Abstract: An image forming apparatus includes an apparatus body, a toner cartridge, a replaceable part, an apparatus body memory, and a controller. The replaceable part includes a replaceable part memory storing therein extended-use allowance-and-restriction information. The extended-use allowance-and-restriction information indicates one of allowance information and restriction information. The extended use is defined as use of the replaceable part even after the replaceable part exceeds the remaining life indicated by the life information stored in the apparatus body memory. The apparatus body memory stores life information indicating remaining life of the replaceable part. In a case where the controller determines that the extended-use allowance-and-restriction information indicates the restriction information, the controller is configured to restrict the extended use of the replaceable part.

Abstract: An image forming apparatus includes a drum cartridge and a controller. The drum cartridge includes a photosensitive drum, a charger and a drum cartridge memory storing a life count value and discharge history information. The controller includes a voltage applying circuit, and an abnormal discharge detection circuit. In a case where the abnormal discharge detection circuit detects an abnormal discharge, the controller does not permit printing in a case where the life count value is equal to or more than a first reference value and a number of abnormal discharges which is included in the discharge history information read from the drum cartridge memory is equal to or more than a particular threshold value, or permits printing in a case where the life count value is equal to or more than the first reference value and the number of abnormal discharges is less than the particular threshold value.

Abstract: An image forming apparatus includes an apparatus body, a toner cartridge, a replaceable part, a controller and an apparatus body memory. An operating mode of the controller is set to one of a subscription mode and a normal mode. The controller is configured to perform processes in accordance with the set operating mode. The apparatus body memory is configured to store life information indicating a remaining life of the replaceable part attached to the apparatus body. The controller is configured to switch a control between: a control for allowing an extended use of the replaceable part; and a control for restricting the extended use of the replaceable part, according to the set operating mode. The extended use is defined as use of the replaceable part even after the replaceable part exceeds the remaining life indicated by the life information stored in the apparatus body memory.

Abstract: An image forming apparatus includes: a photosensitive drum; a developing roller; a separation mechanism configured to switch a state of the photosensitive drum and the developing roller between a contact state and a separation state; a main memory storing therein a first rotation number and a second rotation number; and a controller configured to perform calculating a deterioration quantity of the photosensitive drum based on the first rotation number and the second rotation number in the main memory. A surface of the developing roller contacts a surface of the photosensitive drum in the contact state, whereas the surface of the developing roller is separated from the surface of the photosensitive drum in the separation state. The first rotation number is the number of rotations of the photosensitive drum in the contact state, and the second rotation number is the number of rotations of the photosensitive drum in the separation state.

Abstract: An image forming apparatus includes a photosensitive drum, a transfer unit, a voltage supply circuit, and a controller. The transfer unit is configured to transfer developer onto a printing medium from the photosensitive drum. The voltage supply circuit is configured to supply voltage to the transfer unit. The controller is electrically connected to the voltage supply circuit. The controller is configured to: calculate a cumulative voltage value, the cumulative voltage value being a total of supplied voltage to the transfer unit from the voltage supply circuit after using the transfer unit is started; and determine how long a lifetime of the transfer unit remains based on the calculated cumulative voltage value.

Abstract: An image forming apparatus includes an apparatus body, a toner cartridge, a replaceable part, an apparatus body memory, and a controller. The replaceable part includes a replaceable part memory storing therein extended-use allowance-and-restriction information. The extended-use allowance-and-restriction information indicates one of allowance information and restriction information. The extended use is defined as use of the replaceable part even after the replaceable part exceeds the remaining life indicated by the life information stored in the apparatus body memory. The apparatus body memory stores life information indicating remaining life of the replaceable part. In a case where the controller determines that the extended-use allowance-and-restriction information indicates the restriction information, the controller is configured to restrict the extended use of the replaceable part.

Abstract: A controller is configured to: when an inter-sheet time is shorter than or equal to a first time, maintain a developing roller in contact with a photosensitive drum during an inter-sheet time; when the inter-sheet time is longer than the first time and shorter than or equal to a second time longer than the first time, perform, during the inter-sheet time, at least part of temporary separation processing of temporarily separating the developing roller from the photosensitive drum in a state where the photosensitive drum is rotating; and when the inter-sheet time is longer than the second time, perform, during the inter-sheet time, at least part of temporary stop processing of separating the developing roller from the photosensitive drum and then stopping rotation of the photosensitive drum, and subsequently restarting rotation thereof and then bringing the developing roller into contact with the photosensitive drum.

