U.S. patent application number 14/560430 was filed with the patent office on 2016-06-09 for sheet height sensor using movable and stationary mirrors.
The applicant listed for this patent is Xerox Corporation. Invention is credited to Timothy J. Clark, David M. Gurak, Bruce H. Smith.
Application Number | 20160159117 14/560430 |
Document ID | / |
Family ID | 55920059 |
Filed Date | 2016-06-09 |
United States Patent
Application |
20160159117 |
Kind Code |
A1 |
Gurak; David M. ; et
al. |
June 9, 2016 |
SHEET HEIGHT SENSOR USING MOVABLE AND STATIONARY MIRRORS
Abstract
Apparatuses include a conveyor moving in a processing direction,
a print head positioned adjacent the conveyor, a light source
positioned adjacent a first side of the conveyor, a movable mirror
positioned adjacent a second side of the conveyor, that is across
the conveyor from the first side of the conveyor, a fixed mirror
positioned adjacent the first side of the conveyor (the fixed
mirror is between the light source and the print head), and a light
sensor position adjacent the second side of the conveyor. The light
sensor is between the movable mirror and the print head. The light
source outputs light to the movable mirror across the conveyor, the
movable mirror directs the light back across the conveyor to the
fixed mirror, and the fixed mirror directs the light again across
the conveyor to the light sensor.
Inventors: |
Gurak; David M.; (Webster,
NY) ; Clark; Timothy J.; (Weedsport, NY) ;
Smith; Bruce H.; (Webster, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Xerox Corporation |
Norwalk |
CT |
US |
|
|
Family ID: |
55920059 |
Appl. No.: |
14/560430 |
Filed: |
December 4, 2014 |
Current U.S.
Class: |
347/16 |
Current CPC
Class: |
G01B 11/02 20130101;
B41J 13/0063 20130101; G01B 11/06 20130101; G01B 11/0608 20130101;
G01B 11/00 20130101; B41J 11/0035 20130101; B41J 11/007 20130101;
B41J 11/003 20130101; B41J 13/0009 20130101; B41J 11/0085 20130101;
G01B 11/0691 20130101 |
International
Class: |
B41J 13/00 20060101
B41J013/00; B41J 11/00 20060101 B41J011/00; G01B 11/06 20060101
G01B011/06 |
Claims
1. A printing apparatus comprising: a conveyor moving in a
processing direction; a print head positioned adjacent said
conveyor; a light source positioned adjacent a first side of said
conveyor, said first side of said conveyor being parallel to said
processing direction; a movable mirror positioned adjacent a second
side of said conveyor, said second side of said conveyor being
parallel to said processing direction, said second side of said
conveyor being across said conveyor from said first side of said
conveyor in a second direction, said second direction being
approximately perpendicular to said processing direction; a fixed
mirror positioned adjacent said first side of said conveyor, said
fixed mirror being positioned along said first side of said
conveyor between said light source and said print head; and a light
sensor positioned adjacent said second side of said conveyor, said
light sensor being positioned along said second side of said
conveyor between said movable mirror and said print head, said
light source outputting light to said movable mirror, said movable
mirror directing said light to said fixed mirror, and said fixed
mirror directing said light to said light sensor.
2. The printing apparatus according to claim 1, said light source,
said movable mirror, and said fixed mirror being positioned
relative to each other to direct said light from said light source,
reflected by said movable mirror and said fixed the mirror, to said
light sensor in a single plane.
3. The printing apparatus according to claim 2, said single plane
being parallel to a second plane formed by a surface of said
conveyor that is moving in said processing direction.
4. The printing apparatus according to claim 3, said single plane
comprising a height limit above said second plane in a third
direction that intersects said surface of said conveyor toward said
print head, said height limit being a limit for items being moved
by said conveyor past said print head.
5. The printing apparatus according to claim 2, said light source
producing a plurality of parallel light beams in different planes
parallel to said single plane.
6. The printing apparatus according to claim 1, further comprising
a plurality of additional fixed mirrors positioned on opposite
sides of said conveyor.
7. The printing apparatus according to claim 1, said processing
direction moving items on said conveyor past said light sensor
before moving said items past said print head.
