JP4457736B2 - Image forming apparatus - Google Patents

Description

  The present invention accommodates a large-capacity transfer material called LCT (Large Capacity Tray) or PFU (Paper Feed Unit), and removes a paper feeding auxiliary means that can feed paper according to an image forming process. The present invention relates to an image forming apparatus such as a copying machine or a printer that can be used.

  In general, an image forming apparatus such as a copying machine or a printer includes one or more trays for storing transfer materials such as paper.

  In addition, the image forming apparatus described above integrates externally an option such as LCT that can store a large amount of transfer material or, in other words, PFU that is used in a manner in which several layers of LCT are stacked. It is comprised so that it can respond to.

  It should be noted that such a sheet feeding auxiliary means such as LCT is used by attaching it externally to the image forming apparatus main body. The transfer material sent from the paper feeding auxiliary means is not inside the apparatus main body. In this transport path, the attachment position of the paper feeding auxiliary means is aligned with the transport path in the apparatus main body so that it can move within a predetermined width defined as an allowable range for control. Consideration should be given so that the finished image occupies an appropriate position on the transfer material and an image-formed product having a good appearance can be obtained.

  However, it is extremely difficult to configure or control the apparatus so that the transfer material always passes through the same position on the conveyance path due to various factors such as changes in environmental conditions or errors in the structure of the apparatus.

  Even in an image forming apparatus that does not have a paper feed assist unit, the transfer material is misaligned, but the position of the transfer material (specifically, parallel to the transfer direction of the transfer material) with respect to the design reference position. Even if there is a slight misalignment between the two sides of the direction or the position of the two side edges, a misregistration amount that can be controlled to produce a good-looking image formed product by appropriate correction, that is, an allowable range is arbitrarily determined. In the digital image forming apparatus, the positional deviation is corrected by controlling the writing position (see, for example, Patent Document 1 and Patent Document 2).

  Further, the positional deviation amount in the image forming apparatus is about 2 mm.

  Thus, the paper feeding auxiliary means is optionally manufactured separately from the image forming apparatus. For example, the position of the transfer material can be obtained only by being coupled to the image forming apparatus main body via a coupling means such as a screw. It was difficult to keep the amount of deviation within the allowable range as described above, and a positional deviation of 8 mm or more sometimes occurred.

  The position shift in the image forming apparatus main body is about 2 mm as described above, and the control system is set so that the image position correction is performed up to a position shift amount of about ± 2 mm, but the image position correction is not performed beyond that. Therefore, if the position is shifted by 8 mm due to the option connection, it is determined that the data is abnormal and is not corrected.

  The following methods are conceivable as methods for dealing with such problems.

Specifically, after the paper feeding auxiliary means is coupled to the image forming apparatus and integrated, the test chart toner image placed on the platen glass is output, and the transfer material on the transfer material parallel to the transport direction is output. Measure the size of the margin along the two sides, and correct the position of the paper feed assisting means with respect to the image forming apparatus main body so that the dimensions are equal to each other. This is a method of adjusting the position so that the transfer material can pass through the position on the conveyance path within the allowable range by repeatedly fixing until the transfer material is fixed.
Japanese Patent No. 2550558 JP 2000-33010 A

Patent Document 1 and Patent Document 2 perform image writing control corresponding to a positional shift in the main scanning direction of a transfer material fed from a tray in an image forming apparatus, and thus an image configured so that stable image formation can be performed. of it forming apparatus is disclosed, as LCT or PFU according to the present invention, the issues such as when binding to use in an image forming apparatus options for multiple functions (body) is taken into account Not.

  Also, the position adjustment method when the paper feed assisting unit is externally attached to the image forming apparatus takes a lot of time because the serviceman must measure the amount of deviation each time the test chart is output.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to reduce the time for adjustment work for attaching a paper feed assisting unit such as LCT or PFU to an image forming apparatus with a simple configuration. Another object of the present invention is to provide an image forming apparatus capable of reducing the mental burden on the adjuster by making it possible to know the degree of the adjustment stage without measuring it.

  The object of the present invention can be achieved by the following constitution.

