JP2018180080A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus that, when a defect occurs in an image consisting of toner images, enables a person instructing a checking operation to check whether the cause of the defect is in processes after a transfer part.SOLUTION: An image forming apparatus comprises: an image forming part that forms toner images; a transfer part that transfers the toner images formed by the image forming part to a recording medium 9; and control means that controls the image forming part to form toner images having two or more types of parallel line tint patterns P1, P2 with different angles as images for checking Ga, Gb before controlling the transfer part to execute an operation to transfer the images for checking to the recording medium 9.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an image forming apparatus.

  Conventionally, as an image forming apparatus having a function of estimating the cause of generation of an abnormal image, for example, those described in the following patent documents are known.

First, in Patent Document 1, a sample image is output as an image which is not output in normal image processing, and the sample image is read by an image input device to determine whether an abnormal image is generated or not. There has been disclosed an image forming apparatus which finds out a sign that an abnormal image will occur before an abnormality occurs, and makes an early treatment response. Further, it is shown in Patent Document 1 that the fixing roller and the pressure roller of the fixing device are deformed as the abnormality, and that there is much moisture on the photosensitive drum.
Further, according to Patent Document 2, an amount of deviation of image data with respect to a normal state is calculated, and state determination means for determining whether or not it is an abnormal state based on the amount of deviation; When it is determined that the image processing means performs image processing for abnormality according to the output of the abnormal point specifying means when the part specifying means and the state determining means determine that the state is abnormal An image forming apparatus is disclosed which comprises: a serviceman call output unit that outputs a serviceman call signal.

Further, in Patent Document 3, an image input means, an image forming means for forming an output image on a recording medium based on the input image data, a discharge means for discharging the recording medium on which the image is recorded, and discharging Image reading means for outputting a read image obtained by reading the recorded recording medium, and an abnormality detection image generating means for outputting image data for abnormality detection which is likely to generate an abnormal image due to the charging unit of the image forming means; It has comparison means for comparing the output data from the image reading means which has read the recording medium on which the output image is formed based on the detection image data, and the inputted image data for abnormality detection, and outputting the determination result There is disclosed an image forming apparatus having determination means capable of detecting the presence or absence of abnormality of the charging unit based on the determination result of the comparison means.
Further, in Patent Document 4, a plurality of latent image carriers are provided, and a process of transferring an image from each latent image carrier to a transfer body, failure of an optical sensor directed to the transfer body and an image forming apparatus In the image forming apparatus provided with failure detection means for performing prediction, when occurrence of color streaks is predicted, a transfer bias for the transfer body is applied to each one of the latent image carrier, and the transfer body is detected by the failure detection means. An image forming apparatus having a mode for detecting the surface condition of the image forming apparatus is disclosed. In addition, Patent Document 4 also shows that this image forming apparatus can identify an image forming unit of a color in which a sign of an image failure such as a color streak has occurred.

  Furthermore, Patent Document 5 shows an image processing apparatus having an image forming unit that forms an image, and an acquiring unit that acquires a feature amount from a result of reading a chart formed by the image forming unit, and acquired by the acquiring unit The image forming apparatus further includes a determination unit that determines whether a defect is included in the image formed by the image forming unit according to the feature amount and a notification unit that notifies information about the result determined by the determination unit. There is disclosed an image processing apparatus having determination means for determining whether to add an image generated from a result of reading a chart to information to be notified by notification means according to the feature amount acquired by the means.

JP 2004-133081 A JP 2007-334269 A JP, 2008-170549, A JP 2008-292973 A JP, 2016-46595, A

  SUMMARY OF THE INVENTION The present invention provides an image forming apparatus capable of confirming whether or not the cause is in the process after the transfer portion when a defect occurs in an image formed of a toner image.

The image forming apparatus of this invention (A1) is
An image forming unit for forming a toner image;
A transfer unit for transferring the toner image formed by the image forming unit to a recording medium;
A control unit that executes an operation of forming a toner image consisting of two or more types of line patterns with different angles in the image forming unit as a confirmation image and then transferring the toner image onto a recording medium in the transfer unit;
Are provided.

In the image forming apparatus of the invention (A2), in the image forming apparatus of the invention A1, the confirmation image has a line pattern of an angle in which the direction of the lines is along the direction intersecting the conveyance direction of the recording medium. Is configured by applying at least one.
In the image forming apparatus of this invention (A3), in the image forming apparatus of the invention A2, an angle at which the direction of the lines is along the width direction orthogonal to the conveyance direction of the recording medium as the at least one line pattern. The line pattern of is applied.

An image forming apparatus according to the invention (A4) is the image forming apparatus according to any one of the inventions A1 to A3, wherein the control means performs one operation on the toner image having the two or more types of line patterns during the operation. It is configured to be distributed and formed on the recording medium of
In the image forming apparatus of the invention (A5), in the image forming apparatus of the invention A4, the control means, when performing the operation, unevenly distributes a toner image formed of the two or more types of line patterns on one recording medium. It is configured to be formed in a dispersed state without causing it.

  An image forming apparatus according to this invention (A6) is the image forming apparatus according to any one of the inventions A1 to A5, wherein the control unit changes the transfer voltage supplied to the transfer portion during the operation into a plurality of types. The apparatus is configured to output a plurality of recording media on which the toner image has been transferred.

An image forming apparatus according to this invention (A7) is the image forming apparatus according to any one of the inventions A1 to A6, wherein the reading unit reads the confirmation image formed of the toner image formed on the recording medium by the operation; And output means for outputting information of the confirmation image read by the means, wherein the control means operates the reading means and the output means during the operation.
In the image forming apparatus of the invention (A8), in the image forming apparatus of the invention A7, is toner present in a portion other than the line of the line pattern in the information of the confirmation image output from the output means? Detection means for detecting whether or not it is present, wherein the control means operates the reading means and the output means during the operation.

  According to the image forming apparatus of the invention A1, when there is a defect in the image formed of the toner image, it can be confirmed whether the cause is in the process after the transfer portion.

In the image forming apparatus of the invention A2, as compared with the case where the line pattern of the angle at which the direction of the lines is along the direction crossing the conveyance direction of the recording medium is not applied as the confirmation image, the image defect is a transfer portion It can be efficiently confirmed whether the toner is generated due to toner scattering in the following process.
In the image forming apparatus of the invention A3, the image defect is transferred as compared with the case where the line pattern of the angle at which the direction of the lines is along the width direction orthogonal to the conveyance direction of the recording medium is not applied. It is possible to efficiently check whether the toner is generated by toner scattering in the process after printing.

In the image forming apparatus of the invention A4, the image defect is a transfer portion as compared with the case where the control means is not configured to distribute and form a toner image consisting of two or more types of line patterns on one recording medium. It is possible to efficiently check the number of recording media used for the checking function to reduce the number of recording media used for the checking function, as to whether toner is generated due to toner scattering in the subsequent process.
In the image forming apparatus of the invention A5, the image is formed as compared to the case where the control means is not configured to disperse the toner image consisting of two or more types of line patterns without being unevenly distributed on one recording medium. It can be accurately confirmed whether the defect is caused by toner scattering in the process after the transfer portion.

