Abstract: A drive gear for a generally cylindrical imaging component. The drive gear includes a body for engaging the generally cylindrical imaging component; a cylindrical shaft attached to the body, the cylindrical shaft having an end surface; and three prongs extending longitudinally outward from the end surface.

Abstract: An image forming apparatus driving unit includes a rotatable member which is rotatably supported, a pair of bearing portions for rotatably supporting the rotatable member, and a motor for driving the rotatable member. In addition, a driving gear is provided on a driving shaft of the motor, and a driven gear, provided outside the pair of bearing portions with respect to a rotational axis direction of the rotatable member, engages with the driving gear to be rotated integrally with the rotatable member. At least one of the driven gear and the driving gear has, with respect to the rotational axis direction of the rotatable member, a crown shape so that a central tooth surface of a tooth projects more than end tooth surfaces of the tooth at a side where the driven gear and the driving gear engage each other.

Abstract: A drive gear for a generally cylindrical imaging component. The drive gear includes a body for engaging the generally cylindrical imaging component; a cylindrical shaft attached to the body, the cylindrical shaft having an end surface; and three prongs extending longitudinally outward from the end surface.

Abstract: An image forming apparatus include a door through which a tray carrying a cartridge passes, wherein in interrelation with the door closing operation, (i) movement of the tray from a movable position to an image forming position, (ii) movement of a drive transmission member, for transmitting a driving force to the cartridge from a main assembly, from a first spacing position to a drive-connecting position, (iii) movement of an urging member for urging the cartridge to the main assembly from a second spacing position to a contact position, and (iv) movement of an electric energy supply member, for supplying electric power to the cartridge from the main assembly, from a third spacing position to an electric energy supplying position, are carried out in the order named.

Abstract: A developing device includes a developer cartridge and a developing unit. The developing unit includes a first guide and a second guide. The second is movable with respect to the developing frame between a first position where the second guide is in continuous with the first guide and a second position where a continuous state of the second guide with the first guide is interrupted. The developer cartridge includes a developer frame that accommodates a developer and a first guided member movable with respect to the developer frame. The first guide and the second guide at the first position guide the first guided member in the course of attaching the developer cartridge to the developing unit. When an attachment of the developer cartridge to the developing unit completes, the first guide receives the first guided member, and the second guide is at the second position.

Abstract: 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.

Abstract: A driving force transmission mechanism comprising a photosensitive drum driving member, wherein the photosensitive drum driving member is engaged with an image forming apparatus driving member and receives the driving force from the image forming apparatus driving member; the image forming apparatus driving member comprises a triangular groove having a triangular cross-section and driving force transmission portion disposed in three vertex angles of the triangular groove; the photosensitive drum driving member comprises a non-distorting protrusion which is axially extended from the end face of a drum shaft and engaged with the groove on the image forming apparatus driving member; the protrusion has a position-limiting mechanism and a stressed mechanism; a projecting tooth obliquely disposed on said non-distorting protrusion is taken as the stressed mechanism; and each projecting tooth also has a mating surface which is engaged with the driving force transmission component to transmit the driving force.

Abstract: A bearing mechanism for connection with a photosensitive drum and an electronic imaging device includes a transmission member for coupling a rotary driving member of the electronic imaging device, a conductive piece at an inner portion of the transmission member, a conductive bar, and a spring member. The transmission member is synchronously rotatably mounted to the photosensitive drum and includes a through hole. The conductive bar is slidably mounted into the through hoe of the transmission member for electrically contacting a conductive shaft of the electronic imaging device. The spring member is electrically connected between the conductive piece and the conductive bar for providing a rebound force forcing the conductive bar to move away from the inner portion of the transmission member. In this way, the axial offset between the transmission member and the rotary driving member can be compensated.

