JP2019155754A - Image forming device and program - Google Patents

Abstract

To provide an image forming device and a program for discharging a sheet as a blank without stopping conveyance of the sheet when data to be printed is to be printed on the sheet other than a predetermined sheet.SOLUTION: An image forming device includes: a plurality of image holding bodies for holding toner images corresponding to a plurality of color components; an intermediate transfer body for holding the toner images laid one on another in a sequential order as a primary transfer from the plurality of image holding bodies; secondary transfer means for secondarily transferring the toner image on the intermediate transfer body to a sheet; conversion means for converting printing data to image data for each predetermined color component except a black color of the plurality of color components when the printing data is received as data to be printed onto a predetermined sheet; and moving means for moving the image holding body corresponding to a predetermined color component to a position where it does not come in contact with the intermediate transfer body by relative movement with respect to the intermediate transfer body when a sheet fed from a paper feeding part is a sheet other than the predetermined sheet.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an image forming apparatus and a program.

  In recent years, an image forming apparatus has been proposed in which confidential information is prevented from being printed and leaked outside the company or the like (see, for example, Patent Document 1).

  An image forming apparatus described in Patent Document 1 includes an image reading unit that reads a document, and cyan (C), magenta (M), yellow (Y), and black (K) formed based on image data of each color. Each color image holding body for holding each color toner image, an intermediate transfer belt for holding the toner image primarily transferred from each image holding body, and paper feeding for storing security paper or plain paper in which a magnetic material is embedded A secondary transfer unit that secondary-transfers the toner image on the intermediate transfer belt onto the sheet conveyed from the sheet feeding unit, and detection that detects that the sheet fed from the sheet feeding unit is a security sheet If the device and the detection device can detect that the paper is security paper, the image forming process permission is output. If the detection device cannot detect that the paper is security paper, image formation is performed. And a signal determination circuit for the indication of physical stop.

JP 2017-90678 A

  Depending on the timing at which the paper is fed from the paper feed unit, the image forming process may not be stopped in time, and confidential information may be printed on plain paper and discharged. Further, if the paper fed from the paper feeding unit is not security paper, stopping the paper conveyance may cause a paper jam.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus and a program that, when printing target data is to be printed on a sheet other than a predetermined sheet, discharges the sheet as a blank sheet without stopping the sheet conveyance. is there.

[1] A plurality of image carriers that respectively hold toner images corresponding to a plurality of color components;
An intermediate transfer member for holding toner images sequentially stacked as primary transfer from the plurality of image carriers;
Secondary transfer means for secondary transfer of the toner image on the intermediate transfer member to a sheet;
Converting means for converting the print data into image data for each predetermined color component excluding black among the plurality of color components when print data is received as a print target on a predetermined paper;
When the sheet fed from the sheet feeding unit is a sheet other than the predetermined sheet, the image carrier corresponding to the predetermined color component is moved relative to the intermediate transfer body by the relative movement. An image forming apparatus comprising: a moving unit configured to be in a position not in contact with the intermediate transfer member.
[2] In the image carrier corresponding to the predetermined color component, the position in contact with the intermediate transfer member is a normal position.
The moving means contacts the intermediate transfer member with an image carrier corresponding to the predetermined color component when the paper fed from the paper feeding unit is a paper other than the predetermined paper. The image forming apparatus according to [1], wherein the image forming apparatus is moved relatively to a position where it is not.
[3] The image carrier corresponding to the predetermined color component is in a normal position where it does not contact the intermediate transfer member.
When the sheet fed from the sheet feeding unit is the predetermined sheet, the moving unit moves the image holding body corresponding to the predetermined color component to a position in contact with the intermediate transfer body. The image forming apparatus according to [1], wherein the image forming apparatus is moved relatively.
[4] The image forming apparatus according to any one of [1] to [3], further including a determination unit that determines whether or not the print data is to be printed on a predetermined sheet.
[5] An operation unit that receives a user operation is further provided,
The determination unit according to [4], wherein the determination unit determines that the print data is an object to be printed on a predetermined sheet when a print instruction for the print data is received by an operation on the operation unit. Image forming apparatus.
[6] When the determination unit receives a print instruction for the print data from an external device, the determination unit determines whether the print data is to be printed on a predetermined sheet based on information included in the print instruction. The image forming apparatus according to [4], wherein the determination is made.
[7] The print instruction includes storage location information indicating a storage location of the print data,
The determination unit according to [6], wherein when the storage location information is included in the storage location information stored in advance, the print data is determined to be printed on a predetermined sheet. Image forming apparatus.
[8] The determination unit determines whether or not the print data is to be printed on a predetermined sheet before the sheet is fed from the sheet feeding unit. The image forming apparatus according to any one of the above.
[9] The image forming apparatus according to any one of [1] to [8], wherein the paper feeding unit feeds paper before the primary transfer.
[10] The print data is confidential information,
The image forming apparatus according to any one of [1] to [9], wherein the predetermined sheet is a sheet provided with a magnetic body.
[11] The predetermined paper is a paper on which one side is printed, or a paper on which both sides are not printed,
The sheet other than the predetermined sheet is a sheet on which the other side of the sheet on which the one side is printed is fed as a printing target surface, or a sheet on which both sides are printed. The image forming apparatus according to any one of [1] to [9].
[12] A plurality of image holders that respectively hold toner images corresponding to a plurality of color components, an intermediate transfer member that holds toner images sequentially stacked as a primary transfer from the plurality of image holders, and the intermediate transfer A secondary transfer unit that secondary-transfers the toner image on the body to a sheet;
Conversion means for converting the print data into image data for each color component other than black among the plurality of color components when print data is received as a print target on a predetermined paper;
When the sheet fed from the sheet feeding unit is a sheet other than the predetermined sheet, the image carrier corresponding to the predetermined color component is moved relative to the intermediate transfer body by the relative movement. A program for functioning as a moving means for making the position not in contact with the intermediate transfer member.

