JP3683666B2 - Optical scanning apparatus and image forming apparatus - Google Patents

Description

従って、待ち時間が必要となる場合についてまとめると、以下の、表２ようなテーブルデータが得られる。
【００９３】
【表２】

【００９４】
以下、動作時の条件に応じてポリゴンモータの回転数を変更する手順の一例を説明する。
図９に示されるように、ポリゴンモータがレディ回転時または停止状態にあるとき、プリンタ機能またはファクシミリ機能またはコピー機能のいづれかが入力されてプリント開始信号が供給されると、ＲＯＭ１０２に記憶されている各機能時の解像度に対応するポリゴンモータの回転数がポリゴンモータ制御回路１５２に設定される (Ｓ１) 。
【００９５】
次に、ポリゴンモータ制御回路１５２によりポリゴンモータが回転される (Ｓ２) 。
以下、ポリゴンモータから対応する機能向けのＰＬＬ信号が出力されるまで、ポリゴンモータ制御回路１５２によりポリゴンモータがモニタされる (Ｓ３) 。
【００９６】
ステップＳ３においてＰＬＬ信号が出力されると (Ｓ３−Ｙｅｓ) 、プリンタＣＰＵ１３０ (またはポリゴンモータ制御回路１５２) により、直前の機能時のポリゴンモータの回転数 (旧回転数) と新たな機能時に必要なポリゴンモータの回転数 (新回転数) が読み込まれる (Ｓ４，Ｓ５) 。
【００９７】
次に、表２に示したテーブルから最適な待ち時間が選択され、ポリゴンモータ制御回路１５２に、待ち時間Ｔｘが設定される (Ｓ６，Ｓ７) 。
以下、ステップＳ７で設定された待ち時間Ｔｘが経過するまでプリンタＣＰＵ１３０により、待ち時間Ｔｘが計数され (Ｓ８) 、待ち時間Ｔｘが経過した時点 (Ｓ８−Ｙｅｓ) で、プリント許可信号が出力される (Ｓ９) 。
【００９８】
【発明の効果】
以上説明したようにこの発明の画像形成装置は、画像形成条件に対応して設定される異なるポリゴンモータの回転数を、画像形成条件に合せて設定する際に、画像形成条件に要求される最適な「待ち時間」を設定できる。これにより、画像形成条件の異なる画像を形成する際に、それぞれの画像形成条件に対して最適なファーストプリント (画像形成時間) 時間を提供する。従って、ユーザに不所望な待ち時間を与えることを防止できる。また、消費電力も低減される。
【図面の簡単な説明】
【図１】この発明の実施の形態が適用される画像形成装置を示す概略図。
【図２】図１に示した画像形成装置の制御部の概略を示すブロック図。
【図３】図１に示した画像形成装置の基本部 (主制御部) の概略を示すブロック図。
【図４】図１に示した画像形成装置の作像部の概略を示すブロック図。
【図５】図１に示した画像形成装置の読取部の概略を示すブロック図。
【図６】図１に示した画像形成装置のファクシミリ部の概略を示すブロック図。
【図７】図１に示した画像形成装置の感光体ドラムの近傍を拡大した概略図。
【図８】図１ないし図７に示した画像形成装置の画像形成条件とレーザ露光タイミングの関係を示すタイミングチャート。
【図９】図８に示したレーザ露光タイミングを提供可能とするポリゴンモータの回転数の制御に利用される制御回路の一例を示すブロック図。
【図１０】図１ないし図７に示した画像形成装置のポリゴンモータの回転数を変更する手順の一例を示すフローチャート。
【図１１】従来の画像形成装置に適用されるレーザ露光タイミングの例を示すタイミングチャート。
【符号の説明】
２ …レーザ露光式複写装置 (画像形成装置) 、
４ …装置本体、
６ …自動原稿送り装置、
８ …フィニッシャ、
１０ …原稿テーブル、
１１ …原稿ガイド、
１２ …露光ランプ、
２３ …結像レンズ、
２４ …ＣＣＤセンサ、
３０ …感光体ドラム (像担持体) 、
３１ …帯電装置、
３２ …レーザ露光装置、
３２ａ…ポリゴンモータ、
３３ …現像装置、
３４ …転写剥離装置、
３５ …クリーニング前除電装置、
３６ …クリーニング装置、
３７ …除電装置、
１００ …システムＣＰＵ、
１０２ …ＲＯＭ、
１０４ …ＲＡＭ、
１３０ …プリンタＣＰＵ、
１４０ …センサ入力部、
１４６ …搬送制御部、
１５０ …レーザ駆動回路、
１５１ …変調回路、
１５２ …ポリゴンモータ制御回路、
１６４ …原稿給紙制御部、
１６６ …アライニングローラ制御部、
１７０ …原稿搬送制御部、
１７２ …原稿サイズ検知回路、
１７４ …センサ入力部、
２０１ …クロック発振回路、
２０２ …分周回路Ｉ、
２０３ …分周回路II、
２０４ …回転数切り替えスイッチ、
２０５ …ＰＬＬ (フェーズループロック) 回路、
２０６ …駆動用トランジスタ、
３０１ …基本部、
３０２ …ページメモリ部、
３０３ …読取部、
３０４ …作像部、
３１１ …主制御部、
３１２ …ファクシミリ、
３１３ …画像処理部。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image forming apparatus that forms an image corresponding to image data by an electrophotographic process and outputs the image on a sheet.
[0002]
[Prior art]
An image forming apparatus using an electrophotographic process charges a photoconductive photoconductor to a predetermined potential, and then irradiates light corresponding to an image to selectively attenuate the photoconductor potential to cause latent image formation. An image is formed, and a toner image obtained by developing with toner as a developer is transferred to a transfer material, thereby forming a copy image of an object to be copied or an image to be printed. Note that image data of an image to be formed is read from a document image by an image reading unit, or is supplied from a communication line or from an external device.
[0003]
The image reading unit includes a CCD reading device that photoelectrically converts reflected light of a document obtained by illuminating the document and converts it into an electrical signal corresponding to image information.
For the purpose of reducing the installation area of the apparatus, the reflected light traveling from the original to the CCD reading apparatus is generally bent multiple times by a plurality of mirrors arranged between the original table and the CCD reading apparatus, and then reflected from the CCD reading apparatus. Guided to the light receiving surface.
[0004]
Around the photoconductor, a charging device that applies a predetermined surface potential to the photoconductor, a developing device that forms a toner image by developing a latent image on the photoconductor surface with toner, and a toner image on the photoconductor is transferred to a recording material A transfer device and a cleaning device that removes transfer residual toner remaining on the surface of the photosensitive member and erases the charge distribution on the surface of the photosensitive member are sequentially arranged along the direction in which the photosensitive member is rotated.
[0005]
In addition, at a predetermined position inside the apparatus, an exposure device that exposes an image on a photoconductor between a developing device and a charging device to form a latent image, and a toner image developed by a transfer device is fixed on a sheet. A fixing device or the like is disposed.
[0006]
In the above-described image forming apparatus, the photoconductor is charged with a predetermined surface potential by the charging device and irradiated with light whose intensity is modulated in accordance with the image data from the exposure device. A latent image corresponding to the image data is formed.
[0007]
The latent image formed on the photoconductor is developed with toner supplied by a developing device and converted into a toner image.
The toner image is a sheet that is electrostatically attracted to the photoconductor by applying a transfer bias voltage having the same polarity as the surface potential provided to the photoconductor from the transfer material, that is, the back surface of the recording paper. It is transcribed.
[0008]
The toner image transferred to the recording material is melted by the heat from the fixing device, and is fixed to the paper by the simultaneously provided pressure.
