Brother Kogyo Kabushiki-Kaisha

Tsuyoshi Maruyama

Katsumi Inukai

Masahito Hamaya

Kazushi Shumiya

Kohei Kanehara

Hiroyuki Tsujihara

A heating device includes: an alternating current (AC) power supply line configured to supply AC current from an AC power supply; a heat generation unit configured to generate heat in accordance with the AC current; an energization regulation unit configured to regulate energization time of the AC current to the heat generation unit; a switching unit configured to switch a connection state between the AC power supply and the heat generation unit; and a high-voltage protection unit, which is connected between the AC power supply line at a rear stage of the switching unit, and which is configured to protect the energization regulation unit against an abnormal input high voltage.

Heating device and image forming apparatus

In a power supply device, the controller outputs a control signal specifying a voltage value. The voltage conversion unit converts a first voltage to a second voltage in response to a control signal specifying a voltage value output from the controller. The voltage conversion unit converts the first voltage to a start voltage, as the second voltage, in response to a first control signal specifying a start voltage value output from the controller and further converts the first voltage to a target voltage, as the second voltage, in response to a second control signal specifying a target voltage value output from the controller. A transition period of time is intervened between generation of the start voltage and generation of the target voltage during which the controller outputs a third control signal specifying the intermediate voltage value between the start voltage value and the target voltage value.

Power supply device performing voltage conversion

An image forming device, comprising: at least one photosensitive body; scorotron chargers that charge the at least one photosensitive body; a charge voltage applying circuit to which the scorotron chargers are commonly connected, the charge voltage applying circuit being configured to apply a voltage to the scorotron chargers; wires respectively provided for the scorotron chargers; grid electrodes respectively provided for the scorotron chargers; a current detection unit configured to detect a grid current of each of the grid electrodes; and a grid current control unit configured to execute a constant-current control for a maximum grid current which is a maximum of grid currents flowing through the grid electrodes so that the maximum grid current is kept at a first threshold larger than or equal to a reference value by adjusting an output of the charge voltage applying circuit.

Image forming device having a shared voltage supply and constant current control

A heating apparatus includes a switching circuit configured to switch on/off current-feeding from an AC power source to the heater, a temperature detector configured to detect a temperature of the heater, and a current-feed controller configured to execute a first current-feed mode of changing a current-feed ratio of current-feeding time to unit time by controlling switching of the switching circuit so that the temperature detected by the temperature detector falls within a target range. The current-feed controller executes a second current-feed mode of fixing the current-feed ratio to almost 100% or almost 0% during execution of the first current-feed mode in place of the first current-feed mode.

Heating apparatus and image forming apparatus having the same

An image forming apparatus, includes: at least one photosensitive element; a plurality of chargers configured to charge the at least one photosensitive element; a voltage applying circuit commonly connected to the plurality of chargers and configured to apply a voltage to the plurality of chargers; a current detecting unit configured to detect a current sum of current that flows to the plurality of chargers from the voltage applying circuit; and a control device configured to control the voltage applying circuit so that the current sum detected by the current detecting unit becomes equal to or larger than a reference value.

Image forming apparatus including chargers and a current detecing unit that detects a sum of currents of the chargers

An image forming apparatus is provided, which includes an image forming unit configured to form an image on a recording medium, a cleaned body that is an intended body to be cleaned, a cleaning member configured to clean at least attached matter, which is generated in image formation by the image forming unit, on the cleaned body, a backup member disposed to face the cleaning member across the cleaned body, a voltage supply unit configured to supply the backup member with a cleaning voltage having a polarity identical to a charge polarity of the attached matter, in an operation of cleaning the cleaned body, a detector configured to detect an electric quantity of the cleaning member when the cleaning voltage is supplied to the backup member by the voltage supply unit, and a controller configured to control the detected electric quantity of the cleaning member to be a predetermined value.

