A sheet feeding apparatus includes a supporting portion, a regulating unit supported to be movable in a first direction, a feed unit, a variable resistor including a rotary member configured to be rotated by a movement of the regulating unit in the first direction, and having a resistance value changing according to a rotational phase of the rotary member, an interlocking portion configured to rotate the rotary member in conjunction with the regulating unit, and a substrate including a pattern surface to which the variable resistor is connected. An axial center line of the rotary member extends in a second direction orthogonal to the first direction and a direction of gravitational force. The substrate is disposed such that the pattern surface extends in parallel with the first direction and the direction of gravitational force.

A sheet feeding device includes a tray to store a stack of sheets, and a sheet elevation mechanism provided at the bottom of the tray to lift the stack of sheets until a top sheet of the stack of sheets reaches a predetermined height position. A paper feed roller is disposed above the tray to come in contact with the top sheet having reached the predetermined height position and rotated by a motor to deliver the top sheet from the tray. Additionally, the sheet feed device includes a controller to control the sheet elevation mechanism based on a drive torque of the motor to adjust the height position of the stack of sheets, after delivery of the first sheet from the tray by the paper feed roller and upon delivery of a second sheet by the paper feed roller. The frictional force to be produced between the second sheet and the paper feed roller is substantially equal to the frictional force produced between the first sheet and the paper feed roller during delivery of the first sheet.

A sheet feeding device includes a tray to store a stack of sheets, and a sheet elevation mechanism provided at the bottom of the tray to lift the stack of sheets until a top sheet of the stack of sheets reaches a predetermined height position. A paper feed roller is disposed above the tray to come in contact with the top sheet having reached the predetermined height position and rotated by a motor to deliver the top sheet from the tray. Additionally, the sheet feed device includes a controller to control the sheet elevation mechanism based on a drive torque of the motor to adjust the height position of the stack of sheets, after delivery of the first sheet from the tray by the paper feed roller and upon delivery of a second sheet by the paper feed roller. The frictional force to be produced between the second sheet and the paper feed roller is substantially equal to the frictional force produced between the first sheet and the paper feed roller during delivery of the first sheet.

An image forming apparatus is provided. The image forming apparatus includes an engine unit to be used for performing an image forming job, a motor to start the engine unit, a driver circuit to sense a current flowing in the motor and supply the motor with a power source, and a processor to determine a load size of the motor based on the sensed current and control a driving speed of the motor based on the determined load size.

An image forming apparatus is provided. The image forming apparatus includes an engine unit to be used for performing an image forming job, a motor to start the engine unit, a driver circuit to sense a current flowing in the motor and supply the motor with a power source, and a processor to determine a load size of the motor based on the sensed current and control a driving speed of the motor based on the determined load size.

Embodiments disclosed herein include a sensor wafer. In an embodiment, the sensor wafer comprises a substrate, wherein the substrate comprises a first surface, a second surface opposite the first surface, and an edge surface between the first surface and the second surface. In an embodiment, the sensor wafer further comprises a plurality of sensor regions formed along the edge surface, wherein each sensor region comprises a self-referencing capacitive sensor.

A recording system includes a recording device including a recording unit that performs recording onto a medium, a transporting belt that includes an adhesive layer and transports the medium stuck on the adhesive layer, a drive unit that drives the transporting belt, a control unit that includes a detection unit for detecting a load current flowing in the drive unit and that controls the drive unit. The recording system further includes a peeling device that peels the medium from the transporting belt, and a notification device that provides a notification. The control unit causes the notification device to provide a notification on a time to replace the adhesive layer, based on a detection result of the detection unit.

An image forming apparatus includes a stacking portion, a pickup roller, a motor, an image forming unit, and a controller. Upon receiving an instruction for starting a first image forming job, the controller performs an initial operation of supplying current to a motor winding of the motor in a stop state and determining a phase of the rotor based on the flowing current. Based on the determined phase, the controller supplies current to rotate the rotor from its stop state and holds the rotor at a first phase when the first job ends. Upon receiving start instructions for a second image forming job within a period until a predetermined time elapses from when the rotor is held at the first phase, the controller rotates the rotor without performing the initial operation. The controller stops supplying current to the winding if no instructions are not received for starting the second job.

A medium processing device includes: a drum that is rotatably supported, that rotates around a rotation axis, and that winds a medium around a peripheral side surface thereof; a first tape that winds the medium sandwiched between the peripheral side surface and the first tape, accompanying rotation of the drum; a movable guide that is movable following a drum diameter of the drum, which changes depending on a winding amount of the medium, and that guides the medium; and a first static electricity elimination section that is provided at the movable guide, that abuts the first tape, and that performs static electricity elimination of an electric charge of the charged first tape.

An image forming apparatus is provided. The image forming apparatus includes a print engine to be used to perform an image forming job, a motor to start the print engine, a driving circuit to supply a power to the motor and to include a sensor to sense a size of current of the power supplied to the motor during an operation to perform the image forming job, and a processor to detect an occurrence of jam based on a size of current sensed by the sensor in a first time interval while the motor is driven and a size of current sensed by the sensor after a determined time from the first time interval.