8. A printing apparatus comprising: a perforated vacuum belt having
a surface moving in a processing direction; a print head positioned
adjacent said perforated vacuum belt; a light source positioned
adjacent a first side of said perforated vacuum belt, said first
side of said perforated vacuum belt being parallel to said
processing direction; a movable mirror positioned adjacent a second
side of said perforated vacuum belt, said movable mirror rotating
in a plane parallel to said surface of said perforated vacuum belt,
said second side of said perforated vacuum belt being parallel to
said processing direction, said second side of said perforated
vacuum belt being across said perforated vacuum belt from said
first side of said perforated vacuum belt in a second direction,
said second direction being approximately perpendicular to said
processing direction; a fixed mirror positioned adjacent said first
side of said perforated vacuum belt, said fixed mirror being
positioned along said first side of said perforated vacuum between
said light source and said print head; and a light sensor array
positioned adjacent said second side of said perforated vacuum
belt, said light sensor array being positioned along said second
side of said perforated vacuum between said movable mirror and said
print head, said light source outputting light to said movable
mirror, said movable mirror directing said light to said fixed
mirror, and said fixed mirror directing said light to said light
sensor array.
9. The printing apparatus according to claim 8, said light source,
said movable mirror, and said fixed mirror being positioned
relative to each other to direct said light from said light source,
reflected by said movable mirror and said fixed the mirror, to said
light sensor array in a single plane.
10. The printing apparatus according to claim 9, said single plane
being parallel to a second plane formed by said surface of said
perforated vacuum belt.
11. The printing apparatus according to claim 10, said single plane
comprising a height limit above said second plane in a third
direction that intersects said surface of said perforated vacuum
belt toward said print head, said height limit being a limit for
items being moved by said perforated vacuum belt past said print
head.
12. The printing apparatus according to claim 9, said light source
producing a plurality of parallel light beams in different planes
parallel to said single plane.
13. The printing apparatus according to claim 8, further comprising
a plurality of additional fixed mirrors positioned on opposite
sides of said perforated vacuum belt.
14. The printing apparatus according to claim 8, said processing
direction moving items on said perforated vacuum belt past said
light sensor before moving said items past said print head.
15. An inkjet printer comprising: a perforated vacuum belt having a
surface moving in a processing direction; an inkjet print head
positioned adjacent said perforated vacuum belt; a light source
positioned adjacent a first side of said perforated vacuum belt,
said first side of said perforated vacuum belt being parallel to
said processing direction; a movable mirror positioned adjacent a
second side of said perforated vacuum belt, said movable mirror
rotating in a plane parallel to said surface of said perforated
vacuum belt, said second side of said perforated vacuum belt being
parallel to said processing direction, said second side of said
perforated vacuum belt being across said perforated vacuum belt
from said first side of said perforated vacuum belt in a second
direction, said second direction being approximately perpendicular
to said processing direction; a fixed mirror positioned adjacent
said first side of said perforated vacuum belt, said fixed mirror
being positioned along said first side of said perforated vacuum
between said light source and said inkjet print head; and a light
sensor array positioned adjacent said second side of said
perforated vacuum belt, said light sensor array being positioned
along said second side of said perforated vacuum between said
movable mirror and said inkjet print head, said light source
outputting light to said movable mirror, said movable mirror
directing said light to said fixed mirror, and said fixed mirror
directing said light to said light sensor array.
16. The inkjet printer according to claim 15, said light source,
said movable mirror, and said fixed mirror being positioned
relative to each other to direct said light from said light source,
reflected by said movable mirror and said fixed the mirror, to said
light sensor array in a single plane.
17. The inkjet printer according to claim 16, said single plane
being parallel to a second plane formed by said surface of said
perforated vacuum belt.
18. The inkjet printer according to claim 17, said single plane
comprising a height limit above said second plane in a third
direction that intersects said surface of said perforated vacuum
belt and said second plane, said height limit being a limit for
sheets of print media being moved by said perforated vacuum belt
past said inkjet print head.
19. The inkjet printer according to claim 16, said light source
producing a plurality of parallel light beams in different planes
parallel to said single plane.
20. The inkjet printer according to claim 15, further comprising a
plurality of additional fixed mirrors positioned on opposite sides
of said perforated vacuum belt.
