Abstract: A powder supply device that includes a powder reservoir including a rotator having a rotation shaft, to store powder supplied from a powder container; and a powder amount detector. The powder amount detector includes a detected member disposed in the powder reservoir, a contact member attached to the rotation shaft, to contact the detected member to vibrate or move the detected member, a detector to detect vibration or a displacement of the detected member, and a detection result processor to detect the amount of the powder in the powder reservoir based on detection by the detector. The powder supply device further includes a controller to supply the powder from the powder container to the powder reservoir based on detection by the powder amount detector. The controller rotates the rotator in discharging the powder from the powder reservoir and supplying the powder from the powder container to the powder reservoir.

Abstract: A powder detection device includes a detection mechanism including an oscillation unit and a vibrated member, a vibrating member, and a detection unit. The oscillation unit outputs a signal having a frequency according to a state of a magnetic flux passing a space facing the oscillation unit. The vibrated member affecting the magnetic flux and disposed inside a container to face the oscillation unit via the container is vibrated by the vibrating member in a direction of facing the oscillation unit. The detection unit acquires frequency information of the signal at predetermined periods, determines presence/absence of an error of the detection mechanism based on error information associating a type of the error with a state of the signal, detects vibration of the vibrated member based on a change in the frequency information, and detects a remaining amount of powder in the container based on the detected vibration.

Abstract: A sheet size detector to detect a sheet size of a recording medium includes a movable member to move in a sheet size detection direction to a position corresponding to the sheet size, a magnetic flux detector including a coil disposed on a board face parallel to the sheet size detection direction to generate a magnetic flux in a direction perpendicular to the board face, and a target to oppose the board face and including a material to affect the magnetic flux. The target is different in configuration in the sheet size detection direction to change the magnetic flux in the direction perpendicular to the board face as the movable member moves. The magnetic flux detector outputs a signal corresponding to changes in magnetic flux in the direction perpendicular to the board face, and the signal corresponds to the position of the movable member.

Abstract: A sheet material thickness detection device includes a guide member, a non-rotating pressing member, a sensor, and a calculator. The guide member guides one side of a sheet material being conveyed. The pressing member presses the sheet material against the guide member in a manner displaceable in accordance with the thickness of the sheet material. The sensor is configured to magnetically or electrically detect a displaced amount of the pressing member that is displaced in accordance with the thickness of the sheet material. The calculator is configured to calculate the thickness of the sheet material based on an output signal of the sensor.

Abstract: A fluid detection apparatus to detect quantity of a fluid having flowability and stored in a casing includes an oscillator disposed outside the casing to output a frequency of an oscillation signal corresponding to a magnetic flux passing through a space near the oscillator, a vibrator made of material effecting the magnetic flux and disposed inside the casing, a vibration trigger disposed inside the casing to vibrate the vibrator, and circuitry to acquire frequency-related information related to the frequency of the oscillation signal output from the oscillator, detect the vibration of the vibrator based on a change of the frequency-related information, determine whether the vibration of the vibrator converges during a convergence-checking time period defined after the vibrator is vibrated by the vibration trigger, and detect the quantity of the fluid in the casing based on a convergence determination result of the vibration of the vibrator.

Abstract: A powder amount detector includes a vibration plate secured to a powder container to contain powder and positioned at a predetermined position in a stationary state, a shaft to rotate inside the powder container, a contact member attached to the shaft, a vibration detector to detect vibration of the vibration plate, and a detection result processor to determine an amount of the powder in the powder container according to a detection result generated by the vibration detector. The contact member is to flip the vibration plate to cause the vibration plate to repeat elastic deformation and reversion to vibrate. The contact member is to exit an area opposed to the vibration plate after the contact member flips the vibration plate by the time the vibration plate returns to the predetermined position.

Abstract: A sheet material thickness detection device includes a guide member, a non-rotating pressing member, a sensor, and a calculator. The guide member guides one side of a sheet material being conveyed. The pressing member presses the sheet material against the guide member in a manner displaceable in accordance with the thickness of the sheet material. The sensor is configured to magnetically or electrically detect a displaced amount of the pressing member that is displaced in accordance with the thickness of the sheet material. The calculator is configured to calculate the thickness of the sheet material based on an output signal of the sensor.

Abstract: A powder supply device that includes a powder reservoir including a rotator having a rotation shaft, to store powder supplied from a powder container; and a powder amount detector. The powder amount detector includes a detected member disposed in the powder reservoir, a contact member attached to the rotation shaft, to contact the detected member to vibrate or move the detected member, a detector to detect vibration or a displacement of the detected member, and a detection result processor to detect the amount of the powder in the powder reservoir based on detection by the detector. The powder supply device further includes a controller to supply the powder from the powder container to the powder reservoir based on detection by the powder amount detector. The controller rotates the rotator in discharging the powder from the powder reservoir and supplying the powder from the powder container to the powder reservoir.

