JP2016114778A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a situation that an image forming apparatus becomes unavailable in a long time when an abnormal sound in the device is detected.SOLUTION: An image forming apparatus 100 includes: an abnormal sound detection part 106b for determining whether or not an operation sound in each of one or more units in the device is an abnormal sound; a scanner part for reading a formed printed matter; an image inspection part 106c for determining the presence/absence of the defect of print quality from the read image of the printed matter; and an image formation control part 106d for performing the control of the continuation or non-continuation of image formation on the basis of a determination result from the image inspection part 106c under such a condition that it is determined that the operation sound is the abnormal sound by the abnormal sound detection part 106b.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an image forming apparatus.

  In the abnormal sound diagnosis apparatus of the image forming apparatus, it is determined whether or not the acoustic data collected by the sound collecting microphone installed in the image forming apparatus is an abnormal sound. A system for controlling the drive to stop is already known.

  As an example, Patent Document 1 discloses that the operation sound of the apparatus is collected using a microphone disposed inside the apparatus, the collected analog form sound is converted into a digital form sound, and the converted digital form sound is obtained. Describes an image forming apparatus that determines that the sound is abnormal and stops driving when the sound is louder than a preset threshold sound.

  However, in the conventional system, after the device stops operating, the user contacts the management company, etc., and then the service staff replaces or repairs the parts caused by the abnormal sound and the device is restored again. There is a problem that it takes time.

The present invention has been made in view of the above conventional problems. Even if an abnormal sound is detected in the image forming apparatus, the image formation can be continued if the abnormal sound does not lead to an image defect.
Accordingly, an object of the present invention is to reduce a situation in which the apparatus cannot be used for a long time even if an abnormal sound in the image forming apparatus is detected.

  The present invention is an image forming apparatus having an operation sound acquisition unit that acquires operation sounds of each of one or more units in the apparatus, and each of the units in the apparatus acquired by the operation sound acquisition unit. An abnormal sound detection unit that determines whether or not the sound is abnormal, a scanner unit that reads a printed material formed by the image forming apparatus, and an image inspection unit that determines whether there is a print quality defect based on a read image of the printed material And an image formation control unit that performs continuation control or non-continuation control of image formation based on the determination result in the image inspection unit on the condition that the abnormal sound detection unit determines that the noise is abnormal. The image forming apparatus is characterized.

  According to the present invention, even if an abnormal sound in the image forming apparatus is detected, it is possible to reduce a situation in which the apparatus cannot be used for a long time.

1 is a diagram schematically showing a configuration of a system of an image forming apparatus according to a first embodiment of the present invention. FIG. 2A is a block diagram illustrating a hardware configuration example of the image forming apparatus of the present embodiment, and FIG. 2B is a functional block diagram of an inspection unit of the image forming apparatus. It is a block diagram which shows the structure of an operation sound acquisition part. It is a block diagram which shows the structure of an abnormal sound detection part. It is a figure which shows the example of a conversion which converts sound data into frequency (f1-f5) information, and is the figure which showed the power (dB) of sound data on the vertical axis | shaft, and showed the frequency on the horizontal axis. It is a block diagram which shows the structure of an image inspection part. It is a flowchart which shows the procedure of an image quality inspection process. It is a flowchart which shows the procedure of the test | inspection process of the presence or absence of a wrinkle pixel. It is a flowchart which shows the procedure of a process of an image formation control part. It is a flowchart which shows the procedure of the process in the image test | inspection part of 2nd Embodiment. FIG. 10 is a flowchart illustrating a processing procedure of an image formation control unit in a third embodiment. A display example of occurrence of abnormality displayed on the display device is shown. FIGS. 13A and 13B are diagrams illustrating a configuration of a scanner that reads an image for inspecting whether or not wrinkles are generated in a print output according to a fourth embodiment, FIG. 13A is a configuration diagram thereof, FIG. 13B is a plan view, and FIG. FIG. FIG. 14 is a diagram schematically showing two images of a document captured by the lamp irradiation method shown in FIG. 13. 14A is a side view of the scanner, FIG. 14B is a scanned image, and FIG. 14C is a scanned image 1 in the upper row and a scanned image 2 in the lower row. FIG. 10 is a diagram illustrating a configuration of a scanner that reads an image in order to check whether or not wrinkles have occurred in a print output according to a fifth embodiment. 15A is a plan view of the scanner, and FIG. 15B is a side view seen from the direction of the arrow SV in FIG. 15A. FIG. 10 is a diagram illustrating a configuration of a scanner that reads an image in order to check whether or not wrinkles are generated in a print output according to a sixth embodiment. 16A is a plan view of the scanner, FIG. 16B is a side view seen from the perspective SV1 in FIG. 16A, and FIG. 16C is a side view seen from the perspective SV2 in FIG. 16A.