Description
BACKGROUND
[0001] Systems and devices herein generally relate to devices that
determine the height of items (e.g., sheets of print media) above a
conveyor within a printing device, and more particularly to a
system that utilizes movable and stationary mirrors in a compact
and inexpensive design.
[0002] As the quality and speed of printing devices improves, the
tolerances within such printing devices decreases. These tighter
tolerances can cause problems if the print media being utilized has
an inconsistent thickness. Specifically, if a sheet of print media
is thicker than the tolerances within the printing device, the
print media can jam within the printing device and/or damage the
internals of the printing device. Therefore, systems that can
determine the height of the print media accurately and
inexpensively are highly valued.
SUMMARY
[0003] An exemplary apparatus herein includes a conveyor moving in
a processing direction, a print head positioned adjacent the
conveyor, and a light source positioned adjacent a first side of
the conveyor. The first side of the conveyor is parallel to the
processing direction. This exemplary apparatus also includes a
movable mirror positioned across the conveyor, adjacent a second
side of the conveyor. The second side of the conveyor is parallel
to the processing direction, and is across the conveyor from the
first side of the conveyor in a second direction that is
approximately perpendicular to the processing direction.
[0004] This apparatus also has a fixed mirror positioned adjacent
the first side of the conveyor. The fixed mirror is between the
light source and the print head. Further, a light sensor is
positioned adjacent the second side of the conveyor. The light
sensor is between the movable mirror and the print head. The
"processing direction" is a direction that moves items on the
conveyor past the light sensor before moving the items past the
print head.
[0005] The light source outputs light (e.g., a laser beam or other
narrow light beam) across the conveyor to the movable mirror, the
movable mirror directs the light back across the conveyor to the
fixed mirror, and the fixed mirror directs the light again across
the conveyor to the light sensor. Further, the light source, the
movable mirror, and the fixed mirror are positioned relative to
each other to direct the light from the light source, reflected by
the movable mirror and the fixed the mirror, to the light sensor in
a single plane. This single plane is parallel to the plane formed
by the surface of the conveyor that is moving in the processing
direction. Further, this single plane forms a height limit above
the second plane. The height limit is a limit for items being moved
by the conveyor past the print head.
[0006] In another example, a device herein can be an inkjet printer
that includes a perforated vacuum belt having a surface that moves
in a processing direction when the belt moves. An inkjet print head
is positioned adjacent the perforated vacuum belt. Also, a light
source is positioned adjacent a first side of the perforated vacuum
belt.
[0007] Further, a movable mirror is positioned adjacent a second
side of the perforated vacuum belt. The movable mirror rotates in a
plane parallel to the surface of the perforated vacuum belt. The
first side and the second side of the perforated vacuum belt are
parallel to the processing direction, and the second side of the
perforated vacuum belt is across the perforated vacuum belt from
the first side of the perforated vacuum belt (in a second
direction, where the second direction is approximately
perpendicular to the processing direction).
[0008] Additionally, a fixed mirror is positioned adjacent the
first side of the perforated vacuum belt. More specifically, the
fixed mirror is between the light source and the inkjet print head.
A light sensor array is positioned adjacent the second side of the
perforated vacuum belt, the light sensor array is between the
movable mirror and the inkjet print head. Also, the processing
direction moves sheets of print media in a direction on the
perforated vacuum belt past the light sensor array before moving
the sheets of print media past the inkjet print head.
[0009] The light source outputs light (e.g., a laser beam or other
narrow light beam) across the perforated vacuum belt to the movable
mirror. In turn, the movable mirror directs the light back across
the perforated vacuum belt to the fixed mirror, and the fixed
mirror directs the light again across the perforated vacuum belt to
the light sensor array. Further, the light source, the movable
mirror, and the fixed mirror are positioned relative to each other
to direct the light from the light source, reflected by the movable
mirror and the fixed the mirror, to the light sensor array in a
single plane. This single plane is parallel to a plane formed by
the surface of the perforated vacuum belt. Also, this single plane
establishes a height limit above the surface of the perforated
vacuum belt (e.g., above the second plane in a third direction that
intersects the surface of the perforated vacuum belt and the second
plane). This height limit is a limit for sheets of print media
being moved by the perforated vacuum belt past the inkjet print
head.
