JP2011154299A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent deviation of a replacement time. <P>SOLUTION: The image forming apparatus includes: image carriers according to toner colors, each composed of a cylindrical member, carrying a toner image on the circumferential surface thereof, and coming into contact with a transfer body so as to transfer the toner image to the transfer body; and a developing part configured to supply the toner to the image carrier; wherein a contact/non-contact state between the image carrier and the transfer body is switched according to a printing condition in the printing period. The image forming apparatus includes a recording means configured to, in the case the image carrier and the transfer body come into contact with each other and also the developing part operates in the printing period, record that the image carrier and the developing part are operated and consumed. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an image forming apparatus.

  An electrophotographic image forming apparatus brings all photosensitive drums of Y (yellow), M (magenta), C (cyan), and K (black) into contact with a transfer body (such as an intermediate transfer belt) during full-color image formation. By operating all these photosensitive drums and their developing devices, a full color image is generated on the transfer body. In addition, the image forming apparatus is configured such that when a monochrome image is formed, the Y, M, and C photosensitive drums other than K are not brought into contact with the transfer body, and the K photosensitive drum and the developing device are operated to perform the transfer. Generate a monochrome image on the body. However, when monochrome printing and full-color printing are mixed, if priority is given to printing speed, monochrome printing is performed with the Y, M, and C photosensitive drums in contact with the transfer body. In monochrome printing in this case, an image is formed only on the K photosensitive drum, and the Y, M, and C photosensitive drums only rotate in accordance with the movement of the transfer body. For example, the following Patent Document 1 discloses an image forming apparatus as described above.

JP 2000-39816 A

  By the way, in the above prior art, when monochrome printing and full-color printing are mixed, in order to give priority to the printing speed, monochrome copying is executed with the Y, M, and C photosensitive drums in contact with the transfer body. . However, at this time, the Y, M, and C photosensitive drums also rotate and come into contact with the transfer body, that is, these photosensitive drums are consumed, but the K photosensitive drum is recorded as consumed. , C is not recorded as exhausted. The developing unit operates in the same manner as the photosensitive drum, but is not recorded as exhausted. For this reason, there is a discrepancy between the actual consumption level of the photosensitive drum and the developing unit and the consumption level on recording, so that there is a deviation in the replacement timing of the photosensitive drum.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to prevent the replacement time from being shifted.

  In order to achieve the above object, according to the present invention, as a first solving means related to an image forming apparatus, a toner image is formed on a peripheral surface of a cylindrical member, and the toner image is transferred to the transfer member by contacting the peripheral surface. The image bearing member according to the color of the toner is transferred, and a developing unit that supplies the toner to the image bearing member, and contact between the image bearing member and the transfer member according to printing conditions during printing. An image forming apparatus that switches between non-contact, and when the image carrier and the transfer member are in contact with each other during printing and the developing unit is moving, the image carrier and the developing unit are consumed. A means of providing a recording means for recording is adopted.

  According to the present invention, as a second solving means relating to the image forming apparatus, in the first solving means described above, an image forming apparatus in which only one color image carrier is brought into contact with a transfer body during monochrome printing, wherein the recording means In the case of monochrome printing, if the image carrier and the transfer member are in contact with each other and the developing unit is moving, means for recording that the image carrier and the developing unit are consumed. adopt.

  According to the present invention, when the image carrier and the transfer member are in contact with each other during printing and the developing unit is moving, the image carrier is recorded as consumed, that is, the image carrier is in contact as in the conventional case. As a result, the replacement time of the image carrier can be prevented from being deviated as compared with the case where it is not recorded as consumed when it is not used for printing. Further, according to the present invention, when the developing unit is moving, the developing unit is recorded as consumed, so that it is possible to prevent the development unit from being replaced at a different timing.

