U.S. patent application number 10/657154 was filed with the patent office on 2004-10-14 for automatic sheet feeder.
Invention is credited to Chen, Chi-Yao, Sheng, Thomas.
Application Number | 20040201159 10/657154 |
Document ID | / |
Family ID | 33129501 |
Filed Date | 2004-10-14 |
United States Patent
Application |
20040201159 |
Kind Code |
A1 |
Sheng, Thomas ; et
al. |
October 14, 2004 |
Automatic sheet feeder
Abstract
An automatic sheet feeder includes a sheet input tray, first to
third passageways, through which sheets may be successively fed, a
sheet-feeding mechanism, and a sheet output tray. The first
passageway communicates with the sheet input tray, the second
passageway selectively communicates with the first passageway, and
the third passageway selectively communicates with the first
passageway. The sheet-feeding mechanism feeds a first sheet
successively from the sheet input tray to the first, second, first,
and third passageways. The sheet output tray, in which the sheets
are stored, communicates with the third passageway. The front side
of the first sheet is toward opposite directions when it passes
through the first passageway at the first and second times. When
the first sheet is fed to the third passageway, a second sheet is
fed to the first passageway.
Inventors: |
Sheng, Thomas; (Hsinchu,
TW) ; Chen, Chi-Yao; (Hsin Chu City, TW) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Family ID: |
33129501 |
Appl. No.: |
10/657154 |
Filed: |
September 9, 2003 |
Current U.S.
Class: |
271/3.14 |
Current CPC
Class: |
B65H 29/60 20130101;
B65H 5/06 20130101 |
Class at
Publication: |
271/003.14 |
International
Class: |
B65H 005/22 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 14, 2003 |
TW |
092205849 |
Claims
What is claimed is:
1. An automatic sheet feeder, comprising: a sheet input tray for
storing a plurality of sheets including a first sheet and a second
sheet, each of the sheets having a front side and a back side; a
first passageway, a second passageway, and a third passageway,
through which the sheets may be successively fed, the first
passageway communicating with the sheet input tray, a first end of
the second passageway selectively communicating with the first
passageway, a second end of the second passageway communicating
with the first passageway, and the third passageway selectively
communicating the first passageway; a sheet-feeding mechanism
having a duplex sheet-feeding mode for feeding the first sheet
successively from the sheet input tray to the first passageway, the
second passageway, the first passageway, and the third passageway;
and a sheet output tray, in which the sheets are stored,
communicating with the third passageway, wherein in the duplex
sheet-feeding mode, the front side of the first sheet is toward
opposite directions when it passes through the first passageway at
first and second times, and when the first sheet is fed to the
third passageway, the second sheet is fed to the first
passageway.
2. The automatic sheet feeder according to claim 1, wherein the
first passageway comprises: a main passageway communicating with
the sheet input tray; a first sub-passageway communicating with the
main passageway and the second passageway; a second sub-passageway
communicating with the main passageway and the third passageway;
and a main/sub-passageway guiding rod for switchably guiding the
first sheet from the main passageway through the first
sub-passageway or the second sub-passageway.
3. The automatic sheet feeder according to claim 2, further
comprising: a first temporary storage region selectively
communicating with the first sub-passageway and the second
passageway, the first sheet from the first sub-passageway being
temporarily stored in the first temporary storage region; and a
first guiding rod for switchably guiding the first sheet from the
first sub-passageway to the first temporary storage region, and
guiding the first sheet from the first temporary storage region to
the second passageway.
4. The automatic sheet feeder according to claim 3, further
comprising: a second temporary storage region selectively
communicating with the second sub-passageway and the third
passageway, the first sheet from the second sub-passageway being
temporarily stored in the second temporary storage region; and a
second guiding rod for switchably guiding the first sheet from the
second sub-passageway to the second temporary storage region, and
guiding the first sheet from the second temporary storage region to
the third passageway.
5. The automatic sheet feeder according to claim 4, wherein the
main passageway is formed with an image processing region.
6. The automatic sheet feeder according to claim 5, further
comprising a scanning module opposite to the image processing
region for scanning the first sheet passing through the image
processing region.
7. The automatic sheet feeder according to claim 5, further
comprising a printing module opposite to the image processing
region for printing the first sheet passing through the image
processing region.
8. The automatic sheet feeder according to claim 5, wherein the
sheet-feeding mechanism comprises: a sheet-input roller for feeding
the first sheet from the sheet input tray to the main passageway; a
first roller set located on the main passageway for assisting in
feeding the first sheet from the sheet input tray to the first
sub-passageway, and assisting in feeding the first sheet from the
second passageway to the second sub-passageway; a second roller set
for feeding the first sheet from the first sub-passageway to the
first temporary storage region, and feeding the first sheet from
the first temporary storage region to the second passageway; a
third roller set for feeding the first sheet from the second
sub-passageway to the second temporary storage region, and feeding
the first sheet from the second temporary storage region to the
third passageway; and a sheet-output roller set for feeding the
first sheet from the third passageway to the sheet output tray.
