Abstract: A method of compensating for a light amount drift of a photosensor used in an image control device, wherein the photosensor includes a light emitting portion and a light receiving portion which projects light onto an image control mark formed on an intermediate transfer medium of a printer and detects an optical signal reflected by the image control mark, thereby controlling the quality of an image. In the compensation method, the light amount drift is calculated by projecting light on the intermediate transfer medium, detecting an amount of light reflected by the intermediate transfer medium, and comparing the detected light amount with a pre-set reference light amount. The detected light amount is then corrected to be substantially equal to the reference light amount.

Abstract: A method of compensating for a light amount drift of a photosensor used in an image control device, wherein the photosensor includes a light emitting portion and a light receiving portion which projects light onto an image control mark formed on an intermediate transfer medium of a printer and detects an optical signal reflected by the image control mark, thereby controlling the quality of an image. In the compensation method, the light amount drift is calculated by projecting light on the intermediate transfer medium, detecting an amount of light reflected by the intermediate transfer medium, and comparing the detected light amount with a pre-set reference light amount. The detected light amount is then corrected to be substantially equal to the reference light amount.

Abstract: A device and a method for detecting the position of a developing unit mounted in an image forming apparatus are provided.

Abstract: An image forming apparatus is disclosed. Zener diode separately installed to correspond to each developing device so as to form a difference in potential between the developing bias voltage and the supply bias voltage of each developing device, is installed at a common end, so that a deviation of the developing voltage applied to the developing device affected by a deviation of Zener diode components can be reduced, resulting in an increased color image quality. In addition, the Zener diode is installed in a common end, such that the number of Zener diodes is reduced, resulting in a reduction in production costs.

Abstract: A method and apparatus for controlling registration sensors are provided, in which a transfer unit transfers an electrostatic latent image onto a printing medium, at least one registration sensor senses image alignment errors by irradiating light to the transfer unit to sense reflected light, a sensor data storage unit stores characteristics data of the respective registration sensors, and a sensor control unit controls the registration sensors based on the characteristics data of the respective registration sensors, wherein the registration sensors are placed into the transfer unit. Accordingly, time for performing an algorithm of color registration can be reduced, and registration can be achieved correctly in a short time, irrespective of a set frame of the image forming apparatus.

Abstract: An image forming apparatus includes a main controller unit provided in a main body of the image forming apparatus. The main controller includes a replacement component management memory to store lifespan information of a replacement component is provided in An authentication operation is performed with respect to the replacement component management memory, and the lifespan information of the replacement component is encrypted and stored in the replacement component management memory. Accordingly, the security of the main controller unit may be enhanced and illegal use of the replacement component may be prevented.

Abstract: An image forming apparatus including: a body; an electronic unit; a replaceable unit that is detachably installed within the body; a power supply that generates and outputs a predetermined operation voltage; a high voltage generating part that receives the operation voltage and generates and outputs a high voltage; an electronic unit driving part that receives the operation voltage and regulates a driving voltage supplied to the electronic unit; and a controller that controls the power supply to cut off the operation voltage if the replaceable unit is not installed within the body. Also taught is a method of operating the image forming apparatus.

Abstract: A device and a method for detecting the position of a developing unit mounted in an image forming apparatus are provided.

Abstract: An apparatus to control color registration and image density and a method of calculating a color registration error. The apparatus includes registration marks formed on a transfer belt such that each of the registration marks includes a scan direction component and a slanting direction component at an angle with respect to both the scan direction and the cross-scan direction. The apparatus further includes image density marks formed on the transfer belt, having predetermined image densities, and a registration and image density sensor provided above the registration marks and the image density marks to radiate beams onto the registration marks and the image density marks. The sensor receives beams reflected from the registration marks and the image density marks to produce detection signals, and obtains registration information and image density information from the detection signals.

Abstract: An apparatus to control color registration and image density and a method of calculating a color registration error. The apparatus includes registration marks formed on a transfer belt such that each of the registration marks includes a scan direction component and a slanting direction component at an angle with respect to both the scan direction and the cross-scan direction. The apparatus further includes image density marks formed on the transfer belt, having predetermined image densities, and a registration and image density sensor provided above the registration marks and the image density marks to radiate beams onto the registration marks and the image density marks. The sensor receives beams reflected from the registration marks and the image density marks to produce detection signals, and obtains registration information and image density information from the detection signals.

Abstract: An image forming apparatus including a power supply unit which supplies high voltage AC power, a developing unit having at least one developing roller to receive first AC power from the power supply unit to supply a developer to an image receptor, and an erasing unit to receive second AC power to attenuate high frequency noise of the developing unit.

