Patents by Inventor Jeong-jai Choi

Jeong-jai Choi has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8351810
    Abstract: According to a method and apparatus for controlling a voltage of an image forming apparatus, a transferring roll resistance, which indicates the resistance between a transferring roller and a photoconductor drum, is detected by applying a first voltage to the transferring roller. A transferring voltage, which corresponds to the detected transferring roll resistance, is applied to the transferring roller with reference to a transferring table which corresponds to the paper resistance, and a transferring is performed on a printing paper by using a transferring roller to which a transferring voltage is applied.
    Type: Grant
    Filed: August 17, 2010
    Date of Patent: January 8, 2013
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jeong-Jai Choi
  • Patent number: 8326164
    Abstract: A charging voltage control method of an image forming apparatus and an image forming apparatus thereof. The charging voltage control method of the image forming apparatus includes: applying a charging voltage amount determined by referring to a basic lookup table which determines the charging voltage based on a system load; and correcting the applied charging voltage by using a first correction value which is determined based on a first correction lookup table which determines the first correction value based on a difference between a target current corresponding to the lifespan of the charging roller and a charging current.
    Type: Grant
    Filed: June 30, 2009
    Date of Patent: December 4, 2012
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jeong-Jai Choi
  • Publication number: 20110085810
    Abstract: According to a method and apparatus for controlling a voltage of an image forming apparatus, a transferring roll resistance, which indicates the resistance between a transferring roller and a photoconductor drum, is detected by applying a first voltage to the transferring roller. A transferring voltage, which corresponds to the detected transferring roll resistance, is applied to the transferring roller with reference to a transferring table which corresponds to the paper resistance, and a transferring is performed on a printing paper by using a transferring roller to which a transferring voltage is applied.
    Type: Application
    Filed: August 17, 2010
    Publication date: April 14, 2011
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventor: Jeong-Jai Choi
  • Patent number: 7809302
    Abstract: A charging apparatus includes a charging member to charge a surface of a photoconductive medium, a power unit to supply an electric power as a bias voltage to the charging member, and a resistor unit to reduce a ripple on the surface of the charging member. Accordingly, a stability of the charging apparatus is secured without using a separate power device.
    Type: Grant
    Filed: May 22, 2008
    Date of Patent: October 5, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jeong-jai Choi
  • Publication number: 20100061747
    Abstract: A charging voltage control method of an image forming apparatus and an image forming apparatus thereof. The charging voltage control method of the image forming apparatus includes: applying a charging voltage amount determined by referring to a basic lookup table which determines the charging voltage based on a system load; and correcting the applied charging voltage by using a first correction value which is determined based on a first correction lookup table which determines the first correction value based on a difference between a target current corresponding to the lifespan of the charging roller and a charging current.
    Type: Application
    Filed: June 30, 2009
    Publication date: March 11, 2010
    Applicant: Samsung Electronics Co., Ltd
    Inventor: Jeong-Jai CHOI
  • Patent number: 7574159
    Abstract: An image forming apparatus and a method of preventing a carrier from adhering to a photosensitive drum are provided. The image forming apparatus includes a photosensitive drum on which an electrostatic latent image is formed by an exposure unit, a main motor which rotates the photosensitive drum, an eraser unit which removes a potential charged on the photosensitive drum, and a controller which controls the eraser unit to remove a potential of the photosensitive drum while the photosensitive drum rotates due to an inertial force after the main motor stops rotating.
    Type: Grant
    Filed: March 9, 2006
    Date of Patent: August 11, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jeong-jai Choi
  • Patent number: 7536119
    Abstract: An image forming apparatus and method including a developing cartridge mounted in a main body of the image forming apparatus to receive a developer with a certain space occupancy of the developer with respect to an inner capacity thereof; a developer supply part connected to the developing cartridge to supply the developer; a sensor for detecting an amount of the developer in the developing cartridge; and a control part for controlling the developer supply part to restrict an amount of the developer for supply to the developing cartridge according to the amount of the developer detected by the sensor, thereby maintaining the space occupancy of the developer in the developing cartridge. Accordingly, the developer supplied to the developing cartridge can be in a certain range of space occupancy during printing, and as a result, density of the developer in a developing area can be uniform.
    Type: Grant
    Filed: June 9, 2005
    Date of Patent: May 19, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jeong-jai Choi
  • Publication number: 20090074443
    Abstract: A charging apparatus includes a charging member to charge a surface of a photoconductive medium, a power unit to supply an electric power as a bias voltage to the charging member, and a resistor unit to reduce a ripple on the surface of the charging member. Accordingly, a stability of the charging apparatus is secured without using a separate power device.
