A sheet supply apparatus detachably attached to an image forming apparatus is configured to receive a drive force from the image apparatus to supply sheet to the image forming apparatus. The sheet supply apparatus includes a sheet supply tray, a sheet supply roller, a first transmission mechanism configured to transmit a drive force from the image forming apparatus to the sheet supply roller, a second transmission mechanism including an output member and configured to transmit a drive force supplied from the image forming apparatus to the output member, a clutch mechanism configured to intermittently transmit a drive force from the image forming apparatus to the second transmission mechanism, a latch member pivotable between a restriction position and an allowance position, a change cam, a sector gear, a rotational force applying member, an engaging member, a first engagement portion, a second engagement portion, and an electromagnetic solenoid.

A medium feeding apparatus includes a feeding portion that performs a feeding operation, which feeds a medium to a downstream side, and a reverse feeding operation, which feeds the medium to an upstream side, and a wind-up portion that performs a wind-up operation, which winds up a medium fed to the downstream side by the feeding operation, and a unwinding operation that unwinds the wound up medium, in which the wind-up portion performs the unwinding operation prior to the reverse feeding operation.

The image forming apparatus includes a sheet storing unit insertably and pullably attached to the frame unit, an image forming unit, and a frame unit. The frame unit includes two frame members parallel to each other with a predetermined distance therebetween and are connected and fixed to each other. The two frame members respectively include engaged portions. The sheet storing unit includes engaging portions respectively engageable with the engaged portions in a state where the sheet storing unit is inserted in the frame unit. In a state where the engaging portions respectively engage with the engaged portions, the engaging portions that respectively engage with the engaged portions and a portion between the two engaging portions of the sheet storing unit serve as strengthening members to regulate deformation of the two frame members by at least a predetermined amount.

A medium feeding apparatus includes a feeding roller which feeds a medium unwound from a roll body around which the medium is wound, a roll motor which applies torque for rotating the roll body to the roll body, and a roll control portion which controls the roll motor at the time of a feeding operation based on effective tension calculated by acquiring a feeding amount of the medium fed at each of a plurality of acquiring timings included in a pre-feeding operation, which is a feeding operation performed in advance, acquiring tension applied to the medium between the roll body and the feeding roller between a plurality of the acquiring timings, and weighting a plurality of the acquired tensions with the corresponding feeding amount.

An image forming apparatus includes feeding, conveying, and separating members, and detecting, image forming, and control units. The feeding member feeds a recording material placed on a tray. The separating member and the conveying member separate recording materials at a nip. The detecting unit detects that the recording materials have been fed to the nip. The image forming unit forms an image on fed recording material. The control unit switches between a first and second control. Under the first control, the feeding member starts feeding a recording material placed on the tray, and ends feeding before a recording material trailing end passes through the feeding member. Under the second control, the feeding member starts feeding a recording material placed on the tray, and ends feeding after a recording material trailing end passes through the feeding member when the detection unit detects that the recording materials are fed to the nip.

In an inkjet printer, a controller is configured to calculate, during movement of a carriage in a scanning direction, a signal level difference between a first detection signal in a mountain peak zone including an assumed mountain peak position and the first detection signal in a valley bottom zone including an assumed valley bottom position identified, based on information stored in a storage, and alternately execute, during the movement of the carriage, an ejection process of ejecting ink drops, and a conveying process of conveying the sheet by a predetermined line feed width. In the printing process, the printing head and the conveyor are driven according to a first condition when the signal level difference is equal to or larger than a threshold value, while driven according to a second condition when the signal level difference is less than the threshold value.

A removable media tray with an adjustable rear tray extension operable by a rear media restraint. The tray extension is slidably attached to a front section of the tray via a cam having a locking arm engaged in a J-slot. When in the curved portion of the J-slot the front section and tray extension are locked together. A rear media restraint slidably latching to a track in the bottom of the tray has a locking lobe that engages with a locking notch on the cam. As the media restraint is slid toward the rear, the locking lobe initially rotates the cam moving the locking arm to the straight section of the J-slot, then the locking lobe engages with the locking notch, locking the media restraint to the tray extension. Thereafter, the media restraint and tray extension move together until the end of the J-slot is reached by the locking arm.

A printer includes a printer body and a lid. The printer body includes a recording paper holder configured to accommodate a roll of recording paper and a projection provided on a bottom surface of the recording paper holder that contacts the recording paper. The lid is attached to the printer body to be opened and closed relative to the printer body.

A roll-shaped medium transport device includes: a medium supply unit that keeps a roll body formed by winding a roll-shaped medium on a support shaft, and unwinds and supplies the roll-shaped medium; a transport unit that transports the roll-shaped medium unwound from the roll body; a rotation detecting unit that detects rotation of the support shaft; a rotation unit that rotates the support shaft; and a determination unit that determines abnormality of a transport state of the roll-shaped medium on the basis of the rotation detecting unit when the rotation unit rotates the support shaft, when the rotation detecting unit does not detect the rotation of the support shaft in a state where a transport operation of the roll-shaped medium is performed by the transport unit.

Meandering of a medium at a time of transporting is reduced. A recording apparatus which transports medium, and performs recording on the medium, the apparatus includes a recording unit; a medium clamping unit which is provided on a side further upstream than the recording unit in a transport direction, and clamps the medium therebetween; and a medium support unit which is provided on the side further upstream than the medium clamping unit in the transport direction, and supports the medium, in which the medium is slackened between the medium clamping unit and the medium support unit.