JP2010091975A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To further improve the certainty of operation for arranging a sensor for pattern detection for position detection at a reasonable position for each paper size compared with the case that this constitution is not prepared. <P>SOLUTION: Attention is focused on the fact that guide plates 302 and 304 disposed on a paper feed tray 124 are moved according to the width dimension of recording paper P mounted to the paper feed tray 124, and this movement is transmitted to moving plates 328 and 330 attached with a density sensor 155 using a mechanical operation amount transmission mechanism as a wire transmission mechanism 326. In routing the inside of the apparatus, the wire transmission mechanism 326 has flexibility together with an inner wire 320 and an outer wire 322, so that the apparatus is arranged along a space in the apparatus regardless of a relative position to the paper feed tray 124 and the density sensor 155. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image forming apparatus.

  In recent years, color image forming apparatuses have become widespread in image forming apparatuses such as printers and copiers. In this type of image forming apparatus, for example, each image forming unit provided for development using toner for each color of black (K), yellow (Y), magenta (M), and cyan (C), Some are arranged along the moving direction of a transfer object such as a recording sheet by a sheet conveying belt. An intermediate transfer body system is available as a tandem type image forming apparatus having a structure comparable to the paper transport system.

  In order to correct the positional deviation of the images formed by the respective image forming units, for example, a position detection pattern is formed on a paper conveyance belt or paper, and a sensor is arranged on the movement locus of the position detection pattern.

  The sensors are fixedly arranged in accordance with the maximum size of the applied paper at both ends in the direction orthogonal to the paper transport direction.

Patent Document 1 discloses that a moving mechanism including a motor or the like that moves the sensor position by instructing the size according to the paper size to be applied is disclosed.
JP 2001-150722 A

  The image forming apparatus according to the present invention can improve the reliability of the operation for disposing the position detection sensor for detecting the position detection pattern at an appropriate position for each paper size as compared with the case without this configuration. Is the purpose.

  According to the first aspect of the present invention, an image is formed on a deflector that deflects the light output from the optical scanning unit and an image holding member that moves in the sub-scanning direction intersecting the main scanning direction by the deflected scanning light. A plurality of image forming units to be formed, and an image forming unit that forms a single image on a recording sheet by superimposing images formed by the plurality of image forming units; and the recording sheet is temporarily stored in the apparatus. And a recording paper feeding means for taking out the recording paper from the tray based on an image forming instruction and sending it to the image forming position in the image forming means, and provided in the tray, according to the width of the recording paper. A motion transmitting member that is an amount of motion that is linked to the movement of the guide plate that moves, and a detection locus along the sub-scanning direction, and is formed on the detection locus by the image forming means, A position detection sensor that can detect a position detection pattern that can recognize position information in the inspection direction and that can move in the width direction of the recording paper according to the operation of the operation transmitting member, and a position detected by the position detection sensor Misregistration adjustment execution means for executing misregistration adjustment based on the detection pattern.

  According to a second aspect of the present invention, in the first aspect of the present invention, the motion transmission member is a cylindrical outer cable having flexibility, and is accommodated in the outer cable along the curvature of the outer cable. A flexible inner cable movable in the axial direction, one end of the inner cable receiving the moving force of the guide plate, and the other end transmitting the moving force to the sensor.

  According to the first aspect of the present invention, it is possible to improve the reliability of the operation for arranging the position detection pattern detection sensor at an appropriate position for each paper size as compared with the case without this configuration. it can.

  According to the second aspect of the present invention, the movement amount of the guide plate can be linked as the movement amount of the sensor.

(Overall configuration of image forming apparatus)
FIG. 1 is a diagram illustrating a configuration of an image forming apparatus 110 according to the present embodiment.

  The image forming apparatus 110 includes four process cartridges 120 that perform full color image formation with four color toners (yellow (Y), magenta (M), cyan (C), and black (K)) in the vertical direction corresponding to each color. Are arranged.

  The toners Y, M, C, and K are not particularly limited by the manufacturing method, and various toners can be used.