Abstract: An image forming apparatus includes an apparatus body, a toner cartridge, a replaceable part, an apparatus body memory, and a controller. The replaceable part includes a replaceable part memory storing therein extended-use allowance-and-restriction information. The extended-use allowance-and-restriction information indicates one of allowance information and restriction information. The extended use is defined as use of the replaceable part even after the replaceable part exceeds the remaining life indicated by the life information stored in the apparatus body memory. The apparatus body memory stores life information indicating remaining life of the replaceable part. In a case where the controller determines that the extended-use allowance-and-restriction information indicates the restriction information, the controller is configured to restrict the extended use of the replaceable part.

Abstract: An image forming apparatus includes an apparatus body, a toner cartridge, a replaceable part, a controller and an apparatus body memory. An operating mode of the controller is set to one of a subscription mode and a normal mode. The controller is configured to perform processes in accordance with the set operating mode. The apparatus body memory is configured to store life information indicating a remaining life of the replaceable part attached to the apparatus body. The controller is configured to switch a control between: a control for allowing an extended use of the replaceable part; and a control for restricting the extended use of the replaceable part, according to the set operating mode. The extended use is defined as use of the replaceable part even after the replaceable part exceeds the remaining life indicated by the life information stored in the apparatus body memory.

Abstract: An image forming apparatus includes: a photosensitive drum; a developing roller; a separation mechanism configured to switch a state of the photosensitive drum and the developing roller between a contact state and a separation state; a main memory storing therein a first rotation number and a second rotation number; and a controller configured to perform calculating a deterioration quantity of the photosensitive drum based on the first rotation number and the second rotation number in the main memory. A surface of the developing roller contacts a surface of the photosensitive drum in the contact state, whereas the surface of the developing roller is separated from the surface of the photosensitive drum in the separation state. The first rotation number is the number of rotations of the photosensitive drum in the contact state, and the second rotation number is the number of rotations of the photosensitive drum in the separation state.

Abstract: An image forming apparatus includes an apparatus body, a toner cartridge, a replaceable part, a controller and an apparatus body memory. An operating mode of the controller is set to one of a subscription mode and a normal mode. The controller is configured to perform processes in accordance with the set operating mode. The apparatus body memory is configured to store life information indicating a remaining life of the replaceable part attached to the apparatus body. The controller is configured to switch a control between: a control for allowing an extended use of the replaceable part; and a control for restricting the extended use of the replaceable part, according to the set operating mode. The extended use is defined as use of the replaceable part even after the replaceable part exceeds the remaining life indicated by the life information stored in the apparatus body memory.

Abstract: An image forming apparatus includes a photosensitive drum, a transfer unit, a voltage supply circuit, and a controller. The transfer unit is configured to transfer developer onto a printing medium from the photosensitive drum. The voltage supply circuit is configured to supply voltage to the transfer unit. The controller is electrically connected to the voltage supply circuit. The controller is configured to: calculate a cumulative voltage value, the cumulative voltage value being a total of supplied voltage to the transfer unit from the voltage supply circuit after using the transfer unit is started; and determine how long a lifetime of the transfer unit remains based on the calculated cumulative voltage value.

Abstract: An image forming apparatus includes a drum cartridge and a controller. The drum cartridge includes a photosensitive drum, a charger and a drum cartridge memory storing a life count value and discharge history information. The controller includes a voltage applying circuit, and an abnormal discharge detection circuit. In a case where the abnormal discharge detection circuit detects an abnormal discharge, the controller does not permit printing in a case where the life count value is equal to or more than a first reference value and a number of abnormal discharges which is included in the discharge history information read from the drum cartridge memory is equal to or more than a particular threshold value, or permits printing in a case where the life count value is equal to or more than the first reference value and the number of abnormal discharges is less than the particular threshold value.

Abstract: A controller is configured to: when an inter-sheet time is shorter than or equal to a first time, maintain a developing roller in contact with a photosensitive drum during an inter-sheet time; when the inter-sheet time is longer than the first time and shorter than or equal to a second time longer than the first time, perform, during the inter-sheet time, at least part of temporary separation processing of temporarily separating the developing roller from the photosensitive drum in a state where the photosensitive drum is rotating; and when the inter-sheet time is longer than the second time, perform, during the inter-sheet time, at least part of temporary stop processing of separating the developing roller from the photosensitive drum and then stopping rotation of the photosensitive drum, and subsequently restarting rotation thereof and then bringing the developing roller into contact with the photosensitive drum.