[0010] These and other features are described in, or are apparent
from, the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Various exemplary systems and devices are described in
detail below, with reference to the attached drawing Figures, in
which:
[0012] FIG. 1 is a perspective schematic diagram illustrating
devices herein;
[0013] FIG. 2 is a top-view schematic diagram illustrating devices
herein;
[0014] FIG. 3 is a side-view schematic diagram illustrating devices
herein;
[0015] FIG. 4 is a side view schematic diagram illustrating devices
herein;
[0016] FIG. 5 is a top-view schematic diagram illustrating devices
herein;
[0017] FIG. 6 is a top-view schematic diagram illustrating devices
herein;
[0018] FIG. 7 is a top view schematic diagram illustrating devices
herein;
[0019] FIG. 8 is a side view schematic diagram illustrating devices
herein; and
[0020] FIG. 9 is a side-view schematic diagram illustrating devices
herein.
DETAILED DESCRIPTION
[0021] As mentioned above, systems that can determine the height or
thickness of the print media within a printer accurately and
inexpensively are highly valued. Many devices that determine the
height of the print media above the conveyor belt utilize light or
sonic sensors that direct light or sound energy perpendicularly
toward the surface of the conveyor belt. Such systems base the
determination of the media thickness on the reflection of the sound
or light energy from the conveyor belt and the print media
surfaces. However, such systems are inconvenient because they
require a large amount of space above the conveyor belt and
therefore consume a lot of vertical space within the printing
device unnecessarily.
[0022] Further, because such systems rely primarily upon reflection
for a height determination, their accuracy is fundamentally limited
by this methodology. In addition, such systems that rely upon
reflection for height or thickness determination may only look at
one portion of the sheet of print media at one time (e.g., along
the centerline of the print media). The systems described herein
overcome these limitations by utilizing an extremely low profile
detection system that is positioned and operates parallel to the
surface of the conveyor belt and that has increased height
accuracy.
[0023] More specifically, the devices described herein output a
light beam in a direction parallel to the surface of the conveyor
belt and reflect the light beam back and forth across the conveyor
belt and number of times using mirrors before allowing the light
beam to reach a light sensor. This allows the height (thickness) of
multiple portions of the sheet of print media to be repeatedly
checked at many different transport locations as the sheet is fed
in the process direction.
[0024] Further, the path of the light beam is maintained parallel
to the surface of the conveyor belt, which allows the height
detection capability of the system to be substantially accurate
(for a given height limit being used). Also, the components of the
device described herein are substantially outside the paper path
and are positioned generally parallel to the surface of the
conveyor belt, which is a region that usually has additional space
that is not being utilized by other components. Therefore, these
systems are not only extremely compact from a height standpoint
within the printer (where "height" is a direction perpendicular to,
and intersecting, the conveyor belt) they also utilize spaces
lateral to the conveyor belt within the printer that can generally
accommodate additional components. Therefore, the devices described
herein can be utilized within existing printing devices without
substantial modification, and these devices allow newly design
printing devices to be smaller and more compact, which makes them
easier to use, increases uses satisfaction, decreases material
usage and waste, etc.
[0025] An exemplary height sensor device 120 herein shown in FIGS.
1-8 can be used with a device having a conveyor 100 moving in a
processing direction, and a print head 104 positioned adjacent the
conveyor 100.
[0026] The height sensor device 120 includes a light source 110
positioned adjacent a first side of the conveyor 100. The first
side of the conveyor 100 is parallel to the processing direction.
This exemplary apparatus 120 also includes a movable mirror 112
positioned across the conveyor 100, adjacent a second side of the
conveyor 100. The second side of the conveyor 100 is parallel to
the processing direction, and is across the conveyor 100 from the
first side of the conveyor 100 (in a second direction that is
approximately perpendicular to the processing direction, and
parallel to the surface of the conveyor 100).
[0027] This apparatus 120 also has a fixed mirror positioned
adjacent the first side of the conveyor 100. The fixed mirror is
between the light source 110 and the print head 104. Further, a
light sensor 116 is positioned adjacent the second side of the
conveyor 100. The light sensor 116 is between the movable mirror
112 and the print head 104.