  In the image forming apparatus of the invention A6, when the image defect is generated due to toner scattering at the transfer portion, it is possible to know the presence or absence of the transfer voltage value for improving the image defect.

In the image forming apparatus of the invention A7, the cause of the image defect can be confirmed from the output information of the read confirmation image.
In the image forming apparatus according to Invention A8, as compared with the case where the detection unit is not configured to detect whether the toner is present in the portion other than the line of the line pattern in the information of the confirmation image, The apparatus can accurately determine whether the image defect is caused by toner scattering at the transfer portion.

FIG. 2 is an explanatory view showing a configuration of an image forming apparatus according to Embodiment 1 and the like. FIG. 2 is an enlarged explanatory view showing a configuration of a secondary transfer unit and a fixing unit in the image forming apparatus of FIG. FIG. 2 is a block diagram showing the configuration of part of a control system in the image forming apparatus of FIG. 1; It is explanatory drawing which shows the structural example at the time of dividing roughly the line pattern which comprises the image for confirmation. It is plane explanatory drawing which shows the example of a result of the recording paper in which the image for confirmation obtained when performing confirmation operation | movement 1 by a confirmation function was formed. FIG. 7 is an explanatory perspective view schematically showing a relationship between a toner scattering and a line pattern of a type in which the recording sheet moves to the rear side in the conveyance direction. FIG. 6 is an explanatory view showing a configuration example of a confirmation image formed on a recording sheet. FIG. 8 is an explanatory view showing another configuration example of the confirmation image formed on the recording sheet. FIG. 8 is an explanatory view showing another configuration example of the confirmation image formed on the recording sheet. FIG. 6 is an explanatory plan view showing an example of an image defect generated due to toner scattering. FIG. 7 is an explanatory view showing, in an enlarged manner, an example of a factor causing toner scattering in the image forming apparatus of FIG. 1;

  Hereinafter, modes for carrying out the present invention (hereinafter referred to as "embodiments") will be described with reference to the drawings.

First Embodiment
1 to 3 show an image forming apparatus 1 according to the first embodiment. FIG. 1 shows the configuration of the image forming apparatus 1, FIG. 2 shows an enlarged configuration of the secondary transfer portion and the fixing portion in the image forming apparatus 1, and FIG. 3 shows one of the control systems in the image forming apparatus 1. It shows the configuration of the department.

<Overall Configuration of Image Forming Apparatus>
The image forming apparatus 1 adopts an electrophotographic method, and finally forms an image composed of toner on a recording sheet 9 which is an example of a recording medium, based on image information consisting of characters, photographs, figures, etc. is there.

Then, as shown in FIG. 1, the image forming apparatus 1 has a case 10 having a box-like appearance as a whole, and inside the case 10, a toner composed of toner as a developer is provided. An image forming unit 2 that forms an image, an intermediate transfer unit 3 that holds a toner image formed by the image forming unit 2 by primary transfer and then conveys the image to a secondary transfer position that performs secondary transfer to recording paper 9 A paper feed unit 4 for storing and supplying the recording paper 9 supplied to the secondary transfer position of the unit 3 and a fixing unit 5 for fixing the toner image secondarily transferred by the intermediate transfer unit 3 to the recording paper 9 are arranged. doing.
In the case 10, for example, a support structure portion and an exterior portion are formed using materials such as a support member and an exterior material, and the recording sheet 9 on which an image is formed is discharged and stored on the upper surface portion. A housing surface 12 is provided. An alternate long and short dash line shown in FIG. 1 is a main transport path of the recording sheet 9 inside the housing 10.

Further, the image forming apparatus 1 has an operation display device 14 having an input unit 14a for inputting an instruction, a condition and the like regarding the operation of the image forming apparatus 1, and a display unit 14b for displaying various information such as conditions and status of the operation. A central control unit 6 or the like that collectively controls the operation of the entire image forming apparatus 1 (the above-described devices and the like) is also disposed.
Further, as described later, when a defect occurs in the image formed of the toner image, the image forming apparatus 1 executes an operation for confirming whether the cause is in the process after the secondary transfer portion 38 or not. It has a function.

The image forming unit 2 includes four image forming devices 20Y, 20M, 20C, and 20K that individually form four color toner images of yellow (Y), magenta (M), cyan (C), and black (K). It is done.
Each of the image forming apparatuses 20 (Y, M, C, K) is provided with a photosensitive drum 21 which is rotationally driven in a required direction, as shown in FIG. A charging device 22, an exposure device 23, a developing device 24, a primary transfer device 25, a drum cleaning device 26 and the like are respectively disposed. In FIG. 1, the reference numerals (21 to 26) indicating the main devices constituting the image forming apparatus 20 are all given to the image forming unit 20Y, but the other image forming units 20M, 20C, and 20K are omitted. And only some symbols are attached.

Among them, the photosensitive drum 21 is, for example, a drum type photosensitive member in which an image forming surface having a photodielectric layer (photosensitive layer) made of a photosensitive material is formed on the peripheral surface of a cylindrical or cylindrical conductive base material to be grounded. It is. The photosensitive drum 21 is provided so as to be rotationally driven in the direction indicated by the arrow A by receiving power from a rotation driving device (not shown).
The charging device 22 is, for example, a contact type charging device including a contact member such as a charging roll which is disposed in a state of being driven to rotate in contact with the image forming surface of the photosensitive drum 21 and to which a required charging current is supplied. is there.

The exposure device 23 is, for example, a non-scanning exposure device configured using a light emitting diode, an optical component, and the like. In the exposure device 23, the image processing unit (symbol 15 in FIG. 3) performs required processing of image information input from the outside through the communication unit, the reading device, etc. and image information stored in the internal storage unit. It is input as an image signal separated into each color component (Y, M, C, K) later. The exposure device 23 performs exposure according to the input image signal.
The developing device 24 is, for example, a developing device 24 (Y, M, C, K) that uses a two-component developer containing a toner of one of the four colors (Y, M, C, K) and a magnetic carrier. It is. Further, the developing devices 24 (Y, M, C, K) are used, for example, to charge the toner to the negative polarity to perform reversal development. Further, the developing device 24 (Y, M, C, K) is provided with a developing roll or the like that rotates so as to hold the two-component developer contained in the housing and convey it to the developing area facing the photosensitive drum 21. ing. A developing current in which an alternating current component is superimposed on a direct current component, for example, is supplied between the developing roller and the photosensitive drum 21.

The primary transfer device 25 is, for example, disposed so as to be in contact with the image forming surface portion which is a primary transfer position of the photosensitive drum 21 (in a state via the intermediate transfer belt 31 described later) This is a contact type transfer device provided with a contact member such as a primary transfer roll to which current is supplied.
The drum cleaning device 26 is disposed in contact with the image forming surface portion of the photosensitive drum 21 at least after the primary transfer at the cleaning operation opening of the housing, and scrapes unnecessary matter such as residual toner on the image forming surface. A cleaning member such as an elastic plate to be removed is provided.