  Here, the process cartridge 120 is provided for the photosensitive drum 116, the charging roll 118 disposed around the photosensitive drum 116, the erase lamp 122, and the electrostatic latent image formed on the photosensitive drum 116. The developing devices 111A, 111B, 111C, 111D and the like for developing the toner of each color.

  On the other hand, at the lower part of the image forming apparatus 110, a paper feed tray 124 in which the recording paper P is stored is provided. In the vicinity of the paper feed tray 124, a pickup roll 126 that feeds the recording paper P at a predetermined timing is provided.

  The pickup roll 126 feeds the recording paper P from the paper feed tray 124 and transports the recording paper P to the transport device 144 that transports the recording paper P to the process cartridge 120 via the transport roll 128, the paper transport path 132, and the registration roll 130.

  The process cartridge 120 is arranged in the order of the aforementioned Y, M, C, and K colors from the upstream side (the lower side of the paper surface) of the paper transport path 132. An optical scanning device 20 that irradiates the process cartridge 120 with scanning light is disposed on the left side of the process cartridge 120 in FIG.

  The optical scanning device 20 is covered by a housing 20A, and condenses light beams emitted from monolithic semiconductor lasers (surface emitting lasers) of Y to K4 colors with a collimator lens and a cylindrical lens. It is deflected (scanned) in the main scanning direction, enters the fθ lens, and is divided in the sub-scanning direction by two colors.

  The light beam emitted from the fθ lens is finally divided one by one in the sub-scanning direction by the plurality of reflecting mirrors 25 and forms an image on each photosensitive drum 116.

  The conveyance device 144 includes a pair of tension rolls 146 and 148 provided along the side wall 110 </ b> A of the image forming apparatus 110, and a conveyance belt 150 wound around the tension rolls 146 and 148.

  A suction roll 154 is disposed in the vicinity of the tension roll 146, and the recording paper P is electrostatically attracted to the transport belt 150 by applying a bias voltage to the suction roll 154. The tension roll 148 is rotated by a motor (not shown) and moves the conveyor belt 150 along the side wall 110A. A density sensor 155 (image position detector) that detects the density of the reference patch is provided at a position facing the stretching roll 148 with the conveyance belt 150 interposed therebetween.

  Transfer rolls 152 are disposed at positions on the inner peripheral side of the conveyance belt 150 and facing the photosensitive drums 116 of the respective colors. Each transfer roll 152 sequentially transfers the toner images Y, M, C, and K formed on the photosensitive drum 116 onto the recording paper P conveyed by the conveyance belt 150.

  The fixing device 156 fixes the toner image transferred to the recording paper P. The discharge roll 158 discharges the recording paper P on which the toner image is fixed to the discharge tray 160.

  The control unit 166 controls the entire apparatus. For example, the control unit 166 controls the exposure device 134 and the developing device 111 based on image data input from the outside and the output of the density sensor 155.

  In addition, each transfer roll 152 sequentially transfers the toner images Y, M, C, and K of the position detection pattern (reference patch) 153 formed on the photosensitive drum 116 to the conveyance belt 150. Here, the position detection pattern 153 (see, for example, FIG. 2) is used to measure the toner density and the reference patch position in the developing device 111. Specifically, image forming conditions such as toner supply to the developing device 111 and exposure amount are controlled according to the density of the position detection pattern 153 detected by the density sensor 155. A line S in FIG. 2 is a detection locus of the density sensor 155. The density sensor 155 also serves as position detection. The position of the position detection pattern 153 is measured by measuring the timing at which each position detection pattern 153 passes through the density sensor 155, and a deviation amount is detected. An image formation start timing correction amount and a main scanning direction magnification shift correction amount are determined according to the measured shift amount.

  In the so-called tandem type image forming apparatus 110 configured as described above, each image forming unit itself is caused by various factors such as vibration during transportation and installation, opening and closing of a paper feed tray, temperature change, and secular change. Position, and the photosensitive drum 116, the optical scanning device 20 and the like constituting each image forming unit may cause positional fluctuations and image misregistration (also referred to as color registration misalignment) may occur. Table 1 shows an example.

