U.S. patent application number 11/470448 was filed with the patent office on 2008-03-06 for document feeder.
This patent application is currently assigned to PRIMAX ELECTRONICS LTD.. Invention is credited to Hsin-Wen Lee.
Application Number | 20080054549 11/470448 |
Document ID | / |
Family ID | 39115543 |
Filed Date | 2008-03-06 |
United States Patent
Application |
20080054549 |
Kind Code |
A1 |
Lee; Hsin-Wen |
March 6, 2008 |
DOCUMENT FEEDER
Abstract
A document feeder includes a housing, a sheet pick-up arm and a
stopper. The housing includes a sheet feeding path for placing
paper sheets thereon. The sheet pick-up arm is movable between a
first position and a second position. The sheet pick-up arm has a
protrusion structure. The stopper is disposed under the sheet
feeding path and includes a pivotal portion and a sheet stop
portion. The sheet stop portion has a hooking part corresponding to
the protrusion structure. When the sheet pick-up arm is moved to
the first position, the protrusion structure is located in the
swing track of the hooking part to restrain the swing range of the
sheet stop portion. When the sheet pick-up arm is moved to the
second position, the protrusion structure is deviated from the
swing track of the hooking part to permit free swing of the sheet
stop portion.
Inventors: |
Lee; Hsin-Wen; (Taipei,
TW) |
Correspondence
Address: |
KIRTON AND MCCONKIE
60 EAST SOUTH TEMPLE,, SUITE 1800
SALT LAKE CITY
UT
84111
US
|
Assignee: |
PRIMAX ELECTRONICS LTD.
Taipei
TW
|
Family ID: |
39115543 |
Appl. No.: |
11/470448 |
Filed: |
September 6, 2006 |
Current U.S.
Class: |
271/117 |
Current CPC
Class: |
B65H 3/565 20130101;
B65H 3/0615 20130101 |
Class at
Publication: |
271/117 |
International
Class: |
B65H 3/06 20060101
B65H003/06 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 17, 2006 |
TW |
095125986 |
Claims
1. A document feeder comprising: a housing including a sheet
feeding path for placing paper sheets thereon; a sheet pick-up arm
pivotally mounted above said sheet feeding path and movable between
a first position and a second position, wherein said sheet pick-up
arm has a protrusion structure; and a stopper disposed under said
sheet feeding path and comprising a pivotal portion and a sheet
stop portion, said sheet stop portion having a hooking part
corresponding to said protrusion structure, wherein said protrusion
structure is located in the swing track of said hooking part to
restrain the swing range of said sheet stop portion when said sheet
pick-up arm is moved to said first position, and said protrusion
structure is deviated from the swing track of said hooking part to
permit free swing of said sheet stop portion when said sheet
pick-up arm is moved to said second position.
2. The document feeder according to claim 1 where said sheet
pick-up arm comprises a sheet pick-up roller and a sheet separation
roller.
3. The document feeder according to claim 1 further comprising a
driving shaft for driving said sheet pick-up arm, wherein said
sheet separation roller is sheathed around the driving shaft.
4. The document feeder according to claim 1 wherein said stopper
further comprises a loading portion, said loading portion and said
sheet stop portion being arranged on opposite sides of said pivotal
portion, wherein the torque applied on said loading portion is
greater than the torque applied on said sheet stop portion with
said pivotal portion serving as a fulcrum.
5. The document feeder according to claim 1 further comprising a
torsion spring having an end sustained against said sheet stop
portion.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a document feeder, and more
particularly to a document feeder having a stopper.
BACKGROUND OF THE INVENTION
[0002] Conventionally, for scanning several paper sheets, the paper
sheets should be manually placed on the scanning platform of the
image scanners one by one. This means of manually feeding the paper
sheets is time-consuming and laboring. Nowadays, the image scanner
usually has a document feeder for successively and continuously
feeding many paper sheets. As known, a conventional document feeder
has a sheet pick-up module arranged in the sheet feeding path for
automatically feeding the paper sheets one by one at a time.
[0003] For assuring that a stack of paper sheets are precisely
positioned within the sheet feeding path, the document feeder
further has a stopper under the sheet pick-up module. When the
stack of paper sheets enters the sheet feeding path, the stopper is
sustained against the front edges of the stack such that the paper
sheets are positioned under the sheet pick-up module. Once the
paper sheets are stopped by the stopper, the user may feel that the
paper sheets are placed in position. When the sheet pick-up module
performs the sheet pick-up operation, the stopper is shifted such
that the paper sheets are smoothly transported through the sheet
feeding path.
