Abstract: A media tray including a first tray portion that has a base, an outer wall that is fixed to the base, and a locking mechanism is disclosed. The locking mechanism is substantially fixed in position relative to the outer wall. The locking mechanism is biased to a locked position and actuatable, along an axis that is at least substantially perpendicular to a longitudinal axis of the outer wall, for moving the locking mechanism to an unlocked position.

Abstract: A document feeder of an image forming apparatus includes a guide that arranges a width of a recording medium. A recording medium pickup module picks up the recording medium. A recording medium pickup module shifting unit shifts the recording medium pickup module in association with the movement of the guide. The recording medium pickup module includes a guide rack connected to the guide at one end. A pinion unit supports reciprocating motion of the guide rack. A pickup rack engaged with the pinion unit linearly reciprocates in parallel with the guide rack, and is connected to the recording medium pickup module.

Abstract: A method of measuring a paper size using a paper feeder having a fixedly mounted body part and a fastener apparatus movable depending on the paper size includes receiving light reflected from the body part with respect to an amount of a sent light, measuring the amount of the received light, and extracting information on a paper size corresponding to the measured amount of light from stored information. The extracted information of the paper size can be transmitted to a display unit, so that a user can recognize the information.

Abstract: A sheet cassette includes a tray main body part, and a tray expansion/contraction part supported by the tray main body part and configured to slide relative to the tray main body part to a cassette expanded position where the sheet cassette is in an expanded state and a cassette contracted position where the sheet cassette is in a contracted state. The tray expansion/contraction part includes a rear end regulation member configured to be moved in a direction in which recording media stacked in the sheet cassette are fed to regulate rear ends of the recording media and a sliding guide part configured to support the rear end regulation member to freely slide and forming a moving path of the rear end regulation member.

Abstract: A transmission mechanism of an image scanner with adjustable resolution is disclosed.

Abstract: A guiding and positioning apparatus for accurate guiding and input of a print media sheet to a business machine. The guiding and positioning apparatus includes a rotating shaft, a retaining member, a guiding member, a sliding member, a roller, a first spring, a second spring, a tray and a positioning element. The rotating shaft has a protrusion, a first end and a second end. The retaining member is fitted on the first end. The guiding member is fitted on the second end. The sliding member is fitted on the rotating shaft. The sliding member has a sliding groove and a guiding groove. The roller is fitted on the rotating shaft. The first spring is disposed between the retaining member and roller. The second spring is disposed between the roller and sliding member. The tray is disposed under the roller. The positioning element is formed on one side of the tray.

Abstract: A paper size recognizing device includes paper-aligning guides linear-reciprocally mounted to closely align the paper loaded in the cassette in one direction, a signal-generating unit interlocked with the paper-aligning guides, for generating plural signal codes selectively combined in predetermined patterns, switching unit mounted in the main body to be selectively operated in response to the signal codes generated by the signal-generated unit upon loading the cassette; and controller for outputting as an electrical signal paper size information on the paper loaded in a cassette through signal information inputted by operations of the switching unit, whereby the paper size information on the paper held in the container can be automatically recognized and provided in real-time upon loading the paper cassette.

Abstract: A sheet material guiding mechanism for guiding the edge portion of sheet material comprises a movable side guide capable of sliding corresponding to the sizes of sheet material, and being fixable in any position within the sliding area; a sheet guide section provided for the movable side guide in order to regulate the position of sheet material by butting against the edge of the sheet material; and an inner-side operating section provided for the movable side guide, being capable of releasing the fixed condition of the movable side guide by depression, hence making it possible to provide a sheet material guiding mechanism having a simple structure at lower costs, and producing the suppression effect against the skew of the sheet material with the easy operation that copes with disability.

Abstract: Systems and methods for adapting cassette guide movement for size detection includes, in exemplary embodiments, a one-piece member that transmits and rotates a movement of a guide member placed on a side of a sheet to a sheet size detector that detects a position of the guide member, wherein a first end of the connector is connected to the guide member and the second end of the connector is connector is connected to the sheet size detector.

Abstract: A paper feeding cassette includes a frame provided with a bottom plate to support paper and a plurality of walls to define a paper loading size. The paper feeding cassette also includes a loading size adjustment device to pivotally connect at least one of the walls to be hinged on the bottom plate, so that the at least one wall is movable between a vertical position to limit the paper loading size, and a horizontal position to not limit the paper loading size, enabling a variation of the paper loading size. Since the loading size of the paper feeding cassette is varied in accordance with a size of papers to be used, papers of various sizes may be used without having to increase a size of the cassette and an office machine which uses the cassette.