  As shown in Table 1, due to various causes, the position in the main scanning direction and the sub scanning direction, the magnification in the main scanning direction, the partial magnification in the main scanning direction, the magnification in the sub scanning direction, the partial magnification in the sub scanning direction, the lead Skew, side skew, lead linearity, side linearity, periodic deviation in the sub-scanning direction, periodic deviation in the main scanning direction, and the like. Misalignment (uniform misalignment) or AC misalignment (periodic misalignment) may occur and appear as color registration misalignment.

  Therefore, a position detection pattern 153 is formed on the conveyor belt 150 at a specific time, and the position detection pattern 153 is detected by the density sensor 155 to detect position information of the position detection pattern, thereby obtaining a positional deviation amount of the image. The calculation and correction (feedback correction) of the color registration misalignment amount is generally performed.

  As shown in FIG. 3, the control unit 166 includes a microcomputer 10. A non-volatile memory (NVM) 12 is connected to the microcomputer 10 as storage means for storing image information and parameters of a registration error detection pattern used as appropriate in the registration error correction operation.

  The microcomputer 10 of the control unit 166 is connected to an image data control circuit 14 having a drawing memory for developing image data. From the image data control circuit 14, the optical scanning unit 167 is connected. Image data of each color is sent to the laser drive control unit 16. The optical scanning unit 167 synchronizes by exchanging signals with the control unit 166 and controls the laser drive control unit 16.

  The control unit 166 is connected to a user interface (UI) 170. The UI 170 is a so-called touch panel type. Areas such as input keys and selection boxes are displayed on the screen, and an input instruction is given by touching a predetermined area with a finger or the like.

  As shown in FIG. 3, the control unit 166 also functions as a positional deviation amount calculation means for calculating the positional deviation amount of each image formation based on the detection result of the position detection pattern 153 by the density sensor 155. ing.

  In the color registration misregistration amount calculation and correction operation, first, in order to measure the current color misregistration amount, a position detection pattern 153 is formed on the conveyance belt 150 via the photosensitive drum 116, and this position detection pattern is measured. 153 is detected by the density sensor 155, the color misregistration amount is calculated based on the detection data of the density sensor 155, the color misregistration correction amount for correcting the color misregistration is determined from the calculation result, and finally the color A shift correction operation is performed.

  In the color misregistration correction operation, as shown in FIG. 4, the color misregistration in the sub-scanning direction (SS direction) is corrected by adjusting the vertical synchronization signal output for each page. Further, the color shift in the main scanning direction is corrected by adjusting the horizontal synchronizing signal output for each main scanning line.

  By the way, the density sensor 155 is generally arranged in the vicinity of both end portions in the width direction of the conveying belt 150, and this position is a recording capable of forming an image in the image forming apparatus 110 of the present embodiment. It is also in the vicinity of both ends in the width direction of the maximum size of the paper P.

  On the other hand, the size of the recording paper P varies widely, for example, from postcard size to A3 size, and the recording paper P is selectively loaded in the paper feed tray 124 of the image forming apparatus 110.

  Even if the paper size varies in this way, if the position of the density sensor 155 is not changed, proper positional deviation correction (particularly, color deviation correction in the sub-scanning direction) may not be performed.

  Therefore, in the present embodiment, the position of the density sensor 155 is set to an appropriate position (applied recording sheet) without using an electrical control system in accordance with the size of the recording sheet P loaded in the sheet feeding tray 124. It can be arranged in the vicinity of both ends of P).

  As shown in FIG. 5, the paper feed tray 124 includes a box body 300 having an upper opening, and a pair of guide plates 302 and 304 that are erected inward of the box body 300 and are parallel to each other. Yes.

  The guide plates 302 and 304 are configured to face each other in the conveyance width direction of the recording paper P loaded in the paper feed tray 124.

  The bottom 300A of the box 300 is provided with rectangular long holes 300B and 300C whose longitudinal direction is the conveyance width direction.