According to the first, fourth, and twelfth aspects, when the data to be printed is about to be printed on a sheet other than a predetermined sheet, the sheet can be discharged as a blank sheet without stopping the conveyance of the sheet. it can.
According to the second and third aspects of the present invention, when the data for plain paper is printed in black and white, the conveyance resistance of the intermediate transfer member is suppressed, and the conveyance speed can be increased.
According to the fifth aspect of the invention, the user can print a confidential paper document on a predetermined paper.
According to the sixth aspect of the present invention, it is possible to designate a printing target on a predetermined sheet from an external device.
According to the invention of claim 7, information having confidentiality can be managed by the storage location information.
According to the eighth aspect of the present invention, the printing on the predetermined paper is compared with the configuration for determining whether the print data is to be printed on the predetermined paper before the paper is fed. The processing time can be shortened.
According to the ninth aspect of the present invention, it is possible to shorten the processing time for printing on a predetermined sheet as compared with the configuration in which the sheet is fed after the primary transfer.
According to the invention of claim 10, a predetermined paper can be magnetically detected.
According to the eleventh aspect of the present invention, when a sheet on which the printing target surface is already printed is fed, unnecessary printing can be avoided.

FIG. 1 is a diagram illustrating a schematic configuration example of an image forming apparatus according to a first embodiment of the present invention. FIG. 2 is a schematic view of a main part for explaining the retract mechanism. FIG. 3 is a block diagram illustrating an example of a control system of the image forming apparatus. FIG. 4 is a table for explaining an example of the operation of the image forming apparatus according to the first embodiment. FIG. 5 is a flowchart illustrating an example of the operation of the image forming apparatus according to the first embodiment. FIG. 6 is a flowchart showing an example of the operation of the image forming apparatus according to the second embodiment of the present invention. FIGS. 7A and 7B are diagrams for explaining a modification example of the retract mechanism. FIG. 7A is a schematic view of a main part before retraction and FIG. 7B is after retraction.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, in each figure, about the component which has the substantially same function, the same code | symbol is attached | subjected and the duplicate description is abbreviate | omitted.

[Summary of embodiment]
The image forming apparatus according to the present embodiment includes a plurality of image holding bodies that respectively hold toner images corresponding to a plurality of color components, and an intermediate transfer that holds toner images sequentially stacked as primary transfer from the plurality of image holding bodies. Body, secondary transfer means for secondary transfer of the toner image on the intermediate transfer body to paper, and when print data is received as a print target on a predetermined paper, the print data is out of a plurality of color components Conversion means for converting into image data for each predetermined color component excluding black, and when the paper fed from the paper feeding unit is paper other than the predetermined paper, And a moving unit that moves the corresponding image carrier to a position that does not contact the intermediate transfer member by relative movement with respect to the intermediate transfer member.

  “Print data” includes, for example, data obtained by using a scan function of the image forming apparatus and data transmitted from an external apparatus. “Image data” is bitmap format data obtained by converting print data for print processing, for example, CMYK image data in which the color of each pixel is represented by a CMYK value. The “predetermined color component” is, for example, a color component that becomes black by overlapping toner images, but may be a color component that becomes a color other than black. The “plurality of image carriers” may be, for example, for cyan (C), magenta (M), yellow (Y), and black (K), and may include other colors.

  The “predetermined paper” is a specific paper such as a paper provided with a magnetic material as a representative example, but is not limited to a specific paper. “Print data as a print target on a predetermined sheet” is information having confidentiality as a typical example, but is not limited thereto. Information having confidentiality includes confidential documents, drawings, photographs, images, and the like. The confidential document may include a photograph, an image, and the like.

  “Relative movement” means both the case where the image carrier moves relative to the intermediate transfer member and the case where the intermediate transfer member moves relative to the image carrier.

  In the image forming apparatus configured as described above, when the sheet fed from the sheet feeding unit is a sheet other than a predetermined sheet, the image carrier corresponding to the predetermined color component is subjected to intermediate transfer. Since the toner image of a predetermined color component is not transferred to the intermediate transfer body, the blank sheet is discharged. When the paper fed from the paper feeding unit is a predetermined paper, the image holding body corresponding to the predetermined color component contacts the intermediate transfer body, and the toner image of the predetermined color component is A sheet that is transferred to the intermediate transfer member and printed with a color (for example, black) on which toner images of predetermined color components are superimposed is discharged.

[First Embodiment]
FIG. 1 is a diagram illustrating a schematic configuration example of an image forming apparatus according to a first embodiment of the present invention.