[0004] Please refer to FIG. 1, which is a schematic perspective
view illustrating relative locations of the sheet pick-up module
and the stopper of a conventional document feeder. The stopper 12
is pivotal and disposed under the sheet pick-up module 11. The
sheet pick-up module 11 comprises a sustaining portion 111.
Correspondingly, the stopper 12 comprises a tilt portion 121 and a
sheet stop portion 122. When the sheet pick-up module 11 is lifted
to a standby position, the sheet stop portion 122 is rotated to an
upright position so as to be sustained against the front edges of
the stack of paper sheets. Whereas, during the sheet pick-up module
11 is lowered to a sheet pick-up position, the sustaining portion
111 is also lowered down to touch the tilt portion 121 of the
stopper 12. In response to the external force generated from
rotation of the sheet pick-up module 11, the sheet stop portion 122
is rotated under the sheet feeding path. Under this circumstance,
the paper sheets can be smoothly transported through the sheet
feeding path without being stopped by the stopper 12.
[0005] However, the stopper 12 of the conventional document feeder
still has some drawbacks. For example, when the sheet pick-up
module 11 is in the standby position, the sheet stop portion 122 of
the stopper 12 is only sustained against the lower portions of the
paper sheets, but the upper portion of the paper sheets may
suppress the tilt portion 121 of the stopper 12. As a result, the
sheet stop portion 122 is rotated under the sheet feeding path
before the sheet pick-up operation is done, so that the function of
the stopping the paper sheets is lost.
[0006] In views of the above-described disadvantages resulted from
the prior art, the applicant keeps on carving unflaggingly to
develop an improved document feeder according to the present
invention through wholehearted experience and research.
SUMMARY OF THE INVENTION
[0007] It is an object of the present invention to provide a
document feeder for properly stopping or allowing the paper sheets
to be transported through the sheet feeding path with the
cooperation of the sheet pick-up arm and the stopper.
[0008] In accordance with an aspect of the present invention, there
is provided a document feeder. The document feeder includes a
housing, a sheet pick-up arm and a stopper. The housing includes a
sheet feeding path for placing paper sheets thereon. The sheet
pick-up arm is pivotally mounted above the sheet feeding path and
movable between a first position and a second position. The sheet
pick-up arm has a protrusion structure. The stopper is disposed
under the sheet feeding path and includes a pivotal portion and a
sheet stop portion. The sheet stop portion has a hooking part
corresponding to the protrusion structure. When the sheet pick-up
arm is moved to the first position, the protrusion structure is
located in the swing track of the hooking part to restrain the
swing range of the sheet stop portion. When the sheet pick-up arm
is moved to the second position, the protrusion structure is
deviated from the swing track of the hooking part to permit free
swing of the sheet stop portion.
[0009] In an embodiment, the sheet pick-up arm comprises a sheet
pick-up roller and a sheet separation roller.
[0010] In an embodiment, the document feeder further comprises a
driving shaft for driving the sheet pick-up arm, wherein the sheet
separation roller is sheathed around the driving shaft.
[0011] In an embodiment, the stopper further comprises a loading
portion. The loading portion and the sheet stop portion are
arranged on opposite sides of the pivotal portion. With the pivotal
portion serving as a fulcrum, the torque applied on the loading
portion is greater than the torque applied on the sheet stop
portion.
[0012] In an embodiment, the document feeder further comprises a
torsion spring having an end sustained against the sheet stop
portion.
[0013] The above objects and advantages of the present invention
will become more readily apparent to those ordinarily skilled in
the art after reviewing the following detailed description and
accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a schematic perspective view illustrating relative
locations of the sheet pick-up module and the stopper of a
conventional document feeder;
[0015] FIG. 2 is a schematic perspective view of a document feeder
according to a preferred embodiment of the present invention;
[0016] FIG. 3A is a schematic perspective view illustrating
relative locations of the sheet pick-up module and the stopper when
the sheet pick-up module is adjusted to a standby position;
[0017] FIG. 3B is a schematic perspective view illustrating
relative locations of the sheet pick-up module and the stopper when
the sheet pick-up module is adjusted to a sheet feeding
position;
[0018] FIGS. 4A-4F are schematic cross-sectional views illustrating
the process of performing the sheet pick-up operation by the sheet
pick-up module and the stopper of the present document feeder.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0019] Referring to FIG. 2, a schematic perspective view of a
document feeder according to a preferred embodiment of the present
invention is illustrated. The document feeder 2 includes a housing
20, a sheet pick-up module 21 and a stopper 22. The housing 20 has
a sheet feeding path 201 for placing therein the paper sheets S to
be transported therethrough. The sheet pick-up module 21 is
pivotally mounted above the sheet feeding path 201 for feeding the
paper sheets S through the sheet feeding path 201. The sheet
pick-up module 21 includes a sheet pick-up arm 211 and a driving
shaft 212. The sheet pick-up arm 211 includes a sheet pick-up
roller 211A and a sheet separation roller 211B (as is shown in FIG.