9. The automatic sheet feeder according to claim 1, further
comprising: a temporary storage region selectively communicating
with the first passageway and the second passageway, the first
sheet of the first passageway being temporarily stored in the
temporary storage region; and a first guiding rod for switchably
guiding the first sheet from the first passageway to the temporary
storage region, and guiding the first sheet from the temporary
storage region to the second passageway.
10. The automatic sheet feeder according to claim 9, further
comprising: a second guiding rod for switchably guiding the first
sheet from the first passageway to the temporary storage region or
the third passageway.
11. The automatic sheet feeder according to claim 10, wherein the
first passageway is formed with an image processing region.
12. The automatic sheet feeder according to claim 10, further
comprising a scanning module opposite to the image processing
region for scanning the first sheet passing through the image
processing region.
13. The automatic sheet feeder according to claim 10, further
comprising a printing module opposite to the image processing
region for printing the first sheet passing through the image
processing region.
14. The automatic sheet feeder according to claim 10, wherein the
sheet-feeding mechanism comprises: a sheet-input roller for feeding
the first sheet from the sheet input tray to the first passageway;
a first roller set and a second roller set located on the first
passageway for assisting in feeding the first sheet from the sheet
input tray to the temporary storage region, and assisting in
feeding the first sheet from the second passageway to the third
passageway; a third roller set for feeding the first sheet from the
first passageway to the temporary storage region and feeding the
first sheet from the temporary storage region to the second
passageway; a fourth roller set for feeding the first sheet from
the first passageway to the third passageway; a fifth roller set
located on the third passageway for assisting in feeding the first
sheet from the third passageway to the sheet output tray; and a
sheet-output roller set for feeding the first sheet to the sheet
output tray.
15. The automatic sheet feeder according to claim 14, wherein the
third roller set and the fourth roller set share one roller.
16. The automatic sheet feeder according to claim 1, wherein the
sheet-feeding mechanism further has a simplex sheet-feeding mode,
in which the sheet-feeding mechanism feeds the first sheet from the
sheet input tray through the first passageway and finally to the
sheet output tray, a relative order between the first sheet and the
second sheet is kept unchanged after the sheets are fed in the
simplex sheet-feeding mode or the duplex sheet-feeding mode.
17. An automatic sheet feeder, comprising: a sheet input tray for
storing a plurality of sheets including a first sheet and a second
sheet, each of the sheets having a front side and a back side; a
sheet output tray for storing the sheets after being fed; a first
passageway and a second passageway, through which the sheets may be
successively fed, the first passageway communicating with the sheet
input tray, a first end of the second passageway selectively
communicating with the first passageway, and a second end of the
second passageway communicating with the first passageway; and a
sheet-feeding mechanism for feeding the first sheet successively
from the sheet input tray through the first passageway, the second
passageway and the first passageway, and finally to the sheet
output tray.
18. The automatic sheet feeder according to claim 17, wherein the
first passageway comprises: a main passageway communicating with
the sheet input tray; a first sub-passageway communicating with the
main passageway and the second passageway; a second sub-passageway
communicating with the main passageway and the sheet output tray;
and a main/sub-passageway guiding rod for switchably guiding the
first sheet from the main passageway through the first
sub-passageway or the second sub-passageway.
19. The automatic sheet feeder according to claim 18, further
comprising: a temporary storage region, which selectively
communicates with the first sub-passageway and the second
passageway, for temporarily storing the first sheet from the first
sub-passageway; and a first guiding rod for switchably guiding the
first sheet from the first sub-passageway to the temporary storage
region, and guiding the first sheet from the temporary storage
region to the second passageway.
20. The automatic sheet feeder according to claim 19, wherein the
main passageway is formed with an image processing region.
21. The automatic sheet feeder according to claim 20, further
comprising a scanning module opposite to the image processing
region for scanning the first sheet passing through the image
processing region.
22. The automatic sheet feeder according to claim 20, further
comprising a printing module opposite to the image processing
region for printing the first sheet passing through the image
processing region.
23. The automatic sheet feeder according to claim 20, wherein the
sheet-feeding mechanism comprises: a sheet-input roller for feeding
the first sheet from the sheet input tray to the main passageway; a
first roller set located on the main passageway for assisting in
feeding the first sheet from the sheet input tray to the first
sub-passageway, and assisting in feeding the first sheet from the
second passageway to the second sub-passageway; a second roller set
for feeding the first sheet from the first sub-passageway to the
temporary storage region, and feeding the first sheet from the
temporary storage region to the second passageway; and a
sheet-output roller set for feeding the first sheet from the second
sub-passageway to the sheet output tray.