  As shown in FIGS. 6A and 6B, plates 306 and 308 for supporting the guide plates 302 and 304 are inserted into the long holes 300B and 300C, respectively, and one end thereof is a guide. It is fixed to the plates 302 and 304.

  The other ends of the plates 306 and 308 are fixed to gear plates 310 and 312 disposed on the bottom 300A of the box 300, respectively.

  The gear plates 310 and 312 are parallel to each other, and the longitudinal direction thereof is arranged along the conveyance width direction. The gear plates 310 and 312 are formed with tooth portions 310A and 312A, and the tooth portions 310A and 312A are opposed to each other with a predetermined interval.

  A gear 314 is interposed between the gear plates 310 and 312, and the rotating shaft 314 </ b> A (see FIG. 6B) rotates to the bottom portion 300 </ b> A of the box body 300 while meshing with both the tooth portions 310 </ b> A and 312 </ b> A. Supported as possible.

  In the above structure, when at least one of the guide plates 302 (or 304) is moved in the conveyance width direction, this movement is performed via the teeth 310A and the gear 314 of the gear plate 310 connected to the one guide plate 302 and the other. Is transmitted to the tooth portion 312A of the gear plate 312 connected to the guide plate 304.

  As a result, the guide plates 302 and 304 move in the conveyance width direction without moving their center positions (the movement amount is the same).

  Here, when the recording paper P is loaded inside the box 300, that is, between the guide plates 302 and 304, the recording paper P is placed with the guide plates 302 and 304 wider than the width of the recording paper P. After loading, when the guide plates 302 and 304 are moved so as to press against the widthwise ends of the recording paper P, the recording paper P is held in the center in the transport direction and guided in the transport width direction. .

  As shown in FIG. 6B, a take-up reel 316 is attached to the rotation shaft 314 </ b> A of the gear 314. The take-up reel 316 rotates with the gear 314. The take-up reel 316 is accommodated in the casing 318.

  In the take-up reel 316, a take-up portion 316C having a semicircular bottom surface is formed between a pair of flange plates 316A and 316B, and one end of the inner cable 320 is fixed. For this reason, the inner cable 320 is configured to be wound or pulled out by the winding portion 316C depending on the rotation direction of the winding reel 316. The inner cable 320 is formed in a cylindrical shape by knitting metal thin wires, and has flexibility.

  The inner cable 320 protrudes from the front end opening of a cylindrical protrusion 318 </ b> A provided in the casing 318 and is accommodated in the cylindrical outer cable 322. One end portion of the outer cable 322 is fixed to the back surface side of the bottom portion 300 </ b> A of the box body 300 by a flange portion 324. The outer cable 322 is a cylindrical member made of synthetic resin and has flexibility.

  The outer cable 322 serves as a guide member for moving the inner cable 320 in the axial direction. When the inner cable 320 moves in the axial direction at the one end of the outer cable 322, the outer cable 322 (and the inner cable 322). 320), the inner cable 320 protruding from the other end of the outer cable 322 moves by the same amount in the axial direction (however, there is a loss in the amount of movement due to the material).

  That is, the outer cable 322 and the inner cable 320 have the same structure as a brake wire that connects a bicycle brake handle and a brake pad. Hereinafter, the outer cable 322 and the inner cable 320 are collectively referred to as a “wire transmission mechanism 326”.

  As shown in FIG. 7, the wire transmission mechanism 326 is disposed while bending the in-machine space of the image forming apparatus 110, and the other end is the position where the density sensor 155 is disposed. That is, the wire transmission mechanism 326 is routed in the apparatus regardless of the relative positional relationship between the paper feed tray 124 and the density sensor 155 and regardless of the configuration of the space path between them.

  The density sensor 155 is attached to the moving plates 328 and 330, respectively. The moving plates 328 and 330 are parallel to each other, and their longitudinal directions are arranged along the conveyance width direction. Further, teeth 328A and 330A are formed on the moving plates 328 and 330, and the teeth 328A and 330A are opposed to each other with a predetermined interval.

  A gear 332 is interposed between the moving plates 328 and 330, and the rotating shaft is rotatably supported by a base portion (not shown) in the machine while meshing with both the tooth portions 328A and 330A.