In this type of image forming apparatus, in recent years, a multi-function machine has been proposed in which a printer function and a facsimile reception (print-out) function are added in addition to a normal copy (copy) function.
[0009]
Such a multi-function machine operates at different resolutions for the copy function, the printer function, and the facsimile function. That is, at the time of facsimile, the resolution is set based on image data transmitted from the other party (transmission source). Similarly, at the time of printer, it is set by a data supply source, that is, a word processor or a host.
[0010]
FIG. 11 is a timing chart showing the relationship between the rotation speed of a polygon mirror that rotates the polygon mirror of the laser exposure type digital copying apparatus described above at a predetermined speed and the time until the rotation speed is reached.
[0011]
As shown in FIG. 11, in the digital copying apparatus, at the start of printing, the rotation speed of the polygon motor is raised (increased) from the ready rotation (or stopped state) to the printable rotation speed. Referring to the PLL (phase loop lock) signal output from the controller, it is determined that the rotational speed has reached a predetermined speed. The rotation speed of the polygon motor is normally set to be higher at the time of copying than at the time of facsimile.
[0012]
However, since the PLL signal from the polygon motor and the actual rotational speed of the motor do not coincide with the moment when the PLL signal is output, normally, a predetermined time T1 (during copying) or after the PLL signal is output. After T2 (during facsimile), a print permission signal is output. Note that the times T1 and T2 from when the PLL signal is output until the predetermined time elapses are merely waiting times, and usually any operation mode (function) is based on the operation time requiring the maximum waiting time Tn. ) Is set identically. In general, the higher the rotation speed of the polygon motor, the longer the time required to reach a stable rotation speed (a print permission signal can be output). That is, in FIG. 11, T1> T2.
[0013]
[Problems to be solved by the invention]
However, in the example shown in FIG. 11, the waiting time T2 (during facsimile) has a problem that T1−T2 = α becomes an unnecessary waiting time.
In this case, there is a problem that the time until the first printout is output, that is, the first print time is increased.
[0014]
SUMMARY OF THE INVENTION An object of the present invention is to provide a first print time optimum for an image forming condition and reduce a waiting time in an image forming apparatus having a plurality of image forming conditions.
[0015]
[Means for Solving the Problems]
The present invention has been made based on the above problems, and has a light source and a mirror surface around the light source. By rotating, the light from the light source is deflected by the mirror surface, and the object is moved at a predetermined speed. A rotating mirror that performs optical scanning, a motor that rotates the rotating mirror at a predetermined speed, and the rotational speed of the motor When changing from any one of the first rotation speed, the second rotation speed, and the rotation speed in the standby state to any one of the first rotation speed and the second rotation speed, the motor After the number of rotations reaches a specific range with respect to the number of rotations after the change, the number of rotations before the change and the number of rotations after the change And a control unit that allows the object to be scanned by the rotating mirror when a time set based on the difference from the time elapses.
[0016]
Further, the present invention has a light source, a mirror surface around it, and deflects light from the light source by the mirror surface by rotating, and an optical scanning means and an optical scanning means for scanning an object at a predetermined speed. Optical scanning means rotating means for rotating the means at a predetermined speed, and the number of rotations of this optical scanning means rotating means When changing from any one of the first rotation speed, the second rotation speed, and the rotation speed in the standby state to any one of the first rotation speed and the second rotation speed, the light After the rotation speed of the scanning means rotation means reaches a specific range with respect to the rotation speed after the change, the rotation speed before the change and the rotation speed after the change And a control means for allowing the optical scanning of the object by the optical scanning means when a time set based on the difference between the optical scanning apparatus and the optical scanning apparatus is provided.
[0017]
Furthermore, this invention Charging means for charging the photosensitive member and laser for emitting laser light modulated according to image information Having a mirror surface around the light source and rotating, the mirror surface by rotating the above laser Deflects light from the light source, An electrostatic latent image is formed on the photosensitive member by optically scanning the photosensitive member charged by the charging unit at a predetermined speed. A rotating mirror, Developing means for developing the electrostatic latent image formed on the photoreceptor, and A motor that rotates the rotating mirror at a predetermined speed and the number of rotations of this motor When changing from any one of the first rotation speed, the second rotation speed, and the rotation speed in the standby state to any one of the first rotation speed and the second rotation speed, the motor After the number of rotations reaches a specific range with respect to the number of rotations after the change, the number of rotations before the change and the number of rotations after the change When the time set based on the difference between The above photoreceptor And an image forming apparatus comprising: a control unit that permits optical scanning of the light source.
[0018]
Still further, the present invention has a charging means for charging the photosensitive member, a laser light source for emitting laser light modulated in accordance with image information, and a mirror surface around it. laser Deflects light from the light source, Optical scanning means for moving an object at a predetermined speed When, An optical scanning means rotating means for rotating the optical scanning means at a predetermined speed; this The rotation speed of the optical scanning means rotation means is any one of the first rotation speed, the second rotation speed, and the standby rotation speed, and is selected from the first rotation speed and the second rotation speed. When changing to one of them, after the rotation speed of the optical scanning means rotation means reaches a specific range with respect to the rotation speed after the change, the rotation speed before the change and the rotation speed after the change When the time set based on the difference between By optical scanning means Control means for allowing optical scanning on the photosensitive member; Developing means for developing the electrostatic latent image formed on the photoreceptor; An image forming apparatus is provided.
[0019]
Furthermore, this invention In an image forming apparatus operable with a copying function and a facsimile function, A charging means for charging the photosensitive member, a laser light source for emitting laser light modulated in accordance with image information, a mirror surface around the surface, and rotating the mirror surface by the mirror surface laser Deflects light from the light source, A rotating mirror that forms an electrostatic latent image on the photosensitive member by optically scanning the photosensitive member charged by the charging unit at a predetermined speed. When, Developing means for developing the electrostatic latent image formed on the photosensitive member, a motor for rotating the rotating mirror at a predetermined speed, and the rotational speed of the motor are set to a first speed when the copying function is executed. The motor control means for rotating the motor at a second speed when the facsimile function is executed, and the motor rotation speed among the first rotation speed, the second rotation speed, and the rotation speed in the standby state. When changing from any one to the first rotation speed and any one of the second rotation speed, after the rotation speed of the motor reaches a specific range with respect to the rotation speed after the change, When the time set based on the difference between the rotation speed before the change and the rotation speed after the change has elapsed, the photoconductor by the rotating mirror And an image forming apparatus comprising: a control unit that permits optical scanning of the light source.
[0020]
Still further, the present invention In an image forming apparatus operable with a copying function and a facsimile function, A charging means for charging the photosensitive member, a laser light source for emitting laser light modulated in accordance with image information, a mirror surface around the surface, and rotating the mirror surface by the mirror surface laser Deflects light from the light source, The above photoreceptor The optical scanning means at a predetermined speed and this Optical scanning means Rotate at a predetermined speed Optical scanning means rotating means And this Optical scanning means rotating means The number of revolutions When changing from any one of the first rotation speed, the second rotation speed, and the rotation speed in the standby state to any one of the first rotation speed and the second rotation speed, the light After the rotation speed of the scanning means rotation means reaches a specific range with respect to the rotation speed after the change, the rotation speed before the change and the rotation speed after the change When the time set based on the difference between The above photoreceptor by optical scanning means The present invention provides an image forming apparatus comprising: a control unit that allows light scanning to the surface; and a developing unit that develops the electrostatic latent image formed on the photosensitive member.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
As shown in FIG. 1, an image forming apparatus, that is, an electrophotographic digital copying apparatus 2 is positioned on an apparatus main body 4 and an upper portion of the apparatus main body 4, and is formed so as to be openable and closable with respect to an original platen described later. It has an automatic document feeder 6 that functions as a document presser that feeds an object, that is, a document one by one toward the document table, and that closely contacts the document with the document table. A finisher 8 for processing a recording sheet holding an image formed by the apparatus main body 4 is connected to the left side of the apparatus main body 4. Note that the automatic document feeder 6 notifies the main controller 311 described later with reference to FIG. 2 that the automatic document feeder 6 is connected to the apparatus main body by the signal line 6a and the finisher 8 by the signal line 8a. .