24. The automatic sheet feeder according to claim 17, further
comprising: a temporary storage region, which selectively
communicates with the first passageway and the second passageway,
for temporarily storing the first sheet from the first passageway;
and a first guiding rod for switchably guiding the first sheet from
the first passageway to the temporary storage region, and guiding
the first sheet from the temporary storage region to the second
passageway.
25. The automatic sheet feeder according to claim 24, further
comprising: a second guiding rod for switchably guiding the first
sheet from the first passageway to the temporary storage region or
the sheet output tray.
26. The automatic sheet feeder according to claim 25, wherein the
first passageway is formed with an image processing region.
27. The automatic sheet feeder according to claim 25, further
comprising a scanning module opposite to the image processing
region for scanning the first sheet passing through the image
processing region.
28. The automatic sheet feeder according to claim 25, further
comprising a printing module opposite to the image processing
region for printing the first sheet passing through the image
processing region.
29. The automatic sheet feeder according to claim 25, wherein the
sheet-feeding mechanism comprises: a sheet-input roller for feeding
the first sheet from the sheet input tray to the first passageway;
a first roller set and a second roller set located on the first
passageway for assisting in feeding the first sheet from the sheet
input tray to the temporary storage region, and assisting in
feeding the first sheet from the second passageway to the sheet
output tray; and a sheet-output roller set for feeding the first
sheet from the first passageway to the sheet output tray.
30. The automatic sheet feeder according to claim 29, wherein the
second roller set and the sheet-output roller set share one
roller.
31. The automatic sheet feeder according to claim 24, wherein the
sheet-feeding mechanism comprises: a sheet-input roller for feeding
the first sheet from the sheet input tray to the first passageway;
a first roller set located on the first passageway for assisting in
feeding the first sheet from the sheet input tray to the temporary
storage region, and assisting in feeding the first sheet from the
second passageway to the temporary storage region; and a
sheet-output roller set for feeding the first sheet from the first
passageway to the temporary storage region, feeding the first sheet
temporarily stored in temporary storage region to the second
passageway, feeding the first sheet from the second passageway and
the first passageway to the temporary storage region, and then
releasing the first sheet to let it fall down to the sheet output
tray.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to an automatic sheet feeder, and more
particularly to an automatic sheet feeder applied to a duplex image
input/output apparatus.
[0003] 2. Description of the Related Art
[0004] A conventional duplex scanner usually has an automatic sheet
feeder to turn over a document three times and feed the document
through a scan region three times. When the document passes through
the scan region at the first time, its front side is scanned. When
the document passes through the scan region at the second time, its
back side is scanned. When the document passes through the scan
region in the third time, the scanner performs no scan operation
because the third sheet-feeding operation is performed such that
the document is arranged to return to its original order.
[0005] Consequently, in each scan procedure for one document, it is
necessary to wait for the document to thirdly pass through the scan
region and then to feed a next document for scan. The conventional
automatic sheet feeder wastes a lot of unnecessary waiting time
such that the scan operations cannot be performed rapidly.
SUMMARY OF THE INVENTION
[0006] It is therefore an object of the invention to provide an
automatic sheet feeder capable of accelerating the duplex image
processing procedures and meeting the simplex image processing
procedures.
[0007] In order to achieve the above-mentioned object, the
invention provides an automatic sheet feeder including a sheet
input tray, a first passageway, a second passageway, a third
passageway, a sheet-feeding mechanism and a sheet output tray. The
sheet input tray is used to store a plurality of sheets including a
first sheet and a second sheet, and each of the sheets has a front
side and a back side. The sheets may pass through the first to
third passageways one by one.
[0008] The first passageway communicates with the sheet input tray,
a first end of the second passageway selectively communicates with
the first passageway, a second end of the second passageway
communicates with the first passageway, and the third passageway
selectively communicates with the first passageway. The
sheet-feeding mechanism feeds the first sheet successively from the
sheet input tray to the first passageway, the second passageway,
the first passageway, and the third passageway. The sheet output
tray, in which the sheets are stored, communicates with the third
passageway. The front side of the first sheet is toward opposite
directions when it passes through the first passageway at the first
and second times. When the first sheet is fed to the third
passageway, the second sheet is fed to the first passageway.
[0009] According to the above-mentioned configuration, it is
possible to image-process (e.g., scan or print) the second sheet at
the time when the first sheet passes through the third
passageway.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 shows a first state of an automatic sheet feeder
according to a first embodiment of the invention.
[0011] FIG. 2 shows a second state of the automatic sheet feeder
according to the first embodiment of the invention.
[0012] FIG. 3 shows a third state of the automatic sheet feeder
according to the first embodiment of the invention.
