Abstract: An image forming apparatus includes an image forming device for forming a pattern image having unit images on a photosensitive member, a sensor for irradiating the pattern image with light and detecting reflected light, and a controller for controlling the image forming device to form a pattern image for printing used when printing and a pattern image for detection to be detected by the sensor on the photosensitive member. A first pattern image for printing includes a predetermined number of first unit images arranged with being spaced from each other, each of the first unit images being smaller than a predetermined size. A first pattern image for detection corresponding to the first pattern image for printing includes more than the predetermined number of the first unit images arranged with being spaced from each other.

Abstract: An image forming apparatus includes a belt, a plurality of image forming devices including a photosensitive member, a developing device, a transfer device and a blade, and a control device configured to form a pattern image on a first photosensitive member, when an image to be printed on a sheet is not formed, by applying a developing voltage to a first developing device, an absolute value thereof is greater than that when an image to be printed on a sheet is formed, transfer the pattern image onto the belt and apply a transfer voltage or transfer current having the same polarity as that applied to a second transfer device when an image to be printed on a sheet is formed to the second transfer device when the pattern image to be conveyed by the belt passes the second transfer device.

Abstract: Image forming apparatus includes: main body casing having first and second side walls opposite to each other, and upper portion having opening; top cover swingably supported on the upper portion of the main body casing at a position near the second side wall and configured to openably close the opening; endless belt disposed below the top cover and having first end portion closer to the first side wall and second end portion closer to the second side wall; photoconductor drum disposed under the endless belt; development unit disposed under the photoconductor drum and configured to supply developer to the photoconductor drum; and fixing device disposed above the second end portion of the endless belt. The endless belt is configured to be swingable about axis of rotation provided near the second side wall such that the first end portion of the endless belt is swingable in an upper-lower direction.

Abstract: An image forming apparatus including a controller configured to apply a charging bias to a charger during image formation on a photoconductive body, an absolute value of the charging bias being a first absolute value, apply a development bias to a development roller during the image formation, place the development roller in a development position during the image formation, after the image formation, reduce the absolute value of the charging bias to a second absolute value less than the first absolute value, after reducing the absolute value of the charging bias, separate the development roller away from the photoconductive body and place the development roller in a non-development position, and after placing the development roller in the non-development position, stop applying the development bias to the development roller.

Abstract: An image forming apparatus includes: an image forming unit configured to transfer a developer image; a processor; and memory storing computer readable instructions that, when executed by the processor, causing the image forming apparatus to: perform an image forming operation of forming an image; perform a cleaning operation of cleaning unnecessary developer of the image forming unit; in a case where existence of data of an image which is to be formed is recognized after activation of the image forming apparatus before a first image forming operation, determine whether to perform the cleaning operation; and in a case where existence of data of the image which is to be formed is not recognized after the activation of the image forming apparatus before the first image forming operation, not to perform the cleaning operation.

Abstract: An image forming apparatus includes: a main casing; a photosensitive member; a moving mechanism; a movable member; and a cartridge. The photosensitive member is provided in the main casing. The movable member moves between an inside position in which the movable member is inside the main casing and an outside position in which the movable member is at least partly outside the main casing. The movable member includes: a frame; a protection member; and an exposure member. The protection member is fixed to the frame. The moving mechanism moves the exposure member between an exposing position in which the exposure member exposes the photosensitive member to light and a protected position in which the exposure member is protected by the protection member. The cartridge includes a developer bearing member. The cartridge is supported at the movable member.

Abstract: An image forming apparatus includes a control device executing: a holding process of holding developer attached on an image carrier at a holding member; a moving process of moving the developer from the holding member to the image carrier; and a collection process of collecting the developer attached on the image carrier into a collection member. The control device executes the moving process and the collection process after completing printing. The control device sets a first flag when predetermined time period elapses from start of the moving process and unsets the first flag at start of the printing. When the first flag is not set at a startup time, the control device executes the moving process and the collection process before the printing. When the first flag is set, the control device omits the moving process before the printing.

