Abstract: A developing device configured to develop a latent image formed on an image bearing member includes a rotatable developing-agent bearing member configured to bear developing agent, a developing container configured to form a developing-agent storage chamber that stores the developing agent, a developing-agent regulating portion provided in the developing container to regulate an amount of the developing agent born on the developing-agent bearing member, a support portion configured to support the developing-agent bearing member movably relative to the developing-agent regulating portion, and a pressurizing member configured to pressurize the developing-agent bearing member toward the developing-agent regulating portion. A contact portion of the developing-agent regulating portion with the developing-agent bearing member is fixed to the developing container without forming a gap from the developing container on a downstream side in a pressurizing direction of the pressurizing member.

Abstract: An image forming apparatus includes a developing device including a developer carrying member, a developer supplying member and a regulating member; a first power source for the developer carrying member; a second power source for the regulating member; and a controller. In a period from a start of a developing operation to an end of the developing operation for a same recording material, the controller effects control of providing a potential difference between the developer carrying member and the developing blade so that a force for urging the developer from the regulating member toward the developer carrying member acts on the developer at a contact portion between the regulating member and the developer carrying member, the force acting on the developer being stronger at a time of the end of the developing operation than at a time of the start of the developing operation.

Abstract: A developing device including a containing unit configured to be arranged below a supply member and contain a developer and a developer bearing member configured to bear the developer and develop an electrostatic latent image, further includes a supply member which is configured to supply the developer to the developer bearing member, to be arranged to form a nip portion between the supply member and the developer bearing member, and to rotate in a direction in which its surface moves from an upper end to a lower end of the nip portion, and a conveyance member which is configured to convey the developer contained in the containing unit onto the supply member.

Abstract: A developing device including a containing unit configured to be arranged below a supply member and contain a developer and a developer bearing member configured to bear the developer and develop an electrostatic latent image, further includes a supply member which is configured to supply the developer to the developer bearing member, to be arranged to form a nip portion between the supply member and the developer bearing member, and to rotate in a direction in which its surface moves from an upper end to a lower end of the nip portion, and a conveyance member which is configured to convey the developer contained in the containing unit onto the supply member.

Abstract: An image forming apparatus has a photosensitive drum configured to bear a developer image, a developing apparatus having a developing roller that bears developer and a developing blade that regulates the amount of the developer on the developing roller, and a detection portion that detects information on the amount of the developer stored in the developing apparatus. The image forming apparatus performs a discharging operation for discharging a coating agent, applied to a developing roller in an unused state, from the developing apparatus to the photosensitive drum, while varying an operational condition for the discharging operation varied based on the information.

Abstract: An image forming operation for forming an image on one recording material includes a developing bias application unit applying a developing bias to a developer bearing member and a supply bias application unit applying a supply bias to a developer supply member. At the start of image formation, an absolute value of the developing bias is greater than an absolute value of the supply bias, and in a center or latter half of the image formation period, the developing bias and the supply bias have equal potential, and then the absolute value of the developing bias becomes smaller than the absolute value of the supply bias, until the end of image formation.

Abstract: An image forming apparatus includes a developer bearing member, a developing bias application unit, a developer supply member, and a supply bias application unit that applies a supply bias to the developer supply member. In a predetermined period before a start of image formation during an image forming operation for an image formed on one recording material, the supply bias application unit applies a supply bias of which the magnitude of an absolute value is smaller than that of a developing bias, to the developer supply member. In a period between the start of image formation and an end of image formation during the image forming operation, the supply bias application unit applies a supply bias to the developer supply member so that a difference in the magnitude of the absolute value from the supply bias in the predetermined period before the start of image formation increases gradually.

Abstract: An image forming apparatus configured to form an image with developer includes an image bearing member configured to bear an image of the developer, a developer carrying member configured to carry the developer to supply the developer to the image bearing member, and a developer supplying member configured to supply the developer to the developer carrying member. At least a part of a surface of the developer carrying member is coated with lubricant charged to the same polarity as the developer, and an absolute value of a charge amount per unit mass of the lubricant is larger than that of the developer. The image forming apparatus executes a first sequence of applying a potential difference between the developer supplying member and the developer carrying member before image formation to form an electric field to suppress movement of the charged lubricant from the developer carrying member to the developer supply member.

Abstract: An image forming apparatus includes a detachably mountable developing device including a developer container, a developer carrying member, a feeding member, provided in contact with the developer carrying member, for supplying the developer to the developer carrying member, and a developer regulator; and a voltage device capable of applying to the developer carrying member and the developer regulator respective voltages different from each other. The image forming apparatus carries out, when a fresh developing device is mounted, an initial operation in which the developer carrying member is rotated. In the initial operation, the voltage device applies, to at least one of the developer carrying member and the developer regulator, a voltage for the initial operation which is different from the voltage for normal image forming operation, so as to urge a material applied to the developer carrying member in the fresh developing device toward the developer regulator from the developer carrying member.

Abstract: In a developer container or the like, developer is conveyed efficiently by utilizing a projecting portion included in a transmitting member and another projecting portion. A velocity vector that is generated at a free end of a conveying member and is oriented upward becomes largest during a period from when the conveying member having been in contact with the projecting portion is released from the projecting portion until when the free end of the conveying member comes into contact with a storage chamber.