    Type: Application
    Filed: May 22, 2008
    Publication date: March 19, 2009
    Applicant: Samsung Electronics Co., Ltd
    Inventor: Jeong-jai CHOI
  • Patent number: 7398037
    Abstract: A process cartridge usable with an image forming apparatus includes a developing cartridge including a toner inlet and a shutter to open and close the toner inlet, and a toner cartridge detachably mounted to the developing cartridge and including a toner supply port to correspond with the toner inlet when connected with the developing cartridge. The shutter may be moved in a direction in which the toner cartridge is connected when the toner cartridge is connected to the developing cartridge, thereby opening the toner inlet, and the shutter may be moved in a direction in which the toner cartridge is detached when the toner cartridge is separated from the developing cartridge, thereby closing the toner inlet. Accordingly, when the toner cartridge is separated from the developing cartridge, the toner inlet of the developing cartridge is closed, thereby preventing leakage of toner through the toner inlet.
    Type: Grant
    Filed: September 15, 2005
    Date of Patent: July 8, 2008
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jeong-jai Choi
  • Patent number: 7392000
    Abstract: An image forming apparatus having a photoconductive drum to form an electrostatic latent image corresponding to a predetermined image by a laser beam scanned after being electrified to a predetermined electric potential, and a developing roller to rotate together with the photoconductive drum having a developing gap therebetween and to transfer a developer, which is a mixture of a toner and a carrier, to the photoconductive drum to form a toner image on the electrostatic latent image, wherein a linear velocity ratio of a linear velocity of the developing roller to a linear velocity of the photoconductive drum is provided at a predetermined ratio, which provides maximum quality of the toner image.
    Type: Grant
    Filed: May 12, 2004
    Date of Patent: June 24, 2008
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jeong-jai Choi
  • Patent number: 7382991
    Abstract: An apparatus and a method that displays a toner residual quantity includes: a calculation unit calculating a first prediction of toner residual quantity according to a dot count of printing data and calculating a second prediction of toner residual quantity according to a total actuating time of a toner supply motor; a determination unit determining whether the second prediction toner residual quantity is within a predetermined range of the first prediction toner residual quantity; and a user interface unit displaying the second prediction of toner residual quantity based on the determined result. A remaining amount value is displayed so that a user is informed of a toner replacement time.
    Type: Grant
    Filed: April 26, 2006
    Date of Patent: June 3, 2008
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jeong-Jai Choi
  • Patent number: 7333763
    Abstract: Disclosed is a developer collecting apparatus capable of preventing a developer collected from a photoconductive medium from clotting while being supplied to a developing unit. The developer collecting apparatus includes a developer collecting container including an inlet for inflow of a developer removed from a photoconductive medium by a cleaning member, and an outlet for discharge of the developer. The developer collecting apparatus also includes a developer storing container connected to the developer collecting container through a transport pipe and a vibration unit for preventing the developer from clotting and accumulating at the outlet of the developer collecting container and in the transport pipe.
    Type: Grant
    Filed: August 8, 2005
    Date of Patent: February 19, 2008
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jeong-Jai Choi
  • Publication number: 20060245770
    Abstract: An apparatus and a method that displays a toner residual quantity includes: a calculation unit calculating a first prediction of toner residual quantity according to a dot count of printing data and calculating a second prediction of toner residual quantity according to a total actuating time of a toner supply motor; a determination unit determining whether the second prediction toner residual quantity is within a predetermined range of the first prediction toner residual quantity; and a user interface unit displaying the second prediction of toner residual quantity based on the determined result. A remaining amount value is displayed so that a user is informed of a toner replacement time.
    Type: Application
    Filed: April 26, 2006
    Publication date: November 2, 2006
    Applicant: Samsung Electronics Co. Ltd.
    Inventor: Jeong-Jai Choi
  • Publication number: 20060222391
    Abstract: A method of and apparatus for controlling a transfer voltage in an electro-photographic image forming apparatus. A transfer roller resistance between a transfer roller and a photosensitive drum is detected with a constant voltage applied to the transfer roller in a state where the photosensitive drum and the transfer roller form a transfer nip. A paper resistance among the transfer roller, a paper, and the photosensitive drum is detected when the constant voltage is applied to the transfer roller while the paper approaches the transfer nip of the transfer roller. A paper type is determined and a transfer voltage is selectively applied to the transfer roller based on the detected transfer roller and paper resistances. Reference tables are stored in a memory to aid in determining the paper type and the applied transfer voltage.