[0028] The light source 110 outputs light (e.g., a laser beam or
other narrow, focused light beam) across the conveyor 100 to the
movable mirror 112. The movable mirror 112 moves or oscillates to
direct the light back across the conveyor 100 to many points on the
fixed mirror at different points in time. The fixed mirror directs
the light again across the conveyor 100 to multiple points on the
light sensor 116 at different points in time. Further, the light
source 110, the movable mirror 112, and the fixed mirror are
positioned relative to each other to direct the light from the
light source 110, reflected by the movable mirror 112 and the fixed
the mirror, to the light sensor 116 in a single plane. This single
plane is parallel to the plane formed by the surface of the
conveyor 100 that is moving in the processing direction.
[0029] Further, this single plane forms a height limit above the
second plane. The height limit is from the conveyor 100 in a third
direction that is perpendicular to the conveyor 100 and the second
plane, and the third direction intersects the surface of the
conveyor 100 and is from the conveyor 100 toward the print head
104). The height limit is a limit for items 102 being moved by the
conveyor 100 past the print head 104. Therefore, any of the items
102 that are above this single plane will block the light beam at
certain times, preventing the light beam from reaching the light
sensor 116 at certain times. When the light sensor 116 does not
receive the beam of light which it expects to receive, this
indicates that the paper exceeds the height limit, and processing
does not allow the paper to be fed under to print heads 104, which
prevents paper jams and keeps the print heads 104 from being
damaged.
[0030] In a more specific example, which is also shown in FIGS.
1-8, a device herein can be a printer that includes a perforated
vacuum belt 100 (or any other type of conveyor) having a surface
that moves in a processing direction when the belt moves (indicated
by arrows in FIGS. 1 and 2). The perforated vacuum belt 100 is only
one example, and item 100 is also intended to illustrate standard
flat conveyors and/or rollers; however, the perforated vacuum belt
100 helps hold the sheets of print media 102 against the belt,
reducing the likelihood of contact with the print head(s) 104. The
details of vacuum belt systems are well-known to those skilled in
the art and are not shown in the drawings to avoid clutter and to
allow the salient features of the devices herein to be more clearly
seen. An inkjet print head assembly (or any other type of print
device assembly) 104 (which can contain one or many print heads) is
positioned adjacent the perforated vacuum belt 100.
[0031] The first side and the second side of the belt 100 are
parallel to the processing direction, and the second side of the
belt 100 is across the belt 100 from the first side of the belt 100
(across the belt being in a second direction, where the second
direction is approximately perpendicular to the processing
direction). Therefore, for example, the processing direction moves
sheets of print media 102 on the belt 100 past the light sensor 116
array before moving the sheets of print media past the inkjet print
head 104, and the second direction is parallel to the surface of
such sheets of print media 102, but is perpendicular to the
processing direction.
[0032] With the height sensors 120 herein, a light source 110 is
positioned adjacent the first side of the belt 100. The light
source 110 can be any light source that can produce a narrow,
focused beam of light, such as a focused incandescent light, led
lights, laser light source, etc., or any other focused light
currently known or that may be developed in the future, that may or
may not use focusing lenses, fiber-optic filters, etc.
[0033] Further, in the height sensor 120 a movable mirror 112 is
positioned adjacent the second side of the belt 100. As shown by
the curved arrow surround item 112 in FIGS. 1 and 2, the movable
mirror 112 rotates in a plane parallel to the surface of the belt
100. The movable mirror 112 can be driven by any form of motor
source, such as an oscillator, actuator, etc. (directly or
indirectly) and item 112 also generically illustrates that motor
source or actuator. The motor that moves the mirror 112 does so in
a predictable regular pattern (as controlled by the controller
discussed below) back and forth in an oscillating manner to produce
a predictable regular pattern of moving light beam striking
different locations of the fixed sensor array 116. Any disruption
to the expected light beam pattern striking the fixed sensor array
116 is interpreted by the controller (discussed below) to indicate
that there is an item that exceeds a height limit blocking the
light beam (and that the sheet of print media should not be allowed
to be processed through the print heads 104).
[0034] Additionally, in the height sensor 120 a fixed mirror (e.g.,
a mirror that does not move or rotate) is positioned adjacent the
first side of the belt 100. More specifically, the fixed mirror is
positioned along the first side of the belt 100 between the light
source 110 and the inkjet print head 104. A light sensor 116 array
(of any form, such as a CCD array, etc.) in the height sensor 120
is positioned adjacent the second side of the belt 100. The light
sensor 116 array is positioned along the second side of the belt
100 between the movable mirror 112 and the inkjet print head
104.