(1)
An image forming apparatus comprising: an image forming apparatus main body including a transfer material supply unit; and a sheet feeding auxiliary unit externally attached via a coupling member in a coupling portion with the image forming apparatus main body. An index is provided on one of the coupling members provided on the forming apparatus main body and the paper feeding auxiliary means, and a scale in the main scanning direction is provided on the other coupling member, and the paper feeding is seen in the transfer material conveyance direction. A close contact type line sensor is provided on the transfer material conveyance path in the image forming apparatus main body at a position downstream of the attachment position of the auxiliary means, and the side edge of the transfer material conveyed from the paper supply auxiliary means is provided. The position is detected, and the output data of the contact type line sensor is used to determine the amount of positional deviation of the transfer material in the direction orthogonal to the conveying direction by the calculation means, and the amount of positional deviation is stored in the main body of the image forming apparatus. Displayed on the display unit kicked, using the index and scale in the display value and the coupling part, that the binding position of the paper feed auxiliary means for the image forming apparatus main body and the adjustable by moving in a main scanning direction A featured image forming apparatus.

  Since the misalignment of the transfer material sent from the paper feeding auxiliary means such as LCT and PFU from the conveyance reference position in the image forming apparatus main body is displayed, the degree of adjustment may be unexpectedly forgotten for some reason in the adjustment work. However, since it can be confirmed immediately, the mental burden is reduced and the adjustment time can be shortened.

  Further, if the LCT is provided with an index (for example, a line pattern) and a scale is provided on the apparatus main body side so as to be used for adjustment, the adjustment work can be performed more easily.

  Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 shows a digital electrophotographic copy that stocks a large amount of transfer material and can feed the stocked transfer material in accordance with an image forming process, with external paper feed auxiliary means according to the present invention. 1 is a schematic diagram illustrating a configuration of an image forming apparatus including the apparatus.

  In FIG. 1, an image forming apparatus 1 irradiates a laser beam modulated on an image carrier according to image data obtained by performing image processing on image information read by a reading unit A for reading an original image and the reading unit. Image forming means C including a developing device that develops the latent image formed and converts it into a toner image. A transfer material supply unit D having a plurality of pullable paper feed trays for storing and supplying a sheet-like transfer material that finally receives the image, a control means 1A for controlling the entire apparatus, and a liquid crystal touch panel And an operation unit 1B including a display unit and the like, and a sheet feeding auxiliary unit (hereinafter referred to as LCT for convenience) that can store and feed a large amount of transfer material.

  In the following description, the term “image forming apparatus” may refer to a configuration including LCT. For example, when it is preferable to express the image forming apparatus separately from LCT, it is referred to as an image forming apparatus main body.

  An automatic document feeding means E for automatically conveying the document is provided above the reading means A, and the documents 10 placed on the document placing table 11 are separated one by one by a separating means (without reference numerals) according to the image forming process. The image is read through a reading position 13 a corresponding to the lower part of the document conveying roller 12 in the process of being separated by the conveying means including the document conveying roller 12.

  The read original 10 is further conveyed downstream by a conveying unit including an original conveying roller 12 and is discharged onto an original discharge tray 14.

  Image reading is performed by reading means A having an optical system, which will be described later.

  When the original 10 has images on both sides, and when reading the double-sided images, the periphery of the original conveying roller 12 is again set so that the back side of the original 10 on which the first side is read is outside. Then, it is guided to the reading position 13a, read by the reading means A as described above, and then discharged onto the document discharge tray 14.

  The automatic document feeding means E is of a retractable type so that an image can be formed by placing a document on the platen glass 13 by manual operation. This is done by moving a part of the optical system.

  The reading means A includes a first mirror unit 15 having an illumination lamp and a first mirror, a second mirror unit 16 having a second mirror and a third mirror arranged in a V shape, and the third mirror. The projection lens 17 fixed on the reflected light path and the image sensor CCD as a line sensor are included.

  For image reading, the first mirror is fixed below the image reading position 13a for the document 10 fed by the automatic document feeding means E, and at a predetermined distance from the first mirror unit. While the second mirror unit 16 is fixed in position, the reading of the original 10 placed on the platen glass 13 is performed by using the first mirror unit 15 and the second mirror unit 16 at 2: This is done by moving in the same direction (left to right in the figure) at a speed ratio of 1.

  The read image is formed on the light receiving surface of the image sensor CCD through the projection lens 17.

  The optical image formed on the image sensor CCD is sequentially photoelectrically converted into an electrical signal (luminance signal), and further subjected to processing such as A / D conversion, density conversion, and filter processing.

  Then, exposure based on the processed image data (image information) is performed on the image carrier 21 by the writing unit B.

  The exposure optical system constituting the writing means B uses a laser diode (not shown) as a light source, and is composed of a polygon mirror 31, an fθ lens 34, a cylindrical lens 35, reflection mirrors 32, 33, and the like. Is made.

  Reference numeral Ao indicates an image exposure position, and sub-scanning is performed by rotation of the image carrier 21.