  The image forming apparatus 1 is a multifunction machine having a plurality of functions such as copying, printing, and scanning.

  The image forming apparatus 1 is provided with a substantially box-shaped casing 2, a controller 3 disposed in the casing 2, and a detachable unit at the bottom of the casing 2, and security paper or plain paper is used as the paper P. A paper feed tray 4A to be accommodated, a manual feed tray 4B that is detachably provided on the side surface of the housing 2, and first to third discharges that are disposed on the top of the housing 2 and from which printed paper P is discharged. Paper trays 5A to 5C (hereinafter, collectively referred to as “sheet discharge tray 5”). The security paper is an example of a predetermined paper. The paper feed tray 4A and the manual feed tray 4B are examples of a paper feed unit.

  In the image forming apparatus 1, a sheet conveyance path 6 is formed so as to extend from the sheet feed tray 4 </ b> A to the sheet discharge tray 5. The paper transport path 6 includes a take away path 60, a manual feed path 61, a registration path 62, a paper discharge path 63, and a duplex printing path 64.

  The take away path 60 and the manual feed path 61 are paths that guide the paper P taken from the paper feed tray 4 </ b> A to the registration path 62. The registration path 62 is a path for forming an image on the paper P. The paper discharge path 63 is a path that guides the image-formed paper P to the paper discharge tray 5. The double-sided printing path 64 is a path that guides the paper P turned back in the paper discharge path 63 to the registration path 62 again. The paper discharge path 63 includes a first paper discharge path 63a that discharges to the first paper discharge tray 5A, a second paper discharge path 63b that discharges to the second paper discharge tray 5B, and a third paper discharge tray. And a third discharge path 63c for discharging to 5B.

  In the paper conveyance path 6, a pickup roll 11 that takes the paper P from the paper feed tray 4 </ b> A into the takeaway path 60 one by one, a conveyance roll 12 that conveys the paper P taken in by the pickup roll 11, and a pickup roll 11. A security paper detection unit 13 that detects that the captured paper P is a security paper, an intermediate transfer belt 173 to which a toner image is primarily transferred, and a toner image on the intermediate transfer belt 173 are secondarily transferred to the paper P. A secondary transfer roll 14 and a fixing device 15 for fixing the toner image on the paper P are disposed. The intermediate transfer belt 173 is an example of an intermediate transfer member. The secondary transfer roll 14 is an example of a secondary transfer unit.

  The image forming apparatus 1 includes a paper transport mechanism 17 that transports the paper P along the paper transport path 6. The paper transport mechanism 17 includes a motor that rotationally drives the pickup roll 11, the transport roll 12, and the secondary transfer roll 14, and a drive circuit that drives the motor. The paper transport mechanism 17 includes a reversing unit 17 a that causes the paper P to pass through the duplex printing path 64 and reverses the paper P.

  The reversing unit 17 a switches the guide so that when the paper P exits the registration path 62, the paper P does not proceed to the paper discharge path 63 but proceeds to the duplex printing path 64. The guide guides the paper P to advance to the paper discharge path 63 by the spring force of the spring member, and guides the paper P to advance to the double-sided path 63 by the operation of the solenoid.

  In the image forming apparatus 1, an image forming unit 16 that forms an image is disposed above the paper feed tray 4 </ b> A in the housing 2.

  The image forming unit 16 includes an intermediate transfer belt 173 stretched around a drive roll 170, a backup roll 171, and a driven roll 172. The intermediate transfer belt 173 circulates and moves in the direction of the arrow in the drawing while being in contact with a later-described photosensitive drum.

  Further, the image forming unit 16 forms toner images of cyan (C), magenta (M), yellow (Y), and black (K) colors on the intermediate transfer belt 173, and the image forming units 160C, 160M, 160Y, and 160K. (Hereinafter, these are also collectively referred to as “image forming unit 160”).

  Each of the image forming units 160 is a photosensitive drum 161C, 161M, 161Y, 161K (hereinafter, collectively referred to as “photosensitive drum 161”) on which toner images of CMYK colors are formed, and a photosensitive member. A charger that uniformly charges the surface of the drum 161 and an exposure that forms an electrostatic latent image of each color of CMYK by irradiating the charged photosensitive drum 161 with exposure light modulated based on image data of each color of CMYK. And developing units 163C, 163M, 163Y, and 163K that form toner images on the surface of the photosensitive drum 161 by developing the electrostatic latent image with toner (hereinafter referred to as “developing unit 163” collectively). Also). Here, the photosensitive drum 161 is an example of an image carrier. Note that the photosensitive drum 161 may be a photosensitive belt.

  In addition, the image forming unit 160 has primary transfer rolls 162C, 162M, 162Y, and 162K (hereinafter collectively referred to as “the first transfer rolls 162C, 162M, 161Y, and 161K” on the opposite side of the photosensitive drums 161C, 161M, 161Y, and 161K with the intermediate transfer belt 173 interposed therebetween. Primary transfer roll 162 "), and a toner image on the surface of the photosensitive drum 161 is transferred to the intermediate transfer belt 173 by a pressure contact force and an electrostatic force in a nip region formed with the photosensitive drum 161. Among the components of the image forming units 160C, 160M, 160Y, and 160K, the components around the photosensitive drum 161 and the photosensitive drum 161 excluding the primary transfer rolls 162C, 162M, 162Y, and 162K are hereinafter referred to as a photosensitive drum unit. It is called 164C, 164M, 164Y, 164K.