3A). The sheet separation roller 211B is also sheathed around the
driving shaft 212. After the sheet pick-up operation has been done,
the sheet pick-up arm 211 is lifted to a standby position upon
rotation of the driving shaft 212. For a purpose of feeding the
paper sheets, the driving shaft 212 is driven to rotate in the
opposite direction such that the sheet pick-up arm 211 is lowered
to the sheet feeding position. Meanwhile, a sheet pick-up roller
221A of the sheet pick-up arm 212 transports the paper sheets S
forwardly and the sheet separation roller 211B of the sheet pick-up
arm 212 is rotated to separate the top paper sheets from the stack
of paper sheets, thereby picking a single paper sheets.
[0020] Please refer to FIG. 2 again. The document feeder 2 further
includes a stopper 22 accommodated within a recess 202 under the
sheet feeding path 201, as is also shown in FIG. 4A. When the sheet
pick-up arm 211 of the sheet pick-up module 21 is lifted to the
standby position, the stopper 22 is rotated to an upright position
so as to be sustained against the front edges of the stack of paper
sheets. As a result, the stack of paper sheets S fails to be
transported through the sheet feeding path 201. Whereas, during the
sheet pick-up module 21 is lowered to a sheet pick-up position, a
free swing of the stopper 22 is rendered. Under this circumstance,
the stack of paper sheets S may suppress the stopper 22 and is then
transported through the sheet feeding path 201.
[0021] Please refer to FIGS. 3A and 3B, which are schematic
perspective views illustrating relative locations of the sheet
pick-up module 21 and the stopper 22 when the sheet pick-up module
21 is adjusted to a standby position and a sheet feeding position,
respectively. As can be seen in FIGS. 3A and 3B, the stopper 22 is
made upright when the sheet pick-up arm 211 of the sheet pick-up
module 21 is lifted to the standby position, and a free swing of
the stopper 22 is rendered when the sheet pick-up arm 211 of the
sheet pick-up module 21 is lowered to the sheet feeding
position.
[0022] The stopper 22 includes a pivotal portion 221, a loading
portion 222 and a sheet stop portion 223. The pivotal portion 221
is accommodated within a recess 202 (as is also shown in FIG. 4A).
The pivotal portion 221 is substantially a cylindrical post serving
as a rotating shaft of the stopper 22. That is, by using the
pivotal portion 221 as the fulcrum, the loading portion 222 and the
sheet stop portion 223 are rotatable. The sheet stop portion 223 is
substantially a stop plate to be sustained against the front edges
of the stack of paper sheets S. The loading portion 222 and the
sheet stop portion 223 are arranged on opposite sides of the
pivotal portion 221. With the pivotal portion 221 serving as the
fulcrum, the torque applied on the loading portion 222 is greater
than the torque applied on the sheet stop portion 223. As a
consequence, once the sheet stop portion 223 is not suppressed by
the paper sheets S, the sheet stop portion 223 will be returned
toward the upright position due to the torque applied on the
loading portion 222.
[0023] In addition, the sheet stop portion 223 has a hooking part
223A extending from a first lateral side thereof. Corresponding to
the hooking part 223A, the sheet pick-up arm 211 has a protrusion
structure 211C extending from a second lateral side thereof. When
the sheet pick-up arm 211 is lifted to the standby position as
shown in FIG. 3A, the hooking part 223A of the sheet stop portion
23 is located in the swing track 223A' of the hooking part 223A,
thereby restraining the swing range of the sheet stop portion 223.
That is, when the sheet pick-up arm 211 is lifted to the standby
position, the hooking part 223A of the sheet stop portion 23 is
hooked onto the protrusion structure 211C of the sheet pick-up arm
211 such that the sheet stop portion 223 maintains upright to stop
the paper sheets. When the sheet pick-up arm 211 is lowered to the
sheet feeding position as shown in FIG. 3B, the hooking part 223A
of the sheet stop portion 23 is deviated from the swing track 223A'
of the hooking part 223A to permit free swing of the sheet stop
portion 23.
[0024] In this embodiment of the document feeder 2, the hooking
part 223A is extended from the first lateral side of the sheet stop
portion 223, and the protrusion structure 21 IC is extended from
the second lateral side of the sheet pick-up arm 211. When the
hooking part 223A is located in the swing track 223A' of the
hooking part 223A, the sheet stop portion 223 will maintains at its
upright position to stop the paper sheets. Whereas, the hooking
part 223A is deviated from the swing track 223A' of the hooking
part 223A, a free swing of the sheet stop portion 23 is permitted
such that the paper sheets S is transported through the sheet
feeding path 201.
