Brother Kogyo Kabushiki-kaisha

Chieko Mimura

Tadao Kyotani

Shota Iriyama

Kengo Yada

Hotaka Kakutani

Hiroshige Hiramatsu

Kazutoshi Kotama

Shintaro Sakaguchi

Yusuke Ikegami

Yuichi Matsushita

Toshiyuki Sano

Junya Sumida

Keita Suzuki

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. In a case where the controller determines that the extended-use allowance-and-restriction information indicates the allowance information, the controller is configured to allow the extended use of the replaceable part.

Image forming apparatus capable of controlling extension of use of drum cartridge

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.

Drum cartridge for use with a toner cartridge in an image forming apparatus

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.

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.

Image forming apparatus capable of calculating deterioration quantity of photosensitive drum based on the number of rotations in contact and separation states

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.

Image forming apparatus including transfer unit and capable of determining lifetime of transfer unit

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.

Image forming apparatus with developing roller separation processing

Image forming apparatus

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.

Charge removal process in image forming apparatus

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.

Apparatus, methods, and computer-readable mediums are described for adjusting a charge voltage for a photosensitive member to account for accumulated charge quantity. In one example, currents related to charging a charger, which imparts a charge to a photosensitive member, are monitored. Based on the monitored currents, a new charging voltage may be determined and applied that accounts for accumulated charge quantity in the photosensitive member. A transfer current related to a transfer charge may also be monitored or a predetermined value used. The determination of the new charging voltage may be performed at various times.

Charge voltage controller for process unit of image forming apparatus, method of controlling the same, and non-transitory computer-readable storage medium

An image forming apparatus configured to, in a case where a difference between a charging current flowing through a first charging roller and a charging current flowing through a second charging roller is larger than a first threshold value, perform first cleaning processing in which a cleaning ability of one cleaner of a first cleaner and a second cleaner, which corresponds to one of the first charging roller and the second charging roller, is lower than a cleaning ability of another cleaner of the first cleaner and the second cleaner, which corresponds to another of the first charging roller and the second charging roller, a charging current flowing through the one charging roller being larger than a charging current flowing through the other charging roller.

Image forming apparatus that controls cleaning ability of cleaner and control method thereof

In an image forming apparatus, the image bearing member has a surface and configured to rotate about an axis. The collection device is in contact with the surface, and configured to collect materials adhered to the surface. The developing roller is configured to provide a charged toner having a first polarity. The processor is configured to perform: executing a print job in a printing period; executing, in a non-printing period, a first process in which the image bearing member is rotated at least one rotation while a holding bias is applied to the collection device, the holding bias having a second polarity opposite to the first polarity; and executing, in a non-printing period after the first process, a second process in which the image bearing member is rotated while an ejection bias is applied to the collection device, the ejection bias having the first polarity.

Image forming apparatus having image bearing member and collection device to collect materials adhered on the image bearing member

An image forming apparatus includes a photosensitive member, a charger, a developing device, a transfer device, a scraper, and a controller. The controller performs an image formation process to form the developer image on the photosensitive member by using the developing device. The controller acquires, as a first value, at least one of a value of the charging current flowing in the charger and a value of the transferring current flowing in the transfer device. The controller calculates an accumulation current value by using result of an integral of a second value over time. The second value is an absolute value of the first value. The controller performs a scraping process in which the scraper scrapes the photosensitive member when the accumulation current value reaches a threshold value.

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Nagoya, Japan

Chieko Mimura