Patent Application
20070188818
This invention generally relates to imaging apparatus for documents and more particularly relates to an imaging apparatus having a tiltable paper path.
Providers of desktop and portable computer equipment and peripherals are keenly aware of the value of reducing the desktop space requirements of these devices. In particular, there are benefits to reducing the dimensional footprint for a peripheral document imaging apparatus such as a printer or scanner, particularly since such a device may be used intermittently in many environments.
The optical scanner for scanning and recording documents is one well-known type of imaging apparatus. An optical scanner typically includes a scanning station having an optical reading element, a light source, and a platen formed from glass or transparent plastic for maintaining the scanned portion of the document in a flat position. In operation, optical data from the document is transmitted from the optical reading element to one or to several buffer memories that temporarily store the data for further processing, typically with compression of the scan data. The optical scanner thus transforms text and image markings that have been recorded on the scanned document to image data, providing the image data as its output.
By comparison with an optical scanner, a printing apparatus operates in the complementary direction, transforming image data at its input to printed text and image markings that are recorded onto the sheet substrate to form the document. A variety of types of portable printers are used in desktop and workgroup printing environments, for imaging by forming a document onto a substrate. Portable printers in this general class include, for example, ink jet printers, laser printers, and thermal printers, along with other types of printers that could be used.
For conventional desktop-based document imaging applications, whether for scanning a document or for printing a document, relative movement is provided in some way between the document substrate, such as paper, and the image data transforming components that scan the substrate either for marking or for extracting an image. In one well-known type of imaging apparatus, the flatbed scanner, the document remains stationary on a transparent platen and an optical reading element, mounted on a movable carriage assembly on the other side of the platen, travels along the length of the platen to scan the document sheet. However, with most types of desktop and workgroup imaging apparatus, both printers and scanners alike, the alternative “sheet-fed” model applies.
Using sheet-fed design, the image data transformation apparatus is stationary and the document sheet is scanned past the image data transformation apparatus, either for image recording or for optical scanning. Sheet-fed operation has advantages for automated operation and compactness in many applications and is well suited to line-by-line image sensing by a linear array of optical sensors in a scanner, as well as to line-by-line marking by a linear or linearly actuated printhead. A sheet-fed imaging apparatus can be used to scan or print single sheet documents or to successively pull one sheet at a time from a stack of sheets for scanning or printing, making this device better suited for applications where volume is important.
Both desktop scanners and desktop printers operate in document imaging environments where space or footprint is at a premium. Proposed solutions for reducing the space requirements for typical document imaging devices include the following:
As one example, a reduced-footprint sheet-fed scanner, the DR-2050C scanner from Canon Electronics Inc., Saitama, Japan, has been introduced for desktop environments. In this device, the paper travel path is generally vertical, unlike conventional types of sheet-fed scanners. This vertical orientation may be acceptable for single-sheet scanning and for front-loading. However, the vertical paper path orientation is inherently disadvantaged for sheet feeding from a stack of sheets, particularly if the stack has sheets of varying thickness, for longer length sheets, where there are creases or inherent curl to the sheets, or where the paper stock for one or more sheets is relatively thin. Documents can tip over or even fall out of the feed tray when vertically oriented. Where sheets exit a paper handling mechanism at a steep vertical angle, there is tendency to curl. This tendency may not pose a problem when scanning a single sheet, but is increasingly cumbersome where a stack of sheets must be scanned, causing exiting sheets to jam together and to be out of order or skewed, often requiring manual resorting or other operator intervention. The use of an output tray is not optimal with paper exit at a steep angle. This same principle also applies for document printing. For applications in which only a single document is printed, a vertical paper path might easily be acceptable, particularly where the operator is standing by to obtain the printed document. However, where multiple sheet documents are printed or for applications where document output order is important, the vertical paper path is not desirable; instead, a paper path oriented toward horizontal is much preferred for printing multiple pages.
Thus, there are good reasons why, in conventional practice, sheet-fed document imaging systems maintain the stack of paper at an angle close to horizontal: paper handling works most smoothly where the stack of sheets lie atop each other at such an inclination. By contrast, paper path orientation at or close to vertical makes the task of paper handling considerably more complex and trouble-prone when scanning more than one sheet or longer sheets.
The demands on the paper handling components are heightened with the pressure to improve desktop scanner and printer performance and provide faster document processing speeds. As one illustration of this trend, efforts are underway to provide workgroup scanners with faster paper handling, using solutions that had been previously applied for higher volume production scanners. For example, where conventional workgroup scanners perform gray-scale scanning in the range of about 20 pages per minute (PPM) on average, it is conceivable that improvements in paper handling and in scanning optics will allow this speed to increase more than two-fold. In order to make this happen, however, the paper handling must be robust, providing output stacking in order, minimizing curl, jams, or other problems.
While footprint and capability for robust paper handling are important, ergonomic factors can also be considered. Where an operator performs a single-page scan or prints a single document, the more natural position is facing the imaging apparatus, with a vertical orientation being quite satisfactory. With the scan or print job taking a few seconds at most, the operator can wait to retrieve a single exiting document. However, where a stack of multiple pages is to be scanned or printed, feeding of the stack from the opposite or rear side of the scanner is more natural, particularly where document sheets may have different sizes or thicknesses. For example, an operator may load a set of documents for scanning, then be otherwise occupied during at least part of the scan, unwilling to stand by to resort individual documents that get out of order due to high exit feed angles. Or, a multi-page print job can be initiated over a network, where sheets feed automatically and where providing printed documents that are stacked in order is preferable.
