Abstract: A medium supplying apparatus of an image forming device capable of removing static electricity generating in medium supplying operation by a ground. The medium supplying apparatus includes a medium supplying cassette mounted in a main body of the image forming device, a knock-up plate disposed to be movable up and down in the medium supplying cassette by at least one elastic member and to support printing media, a pickup roller to pick up the printing media loaded on the knock-up plate, a separating unit disposed on medium supplying cassette to separate the printing media one by one when the printing media are picked up, and a ground unit to ground the knock-up plate and the separating unit to the main body.

Abstract: A bypass tray to be used in an image forming apparatus, the bypass tray including a knock-up plate resiliently biased in an upward direction; and at least one stopper provided at least one side of the knock-up plate, rotatably provided so as to restrict a position of the knock-up plate while moving up and down.

Abstract: An image forming apparatus, including a heat roller in which a heating source is embedded, a press roller installed close to the heat roller, the press roller contacting the heat roller with a predetermined pressurizing force to form a fixing nip, and at least two overheat prevention devices installed near the heat roller to cut off a power supply to the heating source upon an overheating of the heat roller. One of the overheat prevention devices is installed at portion of the heat roller corresponding to a location within a width of a recording medium passing through the fixing nip and another is installed at a site near an end of the heat roller corresponding to a location outside the width of the recording medium.

Abstract: An image forming apparatus is provided having a printing unit including a detachable developer cartridge. The apparatus prints an image on a sheet using an electrophotographic process. A tray is provided to receive a sheet discharged after the completion of printing. An auxiliary tray is pivotably installed on the tray and has a first position folded over the tray and a second position to increase the length of the tray. The auxiliary tray pivots to the second position when the developer cartridge is mounted in the printing unit.

Abstract: A developer includes a developer frame in which a developing agent is contained, a development roller that is rotatably disposed inside the developer frame. Coupling means couples the development roller to the developer frame. The coupling means includes a gear member that is rotatably mounted to the developer frame and engages a first gear disposed outside the developer to transfer a rotational force. A development roller end portion rotates with the gear member in the same direction about the same rotational shaft as the gear member. An image forming apparatus includes a photosensitive medium on which an electrostatic latent image corresponding to an image to be printed is formed through light scanning and the developer, which applies a developing agent to the photosensitive medium to develop the image into a visible image.

Abstract: A medium supplying apparatus of an image forming device capable of removing static electricity generating in medium supplying operation by a ground. The medium supplying apparatus includes a medium supplying cassette mounted in a main body of the image forming device, a knock-up plate disposed to be movable up and down in the medium supplying cassette by at least one elastic member and to support printing media, a pickup roller to pick up the printing media loaded on the knock-up plate, a separating unit disposed on medium supplying cassette to separate the printing media one by one when the printing media are picked up, and a ground unit to ground the knock-up plate and the separating unit to the main body.

Abstract: A paper feeding unit of an image forming apparatus, which includes: a pickup roller; a first feed roller to feed the paper in a required direction; and a reverse roller to prevent a plurality of sheets of paper from being fed by rotating in an opposite direction to the first feed roller and to separate the paper into individual sheets, wherein the first feed roller has a contact section in contact with the reverse roller and a non-contact section where the first feed roller is apart from the reverse roller and the first feed roller feeds the paper by making a one-time rotation and stops rotating with the non-contact section facing the reverse roller. Since the feed roller and the reverse roller are put apart from each other in a waiting mode, the rollers can be protected from abrasion and paper can be fed smoothly.

Abstract: A method of measuring a paper size using a paper feeder having a fixedly mounted body part and a fastener apparatus movable depending on the paper size includes receiving light reflected from the body part with respect to an amount of a sent light, measuring the amount of the received light, and extracting information on a paper size corresponding to the measured amount of light from stored information. The extracted information of the paper size can be transmitted to a display unit, so that a user can recognize the information.

Abstract: An image forming apparatus, including a heat roller in which a heating source is embedded, a press roller installed close to the heat roller, the press roller contacting the heat roller with a predetermined pressurizing force to form a fixing nip, and at least two overheat prevention devices installed near the heat roller to cut off a power supply to the heating source upon an overheating of the heat roller. One of the overheat prevention devices is installed at portion of the heat roller corresponding to a location within a width of a recording medium passing through the fixing nip and another is installed at a site near an end of the heat roller corresponding to a location outside the width of the recording medium.

Abstract: Disclosed is an image forming apparatus, including a body in which toner is applied to a printed side of a print medium during a printing operation. The apparatus includes a medium transferring path defined in the body, along which the print medium is transferred during the printing operation, a sensor actuator, disposed in the medium transferring path, to be pivoted by the print medium as the print medium is transferred, a toner sticking prevention member, disposed on the sensor actuator, to contact the printed side of the print medium as the print medium is transferred passed the sensor actuator, the toner sticking prevention member being made of materials to which the toner does not stick, a paper sensor to sense the pivoting of the sensor actuator, and a control portion to perceive the transfer of the print medium according to a signal of the paper sensor.

Abstract: A bypass tray to be used in an image forming apparatus, the bypass tray including a knock-up plate resiliently biased in an upward direction; and at least one stopper provided at at least one side of the knock-up plate, rotatably provided so as to restrict a position of the knock-up plate while moving up and down.

Abstract: A paper feeding unit of an image forming apparatus, which includes: a pickup roller; a first feed roller to feed the paper in a required direction; and a reverse roller to prevent a plurality of sheets of paper from being fed by rotating in an opposite direction to the first feed roller and to separate the paper into individual sheets, wherein the first feed roller has a contact section in contact with the reverse roller and a non-contact section where the first feed roller is apart from the reverse roller and the first feed roller feeds the paper by making a one-time rotation and stops rotating with the non-contact section facing the reverse roller. Since the feed roller and the reverse roller are put apart from each other in a waiting mode, the rollers can be protected from abrasion and paper can be fed smoothly.

Abstract: A developer includes a developer frame in which a developing agent is contained, a development roller that is rotatably disposed inside the developer frame. Coupling means couples the development roller to the developer frame. The coupling means includes a gear member that is rotatably mounted to the developer frame and engages a first gear disposed outside the developer to transfer a rotational force. A development roller end portion rotates with the gear member in the same direction about the same rotational shaft as the gear member. An image forming apparatus includes a photosensitive medium on which an electrostatic latent image corresponding to an image to be printed is formed through light scanning and the developer, which applies a developing agent to the photosensitive medium to develop the image into a visible image.

Abstract: An image forming apparatus is provided having a printing unit including a detachable developer cartridge. The apparatus prints an image on a sheet using an electrophotographic process. A tray is provided to receive a sheet discharged after the completion of printing. An auxiliary tray is pivotably installed on the tray and has a first position folded over the tray and a second position to increase the length of the tray. The auxiliary tray pivots to the second position when the developer cartridge is mounted in the printing unit.

Abstract: A method of measuring a paper size using a paper feeder having a fixedly mounted body part and a fastener apparatus movable depending on the paper size includes receiving light reflected from the body part with respect to an amount of a sent light, measuring the amount of the received light, and extracting information on a paper size corresponding to the measured amount of light from stored information. The extracted information of the paper size can be transmitted to a display unit, so that a user can recognize the information.