FIG. 3 is a functional block diagram of a multifunction peripheral A according to an embodiment of the present invention. 1 is a cross-sectional view illustrating a schematic configuration of a multifunction peripheral A according to an embodiment of the present invention. It is a schematic diagram which shows operation | movement of the movement unit 431 of the multifunctional machine A which concerns on embodiment of this invention.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
First, the configuration of the multifunction peripheral A according to the present embodiment will be described with reference to FIGS. 1 and 2.
The multifunction peripheral A (image forming apparatus) according to the present embodiment has a copy function, a print function, a scan function, a facsimile transmission / reception function, and an e-mail transmission function. As shown in FIG. 1, the multi-function device A includes an image reading unit 1, an image data storage unit 2, an image processing unit 3, a paper transport / image forming unit 4, an operation display unit 5, a communication I / F unit 6, and The main controller 7 is used. The sheet conveyance / image forming unit 4 and the main controller 7 constitute a recording unit in the present embodiment.

  The image reading unit 1 includes an ADF (automatic document feeder) 1a and a CCD (Charge Coupled Device) sensor 1b. The image of the document sequentially fed by the ADF 1a is read by the CCD sensor under the control of the main controller 7. The document image data based on the document image is output to the main controller 7. On the other hand, the main controller 7 stores the document image data in the image data storage unit 2. As shown in FIG. 2, the image reading unit 1 constitutes the upper part of the multifunction peripheral A. Specifically, the ADF 1a includes a document tray, a pickup roller, a transport roller, a paper discharge roller, and a document discharge tray. A plurality of documents set on the document tray are taken into the inside one by a pickup roller, and the document is transported. When the original is read by the CCD sensor on the original table, the original is discharged to the original discharge tray by the discharge roller.

  The image data storage unit 2 is, for example, a flash memory or a hard disk. Document image data, print image data received from the outside (client computer, public network, etc.) by the communication I / F unit 6 under the control of the main controller 7 and Facsimile image data is stored. The image data storage unit 2 stores document image data, print image data, and facsimile image data as bitmap data.

  The image processing unit 3 performs various types of image processing (for example, image processing corresponding to enlargement / reduction copying) on the image data input from the image data storage unit 2 under the control of the main controller 7, and converts the image data into the image data. The image data is converted into image data in an image forming format and output to the paper transport / image forming unit 4. When the image reading unit 1 reads a color original, the image data input from the image data storage unit 2 to the image processing unit 3 is RGB image data (color image data) corresponding to the three primary colors of light. Reference numeral 3 denotes image data corresponding to the image forming format using such RGB image data, for example, YMCK image data, that is, an image having Y (yellow), M (magenta), C (cyan), and K (black) as reference colors. The data is converted and output to the paper transport / image forming unit 4.

  The paper transport / image forming unit 4 forms an image on the printing paper by transferring the toner to the printing paper based on the printing format image data input from the image processing unit 3 and performing the fixing process of the toner. Is. The sheet transport / image forming unit 4 includes a sheet transport / image forming CPU (Central Processing Unit) 4a, a sheet transport / image forming ROM (Read Only Memory) 4b, and a sheet transport / image forming RAM (shown in FIG. 1). Random Access Memory) 4c, image forming units 41K, 41Y, 41C, 41M for forming images (toner images) corresponding to the respective colors (K, Y, C, M) shown in FIG. 2, laser scanning unit 42, transfer unit 43, a fixing unit 44, toner cartridges 45K, 45Y, 45C, and 45M, a paper feed roller 46, a paper cassette 47, and a paper feed tray 48.

The sheet transport / image forming CPU 4a controls the overall operation of the sheet transport / image forming unit 4 based on a control command from the main controller 7 and a control program stored in the sheet transport / image forming ROM 4b.
The sheet transport / image forming ROM 4b is a non-volatile memory that stores a control program executed by the sheet transport / image forming CPU 4a and other data.
The paper transport / image forming RAM 4c is a volatile memory used as a working area that is a temporary storage destination of data when the paper transport / image forming CPU 4a executes a control program and performs various operations.

  The image forming units 41K, 41Y, 41C, and 41M are arranged at predetermined intervals in the horizontal direction in order from the left side when viewed from the front of the multifunction peripheral A, and are respectively photosensitive drums (41aK, 41aY, 41aC, and 41aM) (image carriers). Body), charging unit (41bK, 41bY, 41bC, 41bM), developing unit (41cK, 41cY, 41cC, 41cM), static eliminating unit (41dK, 41dY, 41dC, 41dM), cleaner (41eK, 41eY, 41eC, 41eM) I have. As described above, since the image forming units 41K, 41Y, 41C, and 41M have the same configuration, the following description focuses on the image forming unit 41K.

