Patent Application
20060227387
All references cited in this specification, and their references, are incorporated by reference herein where appropriate for teachings of additional or alternative details, features and/or technical background.
Disclosed is a document drive or media drive system for an image reading apparatus such as a document scanning apparatus comprising an integrated imaging system such as an image sensor device, fixed inside the lumen (that is the cavity) of a rotatable platen, and a pinch or backer roller configured to operatively engage the platen to cause a document to be pulled through the image reading apparatus. In particular, the rotatable platen comprises a cylindrical or tubular structure which serves as part of the document drive mechanism of the apparatus and rotates independently of the imaging system. More particularly, the cylindrical or tubular platen comprises a near light-transmissive quality clear plastic such as polycarbonates including cast Lexan®, which also protects the imaging mechanism from deterioration from dirt and debris.
Document scanners or image reading apparatuses, such as that described in U.S. Pat. No. 4,536,077, generally consist of a document supply tray, one or more scanning stations; a mechanism for forming a path for conveying a document removed from the tray past the scanning stations; a document transport mechanism for transporting the document from the supply tray through the scanning stations and back to the tray; an illuminating mechanism, at least one scanning array and an optical system for selectively transmitting images of the document portion viewed through the scanning arrays.
U.S. Pat. No. 5,526,141, for example, describes an original image reading device which includes a first supporting device having a platen roller provided on a side of an original opposed to an image reading device, for conveying the original at a position deviated from an original reading position, and a non-cylindrical original contact device for urging the original toward the image reading device. U.S. Pat. No. 5,526,141 also discloses that the image reading device also has a second supporting device which has a contact-type reading sensor and it is combined with the first supporting device at a fulcrum at an original exit side so as to relatively rotate. The patent also discloses that the original platen roller is separated from the second supporting device upon relative rotation of the first and second supporting devices.
U.S. Pat. No. 5,676,368 discloses a document drive apparatus for directing a document around a corner. The document drive has a drivable drum with a central axis and is rotatably mounted on a mounting surface of a base member in the form of a base plate.
U.S. Pat. No. 5,982,512 discloses a document feeder for a facsimile machine which includes a reading roller for a document reading unit, a shaft about which the roller rotates, a hollow rubber roller through which the shaft is located, an elastic rubber cylinder of a predetermined length mounted inside the rubber tube at the center, and a pair of levers each having a bushing to support the shaft an eccentric cam inserted into each hole of the frames to separate the reading roller from the document reading section thereby connecting the reading rollers to the frames. The document feeder also has brackets attached to both ends of the document reading section to connect the document reading section to the frames.
U.S. Pat. No. 6,771,917 discloses an image forming apparatus consisting of a body having a document table portion on which a document is placed, a scanning unit inside the apparatus body to optically scan an image of the document place on the document table portion, an image forming unit for forming a developer image on a photosensitive drum in accordance with the image information scanned by the scanning unit, a transfer charger for transferring the developer image formed by the developer image unit on a sheet, a fixing unit for fixing the developer image transferred by the transfer charger on the sheet, an ejecting roller for ejecting the sheet on which the developer image is fixed, a sheet receiving unit and a blowing unit for blowing cool air to the sheet receiving unit.
Driving circuits and functional representation of the image bars, for example, are described in U.S. Pat. No. 5,260,718.
Conventional media drive systems are complicated to operate and have limited motion quality performance and reliability. They are also expensive to manufacture. Accordingly, there is a need to produce media drive systems and scanning devices for copiers and printers and scanners which are more compact and with cheaper, smaller and reliable equipment for high quality copying, scanning and printing apparatuses.
Aspects disclosed herein include
a document scanning apparatus comprising a cylindrical, movable or rotatable platen having a lumen, and optionally one or more sensors; the platen housing one or more light exposure sources, a lens, and an integrated imaging bar assembly in the lumen, and being operatively coupled to a motor and independently rotatable; and
a media drive and imaging apparatus comprising a pinch or backer roller configured to operatively engage a tubular, rotatable platen to cause a document to be pulled through an image reading device; wherein the tubular, rotatable platen comprises an light-transmissive quality or near light-transmissive quality, durable plastic tube with an illumination system and an imaging system located inside said tube and mounted on support structures.
In embodiments there is illustrated:
A document scanner or image reading apparatus is provided with a document drive and imaging assembly integrated within a simple and compact structure. In one embodiment, the document scanner comprises illuminators and scanning equipment such as video boards and the like which are stored or protected within a tube which is used as the platen for moving a document.
As illustrated in
The document scanner apparatus further comprises one or more light exposure or illumination sources such as mercury lamps, fluorescent lamps, light emitting diode (LED) arrays or a reflector, which are housed in the lumen (that is, the cavity) of the platen tube 30. The image reading apparatus can optionally comprise one or more sensors, such as encoders, which can be attached to the tube and can provide auto-timing. In this embodiment, light exposure sources, lens, and an integrated scanning raster input bar assembly, comprising, for example, a light emitting diode, are in a fixed position inside the movable platen and are structurally configured at its end to operatively engaged with the support structure 10 and be structurally adapted to be shielded from dirt. The raster image assembly 40 remains fixed in its support during operation or rotation of the platen 30.
In certain embodiments, the lens system of the imaging bar can comprise, for example, mirrors, imaging sensors, and full width array lenses such as a lens with, for example, from about 3 to about 5 arrays, which may be combined with a raster input bar or a raster output bar. A heat sink or heat absorbable structure 50 is provided, which is made of a material capable of absorbing or dissipating heat generated from the raster input bar or raster output bar electronic circuitry which drive photosensors and light emitting devices, such as materials comprising high thermal conductivity including, aluminum, and ceramic material. Heat sinks 50 can be structurally configured in any shape that will accommodate efficient heat removal from the imaging bars. In one embodiment, the media drive and scanning apparatus may comprise a heat shield operatively configured to minimize heat transfer from the imaging system components, for example, a heat shield may comprise structures made of, for example, stainless steel, which can be integrated in close relationship with a heat sink 50 in an imaging bar assembly to control heat in the apparatus.
In one embodiment, addressable image bars can be an imaging device in an electrophotographic printing machines, which are for example, linear substrates having an effective length equivalent to the width of the paper used, for example, letter size or A4 paper. In one embodiment, the raster image bar assembly 40 comprises any suitable image bar, for example, liquid crystal type image bars such as LED image bars addressed by appropriate control systems. The bar may be a write bar with an array of light sources without photosensors to create an image, as well as a bar to record an image. An exemplary image bar assembly used in electrophotographic copier/printer combination is described in U.S. Pat. No. 5,260,718, which disclosure is herein incorporated by reference in its entirety.
The media drive and imaging apparatus also comprises associated driving circuits. Exemplary circuits and image bars are disclosed in U.S. Pat. No. 5,260,718, which disclosure is incorporated herein by reference in its entirety. In embodiments illustrated herein the media drive and imaging apparatus is operatively configured to adapt to an power supply for providing the electricity to energize the system.
While the invention has been particularly shown and described with reference to a particular embodiment, it will be appreciated that variations of the above-disclosed embodiments and other features and functions, or alternatives thereof, may be desirably combined into many other different devices or applications. Also that various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.