The intermediate transfer unit 3 is disposed at a position above the image forming unit 2.
Intermediate transfer portion 3 is arranged to rotate in the direction indicated by arrow B while passing through a primary transfer position facing to primary transfer device 25 of photosensitive drum 21 in imaging device 20 (Y, M, C, K). An intermediate transfer belt 31 is provided.

The intermediate transfer belt 31 is formed into an endless belt shape having a desired thickness and electric resistance value using a material obtained by dispersing a resistance modifier such as carbon on a base material such as polyimide resin or polyamide resin. is there.
The intermediate transfer belt 31 is rotatably supported by being wound around a plurality of support rolls 32a to 32e. The support roll 32a is a drive roll and a secondary transfer backup roll, the support roll 32b is a cleaning backup roll, and the support roll 32c applies a tension to the intermediate transfer belt 31 and a tension and a meander to correct meandering of the intermediate transfer belt 31. As correction rolls, the support rolls 32d and 32e are respectively configured as driven rolls that form and hold the primary transfer surface of the intermediate transfer belt 31 in cooperation.

  The intermediate transfer portion 3 also has a secondary transfer device 35 for secondarily transferring the toner image transferred onto the intermediate transfer belt 31 onto the recording sheet 9, and remains on the outer peripheral surface serving as an image holding surface of the intermediate transfer belt 31. The cleaning device 36 is provided with a belt cleaning device 36 and the like for removing and cleaning unnecessary substances such as toner adhering thereto.

The secondary transfer device 35 is, for example, a contact type including a secondary transfer roll 351 arranged to be in contact with the image holding surface portion supported by the secondary transfer backup roll 32a of the intermediate transfer belt 31 and to be rotated accordingly. Is adopted. Further, the secondary transfer device 35 supplies a required secondary transfer current to one of the secondary transfer roll or the secondary transfer backup roll 32a, and the other is grounded. In the intermediate transfer portion 3, a portion where the intermediate transfer belt 31 and the secondary transfer roll of the secondary transfer device 35 are in contact with each other is a secondary transfer position.
The belt cleaning device 36 is disposed in contact with the image holding surface portion of the intermediate transfer belt 31 at least after the secondary transfer at the opening for cleaning of the housing, and unnecessary substances such as residual toner on the image holding surface. And a cleaning member such as an elastic plate for cleaning the substrate.

The sheet feeding unit 4 is disposed at a position below the image forming unit 2.
The sheet feeding unit 4 is attached to the housing 10 so as to be freely drawn out, and a storage body 41 in which recording sheets 9 of desired size, type, etc. are stacked on the stacking plate 42, and the storage It comprises at least a delivery device 43 for delivering the recording paper 9 one by one from the body 41 to the paper feeding and conveying path. The number of containers 41 and the number of delivery devices 43 may be increased or decreased as necessary.
The recording sheet 9 may be any recording medium that can be transported by a transport path in the housing 10 and that can transfer and fix a toner image. For example, recording that has been cut into a predetermined size can be applied. It is also possible to use special media such as paper, cardboard, such as postcards, and envelopes.

The fixing unit 5 is disposed at a position above the intermediate transfer unit 3.
As shown in FIG. 1 and FIG. 2, the fixing unit 5 rotates in the direction indicated by the arrow inside the case 51 in which the inlet 51 a and the outlet 51 b of the recording paper 9 are formed, and the surface temperature is The heating rotary body 52 in the form of a roll or a belt heated by the heating means so as to be maintained at a predetermined temperature, contacts the follower 52 at a predetermined pressure in a state substantially along the width direction of the heating rotary body 52 At least a pressing rotating member 53 in the form of a rotating roll or a belt is provided.
Further, in the fixing unit 5, a fixing processing unit NP in which the recording paper 9 holding the toner image is introduced and a fixing process (heating and pressing) is performed at a contact portion of the heating rotating body 52 and the pressing rotating body 53. Is configured as. Further, in the case 51, the introduction guide member 54 for guiding the recording sheet 9 from the introduction port 51a to the fixing processing unit NP inside the introduction port 51a, and the recording paper 9 inside the discharge port 51b The discharge guide member 55 which guides the discharge port 51b to the discharge port 51b is provided.

  The image forming apparatus 1 also has a feed transport path Rt1 connecting the paper feed unit 4 and the intermediate transfer portion 3 as a main sheet transport path inside the housing 10, and a secondary transfer position of the intermediate transfer portion 3 A relay conveyance path Rt2 connecting between the fixing unit 5 and the fixing unit 5 and a discharge conveyance path Rt3 connecting between the fixing unit 5 and the paper discharge port 11 of the housing 10 are provided.

  The feed conveyance path Rt1 is a conveyance path for conveying and feeding the recording sheet 9 delivered from the sheet feeding unit 4 to the secondary transfer position of the intermediate transfer unit 3, and is not illustrated with a plurality of sheet conveyance roll pairs 45a, 45b, etc. It comprises a plurality of sheet guide members and the like. The relay conveyance path Rt2 is a conveyance path for conveying the recording sheet 9 after the secondary transfer to the fixing unit 5, and is configured of, for example, a sheet guide member 46. The discharge conveyance path Rt3 is a conveyance path that conveys the recording sheet 9 on which an image is formed after fixation to the discharge storage surface portion 12, and is configured of a discharge roll pair 47 and a sheet guide member (not shown).

  In this image forming apparatus 1, as shown in FIG. 1, the primary transfer device 25 in each of the image forming devices 20 (Y, M, C, K) of the image forming unit 2 and an intermediate portion facing the primary transfer device 25. A portion composed of the transfer belt 31 (and the photosensitive drum 21) constitutes a primary transfer portion 28 in the image forming unit 2. Further, as shown in FIG. 1 and FIG. 2, the portion consisting of the secondary transfer device 35 and the portion of the intermediate transfer belt 31 (and the secondary transfer backup roll 32a) facing the secondary transfer device 35 is an intermediate The secondary transfer unit 38 in the transfer unit 3 is configured.

<Basic image forming operation>
In the image forming apparatus 1, a basic image forming operation described below is performed. Here, an operation in the case of forming a full color image configured by combining toner images of four colors (Y, M, C, K) will be described as an example.

First, in the image forming apparatus 1, when the central control unit 6 receives a request for image forming operation from the outside or the like, in the four imaging devices 20 (Y, M, C, K) constituting the imaging unit 2, Each photosensitive drum 21 is rotated in the direction indicated by the arrow A, and each charging device 22 receives a supply of charging current to generate a contact discharge. As a result, each photosensitive drum 21 is charged to the required polarity (for example, negative polarity) and potential.
Subsequently, each exposure device 23 performs exposure according to the image signal separated into each color component (Y, M, C, K) on the image forming surface of each photosensitive drum 21 after charging. Thereby, electrostatic latent images of respective color components having a predetermined potential are formed on the image forming surface of each photosensitive drum 21.