  A take-up reel 334 is coaxially attached to the gear 332. The take-up reel 334 rotates with the gear 332.

  The other end of the inner cable 320 is fixed to the outer periphery of the take-up reel 334. For this reason, the inner cable 320 is configured to be wound or pulled out by the take-up reel 334 depending on the rotation direction of the take-up reel 334.

  The inner cable 320 protrudes from the other end of the outer cable 322. The distal end portion of the outer cable 322 is fixed to a base portion (not shown) in the machine.

  As a result, the movement of the guide plates 302 and 304 (see FIGS. 5 and 6A) is transmitted to the moving plates 328 and 330 via the inner cable 320. As a result, the density sensor 155 attached to each of the movement plates 328 and 330 moves in the conveyance width direction without moving the center position (the movement amount is the same).

  Here, since the movement of the guide plates 302 and 304 (see FIGS. 5 and 6A) corresponds to the size (width direction dimension) of the recording paper P, the position of the density sensor 155 is naturally the recording paper P. As shown in FIG. 8, the position of the density sensor 155 (see FIG. 8A) on a relatively large size recording sheet (for example, A3 size) P is relatively small. The position of the density sensor 155 (see FIG. 8B) on the size recording paper (for example, postcard size) P is in the vicinity of both ends of the recording paper P in the width direction. In FIG. 8, the recording paper P in the paper feed tray 124 and the density sensor 155 are shown at the same time, but this does not show the actual relative positional relationship, but shows the virtual positional relationship. It is.

  The operation of this embodiment will be described below.

  First, the flow of misalignment correction using the density sensor 155 will be described.

  FIG. 9 is a flowchart of basic processing relating to color misregistration correction that is executed at a regular time such as when the number of processed sheets reaches a preset number, and at an irregular time such as when some error occurs. It is a flowchart which shows.

  As shown in FIG. 9, in order to measure the current color misregistration amount, a position detection pattern 153 is formed on the conveying belt 150 via the photosensitive drum 116 (pattern drawing in step 200), and this position detection pattern is used. The pattern 153 is detected by the density sensor 155 (sensor reading in step 202), the amount of color misregistration is calculated based on the detection data of the density sensor 155 (calculation in step 204), and the result of color misregistration is determined (step 206). Color misregistration result determination).

  Here, in the next step 208, light beam output timing correction data is generated, and in the next step 210, a color misregistration correction operation is finally performed (correction execution).

  Here, as shown in FIG. 5, the paper feed tray 124 of the present embodiment includes guide plates 302 and 304 that are movable in the width direction within the box 300, and the width of the recording paper P to be loaded. By moving according to the dimensions, the width direction is reliably guided.

  The guide plates 302 and 304 are moved in the axial direction of the inner wire 320 by the wire transmission mechanism 326 shown in FIG. 6 and transmitted to the moving plates 328 and 330 to which the concentration sensor 155 shown in FIG. 7 is attached.

  For this reason, the density sensor 155 moves by the same amount as the movement amount of the guide plates 302 and 304. In other words, the density sensor 155 is disposed in the vicinity of both ends in the width direction of the recording paper P regardless of the size of the recording paper P loaded in the paper feed tray 124 (see FIG. 8).

  FIG. 8A shows a case where a relatively large recording paper P is loaded into the paper feed tray 124. The guide plates 302 and 304 move relatively outward in accordance with the width dimension of the recording paper P, and the density sensors 155 are positioned at both ends in the width direction of the recording paper P correspondingly.

  Since the density sensor 155 is located at both ends, the positional deviation in the main scanning direction is dispersed to the maximum and is within the allowable error range. On the recording paper P, reference colors (for example, K (black) color), comparative colors (C (cyan) color, M (magenta) color, and Y (yellow) color) are used for confirmation of alignment. Two color alignment marks M1 and M2 of any one color)) are provided.