Hereinafter, the present invention will be described with respect to embodiments thereof, but before that, the features of the present invention will be described first.
The feature of the present invention is that when abnormal sound is detected in the image forming apparatus, the paper output is read by a scanner, and the image data read is used to detect a defect in the image. The point is to continue image formation.
Here, the image forming apparatus refers to a general apparatus having a function of forming an image, such as a copying machine, a facsimile machine, a multifunction machine, and a printer.

Next, embodiments of the present invention will be described with reference to the drawings.
First Embodiment <System Configuration>
FIG. 1 is a diagram schematically showing a configuration of a system of an image forming apparatus according to the first embodiment of the present invention. The configuration of this system is common to other embodiments.
As shown in the figure, this system includes, for example, a scanner 120 and an image forming apparatus 100 connected by a predetermined data transmission path (for example, “network cable”, “serial and parallel cable”, etc.) 110.
The scanner 120 is a known reading device that optically reads a printed material and acquires a read image, and acquires read images of both the printed surface and the back surface of the printed material.
The image forming apparatus 100 is configured as an information processing apparatus that controls image formation by detecting abnormal sound in the apparatus and inspecting the print quality of printed matter.

FIG. 2A is a block diagram illustrating a hardware configuration example of the image forming apparatus 100 of the present embodiment, and FIG. 2B is a functional block diagram of an inspection unit of the image forming apparatus.
As shown in FIG. 2A, the image forming apparatus 100 includes an input device 101, a display device 102, a ROM (Read Only Memory) 103, a RAM (Random Access Memory) 104, an HDD (Hard Disk Drive) 105, a CPU (Central Processing Unit). ) 106, interface device 107, etc., which are connected to each other by bus B.
As shown in FIG. 2B, the inspection unit of the image forming apparatus 100 includes an operation sound acquisition unit 106a, an abnormal sound detection unit 106b, an image inspection unit 106c, and an image formation control unit 106d, all of which are a CPU 106, a ROM 103, and a RAM 104. It is comprised by the function implementation means implement | achieved with the computer comprised by.

<Abnormal noise detector>
Next, the operation sound acquisition unit 106a and the abnormal sound detection unit 106b for detecting the abnormal sound will be described.
First, the operation sound acquisition unit 106a will be described with reference to FIG.
FIG. 3 is a block diagram illustrating a configuration of the operation sound acquisition unit 106a.
The operation sound acquisition unit 106a includes an acquisition control unit 106a (1), and is connected to the A unit 201, the B unit 202, and the C unit 203 in the main body device via the input / output interface 106a (2). .
Here, the units 201 to 203 are, for example, (1) A unit as a paper transport unit 201 having a transport roller for transporting recording paper from the paper feed tray to the main body, and (2) B unit as an electrostatic latent image. A developing unit 202 having a photoconductive drum for forming a (3) C unit, a fixing unit 203 having a fixing roller that is heated to a predetermined temperature by a heater provided therein and performs a fixing process. Microphones 204 to 206 are connected to these units 201 to 203 as sound collecting means.

In the figure, reference numerals 207 to 209 denote drive motors of the units 201 to 203, respectively. Here, 207 is a drive motor for the paper conveying roller, 208 is a drive motor for the photosensitive drum, and 209 is a drive motor for the fixing roller.
The units are three units of A to C units 201 to 203, but more units may be connected together with a microphone as long as the units operate by a driving source.
The acquisition control unit 106a (1) accumulates the sound data acquired by the units 201 to 203 in the RAM 104 corresponding to the operation sound storage unit of the present invention via the bus B.