Subsequently, each developing device 24 (Y, M, C, K) supplies toner of a color (Y, M, C, K) charged to a predetermined polarity (minus polarity) from the developing roll, The developing electric field formed between the developing roll and the photosensitive drum 21 electrostatically adheres to the electrostatic latent image portion of each color component on the image forming surface of the photosensitive drum 21 by receiving the supply of the developing current. As a result, on the image forming surface of each of the photosensitive drums 21, toner images of the corresponding colors among the four colors (Y, M, C, K) are individually formed.
Subsequently, in the primary transfer portion 28 of each of the image forming devices 20 (Y, M, C, K), each primary transfer device 25 receives supply of a primary transfer current to form a primary transfer electric field with the photosensitive drum 21. By doing this, the toner images on the photosensitive drums 21 are primarily transferred to the image holding surface of the intermediate transfer belt 31 in the intermediate transfer portion 3 in order (Y, M, C, K). Further, the drum cleaning device 26 cleans the image forming surface of each photosensitive drum 21 after the primary transfer and the like.

Next, in the intermediate transfer portion 3, the intermediate transfer belt 31 is rotated in the direction indicated by the arrow B in synchronization with the rotation timing of the photosensitive drum 21 in the image forming portion 2, thereby being primarily transferred and held on the image holding surface. The unfixed toner image is conveyed to a secondary transfer position facing the secondary transfer device 35. On the other hand, in the sheet feeding unit 4, after the delivery device 43 delivers the required recording sheet 9 from the storage body 41 to the supply conveyance path Rt1, it feeds the recording sheet 9 to the secondary transfer position of the intermediate transfer unit 3 via the supply conveyance path Rt1. So supply.
Thereafter, in the secondary transfer portion 38 of the intermediate transfer portion 3, the secondary transfer roll 351 or the secondary transfer backup roll 32a of the secondary transfer device 35 receives the supply of the secondary transfer current, and the secondary transfer roll 351 and the intermediate By forming a secondary transfer electric field with the transfer belt 31, the four color toner images on the intermediate transfer belt 31 are secondarily transferred to one side of the recording paper 9. Further, the belt cleaning device 36 cleans the image holding surface of the intermediate transfer belt 31 after secondary transfer and the like.

Next, the recording paper 9 on which the unfixed toner image has been secondarily transferred is separated from the intermediate transfer belt 31 and conveyed so as to be fed to the fixing unit 5 via the relay conveyance path Rt2. In the fixing unit 5, the recording paper 9 is guided by the introduction guide member 54 and introduced into and passed through the fixing processing unit NP which is a contact portion of the heating rotating body 52 and the pressure rotating body 53. Heat and pressure. Thus, the toner forming the toner image is melted under pressure, and the toner image is fixed on the recording sheet 9.
Subsequently, the recording sheet 9 on which the toner image is fixed is guided by the discharge guide member 55 and discharged from the inside of the housing 51 of the fixing unit 5 and then conveyed via the discharge conveyance path Rt3. The sheet is discharged from the sheet discharge port 11 to the outside of the housing 10 and stored in the discharge storage surface portion 12.

  By performing the above operation, one recording sheet 9 having a full color image formed on one side is output. In addition, when a request command for a plurality of image forming operations is received, the image forming operation is similarly repeated by the number of sheets.

  In addition to the above, in the image forming apparatus 1, in the image forming operation described above, a monochrome image is formed by operating any one of the four image forming devices 20 (Y, M, C, K), A combination of two or three of the two imaging devices 20 (Y, M, C, K) can be activated to form a color image other than a full color image.

<Function to check if the cause of the image defect is in the process after the secondary transfer part>
By the way, in the image forming apparatus 1, when the image forming operation is performed, as illustrated in FIG. 10, bleeding in the image GI formed on the recording paper 9, density abnormality, color tone abnormality, unevenness, etc. Image defects 101 and 102 may occur.

  Such image defects occur, for example, when there is local abrasion of the photosensitive drum 21 in the image forming unit 2 or when there is an abnormality in the developing device 24 or when there is toner scattering in the toner image transferred onto the recording paper 9. Do.

Among these, toner scattering may occur at the secondary transfer portion 38. This is because the component parts of the secondary transfer unit 38 are resistance values in addition to parts whose physical properties are known in advance such as the secondary transfer device 35 (secondary transfer roll 351), the intermediate transfer belt 31 and the secondary transfer backup roll 32a. It is difficult to stably obtain appropriate secondary transfer conditions by adding the recording paper 9 having variations in physical properties such as the strength and warping state and charging characteristics.
In addition, toner scattering may occur in the process from the secondary transfer unit 38 to the fixing processing unit of the fixing unit 5. This is because the recording sheet 9 holding the secondary-transferred toner image is not held by the relay conveyance path Rt 2 in the relay conveyance path Rt 2, and the posture (state) at the time of conveyance is likely to change. The paper guiding member 46 in the relay conveyance path Rt2 and the introduction guiding member 54 in the casing 51 of the fixing unit 5 before being introduced to the fixing processing unit NP of the fixing unit 5 due to the fluctuation in the posture during conveyance. Is likely to come into contact with the

  Therefore, in an image forming apparatus adopting an intermediate transfer method such as the image forming apparatus 1, the portion of the secondary transfer portion 38 and the secondary transfer portion 38 to the fixing processing portion of the fixing portion 5 It is considered that there is a possibility that toner scattering may occur in a part of the process up to (which can be said as "the process after the secondary transfer portion").

Incidentally, in the case of the image forming apparatus 1, as illustrated in FIG. 11, the recording paper 9 after the secondary transfer is performed by the secondary transfer unit 38 is transferred to the fixing unit 5 via the relay conveyance path Rt 2. In the process for the fixing processing unit NP, a part of the sheet may strongly contact the sheet guiding member 46 or the introduction guiding member 54 due to the disturbance of the posture during the conveyance.
Further, depending on the charging characteristics of the recording sheet 9, when such a contact occurs, a discharge occurs between the recording sheet 9 and the sheet guiding member 46 or the introduction guiding member 54, whereby the recording sheet 9 is electrostatically charged. The part of the toner constituting the unfixed toner image held by the magnetic attraction may be disturbed in the balance of electrostatic attraction and may be scattered to a position different from the original position.
In FIG. 11, reference numeral 9a denotes a leading end when the recording sheet 9 is conveyed, reference numeral 9b denotes a rear end when the recording sheet 9 is conveyed, reference numeral TG denotes a toner image, and reference numeral Tx denotes scattered toner.

<Configuration of Operation for Forming Confirmation Image>
In the image forming apparatus 1, when a defect is generated in the image formed of the toner image formed on the recording paper 9 by the image forming operation, is the cause of the image defect in a process including the secondary transfer portion 38? It has the following means to confirm the
That is, the image forming apparatus 1 performs an operation of forming a toner image consisting of two or more types of line patterns with different angles in the image forming unit 2 as a confirmation image and transferring the toner image onto the recording paper 9 in the secondary transfer unit 38. The control means 61 to perform is provided.
Hereinafter, the operation performed by the control unit 61 is referred to as a "confirmation operation".