  Here, when a relatively small size recording paper P is loaded in the paper feed tray 124 and the density sensor 155 is fixed (the state shown in FIG. 8A), a range in which the positional deviation in the main scanning direction is unnecessary. Since it is distributed over an area unrelated to the recording paper P, there may be an error in the central portion of the recording paper P that may exceed the allowable range.

  On the other hand, in the present embodiment, when a relatively small size recording paper P is loaded in the paper feed tray 124, the guide plates 302 and 304 are moved to the small size as shown in FIG. It moves in accordance with the recording paper P. As a result, the density sensor 155 moves from the imaginary line position in FIG. 8B to the solid line position by the action of the wire transmission mechanism 326.

  That is, the density sensor 155 is located in the vicinity of both ends of the width dimension of the recording paper P. By performing misregistration correction at the position of the density sensor 155, misregistration in the main scanning direction is maximally dispersed within the range of the recording paper P, and an allowable error range is obtained. On the recording paper P, reference colors (for example, K (black) color), comparative colors (C (cyan) color, M (magenta) color, and Y (yellow) color) are used for confirmation of alignment. Two color alignment marks M1 and M2 of any one color)) are provided.

  That is, this embodiment pays attention to the fact that the guide plates 302 and 304 provided in the paper feed tray 124 are moved in accordance with the width dimension of the recording paper P loaded in the paper feed tray 124. The movement is transmitted to the moving plates 328 and 330 to which the concentration sensor 155 is attached using a mechanical operation amount transmission mechanism called a wire transmission mechanism 326. Since the inner wire 320 and the outer wire 322 are both flexible, the wire transmission mechanism 326 is arranged along the space in the machine regardless of the relative positions of the paper feed tray 124 and the density sensor 155. Just set up.

  In this embodiment, by moving one guide plate 302 (or 304), the other guide plate 304 (or 302) is moved in the same amount and in the opposite direction. According to this movement, Although the pair of concentration sensors 155 are also moved in the same direction and in the opposite directions using the wire transmission mechanism 326, the following modifications 1 to 3 can be considered.

(Modification 1)
As shown in FIG. 10, Modification 1 has a configuration in which a wire transmission mechanism 326 is provided for each of the concentration sensors 155 independently of the pair of guide plates 302 and 304.

(Modification 2)
As shown in FIG. 11, Modification 2 is configured such that one of the density sensors 155 is fixedly arranged and the position of the other density sensor 155 is moved. This corresponds to the case where the alignment reference of the recording paper P is at one corner.

(Modification 3)
As shown in FIG. 12, in the third modification, there are three density sensors 155, of which the central density sensor 155 is fixedly arranged, and only the left and right density sensors 155 are adjusted to the movement of the guide plates 320 and 304. Therefore, an independent wire transmission mechanism 326 is provided.

  In the present embodiment, the paper feed tray 124 has a single configuration. However, if a plurality of paper feed trays 124 are provided, the recording paper P to be loaded is not changed, and only the paper size is designated. It is also possible to select a paper feed tray destination to be taken out. In this case, it is preferable to load the most frequently used recording paper P into the paper feed tray 124 provided with the wire transmission mechanism 326.

  In this embodiment, the position detection pattern 153 has been described as an example. However, the present invention can also be applied to a pattern (density detection pattern) for so-called process control in which image density adjustment is performed.

  Furthermore, in this embodiment, the wire transmission mechanism 326 is used as the motion transmission member, but a transmission mechanism using the fluid pressure as a medium may be used.

  Further, in this embodiment, at least the main scanning direction is used, but by having a skew correction means (for example, deforming image data) or the like, a position shift in the sub-scanning direction is detected and the position is corrected. The color misregistration may be reduced.

  Furthermore, color misregistration correction may be performed when sheets of different paper sizes are loaded in the tray. As a result, the paper guide position is changed, it is determined that the density sensor 155 has moved, and the color misregistration correction is performed to reduce the color misregistration amount.

  In addition, please describe in the examples that color misregistration is corrected by changing the drawing position of other colors with respect to the reference color. This is because, since the detection sensor moves, it is less necessary to perform correction so as to match another color with the reference color using a certain color as a reference.