Next, the abnormal sound detection unit 106b will be described with reference to FIG.
FIG. 4 is a block diagram illustrating a configuration of the abnormal sound detection unit 106b.
The abnormal sound detection unit 106b includes an abnormality determination unit 106b (1) and a spectrum analyzer 106b (2).
The abnormality determination unit 106b (1) reads the sound data collected by the operation sound acquisition unit 106a and stored in the RAM 104, and sends the sound data to the spectrum analyzer 106b (2). The spectrum analyzer 106b (2) analyzes the transmitted sound data and converts the sound data into frequency information (here, information of the frequencies f1 to f5 shown in FIG. 5).

FIG. 5 is a diagram illustrating a conversion example in which sound data is converted into frequency (f1 to f5) information, and is a diagram illustrating the power (dB) of sound data on the vertical axis and the frequency on the horizontal axis. .
The abnormality determination unit 106b (1) reads sound information (frequency information) during normal image forming operation of the image forming apparatus 100, which is stored in advance in the ROM 103 corresponding to the operation sound storage unit of the present invention. The presence or absence of abnormality is determined by comparing with the frequency information converted into.

Here, the presence / absence of abnormality is determined by calculating the difference between the frequency information obtained by converting the collected sound data and the frequency information during normal operation, and the difference value is set to a predetermined threshold value (first value). Judgment is made based on whether the value is equal to or greater than a threshold value.
The calculation of the difference value DIF of the frequency (f1 to f5) information is performed based on the following formula, for example.
DIF = SQRT (√) ((H (f1) −R (f1)) ² + (H (f2) −R (f2)) ² + (H (f3) −R (f3)) ² + (H (f4 ) − R (f4)) ² + (H (f5) −R (f5)) ² )
However, H (fx) represents the power value at the frequency fx of the collected sound data. R (fx) represents a power value at the frequency fx during normal operation.
SQRT (√) represents the square root of the value of the arithmetic expression in (√).
When the calculated difference value DIF of the frequency information exceeds the first threshold value, it is determined that there is an abnormality, and the image formation control unit 106d is notified of the occurrence of abnormal noise together with the information of the corresponding unit.

<Image inspection department>
Next, the image inspection unit 106c will be described with reference to FIG. 6 which is a block diagram of the configuration thereof.
As shown in the figure, the image inspection unit 106 c includes an image quality inspection unit 106 c (1) that detects an abnormality in image quality and a wrinkle (wrinkle) inspection unit 106 c (2) that detects the presence or absence of wrinkles on the paper surface.
Hereinafter, first, the image inspection unit 106c will be described.

<Detecting abnormal image quality>
The image inspection unit 106c performs an inspection based on the read image obtained by reading the printed image output on paper with the scanner 120.
The image quality inspection unit 106c (1) acquires an image read by the scanner 120 (hereinafter referred to as “inspection image”) and an image obtained by ripping normal print data (hereinafter referred to as “reference image”). To do. In the acquired reference image, the flatness representing the change in the pixel value is analyzed (Note that the flatness is a change in the pixel value such as a pattern or an edge where the change in the pixel value is large; This is the flatness when a region having a small flatness is a region having a high flatness).

  The image quality inspection unit 106c (1) determines an image area for each type of reference image (for example, an image line unit or a non-image line unit) from the flatness of the analysis result, and performs a predetermined inspection for the determined image area. A threshold value (defect determination criterion; a second threshold value described later) is determined. The image quality inspection unit 106c (1) compares the pixel of the reference image in the determined image area with the pixel of the inspection target image at the same position as the determined image area, and determines the corresponding pixel value (image density or image light amount). The difference between the pixel values to represent is detected. The image quality inspection unit 106c (1) determines whether or not the detected difference exceeds the second threshold value, and inspects a defective portion on the printing surface.

FIG. 7 is a flowchart showing the procedure of the image quality inspection process.
As shown in FIG. 7, first, a reference image and an inspection target image are acquired (S101). Next, based on the acquired reference image, an image line portion and a non-image line portion in the print area on the print surface of the printed material are specified (S102).
Next, in step S103, the identified image portion and non-image portion are divided (S103), and defect determination processing is executed for each.

That is, in the defect determination process (S103, image line unit) for the image line unit, the image feature (density or light quantity) between the reference image corresponding to the specified image line unit and the inspection target image at the same position as the specified image line unit is represented. Pixel values (hereinafter the same) are compared (S104), and a difference is detected. Here, it is determined whether or not the detected difference is greater than or equal to a second threshold value (threshold value for inspection corresponding to the image line portion) (S105). As a result, when the difference is equal to or larger than the second threshold (S105, YES), an abnormality (defect portion) of the image line portion in the print area is detected.
In step S105, when the detected difference is less than the second threshold (S105, NO), it is detected that the image line portion in the print area is normal.