Abstract: An image forming apparatus includes an image carrier, a cartridge, a collection member for collecting remaining toner which is attached to the image carrier after the toner image has been transferred from the image carrier to a recording medium; and a control device configured to selectively execute a first mode and a second mode. In a case of executing the first mode, the control device controls the collection member to return the remaining toner collected by the collection member to the image carrier with a first frequency. In a case of executing the second mode, the control device controls the collection member to return the remaining toner collected by the collection member to the image carrier with a second frequency that is smaller than the first frequency or to continuously hold the remaining toner collected by the collection member.

Abstract: An image forming apparatus including: an intermediate transfer member configured to transfer the developer images on the plurality of photosensitive members; a secondary transfer member configured to transfer the developer images transferred onto the intermediate transfer member onto a recording sheet; a plurality of primary holding rollers provided to each of the plurality of photosensitive members, respectively; a collecting unit configured to collect developer remaining on the intermediate transfer member; and a control device configured to control biases applied to the secondary transfer member and the plurality of primary holding rollers, wherein, after printing control terminates, the control device is configured to perform cleaning control in which biases having opposite polarities to biases during the printing control are applied to the plurality of primary holding rollers and the secondary transfer member.

Abstract: Image forming apparatus includes: main body casing having first and second side walls opposite to each other, and upper portion having opening; top cover swingably supported on the upper portion of the main body casing at a position near the second side wall and configured to openably close the opening; endless belt disposed below the top cover and having first end portion closer to the first side wall and second end portion closer to the second side wall; photoconductor drum disposed under the endless belt; development unit disposed under the photoconductor drum and configured to supply developer to the photoconductor drum; and fixing device disposed above the second end portion of the endless belt. The endless belt is configured to be swingable about axis of rotation provided near the second side wall such that the first end portion of the endless belt is swingable in an upper-lower direction.

Abstract: An image forming apparatus includes a controller capable of performing a printing control and a cleaning control. In the printing control, developer images carried on the image carriers are transferred toward the opposing surface or a recording sheet by applying a transfer current between each of the image carriers and the transfer device. In the cleaning control, developer collected by the cleaning rollers is transferred toward the image carriers and the transfer device and collected by the cleaning device by applying a transfer current between each of the image carriers and the transfer device and switching an electric field established between the image carrier and the corresponding cleaning roller. The controller is configured to control the transfer current such that an average absolute value of the transfer current in the cleaning control is smaller than that in the printing control.

Abstract: Image forming apparatus includes: main body casing having first and second side walls opposite to each other, and upper portion having opening; top cover swingably supported on the upper portion of the main body casing at a position near the second side wall and configured to openably close the opening; endless belt disposed below the top cover and having first end portion closer to the first side wall and second end portion closer to the second side wall; photoconductor drum disposed under the endless belt; development unit disposed under the photoconductor drum and configured to supply developer to the photoconductor drum; and fixing device disposed above the second end portion of the endless belt. The endless belt is configured to be swingable about axis of rotation provided near the second side wall such that the first end portion of the endless belt is swingable in an upper-lower direction.

Abstract: An image forming apparatus includes an image carrier, a cartridge, a collection member for collecting remaining toner which is attached to the image carrier after the toner image has been transferred from the image carrier to a recording medium; and a control device configured to selectively execute a first mode and a second mode. In a case of executing the first mode, the control device controls the collection member to return the remaining toner collected by the collection member to the image carrier with a first frequency. In a case of executing the second mode, the control device controls the collection member to return the remaining toner collected by the collection member to the image carrier with a second frequency that is smaller than the first frequency or to continuously hold the remaining toner collected by the collection member.

Abstract: There is provided an image processing device which converts multi-gradation pixels configuring a multi-gradation image of image data to be used in a color image forming apparatus, into unit dither patterns. The image forming apparatus includes photosensitive members on which developer images are formed by supplying developer to electrostatic latent images, and an exposure device which exposes the photosensitive members. The developer images on the photosensitive members are transferred to a transferred medium which is moved while contacting the photosensitive members. The image processing device includes a processing unit which converts a multi-gradation pixel of a first color into unit dither patterns, each unit dither pattern consisting of a first line extending in a predetermined direction and a second line extending in a direction intersecting with the first line when a gradation value of the multi-gradation pixel is within a predetermined range.