[0023]
The apparatus main body 4 is disposed at an upper portion of the apparatus main body 10 so as to face the closed automatic document feeder 6 and hold a document to be brought into close contact with the automatic document feeder 6. A document guide 11 indicating a position where the document should be set on the document table 10 is provided. A control panel described in detail in FIG. 7 is disposed in the vicinity of the document table 10 surrounding the document table 10.
[0024]
Below the document table 10, an exposure lamp 12 for illuminating the document set on the document table 10, an auxiliary reflector 13 for condensing light from the exposure lamp 12 on the document D, and reflection from the document D A first mirror 14 or the like that bends light in the left direction in the figure is disposed. The exposure lamp 12, the auxiliary reflector 13 and the first mirror 14 are fixed to the first carriage 15, and are arranged so as to be movable in parallel with the document table 10 as the first carriage 15 moves. The first carriage 15 is reciprocated in the left-right direction in the drawing along the document table 10 by the driving force of a pulse motor (DC motor) (not shown) transmitted by a toothed belt (not shown).
[0025]
On the left side of the document table 10 in the drawing, it is formed to be movable in parallel with the document table 10 by a driving mechanism (not shown) such as a toothed belt (not shown) in the direction in which the reflected light reflected by the first mirror 14 is guided. A second carriage 20 is provided.
[0026]
The second carriage 20 is provided with a second mirror 21 for bending the reflected light from the document guided by the first mirror 14 downward in the figure and a third mirror 22 for bending rightward in the figure at right angles to each other. . The second carriage 20 is moved in parallel along the document table 10 following the first carriage 15 at a speed that is ½ of the speed at which the first carriage 15 is moved.
[0027]
The reflected light reflected by the third mirror 22 is coupled at a predetermined magnification within a plane below the first carriage 15 and including the optical axis of the light reflected by the third mirror 22 of the second carriage 20. An imaging lens 23 to be imaged and a CCD sensor 24 for converting the reflected light given the focusing property by the imaging lens 23 into an electrical signal, that is, image data, are arranged.
[0028]
A photosensitive drum 30 serving as an image carrier is positioned approximately at the center of the apparatus main body 4 so as to be rotatable in a predetermined direction. The photosensitive drum 30 is rotated at a predetermined rotation speed by a motor (not shown).
[0029]
At a predetermined position around the photosensitive drum 30, a charging charger 31 for charging the photosensitive layer on the drum surface to a predetermined surface potential, a laser diode (not shown) as a light source, and laser light from the laser diode are linearly deflected. Polygon mirror 32a,
Predetermined imaging characteristics are given by a polygon mirror motor 32m that rotates the polygon mirror 32a at a predetermined speed, an imaging lens 32b that gives predetermined imaging characteristics to the laser light deflected by the polygon mirror 32a, and an imaging lens 32b. The laser beam from a laser diode including a mirror 32c that reflects the laser beam toward the photosensitive drum 30 and intensity-modulated in accordance with image data supplied from an image processing unit to be described later, that is, image information to be formed. A laser exposure device 32 that forms an electrostatic latent image on the surface of the photosensitive drum 30 by exposing the surface of the photosensitive drum 30, and is formed on the photosensitive layer on the surface of the photosensitive drum 30 by exposure by the laser exposure device 32. A developing device 33 having a developing roller 33a for developing the electrostatic latent image by supplying toner as a developer, which will be described later. A transfer / peeling device 34 for transferring the toner image formed on the photosensitive drum 30 to the recording paper P fed from the paper cassette and separating the paper P having the transferred toner image from the photosensitive drum 30; Of the pre-cleaning static eliminator 35 that improves the cleanability by removing the charge remaining on the photosensitive drum 30 before cleaning, the cleaning device 36 that cleans the toner remaining on the surface of the photosensitive drum 30, and the photosensitive drum 30. A neutralization device 37 for neutralizing the potential remaining on the surface is sequentially arranged.
[0030]
At the bottom of the apparatus main body 4 positioned below the photosensitive drum 30, a multi-stage sheet feeding device 40 is disposed as a sheet feeding means that is stacked in a vertical direction and is detachably mounted from the front side of the apparatus body 4. Has been.
[0031]
The multi-stage sheet feeding device 40 includes an upper cassette 41, a middle cassette 42, and a lower cassette 43 for storing a plurality of types of recording paper P of various sizes, and each of the cassettes 41, 42, and 43 includes, for example, a longitudinal direction. Each of the A4 size copy paper, the B4 size copy paper, and the A3 size copy paper placed so as to be transported along the A3 is formed so as to be capable of storing about 500 sheets.
[0032]
At predetermined positions of the upper cassette 41, the middle cassette 42 and the lower cassette 43, pickup rollers 44a, 44b and 44c for taking out the sheets stored in the respective cassettes 41, 42 and 43 one by one are arranged.
[0033]
Conveying rollers 45a, 45b for separating the paper P one by one and at positions where the leading ends of the paper P taken out from the cassettes 41, 42 and 43 are passed by the respective pickup rollers 44a, 44b and 44c, and 45c and separation rollers 46a, 46b and 46c arranged integrally with the respective conveying rollers are arranged. The separation rollers 46a, 46b, and 46c are arranged so that their axes are in parallel with the transport rollers combined with each other at a predetermined pressure and rotate in a direction opposite to the rotation direction of the transport rollers. As a result, only the uppermost sheet P of the paper P taken out from each cassette is sent out to a conveyance path described later.
[0034]
On the right side of the multi-stage sheet feeding device 40, there is provided a large-capacity cassette 47 formed so that about 3000 sheets of frequently used sheets, for example, A4 size sheets, can be stored.
[0035]
At a predetermined position of the large-capacity cassette 47, a pickup roller 48 for taking out the sheets P stored in the large-capacity cassette 47 one by one is arranged. A separation mechanism 49 including a pair of upper and lower conveying rollers 49 a and a separation roller 49 b is disposed between the pickup roller 48 and the photosensitive drum 30. The separation mechanism 49 rotates the separation roller 49b in a direction opposite to the direction in which the conveyance roller 49a is rotated, thereby conveying only the uppermost sheet taken out from the large-capacity cassette 47 by the pickup roller 48, which will be described later. Send to the road. A paper feed sensor 47 a for detecting the conveyance state of the paper taken out from the large-capacity cassette 47 by the pickup roller 48 is disposed between the pickup roller 48 and the separation mechanism 49.
[0036]
Above the large-capacity cassette 47, the cassettes 41, 42, 43 and the large-capacity cassette 47 are independent of the large-capacity cassette 47, above the side cassette 50 integrally with the side cassette 50 and the side cassette 50. A manual feeder 51 that is formed and capable of feeding one sheet or a non-standard sheet is formed. Note that paper empty switches 50a and 51a for detecting the absence of paper are disposed at the front ends of the side cassette 50 and the manual feeder 51, respectively.
[0037]
Between the manual feeder 51 and the photosensitive drum 30, a pickup roller 52 that takes in the paper P from the manual feeder 51 and a conveyance roller 53 that conveys the paper P taken in by the pickup roller 52 are provided. The transport roller 53 is also used for feeding paper from the side cassette 50.