[0013] FIG. 4 shows a fourth state of the automatic sheet feeder
according to the first embodiment of the invention.
[0014] FIG. 5 shows an automatic sheet feeder according to a second
embodiment of the invention.
[0015] FIG. 6 shows a first state of an automatic sheet feeder
according to a third embodiment of the invention.
[0016] FIG. 7 shows a second state of the automatic sheet feeder
according to the third embodiment of the invention.
[0017] FIG. 8 shows a third state of the automatic sheet feeder
according to the third embodiment of the invention.
[0018] FIG. 9 shows a fourth state of the automatic sheet feeder
according to the third embodiment of the invention.
[0019] FIG. 10 shows a first state of an automatic sheet feeder
according to a fourth embodiment of the invention.
[0020] FIG. 11 shows a second state of the automatic sheet feeder
according to the fourth embodiment of the invention.
[0021] FIG. 12 shows a third state of the automatic sheet feeder
according to the fourth embodiment of the invention.
[0022] FIG. 13 shows a fourth state of the automatic sheet feeder
according to the fourth embodiment of the invention.
[0023] FIG. 14 shows a first state of an automatic sheet feeder
according to a fifth embodiment of the invention.
[0024] FIG. 15 shows a second state of the automatic sheet feeder
according to the fifth embodiment of the invention.
[0025] FIG. 16 shows a first state of an automatic sheet feeder
according to a sixth embodiment of the invention.
[0026] FIG. 17 shows a second state of the automatic sheet feeder
according to the sixth embodiment of the invention.
[0027] FIG. 18 shows an automatic sheet feeder according to a
seventh embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0028] FIGS. 1 to 4 show several states of an automatic sheet
feeder according to a first embodiment of the invention,
respectively. As shown in FIG. 1, the automatic sheet feeder is
applied to a sheet-fed scanner. However, in other embodiments, the
automatic sheet feeder also may be combined with a flatbed scanner,
or applied to a printer. The automatic sheet feeder includes a
sheet input tray 10, a first passageway 12, a second passageway 14,
a third passageway 16, a sheet-feeding mechanism 30, and a sheet
output tray 50.
[0029] The sheet input tray 10 is used to store a plurality of
sheets including a first sheet P1 and a second sheet P2. Each of
the sheets has a front side and a back side. For example, the first
sheet P1 has a front side P1A and a back side P1B.
[0030] The sheets may be successively fed through the first
passageway 12, the second passageway 14 and the third passageway 16
one by one. The first passageway 12 communicates with the sheet
input tray 10. A first end 14A of the second passageway 14
selectively communicates with the first passageway 12, and a second
end 14B of the second passageway 14 communicates with the first
passageway 12. The third passageway 16 selectively communicates
with the first passageway 12.
[0031] The sheet-feeding mechanism 30 feeds the first sheet P1
successively from the sheet input tray 10 to the first passageway
12, the second passageway 14, the first passageway 12, and the
third passageway 16.
[0032] The sheet output tray 50, in which the sheets are stored,
communicates with the third passageway 16. In order to increase the
sheet-feeding speed, the automatic sheet feeder of the invention is
configured such that the front side P1A of the first sheet P1 is
toward opposite directions when it passes through the first
passageway 12 at the first and second times. In addition, when the
first sheet P1 is fed into the third passageway 16, the second
sheet P2 is fed into the first passageway 12.
[0033] In the embodiment, the first passageway 12 includes a main
passageway 12A, a first sub-passageway 12B, a second sub-passageway
12C, and a main/sub-passageway guiding rod 12D. The main passageway
12A communicates with the sheet input tray 10, the first
sub-passageway 12B communicates with the main passageway 12A and
the second passageway 14, and the second sub-passageway 12C
communicates with the main passageway 12A and the third passageway
16. The main/sub-passageway guiding rod 12D switchably guides the
first sheet P1 from the main passageway 12A to pass through the
first sub-passageway 12B or the second sub-passageway 12C.
[0034] The automatic sheet feeder of the embodiment further
includes a first temporary storage region 22, a first guiding rod
26, a second temporary storage region 24, and a second guiding rod
28. The first temporary storage region 22, in which the first sheet
P1 from the first sub-passageway 12B is temporarily stored,
selectively communicates with the first sub-passageway 12B and the
second passageway 14. The first guiding rod 26 switchably guides
the first sheet P1 from the first sub-passageway 12B to the first
temporary storage region 22, and guides the first sheet P1 from the
first temporary storage region 22 to the second passageway 14. The
second temporary storage region 24, in which the first sheet P1
from the second sub-passageway 12C is temporarily stored,
selectively communicates with the second sub-passageway 12C and the
third passageway 16. The second guiding rod 28 switchably guides
the first sheet P1 from the second sub-passageway 12C to the second
temporary storage region 24, and guides the first sheet P1 from the
second temporary storage region 24 to the third passageway 16.
