Abstract: A solid-fuel burner includes: a venturi having a constricting portion where the transverse cross section of a fuel passage is reduced in a fuel nozzle for supplying a solid fuel; and a fuel concentrator for diverting the flow in the nozzle outward in the wake side of the venturi, and the nozzle is formed so that (a) the aperture in the vicinity of an opening portion of a boiler furnace wall surface has a flat shape, (b) cross-sectional shape thereof orthogonal to a nozzle center axis C on the outer peripheral wall of the nozzle is circular in a transverse cross section up to the constricting portion of the venturi, (c) a portion that has a gradually increasing degree of flatness is provided between the constricting portion and the opening portion, and (d) the flat shape in the opening portion is where the degree of flatness reaches a maximum.

Abstract: A boiler operating method operates a boiler by switching between air combustion mode and oxygen combustion mode when burning fossil fuel with first combustion gas and second combustion gas. The second combustion gas compensates for oxygen deficiency in the first combustion gas. The air combustion mode uses air as the first combustion gas and the second combustion gas while the oxygen combustion mode uses mixed gas of combustion flue gas and oxygen-rich gas as the first combustion gas and the second combustion gas, the combustion flue gas being produced when the fossil fuel is burned. By mixing the oxygen-rich gas in the air in the process of switching between air combustion mode and oxygen combustion mode, the air being the first combustion gas used in the air combustion mode, the boiler operating method can switch between the air combustion mode and oxygen combustion mode while maintaining stable combustion.

Abstract: An image forming apparatus of the present invention includes a developing device. In a case body of the developing device, a first storage chamber and a second storage chamber are formed. A first agitating screw is provided in the first storage chamber and a second agitating screw is provided in the second storage chamber. A developing roller is provided in the second storage chamber. A control portion controls driving of a first motor and a second motor. When toner installation is performed, the control portion controls driving of the first motor at a rotational speed higher than a rotational speed for development operation in a state where the second motor is stopped. When a certain condition is satisfied, the control portion starts control of driving of the second motor, to drive rotation of the second motor.

Abstract: A developing device includes a housing, a developer carrier, a conveying member and a surface layer. The conveying member conveys the developer in the first conveying direction and supplies the developer to the developer carrier. The surface layer is arranged on the circumferential surface of the developer carrier and formed on a surface of a predetermined cylindrical base member. The surface layer is formed by an immersion method of immersing the base member in an immersion tank so that an axial direction of the base member extends along a vertical direction. A lower end side of the base member at the time of the immersion is arranged in a downstream side of the housing in the first conveying direction and an upper end side of the base member at the time of the immersion is arranged in an upstream side of the housing in the first conveying direction.

Abstract: In accordance with the flow distribution of combustion gas including an unburned portion, an after-air port (AAP) arranged downstream of the two-stage combustion burner can effectively reduce the unburned portion by dividing as appropriate so as to avoid interaction, and by mixing together, two types of after-air having functions of linearity and spreading. As the configuration of this AAP, a primary nozzle for supplying primary after-air and having a vertical height greater than the horizontal width is provided in the center in the opening of the AAP, a secondary nozzle for supplying secondary after-air is provided in the opening outside of the primary nozzle, and one or more secondary after-air guide vanes having a fixed or variable tilt angle relative to the after-air port center axis are provided at the outlet of the said secondary nozzle to deflect and supply the secondary after-air horizontally to the left or right.

Abstract: An image forming apparatus of the present invention includes a developing device. In a case body of the developing device, a first storage chamber and a second storage chamber are formed. A first agitating screw is provided in the first storage chamber and a second agitating screw is provided in the second storage chamber. A developing roller is provided in the second storage chamber. A control portion controls driving of a first motor and a second motor. When toner installation is performed, the control portion controls driving of the first motor at a rotational speed higher than a rotational speed for development operation in a state where the second motor is stopped. When a certain condition is satisfied, the control portion starts control of driving of the second motor, to drive rotation of the second motor.

