PAPER-FEEDING MECHANISM
The paper-feeding mechanism includes a duplex drive roller disposed on a terminal end of a feeding path of an image-forming device for feeding paper and on a side of an output tray, a first idle roller for conveying the paper back to the output tray with the duplex drive roller after a single side of the paper is printed, a second idle roller for conveying the paper back to the output tray with the duplex drive roller after double sides of the paper are printed, and a stop means installed between the terminal end of the feeding path and the output tray for switching to a shut position to stop the paper when the paper is driven back to the feeding path and for switching to an open position when the paper is driven to the output tray after the double sides of the paper are printed.
1. Field of the Invention
The present invention relates to a paper-feeding mechanism, and more particularly, to a paper-feeding mechanism capable of preventing paper from entering to a nip between a duplex drive roller and an idle roller incorrectly.
2. Description of the Prior Art
Image-forming devices with a duplex feeding function are widely used due to efficient utilization and cost down of paper. Please refer to
It is therefore a primary objective of the claimed invention to provide a paper-feeding mechanism capable of preventing paper from entering to a nip between a duplex drive roller and an idle roller incorrectly for solving the above-mentioned problem.
According to the claimed invention, the paper-feeding mechanism utilized for an image-forming device includes a duplex drive roller disposed on a terminal end of a feeding path of the image-forming device for feeding paper and on a side of an output tray, a first idle roller for conveying the paper back to the output tray with the duplex drive roller after a single side of the paper is printed, a second idle roller for conveying the paper back to the output tray with the duplex drive roller after double sides of the paper are printed, and a stop means installed between the terminal end of the feeding path and the output tray for switching to a shut position to stop the paper when the paper is driven back to the feeding path and for switching to an open position not to stop the paper when the paper is driven to the output tray after the double sides of the paper are printed.
These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.
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A hole 61 is disposed below the second idle roller 44 on the frame nearby the terminal end of the feeding path. There are two stop means 6 disposed on both sides of the second idle roller 44 and between the terminal end of the feeding path and the output tray 5. The stop means 6 is connected to a shaft 62. The stop means 6 includes a connecting part 68 fixed on the shaft 62, a top part 66, and an arched part 69 formed between the connecting part 68 and the top part 66. An arched cavity of the arched part 69 is disposed opposite to an exit direction of the paper. The stop means 6 can be paired to dispose preferredly.
The shaft 62 connected to the stop means 6 is pivoted inside the hole 61 in a rotatable manner. When the paper is not conveyed from the nip between the duplex drive roller 22 and the second idle roller 44, the stop means 6 is switched to a shut position. When the paper is conveyed from the nip between the duplex drive roller 22 and the second idle roller 44, the stop means 6 rotates around the shaft 62 to be switched from the shut position to an open position so as to convey the paper to the output tray 5.
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There is frictional force between paper S and the paper stack 13 on the output tray 5 because the paper S contacts with the paper stack 13 so that it is possible that the frictional force draws the paper S to the nip between the duplex drive roller 22 and the second idle roller 44 incorrectly resulting in a paper jam. Please refer to
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In contrast to the prior art, the present invention provides the restoring means to block the paper in front the nip between the duplex drive roller and the second idle roller when the frictional force between the paper and the paper stack draws the paper to the nip between the duplex drive roller and the second idle roller incorrectly so as to prevent the paper jam effectively.
Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention.
Claims
1. The paper-feeding mechanism utilized for an image-forming device comprising:
- a duplex drive roller disposed on a terminal end of a feeding path of the image-forming device and disposed on a side of an output tray for feeding paper;
- a first idle roller for conveying the paper to the output tray with the duplex drive roller after a single side of the paper is printed;
- a second idle roller for conveying the paper to the output tray with the duplex drive roller after double sides of the paper are printed; and
- a stop means installed between the terminal end of the feeding path and the output tray for switching to a shut position to stop the paper when the paper is driven back to the feeding path and for switching to an open position not to stop the paper when the paper is driven to the output tray after the double sides of the paper are printed.
2. The paper-feeding mechanism of claim 1 wherein the stop means is pivoted on the terminal end of the feeding path.
3. The paper-feeding mechanism of claim 1 further comprising a restoring means connected to the stop means for turning the stop means from the open position to the shut position.
4. The paper-feeding mechanism of claim 2 further comprising a shaft connected to the stop means and pivoted to the image-forming device for driving the stop means to rotate.
5. The paper-feeding mechanism of claim 3 wherein the restoring means is a torsional spring.
6. The paper-feeding mechanism of claim 5 wherein the torsional spring comprises:
- a pushing part contacting against the stop means; and
- a fixing part fixed on the image-forming device.
7. The paper-feeding mechanism of claim 3 wherein the restoring means is a weight stack.
8. The paper-feeding mechanism of claim 7 further comprising a shaft connected to the stop means and pivoted to the image-forming device for driving the stop means to rotate wherein the weight stack is connected to an end of the shaft.
9. The paper-feeding mechanism of claim 1 wherein the stop means comprises an arched part and an arched cavity of the arched part is disposed opposite to an exit direction of the paper.
Type: Application
Filed: May 25, 2008
Publication Date: Jul 30, 2009
Inventors: Tien-Ho Hsu (Hsinchu City), Chen-Tsai Tsai (Hsinchu City), Hsueh-Chou Hsu (Hsinchu County), Yu-Jen Tsao (Tai-Chung City)
Application Number: 12/126,923
International Classification: B65H 5/06 (20060101);