[0038]
Between the respective cassettes 41, 42 and 43 and the large-capacity cassette 47 and the photosensitive drum 30, conveyance for guiding the paper P from the respective cassettes 41, 42 and 43 and the large-capacity cassette 47 toward the photosensitive drum 30. A path 54 is formed. The conveyance path 54 is formed integrally with a conveyance belt and a fixing device, which will be described later, through a transfer region between the photosensitive drum 30 and the transfer peeling device 34, and is extended to the outside of the apparatus main body 4. Yes.
[0039]
Between the cassettes in the conveyance path 54, the sheet is guided toward the photosensitive drum 30 beyond the conveyance rollers 45a and separation rollers 46a, 45b and 46b, and 45c and 46c arranged corresponding to the respective cassettes. And a plurality of transport roller pairs 55 for transporting papers sent by the respective rollers 45a and 46a, 45b and 46b and 45c and 46 are arranged. 54a, 54b, and 54c match the timing at which the immediately subsequent transport roller pair 55 transports toward the photosensitive drum 30.
[0040]
In the vicinity and upstream of the photosensitive drum 30 in the conveyance path 54, the inclination of the sheet P guided through the conveyance path 54 is corrected, and the leading edge of the toner image on the photosensitive drum 30 and the leading edge of the sheet P are corrected. Aligning rollers 56 for feeding the paper P to the transfer area at the same speed as the movement speed of the outer peripheral surface of the photosensitive drum 30 are disposed.
[0041]
Further, an aligning sensor 56 a that detects the arrival of the paper P at the aligning roller 56 is disposed in front of the aligning roller 56, that is, on the conveying roller 55 side.
[0042]
In the direction in which the sheet that has passed through the transfer region travels, a conveyance belt 57 that guides the sheet on which the image (toner image) has been transferred by the transfer peeling device 34 to the fixing device described later is incorporated.
[0043]
The sheet in which the sheet P is conveyed by the conveyance belt 57 and is difficult to apply heat to the photosensitive drum 30 includes a pair of heat rollers whose roller surfaces are pressed against each other, and the sheet onto which the toner image has been transferred. A fixing device 58 for fixing the toner image on the paper P by pressing the toner image and the paper P while melting the toner image by heating P is provided.
[0044]
A finisher 8 for discharging the paper P on which the toner image is fixed by the fixing device 58 is connected to the side wall of the copying apparatus 2 facing the fixing device 58.
The finisher 8 includes a paper discharge tray 59a that holds the paper P on which the toner image has been fixed by passing through the fixing device 58, and is disposed between the fixing device 58 and the paper discharge tray 59a, and the toner image is fixed by the fixing device 58. The discharged paper P is held under the control of the discharge switching unit 60 that guides the copy paper P to either a paper reversing section (to be described later) or a discharge tray 59a. The finisher 8 includes a pair of reversing rollers 59 b for discharging the sheet discharged from the discharge switching unit 60 onto the discharge tray 59 by inverting the surface on which the toner image is transferred, and one sheet of the discharged sheet. A stapler 59c is provided for stapling each time.
[0045]
The discharge switching unit 60 is disposed between the first and second discharge rollers 61 and 62 that propel the paper P that has passed through the fixing device 58, and the first and second discharge rollers 61 and 62, and is fixed. There is a sorting gate 63 that sorts the sheet that has passed through the apparatus 58 to either a discharge tray 59a (finisher 8) or a sheet reversing section described later. Note that a discharge sensor 62 a that detects the conveyance state of the sheet sent toward the finisher 8 is disposed between the second discharge roller 62 and the finisher 8.
[0046]
The reversing mechanism 64 passes through the transfer region and the fixing device 58 and temporarily accumulates at least one side of the sheet on which the toner image is fixed, the temporary accumulating unit 65, the temporary accumulating unit 65, and the sorting gate 63. A reversing guide path 66 that guides the paper that is arranged between and distributed by the sorting gate 63 and guided to the temporary stacking unit 65, a pickup roller 67 that picks up the sheets stacked in the temporary stacking unit 65 one by one, and a temporary stacking unit The sheet P picked up by the pickup roller 67 from 65 is fed again to the aligning roller 56, and the sheet P guided to the reversing path 68 is fed toward the aligning roller 56. A paper roller 69 is provided. The reversing guide path 66 is provided with a jam sensor 65a for detecting jammed paper, and a paper stop for measuring the timing at which the paper feed roller 69 feeds to the subsequent stage is located in front of the paper feed roller 69. A switch 68a is arranged. The paper stop switch 68a determines that a paper jam (jam) has occurred when no paper is detected after a predetermined time has elapsed after the operation of the pickup roller 67 and the paper feed roller 69 has started.
[0047]
The automatic document feeder 6 has a cover 71, and the rear edge of the cover 71 is attached to the rear side of the upper surface of the copying apparatus 2 by a hinge device (not shown). Is formed so as to be openable and closable with respect to the document table 10 as described above.
[0048]
On the left side of the upper surface of the cover 71, a document feed table 72 that holds a plurality of documents D is disposed. The documents D set on the document feeding table 72 are sequentially taken out one by one on the left side of the document feeding table 72 in the drawing, that is, on one end side of the automatic document feeder 6, and the document table 10 is placed from the left end side in the drawing. A pickup roller 73 for supplying to one end side is arranged.
[0049]
A document detection sensor 72 a that detects whether or not the document D is set on the document feed table 72 is disposed at a predetermined position on the document feed table 72.
In the document take-out direction of the pickup roller 73, that is, on the document table 10 side, the document D picked up by the pickup roller 73 is fed toward the document table 10, and the document D fed by the sheet feed roller 74 is fed. An aligning roller 75 that temporarily holds and removes the inclination of the leading edge of the document is disposed. An aligning sensor 75 a that detects that the document D is conveyed toward the aligning roller 75 is disposed between the aligning roller 75 and the paper feed roller 74.
[0050]
The position facing the document table 10 with the automatic document feeder 6 inside the cover 71 closed is given a size that covers almost the entire document table 10, and includes a pickup roller 73, a feed roller 74, and A conveying belt 76 is arranged for conveying the document D conveyed from the document feeding table 72 via the aligning roller 75 to a predetermined position on the document table 10. The conveyor belt 76 is stretched around a pair of belt rollers 77 arranged on the left and right sides in the figure, and is rotated in both directions on the right side in the figure and the left side in the figure by a belt drive mechanism (not shown).
[0051]
On the right side portion of the automatic document feeder 6, the document D is pressed against the reversing roller 78 and the reversing roller 78 that feeds the document D moved from the left side to the right side in the drawing by the conveying belt 76 toward the outside of the cover 71. The flapper 80 and the flapper 80 for switching whether the document D conveyed by the pinch roller 79, the reverse roller 78 and the pinch roller 79 is returned to the conveying belt 76 or discharged onto a predetermined discharge position, that is, on the cover 71, are set on the discharge side. A paper discharge roller 81 that discharges the document D conveyed by the reversing roller 78 when it is switched, a jam sensor 82 that detects a jam of the document D in the vicinity of the reversing roller 78, and the like are disposed.
[0052]
2 to 6 are block diagrams schematically showing a control unit mechanism of the laser exposure type digital copying apparatus 2 shown in FIG.
As shown in FIG. 2, the electrophotographic digital copying apparatus 2 receives and stores image data from the basic unit 301 and the basic unit 301 constituting the digital copying apparatus 2, and stores the stored image data again as the basic unit 301. The page memory unit 302 is transferred to the page memory unit 302.