Abstract: A developer conveying apparatus includes a developer housing portion, a first spiral feeder, a second spiral feeder, a driving unit, an operation control unit, and a sensor. The first spiral feeder and the second spiral feeder each include a hollow spiral member and rib members. The hollow spiral member is spirally formed and internally has a space. The rib members run in a first direction and bridge spiral pieces constituting the spiral member. The operation control unit causes: the driving unit to change the rotation speed of the first spiral feeder and the second spiral feeder according to a printing linear speed of an image forming part; and the driving unit to change a rotational phase difference between the first spiral feeder and the second spiral feeder referring positions of the rib members to a predetermined rotational phase difference according to the changed rotation speed.

Abstract: A developing device includes a developing roller, a developer supply path, a developer conveyance path, a supply-side conveying member and an agitating-side conveying member. The developing roller is rotatably supported in the housing. The developer supply path is arranged along the developing roller. The developer conveyance path is arranged along the developer supply path. The supply-side conveying member is a conveying member arranged in the developer supply path and includes a first receiving portion arranged to face the communication path at an upstream side in the first direction and configured to receive the developer from the developer conveyance path, and has a hollow spiral shape at a side downstream of the first receiving portion. The agitating-side conveying member is a conveying member arranged in the developer conveyance path and includes a first transferring portion arranged to face the first receiving portion at a downstream side in the second direction.

Abstract: A developing device includes a housing, a developer carrier, a conveying member and a surface layer. The conveying member conveys the developer in the first conveying direction and supplies the developer to the developer carrier. The surface layer is arranged on the circumferential surface of the developer carrier and formed on a surface of a predetermined cylindrical base member. The surface layer is formed by an immersion method of immersing the base member in an immersion tank so that an axial direction of the base member extends along a vertical direction. A lower end side of the base member at the time of the immersion is arranged in a downstream side of the housing in the first conveying direction and an upper end side of the base member at the time of the immersion is arranged in an upstream side of the housing in the first conveying direction.

Abstract: A developer conveying apparatus includes a developer housing portion, a first spiral feeder, a second spiral feeder, a driving unit, an operation control unit, and a sensor. The first spiral feeder and the second spiral feeder each include a hollow spiral member and rib members. The hollow spiral member is spirally formed and internally has a space. The rib members run in the first direction and bridge spiral pieces constituting the spiral member. The operation control unit causes: the driving unit to change the rotation speed of the first spiral feeder and the second spiral feeder according to a printing linear speed of an image forming part; and the driving unit to change a rotational phase difference between the first spiral feeder and the second spiral feeder referring positions of the rib members to a predetermined rotational phase difference according to the changed rotation speed.

Abstract: A developing device includes a housing, a developing roller, a developer supply path, a developer conveyance path, a supply-side conveying member, an agitating side conveying member and first projection members. The developing roller is rotatably supported in the housing. The supply-side conveying member includes a supply-side spiral member formed by connecting spiral pieces, in the first direction and having a hollow interior formed by the connected spiral pieces and a first rib member extending in the first direction, is arranged in the developer supply path and conveys the developer in the first direction by being driven and rotated. The first projecting members extend in the first direction along an outer wall portion of the first rib member from a first area where the supply-side spiral member and the first rib member intersect and project radially outward in the rotation of the supply-side conveying member.

Abstract: A conveyance device includes a housing, a formation member, and a detection section. The housing has a first conveyance path, a second conveyance path, and a first communication path. The first and second conveyance paths each are a conveyance path for conveying a developer. The first communication path allows a first end portion of the first conveyance path and a first end portion of the second conveyance path to be in communication with each other via a communication surface. The communication surface has a first region and a second region. The formation member forms the second region of the communication surface so that a height of the second region from a bottom portion of the first communication path is lower than a height of the first region from the bottom portion of the first communication path. The detection section detects the amount of the developer.

Abstract: A developing device includes a first agitating member and a second agitating member. Each of the first and second agitating members includes a screw having a helical portion formed helically so as to define a hollow portion, and a plurality of ribs formed on the helical portion in the longitudinal direction of the screw. On at least one of the first and second agitating members, there is disposed a paddle opposed to the communicating portion on a downstream side in a transport direction of the developing powder. The paddle has a flat surface in a direction perpendicular to the longitudinal direction, and a width of a distal end of the paddle is smaller than a width of a proximal end of the paddle disposed to the agitating member in a plan view.