  Further, the image forming apparatus 1 moves the CMY photosensitive drum units 164C, 164M, and 164Y other than K from the position where the photosensitive drums 161C, 161M, and 161Y are in contact with the intermediate transfer belt 173 to a position (retract position). A retract mechanism 18 is provided. The retract mechanism 18 will be described later with reference to FIG. The retract mechanism 18 is an example of a moving unit. CMY is an example of a predetermined color component.

(Configuration to detect security paper)
A magnetic material is embedded in the security paper. As the magnetic material, a magnetic material capable of generating a large Barkhausen effect, for example, an amorphous magnetic material having a diameter of 15 to 35 μm and a length of 15 to 25 mm can be used. The large Barkhausen effect is a phenomenon that causes periodic magnetization reversal when an oscillating magnetic field acts.

  The security paper detection unit 13 includes an excitation coil, an antenna, and a detection circuit. The exciting coil generates an oscillating magnetic field when supplied with AC power. When the security paper in which the magnetic material is embedded passes through the security paper detection unit 13, the amplitude of the oscillating magnetic field acting on the magnetic material increases. When the amplitude of the oscillating magnetic field reaches a threshold value, the magnetization of the magnetic material is periodically reversed. Happens. The magnetic body generates an electrical pulse that accompanies magnetization reversal. The detection circuit compares the waveform of the pulse received by the antenna with the waveform of the pulse stored in advance, and detects the security sheet according to the degree of coincidence between the two. When the security paper detection unit 13 detects the security paper, the security paper detection unit 13 transmits a detection signal to the paper determination unit 305.

(Print mode)
The image forming apparatus 1 has, for example, a “single-sided printing mode” for forming an image on one side of the paper P and a “double-sided printing mode” for forming an image on both sides of the paper P.

  Further, in the “single-sided printing mode” and the “double-sided printing mode”, the image forming apparatus 1 performs “backside discharge” in which the first printed surface is discharged as the back surface of the paper P, and the first printed surface is the front surface of the paper P. It is possible to specify “surface discharge” to be discharged.

  In the case of “reverse discharge” in the single-sided printing mode, the paper P is conveyed through the takeaway path 60 or the manual feed path 61, and the front surface is printed by the registration path 62, and the first discharge tray 5A or the second discharge tray. It is discharged to 5B.

  In the case of “front discharge” in the single-sided printing mode, the paper P is printed on the surface of the paper P through the same path as that in the case of “backside discharging” in the single-sided printing mode, and discharged to the third paper discharge tray 5C. .

  In the case of “reverse discharge” in the duplex printing mode, the paper P is conveyed through the takeaway path 60 or the manual feed path 61, the front surface is printed by the registration path 62, and then the paper P is turned back by the second paper discharge path 63b. Then, the paper P is reversed by passing through the double-sided printing path 64, the back side is printed by the registration path 62, and is discharged to the third paper discharge tray 5C.

  In the case of “front discharge” in the double-sided printing mode, when the paper P is a security paper, the back side is printed after the front surface of the paper P is printed through the same path as in the case of “reverse side discharge” in the double-sided printing mode. Then, the paper is discharged to the first paper discharge tray 5A or the second paper discharge tray 5B.

  In the image forming apparatus 1 configured as described above, when the CMYK color toner images are superimposed and primarily transferred onto the intermediate transfer belt 173 based on the CMYK color image data, the toner images are fed. Secondary transfer is performed on the paper P fed from the tray 4A. The toner image transferred to the paper P is fixed on the paper P by the fixing device 15, and then the paper P is discharged to the paper discharge tray 5.

(Configuration of retract mechanism)
FIG. 2 illustrates a state in which the CMY photosensitive drum units 164C, 164M, and 164Y are moved to the retract position. The retract mechanism 18 controls the CMY photosensitive drum units 164C, 164M, and 164Y to a position where the photosensitive drums 161C, 161M, and 161Y do not contact the intermediate transfer belt 173 (retract position) under the control of the retract mechanism control unit 305. ). In the present embodiment, the positions where the CMY photosensitive drums 161C, 161M, and 161Y are in contact with the intermediate transfer belt 173 are normal.

  The retract mechanism 18 includes, for example, a spring member that presses the CMY photosensitive drum units 164C, 164M, and 164Y against the intermediate transfer belt 173 side, a cam, a motor that rotates the cam, and a drive circuit that drives the motor. In the normal state, the retraction mechanism 18 presses the CMY photosensitive drum units 164C, 164M, and 164Y against the intermediate transfer belt 173 side by the spring force of the spring member, and does not transfer the CMY toner image to the intermediate transfer belt 173. Then, the motor is driven by the drive circuit to rotate the cam, and the CMY photosensitive drum units 164C, 164M, 164Y are moved to the retracted position against the spring force of the spring member.