[0035] The light source 110 outputs light (e.g., a laser beam or
other narrow, focused light beam) across the belt 100 to the
movable mirror 112. In turn, the movable mirror 112 directs the
light back across the belt 100 to the fixed mirror, and the fixed
mirror directs the light again across the belt 100 to the light
sensor 116 array. Therefore, the light beam output by the light
source 110 crosses the belt 100 at least twice before reaching the
sensor array 116. With a light beam that crosses the process
direction multiple times, the devices herein check a greater
surface area of the print media sheet 100 and check the height of
the print media sheet 100 for a longer travel length in the
processing direction when compared to a cross-process direction
light beam that only crosses the conveyor a single time (a light
beam in the direction perpendicular to the process direction that
is not reflected back across the conveyor).
[0036] Additionally, as noted above, the rotating mirror 112
oscillates back-and-forth (in a regular pattern) in order to cause
the light beam to strike different areas of the fixed mirror 114 at
different times (as shown by the diagonal arrows in FIG. 2). More
specifically, the rotating mirror and fixed mirror 114 can be flat
mirrors. By changing the angle of the rotating mirror 112 relative
to the light source 110 and the fixed mirror 114, the location that
the light team strikes the fixed mirror 114 changes. This also
changes the location of where the light beam strikes the sensor
array 116. Therefore, as shown in FIG. 2 the height sensor 120
herein continually changes the angle at which a light beam crosses
the belt 100 and the sheet 102, from perpendicular to the process
direction (the portion of light beam being output by the light
source 110), to many different angles that are not perpendicular to
the processed direction (as shown by the diagonal arrows that
represent the light beam at different times) to allow the height
sensor 120 to repeatedly check many different portions of the print
media 102 against the height limit for a longer travel length in
the process direction, thereby increasing accuracy.
[0037] Additionally, while a non-reflected light beam in the
cross-process direction (the light beam exiting the light source
110) will cross all areas of the sheet of print media 102 a single
time as the belt 100 moves the sheet of print media 102 past such a
light source 110 in the process direction, the additional
non-perpendicular light beam angles illustrated by the diagonal
arrows in FIG. 2 allow the height of the print media to be
rechecked multiple times for a longer travel length in the process
direction by the height sensors 120 herein, thereby dramatically
increasing accuracy relative to a non-reflected cross-process light
beam (without incurring the expense of additional light sources or
sensors). The utilization of mirrors by structures herein permits
the height of the print media to be repeatedly checked at different
points in the process direction, without incurring the additional
expense associated with multiple light sources and multiple light
sensors.
[0038] Further, the light source 110, the movable mirror 112, and
the fixed mirror are positioned relative to each other to direct
the light from the light source 110, reflected by the movable
mirror 112 and the fixed the mirror, to the light sensor 116 array
in a single plane, as shown in the cross-sectional view in FIG. 3.
As also shown in FIG. 3, this single plane is parallel to a plane
formed by the surface of the belt 100.
[0039] Further, FIG. 3 illustrates that all components of the
height sensor 120 are close to the plane of the belt 100,
demonstrating that the height sensor 120 herein is compact
vertically (relative to the surface of the belt) within the
printing device. FIG. 3 also illustrates that all components of the
height sensor 120 can be positioned to not overlap the belt 100
(relative to the surface of the belt) and that such components
utilize areas lateral to the paper path for the components, which
can be areas that are more available (e.g., unused) in many printer
designs. Further, all components of the height sensor 120 can be
positioned to not contact the belt 100 or print media 102.
[0040] This single plane shown in FIG. 3 establishes a height limit
above the surface of the belt 100 e.g., above, meaning a third
direction that intersects the surface of the belt 100 and the
second plane 104 and is from the belt 100 toward the light sensor
104). This height limit is a limit for sheets of print media 102
being moved by the belt 100 past the inkjet print head 104.