Abstract: In a development device in which a developer containing unit underlies a development chamber, a supplying member in the development chamber forms a nip portion with a developer carrier and the developer carrier and the supplying member rotate in the direction in which their respective surfaces move from an upper end to a lower end of the nip portion.

Abstract: A developing device configured to develop a latent image formed on an image bearing member includes a rotatable developing-agent bearing member configured to bear developing agent, a developing container configured to form a developing-agent storage chamber that stores the developing agent, a developing-agent regulating portion provided in the developing container to regulate an amount of the developing agent born on the developing-agent bearing member, a support portion configured to support the developing-agent bearing member movably relative to the developing-agent regulating portion, and a pressurizing member configured to pressurize the developing-agent bearing member toward the developing-agent regulating portion. A contact portion of the developing-agent regulating portion with the developing-agent bearing member is fixed to the developing container without forming a gap from the developing container on a downstream side in a pressurizing direction of the pressurizing member.

Abstract: A developing apparatus includes a developing container for accommodating a developer; a developer carrying member for carrying the developer to a developing zone for developing a latent image; a developer regulator in contact with the developer carrying member to regulate a developer layer thickness on the developer carrying member; a developer feeding member in contact with the developer carrying member to supply the developer to the developer carrying member; an urging member for urging the developer carrying member toward the developer regulator; and a moving mechanism for moving the developer carrying member in a first direction which is a direction in which the urging member urges the developer carrying member and in a second direction crossing with the first direction. The moving mechanism moves the developer carrying member in the second direction to reduce or remove press-contact forces applied by the developer regulator and the developer feeding member.

Abstract: A developing device configured to develop a latent image formed on an image bearing member includes a rotatable developing-agent bearing member configured to bear developing agent, a developing container configured to form a developing-agent storage chamber that stores the developing agent, a developing-agent regulating portion provided in the developing container to regulate an amount of the developing agent born on the developing-agent bearing member, a support portion configured to support the developing-agent bearing member movably relative to the developing-agent regulating portion, and a pressurizing member configured to pressurize the developing-agent bearing member toward the developing-agent regulating portion. A contact portion of the developing-agent regulating portion with the developing-agent bearing member is fixed to the developing container without forming a gap from the developing container on a downstream side in a pressurizing direction of the pressurizing member.

Abstract: In a predetermined period up to a start of image formation during an image forming operation for an image formed on one recording material, a supply bias application unit applies a supply bias of which the magnitude of an absolute value is smaller than that of a developing bias, to a developer supply member. In a period between the start of image formation and an end of image formation during the image forming operation for the image formed on one recording material, the supply bias application unit applies a supply bias to the developer supply member so that a difference in the magnitude of the absolute value from the supply bias in the predetermined period up to the start of image formation increases gradually.

Abstract: In a developer container or the like, developer is conveyed efficiently by utilizing a projecting portion included in a transmitting member and another projecting portion. A velocity vector that is generated at a free end of a conveying member and is oriented upward becomes largest during a period from when the conveying member having been in contact with the projecting portion is released from the projecting portion until when the free end of the conveying member comes into contact with a storage chamber.

Abstract: An image forming apparatus configured to form an image with developer, including: an image bearing member configured to bear an image of the developer; a developer carrying member configured to carry the developer to supply the developer to the image bearing member; and a developer supplying member configured to supply the developer to the developer carrying member, wherein at least a part of a surface of the developer carrying member is coated with lubricant charged to the same polarity as the developer, an absolute value of a charge amount per unit mass of the lubricant is larger than that of the developer, and the image forming apparatus executes a first sequence of applying a potential difference between the developer supplying member and the developer carrying member before image formation to form an electric field in a direction directing the lubricant from the developer supplying member toward the developer carrying member.

Abstract: During an image formation period from a start of image formation until an end of image formation in an image forming operation for forming an image on one recording material, a developing bias application unit applies a developing bias to a developer bearing member and a supply bias application unit applies a supply bias to a developer supply member, such that, at the start of image formation, the absolute value of the developing bias is greater than the absolute value of the supply bias, and in the exact center or the latter half of the image formation period, the developing bias and the supply bias have equal potential, whereupon the absolute value of the developing bias becomes smaller than the absolute value of the supply bias, until the end of image formation.

Abstract: An image forming apparatus includes a detachably mountable developing device including a developer container, a developer carrying member, a feeding member, provided in contact with the carrying member, for supplying the developer to the carrying member, and a developer regulator; and a voltage device capable of applying to the carrying member and the regulator respective voltages different from each other. The apparatus carries outs, when a fresh developing device is mounted, an initial operation in which the carrying member is rotated. In the initial operation, the voltage device applies, to at least one of the carrying member and the regulator, a voltage for the initial operation which is different from the voltage for normal image forming operation, so as to urge a material applied to the carrying member in the fresh developing device toward the regulator from the carrying member.

Abstract: An electrophotographic image forming apparatus includes an electrophotographic photosensitive member configured to bear an electrostatic latent image, and a developer carrying member configured to develop the electrostatic latent image. The electrophotographic photosensitive member and the developer carrying member are separated from each other during non-image formation and brought into contact with each other after the electrophotographic photosensitive member and the developer carrying member start to be rotated. During a time period between a time when the electrophotographic photosensitive member and the developer carrying member start to be rotated and a time when the electrophotographic photosensitive member and the developer carrying member are brought into contact with each other, a number of revolutions of the developer feed member is larger than a number of revolutions of the developer carrying member.