Here, the line pattern of the confirmation image is configured using the pattern of the line screen used in the tone expression of the image processing process. As this line pattern, in addition to this, for example, if it is possible to check the presence or absence of toner scattering, an image (latent image) pattern constituted by a large number of parallel thin line groups is applied. Good.
Further, as illustrated in FIG. 4 and the like, the line pattern of the confirmation image is an element of an angle (for example, an angle α made with the conveyance direction D of the recording sheet 9 or the subscanning direction) indicating the direction of the line. Two or more different line patterns are applied. In addition, it is preferable that two or more types of line patterns having different angles have the same relationship with respect to elements such as line pitch, line width, and color other than the elements of the angles.
Further, from the viewpoint that the confirmation image can efficiently confirm the cause of the toner scattering, etc., at least the line pattern of the angle at which the direction of the lines is along the direction intersecting the conveyance direction D of the recording paper 9 It is configured by applying one.
Furthermore, it is preferable that the confirmation image is formed by distributing a toner image consisting of two or more types of line patterns different in angle on one side of one recording sheet 9, but as described later, two or more types It may be configured to form toner images of a line pattern on one side of the recording paper 9 separately for each type.

  The control unit 61 is a unit (control unit) configured of an arithmetic processing unit, a storage element, an input / output unit, an external storage unit, and the like. Further, the control means 61 is configured to execute a required control operation based on a program and data stored in the storage element (ROM or the like), and particularly in the first embodiment, the above-mentioned confirmation operation is performed. It is configured to earn. Moreover, although the control means 61 is comprised as a part of central control part 6, you may comprise it as an independent means.

  Further, as shown in FIG. 3, the control unit 61 performs an image processing unit 15 that performs necessary image processing on image information input from the outside of the image forming apparatus 1, and an exposure drive unit 16 that drives the exposure device 23. It is connected to the feeding means 17 for supplying a current (voltage) such as the charging current, the developing current, the primary transfer current, the secondary transfer current, and the display portion 14b of the operation display device 14 To send control signals necessary for Further, the control means 61 is connected to the communication unit 19 for communicating information with an external device etc., the input unit 14a of the operation display device 14 etc., thereby obtaining information necessary for control operation. There is.

Furthermore, the control means 61 is configured to execute the image forming operation by transmitting the image information (signal) of the confirmation image from the image processing unit 15 to the exposure driving unit 16 when executing the above-mentioned confirmation operation. .
The image forming operation when executing the confirmation operation is different in that the image to be formed becomes the confirmation image, but the same conditions as the conditions for forming the normal image are applied to the other image forming conditions. Be done. It is preferable that the confirmation image formed of the line pattern is formed with a halftone density from the viewpoint that the presence or absence of the toner scattering is easily confirmed, and the conditions for adjusting the density (for example, the exposure apparatus The condition of the light amount at the time of exposure may be changed to a setting slightly different from the condition for forming a normal image.

The image information of the confirmation image (line pattern) to be applied in the confirmation operation is stored in advance in a storage unit of the image processing unit 15 or a storage element of the control unit 61 as specific image data. The control unit 61 controls to transmit the image data (signal) of the stored confirmation image to the exposure device 23 through the exposure driving unit 16 when the image forming operation for the confirmation operation is performed.
In the confirmation operation, when there are a plurality of imaging devices 20 that form a toner image, one or more of the plurality of imaging devices 20 (Y, M, C, and K) are activated and performed once or more. It will be done several times.
Further, the recording sheet 9 used in the confirmation operation is the recording sheet of the maximum size which is the target of use in the image forming apparatus 1 or the recording sheet of which the feed width at the time of conveyance is the largest.

Then, the control means 61 obtains, for example, the information instructed by the service engineer (service man) or the user by selecting the execution mode of the confirmation operation from the input unit 14a of the operation display device 14 for the confirmation operation. , Is configured to run.
In this case, the execution mode of the confirmation operation is displayed, for example, as a screen for selection instruction on the display unit 14 b of the operation display device 14. In addition, the execution of the confirmation operation by the instruction of the service engineer or the like may be performed periodically, for example, according to the progress status of the use frequency based on the information such as the number of image formations or when an image defect occurs. Make it

  When the confirmation operation is performed, the service engineer or the like visually checks the confirmation image formed on the recording paper 9 by the confirmation operation to confirm the presence or absence of the toner scattering and the state.

The line patterns forming the confirmation image are roughly classified into three types of patterns as shown in FIG.
That is, the first one-line pattern P1 of angle α1 at which the angle α with the conveyance direction D of the recording paper 9 of the multi-line ML makes approximately 0 ° (0 ° or 0 ° ± 1 °), and the conveyance direction of the multi-line ML The second common line pattern P2 of an angle α2 at which the angle α forms an angle α of approximately 90 ° (90 ° or 90 ° ± 1 °) and the angle α formed with the conveyance direction D of the parallel line ML are 0 ° <α <± There are three types with the third line pattern P3 of the angle which becomes a value in the range of 90 °.

The third main line pattern P3 can be further divided into the following types.
That is, a line pattern P3a of an angle α3 (+ angle) at which the direction of the line ML is inclined to the left in the conveyance direction D of the recording sheet 9, and the direction of the line ML is the conveyance direction D of the recording sheet 9. Divided into a line pattern P3b of an angle .alpha.4 (an angle on the-side) which is inclined to the right of. In addition, the third main line patterns P3a and P3b can be made to have many more main line patterns by making the angles α3 and α4 different.

  Incidentally, the angle α1 of substantially 0 ° is an angle when the direction of the lines ML is in the direction along the conveyance direction D of the recording sheet 9. Further, the angle α2 of about 90 ° is an angle when the direction of the lines ML is along the width direction (axial direction) E orthogonal to the conveyance direction D of the recording sheet 9. Furthermore, the angles α3 and α4 in the range of 0 ° <α <± 90 ° are angles when the direction of the line ML is along the width direction E orthogonal to the conveyance direction D of the recording sheet 9. . Further, the angle α2 of about 90 ° is also a part of the angle when the direction of the lines ML is along the direction intersecting the conveyance direction D of the recording sheet 9.

Then, two or more types of line patterns with different angles applied as the confirmation image are selected from the following three combinations and applied.
The first is a combination in which a plurality of line patterns P1, P2 and P3 each consisting of the three roughly classified angles (ranges) described above are combined. The second is a combination combining the first and second line patterns P1 and P2 and the subdivided third and fourth line patterns P3a and P3b. The third is a combination in which one or both of the third line patterns P3a and P3b are combined such that the angles α (α3 and α4) are different from each other.

<Check operation 1>
In the image forming apparatus 1, when the service engineer or the like selects and instructs the execution mode of the confirmation operation from the input unit 14a of the operation display device 14, the control unit 61 executes the confirmation operation 1 exemplified below.

