JP2008256959A - Image forming apparatus and control method for image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus, wherein output image has high image quality by obtaining information on paper kind and paper quality, and a control method for the image forming apparatus. <P>SOLUTION: The image forming apparatus is constituted of a paper conveying unit 19, an exposure unit 9 forming an electrostatic latent image by exposing a photoreceptor 23, a developing device 10, an intermediate transfer belt 33, a secondary transfer unit 16, and a fixing unit 63, and has an excess component optical path passing through an image non-forming area other than an image forming area on the photoreceptor 23 out of an optical path from the exposure unit 9, optical path changing means (81, 82 and 83) provided in the excess component optical path, an irradiation means for irradiating paper with light from the optical path changing means, and a reflected light receiving part 91 receiving reflected light from the irradiation means and detecting the intensity of the reflected light. The setting of the paper conveying unit 19 or/and the setting the developing device 10 or/and the setting of the fixing unit 63 are changed in accordance with the intensity of the reflected light detected by the reflected light receiving part 91. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image forming apparatus such as a printer, a copier, a facsimile machine, a multi-function machine, and the like that forms a latent image on a photosensitive member by laser or light emitting element array scanning and develops the latent image. The present invention relates to a method for controlling an image forming apparatus.

  Conventionally, in an image forming apparatus such as a printer, a copier, a facsimile machine, or a multifunction machine, a latent image is formed on a photosensitive member by laser scanning or a light emitting element array, and an image is obtained by developing the latent image. An image forming process is known.

In such an image forming process, if the parameters in the image forming process are changed depending on the paper quality of the paper on which the image is formed and the difference in paper type (whether the paper surface is rough or smooth). Therefore, it is possible to perform ideal image formation according to each paper quality and paper type. Conventionally, various attempts have been made to obtain paper type information before the image forming process. In order to obtain the paper type information, it is conceivable to use an optical detection method. Examples of such a method include, for example, Patent Document 1 (Japanese Patent Laid-Open No. 2000-75562), a light emitting unit, a light receiving unit, A detection unit that irradiates the print medium with light from the light emitting unit and detects the amount of transmitted light by the light receiving unit, and a print medium determination unit that determines the transparency of the print medium based on the output of the detection unit. In the image forming apparatus that performs different print control depending on the transparency of the print medium, the image forming apparatus is characterized in that the detection unit has a plurality of switchable sensitivities.
JP 2000-75562 A

  According to the configuration disclosed in Patent Document 1, it is necessary to provide a dedicated light emitting unit for obtaining paper type information, and there is a problem that the configuration becomes complicated.

  In order to solve the above problems, an image forming apparatus according to the present invention includes a sheet conveying unit that conveys a sheet, a photoconductor, and an exposure unit that exposes the photoconductor to form an electrostatic latent image. Developing means for developing the electrostatic latent image formed on the photosensitive member with toner, an intermediate transfer member for transferring the developed image developed on the photosensitive member, and transferring the developed image on the intermediate transfer member to a sheet A transfer unit that fuses the toner image on the paper transferred by the transfer unit to form a permanent visible image, an exposure light source provided in the exposure unit, and an optical path from the exposure light source A margin spectral path passing through a non-image forming area outside the image forming area on the photoconductor, an optical path changing means provided in the margin spectral path, an irradiating means for irradiating the paper with light from the optical path changing means, and A light receiving means for receiving reflected light from the irradiation means and detecting the intensity of the reflected light; It has, according to the intensity of the detected reflected light at the light receiving unit, and changes the setting of the setting and / or fixing means setting and / or the developing means the paper conveying means.

  The image forming apparatus of the present invention also includes a sheet conveying unit that conveys a sheet, a photoconductor, an exposure unit that exposes the photoconductor to form an electrostatic latent image, and an electrostatic image formed on the photoconductor. A developing means for developing the latent image with toner, a transferring means for transferring the developed image developed on the photosensitive member to the paper, and a toner image on the paper transferred by the transferring means are fused to make it permanently visible. A fixing unit for forming an image, an exposure light source provided in the exposure unit, a margin spectral path passing through a non-image forming region outside the image forming region on the photosensitive member in an optical path from the exposure light source, and in the margin spectral path An optical path changing means provided in the optical path, an irradiating means for irradiating the paper with light from the optical path changing means, and a light receiving means for receiving the reflected light from the irradiating means and detecting the intensity of the reflected light, According to the intensity of the reflected light detected by the light receiving means, the paper conveying means And changes a setting or / and setting and / or setting of the fixing means of the developing unit.