    Type: Application
    Filed: March 27, 2006
    Publication date: October 5, 2006
    Applicant: Samsung Electronics Co., Ltd.
    Inventor: Jeong-jai Choi
  • Patent number: 7116927
    Abstract: A photosensitive drum of an image forming apparatus includes a drum main body having a hollow shape, and a vibration damping body spaced from an inner wall of the drum main body, having a hollow shape, formed with a plurality of slits, and expanding and closely contacting the inner wall of the drum main body while the drum main body rotates.
    Type: Grant
    Filed: December 7, 2004
    Date of Patent: October 3, 2006
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jeong-Jai Choi
  • Publication number: 20060204279
    Abstract: An image forming apparatus and a method of preventing a carrier from adhering to a photosensitive drum are provided. The image forming apparatus includes a photosensitive drum on which an electrostatic latent image is formed by an exposure unit, a main motor which rotates the photosensitive drum, an eraser unit which removes a potential charged on the photosensitive drum, and a controller which controls the eraser unit to remove a potential of the photosensitive drum while the photosensitive drum rotates due to an inertial force after the main motor stops rotating.
    Type: Application
    Filed: March 9, 2006
    Publication date: September 14, 2006
    Applicant: Samsung Electronics Co., Ltd.
    Inventor: Jeong-jai Choi
  • Patent number: 7092648
    Abstract: A method of controlling an amount of toner charging in an electrophotographic image forming apparatus using a two-component developing agent, and an apparatus using the method. The method includes counting an agitation time when a toner and a carrier are mixed and are agitated in an agitation region of a developing unit, and if the agitation time reaches a predetermined reference agitation time, supplying a predetermined amount of new toner to the agitation region to prevent overcharging of the toner.
    Type: Grant
    Filed: April 29, 2004
    Date of Patent: August 15, 2006
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jeong-jai Choi
  • Publication number: 20060062614
    Abstract: Disclosed is a developer collecting apparatus capable of preventing a developer collected from a photoconductive medium from clotting while being supplied to a developing unit. The developer collecting apparatus includes a developer collecting container including an inlet for inflow of a developer removed from a photoconductive medium by a cleaning member, and an outlet for discharge of the developer. The developer collecting apparatus also includes a developer storing container connected to the developer collecting container through a transport pipe and a vibration unit for preventing the developer from clotting and accumulating at the outlet of the developer collecting container and in the transport pipe.
    Type: Application
    Filed: August 8, 2005
    Publication date: March 23, 2006
    Inventor: Jeong-Jai Choi
  • Publication number: 20060062603
    Abstract: A process cartridge usable with an image forming apparatus includes a developing cartridge including a toner inlet and a shutter to open and close the toner inlet, and a toner cartridge detachably mounted to the developing cartridge and including a toner supply port to correspond with the toner inlet when connected with the developing cartridge. The shutter may be moved in a direction in which the toner cartridge is connected when the toner cartridge is connected to the developing cartridge, thereby opening the toner inlet, and the shutter may be moved in a direction in which the toner cartridge is detached when the toner cartridge is separated from the developing cartridge, thereby closing the toner inlet. Accordingly, when the toner cartridge is separated from the developing cartridge, the toner inlet of the developing cartridge is closed, thereby preventing leakage of toner through the toner inlet.
    Type: Application
    Filed: September 15, 2005
    Publication date: March 23, 2006
    Inventor: Jeong-jai Choi
  • Publication number: 20060018673
    Abstract: An image forming apparatus and method including a developing cartridge mounted in a main body of the image forming apparatus to receive a developer with a certain space occupancy of the developer with respect to an inner capacity thereof; a developer supply part connected to the developing cartridge to supply the developer; a sensor for detecting an amount of the developer in the developing cartridge; and a control part for controlling the developer supply part to restrict an amount of the developer for supply to the developing cartridge according to the amount of the developer detected by the sensor, thereby maintaining the space occupancy of the developer in the developing cartridge. Accordingly, the developer supplied to the developing cartridge can be in a certain range of space occupancy during printing, and as a result, density of the developer in a developing area can be uniform.
    Type: Application
    Filed: June 9, 2005
    Publication date: January 26, 2006
    Applicant: Samsung Electronics Co., Ltd.
    Inventor: Jeong-jai Choi