Abstract: A developing device includes a developer bearer disposed opposite an image bearer and configured to rotate and carry developer to a latent image on the image bearer, a developer container to contain the developer, a detector including a detecting portion to detect a density of toner in the developer in the developer container, a wire connected to the detector, and a wire holder to hold the wire and determine a position of the wire relative to the detector.

Abstract: A powder amount detector includes a vibration plate secured to a powder container to contain powder and positioned at a predetermined position in a stationary state, a shaft to rotate inside the powder container, a contact member attached to the shaft, a vibration detector to detect vibration of the vibration plate, and a detection result processor to determine an amount of the powder in the powder container according to a detection result generated by the vibration detector. The contact member is to flip the vibration plate to cause the vibration plate to repeat elastic deformation and reversion to vibrate. The contact member is to exit an area opposed to the vibration plate after the contact member flips the vibration plate by the time the vibration plate returns to the predetermined position.

Abstract: A fluid detection apparatus to detect quantity of a fluid having flowability and stored in a casing includes an oscillator disposed outside the casing to output a frequency of an oscillation signal corresponding to a magnetic flux passing through a space near the oscillator, a vibrator made of material effecting the magnetic flux and disposed inside the casing, a vibration trigger disposed inside the casing to vibrate the vibrator, and circuitry to acquire frequency-related information related to the frequency of the oscillation signal output from the oscillator, detect the vibration of the vibrator based on a change of the frequency-related information, determine whether the vibration of the vibrator converges during a convergence-checking time period defined after the vibrator is vibrated by the vibration trigger, and detect the quantity of the fluid in the casing based on a convergence determination result of the vibration of the vibrator.

Abstract: A developing device includes a developer bearer disposed opposite an image bearer and configured to rotate and carry developer to a latent image on the image bearer, a developer container to contain the developer, a detector including a detecting portion to detect a density of toner in the developer in the developer container, a wire connected to the detector, and a wire holder to hold the wire and determine a position of the wire relative to the detector.

Abstract: A powder detector to detect an amount of powder in the powder container includes a vibration plate disposed in the powder container to vibrate, a contact member to vibrate the vibration plate; and a vibration detector to detect a vibration state of the vibration plate. The powder has flowability, and the vibration state of the vibration plate is affected by the powder in the powder container.

Abstract: A powder detector to detect an amount of powder in the powder container includes a wall without a through hole, a vibration plate attached to an inner face of the wall, a contact member to vibrate the vibration plate, and a vibration detector to detect a vibration state of the vibration plate. The vibration detector is attached to an outer face of the wall to face the vibration plate via the wall. The powder has flowability, and the vibration state of the vibration plate is affected by the powder in the powder container.

Abstract: A powder detection device includes a detection mechanism including an oscillation unit and a vibrated member, a vibrating member, and a detection unit. The oscillation unit outputs a signal having a frequency according to a state of a magnetic flux passing a space facing the oscillation unit. The vibrated member affecting the magnetic flux and disposed inside a container to face the oscillation unit via the container is vibrated by the vibrating member in a direction of facing the oscillation unit. The detection unit acquires frequency information of the signal at predetermined periods, determines presence/absence of an error of the detection mechanism based on error information associating a type of the error with a state of the signal, detects vibration of the vibrated member based on a change in the frequency information, and detects a remaining amount of powder in the container based on the detected vibration.

Abstract: A magnetic permeability detector includes an LC oscillator circuit including a coil and a capacitor; and a resistor connected in series with the coil.

Abstract: A magnetic permeability detector includes an LC oscillator circuit including a coil and a capacitor; and a resistor connected in series with the coil.

Abstract: A powder detector to detect an amount of powder in the powder container includes a wall without a through hole, a vibration plate attached to an inner face of the wall, a contact member to vibrate the vibration plate, and a vibration detector to detect a vibration state of the vibration plate. The vibration detector is attached to an outer face of the wall to face the vibration plate via the wall. The powder has flowability, and the vibration state of the vibration plate is affected by the powder in the powder container.

Abstract: A powder detector to detect an amount of powder in the powder container includes a vibration plate disposed in the powder container to vibrate, a contact member to vibrate the vibration plate; and a vibration detector to detect a vibration state of the vibration plate. The powder has flowability, and the vibration state of the vibration plate is affected by the powder in the powder container.

Abstract: A magnetic permeability detector includes an LC oscillator circuit including a coil and a capacitor; and a resistor connected in series with the coil.