Further, in the defect determination processing (S103, non-image portion) for the non-image portion, image features of the reference image corresponding to the specified non-image portion and the inspection target image at the same position as the specified non-image portion are obtained. The difference is detected and the difference is detected (S106). Here, it is determined whether or not the detected difference is greater than or equal to a predetermined threshold (inspection threshold corresponding to the non-image portion; referred to as a third threshold) (S107). As a result, when the difference is equal to or greater than the third threshold (S107, YES), an abnormality (defect portion) in the non-image area in the print area is detected.
In step S107, when the detected difference is less than the third threshold (S107, NO), it is detected that the non-image area in the print area is normal.
When the image quality inspection unit 106c (1) detects an abnormality in the image line portion or the non-image line portion, it determines that an image quality abnormality has occurred, and notifies the image formation control unit 106d of the determination result.

<Detection of wrinkles>
The wrinkle inspection unit 106c (2) inspects the printed paper for wrinkles based on the read image read by the scanner 120. Actually, the wrinkle inspection unit 106 c (2) acquires a read image (hereinafter referred to as “inspection target image”) on the back surface on which nothing is printed.
Here, when there is a wrinkle in the paper output, the image feature of the pixel at the wrinkle location in the inspection target image is different from the image feature at the location without the wrinkle.

Specifically, the density of the wrinkled part is read higher than the part without the wrinkle. Therefore, a threshold value of a predetermined density (referred to as a fourth threshold value) is set, and when the density value of the inspection target image is equal to or higher than the fourth threshold value, it is determined that the pixel is a wrinkle pixel in the inspection target image.
Further, the number of pixels determined to be wrinkled pixels in the inspection target image is counted, and when the counting result is equal to or greater than a predetermined threshold (referred to as a fifth threshold), it is determined that wrinkles are present.

FIG. 8 is a flowchart showing the procedure of the inspection process for the presence or absence of wrinkle pixels.
As shown in FIG. 8, first, when an inspection target image is acquired (S201), the image feature of one pixel in the inspection target image is compared with a fourth threshold value for determining the presence or absence of wrinkles (S202). Here, if the image feature is “density (representing pixel value)”, it is determined whether or not the pixel value (density value) is greater than or equal to a fourth threshold value (S203). If the pixel value is greater than or equal to the fourth threshold (S203, YES), it is determined that the pixel is a wrinkle pixel, and the total number of wrinkle pixels is counted up by one (S204). When the pixel value is less than the fourth threshold value (S203, NO), step S204 is skipped and the process proceeds to step S205.

In step S205, it is determined whether or not the fourth threshold value has been compared for all pixels in the image area to be inspected. When the fourth threshold value comparison has been completed for all pixels (S205, YES), the process proceeds to step S206. To do. If it has not been completed yet (S205, NO), the process returns to step S202, and the next pixel is checked for wrinkles.
In step S206, the total number of wrinkle pixels in the inspection target image is compared with a fifth threshold value for determining the presence or absence of wrinkles (S206). Next, it is determined whether or not the total number is equal to or greater than the fifth threshold (S207). If the total number is equal to or greater than the fifth threshold (S207, YES), an abnormality is detected as a wrinkle in the inspection target image. On the other hand, when the total number is less than the fifth threshold in step S207 (S207, NO), it is determined as normal.
If the wrinkle inspection unit 106c (2) detects an abnormality with wrinkles, the detection result is notified to the image formation control unit 106d.

<Image formation control unit>
The image formation control unit 106d controls driving of the units 201 to 203 based on the abnormality detection results from the abnormal sound detection unit 106b and the image inspection unit 106c.
FIG. 9 is a flowchart showing a processing procedure of the image formation control unit 106d.
During the operation, the image formation control unit 106d always acquires the abnormal sound detection result from the abnormal sound detection unit 106b (S301). When the image formation control unit 106d receives a notification of the occurrence of abnormal noise (S302, YES), the image formation control unit 106d controls the motors 207 to 209 of each unit 201 to 203 so as to reduce the driving speed (S303).