Abstract: A feeder for feeding products to be dispatched, such as, for instance, documents, periodicals, CDs, DVDs, and the like, to a conveyor of a packaging line, provided with transport pushers, the feeder being provided with a magazine for storing a stack of products, the dimensions of the magazine being settable through the setting of guides, wherein at least a number of the guides are in communication with a sensor, such that the position of the respective guide is known, while the control is arranged, on the basis of the signals coming from the sensors, to set at least one setting of a packaging line of which the feeder forms a part.

Abstract: A multi-part output paper tray 14 including a plurality of tray plates 21 to 24 slidably arranged together in a paper eject direction is attached to a printer assembly 1 so that it can be extended/collapsed, the printer assembly 1 including a print head attached thereto for forming an image on recording paper 50. The extended/collapsed state of the output paper tray 14 is detected by an angle sensor 313. A print operation is not performed when it is detected by the angle sensor 313 that the output paper tray 14 is in the housed state, and a print operation is performed when the output paper tray 14 is in the extended state.

Abstract: An image formation apparatus has a medium storage cartridge mounted in the image formation apparatus and a medium size detection device attached to the image formation apparatus. The medium storage cartridge has a medium back end stopper and a protrusion part. In a state in which the medium storage cartridge is mounted in the image formation apparatus, protruding protrusions of the protrusion part press a medium size detector and the medium size detector makes contact with through holes provided in a substrate and a medium size is detected by voltage states of the through holes.

Abstract: A sheet supply apparatus includes a sheet supply tray for stacking a sheet, and an auxiliary tray movable between a support position where the auxiliary tray supports a portion of the sheet stacked on the sheet supply tray and a storage position where the auxiliary tray overlaps the sheet supply tray. A sheet supply device supplies the sheet stacked on the sheet supply tray. A sheet detection device is mounted on the auxiliary tray for detecting the sheet stacked on the sheet supply tray, and a tray position detection device detects a position of the auxiliary tray between the support position and the storage position. An identifying device identifies a length of the sheet in a sheet supply direction based on detection results of the sheet detection device and the tray detection device.

Abstract: A sheet feeding device includes a cassette in which recording media are configured to be stacked. The cassette includes a rear end regulation member configured to be moved in a direction in which the recording media are fed to regulate rear ends of the recording media and a size detection device configured to swing with movement of the rear end regulation member. The sheet feeding device further includes a size determination device arranged within an area corresponding to a width of the cassette in the direction in which the recording media are fed. The size determination device is configured to determine a size of the recording media stacked in the cassette by detecting a position of the size detection device.

Abstract: The paper feeding cassette includes a push-up plate provided inside the cassette for receiving a stack of sheets entirely thereon regardless of the size of the sheets. On the push-up plate is mounted a trailing edge plate which is coupled to a fixing plate through a slide groove and which is configured to be capable of sliding in a sheet feeding direction in which the stacked sheets are to be fed to restrict the position of the stack of the sheets in the sheet feeding direction. The trailing edge plate is provided, at opposite sides thereof, with stoppers to be inserted into positioning holes of the push-up plate for fixing the trailing edge plate.

Abstract: A sheet feeder has a sheet tray 10 disposed in such a way as to be able to rotate around a shaft 12, which is provided in such a manner as to be nearly perpendicular to a sheet mounting surface 4b, and enabled to be accommodated in a sheet feeder body. The sheet feeder also has a step-like part 10a provided in the sheet tray 10 in such a fashion as to be placed in a connection portion, in which the sheet tray 10 and an upper edge part 4 of a sheet mounting portion 4 of the sheet feeder body are connected to each other, when the sheet tray 10 is used, and an abutting rib 13 for frontwardly pushing the sheet tray 10 when the sheet tray 10 is used.

Abstract: The present invention provides an automatic paper feed apparatus which can reliably prevent papers from being discharged in an overlapped state in spite of simple construction. The automatic paper feed apparatus comprises a paper feed roller for automatically feeding a plurality of papers in order from an uppermost one, with the plurality of papers being contained in a cassette in a stacked state. A holding member having flexibility is provided so that the holding member comes into contact with the uppermost paper to generate a friction force that is weaker than that between the paper feed roller and the uppermost paper.