Abstract: A driving force transmission unit includes on a driving force transmission path a first driving rotary body with a plurality of first contact portions, a first driven rotary body with a plurality of first contact targets, a second driving rotary body with a plurality of second contact portions, and a second driven rotary body with a plurality of second contact targets. Each of the plurality of the first contact portions and each of the plurality of the first contact targets are disposed such that peaks of periodical shock generated as a first connecting portion defined by one of the first contact portions contacting one of the first contact targets changes from one to another do not overlap with peaks of periodical shock generated as a second connecting portion defined by one of the second contact portions contacting one of the second contact targets changes from one to another.

Abstract: An image forming device comprises a device main body; a cartridge attachable to the device main body; a main body transmission unit to rotate about a first rotation axis; a main body joint unit to rotate about a second rotation axis allowed to intersect with the first rotation axis; a cartridge transmission unit configured to rotate about a third rotation axis and to transmit a driving force to a rotation body; and a cartridge joint unit to rotate about a fourth rotation axis allowed to intersect with the third rotation axis. The cartridge joint unit is further configured to rotate coaxially with respect to the main body joint unit and to rotate the cartridge transmission unit when the main body transmission unit rotates in a state where the cartridge is attached to the device main body and the cartridge joint unit is coupled to the main body joint unit.

Abstract: A coupling which may include a driving side member, a driven side member, and an intermediate member interposed between the driving side member and the driven side member. The intermediate member may be configured to transmit a driving force from the driving side member to the driven side member. The driven side member may include a first driven side rotating body having a first engaging portion and a second driven side rotating body having a second engaging portion. Further, the second driven side rotating body may be configured to rotate relative to the first driven side rotating body about a common axis of rotation with the first driven side rotating body. Additionally, the second engaging portion may be disposed outside of the first engaging portion with respect to a radial direction of the first driven side rotating body.

Abstract: An electrophotographic photoreceptor is used by being detachably mounted onto an apparatus main body of an electrophotographic application apparatus while being incorporated in a process cartridge. The electrophotographic photoreceptor has a photosensitive drum formed by forming a photosensitive layer containing a photoconductive material on an outer circumferential surface of a cylindrical conductive substrate; and a flange that is fitted to an open end of the photosensitive drum and transmits a rotational driving force from the apparatus main body to the photosensitive drum. In the flange, on a surface thereof receiving the rotational driving force, a driven-side power transmission portion that is configured by a cylindrical body disposed concentrically with respect to a central shaft of the photosensitive drum, and engaging projections are provided.

Abstract: An image forming apparatus configured to form a toner image on a sheet, including: a transfer belt configured to bear and transfer the toner image to the sheet conveyed at given conveying speed; a drive roller configured to drive the transfer belt; a speed detection roller held in contact with the transfer belt and configured to output roller information on rotational speed of the speed detection roller when the speed detection roller rotates as the transfer belt runs; a motor configured to drive the drive roller; a motor speed output portion configured to output motor information on rotational speed of the motor; and a control element configured to control the rotational speed of the motor.

Abstract: An image forming apparatus including, a photosensitive body for carrying toner images, a transfer section for nipping the recording sheet at a position facing the photosensitive body and transferring the toner images carried on the photosensitive body onto a recording sheet, a driving section for driving the photosensitive body, and a control section for giving instructions to the driving section to conduct a velocity control to rotate the photosensitive body at a predetermined velocity, wherein the control section sets a gain of velocity control to be greater than normal condition, at a time which is at least one of a time when the recording sheet enters the transfer section, or a time when the recording sheet separates from the transfer section.

Abstract: An image forming apparatus including a process cartridge having a developing device and detachably installable in the image forming apparatus, and a drive unit to rotatively drive the developing device. The drive unit includes a drive force generator to generate a drive force to rotatively drive the developing device, a drive substrate to support the drive force generator, a drive shaft to transmit the drive force to the developing device, a bracket having a cylindrical bearing seating, a bracket bearing provided inside the bearing seating to support the drive shaft in a thrust direction, and an elastic member provided between the bearing seating and the bracket bearing to allow movement of the drive shaft in a radial direction, and a substrate bearing provided to the drive substrate to support the drive shaft in both the radial and thrust directions.