  The photosensitive drum 41aK is a cylindrical member in which an electrostatic latent image and a toner image based on the electrostatic latent image are formed on the circumferential surface thereof, and is arranged extending in the depth direction when viewed from the front of the multifunction device A. The image forming apparatus rotates in the circumferential direction (the direction of the arrow of the photosensitive drum 41aK in FIG. 2) during image formation by a driving unit (not shown) capable of speed adjustment provided independently for each. The charging unit 41bK is disposed to face the photosensitive drum 41aK and makes the peripheral surface of the photosensitive drum 41aK charged. The developing unit 41cK supplies toner (here, black toner) to the peripheral surface of the photosensitive drum 41aK, thereby causing a toner image (here, black toner image) based on the electrostatic latent image on the peripheral surface of the photosensitive drum 41aK. ) Is formed (developed).

The neutralization unit 41dK irradiates the photosensitive drum 41aK with a neutralizing light in preparation for the next round of image formation, thereby neutralizing the surface of the photosensitive drum 41aK to make it electrically neutral. The cleaner 41eK removes the toner remaining on the photosensitive drum 41aK after the toner image is transferred from the photosensitive drum 41aK to a transfer unit 43 (to be described in detail below).
The laser scanning unit 42 is disposed below each of the image forming units 41K, 41Y, 41C, and 41M, and scans each color by scanning the laser light on the peripheral surfaces of the charged photosensitive drums 41aK, 41aY, 41aC, and 41aM. An electrostatic latent image corresponding to the above is formed.

  The intermediate transfer unit 43 is disposed above each of the image forming units 41K, 41Y, 41C, and 41M, and rotates the intermediate transfer belt 43a for primary transfer and the intermediate transfer belt 43a in the direction of the dotted arrow in FIG. Drive roller 43b, tension roller 43c for applying tension to the intermediate transfer belt 43a, driven roller 43d that rotates in accordance with the rotation of the intermediate transfer belt 43a, and passing a transfer current to the intermediate transfer belt 43a to cause each photosensitive drum 41aK. , 41aY, 41aC, 41aM primary transfer rollers 43eK, 43eY, 43eC, 43eM for transferring the toner images to the intermediate transfer belt 43a, and secondary transfer for secondary transfer of the toner images on the intermediate transfer belt 43a to the printing paper. A roller 43f and a density sensor (ID sensor) 43g are provided.

  The driven roller 43d and the primary transfer rollers 43eY, 43eC, 43eM are unitized as an integral moving unit 431. The moving unit 431 has a driving device (not shown), and is positioned at the upper position shown in FIG. 3A or the lower position shown in FIG. 3B by the driving device under the control of the CPU 4a for sheet conveyance / image formation. Is switched to contact / non-contact between the 41aY, 41aC, 41aM and the intermediate transfer belt 43a.

  The moving unit 431 is positioned at the upper position shown in FIG. 3A during monochrome printing. When the moving unit 431 is located at the upper position as shown in FIG. 3A, the intermediate transfer belt 43a is pulled upward, so that the photosensitive drums 41aY, 41aC, and 41aM and the intermediate transfer belt 43a are transferred as shown in FIG. The belt 43a is separated. Only the photosensitive drum 41aK operates to execute monochrome printing.

  Further, the moving unit 431 is positioned at the lower position shown in FIG. 3B during full color printing or monochrome printing with priority on printing speed. When the moving unit 431 is positioned at the lower position as shown in FIG. 3B, the intermediate transfer belt 43a is pulled downward, so that the photosensitive drums 41aY, 41aC, 41aM and the intermediate transfer belt are shown in FIG. 3B. 43a is separated. Then, full-color printing is executed by operating the photosensitive drums 41aK, 41aY, 41aC, and 41aM. When priority is given to the printing speed, monochrome printing using only the photosensitive drum 41aK is performed in the state shown in FIG. That is, monochrome printing is executed while the position of the moving unit 431 is kept at the lower position. As a result, there is no loss of time for switching the moving unit 431, and the printing speed can be increased accordingly. At this time, the photosensitive drums 41aY, 41aC, and 41aM are not formed with toner images on their surfaces, but are rotated in accordance with the movement of the intermediate transfer belt 43a.