Abstract: An image forming apparatus includes: a main casing; a photosensitive member; a moving mechanism; a movable member; and a cartridge. The photosensitive member is provided in the main casing. The movable member moves between an inside position in which the movable member is inside the main casing and an outside position in which the movable member is at least partly outside the main casing. The movable member includes: a frame; a protection member; and an exposure member. The protection member is fixed to the frame. The moving mechanism moves the exposure member between an exposing position in which the exposure member exposes the photosensitive drum to light and a protected position in which the exposure member is protected by the protection member. The cartridge includes a developer bearing member. The cartridge is supported at the movable member.

Abstract: There is provided an image forming apparatus including plural photosensitive members on which developer images are formed by supplying developer to electrostatic latent images, respectively, an exposure device which illuminates light beams onto surfaces of the photosensitive members to form the electrostatic latent images, respectively. The developer images on the respective photosensitive numbers are transferred to a transferred medium which is moved in a moving direction while contacting the respective photosensitive members. The exposure device is configured such that a beam diameter of light beam exposing a most-upstream photosensitive member in the moving direction on a surface of the most-upstream photosensitive member is larger than a beam diameter of light beam exposing a most-downstream photosensitive member in the moving direction on a surface of the most-downstream photosensitive member.

Abstract: An image forming apparatus includes: a first photosensitive drum for a monochrome printing mode; second and third photosensitive drums for a color printing mode; a moving unit moving a medium from the first photosensitive drum via the second photosensitive drum to the third photosensitive drum; charger devices for charging the photosensitive drums; transfer devices for transferring developer images on the photosensitive drums to the medium; and a control unit configured to control charging biases of the charger devices and transfer biases of the transfer devices. The control unit executes, in the monochrome printing mode, an energy saving control in which an absolute value of a charging bias applied to the charger device for the third photosensitive drum is smaller than an absolute value of a charging bias applied to the charger device corresponding to the second photosensitive drum.

Abstract: An image forming apparatus including: an intermediate transfer member configured to transfer the developer images on the plurality of photosensitive members; a secondary transfer member configured to transfer the developer images transferred onto the intermediate transfer member onto a recording sheet; a plurality of primary holding rollers provided to each of the plurality of photosensitive members, respectively; a collecting unit configured to collect developer remaining on the intermediate transfer member; and a control device configured to control biases applied to the secondary transfer member and the plurality of primary holding rollers, wherein, after printing control terminates, the control device is configured to perform cleaning control in which biases having opposite polarities to biases during the printing control are applied to the plurality of primary holding rollers and the secondary transfer member.

Abstract: An image forming apparatus includes: an image forming unit configured to transfer a developer image; a processor; and memory storing computer readable instructions that, when executed by the processor, causing the image forming apparatus to: perform an image forming operation of forming an image; perform a cleaning operation of cleaning unnecessary developer of the image forming unit; in a case where existence of data of an image which is to be formed is recognized after activation of the image forming apparatus before a first image forming operation, determine whether to perform the cleaning operation; and in a case where existence of data of the image which is to be formed is not recognized after the activation of the image forming apparatus before the first image forming operation, not to perform the cleaning operation.

Abstract: Image forming apparatus includes: main body casing having first and second side walls opposite to each other, and upper portion having opening; top cover swingably supported on the upper portion of the main body casing at a position near the second side wall and configured to openably close the opening; endless belt disposed below the top cover and having first end portion closer to the first side wall and second end portion closer to the second side wall; photoconductor drum disposed under the endless belt; development unit disposed under the photoconductor drum and configured to supply developer to the photoconductor drum; and fixing device disposed above the second end portion of the endless belt. The endless belt is configured to be swingable about axis of rotation provided near the second side wall such that the first end portion of the endless belt is swingable in an upper-lower direction.