Abstract: A rack-and-pinion print media guide system comprises two racks which are operatively coupled for reciprocal movement relative to each other by way of a central gear cluster instead of a single central gear (pinion) to expand the maximum media capture range. The gear cluster comprises first and second pinions and at least one center idler gear which is operatively coupled between the pinions with each rack skipping the center idler gear during operation.

Abstract: A printer including a main body and a sheet-supply cassette attachable to and detachable from the main body. The sheet-supply cassette includes a sheet guide movable to a position that depends on size of sheets in the cassette, cam abutment portion that moves integrally with the sheet guide, a cam that moves away from the cam abutment portion when the cassette is detached from the main body, and a detected portion that moves in a linked manner with the cam. The main body includes a cam mover that, when the sheet-supply cassette is attached to the main body, moves the cam until the cam surface of the cam abuts the cam abutment portion and a detection portion that detects the detected portion moved in a linked manner with the cam. The cam surface has a shape that varies movement amount of the cam into abutment with the abutment portion by the cam mover in accordance with the position of the sheet guide.

Abstract: When operating in a photocopier mode a first tray is first selected, and a second tray is then selected if there is no recording medium in the first tray. If recording medium is in the second tray but the size of the recording medium is not the same as the size of the recording medium loaded to the first tray, a notice indicating a size change is presented and recording is completed only if the user approves the size change using an operating panel.

Abstract: An image forming apparatus includes a media feed cassette 100 that is detachably attached to the image forming apparatus and contains medias used for printing therein. The media feed cassette 100 includes a chassis 100a; a cassette-side media stacking portion 101 which is mounted to said chassis 100a and contains medias therein, and is located within said image forming apparatus when it is attached to said image forming apparatus; a tray-side media stacking portion 102 being attached to said chassis 100a such that said tray-side media stacking portion is extendable to outside of said image forming apparatus, medias being put in said tray-side media stacking portion when it is extended outside; and a pickup unit 107 for picking up, sheet by sheet, medias put on said tray-side media stacking portion 102.

Abstract: A sheet member positioning device includes a plate on which a sheet member is loaded; a reference member provided at a side, in a first direction, of the plate, the sheet member being able to abut the reference member; a conveying member provided at a side, in a second direction, of the plate, and due to the conveying member being moved toward the side in the first direction and conveying the sheet member, the conveying member makes the sheet member abut the reference member so as to determine a position of the sheet member in the first direction; and a detecting mechanism which, at a time when the position of the sheet member in the first direction is determined, detects a distance between the reference member and the conveying member, and detects a size of the sheet member on the basis of the detected distance.

Abstract: A sheet feeding apparatus includes a sheet stacking unit, sheet feeding unit, and a sheet support member. Sheets are stacked on the sheet stacking unit. The sheet feeding unit is placed to be movable in the widthwise direction of the sheets stacked on the sheet stacking unit and feeds the sheets stacked on the sheet stacking unit. The sheet support member is placed at a position different from the position of the sheet feeding unit within an area where the sheet feeding unit can move, and supports the sheets stacked on the sheet stacking unit. The sheet support member can move in the widthwise direction of the sheet independently of the sheet feeding unit.

Abstract: A mobile, color printer capable of printing on letter-size plain paper and standard-size photo paper has a fold-up paper feeder that acts as a cover during travel. Such also serves as a storage tray for several sheets of paper to allow automatic feeding from a vertical stack. A slotted door hinged to the back of the printer, and under the hinges for the fold-up paper feeder/cover, can be flipped up or down. In the down position, a slot on the right side guides the user to feed in photo paper in the correct location. In the up position, letter-size plain paper has full-width access to the printing mechanism, and a sliding adjustable guide on the left allows letter, A4, and other size papers to be lightly corralled on both sides.

Abstract: A paper cassette for an image forming apparatus includes a cassette body, a pair of aligning plates, paper separating fingers, and a biasing member. The cassette body has a knock-up plate on which paper is stackable. The pair of aligning plates are disposed on the paper cassette body and moving in a widthwise direction for aligning paper stacked on the knock-up plate in the widthwise direction. The paper separating fingers are disposed on the aligning plates and are vertically movable to a predetermined distance above the aligning plates, for pressing against two corners of a leading edge of an uppermost sheet of paper stacked on the knock-up plate. The biasing member is connected to at least a side of one of the paper separating fingers, for increasing a relative downward pressure exerted by the paper separating finger on the uppermost sheet of paper stacked on the knock up plate.

