Abstract: A transfer device and an image forming apparatus having the same are provided. Shapes of cam profiles of first cam members and second cam members controlling movement of first slider members moving a first transfer roller corresponding to a black developer, and second slider members moving a second transfer roller corresponding to a color developer. Times are different as when movement of the first slider members is completed and when movement of the second slider members is completed in mode conversion among a ready mode, a mono mode and a color mode, and thus a driving load generated when the first and second cam members are rotated is reduced, non-uniformity of the rotating speeds of the first and second cam members is reduced, and problems generated due to non-uniform rotating speeds of the cam members are reduced.

Abstract: An image forming apparatus including a side cover rotatably installed to open and close an opening provided at a body thereof while rotating, a first transfer unit to which a visible image of photoconductors of developing units is transferred, and a second transfer unit movably installed at the side cover to transfer the visible image to a printing medium, wherein the second transfer unit is provided at both sides thereof with a plurality of guide protrusions to perform a position restriction, and the body is provided at both sidewalls of inside thereof with a plurality of guide members to support the plurality of guide protrusions such that the second transfer unit is supported against both sidewalls of the inside of the body through the guide protrusion and the guide member, thereby reducing a reaction force applied to the side cover.

Abstract: An image forming apparatus capable of increasing the speed of successively discharging printed printing media in order to increase the overall print speed and a control method thereof. The image forming apparatus includes a first discharge roller to feed printed printing medium rearward from a print unit disposed at an inner front portion of a main body, a reverse roller to reverse a moving direction of the printed printing medium fed from the first discharge roller from a rear to a front of the main body, a second discharge roller to discharge the printed printing medium whose moving direction is reversed outside, and an intermediate discharge roller unit which is provided between the first discharge roller and the reverse roller, the intermediate discharge roller unit including a main roller, a sub discharge roller and a sub supply roller which are in contact with the main roller.

Abstract: A transfer device and an image forming apparatus having the same are provided. Shapes of cam profiles of first cam members and second cam members controlling movement of first slider members moving a first transfer roller corresponding to a black developer, and second slider members moving a second transfer roller corresponding to a color developer. Times are different as when movement of the first slider members is completed and when movement of the second slider members is completed in mode conversion among a ready mode, a mono mode and a color mode, and thus a driving load generated when the first and second cam members are rotated is reduced, non-uniformity of the rotating speeds of the first and second cam members is reduced, and problems generated due to non-uniform rotating speeds of the cam members are reduced.

Abstract: An image forming apparatus including a side cover rotatably installed to open and close an opening provided at a body thereof while rotating, a first transfer unit to which a visible image of photoconductors of developing units is transferred, and a second transfer unit movably installed at the side cover to transfer the visible image to a printing medium, wherein the second transfer unit is provided at both sides thereof with a plurality of guide protrusions to perform a position restriction, and the body is provided at both sidewalls of inside thereof with a plurality of guide members to support the plurality of guide protrusions such that the second transfer unit is supported against both sidewalls of the inside of the body through the guide protrusion and the guide member, thereby reducing a reaction force applied to the side cover.

Abstract: A transfer device and an image forming apparatus having the same are provided. Shapes of cam profiles of first cam members and second cam members controlling movement of first slider members moving a first transfer roller corresponding to a black developer, and second slider members moving a second transfer roller corresponding to a color developer. Times are different as when movement of the first slider members is completed and when movement of the second slider members is completed in mode conversion among a ready mode, a mono mode and a color mode, and thus a driving load generated when the first and second cam members are rotated is reduced, non-uniformity of the rotating speeds of the first and second cam members is reduced, and problems generated due to non-uniform rotating speeds of the cam members are reduced.

Abstract: An image forming apparatus including a side cover rotatably installed to open and close an opening provided at a body thereof while rotating, a first transfer unit to which a visible image of photoconductors of developing units is transferred, and a second transfer unit movably installed at the side cover to transfer the visible image to a printing medium, wherein the second transfer unit is provided at both sides thereof with a plurality of guide protrusions to perform a position restriction, and the body is provided at both sidewalls of inside thereof with a plurality of guide members to support the plurality of guide protrusions such that the second transfer unit is supported against both sidewalls of the inside of the body through the guide protrusion and the guide member, thereby reducing a reaction force applied to the side cover.

Abstract: An image forming apparatus capable of reducing a space required to install a transfer unit to achieve a compact body size. The image forming apparatus can include a body, a frame installed in the body, a transfer unit installed inside the frame, and a waste toner recovery device to recover waste toner collected from the transfer unit. The waste toner recovery device can include a first delivery unit to deliver the waste toner in a first direction, and a second delivery unit to deliver the waste toner, delivered from the first delivery unit, in a second direction. The second delivery unit can be movably installed to the frame and can be coupled to or detached from the first delivery unit via movement thereof.

Abstract: An image forming apparatus includes a main body, a developing unit, a drawer movably installed at the main body and including a tray and a cover. The cover includes a first operation section and a second operation section, an interlocking member to be moved along with the drawer in the first operation section of the cover, and a lift member to be vertically moved according to movement of the interlocking member, wherein the developing unit is provided with a first connection terminal. The lift member is arranged with a second connection terminal, and the tray is arranged with a third connection terminal connected to the second connection terminal according to the position of the second connection terminal so that the second and third connection terminals are disconnected prior to extraction of the tray from the main body.