  Further, the image forming apparatus of the present invention is characterized in that the setting of the sheet conveying speed in the sheet conveying unit is changed.

  The image forming apparatus of the present invention is characterized in that the setting of the bias voltage in the developing means is changed.

  The image forming apparatus of the present invention is characterized in that the setting of the fixing temperature in the fixing unit is changed.

  In the image forming apparatus of the present invention, the exposure light source is a laser.

  In the image forming apparatus of the present invention, the exposure light source is an LED.

  In the image forming apparatus of the present invention, the exposure light source is an organic EL element.

  The image forming apparatus control method according to the present invention includes a sheet conveying unit that conveys a sheet, a photosensitive member, an exposure unit that exposes the photosensitive member to form an electrostatic latent image, and a photosensitive member. Developing means for developing the electrostatic latent image with toner, an intermediate transfer member for transferring the developed image developed on the photosensitive member, a transfer means for transferring the developed image on the intermediate transfer member to a sheet, Fixing means for fusing the toner image on the paper transferred by the transfer means to make a permanent visible image, an exposure light source provided in the exposure means, and image formation on the photoreceptor in the optical path from the exposure light source A margin spectral path that passes through a non-image forming area outside the area, an optical path changing means provided in the margin spectral path, an irradiating means for irradiating light from the optical path changing means to the paper, and reflected light from the irradiating means Light receiving means for detecting the intensity of reflected light and detecting the intensity of reflected light A control method of the image forming apparatus for controlling the position of the image forming apparatus, wherein the setting of the sheet conveying unit and / or the setting of the developing unit or / and the fixing unit are set according to the intensity of the reflected light detected by the light receiving unit. It is characterized by changing the setting.

  The image forming apparatus control method according to the present invention includes a sheet conveying unit that conveys a sheet, a photosensitive member, an exposure unit that exposes the photosensitive member to form an electrostatic latent image, and a photosensitive member. A developing unit that develops the electrostatic latent image with toner, a transfer unit that transfers the developed image developed on the photosensitive member to a sheet, and a toner image on the sheet transferred by the transfer unit. A fixing means for forming a permanent visible image; an exposure light source provided in the exposure means; a margin spectral path passing through a non-image forming area outside the image forming area on the photosensitive member of the optical path from the exposure light source; and the margin An optical path changing means provided in the spectroscopic path, an irradiating means for irradiating the paper with the light from the optical path changing means, and a light receiving means for receiving the reflected light from the irradiating means and detecting the intensity of the reflected light. An image forming apparatus control method for controlling an image forming apparatus having: Depending on the intensity of the detected reflected light at the light-receiving unit, and changes the settings and / or set of fixing means setting or / and the developing means the paper conveying means.

  According to the image forming apparatus and the image forming apparatus control method of the present invention as described above, the paper type / paper quality information can be obtained with a simple configuration. Further, according to the image forming apparatus and the control method of the image forming apparatus of the present invention, the obtained paper type / paper quality information can be reflected in the image forming process, so that the image quality can be improved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing an overall configuration of an image forming apparatus taking a tandem type as an example according to an embodiment of the present invention. In FIG. 1, 1 is an image forming apparatus, 9 is an exposure unit, 10 is a developing device, 11 is an image forming unit, 15 is a transfer belt unit, 16 is a secondary transfer unit, 17 is a paper feed unit, and 19 is paper transport. Unit, 21 is a toner cartridge, 21Y is a yellow toner cartridge, 21M is a magenta toner cartridge, 21C is a cyan toner cartridge, 21K is a black toner cartridge, 23 is a photoconductor, 25 is a corona charging means, 27 is a driving roller, and 29 is a driven roller Rollers, 33 an intermediate transfer belt, 39 a secondary transfer roller, 45 a polygon mirror motor, 47 a polygon mirror, 49 a scanner means, 51 an f-θ lens, 53 a reflecting mirror, 57 a paper feed cartridge, 59 Is a pickup roller, 61 is a gate roller pair, 63 is a fixing unit DOO, 65 discharge roller pair 69 is a pair of fixing rollers, 71 denotes an operation display panel, respectively.