  FIG. 3 is a block diagram illustrating an example of a control system of the image forming apparatus 1. The controller 3 of the image forming apparatus 1 is connected to the above-described security paper detection unit 13, paper transport mechanism 17, and retract mechanism 18, and is further connected to an operation display unit 7, an image reading unit 8, and a communication unit 9. A terminal device 20 operated by a user and a document server 21 for managing documents are connected to the communication unit 9 via a network 19. The operation display unit 7 is an example of an operation unit. The terminal device 20 is an example of an external device.

  The image forming apparatus 1 executes a copy job or a print job as a print job. A copy job is a job that causes the image forming unit 16 to execute print processing using data (hereinafter also referred to as “scan data”) output from the image reading unit 8 to the control unit 30. The print job is a job that causes the image forming unit 16 to execute print processing using data transmitted from the communication unit 9 to the control unit 30.

  The operation display unit 7 includes a touch panel display in which a touch panel is superposed on a display unit such as a liquid crystal display, displays a display screen on the display unit, and accepts an operation from the user to the touch panel. Note that the operation display unit 7 may include an input unit and a display unit that are provided independently.

  The image reading unit 8 reads a document image from a document and generates scan data (for example, RGB image data). The image reading unit 8 includes an automatic document feeder provided on a document table and a scanner. A document image is optically read from a placed document or a document sent by an automatic document feeder. The image reading unit 8 transmits the generated scan data to the controller 3. The RGB image data is image data in which the color for each pixel is represented by an RGB value.

  When the user activates the printer driver and specifies the file name of the document to be printed, the terminal device 20 stores the corresponding document data from the document server 21 based on the specified file name and the storage location of the document data. Get information. The printer driver converts the document data into PDL (page description language) data to be printed, and transmits the print job to the image forming apparatus 1 via the network 19 together with the storage location information of the PDL data and the document data. Note that a user ID for identifying a user who operates the terminal device 20 may be set in the printer driver, and the confidential document may be stored in a folder dedicated to the confidential document by the document server 21 corresponding to the user ID.

  For example, the document server 21 stores confidential documents in folders dedicated to confidential documents, and stores documents other than confidential documents in other folders. The document server 21 transmits and receives files between the terminal device 20 and the image forming apparatus 1 by HTTPS (Hyper Text Transfer Protocol Security) communication. The HTTPS communication performs encrypted communication in which communication contents are concealed using, for example, an SSL (Secure Sockets Layer) protocol. When accessed from the terminal device 20, the document server 21 transmits document data corresponding to the file name and storage location information of the document data to the terminal device 20 by HTTP communication.

  The controller 3 includes a control unit 30 that controls each unit of the image forming apparatus 1 and a storage unit 31 that stores various types of information.

  The control unit 30 includes a CPU (Central Processing Unit), an interface, and the like. The CPU functions as the accepting unit 300, the confidential job determining unit 301, the decomposing processing unit 302, the sheet transport mechanism control unit 303, the sheet determination unit 304, the retract mechanism control unit 305, and the like by operating according to the program 310. Details of each means 300 to 305 will be described later. The confidential job determination unit 301 is an example of a determination unit. The decompression processing unit 302 is an example of a conversion unit. The retract mechanism control unit 305 is an example of a moving unit.

  The storage unit 31 includes a ROM (Read Only Memory), a RAM (Random Access Memory), a hard disk, and the like, and stores various information such as a program 310 and confidential document storage location information 311. The confidential document storage location information 311 is storage location information indicating the storage location of the confidential document, such as a folder path of the document server 21.

  Next, each means 300-305 of the control part 30 is demonstrated.

  The accepting unit 300 accepts a copy job based on an operation on the operation display unit 7. In the copy job, scan data is received from the image reading unit 8. The accepting unit 300 accepts PDL (page description language) data and storage location information along with the print job from the printer driver of the terminal device 20. Hereinafter, the scan data and the PDL data are also referred to as print data.

  The confidential job determination unit 301 determines whether the print job received by the reception unit 300 is a confidential job (hereinafter also referred to as “confidential job”). If the print job received by the receiving unit 300 is a copy job, the confidential job determination unit 301 determines that the copy job is a confidential job. Further, when the print job accepted by the accepting unit 300 is a print job, the confidential job determining unit 301 determines based on the storage destination information of the document data designated by the printer driver. That is, if the storage destination information is registered in the confidential document storage destination information 311, it is determined that the print job is a confidential job, and if it is not registered, it is determined that the print job is a normal print job. For example, the confidential job determination unit 301 performs the above determination before the paper P is fed from the paper feed tray 5.

  When the confidential job determining unit 301 determines that the job is a confidential job, the decomposing processing unit 302 performs a decomposing process that does not use K. The decomposing process refers to a process for converting PDL data or scan data into bitmap format image data for each CMYK. In this embodiment, since the decomposing process does not use K, PDL data or scan data for color image or monochrome image is converted into CMY image data, and K image data is not generated.

  The decomposing processing unit 302 performs normal decomposing processing when the confidential job determining unit 301 determines that the job is not a confidential job. That is, PDL data or scan data for a color image is converted into CMYK image data, and PDL data or scan data for a monochrome image is converted into K image data.

  The paper transport mechanism control unit 303 controls the paper transport mechanism 17 according to the print mode designated by the user. Further, the paper transport mechanism control unit 303 controls the paper transport mechanism 17 to feed the paper P from the paper feed tray 5A before the primary transfer.