[0025] As previously described, in the conventional document
feeder, the upper portions of the paper sheets may suppress the
tilt portion of the stopper when the sheet pick-up module is in the
standby position. That is, the function of the stopping the paper
sheets is readily lost by using the conventional document feeder.
By the present document feeder 2, with the cooperation of the
hooking part 223A of the sheet stop portion 23 and the protrusion
structure 211C of the sheet pick-up arm 211, the function of
stopping the paper sheets is selectively enabled or disabled when
the sheet pick-up arm 211 is lifted to the standby position or
lower to the sheet feeding position. As a consequence, the upper
portions of the paper sheets are still stopped when the paper
sheets S are placed on the sheet feeding path.
[0026] Hereinafter, a process of performing the sheet pick-up
operation by the sheet pick-up module 21 and the stopper 22 of the
document feeder 2 will be illustrated with reference to FIGS.
4A-4F.
[0027] First of all, as shown in FIG. 4A, when the sheet pick-up
arm 211 is lifted to the standby position, the hooking part 223A of
the sheet stop portion 23 is hooked onto the protrusion structure
21 IC of the sheet pick-up arm 211. Under this circumstance, the
sheet stop portion 223 of the stopper 22 is made upright and thus
the paper sheets S are hindered from being transported through the
sheet feeding path 201. Moreover, since the hooking part 223A is
hooked onto the protrusion structure 21 IC, the stopper 22 will not
be suppressed by the sheet pick-up arm 211 to rotate.
[0028] Next, as shown in FIG. 4B, the sheet pick-up arm 211 is
lowered to the sheet feeding position, and the sheet pick-up roller
21 1A is rotated on the top paper sheets. As the sheet pick-up arm
211 is lowered to the sheet feeding position, the protrusion
structure 211C is detached from the hooking part 223A and thus a
free swing of the sheet stop portion 223 of the stopper 22 is
rendered.
[0029] Next, as shown in FIG. 4C, upon rotation of the sheet
pick-up roller 21 1A, the top paper sheets S is transported to
enter the sheet feeding path 201. During the process of
transporting the top paper sheets S into the sheet feeding path
201, the sheet stop portion 223 of the stopper 22 is swung toward
the sheet feeding path 201 by the paper sheets S.
[0030] In FIG. 4D, as the sheet pick-up roller 21 1A of the sheet
pick-up arm 211 is continuously rotated, the sheet stop portion 223
of the stopper 22 is suppressed by the paper sheets S to be fully
accommodated within the recess 202.
[0031] In FIG. 4E, after the paper sheets S is transported across
the sheet stop portion 223, the sheet stop portion 223 of the
stopper 22 is no loner suppressed by the paper sheets S. Meanwhile,
the sheet stop portion 223 will be returned toward the upright
position due to the torque applied on the loading portion 222.
[0032] After the sheet feeding operation is finished, the sheet
pick-up arm 211 is lifted to the standby position. Meanwhile, the
protrusion structure 21 IC is located in the swing track 223A' of
the hooking part 223A, thereby restraining the swing range of the
sheet stop portion 223.
[0033] Please refer to FIG. 3A, 4D and 4E. The sheet pick-up arm
211 of the document feeder 2 further comprises a stopping piece
211D corresponding to the sheet stop portion 223. After the paper
sheets S is transported across the sheet stop portion 223 and the
sheet stop portion 223 is swung backwardly, the end of the sheet
stop portion 223 is stopped by the stopping piece 211D such that
the sheet stop portion 223 is in the upright position.
[0034] As previously described, the sheet stop portion 223 will be
kept at the upright position due to the torque applied on the
loading portion 222. Alternatively, the document feeder 2 further
includes a torsion spring 224 having an end sustained against the
sheet stop portion 223. Once the paper sheets S suppresses the
sheet stop portion 223 to permit rotation of the sheet stop portion
223, a torsion force is resulted from the torsion spring 224. After
the paper sheets S is transported across the sheet stop portion 223
and the sheet stop portion 223 is no longer suppressed by the sheet
stop portion 223, the torsion force of the torsion spring 224 will
facilitate the reverse rotation of the sheet stop portion 223 to
the upright position.
[0035] While the invention has been described in terms of what is
presently considered to be the most practical and preferred
embodiments, it is to be understood that the invention needs not be
limited to the disclosed embodiment. On the contrary, it is
intended to cover various modifications and similar arrangements
included within the spirit and scope of the appended claims which
are to be accorded with the broadest interpretation so as to
encompass all such modifications and similar structures.
* * * * *