[0053]
The basic unit 301 is connected to the main control unit 311 via the system bus 310 and the system bus 310 to which various devices or circuits including the main control unit 311 and the main control unit 311 that control the apparatus body 4 are connected. The CCD sensor 24, which will be described in detail later with reference to FIG. 5 of the apparatus main body 4, a reading unit 303 for transmitting image information to the CCD sensor 24, and the photosensitive drum shown below with reference to FIG. 30 and its peripheral devices, an image forming unit 304, a facsimile 312 and an image processing unit 313. The system bus 310 is connected to a system bus (to be described later) of the page memory unit 302 via the system bus connection unit 314. The image processing unit 313 is connected to the image bus of the page memory unit 302 by the image data interface 315.
[0054]
As shown in FIG. 3, the main control unit 311 includes a system CPU 100 of the digital copying apparatus 2 including the apparatus main body 4, the automatic document feeder 6 and the finisher 8, and warms up the laser exposure copying apparatus 2 to perform image processing. An initial program for enabling formation is stored, a ROM (read only memory) 102 connected to the system CPU 100, and a RAM (random access memory) 104 for temporarily storing numerical data input from the control panel, which will be described later. The NVM (nonvolatile memory) 106 that holds the numerical data set when the apparatus 2 is assembled semipermanently, the image memory 108, the timer memory 110, the timer 112, the internal interface 122, the external interface 124, and the like.
[0055]
7 is connected to the internal interface 122, and the finisher 8 shown in FIG. 1 is connected to the external interface 124. The external interface 124 is connected to an external device (such as a personal computer).
[0056]
A printer CPU 130 and a facsimile 312 for controlling the apparatus main body 4 are connected to the system CPU 100.
Connected to the printer CPU 130 is an image forming unit comprising the photosensitive drum 30 and its peripheral devices shown in FIG. 4, and a CCD sensor 24 and a reading unit 303 for transmitting image information to the sensor 24 shown in FIG.
[0057]
As illustrated in FIG. 4, the image forming unit 304 includes a motor driving unit 132 that drives a motor that rotates the photosensitive drum 30 of the apparatus main body 4 illustrated in FIG. 1 at a desired speed, and a conveyance sensor 54 a of the conveyance unit 54. 54b and 54c, an aligning sensor 56a, a discharge sensor 62a, a jam sensor 65a, and a paper stop switch 68a are detected to notify the printer CPU 130 and the system CPU 100 of the paper conveyance state inside the apparatus main body 4. An input unit 140, a cleaning blade (not shown) of the cleaning device 36, a solenoid (not shown) used for the switching mechanism 60, a mechanism driving unit 141 for turning on / off a driving coil, a lighting time and a passing current value of a fixing lamp of the fixing device 58 To set the fixing temperature within a predetermined range. The lamp controller 142, the charging device 31, the transfer unit and the peeling unit of the transfer peeling device 34, the high voltage output control unit 143 that controls the output voltage of the static elimination device 35 before cleaning, and the static elimination device control unit that controls the static elimination device 37. 144, in order to rotate each of the pickup rollers 44a, 44b and 44c, 48 and 51 at a predetermined timing, a paper feed controller 145 for controlling a paper feed motor disposed corresponding to each roller, a transport roller 45a, 45b, 45c, 55,..., Aligning roller 56 and the like are rotated at a predetermined timing to control a motor disposed in correspondence with each roller, and a laser (not shown) of laser exposure device 32. Laser drive circuit 150 for driving the diode, and light emission control by the laser drive circuit 150 Modulation circuit 151 which together intensity modulated with the image data to be formed a light intensity of the laser beam from the more light-emitting laser diode,
A polygon motor control circuit 152 that rotates a polygon motor 32m integrally formed with the polygon mirror 32a of the laser exposure device 32 at a predetermined speed is used.
[0058]
As illustrated in FIG. 5, the reading unit moves the first carriage 15 including the exposure lamp 12, the auxiliary reflector 13, and the first mirror 14 in the apparatus main body 4 illustrated in FIG. 1 in parallel with the document table 10 at a predetermined speed. A motor driver 160 that drives a pulse motor (not shown) that reciprocates, a lamp controller 162 that controls the terminal voltage of the exposure lamp 12 so that a predetermined amount of light reaches the document on the document table 10, a pickup roller 73, and a paper feed In order to rotate the roller 74 at a predetermined timing, a document feed control unit 164 that controls a document motor arranged corresponding to each roller, and an aligning roller 75 that is rotated by the document feed control unit 164 An aligning roller system that turns on / off a solenoid or drive coil (not shown) to stop and rotate at timing. One of the unit 166, the discharge / reverse control unit 168 that controls the position of the flapper 80, and the belt roller 77 around which the conveyance belt 76 is wound is rotated at a predetermined speed, and the document conveyed toward the document table 10 is conveyed. The document is guided to a predetermined position on the document table 10 and, if necessary, the size (length) of the document is detected based on the output of the document conveyance control unit 170 for discharging or inverting the document and the aligning sensor 75a. The document size detection circuit 172, the jam sensor 82 or the document detection sensor 72a is configured by a sensor input unit 174 that notifies the printer CPU 130 (and the system CPU 100) of the output.
[0059]
As shown in FIG. 5, the output of the CCD sensor 24 is an image processing unit including an A / D conversion circuit 181, a resolution conversion circuit 182, a shading correction circuit 183, an image quality improvement circuit 184, a binarization circuit 185, and the like. By 313, a predetermined characteristic is given and transferred to a predetermined area of the page memory unit 302 via the printer CPU 130 and stored (stored).
[0060]
Next, the page memory unit 302 will be described with reference to FIG. 2 again.
The page memory unit 302 includes a page memory 321 and a communication memory 322 that temporarily store (stores) the supplied image data, and a system control unit 323 that controls access from the basic unit 301 to the page memory 321. An address control unit 324 that generates an address of the memory 321, an image bus 325 used for data transfer between devices in the page memory unit 302, and a control between each device in the page memory unit 302 and the system control unit 324 A data control unit 327 that controls data transfer when transferring data between the page memory 321 and another device via a control bus 326 and an image bus 325 used for signal transfer, and a basic unit 301 Between the basic unit 301 when transferring image data via the image interface 315. Image data interface control unit 328 used for data transfer, when image data is transmitted to a device having a different resolution, the image data is converted to a resolution of another device, or image data received from a device having a different resolution is basically used. A resolution conversion / binary rotation circuit 329 that converts the image forming unit of the unit 301 to a resolution that can be imaged or rotates binary image data by 90 degrees, and compresses the image data for transmission by facsimile or storage on an optical disk A compression / decompression circuit 330 that compresses image data input for a device that transmits and stores data and stores the compressed image data for visual printing, and an image data interface controller 315 and rotate the image data by 90 degrees or -90 degrees when outputting the image data from the image forming unit. Composed of such multilevel rotation memory 331 that is used to output.
[0061]
FIG. 6 is a schematic block diagram illustrating the inside of the apparatus main body 4 shown in FIG. 1, that is, the facsimile 312 of the basic unit 301 shown in FIG.
As shown in FIG. 6, a facsimile 312 is connected to a public line via a modem 190 which is a modem for analog line connection, and CODECs 192 and 192 which are binary image data encoding / decoding apparatuses, EPROM 193 for communication control program, memory for storing image data, pseudo SRAM 195 backed up by battery 194, work RAM 196 used for various processing of image data, additional memory 197, and received by facsimile And an interface 198 for outputting the received data to the image processing unit 313 of the basic unit 301.
[0062]
Next, an operation for copying a document image by the copying apparatus shown in FIGS. 1 to 7 will be described.