Abstract: An electrophotographic photosensitive drum comprises a cylinder having a photosensitive layer formed thereon, with the cylinder being rotatable about an axis thereof. A driving force transmitting part is securely fixed to one axial end of the cylinder. The driving force transmitting part includes (i) a gear encircling a peripheral portion of the driving force transmitting part and (ii) a projection disposed on a side of the gear opposite from the cylinder, with the projection having a base and a free end. At least a portion of a cross-section of the projection at the base is offset from a corresponding portion of a cross-section of the projection at the free end, as seen in a direction of the axis.

Abstract: Provided is a driving force transmission device including a sun gear that rotates by receiving a driving force from a driving source, an internal gear that is arranged coaxially with the sun gear, a planetary gear that engages with the sun gear and the internal gear, a rotary member that is provided coaxially with the sun gear and the internal gear and installed with the planetary gear so as to rotate corresponding to revolution of the planetary gear, and an urging member that urges the planetary gear toward the rotary member.

Abstract: A drive gear for a generally cylindrical imaging component. The drive gear includes a body for engaging the generally cylindrical imaging component; a cylindrical shaft attached to the body, the cylindrical shaft having an end surface; and three prongs extending longitudinally outward from the end surface.

Abstract: An image forming apparatus is provided that may include a photosensitive drum configured to rotate around an axis and a first rotational member disposed proximate a periphery of the photosensitive drum and configured to rotate about an axis parallel to the rotational axis of the photosensitive drum. The image forming apparatus may also include a driving-force transmitting member and a driven member, which includes a transmitted portion and a first engaging projection. The driven member may rotate about the rotational axis of the photosensitive drum together with the photosensitive drum and the transmitted portion of the driven member may receive a driving force transmitted from the driving-force transmitting member. The image forming apparatus may also include a rotational-member driving gear which has a loose fit portion configured to engage with the first engaging projection and a transmission gear portion configured to transmit the driving force to the first rotational member.

Abstract: A toner drum gear flange socket adapted for engagement with a force transmitting end of a drive shaft in an electrophotographic image forming apparatus. The socket includes a bottom wall and an outer cylindrical wall including an inner surface and defining a central axis. Circumferentially spaced apart curved base wall portions extend axially from the bottom wall. Each base wall portion includes an enlarged end portion that defines a radially inwardly extending projection. A leg wall portion extends radially from one end of each curved base wall portion. Each leg wall portion defines an elongated contact surface. The radially inwardly extending projections secure the force transmitting end of the drive shaft within the socket, and the elongated contact surfaces receive driving rotational force from the force transmitting end of the drive shaft.

Abstract: An image forming apparatus includes a body, an image carrier provided in the body and configured to form an image thereon, a first gear to transmit a rotation driving force to the image carrier, a first rotary shaft to which the image carrier and the first gear are attached, a second gear to mesh with the first gear and transmit the rotation driving force to the first gear, a second rotary shaft to which the second gear is attached, a drive source configured to drive to rotate the image carrier via the first gear and the second gear, a first holder to hold the first rotary shaft of the first gear, and a second holder to hold the second rotary shaft of the second gear, and a relative position between the first holder and the second holder therein is adjustable.

Abstract: An image forming apparatus may transfer an image to a transfer-receiving material. The image forming apparatus includes a main body to which a cartridge is detachably mounted. The cartridge includes an image bearing member in contact with the transfer-receiving material and a receiving member to receive driving force from the main body to drive and rotate the image bearing member. The image forming apparatus also includes a shaft passing through and supporting the receiving member of the cartridge and a transmission member to rotate around the shaft and to transmit drive force from a motor to the receiving member. A bending unit included with the image forming apparatus bends the shaft passing through and supporting the receiving member and the transmission member.