The confirmation operation 1 at this time is performed by operating one of the four imaging devices 20 (Y, M, C, K). Here, as a representative, the confirmation operation in the case where the black K image forming apparatus 20K is operated is described.
In addition, the confirmation operation 1 at this time is a confirmation image including only the first line pattern P1 illustrated in FIG. 4A (a line pattern whose angle follows the conveyance direction D) as the confirmation image. 4B is adopted as a confirmation image consisting only of the second parallel line pattern P2 illustrated in FIG. 4B (the parallel line pattern of the angle along the width direction E where the angle intersects the transport direction D). Further, the confirmation operation 1 is configured to form a confirmation image to which the above-mentioned two types of line patterns are applied substantially over the entire area of one side of the two recording sheets 9.

Then, when the check operation 1 is actually started by the control operation of the control means 61, in the imaging device 20K, the charging potential of the image forming surface of the rotating photosensitive drum 21 is the same as that when forming a normal image. After being charged so as to become, the exposure device 23 performs exposure based on the image information of the confirmation image transmitted from the image processing unit 15. Thus, two electrostatic latent images corresponding to the first and second line patterns P1 and P2 are sequentially formed on the image forming surface of the photosensitive drum 21.
Subsequently, the developing device 24K develops two electrostatic latent images with black toner. Thus, two black toner images as confirmation images corresponding to the first and second line patterns P1 and P2 are sequentially formed on the image forming surface of the photosensitive drum 21.

Next, two black toner images, which are confirmation images on the image forming surface of the photosensitive drum 21 in the image forming apparatus 20K, are sequentially primarily transferred onto the intermediate transfer belt 31 rotated by the intermediate transfer unit 3 in the primary transfer unit 28. After being conveyed to the secondary transfer position, secondary transfer is separately and sequentially performed on the two recording sheets 9 in the secondary transfer unit 38.
Subsequently, the two recording sheets 9 on which the two black toner images as the confirmation image are transferred are the intermediate transfer belt 31 rotating in the secondary transfer portion 38 and the secondary transfer roll 351 of the secondary transfer device 35. The sheet is conveyed so as to be introduced into the inside of the case 51 of the fixing unit 5 via the relay conveyance path Rt2 by receiving the conveyance force in a state of being sandwiched between the two.
Subsequently, after the two black toner images as the confirmation image are separately fixed on the two recording sheets 9 in the fixing unit 5, the two images on which the confirmation image including the two black toner images is formed are formed. The recording paper 9 is sequentially conveyed via the discharge conveyance path Rt3 and finally stored in the discharge storage surface portion 12 so as to be discharged.

Thus, the confirmation operation 1 by the image forming operation in which the image forming device 20K is operated is completed.
In addition, when the confirmation operation 1 is set to be performed by independently operating the image forming devices 20 (Y, M, C) of the remaining colors, the confirmation by the operation of the black image forming device 20 K After the operation step of the operation 1 is completed, the remaining color image forming devices 20 (Y, M, C) are independently operated in sequence as in the case where the image forming device 20 K is operated alone. To be executed.

  When the confirmation operation 1 is executed, the service engineer or the like sees the confirmation image G formed of the line pattern formed on each of the two recording sheets 9 finally output, and the presence or absence of the image defect And the differences in the manifestation of image defects.

  In the confirmation operation 1, for example, as shown in FIG. 5, the recording paper 9 on which the confirmation image Ga formed of the first line pattern P1 of the angle α1 where the direction of the lines is along the transport direction D is formed (A) in the figure and the recording sheet 9 on which the confirmation image Gb composed of the second line pattern P2 having an angle α2 in which the direction of the lines is along the width direction E is formed ((b) in FIG. And are output.

  From a comparison of the confirmation images Ga and Gb at this time, it is confirmed that no image defect (103) is generated in the confirmation image Ga as shown in FIG. 5A, while the confirmation image Gb is confirmed. As shown in FIG. 5B, it was confirmed that an image defect 103 was generated due to toner scattering. In addition, it is confirmed that the image defect 103 at this time is generated in the portion on the rear side in the conveyance direction D of the recording sheet 9 in the confirmation image Gb.

  If the cause of the image defect 103 is spattering of toner generated in the process after the secondary transfer portion 38, the spattering of the toner in the conveyance direction of the recording paper 9 is exemplified as illustrated in FIG. Since it tends to occur to move to the rear side of D, it is considered that the result is divided into the case where the spatter is likely to be manifested and the case where the spatter is hardly manifested.

That is, in the case of the confirmation image Gb configured by the second parallel line pattern P2 of the angle α2 where the direction of the lines is along the width direction E, as illustrated in FIG. The toner Ta splattered to the side is relatively more likely to be landed in the non-image area (white paper area between the lines and lines) which is not the image area of lines in the direction along the width direction E. Scattering is more likely to be realized. In this case, the result of the scattering can be easily viewed.
On the other hand, in the case of the confirmation image Ga formed of the first line pattern P1 having an angle such that the direction of the lines is along the transport direction D, the back side is exemplified as illustrated in FIG. Since the scattered toner Ta is relatively frequently present again on the image portion of the line along the transport direction D, the scattered scattering of the toner is less likely to be realized. In this case, it becomes difficult to visually recognize the result of the scattering.

For this reason, as in the confirmation operation 1, the confirmation operation is performed by forming the confirmation image Ga consisting of only the 1st line pattern P1 and the confirmation image Gb consisting only of the 2nd line pattern P2 as the confirmation image. If you do, you can check the following:
That is, as illustrated in FIG. 5, while the image defect 103 due to the toner scattering is generated in the confirmation image Gb (see FIG. 5B), it is not generated in the confirmation image Ga. The result (see FIG. 5A) may be obtained. At this time, it can be confirmed that the cause of the image defect 103 is in the process after the secondary transfer portion 38 (in fact, it is due to the occurrence of toner scattering).

In addition, when the confirmation operation 1 is performed, the image defect 103 may not occur in any of the confirmation images Ga and Gb. In this case, it can be seen that the cause of the image defect 103 is not in the process after the secondary transfer portion 38.
When the confirmation operation 1 is executed, the image defect 103 may occur in the confirmation image Ga and may not occur in the confirmation image Gb. In this case, it is understood that the image defect 103 is caused by the scattering of toner in the axial direction E.

<Check operation 2>
Next, the confirmation operation 2 executed by the control means 61 will be described.

  As illustrated in FIGS. 7 to 9, the confirmation operation 2 includes a toner image (a combination of two or three or more of P1, P2, and P3) for confirmation (for confirmation). The image is formed so as to be distributed and formed on one side of one recording sheet 9. When the confirmation image having such a configuration is adopted, the confirmation operation can be shortened and the number of recording sheets 9 used can be reduced as compared with the confirmation operation 1.

