for an image forming apparatus, comprising: a control step of performing control to execute rotation phase adjustment. In a control method for controlling an image forming apparatus,
A phase adjustment step of adjusting the rotation phase of the image carrier corresponding to a plurality of colors;
A misregistration detecting step of calculating a misregistration amount of the detected color with respect to the reference color from a detection result of the detection pattern arranged to be able to simultaneously detect the reference color and the detected color;
An optimal phase detection step of detecting a rotation phase in which the amplitude is minimized as the optimal phase of the image carrier based on the amplitude of the displacement amount detected by the displacement detection step and the detected angle information,
A storage step of storing an optimal phase for a reference color of each image carrier determined based on the detection result of the optimal phase detection step in a storage unit,
The rotational phase of the image carrier is fixed to the optimal phase, which is the previous optimal phase detection result stored in the storage unit, and the amplitude detection result of the positional deviation amount detected in the positional deviation detecting step is predetermined. A determining step of determining whether the distance is within the range;
When it is determined by the determining step that the amplitude detection result is within a predetermined range, the optimal phase detection processing is ended by using the previous optimal phase detection result as the optimal phase result, and the amplitude detection result is determined by the determining step. If it is determined that is not within the predetermined range, control is performed such that the rotational phase of the image carrier is adjusted for each predetermined angle based on the previous optimal phase detection result to perform the optimal phase detection processing. And a control method for the image forming apparatus. 10. The method according to claim 9, wherein the initial value of the previous optimum phase detection result stored in the storage unit at the time of factory shipment is a value that cannot be obtained as a phase measurement result. . The control step, if the previous optimal phase detection result stored in the storage means is a numerical value that can not be taken as the optimal phase detection result, the optimal phase detection processing is not executed, the The method according to claim 9, wherein the rotation phase of the image carrier is controlled to perform an optimal phase detection process from a predetermined phase position. A plurality of image forming units having an optical unit and an image carrier, and an image is transferred onto a transporting unit sequentially passing through the plurality of image forming units or onto a recording material placed / conveyed on the transporting unit. A plurality of transfer means, a pattern forming means for forming a pattern for detecting a positional shift on the transport means, a positional shift detecting means for detecting a pattern for detecting a positional shift formed on the transport means, and the image Phase adjustment means for adjusting the rotation phase of the carrier, and calculation for calculating a positional shift amount of the detected color with respect to the reference color from a detection result of a detection pattern arranged so as to be able to simultaneously detect the reference color and the detected color. Means for fixing the rotational phase of the image carrier with respect to the reference color, and adjusting the rotational phase of the image carrier with respect to the detected color with respect to the reference color for each predetermined angle; Quantity amplitude and detection An image forming apparatus that determines a rotation phase in which the amplitude is minimized as an optimum phase based on degree information and detects a phase relationship in which the rotation phase of the image carrier is determined as the optimum phase. In a control method for controlling
A storage step of storing the optimal phase of each image carrier with respect to a reference color in storage means,
The rotational phase of the image carrier is fixed to the optimal phase, which is the previous optimal phase detection result stored in the storage unit, and the amplitude detection of the positional deviation amount is executed, and the detection result is predetermined. A judging step of judging whether it is within the range,
When it is determined that the amplitude detection result of the positional deviation amount is within a predetermined range, the optimum phase detection processing is terminated using the previous optimum phase detection result stored in the storage unit as the optimum phase detection result. If it is determined that the amplitude detection result of the displacement amount is not within a predetermined range, the rotation phase of the image carrier is set to a predetermined value based on the previous optimum phase detection result stored in the storage unit. A control step of performing adjustment for each angle to perform an optimal phase detection process. 13. The method according to claim 12, wherein the initial value of the previous optimum phase detection result stored in the storage unit at the time of shipment from the factory is a value that cannot be obtained as a phase measurement result. . In the control step, when the optimum phase of the previous optimum phase detection result stored in the storage means is a numerical value that cannot be obtained as the optimum phase detection result, the optimum phase detection process has not been executed. 13. The method according to claim 12, wherein the rotation phase of the image carrier is controlled to perform an optimal phase detection process from a predetermined phase position. In a computer-readable control program for controlling the image forming apparatus,
The optimum phase result determined by adjusting the rotation phase of the image carrier corresponding to a plurality of colors is stored in a memory, and when the rotation phase of the image carrier is adjusted, the position shift due to the previous adjustment result phase stored in the memory is performed. If the measured value is within the specified range, the rotation phase adjustment is terminated with the previous phase as the optimum phase.If the measured value is outside the specified range, the phase of all angles is calculated from the previous phase adjustment result. A control program for an image forming apparatus, comprising: a program code for causing a computer to execute a control step of controlling a rotation phase adjustment. In a computer-readable control program for controlling the image forming apparatus,