Abstract: A sheet guiding system guides different sized sheets so as to be fed in a first direction. Sheets stacked on a sheet tray are guided by selectively using a fixed guide, a first movable guide, and a second movable guide. The fixed guide is provided on the sheet tray immovably in a second direction perpendicular to the first direction. The first and second movable guides are provided on the sheet tray and are movable in the second direction. The fixed guide and the first movable guide are used to sandwich and guide the sheets that have a first dimension in the second direction equal to or larger than a predetermined dimension, which is, for example, a width of an A4 size sheet. The first and second movable guides are used to sandwich and guide the sheets that have a second dimension in the second direction smaller than the predetermined dimension.

Abstract: A sheet transport apparatus includes a paper feed stacker for stacking a sheet; a first sheet control device for abutting against an edge of the sheet to control a width direction of the sheet and being movable in the width direction; a discharge device for discharging the sheet transported from the paper feed stacker and processed at a predetermined processing unit; a discharge stacker arranged to overlap the paper feed stacker for stacking the sheet; and a second sheet control device for controlling the width direction of the sheet by abutting against the side edge of the sheet discharged to the discharge stacker and being synchronized to a movement of the first sheet control devices. The second sheet control device has a contact member rotatable between a position for controlling the sheet and a position where the sheet can be removed.

Abstract: A paper cassette holds a stack of print medium therein. A guide member includes first and second members. A medium-supporting plate supports the stack of the paper placed thereon. When the guide member is moved to a predetermined position, the first member abuts the end of the stack of print medium and the second member slides under the edges of the paper placed on the medium-supporting plate. The second member has a tapered forward end portion that allows the second member to smoothly slide under the bottom of the stack of print medium. The guide member is guided in a groove to move to and from the stack of print medium. The second member has a flat portion and the tapered forward end portion extends further away from the flat portion than the bottom of the stack of print medium.

Abstract: An end fence for use in a sheet feeding cassette includes an end fence main body attached to the sheet feeding cassette and movable along a sheet feeding direction, a device that fixes the end fence main body at any desired position in the sheet feeding cassette, and a sheet pressing element that presses against trailing edges of the sheets loaded on a bottom plate of the sheet feeding cassette. The sheet pressing element is provided to the end fence main body and movable in the sheet feeding direction and protrudes from the end fence main body forward in the sheet feeding direction when the sheet pressing element moves in the sheet feeding direction. The end fence further includes a biasing device that biases the sheet pressing element forward in the sheet feeding direction, and a bias force switching device that switches between a biasing condition and a non-biasing condition.

Abstract: A sheet supply apparatus for supplying stacked sheets includes a standard sheet tray provided with a standard side guide that regulates a position in the width direction of the stacked sheet, and an extension sheet tray extendably disposed upstream of the standard sheet tray in a sheet feeding direction, wherein the extension sheet tray has an auxiliary side guide that regulates a position in the width direction of a sheet feeding direction upstream portion of a long sheet. A sheet handling apparatus using the sheet supply apparatus.

Abstract: A printer paper support system includes a housing, a first paper support pivotally attached to the housing and a second paper support pivotally attached to the housing, the second paper support extending the first paper support.

Abstract: A recording plate or film loading device for use with an image recording scanner. The device comprises a platen (6) arranged at an angle to the horizontal and onto which a plate or film is manually placed. A loading mechanism includes one or more first pusher members (12) cooperating with the platen to push a plate or film to an output position. A centering mechanism includes a pair of second pusher members (13) movable laterally with respect to the platen (6) to centre a plate or film on the platen.

Abstract: A tray for holding a stack of media sheets for feeding into a printing mechanism is provided. The tray has a first media guide movable relative to a first wall of the tray in a first direction to vary a first spacing there between for accommodating different media sizes in the first direction. The tray also has a second media guide manually adjustable relative to a second wall of the tray in a second direction to vary a second spacing there between for accommodating different media sizes in the second direction. The second direction is substantially perpendicular to the first direction. Furthermore, the movements of the first guide are synchronized with movements of the second guide so that adjustment of the first guide is automatically achieved through the manual adjustment of the second guide.