  The image forming unit C includes an image carrier 21 (hereinafter referred to as a photoreceptor) made of a drum-shaped photoreceptor, and a charger 22, a developing device 23, and a transfer unit provided along the outer periphery of the photoreceptor 21. 24, a separator 25, a cleaning device 26, a PCL (precharge lamp) 27 as a light neutralizing means, and the like.

  The photoconductor 21 is formed by coating a photoconductive compound on a drum base. For example, an organic photoconductor (OPC) is preferably used and is driven to rotate in the clockwise direction shown in the drawing.

  The electrostatic latent image is formed by sequentially performing exposure based on image data on the surface of the photoreceptor 21 after being uniformly charged by the charger 22 as described above.

  The electrostatic charge latent image formed on the photoreceptor 21 is reversely developed by contact development of a two-component developer including a magnetic carrier and a non-magnetic toner resulting from the operation of the developing device 23, and converted into a toner image. .

  The transfer material supply unit D is a sheet feeding unit 41 (A), 41 (B), 41 that accommodates transfer materials (for example, sheet-shaped plain paper, hereinafter referred to as sheets) P having different sizes. (C) and a manual paper feeding unit 42 that manually feeds the paper to the side. The sheet P selected from any of these is known as a feed roller (paper feed roller), a separation roller, or the like. The sheet is fed from the sheet feeding unit by the means, conveyed along the conveying path 40 by the guide roller pair 43, reaches the registration roller pair 44, and is re-supplied as the registration roller pair 44 starts rotating. It is conveyed toward the transfer region via the conveyance path 47 to be formed and the pre-transfer roller pair 43a.

  The toner image formed on the photoreceptor 21 is transferred onto the sheet P by the action of a transfer device (transfer means) 24 provided in the transfer area, and then receives the action of a separator (separation means) 25 to receive the photoreceptor. 21, and is transported toward the fixing device 50 by the transport unit 45.

  The fixing device 50 includes a fixing roller 51 and a pressure roller 52. When the sheet P passes between both rollers, heating and pressure are applied to melt and fix the toner on the sheet P. .

  The sheet P on which the toner image is formed is discharged to a discharge tray F through a pair of discharge rollers 53 and 55.

  Reference numeral 60 denotes sheet reversing means, which is used, for example, when the sheet P is discharged with the surface on which the toner image is formed facing down.

  That is, when discharging with the surface on which the toner image is formed facing down, the gate 54 is set to the state of the solid line shown in the figure by a solenoid (not shown), and the fixed sheet P is transferred to the sheet reversing means 60. Is guided to the reverse conveyance path 600 side through the pair of reverse rollers 601 and stops when the rear end of the sheet P reaches the position in front of the reverse roller pair 601, and then the reverse roller pair 601 is reversed. The sheet P can be sent out along the lower surface of the gate 54 and discharged through the discharge roller pair 55.

  Reference numeral 70 denotes sheet reversing means for reversing the front and back of the sheet P when forming a toner image on both sides of the sheet P. Here, only a general description of the configuration and operation is given.

  When image formation is performed on both sides of the sheet P, the sheet P with the toner image formed on the upper surface is reversed by the reversing roller pair 601, the conveying roller pairs 602 and 603, and the reversing roller pair 701 constituting the sheet reversing unit 70. By passing the conveyance path 600 and guiding it to the reverse conveyance path 700, the conveyance is stopped when the trailing edge of the sheet P comes before the reverse roller pair 701, and then the reverse roller pair 701 is rotated in the opposite direction. The sheet is switched back and reversed, and is guided to the same conveyance path 47 as the sheet P conveyed from the sheet feeding unit 41 (A) or the like via the conveyance path 703, and the same toner image as that formed on the first surface is formed. This can be achieved by transferring and fixing.

  On the opposite side of the image forming apparatus main body from the paper discharge tray F is an externally attached LCT 8, and P 1 indicates a sheet stacked on a built-in lift table 800.

  The lift 800 is a lift drive means comprising pulleys 801 and 803 fixed to a frame constituting the LCT and a wire 805 suspended on both pulleys, and the wire 805 is fixed to the lift. The vertical movement of the lifting platform is made possible via the coupling part.

  The lifting platform driving means is provided on both sides of the lifting platform and uses one motor M as a drive source.

  In the sheet feeding control using the LCT, a program provided in the LCT ROM is called by a command from the control means 1A provided in the image forming apparatus main body, and the program is controlled under the control of the control means 1A. Is executed by executing.

  Reference numeral 810 denotes a paper feed roller, and 820 denotes a transport roller. When paper is fed, a sheet P1 separated into one sheet is transported in a substantially horizontal direction at a predetermined height, and then an intake port (see reference) provided in the image forming apparatus main body. The sheet is conveyed toward the guide roller pair 43 via the unsigned).