In the confirmation image Gc illustrated in FIG. 7A, the single line is conveyed to a divided area having a long planar shape along the width direction E in which the conveyance direction D is divided into plural on one side of the recording paper 9 A confirmation image formed of a first line pattern P1 having an angle along the direction D and a confirmation image formed of a second line pattern P2 having an angle along which the direction of the line is along the width direction E are It is formed to be alternately arranged before and after the transport direction D.
When the confirmation image Gc is formed as the confirmation operation 2, for example, the image defect 103 (FIG. 5B) due to the toner scattering generated in the above-mentioned confirmation operation 1 is on the rear side portion of the recording paper 9 in the transport direction D. It will appear in the confirmation image consisting of the second line pattern P2 formed at intervals. On the other hand, when the confirmation image Gc is employed, the confirmation image formed of the second parallel line pattern P2 is formed at an interval in the transport direction D. Therefore, an image defect due to toner scattering is unevenly distributed in the transport direction D When the defect occurs in a portion where there is a problem, there is a possibility that a part of the image defect (image defect present in the confirmation image portion consisting of the first line pattern P1) can not be confirmed.

The confirmation image Gd illustrated in FIG. 7B has a first parallel line pattern in a divided area having a flat planar shape along the transport direction D in which the width direction E is divided into plural on one side of the recording paper 9 The confirmation image formed of P1 and the confirmation image formed of the second parallel line pattern P2 are formed to be alternately arranged on the left and right of the width direction E.
In the case where the confirmation image Gd is formed as the confirmation operation 2, for example, the image defect 103 (FIG. 5B) due to the toner scattering generated in the above-mentioned confirmation operation 1 is a confirmation image of the second line pattern P2. Of these, it appears in the part on the rear side in the transport direction D. On the other hand, when this confirmation image Gd is adopted, since the confirmation images formed of the second parallel line pattern P2 are formed at intervals in the width direction E, the image defects due to toner scattering are unevenly distributed in the width direction E When it occurs, there is a possibility that a part of the image defect can not be confirmed.

The confirmation image Ge illustrated in FIG. 8A is divided into a plurality of divisions in the transport direction D on one side of the recording paper 9 and is divided into a plurality of divided areas having a long planar shape along the width direction E. A confirmation image consisting of the second parallel line pattern P2 and a confirmation image consisting of the third parallel line pattern P3a at an angle such that the direction of the lines obliquely intersects the transport direction D; It is formed to be alternately arranged before and after the transport direction D.
When the confirmation image Ge is formed as the confirmation operation 2, for example, the image defect 103 (FIG. 5B) due to the toner scattering generated in the above-mentioned confirmation operation 1 is on the rear side of the recording paper 9 in the transport direction D. It appears in the confirmation image formed of the second and third line patterns P2 and P3a formed at intervals.
Further, the image for confirmation Ge appears as an image defect due to toner scattering in the image for confirmation formed of the third line pattern P3a, so that the image defect due to toner scattering occurs in a portion unevenly distributed in the transport direction D. Even if it does, compared with the said confirmation image Gc (FIG. 7 (a)), the ratio which can not confirm a part of the image defect can be reduced.

The confirmation image Gf illustrated in FIG. 8B is formed on one side of the recording sheet 9 in a diagonal division area having a flat planar shape in which the transport direction D is diagonally divided into a plurality and the diagonal direction is long. The confirmation image formed of the line pattern P1 and the confirmation image formed of the second line pattern P2 are formed to be alternately arranged before and after the transport direction D or to the left and right of the width direction E.
In the case where the confirmation image Gf is formed as the confirmation operation 2, for example, the image defect 103 (FIG. 5B) due to the toner scattering generated in the above-mentioned confirmation operation 1 is a confirmation image of the second line pattern P2. Of these, it appears in the part on the rear side in the transport direction D.
Further, the confirmation image Gf is formed in a shape in which the confirmation image formed of the second parallel line pattern P2 obliquely extends in the conveyance direction D (width direction E), so that an image defect due to toner scattering is generated. Even in the case where the uneven distribution occurs in the width direction E, it is possible to reduce the ratio in which a part of the image defect can not be confirmed as compared with the confirmation image Gd (FIG. 7B).

The confirmation image Gj illustrated in FIG. 9 is divided into a plurality of equally divided areas, each of which has a quadrangular planar shape of the same size by dividing the conveyance direction D and the width direction E into a plurality of one side of the recording paper 9. The confirmation image formed of the line pattern P1 and the confirmation image formed of the second parallel line pattern P2 are formed alternately (in a checkered pattern) before and after the transport direction D and to the left and right of the width direction E. .
In the case where the confirmation image Gj is formed as the confirmation operation 2, for example, the image defect 103 (FIG. 5B) due to the toner scattering generated in the above-mentioned confirmation operation 1 is a confirmation image of the second line pattern P2. Of these, it appears in the part on the rear side in the transport direction D.
Further, as in this confirmation image Gj, a confirmation image formed in a state in which two or more types of line patterns with different angles are dispersed without being unevenly distributed on one side of one recording sheet 9 is adopted. In this case, since the confirmation image consisting of the second parallel line pattern P2 is dispersed almost equally in both the transport direction D and the width direction E, the image defect due to the toner scattering is either in the transport direction D or in the width direction E. Even if uneven distribution occurs, it can be efficiently and accurately confirmed whether the cause of the image defect is in the process after the secondary transfer.

As the toner scattering, one or both of the toner scattering generated so as to move to the rear side in the transport direction D and the toner scattering generated so as to move in the width direction E are in the transport direction D and the width direction E. It may occur unevenly in one or both.
However, even in this case, in the confirmation operation by the confirmation function, for example, two or more types of line patterns with different angles as illustrated in FIG. 9 are dispersed without being unevenly distributed to one side of one recording sheet 9. By adopting the confirmation image Gj formed in the irregular state, whether or not the cause of the image defect caused by the toner scattering is the process after the secondary transfer portion 38 can be accurately and efficiently confirmed.

Second Embodiment
In the image forming apparatus according to the second embodiment, the secondary transfer voltage supplied from the power supply unit 17 to the secondary transfer unit 38 when the confirmation operation by the control unit 61 is performed in the image forming apparatus 1 according to the first embodiment. The plurality of types of recording paper 9 on which the toner image has been transferred to form a confirmation image are output.

  In this image forming apparatus, when the execution mode of the confirmation operation is selected and instructed from the input unit 14a of the operation display device 14 by a service engineer or the like, the control unit 61 performs the confirmation operation of the secondary transfer unit 38 from the power supply unit 17. The secondary transfer voltage supplied to the secondary transfer roll 351 or the secondary transfer backup roll 32a is controlled to be changed to a plurality of types.

Then, in the checking operation at this time, the toner image of the same confirmation image is secondarily transferred onto a plurality of recording sheets 9 under different secondary transfer conditions, and then fixed on each recording sheet 9 by the fixing unit 5 As done. Thereby, in this confirmation operation, finally, a plurality of recording sheets 9 on which the same confirmation image is formed are obtained.
As the secondary transfer voltage to be changed at this time, for example, a normal secondary transfer voltage applied at the time of a normal image forming operation and a different type in which the normal transfer voltage is increased or decreased by a required voltage. A combination of secondary transfer voltage is applied.