[0035] In addition, an image processing region 20 is formed on the
main passageway 12A. In the so-called image processing region 20,
an image processing module opposite to the image processing region
20 may perform image processing on the sheet passing through the
region 20. For example, the first sheet P1 may be scanned by a
scanning module 60 including an image sensor 61 and a reflecting
mirror 62, or may be printed by a printing module (not shown).
[0036] In the embodiment, the sheet-feeding mechanism 30 includes a
sheet-input roller 31, first to third roller sets 32 to 34, and a
sheet-output roller set 39. The sheet-input roller 31 feeds the
first sheet P1 from the sheet input tray 10 to the main passageway
12A. The first roller set 32 is located on the main passageway 12A
to assist in feeding the first sheet P1 from the sheet input tray
10 to the first sub-passageway 12B. The front side P1A of the first
sheet P1 faces downward in the image processing region 20, and is
scanned by the scanning module 60.
[0037] At this time, the main/sub-passageway guiding rod 12D swings
downward to connect the first sub-passageway 12B with the main
passageway 12A and disconnect the second sub-passageway 12C from
the main passageway 12A. In addition, the first guiding rod 26
swings upward to enable the second roller set 33 to feed the first
sheet P1 from the first sub-passageway 12B to the first temporary
storage region 22.
[0038] Referring next to FIG. 2, after the first sheet P1 has left
the first sub-passageway 12B, the second roller set 33 is reversed
and the first guiding rod 26 swings downward so that the second
roller set 33 may feed the first sheet P1 from the first temporary
storage region 22 to the second passageway 14. Then, the first
sheet P1 enters the main passageway 12A from the second end 14B of
the second passageway 14, the back side P1B of the first sheet P1
in the image processing region 20 faces downward (the front side
P1A faces upward) and is scanned by the scanning module 60.
[0039] Referring next to FIG. 3, the main/sub-passageway guiding
rod 12D swings upward so that the first roller set 32 may assist in
feeding the first sheet P1 from second passageway 14 to the second
sub-passageway 12C.
[0040] Then, the second guiding rod 28 swings downward to guide the
first sheet P1 to the third roller set 34, which feeds the first
sheet P1 from the second sub-passageway 12C to the second temporary
storage region 24.
[0041] Referring next to FIG. 4, after the first sheet P1 has left
the second sub-passageway 12C, the third roller set 34 is reversed
and the second guiding rod 28 swings upward so that the third
roller set 34 may feed the first sheet P1 from the second temporary
storage region 24 to the third passageway 16. Then, when the
sheet-output roller set 39 feeds the first sheet P1 in the third
passageway 16 to the sheet output tray 50, the sheet-input roller
31 also feeds the second sheet P2 to the first passageway 12 for
scan, and the overall scanning time may be saved accordingly.
[0042] If the front sides of the sheets in the sheet input tray 10
face downward, the front sides of the sheets in the sheet output
tray 50 also face downward and the order of the sheets is kept
unchanged after the above-mentioned sheet-feeding processes are
performed
[0043] On the other hand, when the simplex image processing such as
simplex scanning is to be performed, the sheet may be fed to the
second temporary storage region 24 and separated from the third
roller set 34 and then falls down to the sheet output tray 50.
[0044] FIG. 5 shows an automatic sheet feeder according to a second
embodiment of the invention. The second embodiment is similar to
the first embodiment except that the automatic sheet feeder of the
second embodiment is combined with a flatbed scanner 70 but the
automatic sheet feeder of the first embodiment is applied to the
sheet-fed scanner.
[0045] FIGS. 6 to 9 show several states of an automatic sheet
feeder according to a third embodiment of the invention,
respectively. As shown in FIGS. 6 to 9, the automatic sheet feeder
of the third embodiment of the invention is similar to that of the
first embodiment. The automatic sheet feeder of the first
embodiment, which is a straight forward type automatic sheet
feeder, is applied to the sheet-fed scanner and the sheet is fed in
an L-shaped path. However, the automatic sheet feeder of the third
embodiment, which is a U-shaped type automatic sheet feeder, is
used in combination with a flatbed scanner (similar to FIG. 5 but
not shown) having a movable scanning module 60, the sheet is fed in
a U-shaped path, and an auxiliary roller set 38 and a first roller
set 32 that may be omitted is newly added. The second roller set 33
and the auxiliary roller set 38 may be designed to share one roller
and the image processing region 20 is located between two first
roller sets 32. Since the operations of this embodiment is the same
as those of the first embodiment, detailed description thereof will
be omitted but only illustrated in the drawings.
[0046] On the other hand, when the simplex image processing such as
simplex scanning is to be performed, the height of the temporary
tray 21 may be lowered from the Q1 point down to the Q2 point.
