Abstract: An image forming apparatus has a photosensitive body on which an electrostatic latent image is formed. A developing unit develops the electrostatic latent image on the photosensitive body with a developer to form a developer image. The developer image on the photosensitive body is transferred onto an intermediate transfer belt in an intermediate transfer unit. The transfer unit transfers the developer image transferred on the intermediate transfer belt onto a printing medium. A cleaning unit cleans any developer remaining on the photosensitive body, and a printing medium guide unit is disposed on the cleaning unit to guide the printing medium until the printing medium enters the transfer nip between the intermediate transfer belt and the transfer unit.

Abstract: A power transmitting device that allows a rotation driving unit to stably rotate at a constant angular velocity while overcoming an effect of backlash of a gear which is an element to transmitting power, a drive transmitting apparatus of an image forming apparatus that employs the power transmitting device, and an image forming apparatus that employs the power transmitting device. The power transmitting device includes a weighted rotor that has a weight larger than the rotation object and is connected to the rotation object to rotate along with the rotation object; and a viscous member to reduce a rotation force of the weighted rotor due to a viscosity of a fluid filled therein. The power transmitting device prevents change of the rotation speed of the rotation object due to a gear backlash by using the weight of a weighted rotor and a viscous braking force of a damping grease, and the anti-backlash function can be maintained during a long period of operation.

Abstract: An image forming apparatus, including a storing part in which a print medium is stored, an image forming part to form an image on the print medium, a discharging part to discharge the print medium to an exterior of the apparatus, and an electrostatic belt to attract the print medium via static electricity, and to transfer the attracted print medium.

Abstract: A one-way power transmission unit has a force-fitting feature formed on at least one of an outer circumference of a boss of a driving member and an inner circumference of a boss hole of a latch member, for force-fitting the driving member into the latch member with a friction which is less than a load exerted to a driven member. A method of one-way power transmission includes force-fitting the driving member into the latch member with a friction which is less than a load exerted to a driven member. Since the latch member force-fits over the boss of the driving member, the driving member and the latch member rotate together with each other when the driving member switches from a driving force disconnection state to a driving force connection state, and thus, engagement of latch gears of the driving member and the latch member is reliably achieved. Accordingly, the time interval between switching from the driving force disconnection state to the connection state can be maintained to be essentially constant.

Abstract: An image forming apparatus has a photosensitive body on which an electrostatic latent image is formed. A developing unit develops the electrostatic latent image on the photosensitive body with a developer to form a developer image. The developer image on the photosensitive body is transferred onto an intermediate transfer belt in an intermediate transfer unit. The transfer unit transfers the developer image transferred on the intermediate transfer belt onto a printing medium. A cleaning unit cleans any developer remaining on the photosensitive body, and a printing medium guide unit is provided at the cleaning unit to guide the printing medium until the printing medium enters the transfer nip between the intermediate transfer belt and the transfer unit. The printing medium guide unit is formed at a side of the cleaning unit adjacent to the printing medium conveying path.

Abstract: A one-way power transmission unit has force-fitting means formed on at least one of an outer circumference of a boss of a driving member and an inner circumference of a boss hole of a latch member, for force-fitting the driving member into the latch member with a friction which is less than a load exerted to a driven member. A method of one-way power transmission including, inter alia, force-fitting the driving member into the latch member with a friction which is less than a load exerted to a driven member. Since the latch member force-fits over the boss of the driving member, the driving member and the latch member rotate together with each other when the driving member switches from a driving force disconnection state to a driving force connection state, and thus, engagement of latch gears of the driving member and the latch member is reliably achieved.

Abstract: A coupling apparatus, a development cartridge, and an electrophotographic printer having the coupling apparatus. The coupling apparatus transfers a rotation force in a connected state. The coupling apparatus has a first coupler having a cylindrical-type connection portion at an end and a spiral rib spirally protruded at an outer circumference of the connection portion; and a second coupler having a circular-type main hole depressed at an end corresponding to the connection portion, and a spiral groove formed at an inner circumference of the main hole corresponding to the spiral rib. The connection portion and the spiral rib are relatively connected with the main hole and the spiral groove by being pressed, and transmit a rotation force by being rotated together.

Abstract: A coupling apparatus, a development cartridge, and an electrophotographic printer having the coupling apparatus. The coupling apparatus transfers a rotation force in a connected state. The coupling apparatus has a first coupler having a cylindrical-type connection portion at an end and a spiral rib spirally protruded at an outer circumference of the connection portion; and a second coupler having a circular-type main hole depressed at an end corresponding to the connection portion, and a spiral groove formed at an inner circumference of the main hole corresponding to the spiral rib. The connection portion and the spiral rib are relatively connected with the main hole and the spiral groove by being pressed, and transmit a rotation force by being rotated together.

Abstract: A coupling apparatus to transfer a rotation force in a connected state. The apparatus has a first coupler having a first sloping rib formed at one end thereof and sloped in a rotation direction, and a second coupler having a second sloping rib formed at an inner circumference of the second coupler and sloped to correspond to the first sloping rib. The sloping ribs are connected by being pressed as the first coupler and the second coupler are relatively rotated, and rotation axes of the couplers coincide when the sloping ribs are completely connected.