The apparatus 2 is warmed up according to a control program stored in the ROM 102 when a main switch (not shown) is turned on, and an image corresponding to the supplied image data in response to a print request or facsimile reception from the external apparatus. Is initialized to be formable. In this case, the display unit of the control panel 200 shown in FIG. A message indicating that the printer is waiting is displayed.
[0063]
When the print key 210 of the control panel 200 is turned on after the document D to be copied is set on the document tray 72 of the automatic document feeder 6, it is checked that the empty sensor 72a of the automatic document feeder 6 is on. After detecting that a document is set on the document tray 72, the pickup roller 73 is driven in response to a drive current supplied from the document feed control unit 164 to a document motor (not shown), and the document tray 72 is loaded. The lowermost document among the set documents is guided to the paper feed roller 74.
[0064]
The document D guided to the paper feed roller 74 is further conveyed toward the aligning roller 75.
Subsequently, when the leading edge of the document D passes through the aligning sensor 75a, a clutch (not shown) is turned on by the aligning roller control unit 166, and the aligning roller 75 is stopped. As a result, the document D taken out from the document tray 72 via the pickup roller 73 is temporarily stopped, whereby the inclination of the document D with respect to the document transport direction is corrected.
[0065]
Next, a drive motor (not shown) is rotated under the control of the document conveyance control unit 170, the belt roller 77 is rotated in the document feeding direction, the conveyance belt 76 is rotated, and a clutch (not shown) is turned off at a predetermined timing. The aligning roller 75 is rotated again, and the document D is fed from the aligning roller 75 to the conveying belt 76.
[0066]
Thereafter, the conveyance belt 76 is rotated by the conveyance motor for a predetermined time, whereby the document D is conveyed onto the document table 10 of the copying apparatus 2. The conveyor belt 76 is stopped after a predetermined time from the trailing edge of the document D passing through the aligning sensor 75a, that is, after a time determined in advance by the interval between the aligning sensor 75a and the document guide 11. Rotation due to inertia is prevented by the brake that does not.
[0067]
On the other hand, when the leading edge of the document D is detected by the aligning sensor 75a, the printer CPU 130 of the basic unit 301 is notified that the document D has been transported to a predetermined position, and then the document size detection circuit 172. Based on the size of the original D detected via the aligning sensor 75a and the copy magnification set by a control panel (not shown), the printer CPU 130 selects a cassette containing paper P having the optimum size. . Subsequently, the reading start position of image data for inputting image data from the CCD line sensor 24 to the page memory 321 is called from the ROM 102 and stored in the RAM 104 in accordance with the input copy magnification. At this time, if the size of the paper P calculated by the printer CPU 130 based on the size of the original and the input copy magnification does not match the size of the image area defined based on the copy magnification, the size of the paper P The reading start position based on the height, that is, the copyable document area is calculated. Further, the writing start position on the photosensitive drum 30 by the laser exposure device 32 is similarly defined and stored in the RAM 104.
[0068]
Next, the exposure lamp 12 of the first carriage 15 is turned on with a predetermined brightness, and the first carriage 15 is moved at a predetermined speed along the original D on the original table 10 by the rotation of a pulse motor (not shown). .
[0069]
Subsequently, the first mirror 14 of the first carriage 15 and the second information are reflected as reflected light generated when the image information of the document D placed on the document table 10 is illuminated by the exposure lamp 12 and the reflection plate 13. The second mirror 21 and the third mirror 22 of the carriage 20 are sequentially reflected, pass through the imaging lens 23, and form an image on the reading surface of the CCD sensor 24.
[0070]
The image information of the original D imaged on the CCD sensor 24, that is, the reflected light from the original D is photoelectrically converted by the CCD sensor 24 at a predetermined resolution, and then the CCD sensor 24 corresponding to the reading start position stored in the RAM 104. Are taken in order from a pixel at a predetermined position (not shown), converted into a digital signal by an A / D conversion circuit 181, and an image including a resolution conversion circuit 182, a shading correction circuit 183, an image quality improvement circuit 184, a binarization circuit 185, and the like. A predetermined characteristic is given by the processing unit 313, and transferred to and stored (stored) in a predetermined area of the page memory 321 of the page memory unit 302 via the printer CPU 130.
[0071]
In parallel with the start of supply of image information to the CCD sensor 24 or at a predetermined timing, a motor drive voltage is supplied from the motor drive unit 132 to a motor (not shown) by the control of the printer CPU 130, and the motor (not shown) is driven at a predetermined speed. The photosensitive drum 30 is rotated at a desired speed. At the same time, the high voltage output control unit 143 applies a predetermined potential from the charging device 31 to the surface of the photosensitive drum 30. For example, the initial surface potential supplied to the photosensitive drum 30 is set to approximately −650 volts.
[0072]
The image data temporarily stored in the page memory 321 is generated by the modulation circuit 151 by using the PLL signal returned from the polygon motor 32m that rotates the polygon mirror 32a of the laser exposure device 32 to the polygon motor printer CPU 130 as an exposure start signal. The light intensity of laser light emitted from a laser diode (not shown) of the exposure device 32 is modulated to form an electrostatic latent image on the surface of the photosensitive drum 30. The rotation speed of the polygon motor 32m that rotates the polygon mirror 32a is:
Based on the resolving power required for the image output from the apparatus main body 4, an appropriate rotation speed is set via the polygon motor control circuit 152 under the control of the printer CPU 130.
[0073]
The electrostatic latent image formed in this way is developed by the high-voltage output control unit 143 with toner supplied from the developing roller 33a of the developing device 33 to which a developing bias voltage of −450 volts, for example, is applied. Further, the toner image is transferred onto the paper P as a toner image by the transfer peeling device 34 to which a predetermined transfer voltage is applied by the high voltage output control unit 143.
[0074]
The toner image transferred to the paper P is peeled off from the surface of the photosensitive drum 30 together with the paper P by the peeling output from the transfer peeling device 34 to which a predetermined peeling voltage is applied by the high voltage output control unit 143, and the conveying belt 57. Then, the toner is conveyed to the fixing device 58 and fixed on the paper P via the fixing device 58.
[0075]
The sheet P on which the toner image is fixed is discharged to a discharge tray 59a of the finisher 9 disposed outside the copying apparatus 2 via first and second discharge rollers 61 and 62.
[0076]
The photoconductive drum 30 having the toner image transferred onto the paper P is continuously rotated, and the photoconductive drum 30 is subjected to a static elimination output from the pre-cleaning static elimination device 35 to which a predetermined pre-cleaning static elimination voltage is applied by the high-voltage output control unit 143. The remaining toner charge remaining on the surface of the toner is discharged, and then the remaining toner is removed by the cleaning device 36. Further, the charge is removed by the discharging device 37, and subsequently used for the next image formation.
[0077]
On the other hand, when all the image information of the first document D currently located on the document table 10 is supplied to the CCD sensor 24, the conveyance belt is controlled by the document conveyance control unit 170 in response to the control of the printer CPU 130. 76 is rotated, the front and back of the document D are interchanged, or the next document D is fed. That is, the conveyance motor is rotated by a drive current to a conveyance motor (not shown) under the control of the document conveyance control unit 170, the belt roller 77 is rotated in a predetermined direction, and the conveyance belt 76 is rotated.
[0078]
As a result, when the document is a single-sided document, the first document currently set on the document table 10 is conveyed toward the reverse roller 78, and a predetermined position of the cover 71 is set by the flapper 80 and the discharge roller 81. The paper is discharged to the original receiving area formed on the paper.
[0079]
Subsequently, the empty sensor 72a checks the presence or absence of the next document D. If the document D remains, the document feeding operation is repeated, and the document table 10 is subsequently repeated in the same manner as the first document. Then, the second document is set and the image information of the second document is read.