  The image forming apparatus 1 includes an exposure unit 9, an image forming unit 11, a transfer belt unit 15, a secondary transfer unit 16, a paper feed unit 17, and a paper transport unit 19 in a housing (not shown).

  The image forming unit 11 includes four toner cartridges 21 in which four developing devices that store different color toners can be set. The four toner cartridges 21 are for yellow, magenta, cyan, and black developing devices, and are denoted by reference numerals 21Y, 21M, 21C, and 21K in the drawing. In each of the toner cartridges 21Y, 21M, 21C, and 21K, a photosensitive member 23, a corona charging unit 25 provided around the photosensitive member 23, and the developing device 10 are disposed.

  The transfer belt unit 15 includes a drive roller 27 that is rotationally driven by a drive source (not shown), a driven roller 29 of the drive roller 27, and an intermediate transfer belt 33 that is stretched between these rollers and driven to circulate. ing.

  The photoconductor 23 is pressed against the surface of the transfer belt unit 15 and is driven to rotate. By providing a tension roller (not shown) and adjusting the position of such a tension roller, the tension, curvature, etc. of the intermediate transfer belt 33 can be controlled.

The drive roller 27 also serves as a backup roller for the secondary transfer roller 39 in the secondary transfer unit 16. Further, on the peripheral surface of the drive roller 27, for example, a rubber layer having a thickness of about 3 mm and a volume resistivity of 10 ⁵ Ω · cm or less is formed, and the secondary transfer roller is grounded through a metal shaft. The secondary transfer bias conductive path supplied via the line 39 is configured.

  A primary transfer member 43 abuts on the back surface of the intermediate transfer belt 33 at a position facing the photoreceptor 23 of each toner cartridge 21Y, 21M, 21C, and 21K, and a transfer bias is applied to the primary transfer member 43. It is like that.

  A bias application unit 75 (not shown) is responsible for setting and adjusting the transfer bias and the applied voltage of the secondary transfer bias.

  Next, the exposure unit 9 will be described with reference to FIG. FIG. 2 is a diagram schematically showing the relationship between the exposure unit and one photoconductor. In FIG. 2, 45 is a polygon mirror motor, 47 is a polygon mirror, 49 is a scanner means, 51 is an f-θ lens, and 53 is a reflection mirror.

  The exposure unit 9 is provided in a space above the image forming unit 11 as shown in FIG. A paper feed unit 17 is provided below the exposure unit 9. The exposure unit 9 is provided with scanner means 49 including a polygon mirror motor 45 and a polygon mirror 47. In addition, a single f-θ lens 51 and a reflection mirror 53 are provided in the optical path so that the scanning light path of each color is irradiated onto the photoconductor 23.

  In the exposure unit 9, an image signal corresponding to each color is emitted from the polygon mirror 47 with a laser beam modulated and formed based on a common data clock frequency, passes through the f-θ lens 51, the reflection mirror 53, and then each toner cartridge. Irradiation onto the photoreceptors 23 of 21Y, 21M, 21C, and 21K forms a latent image.

  The paper feed unit 17 includes a paper feed cartridge 57 on which the paper P is stacked, and a pickup roller 59 that feeds the paper P from the paper feed cartridge 57 one by one. The paper transport unit 19 includes a gate roller pair 61 that defines the timing of feeding the recording medium P to the secondary transfer unit, a secondary transfer roller 39 that is pressed against the drive roller 27 and the intermediate transfer belt 33, and a fixing unit 63. And a paper discharge roller pair 65.

  The fixing unit 63 performs secondary transfer onto a sheet by pressing and urging at least one of a rotatable fixing roller pair 69 containing a heating element such as a halogen heater and at least one roller of the fixing roller pair 69 to the other side. The toner for forming the secondary image that is secondarily transferred to the recording medium such as paper has a predetermined means in the nip portion formed by the fixing roller pair 69. It is fused to the recording medium at a temperature to become a permanent visible image.

