A medium accommodation cassette includes a first medium accommodation portion that forms a portion of a medium accommodation region and a second medium accommodation portion that forms a portion of the medium accommodation region and is configured to be switchable between a first state and a second state in which the second medium accommodation portion is displaced from a position thereof in the first state in a cassette removing direction so as to stretch the medium accommodation region. A step portion on a side surface, which is formed between the first medium accommodation portion and the second medium accommodation portion, is positioned inside an insertion/removal mouth when the second medium accommodation portion assumes the second state in the state in which the medium accommodation cassette is installed in the insertion/removal mouth.

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 paper sheet feeding apparatus includes an inserting unit in which a paper sheet is inserted, a pick-up roller for picking up a paper sheet inserted in the inserting unit, a rotating shaft for rotating the pick-up roller, a detecting member that is supported by the rotating shaft so as to be able to rotate around the rotating shaft and is rotated by a bundling member that bundles paper sheets together, and a first detecting unit that detects rotation of the detecting member.

An image forming apparatus includes a paper discharging tray and a paper detection part disposed at an upstream end of the paper discharging tray in a paper discharge direction. The paper detection part includes a base end member provided rotatably around a first axis extending in a direction perpendicular to a paper discharge direction and a tip member pivoted to the base end member to rotate around a second axis parallel to the first axis, and extending downwardly to incline toward an upstream side of the paper discharge direction in a state where the base end member is not subjected to pressure from the paper being discharged. The base end member is disposed to face a discharge opening when being at the reference position, and the image forming apparatus stops discharging paper from the discharge opening when the base end member rotates by a predetermined threshold or more with respect to the reference position.

A sheet stacking device includes a stacker, a detector, a blower, and a moving device. A sheet is stacked on the stacker. The detector detects a stacking amount of the sheet on the stacker. The blower blows air to the sheet stacked on the stacker. The moving device moves the blower with respect to the stacker based on the stacking amount of the sheet detected by the detector.

A sheet feeding apparatus includes a sheet stacking portion, a lift plate, an actuating segment, driving unit, a sheet feeding portion, a first detecting portion, a remaining amount detection portion. The remaining amount detection portion includes a detection piece, a link mechanism, a second detecting portion, a controller. The link mechanism couples together the driving shaft and the detection piece at a coupling position attained by pivoting the lift plate through a predetermined angle from a lower limit position in rotation direction, so as to let the driving shaft and the detection piece rotate together. The second detecting portion senses whether or not the detection piece is present. The controller determines the remaining quantity level of the stacked sheets according to whether or not the second detecting portion is detecting the detection piece being present.

An image forming system includes an image forming apparatus, a first conveyance path, a sheet feeding unit, a sheet post-processing unit, and a controller. The image forming apparatus has a first feed portion, and an image forming portion. The sheet feeding apparatus has a sheet stacking portion, a second feed portion, a relay conveyance portion, and a remaining amount detecting portion. When, during continuous printing, the existing number of recording sheets present in a conveyance passage from a confluence portion to the first feed portion is more than the constituting number of recording sheets contained in one bundle of sheets and in addition the sensing result of the remaining amount sensor is equal to or less than a predetermined amount, the controller controls first feed portion such that the existing number of the recording sheets is less than the constituting number of recording sheets.

An image forming apparatus includes a paper discharging tray and a paper detection part disposed at an upstream end of the paper discharging tray in a paper discharge direction. The paper detection part includes a base end member provided rotatably around a first axis extending in a direction perpendicular to a paper discharge direction and a tip member pivoted to the base end member to rotate around a second axis parallel to the first axis, and extending downwardly to incline toward an upstream side of the paper discharge direction in a state where the base end member is not subjected to pressure from the paper being discharged. The base end member is disposed to face a discharge opening when being at the reference position, and the image forming apparatus stops discharging paper from the discharge opening when the base end member rotates by a predetermined threshold or more with respect to the reference position.

An automatic lifting and feeding device includes a main controller, a material thickness detecting device, a material loading mechanism for placing materials and driving the materials to rise and fall, a material taking mechanism for transferring materials and a height detecting mechanism for detecting the height of the materials, wherein, the material thickness detecting device, the material loading mechanism, the material taking mechanism and the height detecting mechanism are respectively connected to the main controller. The height detecting mechanism includes a bracket and the height testing part connected to the bracket, and the detector for detecting the material distance is arranged on the height testing part. The invention also provides an automatic lifting feeding method. The advantage of the invention is that the height does not need to be adjusted manually. The device can automatically detect the height of the material, and achieves high efficiency.

In some examples, a non-transitory machine readable medium can include instructions executable by a processing resource to assert a low print media level notification responsive to determination that a first amount of print media in a media receptacle of an imaging device is less than a set value, detect a second amount of print media in the media receptacle of the imaging device, compare the detected second amount of print media to a print media threshold that is based on the set value and a selectable print media value, and maintain the low print media level notification responsive to a determination that the detected second amount of print media is less than the print media threshold.