[0080]
In this way, a series of image formation is repeated for all the documents D set on the document tray 72 of the automatic document feeder 6.
By the way, the laser exposure type digital copying apparatus 2 has a printer function, a copying machine function, and a facsimile reception (printout) function, and different resolutions are given to the respective functions. The resolution of each function is expressed in units of [dpi (dots per inch)].
Printer function (hours) 600 [dpi]
Copier (copying) function (hours) 400 [dpi]
Facsimile function (hours) 300 [dpi]
Is set to
[0081]
However, as already described with reference to FIG. 11, the higher the rotational speed of the polygon motor, the longer the waiting time from when the PLL motor outputs a PLL (phase loop lock) signal until it reaches true stable rotation. It is known to be long.
[0082]
As shown in FIG. 7, the waiting time is determined by the time during which the sheet is conveyed, that is, by the aligning roller 56, the distance between the transfer region where the photosensitive drum 30 and the transfer peeling device 34 face each other and the aligning roller 56. This is a major factor that increases the first print time because it is several to several tens of times longer than the time required for the leading edge of the stopped paper to reach the transfer area.
[0083]
FIG. 8 is a timing chart showing an example of the operation at the time of facsimile reception (printout) function in the copying apparatus 2 shown in FIGS.
As shown in FIG. 8, when a print start signal is output during the facsimile operation, the rotation speed of the polygon motor 32m is increased from the ready rotation speed to the rotation speed at which 300 [dpi] can be provided by the polygon motor control circuit 152. Increased speed.
[0084]
When the rotation speed of the polygon motor 32m reaches a first rotation speed that is a rotation speed for facsimile, a PLL signal corresponding to the rotation speed for facsimile is output. It should be noted that a time T2 is further required until the rotational speed of the polygon motor 32m reaches the printable rotational speed as already described with reference to FIG. 11 (since FIG. 8 is the same scale as FIG. 11). (The relationship between T1 and T2 is T1> T2).
[0085]
By the way, the time T6 until the paper conveyed simultaneously with the print start signal is detected by the aligning sensor 56a in front of the aligning roller 56 (printable state) and the ready rotation speed after receiving the print start signal, 300 Since there is a relationship of T5> T6 with the time T5 until the speed is increased to a speed capable of providing [dpi], at the time of facsimile, printing can be performed when the time T5 has elapsed. .
[0086]
More specifically, as is apparent from a comparison between FIG. 8 and FIG. 11, in the prior art shown in FIG. 11, when the waiting time during facsimile is T2 and the waiting time during copying is T1, Since T1 = T2 + α, and even when the rotation speed of the polygon motor 32m reaches the printable rotation speed at the time of facsimile, an unnecessary waiting time α elapses because it always waits for the time T1. Therefore, in the conventional example shown in FIG. 11, the waiting time α is added to the first print time T4, which is T4 + α.
[0087]
Next, the time from the output of the PLL signal until the rotation speed of the polygon motor reaches the printable rotation speed will be described taking copying and facsimile (FAX) as an example.
[0088]
FIG. 9 shows an example of the polygon motor control circuit 152. For example, the clock oscillation circuit 201 composed of a crystal oscillation circuit, and the oscillation frequency of the oscillation circuit 201 are determined by the FG (AC generator) of the polygon motor 32m described later. The frequency dividing circuit I202 for reducing the frequency to the same level as the generated frequency, and the frequency reduced to a frequency comparable to the rotational speed of the polygon motor 32m by the frequency dividing circuit I202, the motor 32m is rotated at a predetermined speed. A frequency dividing circuit II203 for providing a motor driving frequency for the motor, a rotation speed changeover switch 204 for taking out one of the frequencies divided into a plurality of stages by the frequency division circuit II203 and providing a reference frequency fs, and a rotation speed changeover switch 204 Frequency output via FG and frequency output by FG described below PLL (Phase loop lock) circuit 205 which amplifies by comparing the phase and frequency, and constituted by a driving transistor 206 for driving the motor 32m on the basis of the output from the PLL circuit 205.
[0089]
More specifically, the polygon motor control circuit 152 divides the oscillation frequency of the clock oscillation circuit 201 by the frequency dividing circuit I202 and then generates a predetermined frequency by the frequency dividing circuit II203, and the PLL circuit 205 via the changeover switch 204. The rotational speed of the polygon motor 32m can be changed by switching the reference frequency fs input to the phase comparison terminal in stages. The changeover switch 204 is switched by a speed control signal A from the printer CPU 130, and generates a frequency for rotating the motor 32m. Thereby, the rotation speed of the motor 32m is switched to a predetermined rotation speed. The AC generator FG integrally assembled with the motor 32m detects the rotational speed of the polygon motor 32m and outputs a frequency signal frg. In this case, since the output frequency f of the AC generator FG, that is, the frequency f of the frequency signal frg is proportional to the rotation speed N of the motor 32m, the frequency signal frg and the reference frequency fs from the frequency dividing circuit II203 are input to the PLL circuit 205. The motor 32m is controlled by controlling the motor drive current supplied to the polygon motor 32m by the PLL circuit 205 so that the rotational frequency of the polygon motor 32m, that is, the frequency signal frg output from the FG coincides with the reference frequency fs. The number of rotations is controlled to a predetermined number.
[0090]
The PLL circuit 205 outputs a PLL signal to the printer CPU 130 as shown in FIG. 8 or FIG. 11 when the difference between the frequency signal frg and the reference frequency fs falls within a predetermined range.
[0091]
Table 1 shows the respective rotation speeds during copying and facsimile (FAX), and the transition of all rotation speeds. Table 1 shows the waiting time when switching from the rotational speed of the vertical item to the rotational speed of the horizontal item.
[0092]
[Table 1]

Therefore, the following table data can be obtained when the case where the waiting time is required is summarized.
[0093]
[Table 2]

[0094]
Hereinafter, an example of a procedure for changing the rotation speed of the polygon motor in accordance with the operating condition will be described.
As shown in FIG. 9, when the polygon motor is in a ready rotation state or in a stopped state, when a printer function, a facsimile function, or a copy function is input and a print start signal is supplied, it is stored in the ROM 102. The rotation speed of the polygon motor corresponding to the resolution at each function is set in the polygon motor control circuit 152 (S1).
[0095]
Next, the polygon motor is rotated by the polygon motor control circuit 152 (S2).
Thereafter, the polygon motor is monitored by the polygon motor control circuit 152 until a PLL signal for the corresponding function is output from the polygon motor (S3).
[0096]
When the PLL signal is output in step S3 (S3-Yes), the printer CPU 130 (or polygon motor control circuit 152) causes the rotation speed (old rotation speed) of the polygon motor at the previous function and the new function to be necessary. The rotation speed (new rotation speed) of the polygon motor is read (S4, S5).
[0097]
Next, the optimum waiting time is selected from the table shown in Table 2, and the waiting time Tx is set in the polygon motor control circuit 152 (S6, S7).
Hereinafter, the waiting time Tx is counted by the printer CPU 130 until the waiting time Tx set in step S7 has passed (S8), and when the waiting time Tx has passed (S8-Yes), a print permission signal is output. (S9).
[0098]
【The invention's effect】
As described above, the image forming apparatus according to the present invention is the optimum required for image forming conditions when setting the rotation speeds of different polygon motors corresponding to the image forming conditions to match the image forming conditions. You can set “waiting time”. Thus, when images having different image forming conditions are formed, an optimum first print (image forming time) time is provided for each image forming condition. Therefore, it is possible to prevent the user from giving an undesired waiting time. Also, power consumption is reduced.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing an image forming apparatus to which an embodiment of the present invention is applied.