Abstract: An image forming apparatus includes a unit housed in an apparatus body and configured to contribute to image formation, a driving source disposed in the apparatus body and configured to apply a driving force to the unit, an opening formed in the apparatus body, a door configured to form a conveyance path for conveying a recording material, and movable between a first position, where the opening is closed, and a second position, where the opening is opened, and a transmission unit configured to transmit the driving force from the driving source to the unit when the door is at the first position and to urge the door in a door closing direction.

Abstract: An image forming apparatus capable of achieving improved image quality even when image formation is performed using a plurality of types of drive sources different in characteristics. Image forming units for colors form toner images of the respective colors on respective photosensitive drums each of which is driven by a DC motor for rotation. Encoder sensors detect information on the rotational speed of the photosensitive drums. An image forming unit for black forms a black toner image on a photosensitive drum having an outer diameter larger than that of the photosensitive drums for colors, which is driven by a stepper motor for rotation. An intermediate transfer belt transfers toner images formed on the respective photosensitive drums to a sheet. A motor controller controls a drive frequency of the stepper motor based on information on the rotational speed of the photosensitive drum for black.

Abstract: An image forming apparatus, including an image forming unit; a resin-made frame to support the image forming unit; a drive source arranged on a one-end side of a transmission path to generate driving force; a gear arranged on the other-end side of the transmission path to be rotated, while one of axial ends of a shaft of the gear is supported by the frame; a metal-made first supporting member fixed to the frame to support the other of axial ends of the shaft of the gear thereon; a metal-made second supporting member fixed to the frame to support the drive source thereon and; an endless belt; a first pulley supported by the second supporting member to transmit the driving force to the endless belt, the first pulley being; and a second pulley having the endless belt strained there-around and supported by the first supporting member, is provided.

Abstract: An image formation apparatus includes: an image formation unit including an image carrier configured to carry a developer image; a drive unit configured to drive the image carrier; a holder provided with the drive unit; a transfer unit located to be opposed to the image carrier and configured to transfer the developer image from the image carrier on a transfer medium; and a switching unit configured to switch a position of the holder between an image formation position, at which the transfer unit transfers the developer image from the image carrier on the transfer medium, and a non-image formation position. The holder is configured to move together with the image formation unit.

Abstract: A drive transmission device includes drive transmission members including a detection target gear, a detection device detecting the rotational position of the target gear and including a position detection member and a detection unit, and a conductive protection member protecting the detection unit. The detection unit and the protection member are assembled to the same member to be installed to an external apparatus. If there is a dimensional error in the protection member causing a portion of the protection member closest to the target gear to shift in position relative to the detection unit beyond a predetermined range, the protection member comes into contact with the detection unit in the assembling process, and is corrected in shape by the detection unit, with the shift in position relative to the detection unit of the portion of the protection member closest to the target gear kept within the predetermined range.

Abstract: An image forming apparatus cartridge includes a casing and a developer roller having an axis L1, with the developer roller being rotatably supported in the casing to permit rotation about the axis L1. The cartridge also includes a first gear connected to the developer roller and a second gear in meshing engagement with the first gear. The cartridge further includes a coupling member having an axis L2, with the coupling member having (i) a first end portion connected to the second gear and operatively connected with the developer roller so as to be capable of transmitting a rotational force to the developer roller via the first and second gears, (ii) a second end portion having a recess formed therein and including at least two projections provided at diametrically opposed positions, and (iii) a connecting portion connecting the first end portion and the second end portion.

Abstract: A process cartridge is detachably mountable to a main assembly of an electrophotographic image forming apparatus. The process cartridge includes a coupling member provided at an axial end portion of a photosensitive drum and rotatable about a coupling axis thereof so as to transmit a driving force to the photosensitive drum. The coupling member is capable of inclining relative to the photosensitive drum so that the coupling axis inclines relative to a drum axis, with the coupling member having a first end portion connected to the photosensitive drum, a second end portion, and a connecting portion between the first end portion and the second end portion. A maximum distance from the coupling axis to an outermost surface of the connecting portion along a line perpendicular to the coupling axis is less than a maximum distance from the coupling axis to an outermost surface of the second end portion along a line perpendicular to the coupling axis.