[0041] For example, comparing FIGS. 3 and 4, areas of a sheet of
print media that are within the height limit (indicated in FIG. 3
by the height identifier A) allow the light beam to pass to the
sensor array 116. To the contrary, as shown in FIG. 4, if one or
more portions of the print media 102 exceed the height limit
(indicated in FIG. 4 by the height identifier B) at one or more
time periods the light beam will strike the print media 102 (be
blocked by the print media 102) and will not reach the sensor array
116. This is also shown in FIG. 5 where the light beam is shown as
being blocked by the print media 102 at different time periods. As
noted above, this disruption to the expected light beam striking
the fixed sensor array 116 are interpreted to indicate that there
is an item that exceeds a height limit blocking the light beam (and
that the sheet print media should not be allowed to be processed
through the print heads 104).
[0042] While the previous explanation discusses a single fixed
mirror 114, those ordinarily skilled in the art would understand
that multiple fixed mirrors 118, 130 could be utilized on opposite
sides of the belt 100, as shown in FIG. 6. Therefore, rather than
the light beam crossing the belt 100 three times, as is illustrated
in FIG. 2, in FIG. 6 the light beam can cross the belt 100 up to
five times, thereby allowing even more complete coverage of the
sheet of print media 102. Those ordinarily skilled in the art would
understand that additional mirrors could be included within the
structures herein, and that the drawings provided herewith only
illustrate a limited number of examples of the inventive
structure.
[0043] FIG. 7 illustrates one structure that can be utilized to
prevent sheets that exceed the height limit from reaching the print
heads. More specifically, FIG. 7 illustrates the height checking
structures discussed above in FIGS. 1-6 as item 120 and a diverter
as item 122. In operation (as controlled by the controller
discussed below) as a sheet of print media moves along the belt
100, if the height sensor 120 determines that the sheet of print
media is above the height limit, the diverter 122 can include a
movable element 124 (e.g., arm, drop shoot, air knife, etc.) that
diverts the sheet of print media off the belt 100 (potentially into
a recycle bin or other waste device). This prevents any over-height
sheets from reaching the print heads 104, preventing paper jams and
potential damage to the print heads. Alternatively, the printer can
be stopped before the sheet of media 102 reaches the print heads
104 to allow manual removal of the sheet.
[0044] Additionally, while the foregoing explanation discusses a
light beam being within a single plane to perform a height check of
a single height limit, other structures herein can utilize
multiple, parallel light beams to check multiple height limits.
More specifically, as shown in FIG. 8, the light source 110 can
output multiple light beams along multiple parallel planes
(potentially simultaneously, or sequentially) that are all parallel
to the plane formed by the surface of the belt 100. These multiple
light beams are reflected by the mirrors 112, 114 before reaching
the light sensor 116, as discussed above. The processor discussed
below can determine which of the light beams were interrupted by
the sheet of print media to classify the thickness of the sheet of
media within a specific range.
[0045] FIG. 9 illustrates a printing device 204, which can be used
with systems and devices herein and can comprise, for example, a
printer, copier, multi-function machine, multi-function device
(MFD), etc. The printing device 204 includes a controller/tangible
processor 216 and a communications port (input/output) 214
operatively connected to the tangible processor 216 and to the
computerized network 202 external to the printing device 204. Also,
the printing device 204 can include at least one accessory
functional component, such as a graphical user interface (GUI)
assembly 212. The user may receive messages, instructions, and menu
options from, and enter instructions through, the graphical user
interface or control panel 212.
[0046] The input/output device 214 is used for communications to
and from the printing device 204 and comprises a wired device or
wireless device (of any form, whether currently known or developed
in the future). The tangible processor 216 controls the various
actions of the computerized device. A non-transitory, tangible,
computer storage medium device 210 (which can be optical, magnetic,
capacitor based, etc., and is different from a transitory signal)
is readable by the tangible processor 216 and stores instructions
that the tangible processor 216 executes to allow the computerized
device to perform its various functions, such as those described
herein. Thus, as shown in FIG. 9, a body housing has one or more
functional components that operate on power supplied from an
alternating current (AC) source 220 by the power supply 218. The
power supply 218 can comprise a common power conversion unit, power
storage element (e.g., a battery, etc), etc.