  The developing device 10 is of a type that circulates and uses toner, and is set in each toner cartridge 21Y, 21M, 21C, and 21K. The construction of these developing devices is basically the same.

  The operation unit (operation unit) is a part for the user to operate the image forming apparatus 1 and includes an operation display panel 71 and operation buttons. A device such as a touch panel is provided on the operation display panel 71, and the user directly touches the operation display panel 71 while referring to a UI (user interface) displayed on the operation display panel 71. The second operation can be performed. In the operation unit, various setting actions such as setting of printing conditions in the image forming apparatus 1 are possible.

  The paper passing through the paper transport unit 19 is irradiated with light from the exposure unit 9 that is not used for image formation by the optical path changing means. At this time, the reflected light receiving unit 91 receives the reflected light from the paper P and detects the intensity, and the transmitted light receiving unit 92 receives the transmitted light of the irradiated light and detects the intensity.

  Next, surplus light not used for image formation in the exposure unit 9 will be described with reference to FIG. FIG. 3 is a view showing the reflection mirror and the photoreceptor extracted from the image forming apparatus of the present invention. Of the light reflected by the reflecting mirror 53 and applied to the photoconductor 23, the light applied to the image forming area where an image is formed on the photoconductor 23 is the light in the optical paths B to C in the figure. The light in the optical path A to the optical path B and the optical path C to the optical path D becomes a sufficient amount of light that is not used for image formation. In the present invention, such extra light is guided to the paper P and used to detect the paper type and quality of the paper P. For this purpose, an optical path changing means is provided in the spare spectral path. When the laser type exposure unit 9 is used, a paper is used by using an optical path changing unit including a first optical path changing unit 81, a second optical path changing unit 82, a third optical path changing unit 83 and the like as shown in FIG. P is irradiated with light. The wavelength of the laser beam is about 785 nm.

  FIG. 4 is a view showing a configuration for guiding excess light to the paper P when a line head is used as the exposure unit 9. In FIG. 4, 85 is a line head, 86 is a line head surplus light receiving unit, and 87 is an optical fiber. There are margin light emitting portions that are not used for image formation at both ends of the line head 85, and the light from the margin light emitting portions is received by the line head surplus light receiving portion 86, and the optical fiber 87 is used to form the paper P. Irradiate light. As the line head, both an LED and an organic EL element can be used.

  As described above, in the present invention, the paper type / paper quality information is obtained by a simple configuration using the surplus light of the exposure unit 9, and the obtained paper type / paper quality information is reflected in the image forming process. Therefore, the image quality is improved.

  Control of the image forming apparatus configured as described above will be described. FIG. 5 is a diagram showing a block configuration of elements related to control according to the embodiment of the present invention. In FIG. 5, the control unit 100 is a general-purpose information processing mechanism having a CPU, a RAM, and a ROM. The reflected light intensity detected by the reflected light receiving unit 91 and user settings on the operation display panel 71 are input. Each unit is controlled according to the input. The user on the operation display panel 71 is a user's preference for image quality, and the setting parameters of each unit in the image forming process are changed based on the setting.

  The parameters whose settings can be changed during the image forming process in the present invention are the conveyance speed of the conveyance unit 19, the bias voltage of the image forming unit 11 and the secondary transfer unit 16 (depending on the setting of the bias application unit 75), and the fixing unit 63. Although the fixing temperature is used, other parameters can be changed depending on the paper type / paper quality information obtained by reflected light.

FIG. 6 is a diagram showing an outline of the relationship between the reflected light intensity in the reflected light receiving unit 91 and each parameter. In addition, the relationship schematic shown in FIG. 6 is one standard,
FIG. 6A is a diagram showing the relationship between the reflected light intensity in the reflected light receiving unit 91 and the smoothness of the surface of the paper P (the reverse of the surface roughness). The lower the surface roughness, that is, the higher the smoothness, the stronger the intensity of the reflected light of the light irradiated onto the paper P.

  FIG. 6B is a diagram illustrating a relationship between the reflected light intensity in the reflected light receiving unit 91 and the transport speed of the transport unit 19. The higher the surface roughness (the lower the smoothness), the greater the amount of toner adsorbed onto the paper P. The heat capacity for melting the increased amount of toner is gained by the passage time of the fixing unit 63. The passing time of the fixing unit 63 can be determined by the transport speed of the transport unit 19.