830 is a coupling member, is fixed to the frame of the bottom plate side of the LCT8.

  The top of the coupling member 830 is horizontal, and the lower surface thereof is aligned with the upper surface of the screw hole member 100 provided at the bottom of the image forming apparatus main body, or known adjusting means provided at the leg. Configured to align by adjusting.

  Such a coupling member 830 and the screw hole member 100 are provided at two locations in the front and back direction of the paper surface.

  When attaching the LCT to the main body of the image forming apparatus, the LCT 8 is moved in the main scanning direction (the length of the photoconductor 21 and indicates the front and back direction of the paper surface in the drawing). When the coupling member 830 and the screw hole member 100 are completely coupled when they are within an allowable range on the inner conveyance path, the integration of the image forming apparatus main body 1 and the LCT 8 is completed.

  FIG. 2 is a plan view schematically showing a configuration of a coupling portion between the coupling member 830 and the screw hole member 100 in FIG.

  In the drawing, the same reference numerals are given to the already-explained members (means).

  In the present embodiment, there are two connecting portions. Each screw hole member 100 provided in the image forming apparatus main body has three screw holes 110 and a line mark 120 formed on the center line of the screw hole 110 at the center.

  On the other hand, the coupling member 830 provided in the LCT 8 has a hole 840 having a dimension longer than the dimension formed by both ends of the three screw holes 110 and a scale 850.

  The hole 840 is used to insert a screw (not shown) to be coupled to the screw hole 110, thereby integrating the image forming apparatus 1 and the LCT 8, and the scale 850 is used for the LCT. It is used for adjustment work to obtain the desired position by moving in the main scanning direction (left and right direction in the figure).

  The scale 850 is composed of lines drawn in units of 1 mm. When the coupling member 830 is overlapped with the screw hole member 100, the line mark 120 and the line of the scale 850 can be visually recognized.

  In the adjustment work, the coupling member 830 and the screw hole member 100 are vertically stacked, the line mark 120 and the line 850a at the center of the scale 850 are aligned, and temporarily fixed with screws, and then the sheet P1 is used for the image. In this case, the amount of positional deviation in the main scanning direction of the sheet P1 with respect to the reference position is obtained by calculation, and is digitally displayed on the display unit of the operation unit 1B.

  For example, the display can indicate how many mm of minus (−) or plus (+). After confirming that, the adjustment operator loosens the screw and moves the LCT 8 by a predetermined amount in a predetermined direction. By using 850 to move and fixing with screws again, the alignment of the LCT 8 with respect to the image forming apparatus main body 1 is completed.

  3 and 4 are diagrams schematically showing the relationship between the positional deviation of the sheet P1 during adjustment and a sensor for detecting the positional deviation amount. FIG. 3 is a side view of the main part, and FIG. It is a top view.

  In FIG. 3, reference numeral 9 denotes a sheet position deviation detection device (hereinafter referred to as a sheet detection device), which is downstream of the LCT attachment position, that is, in the image forming apparatus main body as viewed in the conveyance direction of the sheet P1. Provided on the road.

  The sheet detection device 9 includes a light emitting element 900 composed of LEDs, a condensing lens 903 that collects light emitted from the light emitting element 900 reflected by the sheet P1, and a pixel sensor 905 that receives the collected light. including. Reference numeral 910 indicates a case in which a member or element such as the light emitting element is incorporated.

  As shown in FIG. 4, the light emitting element 900, the pixel sensor 905, and the like are installed in a direction orthogonal to the conveyance direction of the sheet P1, and the installation positions extend left and right with the reference position S therebetween.

  In other words, the sheet P1 is installed so as to cover a predetermined range in the main scanning direction in consideration of the positional deviation amount before adjustment, on which one side end (side) of the sheet P1 will pass.

  The side edge of the plain sheet indicated by P1 is at the reference position, and the position of the sheet indicated by hatching is shifted to the minus side with respect to the reference position, for example.

  Note that the light emitting elements 900 are arranged in a line at an appropriate interval, and the pixel sensor 905 has a configuration in which contact line sensors (hereinafter simply referred to as sensors) having a detection resolution of 0.125 mm are arranged in a line. .

  FIG. 5 is a schematic electrical block diagram relating to the detection and display of sheet misalignment, and FIG. 6 is a block diagram showing an embodiment in which specific numerical values are taken in.