[0047] The printing device 204 includes at least one marking device
(printing engine(s)) 240 operatively connected to a specialized
image processor 224 (that is different than a general purpose
computer because it is specialized for processing image data), a
media path 236 positioned to supply continuous media or sheets of
media from a sheet supply 230 to the marking device(s) 240, etc.,
and the media path includes the sheet height sensor 120 discussed
above and shown in FIGS. 1-8. After receiving various markings from
the printing engine(s) 240, the sheets of media can optionally pass
to a finisher 234 which can fold, staple, sort, etc., the various
printed sheets. Also, the printing device 204 can include at least
one accessory functional component (such as a scanner/document
handler 232 (automatic document feeder (ADF)), etc.) that also
operate on the power supplied from the external power source 220
(through the power supply 218).
[0048] The one or more printing engines 240 are intended to
illustrate any marking device that applies a marking material
(toner, inks, etc.) to continuous media or sheets of media, whether
currently known or developed in the future and can include, for
example, devices that use a photoreceptor belt or an intermediate
transfer belt, or devices that print directly to print media (e.g.,
inkjet printers, ribbon-based contact printers, etc.).
[0049] As would be understood by those ordinarily skilled in the
art, the printing device 204 shown in FIG. 9 is only one example
and the systems and devices herein are equally applicable to other
types of printing devices that may include fewer components or more
components. For example, while a limited number of printing engines
and paper paths are illustrated in FIG. 9, those ordinarily skilled
in the art would understand that many more paper paths and
additional printing engines could be included within any printing
device used with systems and devices herein.
[0050] While some exemplary structures are illustrated in the
attached drawings, those ordinarily skilled in the art would
understand that the drawings are simplified schematic illustrations
and that the claims presented below encompass many more features
that are not illustrated (or potentially many less) but that are
commonly utilized with such devices and systems. Therefore,
Applicants do not intend for the claims presented below to be
limited by the attached drawings, but instead the attached drawings
are merely provided to illustrate a few ways in which the claimed
features can be implemented.
[0051] Many computerized devices are discussed above. Computerized
devices that include chip-based central processing units (CPU's),
input/output devices (including graphic user interfaces (GUI),
memories, comparators, tangible processors, etc.) are well-known
and readily available devices produced by manufacturers such as
Dell Computers, Round Rock Tex., USA and Apple Computer Co.,
Cupertino Calif., USA. Such computerized devices commonly include
input/output devices, power supplies, tangible processors,
electronic storage memories, wiring, etc., the details of which are
omitted herefrom to allow the reader to focus on the salient
aspects of the systems and devices described herein. Similarly,
printers, copiers, scanners and other similar peripheral equipment
are available from Xerox Corporation, Norwalk, Conn., USA and the
details of such devices are not discussed herein for purposes of
brevity and reader focus.
[0052] The terms printer or printing device as used herein
encompasses any apparatus, such as a digital copier, bookmaking
machine, facsimile machine, multi-function machine, etc., which
performs a print outputting function for any purpose. The details
of printers, printing engines, etc., are well-known and are not
described in detail herein to keep this disclosure focused on the
salient features presented. The systems and devices herein can
encompass systems and devices that print in color, monochrome, or
handle color or monochrome image data. All foregoing systems and
devices are specifically applicable to electrostatographic and/or
xerographic machines and/or processes.
[0053] In addition, terms such as "right", "left", "vertical",
"horizontal", "top", "bottom", "upper", "lower", "under", "below",
"underlying", "over", "overlying", "parallel", "perpendicular",
etc., used herein are understood to be relative locations as they
are oriented and illustrated in the drawings (unless otherwise
indicated). Terms such as "touching", "on", "in direct contact",
"abutting", "directly adjacent to", etc., mean that at least one
element physically contacts another element (without other elements
separating the described elements). Further, the terms automated or
automatically mean that once a process is started (by a machine or
a user), one or more machines perform the process without further
input from any user.
[0054] It will be appreciated that the above-disclosed and other
features and functions, or alternatives thereof, may be desirably
combined into many other different systems or applications. Various
presently unforeseen or unanticipated alternatives, modifications,
variations, or improvements therein may be subsequently made by
those skilled in the art which are also intended to be encompassed
by the following claims. Unless specifically defined in a specific
claim itself, steps or components of the systems and devices herein
cannot be implied or imported from any above example as limitations
to any particular order, number, position, size, shape, angle,
color, or material.
* * * * *