  FIG. 6C is a diagram illustrating the relationship between the reflected light intensity in the reflected light receiving unit 91 and the bias voltages of the image forming unit 11 and the secondary transfer unit 16. The higher the smoothness of the paper P, the lower the toner adsorption rate. Therefore, the amount of toner adsorption is increased by increasing the bias voltage accordingly.

  FIG. 6D is a diagram illustrating a relationship between the reflected light intensity in the reflected light receiving unit 91 and the fixing temperature of the fixing unit 63. The higher the surface roughness (the lower the smoothness), the greater the amount of toner adsorbed onto the paper P. The heat capacity for melting the increased amount of toner is provided by the temperature increase of the fixing unit 63.

  Based on the above tendency, the control unit 100 controls the conveyance speed of the conveyance unit 19, the bias voltage of the image forming unit 11 and the secondary transfer unit 16, and the fixing temperature of the fixing unit 63. Note that the control unit 100 may control any one of the conveyance speed, the bias voltage, and the fixing temperature, or may control any combination thereof.

  In the above description of the present embodiment, the conveyance speed of the conveyance unit 19, the bias voltage of the image forming unit 11 and the secondary transfer unit 16, and the fixing unit are determined based on the information related to the light intensity detected by the reflected light receiving unit 91. Although the case where each setting of the fixing temperature 63 is changed has been described, the information from the transmitted light receiving unit 92 may be used for the image forming process.

  In the above description of the present embodiment, the development image on the photosensitive member 23 is temporarily transferred to the intermediate transfer belt 33 and then subjected to secondary transfer by the secondary transfer unit 16. The present invention is not limited to the transfer onto the paper by such a two-time transfer, but can also be applied to an image forming apparatus that transfers directly from the photoreceptor to the paper.

  According to the present invention as described above, the paper type / paper quality information can be obtained with a simple configuration. Further, according to the image forming apparatus and the control method of the image forming apparatus of the present invention, the obtained paper type / paper quality information can be reflected in the image forming process, so that the image quality can be improved.

1 is a cross-sectional view illustrating an overall configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing the relationship between the exposure unit and one photoconductor. FIG. 3 is a view showing a reflection mirror and a photoreceptor extracted from the image forming apparatus according to the present invention. 3 is a view showing a configuration for guiding excess light to a sheet P when a line head is used as the exposure unit 9. FIG. It is a figure which shows the block configuration of the element relevant to the control which concerns on embodiment of this invention. It is a figure which shows the outline of a relationship between the reflected light intensity in the reflected light light-receiving part 91, and each parameter.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus, 9 ... Exposure unit, 10 ... Developing apparatus, 11 ... Image forming unit, 15 ... Transfer belt unit, 16 ... Secondary transfer unit, 17 ... Paper feed unit, 19 ... paper transport unit, 21 ... toner cartridge, 21Y ... yellow toner cartridge, 21M ... magenta toner cartridge, 21C ... cyan toner cartridge, 21K ... black toner Cartridge, 23 ... photosensitive member, 25 ... corona charging means, 27 ... driving roller, 29 ... driven roller, 33 ... intermediate transfer belt, 39 ... secondary transfer roller, 45. ..Polygon mirror motor, 47... Polygon mirror, 49... Scanner means, 51... F-.theta. Lens, 53.・ Feeding cartridge, 59... Pickup roller, 61... Gate roller pair, 63... Fixing unit, 65. Panel, 75... Bias applying unit, 81... First optical path changing unit, 82... Second optical path changing unit, 83... Third optical path changing unit, 85. Line head surplus light receiving part, 87 ... optical fiber, 91 ... reflected light receiving part, 92 ... transmitted light receiving part, 100 ... control part

Claims (10)