With recent developments in banking and communications and ever increasing numbers of electronic transactions, it seems clear that desktop document imagers for departmental, workgroup, and consumer market segments will become increasingly more important, with impetus for improved overall performance, including increased speeds and more reliable paper handling. At the same time, desktop workspace remains at a premium in many work environments. There is thus a need for a flexible document imager solution that allows improved performance while minimizing device footprint.
Briefly, according to one aspect of the present invention, a document imaging apparatus comprising an imager body that houses:
It is a feature of the present invention that the paper path tilt angle adjusts to a position selectable by an operator.
It is an advantage of the present invention that it allows adjustment of the tilt angle for single- or multiple-document feeding while maintaining a small dimensional footprint.
These and other objects, features, and advantages of the present invention will become apparent to those skilled in the art upon a reading of the following detailed description when taken in conjunction with the drawings wherein there is shown and described an illustrative embodiment of the invention.
While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter of the present invention, it is believed that the invention will be better understood from the following description when taken in conjunction with the accompanying drawings, wherein:
The present description is directed in particular to elements forming part of, or cooperating more directly with, apparatus in accordance with the invention. It is to be understood that elements not specifically shown or described may take various forms well known to those skilled in the art.
The term “document imaging apparatus” as used herein refers to the large class of devices that are either used for recording document data in either of two directions: (i) recording images and other types of human-readable information onto a sheet of substrate to form a document according to image data, or (ii) obtaining and recording machine-readable image data from a document sheet by optical scanning. Devices for recording human-readable information onto a document sheet include various types of printer apparatus, such as inkjet, thermal, photographic, laser, and line printers, for example. Devices for obtaining and recording machine-readable image data are generally classified as scanners.
It is instructive to note that there are a number of devices that may use a scanner, as the term is used with respect to the present invention. The term scanner generally applies to a device that optically scans a document to obtain and record machine-readable image data signals representative of the content of the document. The term scanner thus comprises not only the various types of flat platen and paper feed desktop scanners described in the Background section given earlier, but also comprises applicable portions of facsimile apparatus, commonly called fax machines, copier apparatus, and other similar devices, including devices that combine these image capture, reproduction, and transmission functions. Numerous types of sheet documents can be scanned, including items such as text documents and forms, banking and legal transaction documents, applications, photographs and other images, artwork, and identification documents such as credit cards, driver's licenses, ID badges, and the like. Similarly, while the present invention applies to a printer, it also applies to a device that includes a printing or marking apparatus as a component, such as facsimile apparatus, for example.
As is shown in the block diagram of
Referring to the perspective view of
The arrangement of imager body 12 pivotably coupled to support pedestal 20 is particularly advantaged for allowing easy access to internal document imaging apparatus components along the paper path. The side view of
In terms of information flow, image data transformation apparatus 34 may operate in one of two directions to record document data, either to extract image data for recording from an image or to record an image from image data by printing or marking the document in some manner. For either printing or optical sensing embodiments, the document is moved at a controlled speed past image data transformation apparatus 34 where the transformation to or from image data occurs. In one alternate embodiment, where document imaging apparatus 10 is a printer, image data transformation apparatus 34 may be a marking module or element for recording an image, such as a printhead. Typically, only one printhead is used so that a single image data transformation apparatus 34 would be provided for a printer; however, a two-sided printing embodiment could employ first and second image data transformation apparatus 34 as printheads, as shown in
A paper feed apparatus 36 provides single-sheet feeding for documents fed from paper feed input source 14. Paper feed apparatus 36 may urge document sheets for scanning along the paper path using a clutched feed drive, for example. With the hinged arrangement shown, these internal optical and paper feeding components, along with other components such as start-of-sheet/end-of-sheet sensors and auxiliary rollers for example, can be easily accessed for cleaning, clearing jams, or checking operation.
The side views of
In
In the position shown in
In the position of
Output tray 32 can be positioned or seated in any of a number of positions. In one embodiment, output tray 32 can be fitted beneath support pedestal 20; this would be an advantageous arrangement at the near-vertical orientation of
Pivoting mechanism 22 can take any of a number of forms. In the embodiment of
Possible alternatives to latch mechanism 42 include various types of tightening mechanisms that would allow continuous adjustment of tilt angle, rather than discrete, fixed-position adjustment. As one alternative, shown in the perspective view of
When imager body 12 is configured as a printer body, the apparatus and method of the present invention are compatible with printheads that form a line of the image at a time. When imager body 12 is configured as a scanner body, the apparatus and method of the present invention are compatible with scanning optics of various types, including components using CCD or CMOS sensors for high speed and lower cost or those using the more expensive and slower contact arrays.
The invention has been described in detail with particular reference to certain preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the scope of the invention as described above, and as noted in the appended claims, by a person of ordinary skill in the art without departing from the scope of the invention. For example, a variety of paper handling components could be used for urging the document sheet along paper path P as part of paper feed apparatus 36. Either single-side or duplex scanning or printing can be provided, as well as both printing and scanning functions, each provided using a separate image data transformation apparatus 34.
As noted earlier, document imaging apparatus 10 could be used to scan or print a full range of media types. Document sheets can be any of a number of types of materials, including paper, plastic, and hybrid combinations of paper and plastic, for example. Document sheet materials could be of various sizes and could be transparent, opaque, photosensitive, or have other suitable properties. Tilt angle adjustment of imager body 12 could be effected using any of a number of different types of pivoting mechanisms 22, including automated mechanisms that set or reset tilt position according to programmed instructions or to sensed conditions, such as document type, paper stack thickness, or timeouts, for example.
Thus, what is provided is a document imaging apparatus having a tiltable paper path.