  The paper determination unit 304 feeds the paper P from the paper feed tray 4A, and when the detection signal is transmitted from the security paper detection unit 13 at the timing when the paper P passes through the security paper detection unit 13, the paper is fed. When it is determined that the paper P is a security paper and no detection signal is transmitted within a predetermined time including the timing when the paper P passes the security paper detection unit 13, the fed paper P is normal. Judged to be paper.

  The retract mechanism control means 305 controls the retract mechanism 18 when the confidential job determination means 301 determines that the print job is a confidential job and the paper determination means 304 determines that the paper P is plain paper. Thus, the CMY photosensitive drums 161C, 161M, and 161Y are positioned so as not to contact the intermediate transfer belt 173 due to relative movement with respect to the intermediate transfer belt 173. The retract mechanism 18 of this embodiment is normally in a position where the CMY photosensitive drums 161C, 161M, and 161Y are in contact with the intermediate transfer belt 173. Accordingly, when the print job is a confidential job and the paper P is plain paper, the retract mechanism control unit 305 controls the retract mechanism 18 to change the CMY photosensitive drum units 164C, 164M, and 164Y to CMY. The photosensitive drums 161 </ b> C, 161 </ b> M, and 161 </ b> Y are moved to positions where they do not contact the intermediate transfer belt 173.

(Operation of the first embodiment)
Next, an example of the operation of the image forming apparatus 1 will be described with reference to FIGS. FIG. 4 is a chart for explaining an example of the operation of the image forming apparatus 1. FIG. 5 is a flowchart illustrating an example of the operation of the image forming apparatus 1.

  When the reception unit 300 receives a print job (S1), the confidential job determination unit 301 determines whether the print job received by the reception unit 300 is a confidential job (S2). If the print job is a copy job that scans and copies a document, it is determined to be a confidential job. When the storage device information of PDL data and document data is transmitted together with the print job from the terminal device 20 via the communication unit 9, the storage destination information of the document data is stored in the confidential document storage location information 311 stored in the storage unit 31. If registered, it is determined that the job is a confidential job.

  When it is determined that the job is a confidential job (S2: Yes), the decomposing process unit 302 performs a decomposing process that does not use K (S3).

  The paper transport mechanism control unit 303 controls the paper transport mechanism 17 to feed paper. The paper P is taken out from the paper feed tray 4A and fed to the paper transport path 6 (S4).

  The paper determination unit 304 determines whether or not the paper P is a security paper based on the presence or absence of a detection signal from the security paper detection unit 13 (S5).

  If it is determined that the sheet is a security sheet (S5: Yes), the control unit 30 controls the image forming unit 16 to perform a printing process using CMY (S6).

  The security paper printed with a color image or black and white image made up of CMY is discharged to the paper discharge tray 5 (S7).

  If it is determined in step S5 that the paper is plain paper (S5: No), the retract mechanism control unit 305 controls the retract mechanism 18 to transfer the CMY photosensitive drum units 164C, 164M, and 164Y to the intermediate transfer belt 173. (S8).

  The K photoconductive drum 161K is in contact with the intermediate transfer belt 173, but no toner image is formed on the K photoconductive drum 161K. Therefore, even if the K photoconductor drum 161K is secondarily transferred from the intermediate transfer belt 173 to the paper P. The plain paper is discharged to the paper discharge tray 5 while remaining blank (S10).

  If it is determined in step S2 that the job is not a confidential job (S2: No), the decomposing processor 302 performs a normal decomposing process (S11).

  The paper transport mechanism control unit 303 controls the paper transport mechanism 17 to feed paper. The paper P is taken out from the paper feed tray 4A and fed to the paper transport path 6 (S12).

  The control unit 30 controls the image forming unit 16 to perform a printing process using CMYK (S13).

  The plain paper printed with a color image or black and white image made up of CMYK is discharged to the paper discharge tray 5 (S14).

[Second Embodiment]
FIG. 6 is a flowchart showing an example of the operation of the image forming apparatus according to the second embodiment of the present invention. In the first embodiment, the CMY photosensitive drums 161C, 161M, and 161Y are in a normal state where they contact the intermediate transfer belt 173. However, in this embodiment, the CMY photosensitive drums 161C, 161M, and 161Y are in contact with each other. The position that does not contact the intermediate transfer belt 173 (retract position) is the normal state, and the rest is configured in the same manner as in the first embodiment. The following description will focus on differences from the first embodiment.

  When the CMY toner image is transferred to the intermediate transfer belt 173, the retract mechanism 18 according to the present embodiment controls the CMY photosensitive drums 161C, 161M, and 161Y to the intermediate transfer belt 173 under the control of the retract mechanism control unit 305. Make contact.

  First, as an initial state, the retract mechanism control unit 305 controls the retract mechanism 18 to move the CMY photosensitive drums 161C, 161M, 161Y away from the intermediate transfer belt 173 (S21).

  When the accepting unit 300 accepts a print job as in the first embodiment (S22), the confidential job determination unit 301 receives the print job accepted by the accepting unit 300 as in the first embodiment. It is determined whether the job is a confidential job (S23).

  If it is determined that the job is a confidential job (S23: Yes), the decomposing process unit 302 performs a decomposing process without using K (S24).