Image forming apparatus having a configuration to prevent electric discharge in a cleaning member

An image forming apparatus includes: a photoconductor; a charger configured to charge the photoconductor, the charger having a discharge wire and a grid; a charge-voltage applying device configured to generate charge voltage and apply the charge voltage to the discharge wire; and an abnormal-discharge detector provided between an output end portion of the charge-voltage applying device and the ground. The abnormal-discharge detector is configured to detect an abnormal discharge occurring in the charger by detecting an abnormal current passing via the grid and the ground upon occurrence of the abnormal discharge.

Image forming apparatus with abnormal discharge detection

An image forming apparatus includes: a photoconductor; a charger configured to charge the photoconductor, the charger including a discharge wire and a grid; a voltage applying circuit configured to generate charge voltage and apply the charge voltage to the discharge wire of the charger; a grid-current detector configured to detect a grid current passing through the grid; a controller configured to control the voltage applying circuit on the basis of a detection value detected by the grid-current detector so that the grid current is constant; an abnormal-discharge detector configured to detect an abnormal discharge occurring in the charger; and a suppression resistor configured to suppress abnormal discharge energy. The suppression resistor includes a first terminal and a second terminal. The first terminal is connected to the grid. The second terminal is connected to at least one of the grid-current detector and the abnormal-discharge detector.

Image forming apparatus

An image forming apparatus including: a plurality of photosensitive drums; a plurality of scorotron chargers provided for the plurality of photosensitive drums, respectively, a voltage application circuit commonly connected to the plurality of scorotron chargers, a plurality of wires provided for the plurality of scorotron chargers, respectively; a plurality of grid electrodes provided for the plurality of scorotron chargers, respectively; at least one of current detecting units provided for at least one of the plurality of grid electrodes, respectively, and at least one of the current detecting units detecting grid current which flows into at least one of the grid electrodes, respectively; and a control device configured to control the voltage application circuit such that at least one of the grid currents detected by at least one of the current detecting units become equal to or higher than a reference value.

An image forming apparatus includes a voltage applying unit for applying a voltage to an electric load; a sub control unit for controlling the voltage applying unit; a restarting unit for restarting the sub control unit in response to receipt of a restart signal; a determining unit for determining whether or not a restart of the sub control unit is an abnormal restart; and a main control unit. The main control unit generates a control start signal for allowing the voltage applying unit to start generation of the voltage, and the restart signal. When the determining unit determines that the restart of the sub control unit is an abnormal restart, the main control unit sends again the control start signal to the sub control unit.

Image forming apparatus and voltage applying device comprising a control unit for controlling another control unit when the other control unit is abnormally restarted

An image forming apparatus is provided. A first cleaning unit is configured to collect a particle deposited on an object. An applying unit is configured to apply a voltage to the first cleaning unit. A first detector is configured to detect a first current flowing between the first cleaning unit and the object. A controller is configured to control the applying unit. When the detected first current becomes equal to or greater than a first predetermined value, the controller controls the applying unit to reduce the voltage applied to the first cleaning unit so as to make the first current smaller than the first predetermined value.

An image forming apparatus includes: a carrier configured to carry developer; a voltage applying unit configured to apply a voltage to the carrier so that a carrier current flows from the voltage applying unit through the carrier; and a current detecting unit configured to detect the carrier current. The current detecting unit detects the carrier current at an uncharged portion of the carrier.

Image forming apparatus with reduced deterioration of the carrier carrying developer

There is provided an image forming device, including: a first electrical load; a second electrical load; a voltage generation circuit that generates a second voltage to be applied to the second electrical load; a shunt circuit that located between an output side of the voltage generation circuit and the first electrical load; and a controller that executes first control of controlling the shunt circuit to change a first voltage applied from the shunt circuit to the first electrical load to a first target level, and second control of controlling the voltage generation circuit to change the second voltage to a second target level. The controller executes voltage change suppression control of controlling the second voltage such that change of the second voltage becomes gentler as a difference between the first voltage and the first target level becomes larger.

Growing community of inventors

Nagoya, Japan

Tsuyoshi Maruyama