  The ID sensor 43g detects the toner density on the transfer surface of the intermediate transfer belt 43a, and is attached between the secondary transfer roller 43f and the photosensitive drum 41aK and on both the left and right sides in the traveling direction of the intermediate transfer belt 43a. . The ID sensor 43g irradiates the transfer surface of the intermediate transfer belt 43a with light, detects the toner density of the intermediate transfer belt from the difference in the reflected light quantity and the diffused light quantity of the light, and a detection signal (voltage signal) indicating the toner density. ) Is output to the CPU 4a for paper conveyance / image formation. In the ID sensor 43g, the lower the toner density of the intermediate transfer belt 43a, the higher the voltage of the detection signal.

  In such an intermediate transfer unit 43, the toner images of the respective colors developed on the respective photosensitive drums 41aK, 41aY, 41aC, and 41aM are once superimposed on the intermediate transfer belt 43a, and then the driving roller 43b and the secondary transfer roller. 43f is transferred all at once to the printing paper transported between 43f.

The fixing unit 44 fixes the toner image transferred on the printing paper by the intermediate transfer unit 43 to the printing paper by applying heat and pressure, and is arranged in the printing paper conveyance path.
The toner cartridges 45 </ b> K, 45 </ b> Y, 45 </ b> C, and 45 </ b> M store toner of each color to be supplied to the developing units 41 cK, 41 cY, 41 cC, and 41 cM, and are disposed above the intermediate transfer unit 43. Further, a paper feed roller 46 is provided at the lower part of the apparatus. The paper feed roller 46 allows printing paper to be transferred from the paper cassette 47 or the paper feed tray 48 to the above-described intermediate transfer unit 43 (specifically, the drive roller 43b). And the secondary transfer roller 43f).

  Returning to FIG. 1, the operation display unit 5 includes hardware keys such as a copy function key, a print function key, a scan function key, a facsimile function key, a start key, a stop / clear key, a power key, and a numeric keypad (numeric input key). , A touch panel is provided, and each key operation instruction is output to the main controller 7 and various screens are displayed on the touch panel under the control of the main controller 7. The copy function key, print function key, scan function key, and facsimile function key are keys for activating each function.

  The communication I / F unit 6 is connected to an external client computer and a public network, and transmits / receives various signals to / from the client computer and the public network. The communication I / F unit 6 outputs print image data input from the client computer and facsimile image data input from the public network to the main controller 7. On the other hand, the CPU 1 stores print image data and facsimile image data in the image data storage unit 2.

The main controller 7 controls the overall operation of the multifunction peripheral A, and includes a CPU 7a, a ROM 7b, and a RAM 7c as shown in FIG.
The CPU 7a includes a control program stored in the ROM 7b, document image data, print image data and facsimile image data stored in the image data storage unit 2, operation instructions input from the operation display unit 5, and a communication I / F unit. 6 controls the overall operation of the multifunction peripheral A based on various instructions input from the outside (client computer, public network, etc.) 6.
The ROM 7b is a non-volatile memory that stores a control program executed by the CPU 7a and other data.
The RAM 7c is a volatile memory used as a working area serving as a temporary storage destination of data when the CPU 7a executes a control program and performs various operations.

Next, the operation of the MFP A according to the present embodiment having the above configuration will be described with reference to FIG.
As described above, in the MFP A, the moving unit 431 is located at the upper position as shown in FIG. 3A during monochrome printing. Further, the moving unit 431 is positioned at a lower position as shown in FIG. 3B during full-color printing or monochrome printing with priority on printing speed.
At this time, the CPU 4a for paper conveyance / image formation notifies the CPU 7a of the main controller 7 of the photosensitive drums 41aK, 41aY, 41aC, 41aM to be operated and the developing units 41cK, 41cY, 41cC, 41cM. That is, in monochrome printing with the moving unit 431 positioned at the upper position shown in FIG. 3A, the CPU 7a is notified that the photosensitive drum 41aK and the developing unit 41cK are operating. Further, in full color printing with the moving unit 431 positioned at the lower position as shown in FIG. 3B or monochrome printing with priority on printing speed, the photosensitive drums 41aK, 41aY, 41aC, 41aM and the developing units 41cK, The CPU 7a is notified that 41cY, 41cC, and 41cM are operating.