Then, the sheet is fed to the first temporary storage region 22 and
separated from the second roller set 33 and then falls down to the
sheet output tray 50. It is to be noted that when the height of the
temporary tray 21 is lowered from the Q1 point to the Q2 point, the
duplex scanning processes will not be influenced because the sheet
is not released by the second roller set 33.
[0047] FIGS. 10 to 13 show several states of an automatic sheet
feeder according to a fourth embodiment of the invention,
respectively. As shown in FIG. 10, the automatic sheet feeder is
similar to that of FIG. 5 and is used in combination with a flatbed
scanner. For the sake of simplicity, only the scanning module 60 is
depicted. However, in other embodiments, the automatic sheet feeder
also may be applied to a printer. The automatic sheet feeder
includes a sheet input tray 10, a first passageway 12, a second
passageway 14, a third passageway 16, a sheet-feeding mechanism 30,
and a sheet output tray 50.
[0048] The sheet input tray 10 is used to store a plurality of
sheets including a first sheet P1 and a second sheet P2. Each of
the sheets has a front side and a back side. For example, the first
sheet P1 has a front side P1A and a back side P1B.
[0049] The sheets may be successively fed through the first
passageway 12, second passageway 14 and third passageway 16. The
first passageway 12 communicates with the sheet input tray 10. A
first end 14A of the second passageway 14 selectively communicates
with the first passageway 12, a second end 14B of the second
passageway 14 communicates with the first passageway 12. The third
passageway 16 selectively communicates with the first passageway
12.
[0050] The sheet-feeding mechanism 30 feeds the first sheet P1
successively from the sheet input tray 10 to the first passageway
12, the second passageway 14, the first passageway 12, and the
third passageway 16.
[0051] The sheet output tray 50, in which the sheets may be stored
after the scanning processes, communicates with the third
passageway 16. In order to increase the sheet-feeding speed, the
automatic sheet feeder of the invention is designed such that the
front side P1A of the first sheet P1 is toward opposite directions
when it passes through the first passageway 12 at the first and
second times. When the first sheet P1 is fed to the third
passageway 16, the second sheet P2 is fed to the first passageway
12.
[0052] The automatic sheet feeder in the embodiment further
includes a first temporary storage region 22, a first guiding rod
26, and a second guiding rod 28. The first temporary storage region
22, in which the first sheet P1 from the first passageway 12 is
temporarily stored, selectively communicates with the first
passageway 12 and the second passageway 14. The first guiding rod
26 switchably guides the first sheet P1 from the first passageway
12 to the first temporary storage region 22, and guides the first
sheet P1 from the first temporary storage region 22 to the second
passageway 14. The second guiding rod 28 switchably guides the
first sheet P1 from the first passageway 12 to the first temporary
storage region 22 or third passageway 16. In addition, an image
processing region 20 as described above is formed on the first
passageway 12.
[0053] In the embodiment, the sheet-feeding mechanism 30 includes a
sheet-input roller 31, a first roller set 32, a second roller set
33, a third roller set 34, a fourth roller set 35, a fifth roller
set 36 and a sheet-output roller set 39.
[0054] First, the sheet-input roller 31 feeds the first sheet P1
from the sheet input tray 10 to the first passageway 12. The front
side P1A of the first sheet P1 in the image processing region 20
faces downward and is scanned by the scanning module 60. The first
roller set 32 and the second roller set 33 are located on the first
passageway 12 to assist in feeding the first sheet P1 from the
sheet input tray to the first temporary storage region 22. At this
time, the first guiding rod 26 swings upward and the second guiding
rod 28 swings downward to guide the first sheet P1 to the third
roller set 34. Next, the third roller set 34 feeds the first sheet
P1 from the first passageway 12 to the first temporary storage
region 22.
[0055] Referring next to FIG. 11, after the first sheet P1 has left
the first passageway 12, the third roller set 34 is reversed, and
the first guiding rod 26 swings downward so that the third roller
set 34 may feed the first sheet P1 from the first temporary storage
region 22 to the second passageway 14. Then, the first sheet P1
enters the first passageway 12 from the second end 14B the second
passageway 14, and the back side P1B of the first sheet P1 in the
image processing region 20 faces downward (the front side P1A faces
upward) and is scanned by the scanning module 60.
[0056] Next, referring to FIG. 12, the second guiding rod 28 swings
upward to guide the first sheet P1 to the third passageway 16. It
is to be noted that the third roller set 34 and the fourth roller
set 35 share one roller.
[0057] Then, as shown in FIG. 13, when the first sheet P1 is still
fed in the third passageway 16, the second sheet P2 has been fed to
the first passageway 12 for scan, and the overall scanning time may
be saved accordingly.