FIG. 2 is a block diagram showing an outline of a control unit of the image forming apparatus shown in FIG.
3 is a block diagram showing an outline of a basic part (main control part) of the image forming apparatus shown in FIG. 1;
4 is a block diagram showing an outline of an image forming unit of the image forming apparatus shown in FIG.
FIG. 5 is a block diagram showing an outline of a reading unit of the image forming apparatus shown in FIG.
6 is a block diagram showing an outline of a facsimile unit of the image forming apparatus shown in FIG.
7 is an enlarged schematic view of the vicinity of a photosensitive drum of the image forming apparatus shown in FIG.
FIG. 8 is a timing chart showing the relationship between image forming conditions and laser exposure timing of the image forming apparatus shown in FIGS. 1 to 7;
9 is a block diagram showing an example of a control circuit used for controlling the number of revolutions of a polygon motor that can provide the laser exposure timing shown in FIG. 8. FIG.
10 is a flowchart showing an example of a procedure for changing the rotation speed of a polygon motor of the image forming apparatus shown in FIGS. 1 to 7; FIG.
FIG. 11 is a timing chart showing an example of laser exposure timing applied to a conventional image forming apparatus.
[Explanation of symbols]
2 ... Laser exposure type copying machine (image forming machine)
4 ... the device body,
6 ... Automatic document feeder,
8… Finisher,
10 ... manuscript table,
11 ... Document guide,
12 ... exposure lamp,
23: Imaging lens,
24 ... CCD sensor,
30 ... photosensitive drum (image carrier),
31 ... charging device,
32 ... laser exposure apparatus,
32a ... polygon motor,
33. Developing device,
34 ... transfer peeling device,
35 ... neutralizing device before cleaning,
36 ... cleaning device,
37 ... neutralizing device,
100: System CPU,
102… ROM,
104 ... RAM,
130 ... printer CPU,
140 ... sensor input section,
146... Transport control unit,
150 ... laser drive circuit,
151... Modulation circuit,
152 ... polygon motor control circuit,
164 ... Document feed control unit,
166 ... aligning roller controller,
170 ... Document transport control unit,
172 ... Document size detection circuit,
174 ... sensor input section,
201 ... clock oscillation circuit,
202 ... Frequency dividing circuit I,
203 ... Frequency divider II,
204 ... rotation speed changeover switch,
205 ... PLL (phase loop lock) circuit,
206 ... Driving transistor,
301 ... basic part,
302 ... page memory section,
303 ... reading unit,
304 ... image forming unit,
311 ... main control unit,
312: facsimile,
313: Image processing unit.

Claims (6)

A light source;
A rotating mirror that has a mirror surface around it, deflects light from the light source by the mirror surface by rotating, and optically scans the object at a predetermined speed;
A motor that rotates the rotating mirror at a predetermined speed;
The rotation speed of the motor is changed from any one of the first rotation speed, the second rotation speed, and the standby rotation speed to any one of the first rotation speed and the second rotation speed. When changing, the elapsed time set based on the difference between the rotation speed before the change and the rotation speed after the change after the rotation speed of the motor reaches a specific range with respect to the rotation speed after the change Then, a control means for allowing light scanning to the object by the rotating mirror,
An optical scanning device comprising: A light source;
A mirror surface is provided around, and the light from the light source is deflected by the mirror surface by rotating, and the object is scanned at a predetermined speed with an optical scanning unit.
An optical scanning means rotating means for rotating the optical scanning means at a predetermined speed;
The number of rotations of the optical scanning unit rotating unit is changed from any one of the first number of rotations, the second number of rotations, and the number of rotations in a standby state to the first number of rotations and the second number of rotations. When changing to either one, after the rotation speed of the optical scanning means rotation means reaches a specific range with respect to the rotation speed after the change , the difference between the rotation speed before the change and the rotation speed after the change Control means for allowing the optical scanning of the object by the optical scanning means after a time set based on
An optical scanning device comprising: Charging means for charging the photoreceptor;
A laser light source that emits a laser beam modulated according to image information ;
The photosensitive member has a mirror surface around it, rotates the deflected light from the laser light source by the mirror surface , and optically scans the photosensitive member charged by the charging means at a predetermined speed. A rotating mirror that forms an electrostatic latent image thereon ,
Developing means for developing the electrostatic latent image formed on the photoreceptor;
A motor for rotating the rotating mirror at a predetermined speed,
The rotation speed of the motor is changed from any one of the first rotation speed, the second rotation speed, and the standby rotation speed to any one of the first rotation speed and the second rotation speed. When changing, the elapsed time set based on the difference between the rotation speed before the change and the rotation speed after the change after the rotation speed of the motor reaches a specific range with respect to the rotation speed after the change Then, a control means for allowing light scanning on the photosensitive member by the rotating mirror,
An image forming apparatus comprising: Charging means for charging the photoreceptor;
A laser light source that emits a laser beam modulated according to image information;
A mirror surface is provided around, and the light from the laser light source is deflected by the mirror surface by rotating, and an object is scanned at a predetermined speed with an optical scanning unit .
An optical scanning means rotating means for rotating the optical scanning means at a predetermined speed;
The number of rotations of the optical scanning unit rotating unit is changed from any one of the first number of rotations, the second number of rotations, and the number of rotations in a standby state to the first number of rotations and the second number of rotations. When changing to either one, after the rotation speed of the optical scanning means rotation means reaches a specific range with respect to the rotation speed after the change , the difference between the rotation speed before the change and the rotation speed after the change Control means for allowing light scanning on the photosensitive member by the light scanning means when a time set based on
Developing means for developing the electrostatic latent image formed on the photoreceptor;
An image forming apparatus comprising: In an image forming apparatus operable with a copying function and a facsimile function,
Charging means for charging the photoreceptor;
A laser light source that emits a laser beam modulated according to image information;
The photosensitive member has a mirror surface around it, rotates the deflected light from the laser light source by the mirror surface , and optically scans the photosensitive member charged by the charging means at a predetermined speed. A rotating mirror that forms an electrostatic latent image thereon ,
Developing means for developing the electrostatic latent image formed on the photoreceptor;
A motor for rotating the rotating mirror at a predetermined speed;
Motor control means for rotating the rotational speed of the motor at a first speed when executing the copying function, and rotating at a second speed when executing the facsimile function;
The number of rotations of the motor is any one of the first number of rotations, the second number of rotations, and the number of rotations in a standby state, one of the first number of rotations, and the second number of rotations. When changing to one, after the rotation speed of the motor reaches a specific range with respect to the rotation speed after the change, it is set based on the difference between the rotation speed before the change and the rotation speed after the change. When the time has elapsed, control means for allowing the optical scanning of the photosensitive member by the rotating mirror ;
An image forming apparatus comprising: In an image forming apparatus operable with a copying function and a facsimile function,
Charging means for charging the photoreceptor;
A laser light source that emits a laser beam modulated according to image information;
A mirror surface is provided around the surface, and by rotating, the light from the laser light source is deflected by the mirror surface, and the photoconductor is scanned at a predetermined speed with an optical scanning unit.
An optical scanning means rotating means for rotating the optical scanning means at a predetermined speed;
The number of rotations of the optical scanning unit rotating unit is changed from any one of the first number of rotations, the second number of rotations, and the number of rotations in a standby state to the first number of rotations and the second number of rotations. When changing to either one, after the rotation speed of the optical scanning means rotation means reaches a specific range with respect to the rotation speed after the change , the difference between the rotation speed before the change and the rotation speed after the change Control means for allowing light scanning on the photosensitive member by the light scanning means when a time set based on
Developing means for developing the electrostatic latent image formed on the photoreceptor;
An image forming apparatus comprising:

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