Abstract: A cartridge detachably mountable to a main assembly of an image forming apparatus, the main assembly including a main assembly electrical contact, includes a roller including an electroconductive shaft, the roller being rotatable with the shaft; and a supporting member rotatably supporting the shaft and provided with a hole portion for exposing a part of a surface of a longitudinal end of the shaft to directly contact the part to the main assembly electrical contact and an end surface positioning portion for determining a position of the end surface with respect to a longitudinal direction of the shaft by contacting another part of the end surface.

Abstract: An image forming apparatus includes a main body including an image forming unit including an image carrying member, a drive force transmission mechanism configured to transmit a drive force to the image carrying member, and a main body configured to support the image forming unit. The main body includes a first frame disposed on a first side of the image carrying member in an axial direction of the image carrying member, a second frame disposed on a second side of the image carrying member opposite to the first side thereof, a first connecting member extending in the axial direction of the image carrying member and connecting the first frame and the second frame, and a second connecting member spaced apart from the first connecting member and connecting the first frame and the second frame. The first frame is made of metal and the second frame is made of resin.

Abstract: An image forming apparatus having: a rotating member adapted to support an image; a first drive source configured to generate a drive force; a transmission mechanism configured to transmit the generated drive force toward the rotating member, the mechanism including an upstream gear and a downstream gear configured to receive the drive force therefrom; a sensor configured to output a signal indicating a rotational status of the rotating member; a control circuit configured to generate a control signal appropriate for non-uniform rotation of the rotating member, on the basis of the signal outputted by the sensor; and an actuator configured to cause a rotation axis of the first drive source or the transmission mechanism to pivot, in accordance with the control signal, thereby changing a force with which the upstream gear pushes the downstream gear into rotation such that the non-uniform rotation is cancelled out.

Abstract: An electrophotographic photosensitive drum unit includes (a) a cylinder having a photosensitive layer at an outer periphery thereof and (b) a drum flange provided at one end of the cylinder, with the drum flange including at least two projections provided inside of the drum flange and projected radially inwardly of the drum flange, and with a space diametrically between the two projections. Each of the two projections projects radially inwardly of the drum flange to a greater extent at a position farther from the cylinder than it does at a position closer to the cylinder.

Abstract: There is provided a torque transmitting member that appropriately maintains conductivity between an image forming apparatus body and a photosensitive drum and can suppress the occurrence of conduction failure. A torque transmitting member, which is disposed at an end portion of a photosensitive drum unit and transmits torque, includes: an cylindrical end member that includes a bearing portion at one end portion thereof and a fitting portion, which is inserted into a photosensitive drum, at the other end portion thereof; and a conductive conducting shaft member that is disposed so as to extend along a cylindrical shaft of the end member and includes a conductive material, which is elastically deformed, on at least a part thereof.

Abstract: An image forming apparatus including: a photoreceptor for bearing a toner image; a transfer body onto which the toner image borne by the photoreceptor is transferred; a drive section for driving the photoreceptor and transfer body respectively, and a control section for controlling the drive section so as to drive the photoreceptor and transfer body at a predetermined driving speed, wherein the control section, under a state in which the control section controls to drive the transfer body at the predetermined driving speed, controls to: a) drive the photoreceptor while changing the driving speed of the photoreceptor within a range of driving speeds between low speed and high speed, including the predetermined driving speed, b) extract torque characteristics under the control which includes the change of driving speed of the photoreceptor, and c) determine the driving speed of the photoreceptor based on the extracted torque characteristics.

Abstract: A gear drive apparatus includes a gear train including a plurality of gears, and a holding unit accommodating the gear train and a lubricant to be supplied to tooth flanks of each of the plurality of gears, the holding unit including an inlet opening from which the lubricant is poured. The lubricant from the inlet opening is supplied to an engagement area where two gears of the plurality of gears are engaged with each other, or to a tooth flank area of one of the two gears at an upstream part from the engagement area along a rotational direction of the one of the two gears.