  Next, the image formation control unit 106d acquires notification (determination result) of image inspection (detection of image quality abnormality and detection of wrinkles) from the image inspection unit 106c (S304). If the determination result is a notification of the occurrence of an abnormal image (S305, YES), the driving of each unit 201-203 is immediately stopped and image formation is stopped (S306). On the other hand, if it is not a notice of occurrence of an abnormal image (S305, NO), the drive speeds of the motors 207 to 209 of the units 201 to 203 are restored (S307) and image formation is continued.

  According to the first embodiment, the drive speeds of the motors 207 to 209 of the units 201 to 203 are decelerated at the stage when the notification of abnormal noise occurrence is acquired. Therefore, during high-speed printing, each unit 201 to 203 is earlier than the case where the motors 207 to 209 of each unit 201 to 203 are stopped from high-speed driving after the image inspection result (abnormal image occurrence) is output. The driving can be stopped. Thereby, the number of unnecessary paper outputs can be suppressed.

Second Embodiment In the first embodiment, on the condition that an abnormality is detected by the abnormal sound detection unit 106b, the driving of each unit 201 to 203 is immediately stopped by the determination result (abnormal image occurrence) of the image inspection unit 106c. . On the other hand, in the second embodiment, when the abnormal sound is detected by the abnormal sound detection unit 106b, a process of switching the inspection unit in the image inspection unit 106c is performed according to the units 201 to 203 in which the abnormal sound is detected.

  In the first embodiment, two abnormal images are detected (image quality abnormality detection and wrinkle presence / absence detection) in the image inspection unit 106c. On the other hand, in the second embodiment, the detection processing amount of the abnormal image is reduced by executing only one detection corresponding to the unit abnormality detected by the abnormal sound detection unit 106b.

A processing procedure in the image inspection unit 106c, which is a part different from the first embodiment, will be described with reference to the flowchart of FIG.
First, the image inspection unit 106c acquires the abnormal sound detection result in the abnormal sound detection unit 106b (S401). The abnormal sound detection result includes information on the abnormal sound generation source unit.
Here, when an abnormal noise has occurred (S402, YES), an image inspection process corresponding to the abnormal noise generating unit is executed based on the unit information on which the abnormal noise has occurred (S403). When this image inspection process is executed, the inspection result is notified to the image formation control unit 106d (S404).

In the image inspection process corresponding to the abnormal sound generation unit in step S403, for example, when abnormal sound is generated in the paper transport unit 201, there is a possibility that the print paper may be wrinkled. Therefore, the wrinkle inspection unit 106c (2) Is to execute the process. Further, when abnormal noise occurs in the developing unit 202, there is a possibility that the image quality of the printing surface may be abnormal, and therefore the processing of the image quality inspection unit 106c (1) is executed.
In these image inspection processes, each threshold value used in the wrinkle inspection unit 106c (2) or the image quality inspection unit 106c (1) may be changed to a threshold value that can easily detect an abnormality.
As described above, in the second embodiment, since an appropriate image inspection unit is selected according to the abnormal sound detection result in the abnormal sound generation source unit, it is limited to units that are considered to be abnormal. By performing a process suitable for it, it is possible to eliminate the waste of the process.

Third Embodiment In the first embodiment, image formation is stopped on condition that both abnormal noise generation in the abnormal noise detection unit 106b and abnormal image generation in the image inspection unit 106c are notified to the image formation control unit 106d. To do.
In contrast, in the present embodiment, image formation is stopped only when an abnormal image caused by the abnormal sound generation source unit detected by the abnormal sound detection unit 106b is detected by the image inspection unit 106c. In other cases, whether or not to stop image formation is displayed on the display device 102, and the user determines whether or not to stop image formation.
According to the present embodiment, the image formation can be reliably stopped only when an abnormal image due to the abnormal sound generation unit is detected, and in other cases, the image formation can be continued at the user's judgment. Therefore, the image formation is not stopped in a delusion.

Next, processing of the image formation control unit 106d in the present embodiment that is different from that of the first embodiment will be described with reference to FIG.
FIG. 11 is a flowchart illustrating a processing procedure of the image formation control unit 106d according to the third embodiment.
During the operation, the image formation control unit 106d always acquires the abnormal sound detection result from the abnormal sound detection unit 106b (S501). Here, when the notification of occurrence of abnormal noise is acquired (S502, YES), the image formation control unit 106d performs control so as to reduce the motor driving speed of the motors 207 to 209 of the units 201 to 203 (S503).