Paper transport means for transporting paper,
A photoreceptor,
Exposure means for exposing the photoreceptor to form an electrostatic latent image;
Developing means for developing the electrostatic latent image formed on the photoreceptor with toner;
An intermediate transfer member for transferring a developed image developed on the photosensitive member;
Transfer means for transferring the developed image on the intermediate transfer member to a sheet;
A fixing means for fusing the toner image on the paper transferred by the transfer means into a permanent visible image;
An exposure light source provided in the exposure means;
A margin spectral path that passes through a non-image forming area outside the image forming area on the photoreceptor among the optical path from the exposure light source, and
An optical path changing means provided in the margin spectral path;
Irradiating means for irradiating the paper with light from the optical path changing means;
Light receiving means for receiving reflected light from the irradiation means and detecting the intensity of the reflected light, and
An image forming apparatus comprising: changing the setting of the sheet conveying unit and / or the setting of the developing unit and / or the setting of the fixing unit according to the intensity of the reflected light detected by the light receiving unit. Paper transport means for transporting paper,
A photoreceptor,
Exposure means for exposing the photoreceptor to form an electrostatic latent image;
Developing means for developing the electrostatic latent image formed on the photoreceptor with toner;
Transfer means for transferring a developed image developed on the photoreceptor to a sheet;
Fixing means for fusing the toner image on the paper transferred by the transfer means into a permanent visible image;
An exposure light source provided in the exposure means;
A margin spectral path passing through a non-image forming area outside the image forming area on the photoconductor among the optical path from the exposure light source,
An optical path changing means provided in the margin spectral path;
Irradiating means for irradiating the paper with light from the optical path changing means;
Light receiving means for receiving reflected light from the irradiation means and detecting the intensity of the reflected light, and
An image forming apparatus comprising: changing the setting of the sheet conveying unit and / or the setting of the developing unit and / or the setting of the fixing unit according to the intensity of reflected light detected by the light receiving unit. 3. The image forming apparatus according to claim 1, wherein a setting of a sheet conveying speed in the sheet conveying unit is changed. 4. The image forming apparatus according to claim 1, wherein a bias voltage setting in the developing unit is changed. 5. The image forming apparatus according to claim 1, wherein the fixing temperature setting in the fixing unit is changed. 6. The image forming apparatus according to claim 1, wherein the exposure light source is a laser. The image forming apparatus according to claim 1, wherein the exposure light source is an LED. 6. The image forming apparatus according to claim 1, wherein the exposure light source is an organic EL element. Paper transport means for transporting paper,
A photoreceptor,
Exposure means for exposing the photoreceptor to form an electrostatic latent image;
Developing means for developing the electrostatic latent image formed on the photoreceptor with toner;
An intermediate transfer member for transferring a developed image developed on the photosensitive member;
Transfer means for transferring the developed image on the intermediate transfer member to a sheet;
A fixing means for fusing the toner image on the paper transferred by the transfer means into a permanent visible image;
An exposure light source provided in the exposure means;
A margin spectral path that passes through a non-image forming area outside the image forming area on the photoreceptor among the optical path from the exposure light source, and
An optical path changing means provided in the margin spectral path;
Irradiating means for irradiating the paper with light from the optical path changing means;
A method for controlling the image forming apparatus, comprising: a light receiving unit that receives reflected light from the irradiation unit and detects the intensity of the reflected light;
Control of the image forming apparatus, wherein the setting of the sheet conveying unit and / or the setting of the developing unit or / and the setting of the fixing unit are changed according to the intensity of the reflected light detected by the light receiving unit Method. Paper transport means for transporting paper,
A photoreceptor,
Exposure means for exposing the photoreceptor to form an electrostatic latent image;
Developing means for developing the electrostatic latent image formed on the photoreceptor with toner;
Transfer means for transferring a developed image developed on the photoreceptor to a sheet;
Fixing means for fusing the toner image on the paper transferred by the transfer means into a permanent visible image;
An exposure light source provided in the exposure means;
A margin spectral path passing through a non-image forming area outside the image forming area on the photoconductor among the optical path from the exposure light source,
An optical path changing means provided in the margin spectral path;
Irradiating means for irradiating the paper with light from the optical path changing means;
A method of controlling an image forming apparatus that controls an image forming apparatus having light receiving means for receiving reflected light from the irradiating means and detecting the intensity of the reflected light,
Control of the image forming apparatus, wherein the setting of the sheet conveying unit and / or the setting of the developing unit or / and the setting of the fixing unit are changed according to the intensity of the reflected light detected by the light receiving unit Method.

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