Abstract: An image forming apparatus includes a drum cartridge and a controller. The drum cartridge includes a photosensitive drum, a charger and a drum cartridge memory storing a life count value and discharge history information. The controller includes a voltage applying circuit, and an abnormal discharge detection circuit. In a case where the abnormal discharge detection circuit detects an abnormal discharge, the controller does not permit printing in a case where the life count value is equal to or more than a first reference value and a number of abnormal discharges which is included in the discharge history information read from the drum cartridge memory is equal to or more than a particular threshold value, or permits printing in a case where the life count value is equal to or more than the first reference value and the number of abnormal discharges is less than the particular threshold value.

Abstract: An image forming apparatus includes an apparatus body, a toner cartridge, a replaceable part, a controller and an apparatus body memory. An operating mode of the controller is set to one of a subscription mode and a normal mode. The controller is configured to perform processes in accordance with the set operating mode. The apparatus body memory is configured to store life information indicating a remaining life of the replaceable part attached to the apparatus body. The controller is configured to switch a control between: a control for allowing an extended use of the replaceable part; and a control for restricting the extended use of the replaceable part, according to the set operating mode. The extended use is defined as use of the replaceable part even after the replaceable part exceeds the remaining life indicated by the life information stored in the apparatus body memory.

Abstract: An image forming apparatus includes an apparatus body, a toner cartridge, a replaceable part, an apparatus body memory, and a controller. The replaceable part includes a replaceable part memory storing therein extended-use allowance-and-restriction information. The extended-use allowance-and-restriction information indicates one of allowance information and restriction information. The extended use is defined as use of the replaceable part even after the replaceable part exceeds the remaining life indicated by the life information stored in the apparatus body memory. The apparatus body memory stores life information indicating remaining life of the replaceable part. In a case where the controller determines that the extended-use allowance-and-restriction information indicates the restriction information, the controller is configured to restrict the extended use of the replaceable part.

Abstract: An image forming apparatus includes a drum cartridge and a controller. The drum cartridge includes a photosensitive drum, a charger and a drum cartridge memory storing a life count value and discharge history information. The controller includes a voltage applying circuit, and an abnormal discharge detection circuit. In a case where the abnormal discharge detection circuit detects an abnormal discharge, the controller does not permit printing in a case where the life count value is equal to or more than a first reference value and a number of abnormal discharges which is included in the discharge history information read from the drum cartridge memory is equal to or more than a particular threshold value, or permits printing in a case where the life count value is equal to or more than the first reference value and the number of abnormal discharges is less than the particular threshold value.

Abstract: An image forming apparatus executes reverse charging, toner-supply suspension, second exposure, and second charging, while a photosensitive member rotates at least a full turn. In the reverse charging, a charger charges a portion of a circumferential surface of the photosensitive member to a specified polarity. In the toner-supply suspension, before the portion, which has been charged to the second polarity in the reverse charging, of the circumferential surface of the photosensitive member passes a position at which the developer from the developing unit is configured to initially adhered to the circumferential surface, a developing unit stops supplying developer to the circumferential surface. In the second exposure, an exposure device exposes the portion, which has been charged to the specified polarity in the reverse charging, of the circumferential surface. In the second charging the charger charges the portion, which has been exposed in the second exposure, of the circumferential surface.

Abstract: An image forming apparatus executes charging, exposure, toner-supply suspension, and electric-field generation while a photosensitive member rotates at least a full turn. In the charging, a charger charges a portion of a circumferential surface of the photosensitive member. In the exposure, an exposure device exposes the portion, which has been charged in the charging, of the circumferential surface. In the toner-supply suspension, before the portion, which has been exposed in the exposure, of the circumferential surface passes a position at which developer from a developing unit is configured to initially adhere to the circumferential surface, a developing unit stops supplying developer to the photosensitive member. In the electric-field generation, an electric field is generated in a portion of the photosensitive layer of the photosensitive member corresponding to the portion, which has been exposed by the exposure device, of the circumferential surface.