 Then, the sheet conveying / image forming CPU 4a expresses information notified to the CPU 7a by 4-bit information. That is, one bit of 4-bit information is assigned to each photosensitive drum and developing unit combination of K (black), Y (yellow), M (magenta), and C (cyan). When the developing unit is operating, 1 is set to the corresponding bit, and when the photosensitive drum and the developing unit are not operating, 0 is set to the corresponding bit. Specifically, the 4-bit information at the time of monochrome printing is “1000”, and is “1111” at the time of full-color printing or monochrome printing with priority on the printing speed.

Then, the CPU 7a records the degree of wear for each combination of the photosensitive drum and the developing unit for each of K, Y, M, and C based on the 4-bit information notified from the paper transport / image forming CPU 4a. That is, when the combination of the photosensitive drum and the developing unit is operating, the CPU 7a records that it is consumed.
As described above, in the MFP A according to the present embodiment, when the photosensitive drum and the transfer body are in contact with each other and the developing unit is moving, the photosensitive drum and the developing unit are recorded as consumed. That is, even during monochrome printing with priority on printing speed, recording is performed assuming that the Y, M, and C photosensitive drums and the developing unit are consumed, so that the replacement timing of the photosensitive drum and the developing unit can be prevented from deviating from the conventional one.

As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said embodiment, For example, the following modifications can be considered.
(1) In the above embodiment, the monochrome printing described above is printing using K (black), but printing using any of Y (yellow), M (magenta), and C (cyan). Also good. In this case, the sheet transport / image forming CPU 4a notifies the CPU 7a that any combination of the photosensitive drums Y, M, and C and the developing unit has been operated.

A ... MFP, 1 ... image reading unit, 1a ... ADF, 1b ... CCD sensor, 2 ... image data storage unit, 3 ... image processing unit, 4 ... paper transport / image forming unit (recording means), 5 ... operation display , 6 ... Communication I / F part, 7 ... Main controller (recording means), 4a ... Paper transport / image forming CPU, 4b ... Paper transport / image forming ROM, 4c ... Paper transport / image forming RAM, 41K , 41Y, 41C, 41M ... image forming unit, 42 ... laser scanning unit, 43 ... transfer unit, 44 ... fixing unit, 45K, 45Y, 45C, 45M ... toner cartridge, 46 ... paper feed roller, 47 ... paper cassette, 48 Paper feed tray, 41aK, 41aY, 41aC, 41aM ... Photosensitive drum (image carrier), 41bK, 41bY, 41bC, 41bM ... Charging unit, 41cK, 4 cY, 41cC, 41cM ... developing part, 41dK, 41dY, 41dC, 41dM ... neutralization part, 41eK, 41eY, 41eC, 41eM ... cleaner, 43a ... intermediate transfer belt, 43b ... drive roller, 43c ... tension roller, 43d ... driven roller 43eK, 43eY, 43eC, 43eM ... primary transfer roller, 43f ... secondary transfer roller, 43g ... ID sensor, 7a ... CPU, 7b ... ROM, 7c ... RAM

Claims (2)

Consists of a cylindrical member. A toner image is carried on the circumferential surface, and the toner image is transferred to the transfer body by contact, and an image carrier corresponding to the color of the toner, and the toner is supplied to the image carrier. An image forming apparatus that switches between contact / non-contact between the image carrier and the transfer body according to printing conditions during printing,
And recording means for recording that the image carrier and the developing unit are consumed when the image carrier and the transfer member are in contact with each other and the developing unit is moving during printing. Image forming apparatus. An image forming apparatus in which only a single color image carrier is brought into contact with a transfer body during monochrome printing,
The recording unit records that the image carrier and the developing unit are consumed when the image carrier and the transfer member are in contact with each other and the developing unit is moving even during monochrome printing. The image forming apparatus according to claim 1.

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