Abstract: An image forming apparatus capable of increasing the speed of successively discharging printed printing media in order to increase the overall print speed and a control method thereof. The image forming apparatus includes a first discharge roller to feed printed printing medium rearward from a print unit disposed at an inner front portion of a main body, a reverse roller to reverse a moving direction of the printed printing medium fed from the first discharge roller from a rear to a front of the main body, a second discharge roller to discharge the printed printing medium whose moving direction is reversed outside, and an intermediate discharge roller unit which is provided between the first discharge roller and the reverse roller, the intermediate discharge roller unit including a main roller, a sub discharge roller and a sub supply roller which are in contact with the main roller.

Abstract: An image forming apparatus capable of increasing the speed of successively discharging printed printing media in order to increase the overall print speed and a control method thereof. The image forming apparatus includes a first discharge roller to feed printed printing medium rearward from a print unit disposed at an inner front portion of a main body, a reverse roller to reverse a moving direction of the printed printing medium fed from the first discharge roller from a rear to a front of the main body, a second discharge roller to discharge the printed printing medium whose moving direction is reversed outside, and an intermediate discharge roller unit which is provided between the first discharge roller and the reverse roller, the intermediate discharge roller unit including a main roller, a sub discharge roller and a sub supply roller which are in contact with the main roller.

Abstract: An image forming apparatus and a transfer device thereof the transfer device including an intermediate transfer belt, at least one intermediate transfer belt roller to maintain tension in the intermediate transfer belt, transfer rollers to press the intermediate transfer belt to image carriers and a state changing device. The state changing device includes: a rotating shaft; a first cam member coupled to the rotating shaft and configured to move the intermediate transfer belt roller to reduce the tension applied to the intermediate transfer belt; and a second cam member coupled to the rotating shaft and configured to move at least one of the transfer rollers away from the intermediate transfer belt.

Abstract: An image forming apparatus includes a main body, a developing unit, a drawer movably installed at the main body and including a tray and a cover. The cover includes a first operation section and a second operation section, an interlocking member to be moved along with the drawer in the first operation section of the cover, and a lift member to be vertically moved according to movement of the interlocking member, wherein the developing unit is provided with a first connection terminal. The lift member is arranged with a second connection terminal, and the tray is arranged with a third connection terminal connected to the second connection terminal according to the position of the second connection terminal so that the second and third connection terminals are disconnected prior to extraction of the tray from the main body.

Abstract: An image forming apparatus capable of preventing simultaneous delivery of two sheets of paper when they are supplied from a paper supply device, thereby improving operational reliability of the paper supply device. The image forming apparatus includes a body incorporating a printing device, a first paper supply unit, in which first paper is loaded, a second paper supply unit, on which second paper is disposed, at least one feed roller to deliver the second paper disposed on the second paper supply unit, a pickup roller to pick up the first paper from the first paper supply unit, and a pickup pad, which is located at a first position to contact the pickup roller when the pickup roller picks up the first paper from the first paper supply unit, and which is located at a second position spaced apart from the pickup roller when the second paper disposed on the second paper supply unit is delivered by the feed roller.

Abstract: A fusing unit for an image forming apparatus, including a heating roller to apply heat to a printable medium; a first pressing roller facing the heating roller so as to press the printable medium against the heating roller; a second pressing roller disposed in front of the first pressing roller in a proceeding direction of the printable medium press the printable medium against the heating roller; and a driving unit to transmit a rotation force to the second pressing roller so that a surface linear speed of the second pressing roller is greater than a surface linear speed of the heating roller.

Abstract: An image forming apparatus including: a main body including a manipulating unit which manipulates the power transmission unit, a driving component having a driving assembling member which is disposed in a direction of a rotational driving axial line; a developing device which has a driven assembling member capable of being engaged with and disengaged from the driving assembling member along the direction of the rotational driving axial line; a power transmission unit which is disposed between the driving assembling member and the driven assembling member and enables at least one of the driving assembling and the driven assembling member is moveable in the direction of the rotational driving axial line.

Abstract: An image forming apparatus includes a developing unit to form an image using a developing agent on one side of a printing medium transported along a simplex printing path, a fixing unit to fix the developing agent on the printing medium, a discharging roller to discharge the printing medium that passes the fixing unit, and a first driving source to drive the developing unit, the fixing unit and the discharging roller.

Abstract: A tandem color image forming apparatus includes a plurality of photosensitive bodies driven by one driving source and having a shaft gear, and power transmission members engaged with the shaft gears of the plurality of the photosensitive bodies to transmit a driving force generated from the driving source to each of the plurality of the photosensitive bodies. At least one color registration compensation unit is disposed between the power transmission members. The color image forming apparatus employs the color registration compensation unit so that each photosensitive body can be synchronized and registration errors can be minimized.

Abstract: A developing unit and an image forming apparatus having the developing unit are disclosed. The developing unit includes a developing unit main body having a supporting groove that contacts and is supported by the supporting protrusion of a frame when the developing unit is mounted on the mounting frame. A photoconductor is rotatably disposed in the developing unit main body and has ends that form a supporting shaft and are supported by a supporting unit. A driven unit is disposed in the developing unit main body and geared with the driving unit when the developing unit main body is mounted on the mounting frame. One of side surfaces of the developing unit main body includes an interference unit that interferes with the mounting frame and push the developing unit main body into engagement with the driving gear when the developing main body is mounted on the mounting frame.

Abstract: An image forming apparatus includes a transfer unit to transfer a toner to a printing medium, and a waste toner recovery unit to convey a waste toner recovered from the transfer unit. A first driving source for driving the transfer unit is configured independently of a second driving source for driving the waste toner recovery unit, so that deterioration in the quality of image caused by the waste toner recovery unit can be minimized.