Next, when the image formation control unit 106d receives a notification of an abnormal image from the image inspection unit 106c (S504), the image formation control unit 106d determines whether or not an abnormal image due to a unit that has detected abnormal noise has occurred (S505). Here, when it is determined that an abnormal image due to an abnormal sound detected unit has occurred (S505, YES), driving of each of the units 201 to 203 is stopped and image formation is stopped (S506).
On the other hand, when the image formation control unit 106d determines that no abnormal image due to the unit that has detected abnormal noise has occurred (S505, NO), the display device 102 displays the occurrence of abnormality (S507), and the user is notified. The user is prompted to select whether to stop image formation (S508).

FIG. 12 shows a display example of occurrence of abnormality displayed on the display device 102. If the user selects to stop image formation (S508, YES), the motors 207 to 209 of the units 201 to 203 are stopped to stop image formation. When the stop of image formation is not selected (S508, NO), the driving speed of the motors 207 to 209 is returned to the original (S509), this process is terminated, and the image formation is continued.
According to this embodiment, image formation can be stopped only when abnormality determination with higher accuracy is performed.

Fourth Embodiment Next, an image reading method and a wrinkle detection algorithm performed by the wrinkle inspection unit 106c (2) in the scanner 120 and the image inspection unit 106c for wrinkle detection according to the fourth embodiment will be described. .

FIG. 13 is a diagram showing a configuration of a scanner 120 that reads an image to check whether or not wrinkles are generated in a print output. FIG. 13A is a configuration diagram, FIG. 13B is a plan view, and FIG. 13C is a side view. is there.
In the image forming apparatus according to the present embodiment, the scanner 120 scans a plurality of images simultaneously while adjusting the illuminance of the lamp of the scanner 120 in the line direction and the illuminance control means 120 (1) that arbitrarily adjusts the illuminance of the lamp. An image acquisition unit 120 (2) that acquires each image, and a scan image combination unit 120 (3) that combines the acquired image for each line with a plurality of image data images for each illumination condition, in this case, the scan image 1 and the scan image 2. ). Here, the wrinkle inspection unit 106c (2) inspects the occurrence of wrinkles in the print output by calculating the difference in pixel values (illuminance) between the combined images.

  The lamp 120a of the image inspection scanner 120 does not uniformly irradiate the entire surface of the document 120b placed on the contact glass 120d. That is, the lamp 120a is controlled by the illuminance control means 120 (1), and first irradiates light so that it gradually becomes darker from the left end (FIG. 13B) of the document 120b toward the right end. Next, the lamp 120a irradiates light so that it gradually becomes darker from the right end to the left end of the document 120b. These two irradiation methods are repeated, and the image of the document 120b is captured by the image acquisition unit 120 (2) provided with the image sensor 120c, and two images having different lamp light irradiation methods are obtained.

  FIG. 14 is a diagram schematically showing two images of the document 120b captured by the irradiation method of the lamp 120a shown in FIG. 14A is a side view of the scanner 120, FIG. 14B is a scanned image, and the left side is a scanned image (scanned image 1) when the lamp light of the lamp 120a is irradiated so as to gradually darken from the left side. It is. The right side is a scanned image (scanned image 2) when the lamp light of the lamp 120a is irradiated so as to gradually darken from the right side. In FIG. 14C, the upper row is the scanned image 1 and the lower row is the scanned image 2.

  When wrinkles are generated in the print output, the light from the lamp 120a hits the unevenness at the wrinkle generation location, and a strong shadow appears in the recess. Therefore, between the scan image 1 irradiated with light so that it gradually becomes dark from the left end toward the right end, and the scan image 2 irradiated with light so that it gradually becomes dark from the right end toward the left end. There is a large difference in the luminance value (pixel value) of the wrinkle generating part.

On the other hand, in a normal image such as a character / line image, a large luminance difference does not occur between the scanned image 1 and the scanned image 2. The wrinkle inspection unit 106c (2) (FIG. 6) detects the occurrence of wrinkles by extracting the luminance difference.
Next, an example of a calculation procedure for detecting the presence or absence of wrinkles from the acquired scan image 1 and scan image 2 is shown.

