Samsung Electronics Co., Ltd.

Cheol-ju Yang

Su-kyoung Chae

Jun-bae Jeon

Yong-geun Kim

Seung-deog An

Woo-jung Shim

Yoon-seop Eom

Min-seon Kim

Moon-bae Park

Gun-ho Kim

Sang-sin Park

Jin-su Yun

Jung-woo Son

Young-joon Lee

A method and apparatus for forming an image determine if printing paper is properly picked up, and printing data is transferred to an intermediate transfer belt (ITB). When it is sensed that the printing paper is not properly picked up, picking up the printing paper is retried considering a revolution cycle of the ITB. Thus, the frequency of errors can be decreased, and a user's convenience can be increased because picking up the printing paper is automatically retried whenever mis-pick up occurs instead of displaying an error. Further, wasting of toner is decreased.

Method and apparatus for forming image

A system and method of controlling printing are disclosed. The system and method comprise inputting image data printed by a printing section and a preset value for a print medium's size corresponding to the image data; measuring a size of each print medium being fed to the printing section; comparing the measured value for the each measured print medium and the preset value for the print medium's size; counting the number of times in which difference is occurred between the measured value and the preset value; and determining whether the print mediums fed to the printing section are different from the preset print medium's size by comparing the counted number of times and a predetermined reference number of times.

Printing system for preventing errors due to a double fed paper medium and method of controlling the same

A printer and a method of driving a cooling fan of the printer include a storage unit temporarily stores printing option data and image data, and a control unit controls an operation of a printing unit in one of a warming-up mode, a standby mode, a printing mode and a sleep mode based on the printing option data and the image data as inputted into the control unit. The control unit outputs a control signal variably controlling an RPM (Rotation Per Minute) of the cooling fan based on the operation mode and a printing speed of the printing unit. A cooling fan driving unit drives the cooling fan at a different RPM based on the control signal input from the control unit. Accordingly, the printer and the method of driving the cooling fan of the printer are capable of shortening the warming-up time to increase an initial printing speed, preventing the printing unit from being overheated, extending a lifespan of the cooling fan, and reducing a power consumption.

Printer and method of driving cooling fan of printer

Disclosed are a method of preventing overheating of a fuser assembly and an apparatus using the same. The method of preventing overheating of a fuser assembly includes inspecting whether a temperature of a fuser assembly is higher than a predetermined temperature. If the temperature of the fuser assembly is higher than the predetermined temperature it is determined whether there is a print command. A print sheet is passed through the fuser assembly, and conveyed to a predetermined location when there is no print command. The temperature is again inspected if there is no print command. If the temperature is lower than the predetermined temperature it is determined whether a predetermined time has lapsed. The temperature is again inspected if the predetermined time did not lapse.

Method of preventing overheating of fuser assembly and apparatus using the same

An image forming apparatus and a method of detecting a home position error are provided. The image forming apparatus includes a plurality of developing units, a cam shaft, and a plurality of cams that are formed on the cam shaft to correspond to the respective developing units. A power transmitting element is installed between the plurality of developing units and the plurality of cams and selectively transmits a rotational force of a driving source to the plurality of developing units according to a rotational phase of the cam shaft. An indicating element is installed on the cam shaft and includes a plurality of indicating units. A sensor senses the plurality of indicating units. A home position error is detected each time when the indicating units pass through the sensor.

Image forming apparatus and method of detecting home position error by sensing an indicating unit

An apparatus and method of driving a transfer belt are disclosed. The apparatus and method comprise driving the transfer belt provided in an image forming apparatus by a predetermined distance when the transfer belt has been stopped for a predetermined time, and thus varying the contact portion with a plurality of rollers provided on the transfer belt. Image contamination due to deformation on the belt can be avoided. Additionally, because the rotation time of the driving source can be set to a predetermined time during the power-saving mode, power consumption can be minimized.

Apparatus and method of driving a transfer belt

Disclosed is a method for controlling the temperature of a heat roller and an image forming apparatus based on the same. The image forming apparatus of the present invention includes: a heat roller for heating a printing paper having a toner image formed thereon to completely fuse the toner image to the printing paper; a heat lamp for heating the heat roller; and a controller for controlling the driving of the heat lamp, whereby the heat roller is maintained at a designated target temperature level during a pre-printing period. As such, it becomes possible to prevent a problem with the fusing process caused by low temperature of the heat roller during the pre-printing period for subsequent printing.

Method for controlling temperature of heat roller and image forming apparatus based on the same

Provided is a method of controlling a fusing speed of an image forming apparatus. Determination is made as to whether a sheet of paper to be printed is a special-purpose sheet. Determination is made as to whether a lengthof the sheet of paper is shorter than a distance Lbetween a second transfer roller and a fusing unit. Determination is also made as to whether the lengthof the sheet of paper is shorter than a distance Lbetween a first transfer roller and the second transfer roller. Determination is made as to whether the lengthof the sheet of paper is longer than the distance L0 between the first transfer roller and the second transfer roller.

Method of controlling fusing speed of image forming apparatus

A controlling method of an image forming apparatus for finely controlling the sensitivity of a density sensor in response to various changes of a printing environment. The controlling method of the image forming apparatus uses one or more of the following methods, alone or in any combination, to control the sensitivity of a density sensor. The methods can include a sensitivity correction method for controlling an output signal of the density sensor according to amount of light irradiated to an image carrier from a light source, a sensitivity correction method for correcting a reference value according to an output signal of the density sensor, and a sensitivity correction method for changing the signal output from the density sensor using a predetermined process.

Control method for correcting sensitivity of toner density sensor of image forming apparatus

Provided is a method and apparatus for preventing a transfer roller from being contaminated by toner in an image forming system, the method comprising determining a size of paper based on a time when front and rear ends of the paper are detected by a paper feeding sensor; comparing a size of an image formed on a photosensitive drum with the size of the paper; and if the size of the paper is the same as or smaller than the size of the image, determining a separation time of a transfer roller from a transfer belt in consideration of a delay time when the transfer roller is mechanically separated from the transfer belt after a separation command is applied to the transfer roller.

Method and apparatus for preventing transfer roller from being contaminated in image forming system

A duplex electro-photographic developing machine including a printing medium tray loading a printing medium, a tray open/closed detecting unit detecting whether the printing medium tray has been opened and closed, a transferring roller transferring a toner image onto the printing medium, a resistance measuring unit measuring a resistance value of the printing medium passing the transferring roller, and a concentration controlling unit controlling a concentration of the toner image according to the measured resistance value measured by the resistance measuring unit in response to the printing medium tray having changed from an open state to a close state.

Duplex electro-photographic developing machine and method of controlling toner image concentration thereof

An image forming apparatus is configured to facilitate design modification. The image forming apparatus has an engine mechanism to carry out a printing job with respect to a print data applied from an external device, an image processing unit to convert the print data into image data, and an engine controlling unit to control the engine mechanism to carry out the print job with respect to the image data. The engine controlling unit and the image processing unit are arranged on a single printed circuit board (PCB) in which a first and a second division are defined, with the engine controlling unit being arranged in the first division and the image processing unit being arranged in the second division. A circuit element in the second division is shared by the engine controlling unit and the image processing unit to reduce costs and redesign time.

Growing community of inventors

Suwon-si, South Korea

Cheol-ju Yang