[0058] If the front sides of the sheets in the sheet input tray 10
face downward, the front sides of the sheets in the sheet output
tray 50 also face downward and the order of the sheets is kept
unchanged after the above-mentioned sheet-feeding processes are
performed.
[0059] On the other hand, when the simplex image processing such as
simplex scanning is to be performed, the height of the temporary
tray 21 may be lowered from the Q1 point down to the Q2 point.
Then, the sheet is fed to the first temporary storage region 22 and
separated from the third roller set 34 and then falls down to the
sheet output tray 50. It is to be noted that when the height of the
temporary tray 21 is lowered from the Q1 point to the Q2 point, the
duplex scanning processes will not be influenced because the sheet
is not released by the third roller set 34. Consequently, the
sheet-feeding mechanisms 30 in FIGS. 1 to 13 may selectively
perform a duplex sheet-feeding mode and a simplex sheet-feeding
mode. In the duplex sheet-feeding mode, the sheet-feeding mechanism
30 feeds the first sheet P1 or the second sheet P2 from the sheet
input tray 10 successively through the first passageway 12, the
second passageway 14, the first passageway 12 and third passageway
16, and finally to the sheet output tray 50. In the simplex
sheet-feeding mode, the sheet-feeding mechanism 30 feeds the first
sheet P1 or the second sheet P2 from the sheet input tray 10
through the first passageway 12 and finally to the sheet output
tray 50. After the simplex sheet-feeding mode or duplex
sheet-feeding mode, the relatively order between the first sheet
and the second sheet is kept unchanged.
[0060] Consequently, the invention sufficiently utilizes the time
when the first sheet is fed through the third passageway to feed
and scan the second sheet, so the overall scanning time may be
effectively shortened and the duplex scanning operation may be
accelerated without influencing the scanning effects.
Alternatively, when the automatic sheet feeder is applied to a
printer, the overall printing time also may be effectively
shortened.
[0061] According to the above-mentioned embodiments, the automatic
sheet feeder of the invention may satisfy the facilitated functions
of duplex and simplex image processing, effectively accelerate the
duplex image processing, and greatly shorten the image processing
time.
[0062] FIGS. 14 and 15 show the first and second states of the
automatic sheet feeder according to a fifth embodiment of the
invention. Referring to FIGS. 14 and 15, the fifth embodiment of
the invention provides an automatic sheet feeder including a sheet
input tray 10, a sheet output tray 50, a first passageway 12, a
second passageway 14, and a sheet-feeding mechanism 30.
[0063] The sheet input tray 10 is used to store a plurality of
sheets including a first sheet P1 and a second sheet P2. Each of
the sheets has a front side (e.g., P1A) and a back side (e.g.,
P1B). The sheet output tray 50 may store the sheets after being
fed. The sheets may be successively fed through the first
passageway 12 and the second passageway 14. The first passageway 12
communicates with the sheet input tray 10, a first end 14A of the
second passageway 14 selectively communicates with the first
passageway 12, a second end 14B of the second passageway 14
communicates with the first passageway 12. The sheet-feeding
mechanism 30 feeds the first sheet P1 from the sheet input tray 10
successively through the first passageway 12, the second passageway
14 and the first passageway 12, and finally to the sheet output
tray 50.
[0064] The first passageway 12 includes a main passageway 12A
communicating with the sheet input tray 10, a first sub-passageway
12B communicating with the main passageway 12A and the second
passageway 14, a second sub-passageway 12C communicating with the
main passageway 12A and the sheet output tray 50, and a
main/sub-passageway guiding rod 12D for switchably guiding the
first sheet P1 from the main passageway 12A to the first
sub-passageway 12B or the second sub-passageway 12C.
[0065] A temporary storage region 22 selectively communicates with
the first sub-passageway 12B and the second passageway 14 to
temporarily store the first sheet P1 coming from the first
sub-passageway 12B. A first guiding rod 26 switchably guides the
first sheet P1 from the first sub-passageway 12B to the temporary
storage region 22, and the first sheet P1 from the temporary
storage region 22 to the second passageway 14.
[0066] The main passageway 12A may be formed with an image
processing region 20. A scanning module 60 or a printing module
(not shown) may be provided in correspondence with the image
processing region 20 to process (e.g., scan or print) the sheet
passing through the image processing region 20.
[0067] The sheet-feeding mechanism 30 includes a sheet-input roller
31, a first roller set 32, a second roller set 33 and a
sheet-output roller set 39. The sheet-input roller 31 feeds the
first sheet P1 from the sheet input tray 10 to the main passageway
12A. The first roller set 32 is located on the main passageway 12A
to assist in feeding the first sheet P1 from the sheet input tray
10 to the first sub-passageway 12B, and the first sheet P1 from the
second passageway 14 to the second sub-passageway 12C. The second
roller set 33 feeds the first sheet P1 from the first
sub-passageway 12B to the temporary storage region 22 and the first
sheet P1 from the temporary storage region 22 to the second
passageway 14. The sheet-output roller set 39 feeds the first sheet
P1 from the second sub-passageway 12C to the sheet output tray
50.