Abstract: An image forming apparatus is disclosed. The image forming apparatus includes a body having an opening perforated in one side thereof, a developing unit detachably mounted to the body through the opening, a body cover configured to cover a rear portion of the developing unit in a mounting direction of the developing unit and adapted to open or close the opening, and a memory unit provided at the rear portion of the developing unit and having a developing device terminal. The body cover includes a body terminal to come into contact with the memory unit. Accordingly, an electrical connection between the developing unit and the body can be made less susceptible to vibration, etc. caused during operation of a drive motor.

Abstract: A method and apparatus to control power supplied to a paper transfer belt (PTB) unit and a laser scanning unit (LSU) included in an image forming device includes the PTB unit to transfer a developed latent image onto a printing medium, the LSU to scan light onto a photosensitive medium, a first controller to control power supplied to the PTB unit and the LSU, and a connection unit to connect the PTB unit to the first controller, wherein the first controller controls the power supplied to the LSU according to a connection state of the connection unit.

Abstract: An image forming apparatus includes a printing engine to form an image on a printing medium through printing processes, an engine frame to support the printing engine having a driving system to drive the printing engine, a high voltage power supply provided in a surface of the engine frame to apply a high voltage to at least one of units performing the printing processes, a main board provided in a surface of the engine frame adjacent to the surface having the high voltage power supply, and having a system engine controller to control the printing engine and a video controller to control a video signal, first and second main connectors respectively provided at lateral sides of the high voltage power supply and the main board adjacent to each other, and a connection control line to connect the first and second main connectors.

Abstract: An image forming apparatus including: a body; an electronic unit; a replaceable unit that is detachably installed within the body; a power supply that generates and outputs a predetermined operation voltage; a high voltage generating part that receives the operation voltage and generates and outputs a high voltage; an electronic unit driving part that receives the operation voltage and regulates a driving voltage supplied to the electronic unit; and a controller that controls the power supply to cut off the operation voltage if the replaceable unit is not installed within the body. Also taught is a method of operating the image forming apparatus.

Abstract: Provided are a high voltage generator of an image forming apparatus, which simplifies a circuit structure and reduces the number of control signals by commonly using a roller resistance sensing circuit unit, and a method of sensing roller resistance. The high voltage generator applies high voltages to a plurality of rollers included in the image forming apparatus and senses resistance values of the rollers. The high voltage generator includes a plurality of voltage-pumping circuit units for providing high voltages to the respective rollers. A plurality of high voltage divide circuit units divide the high voltages output from the voltage-pumping circuit units. A multiplexer receives a plurality of divide signals output from the high voltage divide circuit units, selects and outputs a divide signal, which corresponds to a resistance of a roller to be sensed, based on a predetermined select signal.

Abstract: A device for and method of managing status information on a consumable for an image forming device by using memory included in the consumable is provided. The image forming device having more than one consumables and transferring an electrostatic image formed on a surface of a photosensitive medium onto paper comprises an image forming unit printing a predetermined image in response to a control of a central controller, and a management memory storing management information related to status information of the consumables. The central controller reads the consumable information including remaining lifetime of the consumable from a consumable memory including in the consumable, reads the management information from the management memory included in the image forming device, calculates an amount of use of the consumables during an operation of the image forming device, and updates the consumable information and the management information using the calculated amount of use.

Abstract: A method and apparatus to control power supplied to a paper transfer belt (PTB) unit and a laser scanning unit (LSU) included in an image forming device includes the PTB unit to transfer a developed latent image onto a printing medium, the LSU to scan light onto a photosensitive medium, a first controller to control power supplied to the PTB unit and the LSU, and a connection unit to connect the PTB unit to the first controller, wherein the first controller controls the power supplied to the LSU according to a connection state of the connection unit.

Abstract: The present invention relates to an apparatus for managing consumables of an image forming apparatus widely used in printers, multi-function printers, and so on. The apparatus of the present invention includes memory devices provided in the consumables for writing and reading data related to the consumables and for managing the consumables. As such the present invention uses less signal lines for a development cartridge, informs a user to refill the consumables, and is less sensitive to noise due to the digital management of consumables.

Abstract: A method and apparatus for controlling registration sensors are provided, in which a transfer unit transfers an electrostatic latent image onto a printing medium, at least one registration sensor senses image alignment errors by irradiating light to the transfer unit to sense reflected light, a sensor data storage unit stores characteristics data of the respective registration sensors, and a sensor control unit controls the registration sensors based on the characteristics data of the respective registration sensors, wherein the registration sensors are placed into the transfer unit. Accordingly, time for performing an algorithm of color registration can be reduced, and registration can be achieved correctly in a short time, irrespective of a set frame of the image forming apparatus.