BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more fully understood from the detailed description given herein below for illustration only, which thus is not limitative of the present invention, and wherein:
FIG. 1 is a perspective view of an embodiment of the present invention.
FIG. 2 is a top view of the embodiment of the present invention.
FIGS. 3 and 4 are enlarged schematic views of parts of the embodiment of the present invention.
FIG. 5 is a top view of the embodiment of the present invention in another aspect.
DETAILED DESCRIPTION OF THE INVENTION
The driving roller assembly provided by the present invention is applied in a paper feeding apparatus, which can be but not limited to printers, paper-feeding scanners, or multifunctional printers.
FIGS. 1 and 2 are respectively a perspective view and a top view of an embodiment of the present invention. A first driving roller 210 and a second driving roller 220 are disposed in the paper feeding apparatus with a rotational axis parallel to that of each other. The first driving roller 210 is a part of a paper-grabbing roller set of the paper feeding apparatus, and the second driving roller 220 is a part of a driven roller set of the paper feeding apparatus. The first driving roller 210 is provided for grabbing a piece of paper 700 from a paper- tray (not shown), and conveying the piece of paper 700 to the second driving roller 220. The second driving roller 220 is provides for receiving the piece of paper 700 conveyed by the first driving roller and then conveying the piece of paper, such that the piece of paper is continuously conveyed in a paper track of the paper feeding apparatus. Generally, the rotational speed of the second driving roller 220 is higher than that of the first driving roller 210, such that a fixed interval is formed between the two pieces of paper due to the rotational speed difference. When the front edge of the paper 700 reaches the second driving roller 220, the driving power output for the first driving roller 210 is stopped.
The driving roller assembly of the present invention is provided for driving the first driving roller 210 rotating about a rotational axis X. A shaft is disposed at the rotational axis X of the first driving roller 210, so as to fix the first driving roller 210 to a predetermined position corresponding to an inlet of the paper track of the paper feeding apparatus. The driving roller assembly includes a transmitting sleeve 400, a one-way coupling sleeve 500, and a driven block 600. The details are described as follows.
Referring to FIGS. 3 and 4, the transmitting sleeve 400 is slid over the shaft 300, and has a canted edge 410 formed at one end thereof and a driven part 430 opposite the canted edge 400 formed at the other end of the transmitting sleeve 400. The canted edge 410 has an inclined angle with respect to the rotational axis X. One end of the canted edge 410 extending towards outside of the transmitting sleeve 400 along the rotational axis X is formed into a first stopper 421, and the other end of the canted edge 410 extending towards inside of the transmitting sleeve 400 along the rotational axis X is formed into a second stopper 422. A notch 420 is formed between the first stopper 421 and the second stopper 422, and the canted edge 410 is just located within the notch 420. The driven part 430 can be a gear for connecting to a first driving device 920 (e.g., a motor), such that the transmitting sleeve 400 is driven by the first driving device 920.
The one-way coupling sleeve 500 is slid over the shaft 300, and has a first one-way coupling end 510 and an actuating end 520. A slide block 521 is protruded from the actuating end 520, which is slidably contacted with the canted edge 421 and to presses against the first stopper 421. When the transmitting sleeve 400 rotates along a first rotational direction, the actuating end 520 slides relative to the canted edge 410, and moves the one-way coupling sleeve 500 to away from the transmitting sleeve 400 along the rotational axis X, and the first stopper 421 presses against the slide block 521 of the actuating end 520, such that the actuating end 520 is engaged with the first stopper 421 and then the transmitting sleeve 400 drives the one-way coupling sleeve 500 to rotate. When the transmitting sleeve 400 rotates along a second rotational direction opposite to the first rotational direction, the one-way coupling sleeve 500 is released and not rotated.
The driven block 600 is fixed to the shaft 300, and has a second one-way Coupling end 620 corresponding to the first one-way coupling end 510 of the one-way coupling sleeve 500. The first one-way coupling end 510 is coupled to the second one-way coupling end 620 in one rotational direction only, such that the one-way coupling sleeve 500 is coupled to the driven block 600 to drive the shaft 300 to rotate in one rotational direction only. Specifically in the embodiment of the present invention, the first one-way coupling end 510 is coupled to the second one-way coupling end 620 in the first rotational direction, and it is released from the second one-way coupling end 620 in the second rotational direction opposite to the first rotational direction. Therefore, when the one-way coupling sleeve 500 rotates in the first rotational direction, it drives the driven block 600; and when the one-way coupling sleeve 500 rotates in the second rotational direction, it doesn't move together with the driven block 600. When the one-way coupling sleeve 500 rotates in the first rotational direction together with the transmitting sleeve 400, the one-way coupling sleeve 500 is moved away from the transmitting sleeve 400, such that the first one-way coupling end 510 presses against the second one-way coupling end 620, and the first one-way coupling end 510 and the second one-way coupling end 620 are coupled with each other in the first rotating direction, as shown in FIG. 4.
Referring to FIGS. 2, 3, and 5, FIG. 5 shows the cooperation of the first driving roller 210 and the second driving roller 220. The first driving device 920 is connected to the driven part 430, and further drives the transmitting sleeve 400 to rotate, and moves the one-way coupling sleeve 500 to be coupled to the driven block 600, and thereby driving the first driving roller 210 to rotate. At meanwhile, the piece of paper 700 is conveyed by the first driving roller 210 towards the second driving roller 220. A trigger element 800 is disposed in advance of the second driving roller 220 for detecting the arrival of the front edge of the piece of paper 700 to be received by the second driving roller. Once the front edge of the paper 700 is detected by the trigger element 800, a second driving device 940 immediately outputs power to drive the second driving roller 220 to rotate. At the same time, the first driving device 920 is stopped driving the transmitting sleeve 400. In the paper feeding apparatus, the paper feeding rate of the second driving roller 220 must be higher than that of the first driving roller 200, or when the second driving roller 220 is contacted with the paper 700, the first driving device 920 must be stopped. The first driving roller 210 is driven by the piece of paper 700 and rotates at a speed higher than the speed of the transmitting sleeve 400, thus, the driven block 600 rotates in the second rotational direction relative to the one-way coupling sleeve 500 and the transmitting sleeve 400. Thus, the driven block 600 is not coupled to the one-way coupling sleeve 500, such that the rotation of the driven block 600 doesn't interfere with the first driving device 920, the transmitting sleeve 400, and the one-way coupling sleeve 500. Accordingly, the paper 700 is conveyed into the paper feeding apparatus through the second driving device 940 and the second driving roller 220 at a speed higher than the paper feeding rate of the first driving roller 200. The predetermined interval between two pieces of paper can be maintained due to the different speeds for the first driving roller 210 and the second driving roller 220 to convey the piece of paper 700.
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious-to one skilled in the art are intended to be included within the scope of the following claims.
Patent Application
20080023903