[0068] In this embodiment, when the duplex scanning is performed,
the sheet only has to be turned over twice but not thrice. Thus,
time may be saved.
[0069] FIGS. 16 and 17 show two states of an automatic sheet feeder
according to a sixth embodiment of the invention. Referring to
FIGS. 16 and 17, the sixth embodiment of the invention provides an
automatic sheet feeder including a sheet input tray 10, a sheet
output tray 50, a first passageway 12, a second passageway 14 and a
sheet-feeding mechanism 30.
[0070] The sheet input tray 10 is used to store a plurality of
sheets including a first sheet P1 and a second sheet P2. Each of
the sheets has a front side (e.g., P1A) and a back side (e.g.,
P1B). The sheet output tray 50 may store the sheets after being
fed. The sheets may be successively fed through the first
passageway 12 and the second passageway 14. The first passageway 12
communicates with the sheet input tray 10, a first end 14A of the
second passageway 14 selectively communicates with the first
passageway 12, a second end 14B of the second passageway 14
communicates with the first passageway 12. The sheet-feeding
mechanism 30 feeds the first sheet P1 from the sheet input tray 10
successively through the first passageway 12, the second passageway
14 and the first passageway 12, and finally to the sheet output
tray 50.
[0071] A temporary storage region 22 selectively communicates with
the first passageway 12 and the second passageway 14 to temporarily
store the first sheet P1 from the first passageway 12. A first
guiding rod 26 switchably guides the first sheet P1 from the first
passageway 12 to the temporary storage region 22, and the first
sheet P1 from the temporary storage region 22 to the second
passageway 14. A second guiding rod 28 switchably guides the first
sheet P1 from the first passageway 12 to the temporary storage
region 22 or the sheet output tray 50.
[0072] The first passageway 12 may be formed with an image
processing region 20. A scanning module 60 or a printing module
(not shown) may be provided in correspondence with the image
processing region 20 to process (e.g., scan or print) the sheet
passing through the image processing region 20.
[0073] The sheet-feeding mechanism 30 includes a sheet-input roller
31, a first roller set 32, a second roller set 33, and a
sheet-output roller set 39. The sheet-input roller 31 feeds the
first sheet P1 from the sheet input tray 10 to the first passageway
12. The first roller set 32 and the second roller set 33 are
located on the first passageway 12 to assist in feeding the first
sheet P1 from the sheet input tray 10 to the temporary storage
region 22, and the first sheet P1 from the second passageway 14 to
the sheet output tray 50. The sheet-output roller set 39 feeds the
first sheet P1 from the first passageway 12 to the sheet output
tray 50. In this embodiment, the second roller set 33 and the
sheet-output roller set 39 share the same roller.
[0074] FIG. 18 shows an automatic sheet feeder according to a
seventh embodiment of the invention. The embodiment is similar to
the sixth embodiment except that the second guiding rod 28 and the
second roller set 33 of FIG. 16 are omitted and a sheet-output
roller set 39 is used instead of the second roller set 33.
Consequently, the sheet-feeding mechanism 30 includes a sheet-input
roller 31, a first roller set 32 and a sheet-output roller set 39.
The sheet-input roller 31 feeds the first sheet P1 from the sheet
input tray 10 to the first passageway 12. The first roller set 32
is located on the first passageway 12 to assist in feeding the
first sheet P1 from the sheet input tray 10 to the temporary
storage region 22, and the first sheet P1 from the second
passageway 14 to the temporary storage region 22. The sheet-output
roller set 39 feeds the first sheet P1 from the first passageway 12
to the temporary storage region 22, and then feeds the first sheet
P1, which is temporarily stored in the temporary storage region 22,
to the second passageway 14. The sheet-output roller set 39 further
feeds the first sheet P1 from the second passageway 14 and the
first passageway 12 to the temporary storage region 22 and then
release the first sheet P1 to let it fall down to the sheet output
tray 50.
[0075] Compared to the sixth embodiment, the automatic sheet feeder
of the seventh embodiment has a simpler structure.
[0076] According to the above-mentioned embodiments, the automatic
sheet feeder of the invention may effectively accelerate the duplex
image processing and greatly shorten the image processing time.
[0077] While the invention has been described by way of examples
and in terms of preferred embodiments, it is to be understood that
the invention is not limited to the disclosed embodiments. To the
contrary, it is intended to cover various modifications. Therefore,
the scope of the appended claims should be accorded the broadest
interpretation so as to encompass all such modifications.
* * * * *