1. Field of the Invention
The present invention relates to a document feeding mechanism, particularly for the application of feeding a plurality of paper sheets one by one from a paper feed end of the automatic document feeder (ADF) and into an image input or output equipment by the ADF. The image input or output equipment includes a scanner, printer, imaging machine, and multi-function printer.
2. Prior Art
To improve convenience in use, the image input or output equipment can be equipped with an automatic document feeder. The automatic document feeder is used to feed a plurality of paper sheets from a paper cartridge one by one into a feeding path of the image input or output equipment for scanning or copying or printing.
The paper feeder end of the automatic document feeder is equipped with a feeder mechanism. The feeder mechanism is capable of feeding and separating paper sheets one by one from the paper cartridge to the paper feeder path.
As shown in
Since the document feeder mechanism 10 provide fixed friction force, when the thickness or the weight of paper to be fed is not fit in with the paper separating friction of the document feeder mechanism 10, then miss feeding or multiple feeding will occur.
In other words, automatic sheet separating efficiency can be assured if the automatic sheet separating mechanism is capable of providing proper friction to suit the thickness or weight of the paper sheets to be fed.
The objective of this invention is to provide a sheet separating mechanism with adjustable sheet separating force, to solve the problem of discrepancy between the friction of the sheet separating mechanism and the thickness or weight of the paper to be fed, thereby the automatic document feeding mechanism can achieve more accurate sheet separating efficiency.
Another objective of the present invention is to provide a document feeding mechanism with adjustable sheet separating force, thereby to achieve more accurate sheet separating efficiency, so that the user can reduce the time wasted in troubleshooting in case of miss feeding or multiple feeding during operation of the image input equipment or image output equipment.
To achieve the objectives and performance disclosed herein, the document feeding mechanism includes an auto document feeder (ADF) roller, a pad in close contact with the auto document feeding roller, and an elastic element exert a force to the pad, so that the pad contact with the ADF roller. Further an adjusting device connected with the elastic element for the purpose of adjusting the force of the elastic element on the pad, thereby the friction force between the pad and the ADF roller can be adjusted properly to enable accurate feeding of paper sheets of a different thickness or weight one by one in a smooth process.
Please refer to
The ADF roller 22 is combined with a turning shaft 28. The turning shaft 28 is driven and turned by a driving device (not shown in diagram), thereby simultaneously driving and turning the ADF roller 22.
The pad 24 is installed at one side of the ADF roller 22, forming an included angle with the ADF roller 22. Partial surface of the pad 24 is in contact with the outside surface of the ADF roller 22.
The elastic element 26 is installed at the bottom side of the pad 24. One end of the elastic element 26 is in connection with the bottom side of the pad 24, while the other end of the elastic element 26 is installed at the adjusting device 30.
The adjusting device 30 includes an adjusting unit 32 and a driving unit 34. The adjusting unit 32 is connected with one end of the elastic element 26. The driving unit 34 is connected with the adjusting unit 32. The driving unit 34 is used to drive the adjusting unit 32 to produce relative motion with the elastic element 26. Importantly, relative movement of the adjusting unit 32 and the elastic element 26 can achieve the change of deformation of the elastic element 26.
For example, the elastic element 26 is a spring, the adjusting unit 32 is a cam, and the driving unit 34 is a turning knob, wherein one end of the spring rests on the periphery of the cam.
When the user turns the driving unit 34 shown in
As far as the spring is concerned, the elasticity is in proportion to the deformation of the spring. When the deformation of the elastic element 26 increases, the force applied by the elastic element 26 on the pad 24 also increases. When the normal force between the pad 24 and the ADF roller 22 increases, the friction between the pad 24 and the ADF roller 22 increases accordingly. For paper having larger thickness or more weight, more friction will be more suitable for separating the paper sheets, enabling better efficiency in separating the paper sheets one by one. Conversely, adjusting of the adjusting device 30 to decrease the friction between the pad 24 and the ADF roller 22 will enable better efficiency for separating the paper sheets smaller thickness or lower weight.
Referring to
Before the paper is fed, at least one outside switch or software program can be used to control the driving unit 38, thereby producing relative movement of the adjusting unit 32 and the elastic element 26, and achieving the purpose of changing the elasticity of the elastic element 26.
Please refer to
Please refer to
The technical approach and anticipated objectives disclosed in the present invention can be concluded as follows:
1. The technical approach of the present invention is designed to change the elasticity of the elastic element 26, thereby changing the friction between the pad 24 and the ADF roller 22, so that the paper sheets having various thickness can be separated adequately with appropriate friction and fed into the automatic feeding device by the automatic sheet feeding mechanism.
2. The changing of the elasticity of the elastic element 26 is achieved by a set of adjusting device 30. The adjusting device 30 provides an adjusting unit 32 or 39. The adjusting unit 32 or 39 is capable of producing relative movement of the elastic element 26, changing the deformation of the elastic element 26, thereby reaching the purpose of adjusting the elasticity of the elastic element 26.
3. Using the design of the present invention, the appropriate feeding friction force can be adjusted during the automatic feeding process, to enhance the accuracy of the automatic feeding process, thereby reducing the time wasted in troubleshooting in incorrect or multiple feeding.
Although this invention has been disclosed and illustrated with reference to particular embodiments, the principles involved are susceptible for use in numerous other embodiments that will be apparent to persons skilled in the art. This invention is, there, to be limited only as indicated by the scope of the appended claim.
Number | Date | Country | Kind |
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094111346 | Apr 2005 | TW | national |