1 is a schematic diagram of an image forming apparatus according to the present embodiment. FIG. 6 is a plan view of a position detection pattern formed on a conveyance belt. 2 is a block diagram showing a control system for controlling the image forming apparatus according to the present embodiment. FIG. FIG. 6 is a front view of a sheet showing output timings of a horizontal synchronization signal and a vertical synchronization signal when forming an image. FIG. 3 is a perspective view of a paper feed tray unit according to the image forming apparatus of the present embodiment. (A) is a top view which shows the structure of the bottom part back surface of the paper feed tray which concerns on this Embodiment, (B) is the VIB-VIB sectional view taken on the line of FIG. 6 (A). It is a top view of the density sensor arrangement | positioning part which concerns on this Embodiment. 3 is a plan view virtually showing a positional relationship between a density sensor and a recording sheet. FIG. It is a flowchart which shows the flow of position shift correction control by a density sensor. FIG. 10 is a plan view showing a structure of a paper feed tray to which a wire transmission mechanism is attached according to Modification 1 of the present embodiment. FIG. 10 is a plan view illustrating a structure of a paper feed tray to which a wire transmission mechanism is attached according to Modification 2 of the present embodiment. FIG. 10 is a plan view illustrating a structure of a paper feed tray to which a wire transmission mechanism is attached according to a third modification of the present embodiment.

Explanation of symbols

P Paper 10 Microcomputer 12 Non-volatile memory 14 Image data development circuit 16 ROS control unit 20 Optical scanning device 23 Polygon mirror 25 Reflecting mirror 110 Image forming device (image forming means)
110A Side wall 111 (A, B, C, D) Developer 116 Photoconductor drum 118 Charging roll 120 Process cartridge 122 Erase lamp 124 Paper feed tray (tray)
126 Pickup roll (recording paper sending means)
128 transport roll 130 registration roll 132 paper transport path 146, 148 tension roll 150 transport belt 152 transfer roll 153 position detection pattern 154 suction roll 155 density sensor (position detection sensor)
156 Fixing device 158 Discharge roll 160 Discharge tray 166 Control unit 167 Image formation control unit (adjustment execution means)
170 UI
300 Box 302, 304 Guide plate 300A Bottom 300B, 300C Long hole 306, 308 Plate 310, 312 Gear plate 310A, 312A Tooth 314 Gear 316 Winding reel 318 Casing 316A, 316B Flange plate 316C Winding portion 320 Inner cable ( Motion transmission member)
318A Protruding part 322 Outer cable (motion transmission member)
324 Flange 326 Wire transmission mechanism (motion transmission member)
328, 330 Moving plate 328A, 330A Tooth part 332 Gear 334 Take-up reel

Claims (2)

A deflector for deflecting light output from the optical scanning unit and a plurality of image forming units for forming an image on an image holding body that moves in a sub-scanning direction that intersects the main scanning direction by the deflected scanning light. An image forming unit that forms a single image on a recording sheet by superimposing images formed by a plurality of image forming units on each other;
A recording sheet sending unit that includes a tray for temporarily storing the recording sheet in the apparatus, and takes out the recording sheet from the tray based on an image forming instruction and sends the recording sheet to an image forming position in the image forming unit;
An operation transmitting member provided on the tray and serving as an operation amount linked to the movement of a guide plate that moves according to the width dimension of the recording paper;
A position detection pattern having a detection locus along the sub-scanning direction and formed on the detection locus by the image forming unit and capable of recognizing at least position information in the main scanning direction is detected. A position detection sensor capable of moving in the width direction of the recording paper according to the operation;
A misalignment adjustment execution means for performing misalignment adjustment based on the position detection pattern detected by the position detection sensor;
An image forming apparatus. The motion transmission member includes a flexible cylindrical outer cable, and a flexible inner cable accommodated in the outer cable and movable in the axial direction along the curvature of the outer cable,
The image forming apparatus according to claim 1, wherein one end portion of the inner cable receives a moving force of the guide plate, and the other end portion transmits the moving force to the sensor.

Images