Abstract: A driving device includes a motor, a pulley, a metal belt, a first unit, a second unit, a biasing member and a detector. The motor includes a drive shaft. The pulley includes an output shaft extending in parallel to the drive shaft. The pulley is rotatably supported on the first unit with the output shaft as a rotary shaft and the circumferential surface is arranged at a distance from the drive shaft in a radial direction of the rotation. The second unit supports the motor and is slidable relative to the first unit. The biasing member biases the second unit in a direction to move the drive shaft away from the output shaft in a state where the metal belt is mounted between the drive shaft and the pulley. The detector detects a change in an inter-axial distance between the drive shaft and the output shaft.

Abstract: A rotating-body driving device comprising: a rotating body; a driving source; a reduction gear that includes an output shaft and a gear rotating at a non-integer ratio of rotation period to a rotation period of the output shaft, and the reduction gear reducing rotation speed of the driving source; a pulse-signal generating unit; a pulse-count storage unit; a speed-fluctuation storage unit that stores therein a rotation speed fluctuation of the output shaft; and a driving-source control unit, wherein the driving-source control unit detects the speed fluctuation information associated with the accumulated number of pulse signals from the speed-fluctuation storage unit, and performs for the driving source a feedforward control to set off the rotation speed fluctuation.

Abstract: An electric motor and a control unit are juxtaposed in a speed reduction gear box. A terminal block is provided at an outer circumference of a flange proximate to a control unit of the electric motor. Terminal block surfaces of the terminal block are provided so that a plane direction faces a direction vertical to a shaft line of the electric motor. A motor side connecting terminal is held on the terminal block surface. The unit side connecting terminals provided at a position proximate to the electric motor of the control unit are arranged so as to overlap with the motor side connecting terminal on the terminal block surface to couple by a coupling portion (fixing screw).

Abstract: An image forming apparatus is provided, which includes a controller configured to switch a circumferential velocity of a development roller from a second circumferential velocity to a first circumferential velocity no later than when development of a photoconductive drum is started and to switch the circumferential velocity of the development roller from the first circumferential velocity to the second circumferential velocity after the development of the photoconductive drum is completed.

Abstract: A cartridge includes a casing, a rotatable member rotatably supported by the casing, a protruding member configured to advance and retract in directions parallel to an axis of rotation of the rotatable member, and an urging member configured to urge the protruding member to advance in an advancing direction. The protruding member has a particular sloping surface configured to be contacted in a direction orthogonal to an axis of rotation of the protruding member when the cartridge is mounted. The particular sloping surface slopes with respect to directions parallel to and orthogonal to the axis of rotation of the protruding member.

Abstract: A bearing member engageable and disengageable from a recessed portion of an image forming apparatus body is included. While the bearing member is engaged into the recessed portion, a cross-sectional area occupancy ratio which is a degree of area occupied by a cross-section of the bearing member to a cross-section of the recessed portion is 15% or higher and 75% or less. An outer peripheral shape of the bearing member in a cross-section is a hexagon, and assuming that a radius of a circumscribed circle of the hexagon is r1g, and when a hexagon is formed by sides enclosed by a triangle formed at an opening of the recessed portion when the recessed portion is viewed from a front in the axial direction and a triangle formed at a bottom of the recessed portion, a radius of an inscribed circle of the hexagon is r2h, r1g?r2h>0.

Abstract: A photosensitive drum includes a cylindrical photoreceptor, a drum gear located at one end of the photoreceptor, a drum shaft extending axially along the photoreceptor from one end of the drum gear for rotatably supporting the photoreceptor, and a projecting member extending longitudinally along the photoreceptor from an end surface of the drum shaft for coupling a twisted surface of a corresponding twisted triangular groove on a driving head of an imaging device. The projecting member, which is provided at one end of the photoreceptor, is operable to reciprocate along the longitudinal direction of the photoreceptor with respect to the photoreceptor. As a result, the photosensitive drum is prevented from being ejected from the driving head of the imaging device during force transmission between them, while maintaining a stable transmission of driving force between the photosensitive drum and the imaging device. A process cartridge carries the photosensitive drum.