Abstract: A sheet feeding apparatus includes a sheet storage portion that can store sheets with various sizes and accurately detect a size of the sheets. The sheet feeding apparatus has a sheet storage device, a supporting device for supporting the sheet storage device in a moving path between a sheet replenishing position and a sheet feeding position, a frame for fastening the supporting device, a sheet feeding device for separating the sheets into a single sheet and feeding the single sheet, and a sheet size detecting device established in the moving path for detecting the size of the sheets stored in the sheet storage device. The sheet size detecting device overlaps the sheet storage device in a sheet stacking direction when the sheet storage device is positioned at the sheet feeding position.

Abstract: A sheet containing apparatus including: a sheet stacking portion which is provided in an apparatus main body and on which sheets are stacked; and a regulating member provided on the sheet stacking portion so as to be movable according to the size of the sheets stacked on the sheet stacking portion and adapted to abut against edges of the stacked sheets to regulate the position of the sheets, in which there is provided a positioning member for effecting positioning on the regulating member on upper and lower sides with respect to the apparatus main body.

Abstract: A sheet supply cassette includes a main frame body and an auxiliary frame body slidable with respect to the main frame body. In the main frame body, there is disposed a sheet placement plate which moves up and down according to the residual quantity of sheets placed, and there is disposed a sheet residual quantity display mechanism which displays the sheet residual quantity according to the upward and downward movements of the sheet placement plate. The display mechanism includes a sheet residual quantity detect portion for detecting the residual quantity of sheets, a sheet residual quantity display portion disposed on the front surface cover portion of the auxiliary frame body, and a connecting portion for connecting together the sheet residual quantity detect portion and sheet residual quantity display portion, while the connecting portion can be expanded and contracted according to the expansion and contraction of the sheet supply cassette.

Abstract: A paper tray assembly for providing imaging media to an imaging apparatus, includes a base cassette and an insert cassette. The base cassette defines a first receptacle to receive at least a portion of the insert cassette, and the insert cassette defines a second receptacle to receive the imaging media.

Abstract: A printer paper tray improper loading protection system which is automatically moved by the repositioning of a conventional repositionable stack edge guide to restrict improper loading of sheets into the area of the tray which is outside of the proper sheet stacking area for sheet feeding, even though that restricted area varies depending on the selected size of the sheets being properly loaded within the proper sheet stacking area. A customer warning and partial obstruction of the non-feeding restricted area of the tray eliminates confusion as to where the operator should load paper into the tray whenever the tray is accessed, no matter where the tray stack edge guides are positioned for different paper sizes. An accordion-folded, reeled, or other expandable and contractible member operatively connects between the repositionable stack edge guide and the opposite end of the tray, extending above the tray stacking surface therebetween.

Abstract: A sheet containing device including a device frame, a sheet stacking portion that is provided in the device frame and supports sheets, an end regulating portion that abuts against an end of sheets stacked on the sheet stacking portion to perform positional regulation of the sheets, a hitting member that is arranged between the device frame and the end regulating member and moves in accordance with the movement of the end regulating member, and an abutting member for abutting the hitting member in a position to which the hitting member moves, in which deflection of the end regulating member is restricted by the device frame through the hitting member and the abutting member.

Abstract: A recording apparatus has a feed mechanism for feeding a recording medium loaded on a recording-medium loading section; a recording unit for recording on the recording medium fed by the feed mechanism; and a recording-medium discriminating device for discriminating the type of recording medium loaded on the recording-medium loading section. The type of recording medium is discriminated by the recording-medium discriminating device before the feeding operation by the feed mechanism, and the operation of the recording unit is controlled according to the type of recording medium stored in a memory.

Abstract: A sheet size detection apparatus including, a sheet stacking device on which sheets are stacked and which can be loaded into and unloaded from a loading portion, a sheet size selection member provided on the sheet stacking device, a position of the sheet size selection member being changeable in accordance with a size of stacked sheets, a sheet size detection device provided on the loading portion for detecting the sheet size based on a relative positional relationship with the sheet size selection member, a locking member that can lock the sheet size selection member, and an unlock member for releasing a locking operation of the locking member.