Abstract: A developing device includes a developing roller. The developing roller includes a magnetic roller configured to have multiple magnetic poles in a circumferential direction thereof and a roller-shaped developing sleeve sheathed on the magnetic roller, and supplies magnetic toner to a photosensitive drum. Further, the developing sleeve is configured such that a surface of an image region thereof, which is located in an intermediate portion thereof in a rotation axis direction thereof and which supplies the magnetic toner to the photosensitive drum, is coated with a non-magnetic material, and such that surfaces of non-image regions thereof, which are located at opposite ends thereof in the rotation axis direction and which supply no magnetic toner to the photosensitive drum, are coated with a magnetic material.

Abstract: A solid-fuel burner includes: a venturi having a constricting portion where the transverse cross section of a fuel passage is reduced in a fuel nozzle for supplying a solid fuel; and a fuel concentrator for diverting the flow in the nozzle outward in the wake side of the venturi, and the nozzle is formed so that (a) the aperture in the vicinity of an opening portion of a boiler furnace wall surface has a flat shape, (b) cross-sectional shape thereof orthogonal to a nozzle center axis C on the outer peripheral wall of the nozzle is circular in a transverse cross section up to the constricting portion of the venturi, (c) a portion that has a gradually increasing degree of flatness is provided between the constricting portion and the opening portion, and (d) the flat shape in the opening portion is where the degree of flatness reaches a maximum.

Abstract: A developer conveyance device includes a housing and a conveyance member. The conveyance member is supported to the housing and rotates to convey developer. The conveyance member includes a shaft portion, a helical member, and a plurality of reinforcement members. The plurality of reinforcement members are disposed in a circumferential direction of rotation of the conveyance member.

Abstract: A developer conveying device includes a housing with a pair of wall portions, a developer conveyance path extending between the pair of wall portions, and a conveying member. The conveying member is rotatably supported on the wall portions and conveys developer from one wall portion to the other. This conveying member includes a spiral member, shaft portions and a breaking member. The spiral member is formed by connecting spiral pieces, each forming one spiral turn, in a conveying direction of the developer and includes a hollow interior defined by the connected spiral pieces. The shaft portions are arranged at opposite end parts of the spiral member and rotatably supported on the wall portions and serve as a rotary shaft for the rotation of the conveying member. The breaking member extends across the hollow interior in a direction intersecting with the conveying direction.

Abstract: A developing device includes a developing roller. The developing roller includes a magnetic roller configured to have multiple magnetic poles in a circumferential direction thereof and a roller-shaped developing sleeve sheathed on the magnetic roller, and supplies magnetic toner to a photosensitive drum. Further, the developing sleeve is configured such that a surface of an image region thereof, which is located in an intermediate portion thereof in a rotation axis direction thereof and which supplies the magnetic toner to the photosensitive drum, is coated with a non-magnetic material, and such that surfaces of non-image regions thereof, which are located at opposite ends thereof in the rotation axis direction and which supply no magnetic toner to the photosensitive drum, are coated with a magnetic material.

Abstract: A developer conveying device includes a housing, a developer conveyance path and a conveying member. The developer conveyance path extends between the pair of wall portions of the housing. The conveying member conveys developer from one wall portion toward the other. The conveying member includes a spiral member, shaft portions, a rib member, a supporting member and a projecting portion. The spiral member is formed by connecting spiral pieces in a conveying direction of the developer and includes a hollow interior formed by the connected spiral pieces. The rib member extends in the conveying direction and bridges adjacent ones of the spiral pieces of the spiral member. The supporting member connects an end part of the rib member in the conveying direction and the shaft portion. The projecting portion projects from the end part of the rib member more toward the wall portion than the supporting member.

Abstract: A developing device includes a developing container, a first agitating/conveying member, a second agitating/conveying member, a developer supply member, a supply port, and a supply section. The developing container is separated into a developer supply passage, a first conveying chamber, and a second conveying chamber, which are arranged substantially parallel to one another. The supply section is disposed between the developer supply passage and the first conveying chamber, and through the supply section, the developer is supplied from the developer supply passage into the first conveying chamber.