  With reference to FIGS. 3 and 4, the detection of the positional deviation amount of the sheet P1 and the display of the deviation amount will be described with reference to FIGS. When the detected position is reached, a clock from the sensor drive clock generator 950 is input to the sensor 905.

  The sensor 905 detects light reflected by the sheet P, and is synchronized with the input clock from the center (a sensor placed corresponding to the position through which the designed sheet center passes) to the side edge of the sheet P. Outputs a sawtooth pulse.

  The output of the sensor 905 corresponding to the region beyond the side edge of the sheet P is 0V. On the other hand, the sawtooth pulse is smoothed, amplified, converted to a 12V output, and input to the comparator 952.

  The counter 954 compares the predetermined value (threshold value) by the comparator 952 and the output of the sensor with one side edge of the sheet (perpendicular to the conveying direction) from the center in a range showing an output higher than the threshold value. The edge of the sheet in the direction of the sheet) is counted, and the sheet passing position of the sheet side edge with respect to the reference position is detected.

  For example, when the sheet P1 is A4 size, data 1130 is detected from the detection resolution of the sensor and the count value.

  The data is input to the comparison calculation means 956 and compared with the design value data read from the LCT8 ROM when using the A4 sheet.

  For example, if the design value data is data of 1090, the data difference 40 is obtained, and since one data is 0.125 mm which is the detection resolution of the sensor, it is required that there is a positional deviation of 5 mm.

  The calculation result is, for example, minus 5 mm at the position display position on the display unit of the operation unit 1B (5 mm on the right side in the main scanning direction in the figure with respect to the reference position. Digital display is made.

  The subsequent adjustment work can be completed easily and in a short time by completing the method described with reference to FIG. 2, and the adjustment work for setting the sheet positional deviation amount within an allowable range can be completed. Anxiety when you have forgotten the amount of misalignment because you can see how much the adjustment stage is without measuring it, and in the state where it is displayed, you can always check the display. The mental burden on the operator can be reduced.

  The present invention is not limited to the above-described embodiment. For example, the formation of line marks and scales for position alignment may be reversed, and the end side of the screw hole member is used as the line mark. You can also

  Further, when the second frame body, which is built in the LCT frame body and includes a lifting platform for stacking and storing sheets, is movable in the main scanning direction, the LCT image is displayed. After fixing at a predetermined position of the forming apparatus, the second frame body may be moved in the main scanning direction to adjust the positional deviation. In this case, the above-described line mark and scale are the LCT It will be provided on the frame and the second frame.

Furthermore, the scale can be marked at an appropriate interval (for example, 2 mm), and the holes 840 can be provided for each screw. The degree of freedom is wide.

1 is a schematic diagram illustrating a configuration of an image forming apparatus including a digital electrophotographic copying apparatus. It is a top view which shows typically the structure of the coupling | bond part of the member for a coupling | bonding in FIG. 1, and a screw hole member. FIG. 5 is a side view of a main part schematically illustrating a relationship between a positional deviation of a sheet at the time of adjustment and a sensor for detecting a positional deviation amount. 6 is a plan view of a principal part schematically showing a relationship between a positional deviation of a sheet at the time of adjustment and a sensor for detecting a positional deviation amount. FIG. FIG. 6 is a schematic electrical block diagram relating to detection and display of a positional deviation of a sheet. It is a block diagram which shows the Example which took in a concrete numerical value.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 100 Screw hole member 120 Line mark 8 Paper feed auxiliary means (LCT, PFU)
830 Coupling member 850 Scale 9 Sheet detection device 900 Light emitting element 905 Pixel sensor

Claims (1)

An image forming apparatus comprising: an image forming apparatus main body including a transfer material supply unit; and a sheet feeding auxiliary unit externally attached via a coupling member in a coupling portion with the image forming apparatus main body. An index is provided on one of the coupling members provided on the forming apparatus main body and the paper feeding auxiliary means, and a scale in the main scanning direction is provided on the other coupling member, and the paper feeding is seen in the transfer material conveyance direction. A close contact type line sensor is provided on the transfer material conveyance path in the image forming apparatus main body at a position downstream of the attachment position of the auxiliary means, and the side edge of the transfer material conveyed from the paper supply auxiliary means is provided. The position is detected, and the output data of the contact type line sensor is used to determine the amount of positional deviation of the transfer material in the direction orthogonal to the conveying direction by the calculation means, and the amount of positional deviation is stored in the main body of the image forming apparatus. Displayed on the display unit kicked, using the index and scale in the display value and the coupling part, that the binding position of the paper feed auxiliary means for the image forming apparatus main body and the adjustable by moving in a main scanning direction A featured image forming apparatus.

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