When performing such a confirmation operation, when looking at a plurality of recording sheets 9 on which the same confirmation image is formed, the state of the occurrence of the image defect caused by the scattering of toner should be confirmed as follows. Can.
That is, although it is confirmed that the image defect due to the toner scattering is revealed in the confirmation image, the result is that it is not revealed when the different secondary transfer voltage is supplied despite the same confirmation image. May be obtained. In this case, if the secondary transfer voltage at that time is adopted to perform an image forming operation for forming a normal image, an image without toner scattering can be formed at the secondary transfer portion 38. As a result, it can be confirmed that there is a secondary transfer voltage value that improves the image defect at this time.

Third Embodiment
In the image forming apparatus 1 according to the third embodiment, in the image forming apparatus 1 according to the first and second embodiments, the reading means 71 for reading the confirmation image formed on the recording paper 9 by the confirmation operation, and the reading means 71 An output unit 72 for outputting information of the read confirmation image is added. The reading means 71 and the output means 72 are communicably connected to the control means 61 as shown by a two-dot chain line in FIG. 3, and are operated by the control means 61 at the time of confirmation operation.

When the image forming apparatus 1 is configured as a copying machine in which a document reading device is provided, the reading device 71 can use the document reading device as a reading device. And an image reading sensor or the like disposed between the sheet discharge port 11 and reading the confirmation image on the recording sheet 9 discharged from the fixing unit 5.
The output means 72 may be any one that can finally output the information of the confirmation image read by the reading means 71 to a required output destination automatically or based on a selection instruction. Although such output means 72 may be constructed as a dedicated component part, for example, after the information is temporarily stored in the storage device, the information is transmitted as a part of the control function of the control means 61. It may be configured. The output destination is the display unit 14 b of the operation display device 14 or an information terminal such as a user of a user or a service engineer connected to the image forming apparatus 1 via the communication unit 19.

In this image forming apparatus, after the confirmation operation by the control unit 61 is performed to obtain the recording sheet 9 on which the confirmation image is formed, the reading unit 71 reads the confirmation image formed on the recording sheet 9. Information on the confirmation image read by the reading unit 71 is output from the output unit 72 to a desired output destination automatically or by the selection instruction of the person who instructed the confirmation operation.
Then, when the information of the confirmation image read at this time is configured to be output to the display unit 14b of the operation display device 14 by the control operation of the control means 61, for example, the person who instructed the confirmation operation By looking at the read image of the confirmation image displayed on the display unit 14b, it is possible to confirm the presence or absence of the image defect and the difference in the manifestation of the image defect.
Therefore, if this image forming apparatus is used, a person who instructs the confirmation operation can obtain the result of the confirmation image as the information of the read image, and moreover, based on the information of the image, it is possible to scatter the toner. Whether or not the cause of the image defect caused is the process after the secondary transfer portion 38 can be efficiently confirmed.

  Further, in the image forming apparatus according to the third embodiment, detection is performed to detect whether toner is present in a portion other than the line of the line pattern in the information of the confirmation image output from the output means 72. Means 75 (FIG. 3) may be provided. The detection means 75 is communicably connected to the control means 61 as shown by a two-dot chain line in FIG. 3, and is operated by the control means 61 at the time of confirmation operation.

  The detection means 75 has a function of performing image analysis. In addition, when the detection means 75 detects that toner is present in portions other than the lines of the line pattern in the information of the confirmation image, it is presumed that the toner is scattered. Do. In addition, the detection means 75 may analyze the distribution of toner in portions other than the line, and detect the toner scattering state.

The detection result obtained by the detection means 75 is transmitted to the display unit 14b of the operation display device 14 and displayed, for example, by the control operation of the control means 61, or the image forming apparatus 1 and the communication unit 19 are It is configured to be transmitted to an information terminal such as a personal computer of a user or service engineer connected via the network.
Therefore, if this image forming apparatus is used, it is possible to automatically obtain information on the presence or absence of toner scattering in the confirmation image as the detection result of the detection means 75, and the image defect is in the process after the secondary transfer portion 38. The apparatus can accurately determine whether the toner is generated by the toner scattering.

Other Embodiments
In the first to third embodiments, the image forming unit 2 is positioned below the intermediate transfer unit 3 as the color image forming apparatus adopting the intermediate transfer method, and the position above the intermediate transfer unit 3 illustrated by the fixing unit 5. Although the configuration example which consists of the relationship arrange | positioned to each is shown, about the arrangement relationship, it is not limited to the configuration example.

  In the first to third embodiments, the color image forming apparatus adopting the intermediate transfer method is exemplified. However, as the image forming apparatus, the toner image is directly transferred from the electrostatic latent image holder such as the photosensitive drum to the recording sheet. The image forming apparatus may be a color image forming apparatus or a single-color image forming apparatus adopting a direct transfer method. An image forming apparatus adopting this direct transfer method is provided with a transfer unit for directly transferring a toner image of a normal image formed on an electrostatic latent image holder in an image forming unit and a confirmation image to a recording sheet. Become.

1 ... image forming apparatus 2 ... imaging unit 9 ... recording paper (an example of recording medium)
38 ... secondary transfer unit (an example of a transfer unit)
61 Control means 17 Feeding means 71 Reading means 72 Output means 75 Detection means P1 to P3 Line pattern α α Line angle D D Transport direction E Width direction Ga to Gj Confirmation image

Claims (8)

An image forming unit for forming a toner image;
A transfer unit for transferring the toner image formed by the image forming unit to a recording medium;
A control unit that executes an operation of forming a toner image consisting of two or more types of line patterns with different angles in the image forming unit as a confirmation image and then transferring the toner image onto a recording medium in the transfer unit;
An image forming apparatus comprising:   The image forming apparatus according to claim 1, wherein the confirmation image is configured by applying at least one line pattern of an angle in which the direction of the lines is a direction along the direction intersecting the conveyance direction of the recording medium. .   3. The image forming apparatus according to claim 2, wherein the at least one line pattern is an angled line pattern in which the direction of the line is a direction along the width direction orthogonal to the conveyance direction of the recording medium.   4. The image forming apparatus according to any one of claims 1 to 3, wherein the control means is configured to distribute and form a toner image consisting of the two or more types of line patterns on one recording medium during the operation. Image forming apparatus.   5. The image forming apparatus according to claim 4, wherein the control means is configured to form a toner image consisting of the two or more types of line patterns in a dispersed state without being unevenly distributed to one recording medium during the operation. Image forming device.   The control means is configured to change a transfer voltage supplied to the transfer portion into a plurality of types during the operation to output a plurality of recording media on which the toner image has been transferred. One of the five image forming apparatuses. Reading means for reading a confirmation image comprising the toner image formed on the recording medium by the operation;
An output unit that outputs information of the confirmation image read by the reading unit;
Equipped with
The image forming apparatus according to any one of claims 1 to 6, wherein the control unit operates the reading unit and the output unit during the operation. The information processing apparatus further comprises detection means for detecting whether or not toner is present in a portion other than the lines of the line pattern in the information of the confirmation image output from the output means.
The image forming apparatus according to claim 7, wherein the control unit operates the detection unit during the operation.

Images