A phase adjusting step of adjusting the rotation phase of the image carrier corresponding to a plurality of colors, and the detection color for the reference color from a detection result of a detection pattern arranged so that the reference color and the detection color can be simultaneously detected. A displacement detection step of calculating a displacement amount of the image carrier, and a rotation phase in which the amplitude is minimized based on the amplitude and the detected angle information of the displacement amount detected in the position displacement detection step. An optimal phase detecting step of detecting an optimal phase, a storing step of storing an optimal phase for a reference color of each image carrier determined based on a detection result of the optimal phase detecting step in a storage unit, and The rotational phase of the image carrier is fixed to the optimal phase, which is the previous optimal phase detection result stored, and the amplitude of the positional deviation detected in the positional deviation detecting step is detected. A determination step of determining whether the result is within a predetermined range; and, if the amplitude detection result is determined to be within a predetermined range by the determination step, the previous optimal phase detection result is determined. When the optimal phase detection process is completed as the optimal phase result, and the determination step determines that the amplitude detection result is not within the predetermined range, the rotational phase of the image carrier is determined based on the previous optimal phase detection result. And a control step of controlling the computer so as to perform optimal phase detection processing by adjusting the angle for each predetermined angle. 17. The control program according to claim 16, wherein the initial value of the previous optimum phase detection result stored in the storage unit at the time of factory shipment is a value that cannot be obtained as a phase measurement result. . The control step, if the previous optimal phase detection result stored in the storage means is a numerical value that can not be taken as the optimal phase detection result, the optimal phase detection processing is not executed, the 17. The control program for an image forming apparatus according to claim 16, wherein the rotation phase of the image carrier is controlled to perform an optimum phase detection process from a predetermined phase position. A plurality of image forming units having an optical unit and an image carrier, and an image is transferred onto a transporting unit sequentially passing through the plurality of image forming units or onto a recording material placed / conveyed on the transporting unit. A plurality of transfer means, a pattern forming means for forming a pattern for detecting a positional shift on the transport means, a positional shift detecting means for detecting a pattern for detecting a positional shift formed on the transport means, and the image Phase adjustment means for adjusting the rotation phase of the carrier, and calculation for calculating a positional shift amount of the detected color with respect to the reference color from a detection result of a detection pattern arranged so as to be able to simultaneously detect the reference color and the detected color. Means for fixing the rotational phase of the image carrier with respect to the reference color, and adjusting the rotational phase of the image carrier with respect to the detected color with respect to the reference color for each predetermined angle; Quantity amplitude and detection An image forming apparatus that determines a rotation phase in which the amplitude is minimized as an optimum phase based on degree information and detects a phase relationship in which the rotation phase of the image carrier is determined as the optimum phase. A computer-readable control program for controlling the
A storage step of storing the optimal phase of each image carrier with respect to the reference color in a storage unit, and the rotational phase of the image carrier to an optimal phase that is a previous optimal phase detection result stored in the storage unit. A step of executing the amplitude detection of the displacement amount in a fixed manner and determining whether or not the detection result is within a predetermined range; and a step of determining whether the amplitude detection result of the displacement amount is within a predetermined range. If it is determined that the current position is within the range, the optimum phase detection process is terminated by using the previous optimum phase detection result stored in the storage means as the optimum phase detection result, and the amplitude detection result of the displacement amount is determined in advance. When it is determined that the rotation angle is not within the range, the rotational phase of the image carrier is adjusted at predetermined angles with respect to the previous optimal phase detection result stored in the storage unit, and the optimal phase detection process is performed. A control program of the image forming apparatus characterized by comprising a Gosuru control step from the program code to be executed by a computer. 20. The control program according to claim 19, wherein the initial value of the previous optimum phase detection result stored in the storage unit at the time of factory shipment is a value that cannot be obtained as a phase measurement result. . In the control step, when the optimum phase of the previous optimum phase detection result stored in the storage means is a numerical value that cannot be obtained as the optimum phase detection result, the optimum phase detection process has not been executed. 21. The control program for an image forming apparatus according to claim 20, wherein the rotation phase of the image carrier is controlled to perform an optimum phase detection process from a predetermined phase position. A storage medium storing a control program for an image forming apparatus according to claim 15.

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