Abstract: An image forming apparatus includes an image holding body unit having a first supported portion and an image holding body that is rotated while holding an image on a surface of the image holding body; and a conveying unit that is disposed below the image holding body unit and has conveying members for conveying a medium on which the image formed on the surface of the image holding body is to be recorded, image holding body support portions that supports both end portions, in an axial direction, of the image holding body, and a first support portion that supports the first supported portion.

Abstract: An image forming apparatus may include one or more photosensitive media, a driving unit to rotate the photosensitive media, a detecting unit to detect a rotational state of each of the photosensitive media and a controller to control the driving unit based on the rotational state detected by the detecting unit so that two adjacent photosensitive media stop with a phase angle difference between them that is capable of compensating for image registration errors.

Abstract: A heating device including a heating member that heats a recording medium; a pressure unit that applies pressure to the heating member; and a rotation member that is mounted to the heating member. The rotation member is rotated upon receiving an external force and the heating member is rotated along with a rotation of the rotation member by a frictional force between the heating member and the rotation member.

Abstract: A cartridge includes a developing roller, supply roller, input rotary body, developing roller rotary body, and supply roller rotary body. The developing roller/supply roller rotary bodies transmit the drive force inputted from the input rotary body to the developing roller/supply roller, respectively. The developing roller rotary body includes first and second drive input parts having different diameters. The input rotary body includes first and second drive output parts engaged with the first and second drive input part, respectively and having different diameters. The first drive output part is movable between a first position and second position. The first drive input part and the first drive output part are engaged when the first drive output part is in the first position. The second drive input part and the second drive output part are engaged when the first drive output part is in the second position.

Abstract: The present invention provides a driving force transmission mechanism for an image forming apparatus and a process cartridge. The transmission mechanism includes a photosensitive drum driving component (10) and an image forming apparatus driving head (20). The driving component (10) includes a drum shaft (3) which axially projects from an end of a photosensitive drum (1) and a boss (4) which axially projects from an end surface of the drum shaft (3). A tooth (5a) is obliquely arranged on a side wall (4b) of the boss and projects in a radial direction. The driving head (20) includes a recess (11) with a twisted-surface and matching with the boss (4), the recess has a polygonal cross section with a twisted corner section. The process cartridge includes the driving component. The photosensitive drum driving component is easy to manufacture and is not easy to be damaged when using for a long time.

Abstract: A drive transmission device includes a first coupling member to be coupled to a drive shaft and including a first contact surface, a second coupling member to be coupled to a driven shaft and including a second contact surface, and an intermediate coupler disposed between the first and second coupling members. The intermediate coupler includes: a first intermediate contact surface opposed to the first contact surface and contacting the first contact surface with a first rolling member interposed in between; and a second intermediate contact surface opposed to the second contact surface and contacting the second contact surface with a second rolling member interposed in between. One of the contact surfaces and a corresponding one of the intermediate contact surfaces are formed point-symmetrically with respect to the center of a corresponding one of the rolling members.

Abstract: A photosensitive drum cartridge and an image forming apparatus including the photosensitive drum cartridge are provided. The photosensitive drum cartridge includes: a photosensitive drum; a primary cleaning roller which is configured to contact a surface of the photosensitive drum to remove an attached matter on the surface of the photosensitive drum; a first gear which is configured to rotate together with the photosensitive drum; a second gear which is configured to rotate together with the primary cleaning roller; and a third gear which is configured to mesh with the first gear and the second gear, and which has a rotation axis, a position of which is fixed such that a distance from a rotation axis of the first gear is constant.