Abstract: An automatic adjusting device for a bank note holding member is provided. The bank note holding member can be inserted into a safe for the dispensing of bank notes. The holding member can have relatively movable side and end walls which can automatically and mechanically adjust to the particular size of the stack of bank notes that are inserted therein. When the bank note holding member is removed, the walls can be automatically extended to open the space to receive bank notes. When the bank note holding member is inserted into a safe, the respective walls can close on the stack of bank notes and assert a predetermined force to align the bank notes stored therein.

Abstract: A sheet size detecting device is provided with the following a tray in which sheets are stored, guides that can be adjusted in position in accordance with the size of sheets stored in the tray, and bit generation sections that are moved in synchronism with movement of the guides. The device detects bits based on the movement of the bit generation sections, and the number of bits detectable is larger than the number of bit generation sections by at least one. The device detects the size of sheets stored in the tray on the basis of the correspondence between the combination of detected bits and the sizes of sheets which can be stored in the tray.

Abstract: A sheet guiding system guides different sized sheets so as to be fed in a first direction. Sheets stacked on a sheet tray are guided by selectively using a fixed guide, a first movable guide, and a second movable guide. The fixed guide is provided on the sheet tray immovably in a second direction perpendicular to the first direction. The first and second movable guides are provided on the sheet tray and are movable in the second direction. The fixed guide and the first movable guide are used to sandwich and guide the sheets that have a first dimension in the second direction equal to or larger than a predetermined dimension, which is, for example, a width of an A4 size sheet. The first and second movable guides are used to sandwich and guide the sheets that have a second dimension in the second direction smaller than the predetermined dimension.

Abstract: A sheet feed cassette includes a case, and right and left guide members that are disposed in the case and guide edges of a sheet parallel with a sheet feeding direction. The guide members are movable in a sheet width direction in synchronization with each other. The guide members are adjusted in association with a size of the sheet to be accommodated in a sheet accommodation area. The right guide member includes a slide member and a leaf spring attached to the slide member. As the right guide member is moved toward a side wall of the case, a protrusion extending from the side wall contacts the leaf spring, through a slit formed on the slide member. The leaf spring is deformed and the sheet accommodation area in the case gradually becomes larger toward a sheet stacking direction from a bottom of the case.

Abstract: A self-adjusting side guide for a document-handling machine having a feed deck along which documents are transported is provided. The self-adjusting side guide includes a first member mounted for movement along the feed deck toward and away from the documents; a guide wall mechanism operatively connected to the first member for movement relative to the first member; and a biasing device that applies a biasing force that biases the guide wall into a first position relative to the first member. The side guide operates such that at times when an external force sufficient to move the first member along the feed deck in the direction of the documents is applied to the guide wall mechanism, the guide wall mechanism moves toward the documents against the biasing force from the first position to a second position relative to the first member without any movement of the first member toward the documents.

Abstract: A paper cassette for an image forming apparatus includes a cassette body, a pair of aligning plates, paper separating fingers, and a biasing member. The cassette body has a knock-up plate on which paper is stackable. The pair of aligning plates are disposed on the paper cassette body and moving in a widthwise direction for aligning paper stacked on the knock-up plate in the widthwise direction. The paper separating fingers are disposed on the aligning plates and are vertically movable to a predetermined distance above the aligning plates, for pressing against two corners of a leading edge of an uppermost sheet of paper stacked on the knock-up plate. The biasing member is connected to at least a side of one of the paper separating fingers, for increasing a relative downward pressure exerted by the paper separating finger on the uppermost sheet of paper stacked on the knock up plate.

Abstract: A system to detect if the positions of a tray's sheet guides have been changed while the tray has been open includes a spring loaded stud in the tray that is pushed and locked into an ‘in’ position every time the tray is pushed in. When the tray is pulled out, if the size guides are moved, the spring-loaded stud is released by a linkage mechanism from the guides to the stud. The stud actuates a sensor flag, and as the tray is pushed home, a sensor checks the flag and a control system subsequently deduces whether the guides have been moved.

Abstract: A paper feed cassette having a size detection function has a paper stage formed integrally with a rear end restricting plate for restricting the rear end of paper sheets. On the bottom of the paper stage, a plurality of rib-like detection targets are arranged in the paper feed direction. The detection targets are detected by a plurality of detection switches arranged in the paper feed direction in a paper feed portion inside the main body of an image forming apparatus. A discriminator receives the detection signals from the detection switches and thereby recognizes the paper size and the presence/absence of the paper feed cassette.