Image1 = Scanned image 1 (RGB 3-channel data)
Image2 = Scanned image 2 (RGB 3-channel data)
image1 (G) = G channel of image1 only
image2 (G) = G channel of image2 only
// Calculate the absolute value of the difference between scanned image 1 and scanned image 2
dif_1_2 = abs (image1 (G)-image2 (G));
dif_2_1 = abs (image2 (G)-image1 (G));
//Binarization
th = threshold
if dif_1_2>th;
bin_1_2 = 1;
else
bin_1_2 = 0;
end
if dif_2_1>th;
bin_2_1 = 1;
else
bin_2_1 = 0;
end
result = abs (bin_1_2-bin_2_1);
The place where result is 1 is determined to be a wrinkle generating part.
According to the present embodiment, “the difference between a plurality of images with different illumination light hits is calculated to emphasize the unevenness of the printed sheet, and is confused with print content such as characters and line drawings printed on the sheet. It is possible to detect the presence or absence of wrinkles without having to do so. ”

Fifth Embodiment In the fifth embodiment, an image reading method performed for wrinkle detection, particularly a lamp light irradiation method, is an embodiment different from the fourth embodiment.
FIG. 15 is a diagram illustrating a configuration of a scanner 120 that reads an image in order to check whether or not wrinkles are generated in a print output. 15A is a plan view of the scanner 120, and FIG. 15B is a side view seen from the direction of the arrow SV in FIG. 15A.

As shown in FIGS. 15A and 15B, the lamp 120a is arranged so as to sandwich the left and right ends (upper and lower ends in FIG. 15A) of the document 120b. The lamp 120a of the scanner 120 for image inspection does not uniformly irradiate the entire surface of the document 120b. In other words, the illuminance control means 120 (1) controls the irradiation method (lighting method) of the lamp 120a symmetrically in the first and second scans on the same document. First, in FIG. 15B, light is irradiated from the left side of the document 120b, and then light is irradiated from the right side of the document 120b. By repeating these two irradiation methods and capturing an image with the image sensor 120c, two images with different lamp light irradiation methods are obtained.
Detection of the occurrence of wrinkles is performed from the two images of the scan image 1 and the scan image 2 by the same method as in the fourth embodiment.

Sixth Embodiment The sixth embodiment is an image reading method for wrinkle detection by a reading method using a document feeder.
FIG. 16 is a diagram illustrating a configuration of a scanner that reads an image in order to check whether or not wrinkles are generated in a print output. 16A is a plan view of the scanner 120, FIG. 16B is a side view seen from the perspective SV1 in FIG. 16A, and FIG. 16C is a side view seen from the perspective SV2 in FIG. 16A.

  A document feeder for image inspection is a known one that feeds print output images one by one. The lamp 120a of the scanner 120 for image inspection does not irradiate light uniformly on the entire surface of the document 120b, but the illuminance control means 120 (1) symmetrically divides the lamp 120a in a time-sharing manner. Control. That is, first, light is emitted so that it gradually becomes darker from the left end portion to the right end portion of the document 120b, and then light is emitted so that it gradually becomes darker from the right end portion of the document toward the left end portion. These two irradiation methods are repeatedly executed, and images are captured by the image sensor 120c, thereby obtaining two images (scan image 1 and scan image 2 similar to FIG. 14B) having different lamp light irradiation methods.

The method for detecting the presence or absence of wrinkles from the two images of the scan image 1 and the scan image 2 is the same as the method shown in the fourth embodiment described with reference to FIGS. Omitted.
According to the present embodiment, there is an effect that two images with different illumination methods necessary for detecting unevenness on a paper surface can be simultaneously acquired by one original surface scan with the same scanner.
In each of the above embodiments, by providing a means for adjusting the illumination angle of the lamp 120a, an effect that the user can adjust the depth of the unevenness of the detected paper surface is obtained.

  The embodiments of the present invention have been described above. However, according to these embodiments, when abnormal noise occurs in the apparatus as in the past, the image forming apparatus is not stopped uniformly, but abnormal noise is generated. If there is no effect on the image formation by determining whether there is an influence on the location and the image formation, the image formation is continued as it is. Can be greatly reduced. Therefore, the situation in which the device becomes unavailable for a long time when abnormal noise occurs can be greatly reduced compared to the conventional case.