  The paper transport mechanism control unit 303 controls the paper transport mechanism 17 to feed paper. The paper P is taken out from the paper feed tray 4A and fed to the paper transport path 6 (S25).

  The paper determination unit 304 determines whether or not the paper P is a security paper based on the presence or absence of a detection signal from the security paper detection unit 13 (S26).

  When the security sheet is detected (S26: Yes), the retract mechanism control unit 305 controls the retract mechanism 18 to bring the CMY photosensitive drums 161C, 161M, 161Y into contact with the intermediate transfer belt 173 (S26). S27).

  The control unit 30 controls the image forming unit 16 to perform a printing process using CMY (S28).

  The security paper printed with a color image or black and white image made up of CMY is discharged to the paper discharge tray 5 (S29).

  If it is determined in step S26 that the paper is plain paper (S26: No), the retract mechanism control unit 305 maintains a position where the CMY photosensitive drums 161C, 161M, 161Y do not contact the intermediate transfer belt 173. .

  The K photoconductive drum 161K is in contact with the intermediate transfer belt 173, but no toner image is formed on the K photoconductive drum 161K. Therefore, even if the K photoconductor drum 161K is secondarily transferred from the intermediate transfer belt 173 to the paper P. The plain paper is discharged to the paper discharge tray 5 while remaining blank (S31).

  If it is determined in step S23 that the job is not a confidential job (S23: No), the decomposing processor 302 performs a normal decomposing process (S32).

  The paper transport mechanism control unit 303 controls the paper transport mechanism 17 to feed paper. The paper P is taken out from the paper feed tray 4A and fed to the paper transport path 6 (S33).

  The control unit 30 controls the image forming unit 16 to perform a printing process using CMYK (S34).

  The plain paper printed with a color image or black and white image composed of CMYK is discharged to the discharge tray 5 (S35).

[Third Embodiment]
In the third embodiment of the present invention, the image forming apparatus 1 according to the first or second embodiment is placed in a specific area (including a room) in which a gate for detecting security paper is provided at the entrance / exit. It is installed.

  The gate includes a security paper detection unit having the same function as the security paper detection unit 13, and a communication unit that communicates a detection result with an external device when the security paper detection unit detects a security paper.

  It is possible to detect that a confidential document is printed on a security sheet and it is taken out of a specific area through a gate. At this time, a warning may be notified from the gate to the terminal device of the administrator. The installation location of the image forming apparatus 1 is not limited to the area.

(Modification 1)
FIGS. 7A and 7B are diagrams for explaining another configuration of the retract mechanism as the first modified example, in which FIG. 7A is a schematic diagram of a main part before and after the retract.

  In each of the embodiments described above, the retract mechanism 18 moves the CMY photosensitive drum units 164C, 164M, and 164Y to bring the CMY photosensitive drums 161C, 161M, and 161Y into contact with the intermediate transfer belt 173. The primary transfer roll 162 is moved to bring the intermediate transfer belt 173 into contact with the CMY photosensitive drums 161C, 161M, 161Y. Also in this case, the K photosensitive drum 161K is always kept in contact with the intermediate transfer belt 173. According to the first modification, the primary transfer roll 162 of the movable part is smaller and lighter than the photosensitive drum units 164C, 164M, and 164Y. Therefore, the retract mechanism can be reduced in size and weight.

(Modification 2)
In each of the above embodiments, the security paper is fed from the paper feed tray 4A and the security paper detection unit 13 is provided on the paper ejection side of the paper feed tray 4A. However, the security paper detection unit is provided on the paper ejection side of the manual feed tray 4B. 13 may be provided to feed security paper from the manual feed tray 4B.

(Modification 3)
In each of the above embodiments, the security paper has been described as the predetermined paper. However, the predetermined paper is a plain paper (back paper) on which one side is printed, or both sides are not printed. It may be plain paper. In this case, if one side of the backing paper is fed as the printing target side, or if paper with both sides printed is fed, a paper other than the predetermined paper Therefore, it is possible to discharge a blank sheet without printing, and avoid unnecessary printing.

(Modification 4)
In step S5 in the flowchart shown in FIG. 5 and in step S26 in the flowchart shown in FIG. 6, when it is determined that the sheet is not security paper, it is not security paper when it is determined or when blank plain paper is discharged. A warning to that effect may be displayed on the operation display unit 7. Note that the warning may be sound only, or a sound may be generated together with the warning display.

(Modification 5)
In step S13 of the flowchart shown in FIG. 5 and step S34 of the flowchart shown in FIG. 6, the CMY photosensitive drums 161C, 161M, and 161Y are not moved to positions that do not contact the intermediate transfer belt 173 (retract positions). If the print data is for monochrome images, the print data may be moved to the retract position. In this case, the conveyance resistance of the intermediate transfer belt 173 is suppressed, and the conveyance speed can be increased.

  Although the embodiments of the present invention have been described above, the embodiments of the present invention are not limited to the above-described embodiments, and various modifications and implementations are possible without departing from the scope of the present invention. is there.

  Each part of the control unit 30 may be partially or entirely configured by a hardware circuit such as a reconfigurable circuit (FPGA: Field Programmable Gate Array) or an application specific integrated circuit (ASIC). Good.

