A sheet feeding device includes: a sheet stacking unit that stacks a bundle of sheets; a pick-up roller that is enabled to move up and down and sends a sheet of the bundle of sheets toward downstream side in a carrying direction; a pair of rollers that is arranged at downstream side in the carrying direction, and when multiple sheets are sent out by the pick-up roller, that separates the first sheet from the second sheet or later; a separation member that is arranged between the pick-up roller and the pair of rollers and that is in contact with a leading end of the sheet and limits the number of the sheet carried to the pair of rollers; and a hardware processor that determines a height position of the pick-up roller corresponding to a type of the sheet and sets the pick-up roller to be at the determined height position.

A medium conveying apparatus includes a conveyance roller to convey a medium, a motor to drive the conveyance roller, a signal generator to output a pulse signal, a pulse width of which changes according to a rotation speed of the motor, and a processor to rotate the conveyance roller by controlling the motor, and detect a fluctuation of the pulse width caused by a load fluctuation when the conveyance roller conveys a medium to determine a thickness of the medium according to the pulse width.

A medium conveying apparatus includes a conveyance roller to convey a medium, a motor to drive the conveyance roller, a signal generator to output a pulse signal, a pulse width of which changes according to a rotation speed of the motor, and a processor to rotate the conveyance roller by controlling the motor, and detect a fluctuation of the pulse width caused by a load fluctuation when the conveyance roller conveys a medium to determine a thickness of the medium according to the pulse width.

To reduce, at the time of sheet replenishment, breakage of a floating regulation member that regulates floating of a sheet floated by air blowing in a sheet storage apparatus that loosen stored sheets by means of air blowing. Air is blown to sheets stored in a storage part to loosen the sheets. One of a pair of side regulation members for regulating both ends of the sheets stored in the storage part has a floating regulation member for regulating floating of a sheet floated by means of air blowing. The floating regulation member is configured to be turnable in a sheet stacking direction about a rotation axis provided to one of the side regulation members on the side at which the floating regulation member is provided. A load applied to the floating regulation member differs between when the floating regulation member is turned upward and when it is turned downward.

A method for detecting irregularities on a material strand made of an elastomeric material comprises the steps of: (a) providing a material strand which defines a longitudinal axis along which the material strand is to be conveyed; (b) bringing a detection element in contact with the material strand, wherein at least one of the detection element being movably mounted in a direction of deflection transverse to the longitudinal axis and a force can act on the detection element in a force direction, (c) setting up a relative movement between the detection element and the material strand along the longitudinal axis; and (d) detecting at least one of a deflection of the detection element in the deflection direction and a force acting on the detection element in the force direction, so as to detect irregularities in the material strand.

To reduce, at the time of sheet replenishment, breakage of a floating regulation member that regulates floating of a sheet floated by air blowing in a sheet storage apparatus that loosen stored sheets by means of air blowing. Air is blown to sheets stored in a storage part to loosen the sheets. One of a pair of side regulation members for regulating both ends of the sheets stored in the storage part has a floating regulation member for regulating floating of a sheet floated by means of air blowing. The floating regulation member is configured to be turnable in a sheet stacking direction about a rotation axis provided to one of the side regulation members on the side at which the floating regulation member is provided. A load applied to the floating regulation member differs between when the floating regulation member is turned upward and when it is turned downward.

A transport unit includes a glue belt, a pressurizing roller, a roller driving unit, and a control unit. The glue belt includes an adhesive layer. The pressurizing roller presses a medium against the adhesive layer while reciprocating in a Y direction. The roller driving unit generates a driving force for the pressurizing roller to reciprocate. The control unit controls the roller driving unit. The pressurizing roller is separated from the adhesive layer along with reciprocation. The control unit is capable of detecting a load of the roller driving unit, and determines whether the magnitude of the adhesive force of the adhesive layer is less than a target value, based on the load.

Included are a feeding shaft configured to hold a printing medium, a first transporting belt, a second transporting belt, a first driving roller on which the first transporting belt is wound, a second driving roller on which the second transporting belt is wound, a first driving unit configured to drive the first driving roller, a second driving unit configured to drive the second driving roller, a winding roller on which the printing medium is wound, a first winding roller bearing, a second winding roller bearing, a first load cell configured to detect a load exerted by the printing medium on the first winding roller bearing, a second load cell configured to detect a load exerted by the printing medium on the second winding roller bearing, and a control unit configured to control the first driving unit and the second driving unit based on detection results of the load cells.

A sheet stacking part stacks sheets. A first roller applies a force in a conveyance direction to an uppermost sheet among sheets stacked on the sheet stacking part by rotating in a forward direction. A second roller is separated from the first roller on the downstream side in the conveyance direction. The second roller applies the force in the conveyance direction to the uppermost sheet by rotating in the forward direction. A controller controls rotation of the first roller and the second roller so that a second main operation is performed after a first main operation. The first main operation is an operation of rotating only the first roller of the first roller and the second roller in the forward direction. The second main operation is an operation of rotating both the first roller and the second roller in the forward direction.

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.