Specifically, the image formation by the image forming apparatus is continued when the abnormal sound has no trouble in paper output, and the image formation is continued even when it is determined that the paper output is not wrinkled. Thus, it is possible to prevent a situation in which each of them cannot be used for a long time.
In addition, when abnormal noise is detected, the image formation speed is reduced to stop the image formation immediately if there is a defect in the paper output, thereby preventing the generation of many unnecessary prints. can do.
An appropriate image inspection means can be selected according to the abnormal sound detection result, and the abnormality can be determined more strictly for the unit in which the abnormal sound occurs.
Further, when the image formation control unit 106d determines that an abnormal image due to the unit that has detected abnormal noise has not occurred, the image formation control unit 106d does not automatically stop image formation but determines whether the user continues printing or stops printing. By making the selection possible, it is possible to prevent the image formation from being stopped when the abnormality detection is erroneously determined.

  DESCRIPTION OF SYMBOLS 100 ... Image forming apparatus, 101 ... Input device, 102 ... Display device, 103 ... ROM, 104 ... RAM, 105 ... HDD, 106 ... CPU, 106a ... Operation sound acquisition unit, 106a (1) ... acquisition control unit, 106a (2) ... input / output interface, 106b ... abnormal sound detection unit, 106b (1) ... abnormality determination unit, 106b (2 ) ... spectrum analyzer, 106c ... image inspection unit, 106c (1) ... image quality inspection unit, 106c (2) ... wrinkle inspection unit, 106d ... image formation control unit, 107 ... Interface device 201-203... Unit 204-206 microphone 207-209 motor 120 scanner

JP 2010-54558 A

Claims (10)

An image forming apparatus having an operation sound acquisition unit that acquires operation sounds of each of one or more units in the apparatus,
An abnormal sound detection unit that determines whether the operation sound of each of the units in the apparatus acquired by the operation sound acquisition unit is an abnormal sound,
A scanner unit for reading a printed matter formed by the image forming apparatus;
An image inspection unit that determines the presence or absence of defects in print quality from the read image of the printed matter;
An image formation control unit that performs continuation control or non-continuation control of image formation based on the determination result in the image inspection unit on the condition that the abnormal sound detection unit determines that the noise is abnormal,
An image forming apparatus comprising: The image forming apparatus according to claim 1,
The image formation control unit stops image formation on condition that the abnormal sound detection unit determines that there is abnormal noise and the image inspection unit determines that there is a defect in print quality. Forming equipment. The image forming apparatus according to claim 1 or 2,
The image forming apparatus, wherein the image inspection unit includes an image quality inspection unit that inspects the image quality of a printed image. The image forming apparatus according to claim 1 or 2,
The image forming apparatus, wherein the image inspection unit includes a wrinkle inspection unit that determines a wrinkle in a printed matter as a print quality defect. The image forming apparatus according to claim 1, wherein:
The image forming apparatus, wherein the image forming control unit forms an image at a reduced image forming speed on condition that the abnormal sound detecting unit determines that the abnormal sound is detected. The image forming apparatus according to claim 1,
The image inspection unit has a plurality of inspection means,
The image inspection unit switches inspection means of the image inspection unit based on information indicating an abnormal sound generation unit on the condition that the abnormal sound detection unit determines that the abnormal sound has occurred. Image forming apparatus. The image forming apparatus according to claim 1,
In a state where the abnormal sound detection unit has detected an abnormality, the image inspection unit includes selection means for selecting whether to continue or stop printing on the condition that the image inspection unit has determined that there is no defect in print quality. An image forming apparatus. The image forming apparatus according to claim 4.
Illuminance control means for arbitrarily switching the illuminance of the lamp of the scanner unit in the line direction;
Image acquisition means for acquiring a plurality of images for each scan line simultaneously while adjusting the illuminance of the lamp;
Image synthesizing means for synthesizing the acquired image for each line as a plurality of image data for each illumination condition;
The image forming apparatus, wherein the wrinkle inspection unit inspects the occurrence of wrinkles in a print output by calculating a difference in pixel values between synthesized images. The image forming apparatus according to claim 8.
An image forming apparatus comprising: means for alternately lighting left and right lamps of the scanner unit. The image forming apparatus according to claim 8 or 9,
An image forming apparatus comprising: means for controlling the lamp irradiation method (how to shine) in a left-right symmetric manner or a left-right symmetric manner in a time division in a first scan and a second scan of the same document.

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