  Further, it is possible to omit or change some of the constituent elements of the above-described embodiment within a range not changing the gist of the present invention. In addition, steps can be added, deleted, changed, replaced, and the like in the flow of the above-described embodiment without departing from the scope of the present invention. The program used in the above embodiment can be provided by being recorded on a computer-readable recording medium such as a CD-ROM. The program used in the above embodiment can be stored in an external server such as a cloud server and used via a network.

DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus, 2 ... Housing | casing, 3 ... Controller, 4A ... Paper feed tray, 4B ... Manual feed tray, 5, 5A-5C ... Paper discharge tray, 6 ... Paper conveyance path, 7 ... Operation display part, 8 ... Image reading unit, 9 ... communication unit, 11 ... pickup roll, 12 ... conveyance roll, 13 ... security paper detection unit, 14 ... secondary transfer roll, 15 ... fixer, 16 ... image forming unit, 17 ... paper conveyance mechanism, 17 ... Reversing unit, 18 ... Retract mechanism, 19 ... Network, 20 ... Terminal device, 21 ... Document server, 30 ... Control unit, 31 ... Storage unit, 60 ... Take away path, 61 ... Manual feed path, 62 ... Registration path 63, 63a-63c ... paper discharge pass, 64 ... duplex printing pass, 160, 160C, 160M, 160Y, 160K ... image forming unit, 161, 161C, 161M, 161Y, 161 ... Photoconductor drums 162, 162C, 162M, 162Y, 162K ... Primary transfer rolls, 163, 163C, 163M, 163Y, 163K ... Developers, 164C, 164M, 164Y, 164K ... Photoconductor drum units, 170 ... Drive rolls, 171 ... backup roll, 172 ... driven roll, 173 ... intermediate transfer belt, 300 ... acceptance means, 301 ... confidential job determination means, 302 ... decompose processing means, 303 ... paper transport mechanism control means, 304 ... paper determination means, 305 ... retract Mechanism control means, 310 ... program, 311 ... confidential document storage location information, P ... paper

Claims (12)

A plurality of image holding members respectively holding toner images corresponding to a plurality of color components;
An intermediate transfer member for holding toner images sequentially stacked as primary transfer from the plurality of image carriers;
Secondary transfer means for secondary transfer of the toner image on the intermediate transfer member to a sheet;
Converting means for converting the print data into image data for each predetermined color component excluding black among the plurality of color components when print data is received as a print target on a predetermined paper;
When the sheet fed from the sheet feeding unit is a sheet other than the predetermined sheet, the image carrier corresponding to the predetermined color component is moved relative to the intermediate transfer body by the relative movement. Moving means for making the position not in contact with the intermediate transfer member;
An image forming apparatus. The image carrier corresponding to the predetermined color component is in a normal position at a position in contact with the intermediate transfer member,
The moving means contacts the intermediate transfer member with an image carrier corresponding to the predetermined color component when the paper fed from the paper feeding unit is a paper other than the predetermined paper. Move it to a relative position,
The image forming apparatus according to claim 1. The image carrier corresponding to the predetermined color component is a normal position where it does not contact the intermediate transfer member,
When the sheet fed from the sheet feeding unit is the predetermined sheet, the moving unit moves the image holding body corresponding to the predetermined color component to a position in contact with the intermediate transfer body. Move relative,
The image forming apparatus according to claim 1. A determination means for determining whether or not the print data is to be printed on a predetermined paper;
The image forming apparatus according to claim 1. An operation unit for receiving a user operation is further provided,
The determination unit determines that the print data is a target to be printed on a predetermined sheet when a print instruction for the print data is received by operating the operation unit.
The image forming apparatus according to claim 4. The determination unit determines whether the print data is a target to be printed on a predetermined paper based on information included in the print instruction when a print instruction for the print data is received from an external device;
The image forming apparatus according to claim 4. The print instruction includes storage location information indicating a storage location of the print data,
The determination unit determines that the print data is a target to be printed on a predetermined sheet when the storage destination information is included in the storage destination information stored in advance.
The image forming apparatus according to claim 6. The determination unit determines whether or not the print data is to be printed on a predetermined sheet before the sheet is fed from the sheet feeding unit.
The image forming apparatus according to claim 4. The paper feeding unit feeds paper before the primary transfer;
The image forming apparatus according to claim 1. The print data is confidential information,
The predetermined paper is a paper provided with a magnetic material.
The image forming apparatus according to claim 1. The predetermined paper is a paper on which one side is printed, or a paper on which both sides are not printed,
The paper other than the predetermined paper is a paper on which the other surface of the paper on which the one surface is printed is fed as a printing target surface, or a paper on which both surfaces are printed.
The image forming apparatus according to claim 1. A plurality of image holders respectively holding toner images corresponding to a plurality of color components; an intermediate transfer body holding toner images sequentially stacked as primary transfer from the plurality of image holders; A secondary transfer unit that secondary-transfers the toner image onto a sheet;
Conversion means for converting the print data into image data for each color component other than black among the plurality of color components when print data is received as a print target on a predetermined paper;
When the sheet fed from the sheet feeding unit is a sheet other than the predetermined sheet, the image carrier corresponding to the predetermined color component is moved relative to the intermediate transfer body by the relative movement. Moving means for making the position not in contact with the intermediate transfer member;
Program to function as.

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